Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/11/14
AREA FORECAST DISCUSSION
NWS TAUNTON MA
144 PM EST TUE DEC 9 2014
.SYNOPSIS...
A SIGNIFICANT COASTAL STORM WILL IMPACT THE REGION TODAY WITH
WINTRY PRECIPITATION AND HEAVY RAIN...ALONG WITH STRONG TO
DAMAGING WINDS. LEFTOVER LIGHT SNOW AND RAIN SHOWERS MAY PERSIST
INTO SATURDAY AS THE DISTURBANCE ALOFT STALLS ACROSS NEW ENGLAND.
IMPROVING CONDITIONS EXPECTED SUNDAY AND ESPECIALLY EARLY NEXT
WEEK AS HIGH PRES BUILDS IN FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
1040 AM UPDATE...
TEMPS HAVE BEEN SLOWLY BUT STEADILY RISING ACROSS E MA/RI/NE CT
THROUGH 15Z...BUT HOLDING RIGHT AROUND FREEZING FROM THE INTERIOR
MERRIMACK VALLEY THROUGH CENTRAL AND NW MA. NOTING THAT TEMPS HAVE
BEEN WARMING ALOFT WITH RATHER STRONG LOW LEVEL INVERSION AS SEEN
ON 12Z KOKX SOUNDING /UP TO +5C AT 866 MB AND FREEZING LEVEL UP TO
6500 FT/...SO TENDING TO MIX DOWN WITH THE AREA OF HEAVY RAINFALL
MOVING INTO S COASTAL AREAS. THIS WILL HELP TEMPS RISE EVEN ACROSS
INLAND AREAS AS THE SLUG OVER HEAVY PRECIP MOVES IN.
NOTING 1005 HPA LOW PRES JUST NE OF THE DELMARVA PENINSULA AT
15Z...WHICH APPEARS PRETTY MUCH ON TRACK THOUGH TUCKED A BIT
CLOSER TO THE COAST.
NOTING REPORTS OF 0.75 TO 1 INCH/HR RAINFALL RATES ACROSS S CT AND
LONG ISLAND OVER THE LAST HOUR OR TWO. THIS...ALONG WITH GUIDANCE
FROM NESDIS SATELLITE PRECIP ESTIMATE REPORTING A MAX PWAT PLUME
OF 1.65 INCHES WELL S OF LONG ISLAND EARLIER THIS MORNING. VERY
COLD CLOUD TOPS ALSO NOTED S OF LONG ISLAND. DRY SLOT NOTED ON NE
REGIONAL 88D RADAR E OF KACY...WHICH WILL SLOWLY SHIFT N-NE DURING
THE DAY. ALSO NOTED 06Z GFS OP RUN SUGGESTING UP TO 1.5 TO 2 INCH
RAINFALL RATES IN TWO 6-HOUR PERIODS BETWEEN NOW AND 00Z MOVING
ACROSS RI/E MA. CONSIDERING THE NESDIS OBSERVATIONS...FELT THIS
WAS NOT TOO BAD SO UPDATED TO INCREASE PRECIP AMOUNTS. THIS GIVES
STORM TOTAL PRECIP OF 2.5 TO 3.5 INCHES...WHICH MAY LEAD TO
LOCALIZED URBAN AND POOR DRAINAGE FLOODING ACROSS RI/E MA.
HAVE UPDATED FORECAST TO INCLUDE HEAVY RAINFALL MENTION TO THE
FORECAST. WILL ALSO MONITOR FOR THE CHANCE OF ANY THUNDER THAT MAY
NEED TO BE ADDED ACROSS S COASTAL RI/MA. NOTING C/G LIGHTNING TO
THE E OF THE DRY SLOT. ALSO UPDATED TEMPS/DEWPTS TO BRING
CONDITIONS CURRENT. REMAINDER OF FORECAST IN PRETTY GOOD SHAPE.
PREVIOUS DISCUSSION...
* SYNOPTICALLY...
PRESENT OFFSHORE LOW OFF THE MID-ATLANTIC CONUS BECOMES USURPED BY
AN AMPLIFYING TROUGH DIGGING THROUGH THE E-CONUS. ACROSS A REGION OF
FAVORABLE BAROCLINICITY / ATTENDANT DYNAMICS / STRONG FORCING AND
DEEP-LAYER ASCENT YIELDS A RAPIDLY DEEPENING AREA OF LOW PRESSURE
OFF THE DELMARVA PENINSULA THIS MORNING LIFTING N INTO S NEW ENGLAND
BY EVENING. THE LOW BECOMES STALLED AND CUTOFF FROM THE MEAN FLOW UP
AGAINST HIGH PRESSURE ON NEARLY ALL SIDES AS WE GO INTO THE WEEK.
* HEAVY RAIN AND FLOODING...
AS THE LOW DEEPENS...EXPECT DECENT LOW-LEVEL TROWALING OF THE
WARM-CONVEYER-BELT BENEATH THE RRQ/LFQ OF ATTENDANT UPPER-LEVEL
JET AXES. COMBINATION OF THE CONVERGENT LEADING NOSE OF ISENTROPIC
UPSLOPE LENDING TO THE TIGHTENING OF THE THERMAL GRADIENT AGAINST
NEIGHBORING HIGH PRESSURE YIELDING STRONG FRONTOGENETICAL FORCING
IN A REGION OF MINOR -EPV INSTABILITY BENEATH AFOREMENTIONED DEEP
LAYER ASCENT LIKELY TO RESULT IN A ROUGHLY W-E BANDING SETUP OF
HIGHER WSR-88D RETURNS WITHIN A WIDESPREAD COMMA-SHAPED PRECIP
FIELD ALONG THE N-PERIPHERY OF THE H85 LOW WITH THE FRONT-END
THUMP OF PRECIP ANTICIPATED AROUND MIDDAY AND PERSISTING INTO
EARLY EVENING.
WILL EXPAND THE FLOOD WATCH TO INCLUDE CAPE COD AND NANTUCKET.
WITH HEIGHT OF THE E-NE WINDS AND HEAVY RAIN CONCURRENT WITH
TIMING OF HIGH TIDE CENTERED AROUND 1 PM BELIEVE SURGE ALONG WITH
BUILDING WAVE HEIGHTS /SEE THE MARINE DISCUSSION BELOW FOR MORE
DETAILS/ WILL RESULT IN POOR-DRAINAGE ISSUES FOR COASTAL
COMMUNITIES. ANTICIPATE DRAINS TO BACK-UP BECOMING OVER-TOPPED
RESULTING IN SUSCEPTIBLE LOW- LYING AND POOR-DRAINAGE AREAS TO
BECOME FLOODED.
AM ALSO CONCERNED FOR EVEN THOSE COMMUNITIES WITHIN THE COASTAL
PLAIN IN VICINITY OF RIVERS THAT ARE INFLUENCED BY THE TIDE /I.E.
TAUNTON RIVER...LOWER CONNECTICUT/. COULD ALSO SEE SOME EXACERBATED
FLOOD ISSUES FOR THESE AREAS.
OTHERWISE REMAINDER OF THE FLOOD WATCH REMAINS IN PLACE. PWATS OF
1.25-INCHES FORECAST /ROUGHLY +2 STANDARD DEVIATIONS ABOVE-NORMAL/
AND FORECAST RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS ANTICIPATED. GROUND IS PRETTY SOLID /IMPERVIOUS/ THUS EXPECT
MOST OF THE RAINFALL TO BECOME RUNOFF. MAJORITY OF MAINSTEM RIVERS
OVER THE INTERIOR SHOULD BE ABLE TO HANDLE THE RAIN...SO CONCERNS
LIE IN THE REALM OF URBAN / POOR DRAINAGE FLOODING...ESPECIALLY IF
DRAINS ARE STILL LEAF-CLOGGED. BIGGEST AREA OF CONCERN IS WITHIN THE
METRO-AREA CORRIDORS...ESPECIALLY BOSTON-PROVIDENCE. MAY NEED TO
EXPAND THE WATCH ACROSS N-CENTRAL AND NW MA PENDING THE TIMING AT
WHICH WINTRY-PRECIP TYPES TRANSITION TO RAIN.
* WINTRY PRECIPITATION...
OUTCOMES DEPENDENT ON THERMAL FIELDS ALOFT...WHERE AROUND H925-H85
BY MORNING CONDITIONS ARE WARMING CONSIDERABLY UP AGAINST COLDER AIR
AND HIGH PRESSURE SITUATED N/W. A SW-NE FREEZING LINE AROUND NW-CT
INTO S NH INITIALLY MODIFIES NW AS THE LOW DEEPENS RESULTING IN THE
INCREASE OF THE SE WARM-MOIST-CONVEYER-BELT. EXPECT THICKNESSES
TO GRADUALLY RISE DURING THE HEIGHT OF THE EVENT INTO EVENING.
AT THE SURFACE...AREAS BELOW FREEZING ERODE WITH INCREASING ONSHORE
E/NE-WINDS DURING THE MORNING /MORE ON THAT LATER/. UNCERTAINTY
CONTINUES WITH 09.0Z HIGH-RES MODELS DIFFERING IN TIMING OF EROSION.
AS MENTIONED IN PRIOR DISCUSSIONS...FOR AREAS THAT ARE WITHIN OR
ON THE CUSP OF BELOW-FREEZING TEMPERATURES BY 1-2C...LINGERING AN
HOUR OR TWO MORE OR LESS CAN MAKE ALL THE DIFFERENCE WITH REGARDS
TO WINTER-WEATHER HEAD-LINES. H975-925 AGEOSTROPHIC FLOW IS
NOTABLY PERSISTENT AND STRONG OUT OF THE W AS THE LOW INTENSIFIES
TOWARDS S NEW ENGLAND. BUT NOT MUCH OF A N-COMPONENT NOR FROM
ARCTIC-SOURCE REGIONS...SO BELIEVE THIS WILL DO LITTLE TO MAINTAIN
/ PERSIST COLD AIR OVER THE REGION AGAINST STRONG ONSHORE E-FLOW.
WILL GO CLOSE TO THE NEAR-TERM HIGH-RES GUIDANCE WHILE INCORPORATING
THE WRF-NMM WITH REGARDS TO THERMAL FIELDS...WHICH ARE HANDLING THE
SURFACE TEMPERATURES DECENTLY. PREFERENCE TO THE 09.0Z ECMWF IS ALSO
GIVEN ESPECIALLY WHEN EVALUATING H100-H85 THICKNESSES. ONLY WRF-ARW
AND RAP LEAN ON THE WARM SIDE OF THE GUIDANCE OVER ALL OTHERS.
ALSO WILL GO WITH A TOP-DOWN APPROACH TOWARDS PRECIPITATION-TYPE
THAT INCORPORATES THE INCREASING MOISTURE FROM THE S WITHIN OR
ABOVE THE DENDRITIC GROWTH ZONE REGION.
SO OVERALL...EXPECTING THE GRADUAL EROSION OF THE COASTAL-FRONT WITH
INCREASING ONSHORE E-FLOW. PUSH OF WARMER AIR ALOFT AHEAD OF THE
DEEPENING LOW WILL RESULT IN PRECIP-TYPE TRANSITION FAIRLY QUICKLY
TO A SLEET / FREEZING RAIN MIX. THIS HAS SUBSEQUENTLY BUMPED DOWN
SNOWFALL AMOUNTS RESULTING IN A RANGE OF 2-4 INCHES ACROSS NW MA.
MOST OF THE REGION CHANGES OVER TO RAIN BY LATE MORNING INTO MIDDAY
WITH ONLY THE HIGHER ELEVATIONS OF THE BERKSHIRES CONTINUALLY UNDER
THE THREAT OF FREEZING RAIN.
HAVE DROPPED WINTER-STORM WATCHES AND REPLACED WITH WINTER WEATHER
ADVISORIES. HAVE TRIMMED THE EASTERN-EXTENT WITH EROSION OF THE
COASTAL FRONT AND THE SURGE OF WARMER AIR ONSHORE. AGAIN...THE
THERMAL FIELDS DISCUSSION ABOVE GIVE AN INDICATION OF PREFERRED
MODEL GUIDANCE. SHOULD SEE WINTER WEATHER HEADLINES DROP MAINLY
AROUND THE MIDDAY HOURS.
MID-LEVEL DRY-SLOT WRAPPING INTO A DEVELOPING OCCLUSION BEGINNING
TUESDAY EVENING SHOULD RESULT IN A LULL OF PRECIPITATION AS WE GO
INTO WEDNESDAY MORNING.
* STRONG TO DAMAGING WINDS...
NOTING E-WINDS 1-2 KFT AGL WILL BE AROUND 55 MPH AROUND THE MIDDAY
INTO AFTERNOON HOURS...THE PRESENCE OF WARMER AIR ALOFT LENDING TO
AN INVERSION JUST ABOVE THE SURFACE MAKES IT DIFFICULT TO CONSIDER A
HIGH WIND WARNING. THIS DESPITE WARMER AIR WIGGLING ITS WAY UP FROM
THE S AT THE SURFACE...AND A WARMER OCEAN /THOUGH NOW AROUND THE LOW-
50S/. BOUNDARY-LAYER MIXING WILL BE LIMITED. HIGH-END WIND ADVISORY
CRITERIA IS EXPECTED...BUT DO NOT EXPECT WIDESPREAD GUSTS EXCEEDING
HIGH WIND WARNING CRITERIA. THUS WENT WITH THE WIND ADVISORY.
COULD PRECIPITATION-DRAG PROCESSES BRING FASTER MOMENTUM TO THE
SURFACE? YES...IT IS QUITE POSSIBLE...EVEN IF THUNDERSTORMS ARE IN
THE MIX WHICH IS IN THE FORECAST FOR THE FAR SE-WATERS ADJACENT TO
THE CAPE AND ISLANDS. HAVE GONE WITH THE HEADLINES THAT CONVEY THE
HIGHEST CONFIDENCE.
* COASTAL FLOODING...
SEE TIDES/COASTAL FLOODING SECTION BELOW FOR DETAILS.
&&
.SHORT TERM /WEDNESDAY/...
SEE LONG TERM SECTION BELOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* REMAINING UNSETTLED WITH SCT RAIN/SNOW SHOWERS THROUGH THE END OF
THE WEEK AND POSSIBLY INTO SAT
* IMPROVING CONDITIONS SUNDAY AND ESPECIALLY EARLY NEXT WEEK
CLOSED LOW WILL MEANDER ACROSS NEW ENG THROUGH THE END OF THE WEEK
AND LIKELY INTO THE WEEKEND AS NORTH ATLANTIC BLOCKING IS VERY SLOW
TO BREAK DOWN. TYPICALLY THESE BLOCKS ARE SLOWER TO BREAK DOWN THAN
GUIDANCE SUGGESTS SO THREAT OF SCT RAIN/SNOW SHOWERS WILL LIKELY
PERSIST INTO SATURDAY. CERTAINLY NOT LOOKING AT WIDESPREAD PRECIP
AND MOST OF THE TIME WILL BE DRY...BUT THERE WILL BE SCT RAIN/SNOW
SHOWERS AT TIMES AS COLD POOL ALOFT WITH 500 MB TEMPS -25 TO -30C
AND DEEPER MOISTURE AXIS WILL BE PRESENT INTO SATURDAY. LOW
PREDICTABILITY ON TIMING OF ANY SHOWERS...BUT DURING WED NIGHT SNE
WILL BE ON SE EDGE OF COMMA HEAD AND QG FORCING OVER NNY AND THERE
IS POTENTIAL FOR SOME MINOR SNOW ACCUM ACROSS WESTERN MA.
IMPROVING CONDITIONS EXPECTED BY SUNDAY AND ESPECIALLY EARLY NEXT
WEEK AS THE CLOSED LOW AND COLD POOL ARE FINALLY FORECAST TO MOVE
AWAY FROM THE NEW ENG WITH SFC AND UPPER LEVEL RIDGING BUILDING IN
AND GOOD DRYING IN THE LOW AND MID LEVELS. BY NEXT TUESDAY...NEXT
NORTHERN STREAM SHORTWAVE WILL BE APPROACHING AND WE COULD HAVE A
FRONTAL PASSAGE WITH A LOW PROB OF SHOWERS.
WE USED A BLEND OF AVAILABLE GUIDANCE. LOOKING AT SLIGHTLY BELOW
TEMPS THROUGH THE WEEKEND...MODERATING A BIT EARLY NEXT WEEK.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY MORNING/...
12Z UPDATE...
TODAY INTO TONIGHT...MODERATE CONFIDENCE.
MIX OF MVFR-IFR CIGS / VSBYS WITH MAINLY +RA. AN ISOLATED TSRA IS
POSSIBLE FOR FAR SE-COASTAL TERMINALS. OTHERWISE GRADUAL EROSION
TO N/W OF FZRA/PL/SN INTO THE EARLY-AFTERNOON HOURS DURING WHICH
TIME WINDS WILL INCREASE OUT OF THE E WITH STRONGEST GUSTS ALONG
THE E-SHORELINE MAINLY AROUND 40 KT WITH LOCALLY HIGHER GUSTS UP
TO 50 KT. WILL ALSO SEE AN ACCOMPANYING LLWS THREAT WITH WINDS
AROUND 2 KFT AGL OUT OF THE E AROUND 60 KTS.
KBOS TERMINAL...MODERATE CONFIDENCE.
FEEL CONFIDENT WITH TRENDS BUT NOT SO MUCH WITH SPECIFICS. HIGH
CONFIDENCE OF CONTINUED +RA WITH INCREASING E-WINDS. GUSTS UP TO
40 KT ANTICIPATED TOWARDS THE MIDDAY HRS. WIND ADVISORY LENDING
TO ISSUANCE OF AIRPORT WEATHER WARNING.
KBDL TERMINAL...MODERATE CONFIDENCE.
FZRA PERSISTING INTO THE EARLY-MORNING HOURS...THEN CHANGING OVER
TO RAIN. NOT ABSOLUTELY CERTAIN ON TIMING BUT CONFIDENT WITH
TRENDS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
WEDNESDAY NIGHT AND THURSDAY...MODERATE CONFIDENCE. AREAS OF
MVFR/IFR IN SCATTERED RAIN/SNOW SHOWERS.
FRIDAY AND SATURDAY...MODERATE CONFIDENCE. MIX OF VFR CIGS AND
MVFR. ISOLATED RAIN/SNOW SHOWERS.
SUNDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TONIGHT/...HIGH CONFIDENCE.
1030 AM UPDATE...
THROUGH THIS AFTERNOON NOTING SEAS HAVE INCREASED TO 10-15 FT ON
THE OUTER WATERS AND EVEN PUSHING INTO MASS BAY ON THE E FETCH.
HAVE UPDATED TO INCREASE THE SEAS TO AT LEAST THESE LEVELS. EXPECT
STRONGEST WINDS TO PUSH INTO THE WATERS. GUSTS UP TO 33 KT REPORTS
AT BUOY 44020 /NANTUCKET SOUND/ AND 31 KT AT BOTH MASS BAY BUOYS
WITH 35 KT GUSTS AT THE BUZZARDS BAY TOWER AT 15Z. FORECAST
THROUGH TODAY PRETTY MUCH ON TRACK.
PREVIOUS DISCUSSION...
HAVE GONE WITH STORM WARNINGS FOR THE OUTER WATERS WITH THE
EXPECTATION OF GUSTS AROUND 45-50 KT. BUT GREATER CONFIDENCE OF
THE INNER WATERS REACHING HIGH-END GALE WARNING CRITERIA
PERMITTED THE DISCONTINUING OF THE STORM WATCH. CAN NOT RULE OUT
AN ISOLATED GUST UP TO 50 KTS OVER THE INNER WATERS...BUT WITH IT
NOT ANTICIPATED TO BE WIDESPREAD...KEPT WITH GALE WARNINGS.
STRONGEST E-WINDS OCCURRING TOWARDS THE MIDDAY AND CONTINUING INTO
THE EARLY EVENING HOURS.
SEAS BUILDING 15 TO 20 FEET WITH INCREASING E WINDS AHEAD OF A
DEEPENING AREA OF LOW PRESSURE OF THE DELMARVA PENINSULA PRESENTLY
AS IT LIFTS N INTO S NEW ENGLAND TOWARDS THIS EVENING. EXPECT
ACCOMPANYING HEAVY RAIN WHICH WILL YIELD VISIBILITY RESTRICTIONS
ON THE WATERS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...MODERATE CONFIDENCE.
WEDNESDAY NIGHT AND THURSDAY...EXPECT MOSTLY SW WINDS WITH GUSTS TO
25 KT...ESPECIALLY S WATERS AS LOW PRES MOVES SLOWLY N THROUGH NEW
ENG. ROUGH SEAS CONTINUE...UP TO 10-11 FT SOUTHERN WATERS.
FRIDAY INTO SATURDAY...GRADIENT RELAXES AND EXPECT DIMINISHING WIND
AND SEAS. WEST WINDS FRI GRADUALLY VEERING TO NORTH BY SAT. SEAS
SUBSIDING BELOW SCA BY SAT.
SATURDAY NIGHT AND SUNDAY...NORTHERLY WINDS EXPECTED TO INCREASE A
BIT AS GRADIENT INCREASES. CHANCE FOR GUSTS TO 25 KT...ESPECIALLY E
WATERS.
&&
.HYDROLOGY...
UPDATED 950 AM TUE...
EXPANDED FLOOD WATCH TO INCLUDE MARTHAS VINEYARD AND BLOCK ISLAND.
ALTHOUGH RAINFALL TOTALS WILL BE 1.5 TO 2.5 INCHES...COMBINATION
OF RAINFALL AND RISING TIDE THROUGH EARLY AFTERNOON MAY LEAD TO
SIGNIFICANT FLOODING ESPECIALLY ON E/SE SHORELINES. BUOYS
REPORTING 5-6 FT SEAS ON NANTUCKET SOUND AND 11 FT SE OF BLOCK
ISLAND. SIMILAR SITUATION FOR CAPE COD AND NANTUCKET.
MAIN CONCERN CONTINUES TO BE POTENTIAL FOR SIGNIFICANT URBAN
FLOODING...ESPECIALLY IN RI AND E MA. ALREADY SEEING RAINFALL
RATES OF NEARLY 2 INCHES PER HOUR ACROSS SOUTHERN CT /KSNC ASOS/
WHICH WILL TRANSLATE OVER OUR AREA BY EARLY AFTERNOON. SOME OF THE
URBAN HOT SPOTS SUCH AS PEABODY...FALL RIVER...NEW BEDFORD AND
CRANSTON MAY BE ESPECIALLY VULNERABLE TO FLOODING. TOTALS OF 2 TO
3 INCHES ARE EXPECTED WITH A FEW 3 OR 4 INCH TOTALS NOT OUT OF
QUESTION NEAR I-95 CORRIDOR.
FLOODING OF SMALL STREAMS IS ALSO A POSSIBILITY...BUT WORST CASE
WOULD BE FOR MINOR FLOODING IF TOTALS EXCEED 3 INCHES.
NOT EXPECTING FLOODING OF LARGER RIVERS. LATEST NERFC GUIDANCE
BRINGS LOWER CT RIVER AT MIDDLE HADDAM TO ACTION STAGE...WHICH IS
PRIMARILY BASED ON SURGE OF 2 FT INTO LOWER CT RIVER. WE MAY ALSO
SEE SIMILAR SURGE ALONG PAWCATUCK RIVER NEAR WESTERLY RI WHICH
COULD BRING RISES SLIGHTLY HIGHER THAN CURRENTLY FORECAST.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY CONTINUES FOR EASTERN MA. COMBINATION OF
WINDS / SEAS / SURGE OF AROUND 1.5 TO 2 FEET DURING THE MIDDAY
HIGH-TIDE YIELDS THE LIKELIHOOD OF OBSERVING MINOR COASTAL
FLOODING AND BEACH EROSION FOR E-FACING SHORELINES WHERE SEAS OF
12 TO 15 FEET ARE POSSIBLE.
AS NOTED IN THE HYDROLOGY PORTION ABOVE...LOCAL STREAMS AND
TRIBUTARIES EMPTYING INTO THE SEA COULD SEE BACK-FILLING ISSUES AS
THE HEAVY RAIN IS ANTICIPATED DURING THE TIME OF HIGH-TIDE. COULD
SEE FLOODING ISSUES EXACERBATED FOR EASTERN MA SHORELINE
COMMUNITIES.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR CTZ002>004.
MA...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR MAZ005>007-011>024.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR MAZ007-014>016-
019>024.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ007-015-016-019-022-024.
RI...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR RIZ001>008.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR RIZ006>008.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ230>234-251.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ235>237.
STORM WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ250-254>256.
&&
$$
SYNOPSIS...KJC
NEAR TERM...EVT
SHORT TERM...SIPPRELL
LONG TERM...KJC
AVIATION...KJC/EVT
MARINE...KJC/EVT
HYDROLOGY...STAFF
TIDES/COASTAL FLOODING...STAFF
AREA FORECAST DISCUSSION
NWS ALBANY NY
1240 PM EST TUE DEC 9 2014
.SYNOPSIS...
A SLOW MOVING COASTAL STORM WILL BRING A VARIETY OF
WINTER WEATHER TO THE REGION FOR TODAY INTO TONIGHT. WHILE MANY
VALLEY AND EASTERN AREAS WILL SEE A TRANSITION OF A WINTRY MIX TO
RAIN...THE PRECIPITATION WILL BE MAINLY SNOW ACROSS THE CATSKILLS
AND ADIRONDACKS...WITH A MODERATE TO HEAVY ACCUMULATION POSSIBLE IN
THESE HIGH TERRAIN AREAS. WITH THE STORM REMAINING CLOSE TO THE
REGION...SOME ADDITIONAL RAIN AND SNOW WILL OCCUR WEDNESDAY INTO
THURSDAY AS WELL...WITH SOME ADDITIONAL SNOW ACCUMULATION POSSIBLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1014 AM EST...A 1004 HPA COASTAL LOW CONTINUES TO BE JUST
E/SE OF THE DELMARVA REGION THIS MORNING ACCORDING TO THE LATEST
MSAS MSLP ANALYSIS. THE BEST 3-HR MSLP /5-6 HPAS/FALLS ARE NORTH
OF THE SFC CYCLONE. THE LATEST KENX VWP SHOWS A STRONG E/SE LLJ
IN THR 3-6 KFT AGL LAYER OF 25-35 KTS. THIS PRONOUNCED LLJ HAS
YIELDED SOME SIGNIFICANT DOWNSLOPING OFF THE SRN GREENS...NRN
BERKS...AND THE NRN TACONICS. THE PCPN IS FINALLY TRYING TO EXPAND
NORTHWARD INTO THE UPPER HUDSON REGION...AND SRN VT. THE SRN DACKS
ARE ALSO SLOWLY...BUT FINALLY...GETTING INTO A THE PCPN SHIELD. THE
LLJ CONTINUES TO INTENSIFY JUST S/SE OF THE REGION...AND THE BEST
QG LIFT WITH THE EARLY PHASES OF THE STORM IS OVER COASTAL SRN NEW
ENGLAND AND LONG ISLAND AT THIS TIME. THE STRONG LIFT WILL IMPACT
THE REGION IN THE AFTERNOON.
PTYPES HAVE FAVORED SLEET AND FREEZING RAIN THIS MORNING. THE 12Z
KALY SOUNDING INDICATES A SLEET PROFILE. SOME HAS OCCURRED IN THE
CAPITAL DISTRICT WITH THE FREEZING RAIN/DRIZZLE. SOME ICE REPORTS
HAVE COME IN...WITH PERU IN THE S-CNTRL BERKS HAVING TWO TENTHS OF
AN INCH. THE COLUMN CONTINUES TO WARM WITH KPOU ABOVE FREEZING
WITH LIGHT RAIN...WHICH SHOULD TRANSITION TO MDT-HVY RAIN OVER THE
NEXT HOUR OR TWO. WE WILL LET THE ADVISORY RUN UNTIL 11 AM...FOR
ERN ULSTER/DUTCHESS/LITCHFIELD COUNTIES...AS SOME TEMPS ARE
SLIGHTLY BELOW OR ARE HOVERING NEAR THE FREEZING MARK.
FURTHER NORTH...THE DOWNSLOPING HAS ALLOWED KPSF/KAQW/KDDH TO
ALLOW JUMP ABOVE FREEZING INTO THE MID AND U30S. SOME WET BULB
COOLING SHOULD LOWER THESE TEMPS CLOSER TO FREEZING. PTYPES WERE
ATTEMPTED TO BE ADJUSTED ACCORDING THE HOURLIES AND A GFS/ECMWF
BLEND. MIXED PCPN WILL LIKELY LINGER FOR THE CAPITAL
REGION...N-CNTRL TACONICS...BERKSHIRES...AND SRN VT INTO THE AFTERNOON BEFORE
CHANGING TO RAIN. FURTHER NORTH AND WEST WILL HAVE THE BEST CHC OF
SNOW...WITH A LIGHT MIXED TO SLEET/FREEZING RAIN/RAIN...BEFORE
GOING BACK TO SNOW OVERNIGHT...BUT THIS WILL CONTINUE TO BE FINED
TUNED.
SOME OF THE PREVIOUS DISCUSSION FOLLOWS FOR THIS AFTERNOON AND
TONIGHT...
THERE WILL BE A SHARP CUTOFF BETWEEN SNOW VS. WINTRY MIX VS. RAIN.
THE 3KM HRRR SHOWS THAT SNOW SHOULD ACCUMULATE ACROSS THE
CATSKILLS/HELDERBERGS AND POINTS WESTWARD INTO THIS AFTERNOON.
FURTHER NORTH...THE PRECIP WILL EXPAND INTO THE WRN MOHAWK VALLEY
AND ADIRONDACKS BY THE EARLY AFTN HOURS. PRECIP LOOKS TO BE MAINLY
SNOW FOR THE MOHAWK VALLEY/ADIRONDACKS...BUT WILL LIKELY MIX FOR
THE SARATOGA/GLENS FALLS AREA. EVEN UP THERE...A CHANGEOVER TO
RAIN LOOKS TO OCCUR DURING THE AFTN HOURS...AS WARM AIR...BOTH AT
THE SFC AND ALOFT...WILL BE MOVING INTO THE AREA.
FURTHER EAST...THE PRECIP WILL CHANGE TO A WINTRY MIX FOR SOUTHERN
VT/BERKSHIRES AS WELL...EVEN ACROSS THE HIGH TERRAIN...AS WARM
AIR ALOFT OF NEARLY 3 DEGREES C MOVES OVER THE AREA FROM THE EAST.
SOME SNOW/SLEET WILL LIKELY ACCUMULATE BEFORE THE CHANGEOVER...BUT
THE CHANGEOVER WILL PREVENT WARNING LEVEL SNOW FROM OCCURRING. SOME
STRONG WINDS ARE POSSIBLE ACROSS THE SRN GREENS...TACONICS AND
BERKSHIRES...WITH SOME GUSTS OF 25-40 MPH POSSIBLE. THE FULL
BRUNT OF THE LOW LEVEL JET DOESN/T LOOK LIKE IT WILL BE ABLE TO
MIX DOWN DUE TO STABLE LOW LEVELS...BUT SOME GUSTS ARE STILL
POSSIBLE...ESP IN AREAS THAT CHANNEL E-SE FLOW WELL. WE WILL
CONTINUE TO MENTION THIS WIND THREAT IN OUR HWO STATEMENT.
AS THE BEST ISENTROPIC LIFT SHIFTS NORTH AND EAST OF THE REGION
THIS EVENING...STEADY PRECIP WILL START TO SHUT OFF ACROSS OUR
AREA. THE SFC LOW WILL BE MEANDERING OVER THE NYC/LONG ISLAND
AREA...AND THE 500 HPA LOW WILL BECOME CUTOFF OVER THE DELMARVA
AREA. AS A RESULT...SOME ADDITIONAL ON AND OFF PRECIP WILL OCCUR
OVERNIGHT DUE TO THE PVA/CYCLONIC FLOW...BUT IT WILL NOT BE
STEADY OR HEAVY. THERE WILL STILL BE SOME ABOVE FREEZING TEMPS
ALOFT...AND THERE MAY EVEN BE A LACK OF ICE NUCLEI IN THE
CLOUDS...AS THE BEST DEEPER AND COLDER CLOUD TOPS SHIFT AWAY FROM
THE AREA. BECAUSE OF THIS...SOME FREEZING RAIN/DRIZZLE MAY
OCCUR...ALONG WITH SOME BURSTS OF SNOW/RAIN/SLEET AS WELL. TEMPS
LOOK TO HOLD STEADY IN THE LOW TO MIDDLE 30S ACROSS THE ENTIRE
REGION.
BECAUSE OF ALL OF THIS...WINTER STORM WARNINGS WERE NOT ISSUED
OUTSIDE THE CATSKILLS/MOHAWK AND SCHOHARIE VALLEY/ADIRONDACKS
BECAUSE WARNING LEVEL SNOWFALL /7 INCHES IN 12 HOURS OR 9 INCHES
IN 24 HOURS/ IS NOT EXPECTED. STILL...A WINTRY MIX...EVEN THOUGH
IT WILL GO OVER TO RAIN...WILL MAKE FOR HAZARDOUS TRAVEL IN THE
CAPITAL REGION/GLENS FALLS AND SARATOGA AREAS/BERKSHIRES/SOUTHERN
VT/...AND THIS IS WHY THE WINTER WEATHER ADVISORY HAS BEEN ISSUED
FOR THESE LOCATIONS. SNOW ACCUMULATION IN THESE AREAS WILL VARY
BASED ON ELEVATION...WITH JUST UP TO A FEW INCHES IN THE VALLEY
AREAS...AND 2 TO 6 INCHES ACROSS THE HIGH TERRAIN. JUST A COATING
TO AN INCH OF SNOW/SLEET/ICE IS EXPECTED FOR THE
POUGHKEEPSIE/KINGSTON AREA AND NW CT...AS PRECIP SHOULD QUICKLY GO
OVER TO RAIN THERE THIS MORNING. HOWEVER...THE FLOOD WATCH REMAINS
IN EFFECT...AS HEAVY RAINFALL MAY LEAD TO SOME FLOOD CONCERNS. SEE
OUR HYDRO DISCUSSION FOR MORE DETAILS ON THIS THREAT.
MEANWHILE... 6 TO 12 INCHES LOOK TO ACCUMULATE IN THE
CATSKILLS...HELDERBERGS...MOHAWK AND SCHOHARIE VALLEYS...AND
ADIRONDACKS. EVEN IN THESE AREAS...SOME SLEET/FREEZING RAIN IS
POSSIBLE AT TIMES...AND VALLEYS WILL BE ON THE LOWER END OF THE
RANGE...WITH THE HIGHEST AMOUNTS IN THE HIGH PEAKS OF THE
CATSKILLS IN THE GREENE COUNTY...AND IN THE HIGHEST PEAKS OF THE
SRN ADIRONDACKS OF WARREN COUNTY. THE SNOW WILL BE RATHER
WET...AND THIS MAY MAKE FOR SOME POWER OUTAGES/DOWNED TREE
LIMBS...ESP CONSIDERING THAT STRONG NORTH WINDS ARE EXPECTED.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
A NEARLY VERTICALLY STACKED LOW OVER NEW ENGLAND WILL KEEP OUR
WEATHER UNSETTLED THROUGH THE SHORT TERM PERIOD.
WHILE DIFFICULT TO ASCERTAIN WHAT WAVE/S/ WILL TRIGGER ADDITIONAL
PRECIPITATION...MOISTURE WILL WRAP IN OFF THE ATLANTIC TO KEEP THE
HIGH PROBABILITIES IN THE FORECAST. THE BEST LOCATIONS WILL BE
ALONG THE I90 CORRIDOR AND POINTS NORTHWARD. AS FOR THERMAL
PROFILES...WE WILL BE COOLING DOWN THE COLUMN WHERE MOST OF THIS
PRECIPITATION WILL BE IN THE FORM OF SNOW. THERE WILL BE SOME
RAIN/SNOW MIXTURE INTO THE VALLEY LOCATIONS DURING THE LATE MORNING
INTO THE MID AFTERNOON HOURS. THE BEST CHANCE FOR ADDITIONAL
ACCUMULATIONS WILL BE INTO THE HIGHER TERRAIN. AS FOR THE
SPECIFIC...
WEDNESDAY...LATEST TRENDS IN THE MODEL GUIDANCE POINT TOWARD A MORE
SIGNIFICANT SURGE OF MOISTURE OFF THE ATLANTIC AS THE MAIN UPPER LOW
REMAINS JUST OFF THE JERSEY SHORE. MOISTURE ADVECTION AND HIGHER
THETA-E /TROWAL/ BACK INTO PORTIONS OF EASTERN NEW YORK AND WESTERN
NEW ENGLAND. SPECIFIC HUMIDITIES REMAIN RATHER HIGH OF 3-4 G/KG SO
WHERE IT DOES SNOW...WE COULD SEE ADDITIONAL ACCUMULATIONS OF SNOW.
PER THE LATEST NCEP MODEL SUITE AND 00Z ECMWF...THIS SEEMS TO LINE
UP FOR OUR NORTHERN HALF OF THE CWFA. ADDITIONAL FINE TUNING WILL
TAKE PLACE AS PER CSTAR RESEARCH...THESE UPPER LOWS ARE QUITE
PROBLEMATIC WITH PROVIDING SPECIFICS WHERE THE HEAVIER QPF WILL FALL.
THURSDAY...AS THE LOW FILLS AND FURTHER REDUCES THE
BAROCLINICITY...THE PRECIP INTENSITY AND AMOUNTS WILL DIMINISH. SO
ADDITIONAL ACCUMULATIONS SHOULD BE RATHER LIGHT THROUGH THE DAY WITH
JUST A COUPLE MORE INCHES OF SNOW...MAINLY INTO THE TERRAIN.
THURSDAY NIGHT...WHILE THE UPPER LOW BEGINS TO SLOWLY MIGRATE
EASTWARD...ITS INFLUENCES WILL CONTINUE ACROSS THE REGION. THIS
WILL RESULT IN CHC-SCT SNOW PROBABILITIES WITH ADDITIONAL LIGHT
ACCUMULATIONS THROUGHOUT THE REGION AS TEMPERATURES WILL BE BELOW
FREEZING.
WE WILL USE A BLENDED APPROACH TO THE MOS TEMPERATURES AS THEY WERE
FAIRLY CLOSE IN VALUES.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
WE MAY STILL BE DEALING WITH A CUT-OFF UPPER LEVEL LOW FOR FRIDAY
INTO SATURDAY...BUT THE SYSTEM WILL HAVE LOST ITS BAROCLINICITY BY
THEN RESULTING IN MAINLY SCATTERED SNOW SHOWERS. THE BEST CHANCE FOR
ANY LIGHT MEASURABLE SNOWFALL WILL BE OVER THE HIGHER TERRAIN WEST
AND EAST OF THE HUDSON RIVER VALLEY...AND ESPECIALLY ACROSS THE
SOUTHERN ADIRONDACKS. OUR AREA WILL CONTINUE TO BE UNDER THE
INFLUENCE OF THE CYCLONIC FLOW ASSOCIATED WITH THIS
SYSTEM...ALTHOUGH DRIER AIR WILL GRADUALLY WORK IN FROM THE
WEST...ESPECIALLY ON SATURDAY AS WE SHOULD BE ON THE WESTERN
PERIPHERY OF THE CIRCULATION. SO WILL CONTINUE TO MENTION SLIGHT
CHANCE TO LOW CHC POPS FOR SNOW SHOWERS FRIDAY AND FRIDAY
NIGHT...DECREASING TO SLIGHT CHANCE IN THE VALLEYS FOR SATURDAY.
THERE WILL CONTINUE TO BE A SOMEWHAT BETTER CHANCE FOR A PASSING
SNOW SHOWER OVER THE HIGHER TERRAIN BOTH FRIDAY AND SATURDAY WITH
THE NORTHWEST CYCLONIC FLOW PERSISTING.
IT LOOKS LIKE DRIER WEATHER WILL FINALLY PREVAIL FOR LATE SATURDAY
INTO SUNDAY...ALTHOUGH THE DEGREE OF CLOUD COVER WILL DEPEND ON HOW
QUICKLY THE CUT-OFF LOW MOVES OUT TO SEA. THE ECMWF IS RATHER SLOW
WITH THE DEPARTURE OF THE CUT-OFF...LINGERING CYCLONIC FLOW UNTIL
SUNDAY...WHILE THE GFS HAS AN UPPER LEVEL RIDGE BUILDING IN BY LATE
SATURDAY. AGAIN...THIS WILL HAVE IMPLICATIONS ON CLOUD COVER BUT WE
ARE EXPECTING PRECIP-FREE CONDITIONS ON SUNDAY. DESPITE RISING UPPER
LEVEL HEIGHTS/TEMPS...SURFACE TEMPS ARE ONLY EXPECTED TO BE SLIGHTLY
ABOVE NORMAL DUE TO EXPECTED SHALLOW MIXING THIS TIME OF YEAR.
TRANQUIL WEATHER LOOKS TO CONTINUE INTO MONDAY...WITH HIGH PRESSURE
AT THE SURFACE AND ALOFT FIRMLY ENTRENCHED OVER THE REGION WITH GOOD
AGREEMENT BETWEEN THE ECMWF/GFS. ANOTHER SYSTEM MAY APPROACH FROM
THE WEST FOR MON NT AND TUE. WILL ADD SLIGHT CHC POPS...AS THERE IS
CONSIDERABLE UNCERTAINTY FOR EARLY NEXT WEEK WHETHER A SOUTHERN
STREAM SYSTEM PHASES WITH THE NORTHERN STREAM YET AGAIN...ALBEIT IN
A WEAKER STATE THAN THIS WEEK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A SIGNIFICANT DEVELOPING COASTAL STORM WITH MULTIPLE PRECIPITATION
TYPES WILL IMPACT THE TAF SITES THROUGH THE 24 HOUR TAF PERIOD ALONG
WITH IFR/MVFR FLYING CONDITIONS.
THIS AFTERNOON...WINTRY MIX OF SNOW...SLEET AND FREEZING RAIN AT THE
TAF SITES WILL TRANSITION TO RAIN AT ALL THE TAF SITES BY 20Z...WITH
RAIN ALREADY OCCURRING AT KALB...KPOU AND KPSF. RAIN MAY CONTINUE TO
BRIEFLY MIX WITH SLEET AT TIMES AT KGFL AND KALB AND HAVE PLACED
TEMPO GROUPS FROM 18Z TO 20Z TO ACCOUNT FOR ANY RAIN/SLEET MIX.
AFTER 20Z...LOW-LEVEL TEMPERATURES WILL BE ABOVE FREEZING TO SUPPORT
ALL RAIN AT THE TAF SITES. FLYING CONDITIONS WILL VARY BETWEEN IFR
AND MVFR DEPENDING ON PRECIPITATION INTENSITY THROUGH THE REMAINDER
OF THE AFTERNOON. WINDS WILL BE OUT OF THE NORTH AROUND 10 KNOTS
WITH OCCASIONAL GUSTS TO 20 KNOTS ESPECIALLY AT KALB AND KPSF.
TONIGHT INTO WEDNESDAY...MAINLY IFR CEILINGS ARE EXPECTED THROUGH
THE REMAINDER OF THE TAF PERIOD WITH PRIMARILY MVFR
VISIBILITIES...ALTHOUGH VISIBILITY COULD EASILY LOWER TO IFR AS
WELL DEPENDING ON HOW MUCH PRECIPITATION OCCURS OVERNIGHT. RAIN
SHOULD CONTINUE AT THE TAF SITES UNTIL 03Z-08Z...WHEN A TRANSITION
TO A RAIN/SNOW MIX IS EXPECTED TO OCCUR AT THE TAF SITES WITH KGFL
MIXING WITH SNOW CLOSER TO 03Z AND KALB AND KPSF TRANSITIONING
BETWEEN 06Z-08Z. HAVE HELD OFF ANY MENTION OF SNOW AT KPOU UNTIL 12Z
AS SURFACE TEMPERATURES LOOK TO REMAIN ABOVE FREEZING FOR MUCH OF
THE NIGHT. RAIN/SNOW SHOWERS SHOULD AFFECT THE TAF SITES AFTER 12Z
THROUGH THE REMAINDER OF THE TAF PERIOD WITH A TRANSITION TO SNOW AT
ALL TAF SITES AFTER 18Z WEDNESDAY.
WINDS WILL BE OUT OF THE NORTH AROUND 10 KNOTS WITH OCCASIONAL GUSTS
TO 20 KNOTS ESPECIALLY AT KALB AND KPSF.
OUTLOOK...
WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SN.
THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A FLOOD WATCH REMAINS IN EFFECT FOR LITCHFIELD COUNTY
CONNECTICUT...DUTCHESS COUNTY NEW YORK AND EASTERN ULSTER COUNTY
NEW YORK...FOR THIS MORNING THROUGH TONIGHT.
A COASTAL STORM WILL BRING WIDESPREAD PRECIPITATION TO THE AREA
FOR TODAY INTO TONIGHT. FOR NORTHWESTERN AND HIGH TERRAIN
AREAS...THIS PRECIPITATION WILL FALL PRIMARY AS SNOW OR A WINTRY
MIX. MEANWHILE...ACROSS SOUTHERN AND VALLEY AREAS...PRECIP WILL
BEGIN AS A PERIOD OF SNOW OR A WINTRY MIX AND TRANSITION TO RAIN.
TOTAL LIQUID EQUIVALENT VALUES WILL BE 0.50 OVER THE WESTERN
ADIRONDACKS TO NEARLY 2.00 INCHES OVER WESTERN NEW ENGLAND. WITH
MUCH OF THIS FALLING AS RAINFALL OVER LITCHFIELD COUNTY AND THE
MID HUDSON VALLEY...THERE WILL BE A LOT OF RUNOFF...ESPECIALLY
DURING LATE THIS MORNING THROUGH EARLY THIS EVENING WHEN PRECIP
WILL BE HEAVIEST. THIS RAINFALL MAY LEAD TO MINOR FLOODING OF POOR
DRAINAGE AND LOW LYING AREAS...ESPECIALLY IN AREAS WHERE THE
GROUND IS FROZEN. RISES ON RIVERS AND STREAMS ARE LIKELY...AND
MINOR FLOODING CANNOT BE RULED OUT ON THE HOUSATONIC RIVER AND
IT/S TRIBUTARIES IN NW CT.
IN ADDITION...THE STRONG COASTAL LOW IS ALLOWING FOR SOME TIDAL
FLOODING ALONG COASTAL AREAS...AND THIS COULD CAUSE A BACKUP OF
WATER ON THE HUDSON RIVER. THIS COULD LEAD TO MINOR FLOODING
DURING TIMES OF HIGH TIDE IN THE POUGHKEEPSIE AREA THIS AFTERNOON.
SOME ADDITIONAL PRECIPITATION...MAINLY IN THE FORM OF SNOW...IS
POSSIBLE FOR WEDNESDAY INTO THURSDAY...BUT AMOUNTS ARE EXPECTED TO
BE LIGHT IN AREAS THAT SEE THE HEAVIEST LIQUID PRECIP TODAY. THIS
SHOULD ALLOW WATER LEVELS TO RECEDE SLOWLY OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ001-013.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ032-033-
038>040-042-043-047-048-051-058-063-082.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ041-
049-050-052>054-059>061-083-084.
FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ064>066.
MA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-
025.
VT...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/WASULA
SHORT TERM...BGM
LONG TERM...KL/JPV
AVIATION...IRL
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1058 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SIGNIFICANT COASTAL STORM WILL IMPACT THE REGION TODAY WITH
WINTRY PRECIPITATION AND HEAVY RAIN...ALONG WITH STRONG TO
DAMAGING WINDS. LEFTOVER LIGHT SNOW AND RAIN SHOWERS WILL PERSIST
WEDNESDAY AND THURSDAY. SLOW IMPROVEMENT IS EXPECTED FRI INTO THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
1040 AM UPDATE...
TEMPS HAVE BEEN SLOWLY BUT STEADILY RISING ACROSS E MA/RI/NE CT
THROUGH 15Z...BUT HOLDING RIGHT AROUND FREEZING FROM THE INTERIOR
MERRIMACK VALLEY THROUGH CENTRAL AND NW MA. NOTING THAT TEMPS HAVE
BEEN WARMING ALOFT WITH RATHER STRONG LOW LEVEL INVERSION AS SEEN
ON 12Z KOKX SOUNDING /UP TO +5C AT 866 MB AND FREEZING LEVEL UP TO
6500 FT/...SO TENDING TO MIX DOWN WITH THE AREA OF HEAVY RAINFALL
MOVING INTO S COASTAL AREAS. THIS WILL HELP TEMPS RISE EVEN ACROSS
INLAND AREAS AS THE SLUG OVER HEAVY PRECIP MOVES IN.
NOTING 1005 HPA LOW PRES JUST NE OF THE DELMARVA PENINSULA AT
15Z...WHICH APPEARS PRETTY MUCH ON TRACK THOUGH TUCKED A BIT
CLOSER TO THE COAST.
NOTING REPORTS OF 0.75 TO 1 INCH/HR RAINFALL RATES ACROSS S CT AND
LONG ISLAND OVER THE LAST HOUR OR TWO. THIS...ALONG WITH GUIDANCE
FROM NESDIS SATELLITE PRECIP ESTIMATE REPORTING A MAX PWAT PLUME
OF 1.65 INCHES WELL S OF LONG ISLAND EARLIER THIS MORNING. VERY
COLD CLOUD TOPS ALSO NOTED S OF LONG ISLAND. DRY SLOT NOTED ON NE
REGIONAL 88D RADAR E OF KACY...WHICH WILL SLOWLY SHIFT N-NE DURING
THE DAY. ALSO NOTED 06Z GFS OP RUN SUGGESTING UP TO 1.5 TO 2 INCH
RAINFALL RATES IN TWO 6-HOUR PERIODS BETWEEN NOW AND 00Z MOVING
ACROSS RI/E MA. CONSIDERING THE NESDIS OBSERVATIONS...FELT THIS
WAS NOT TOO BAD SO UPDATED TO INCREASE PRECIP AMOUNTS. THIS GIVES
STORM TOTAL PRECIP OF 2.5 TO 3.5 INCHES...WHICH MAY LEAD TO
LOCALIZED URBAN AND POOR DRAINAGE FLOODING ACROSS RI/E MA.
HAVE UPDATED FORECAST TO INCLUDE HEAVY RAINFALL MENTION TO THE
FORECAST. WILL ALSO MONITOR FOR THE CHANCE OF ANY THUNDER THAT MAY
NEED TO BE ADDED ACROSS S COASTAL RI/MA. NOTING C/G LIGHTNING TO
THE E OF THE DRY SLOT. ALSO UPDATED TEMPS/DEWPTS TO BRING
CONDITIONS CURRENT. REMAINDER OF FORECAST IN PRETTY GOOD SHAPE.
PREVIOUS DISCUSSION...
* SYNOPTICALLY...
PRESENT OFFSHORE LOW OFF THE MID-ATLANTIC CONUS BECOMES USURPED BY
AN AMPLIFYING TROUGH DIGGING THROUGH THE E-CONUS. ACROSS A REGION OF
FAVORABLE BAROCLINICITY / ATTENDANT DYNAMICS / STRONG FORCING AND
DEEP-LAYER ASCENT YIELDS A RAPIDLY DEEPENING AREA OF LOW PRESSURE
OFF THE DELMARVA PENINSULA THIS MORNING LIFTING N INTO S NEW ENGLAND
BY EVENING. THE LOW BECOMES STALLED AND CUTOFF FROM THE MEAN FLOW UP
AGAINST HIGH PRESSURE ON NEARLY ALL SIDES AS WE GO INTO THE WEEK.
* HEAVY RAIN AND FLOODING...
AS THE LOW DEEPENS...EXPECT DECENT LOW-LEVEL TROWALING OF THE
WARM-CONVEYER-BELT BENEATH THE RRQ/LFQ OF ATTENDANT UPPER-LEVEL
JET AXES. COMBINATION OF THE CONVERGENT LEADING NOSE OF ISENTROPIC
UPSLOPE LENDING TO THE TIGHTENING OF THE THERMAL GRADIENT AGAINST
NEIGHBORING HIGH PRESSURE YIELDING STRONG FRONTOGENETICAL FORCING
IN A REGION OF MINOR -EPV INSTABILITY BENEATH AFOREMENTIONED DEEP
LAYER ASCENT LIKELY TO RESULT IN A ROUGHLY W-E BANDING SETUP OF
HIGHER WSR-88D RETURNS WITHIN A WIDESPREAD COMMA-SHAPED PRECIP
FIELD ALONG THE N-PERIPHERY OF THE H85 LOW WITH THE FRONT-END
THUMP OF PRECIP ANTICIPATED AROUND MIDDAY AND PERSISTING INTO
EARLY EVENING.
WILL EXPAND THE FLOOD WATCH TO INCLUDE CAPE COD AND NANTUCKET.
WITH HEIGHT OF THE E-NE WINDS AND HEAVY RAIN CONCURRENT WITH
TIMING OF HIGH TIDE CENTERED AROUND 1 PM BELIEVE SURGE ALONG WITH
BUILDING WAVE HEIGHTS /SEE THE MARINE DISCUSSION BELOW FOR MORE
DETAILS/ WILL RESULT IN POOR-DRAINAGE ISSUES FOR COASTAL
COMMUNITIES. ANTICIPATE DRAINS TO BACK-UP BECOMING OVER-TOPPED
RESULTING IN SUSCEPTIBLE LOW- LYING AND POOR-DRAINAGE AREAS TO
BECOME FLOODED.
AM ALSO CONCERNED FOR EVEN THOSE COMMUNITIES WITHIN THE COASTAL
PLAIN IN VICINITY OF RIVERS THAT ARE INFLUENCED BY THE TIDE /I.E.
TAUNTON RIVER...LOWER CONNECTICUT/. COULD ALSO SEE SOME EXACERBATED
FLOOD ISSUES FOR THESE AREAS.
OTHERWISE REMAINDER OF THE FLOOD WATCH REMAINS IN PLACE. PWATS OF
1.25-INCHES FORECAST /ROUGHLY +2 STANDARD DEVIATIONS ABOVE-NORMAL/
AND FORECAST RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS ANTICIPATED. GROUND IS PRETTY SOLID /IMPERVIOUS/ THUS EXPECT
MOST OF THE RAINFALL TO BECOME RUNOFF. MAJORITY OF MAINSTEM RIVERS
OVER THE INTERIOR SHOULD BE ABLE TO HANDLE THE RAIN...SO CONCERNS
LIE IN THE REALM OF URBAN / POOR DRAINAGE FLOODING...ESPECIALLY IF
DRAINS ARE STILL LEAF-CLOGGED. BIGGEST AREA OF CONCERN IS WITHIN THE
METRO-AREA CORRIDORS...ESPECIALLY BOSTON-PROVIDENCE. MAY NEED TO
EXPAND THE WATCH ACROSS N-CENTRAL AND NW MA PENDING THE TIMING AT
WHICH WINTRY-PRECIP TYPES TRANSITION TO RAIN.
* WINTRY PRECIPITATION...
OUTCOMES DEPENDENT ON THERMAL FIELDS ALOFT...WHERE AROUND H925-H85
BY MORNING CONDITIONS ARE WARMING CONSIDERABLY UP AGAINST COLDER AIR
AND HIGH PRESSURE SITUATED N/W. A SW-NE FREEZING LINE AROUND NW-CT
INTO S NH INITIALLY MODIFIES NW AS THE LOW DEEPENS RESULTING IN THE
INCREASE OF THE SE WARM-MOIST-CONVEYER-BELT. EXPECT THICKNESSES
TO GRADUALLY RISE DURING THE HEIGHT OF THE EVENT INTO EVENING.
AT THE SURFACE...AREAS BELOW FREEZING ERODE WITH INCREASING ONSHORE
E/NE-WINDS DURING THE MORNING /MORE ON THAT LATER/. UNCERTAINTY
CONTINUES WITH 09.0Z HIGH-RES MODELS DIFFERING IN TIMING OF EROSION.
AS MENTIONED IN PRIOR DISCUSSIONS...FOR AREAS THAT ARE WITHIN OR
ON THE CUSP OF BELOW-FREEZING TEMPERATURES BY 1-2C...LINGERING AN
HOUR OR TWO MORE OR LESS CAN MAKE ALL THE DIFFERENCE WITH REGARDS
TO WINTER-WEATHER HEAD-LINES. H975-925 AGEOSTROPHIC FLOW IS
NOTABLY PERSISTENT AND STRONG OUT OF THE W AS THE LOW INTENSIFIES
TOWARDS S NEW ENGLAND. BUT NOT MUCH OF A N-COMPONENT NOR FROM
ARCTIC-SOURCE REGIONS...SO BELIEVE THIS WILL DO LITTLE TO MAINTAIN
/ PERSIST COLD AIR OVER THE REGION AGAINST STRONG ONSHORE E-FLOW.
WILL GO CLOSE TO THE NEAR-TERM HIGH-RES GUIDANCE WHILE INCORPORATING
THE WRF-NMM WITH REGARDS TO THERMAL FIELDS...WHICH ARE HANDLING THE
SURFACE TEMPERATURES DECENTLY. PREFERENCE TO THE 09.0Z ECMWF IS ALSO
GIVEN ESPECIALLY WHEN EVALUATING H100-H85 THICKNESSES. ONLY WRF-ARW
AND RAP LEAN ON THE WARM SIDE OF THE GUIDANCE OVER ALL OTHERS.
ALSO WILL GO WITH A TOP-DOWN APPROACH TOWARDS PRECIPITATION-TYPE
THAT INCORPORATES THE INCREASING MOISTURE FROM THE S WITHIN OR
ABOVE THE DENDRITIC GROWTH ZONE REGION.
SO OVERALL...EXPECTING THE GRADUAL EROSION OF THE COASTAL-FRONT WITH
INCREASING ONSHORE E-FLOW. PUSH OF WARMER AIR ALOFT AHEAD OF THE
DEEPENING LOW WILL RESULT IN PRECIP-TYPE TRANSITION FAIRLY QUICKLY
TO A SLEET / FREEZING RAIN MIX. THIS HAS SUBSEQUENTLY BUMPED DOWN
SNOWFALL AMOUNTS RESULTING IN A RANGE OF 2-4 INCHES ACROSS NW MA.
MOST OF THE REGION CHANGES OVER TO RAIN BY LATE MORNING INTO MIDDAY
WITH ONLY THE HIGHER ELEVATIONS OF THE BERKSHIRES CONTINUALLY UNDER
THE THREAT OF FREEZING RAIN.
HAVE DROPPED WINTER-STORM WATCHES AND REPLACED WITH WINTER WEATHER
ADVISORIES. HAVE TRIMMED THE EASTERN-EXTENT WITH EROSION OF THE
COASTAL FRONT AND THE SURGE OF WARMER AIR ONSHORE. AGAIN...THE
THERMAL FIELDS DISCUSSION ABOVE GIVE AN INDICATION OF PREFERRED
MODEL GUIDANCE. SHOULD SEE WINTER WEATHER HEADLINES DROP MAINLY
AROUND THE MIDDAY HOURS.
MID-LEVEL DRY-SLOT WRAPPING INTO A DEVELOPING OCCLUSION BEGINNING
TUESDAY EVENING SHOULD RESULT IN A LULL OF PRECIPITATION AS WE GO
INTO WEDNESDAY MORNING.
* STRONG TO DAMAGING WINDS...
NOTING E-WINDS 1-2 KFT AGL WILL BE AROUND 55 MPH AROUND THE MIDDAY
INTO AFTERNOON HOURS...THE PRESENCE OF WARMER AIR ALOFT LENDING TO
AN INVERSION JUST ABOVE THE SURFACE MAKES IT DIFFICULT TO CONSIDER A
HIGH WIND WARNING. THIS DESPITE WARMER AIR WIGGLING ITS WAY UP FROM
THE S AT THE SURFACE...AND A WARMER OCEAN /THOUGH NOW AROUND THE LOW-
50S/. BOUNDARY-LAYER MIXING WILL BE LIMITED. HIGH-END WIND ADVISORY
CRITERIA IS EXPECTED...BUT DO NOT EXPECT WIDESPREAD GUSTS EXCEEDING
HIGH WIND WARNING CRITERIA. THUS WENT WITH THE WIND ADVISORY.
COULD PRECIPITATION-DRAG PROCESSES BRING FASTER MOMENTUM TO THE
SURFACE? YES...IT IS QUITE POSSIBLE...EVEN IF THUNDERSTORMS ARE IN
THE MIX WHICH IS IN THE FORECAST FOR THE FAR SE-WATERS ADJACENT TO
THE CAPE AND ISLANDS. HAVE GONE WITH THE HEADLINES THAT CONVEY THE
HIGHEST CONFIDENCE.
* COASTAL FLOODING...
SEE TIDES/COASTAL FLOODING SECTION BELOW FOR DETAILS.
&&
.SHORT TERM /WEDNESDAY/...
SEE LONG TERM SECTION BELOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* LINGERING RAIN/SNOW SHOWERS INTO THU AS CLOSED LOW SLOWLY EXITS
* IMPROVING CONDITIONS FRI INTO THIS WEEKEND
DECENT MODEL AGREEMENT BOTH AT THE SURFACE AND ALOFT WEDNESDAY
INTO FRIDAY. MORE SIGNIFICANT DIFFERENCES ARISE FRIDAY NIGHT INTO
EARLY NEXT WEEK. AS SUCH...FAVORED A CONSENSUS BLEND TO UPDATE
THIS PORTION OF THE FORECAST. THIS WAS TO SMOOTH OVER THE MINOR
DIFFERENCES INTO FRIDAY...AS WELL AS MINIMIZE ERROR AFTER THAT
POINT.
CLOSED LOW WILL BE SLOW TO EXIT NEW ENGLAND...AND 09/00Z GUIDANCE
MODELS CONTINUE TO SHOW A DEEP UPPER LOW OVER NORTHERN NEW ENGLAND
FINALLY MOVING OUT TO SEA SATURDAY NIGHT. ONE OF THE PRIMARY
ISSUES WITH THIS FORECAST WILL BE THE AMOUNT OF MOISTURE
AVAILABLE. THINKING THERE WILL BE ENOUGH TO KEEP SKIES MOSTLY
CLOUD INTO FRIDAY NIGHT. HOW MUCH WILL BE LEFTOVER TO US IN
GENERATING PRECIPITATION IS ANOTHER MATTER. CONTINUED THE PREVIOUS
FORECAST OF A GRADUAL DRYING OUT PROCESS FRIDAY INTO SATURDAY.
HIGH PRESSURE SHOULD BE IN CONTROL OF OUR WEATHER SUNDAY INTO
MONDAY.
NEAR OR SLIGHTLY BELOW NORMAL TEMPERATURES EXPECTED THROUGH THIS
PERIOD.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY MORNING/...
12Z UPDATE...
TODAY INTO TONIGHT...MODERATE CONFIDENCE.
MIX OF MVFR-IFR CIGS / VSBYS WITH MAINLY +RA. AN ISOLATED TSRA IS
POSSIBLE FOR FAR SE-COASTAL TERMINALS. OTHERWISE GRADUAL EROSION
TO N/W OF FZRA/PL/SN INTO THE EARLY-AFTERNOON HOURS DURING WHICH
TIME WINDS WILL INCREASE OUT OF THE E WITH STRONGEST GUSTS ALONG
THE E-SHORELINE MAINLY AROUND 40 KT WITH LOCALLY HIGHER GUSTS UP
TO 50 KT. WILL ALSO SEE AN ACCOMPANYING LLWS THREAT WITH WINDS
AROUND 2 KFT AGL OUT OF THE E AROUND 60 KTS.
KBOS TERMINAL...MODERATE CONFIDENCE.
FEEL CONFIDENT WITH TRENDS BUT NOT SO MUCH WITH SPECIFICS. HIGH
CONFIDENCE OF CONTINUED +RA WITH INCREASING E-WINDS. GUSTS UP TO
40 KT ANTICIPATED TOWARDS THE MIDDAY HRS. WIND ADVISORY LENDING
TO ISSUANCE OF AIRPORT WEATHER WARNING.
KBDL TERMINAL...MODERATE CONFIDENCE.
FZRA PERSISTING INTO THE EARLY-MORNING HOURS...THEN CHANGING OVER
TO RAIN. NOT ABSOLUTELY CERTAIN ON TIMING BUT CONFIDENT WITH
TRENDS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE. MVFR/IFR IN
SCATTERED RAIN OR SNOW SHOWERS.
FRIDAY...MODERATE CONFIDENCE. MVFR IN ISOLATED RAIN/SNOW SHOWERS.
SATURDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TONIGHT/...HIGH CONFIDENCE.
1030 AM UPDATE...
THROUGH THIS AFTERNOON NOTING SEAS HAVE INCREASED TO 10-15 FT ON
THE OUTER WATERS AND EVEN PUSHING INTO MASS BAY ON THE E FETCH.
HAVE UPDATED TO INCREASE THE SEAS TO AT LEAST THESE LEVELS. EXPECT
STRONGEST WINDS TO PUSH INTO THE WATERS. GUSTS UP TO 33 KT REPORTS
AT BUOY 44020 /NANTUCKET SOUND/ AND 31 KT AT BOTH MASS BAY BUOYS
WITH 35 KT GUSTS AT THE BUZZARDS BAY TOWER AT 15Z. FORECAST
THROUGH TODAY PRETTY MUCH ON TRACK.
PREVIOUS DISCUSSION...
HAVE GONE WITH STORM WARNINGS FOR THE OUTER WATERS WITH THE
EXPECTATION OF GUSTS AROUND 45-50 KT. BUT GREATER CONFIDENCE OF
THE INNER WATERS REACHING HIGH-END GALE WARNING CRITERIA
PERMITTED THE DISCONTINUING OF THE STORM WATCH. CAN NOT RULE OUT
AN ISOLATED GUST UP TO 50 KTS OVER THE INNER WATERS...BUT WITH IT
NOT ANTICIPATED TO BE WIDESPREAD...KEPT WITH GALE WARNINGS.
STRONGEST E-WINDS OCCURRING TOWARDS THE MIDDAY AND CONTINUING INTO
THE EARLY EVENING HOURS.
SEAS BUILDING 15 TO 20 FEET WITH INCREASING E WINDS AHEAD OF A
DEEPENING AREA OF LOW PRESSURE OF THE DELMARVA PENINSULA PRESENTLY
AS IT LIFTS N INTO S NEW ENGLAND TOWARDS THIS EVENING. EXPECT
ACCOMPANYING HEAVY RAIN WHICH WILL YIELD VISIBILITY RESTRICTIONS
ON THE WATERS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
SMALL CRAFT ADVISORIES WILL LIKELY NEED TO CONTINUE THROUGH
THURSDAY NIGHT ACROSS THE OCEAN-EXPOSED COASTAL WATERS...MAINLY
DUE TO ROUGH SEAS. THERE COULD ALSO BE SOME WEST/SOUTHWEST GUSTS
UP TO 25 KT AS WELL. ALSO SHOULD SEE LEFTOVER SCATTERED RAIN/SNOW
SHOWERS.
FRIDAY INTO SATURDAY...MODERATE CONFIDENCE.
SLOW IMPROVEMENT CONTINUES WITH DIMINISHING WINDS AND SEAS. SEAS
SHOULD FINALLY DROP BELOW 5 FT ACROSS ALL BUT THE OUTERMOST
COASTAL WATERS FRI EVENING...THEN REMAIN BELOW SMALL CRAFT
ADVISORY THRESHOLDS ACROSS ALL WATERS SATURDAY.
&&
.HYDROLOGY...
UPDATED 950 AM TUE...
EXPANDED FLOOD WATCH TO INCLUDE MARTHAS VINEYARD AND BLOCK ISLAND.
ALTHOUGH RAINFALL TOTALS WILL BE 1.5 TO 2.5 INCHES...COMBINATION
OF RAINFALL AND RISING TIDE THROUGH EARLY AFTERNOON MAY LEAD TO
SIGNIFICANT FLOODING ESPECIALLY ON E/SE SHORELINES. BUOYS
REPORTING 5-6 FT SEAS ON NANTUCKET SOUND AND 11 FT SE OF BLOCK
ISLAND. SIMILAR SITUATION FOR CAPE COD AND NANTUCKET.
MAIN CONCERN CONTINUES TO BE POTENTIAL FOR SIGNIFICANT URBAN
FLOODING...ESPECIALLY IN RI AND E MA. ALREADY SEEING RAINFALL
RATES OF NEARLY 2 INCHES PER HOUR ACROSS SOUTHERN CT /KSNC ASOS/
WHICH WILL TRANSLATE OVER OUR AREA BY EARLY AFTERNOON. SOME OF THE
URBAN HOT SPOTS SUCH AS PEABODY...FALL RIVER...NEW BEDFORD AND
CRANSTON MAY BE ESPECIALLY VULNERABLE TO FLOODING. TOTALS OF 2 TO
3 INCHES ARE EXPECTED WITH A FEW 3 OR 4 INCH TOTALS NOT OUT OF
QUESTION NEAR I-95 CORRIDOR.
FLOODING OF SMALL STREAMS IS ALSO A POSSIBILITY...BUT WORST CASE
WOULD BE FOR MINOR FLOODING IF TOTALS EXCEED 3 INCHES.
NOT EXPECTING FLOODING OF LARGER RIVERS. LATEST NERFC GUIDANCE
BRINGS LOWER CT RIVER AT MIDDLE HADDAM TO ACTION STAGE...WHICH IS
PRIMARILY BASED ON SURGE OF 2 FT INTO LOWER CT RIVER. WE MAY ALSO
SEE SIMILAR SURGE ALONG PAWCATUCK RIVER NEAR WESTERLY RI WHICH
COULD BRING RISES SLIGHTLY HIGHER THAN CURRENTLY FORECAST.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY CONTINUES FOR EASTERN MA. COMBINATION OF
WINDS / SEAS / SURGE OF AROUND 1.5 TO 2 FEET DURING THE MIDDAY
HIGH-TIDE YIELDS THE LIKELIHOOD OF OBSERVING MINOR COASTAL
FLOODING AND BEACH EROSION FOR E-FACING SHORELINES WHERE SEAS OF
12 TO 15 FEET ARE POSSIBLE.
AS NOTED IN THE HYDROLOGY PORTION ABOVE...LOCAL STREAMS AND
TRIBUTARIES EMPTYING INTO THE SEA COULD SEE BACK-FILLING ISSUES AS
THE HEAVY RAIN IS ANTICIPATED DURING THE TIME OF HIGH-TIDE. COULD
SEE FLOODING ISSUES EXACERBATED FOR EASTERN MA SHORELINE
COMMUNITIES.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ002>004.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ002>004.
MA...FLOOD WATCH THROUGH LATE TONIGHT FOR MAZ005>007-011>024.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR MAZ007-014>016-
019>024.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ007-015-016-019-022-024.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MAZ005-006-011-012.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ003-004-009-010-026.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
MAZ002-008.
RI...FLOOD WATCH THROUGH LATE TONIGHT FOR RIZ001>008.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR RIZ006>008.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ230>234-251.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ235>237.
STORM WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...BELK/EVT
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/EVT
HYDROLOGY...STAFF
TIDES/COASTAL FLOODING...STAFF
AREA FORECAST DISCUSSION
NWS ALBANY NY
1016 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SLOW MOVING COASTAL STORM WILL BRING A VARIETY OF
WINTER WEATHER TO THE REGION FOR TODAY INTO TONIGHT. WHILE MANY
VALLEY AND EASTERN AREAS WILL SEE A TRANSITION OF A WINTRY MIX TO
RAIN...THE PRECIPITATION WILL BE MAINLY SNOW ACROSS THE CATSKILLS
AND ADIRONDACKS...WITH A MODERATE TO HEAVY ACCUMULATION POSSIBLE IN
THESE HIGH TERRAIN AREAS. WITH THE STORM REMAINING CLOSE TO THE
REGION...SOME ADDITIONAL RAIN AND SNOW WILL OCCUR WEDNESDAY INTO
THURSDAY AS WELL...WITH SOME ADDITIONAL SNOW ACCUMULATION POSSIBLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1014 AM EST...A 1004 HPA COASTAL LOW CONTINUES TO BE JUST
E/SE OF THE DELMARVA REGION THIS MORNING ACCORDING TO THE LATEST
MSAS MSLP ANALYSIS. THE BEST 3-HR MSLP /5-6 HPAS/FALLS ARE NORTH
OF THE SFC CYCLONE. THE LATEST KENX VWP SHOWS A STRONG E/SE LLJ
IN THR 3-6 KFT AGL LAYER OF 25-35 KTS. THIS PRONOUNCED LLJ HAS
YIELDED SOME SIGNIFICANT DOWNSLOPING OFF THE SRN GREENS...NRN
BERKS...AND THE NRN TACONICS. THE PCPN IS FINALLY TRYING TO EXPAND
NORTHWARD INTO THE UPPER HUDSON REGION...AND SRN VT. THE SRN DACKS
ARE ALSO SLOWLY...BUT FINALLY...GETTING INTO A THE PCPN SHIELD. THE
LLJ CONTINUES TO INTENSIFY JUST S/SE OF THE REGION...AND THE BEST
QG LIFT WITH THE EARLY PHASES OF THE STORM IS OVER COASTAL SRN NEW
ENGLAND AND LONG ISLAND AT THIS TIME. THE STRONG LIFT WILL IMPACT
THE REGION IN THE AFTERNOON.
PTYPES HAVE FAVORED SLEET AND FREEZING RAIN THIS MORNING. THE 12Z
KALY SOUNDING INDICATES A SLEET PROFILE. SOME HAS OCCURRED IN THE
CAPITAL DISTRICT WITH THE FREEZING RAIN/DRIZZLE. SOME ICE REPORTS
HAVE COME IN...WITH PERU IN THE S-CNTRL BERKS HAVING TWO TENTHS OF
AN INCH. THE COLUMN CONTINUES TO WARM WITH KPOU ABOVE FREEZING
WITH LIGHT RAIN...WHICH SHOULD TRANSITION TO MDT-HVY RAIN OVER THE
NEXT HOUR OR TWO. WE WILL LET THE ADVISORY RUN UNTIL 11 AM...FOR
ERN ULSTER/DUTCHESS/LITCHFIELD COUNTIES...AS SOME TEMPS ARE
SLIGHTLY BELOW OR ARE HOVERING NEAR THE FREEZING MARK.
FURTHER NORTH...THE DOWNSLOPING HAS ALLOWED KPSF/KAQW/KDDH TO
ALLOW JUMP ABOVE FREEZING INTO THE MID AND U30S. SOME WET BULB
COOLING SHOULD LOWER THESE TEMPS CLOSER TO FREEZING. PTYPES WERE
ATTEMPTED TO BE ADJUSTED ACCORDING THE HOURLIES AND A GFS/ECMWF
BLEND. MIXED PCPN WILL LIKELY LINGER FOR THE CAPITAL
REGION...N-CNTRL TACONICS...BERKSHIRES...AND SRN VT INTO THE AFTERNOON BEFORE
CHANGING TO RAIN. FURTHER NORTH AND WEST WILL HAVE THE BEST CHC OF
SNOW...WITH A LIGHT MIXED TO SLEET/FREEZING RAIN/RAIN...BEFORE
GOING BACK TO SNOW OVERNIGHT...BUT THIS WILL CONTINUE TO BE FINED
TUNED.
SOME OF THE PREVIOUS DISCUSSION FOLLOWS FOR THIS AFTERNOON AND
TONIGHT...
THERE WILL BE A SHARP CUTOFF BETWEEN SNOW VS. WINTRY MIX VS. RAIN.
THE 3KM HRRR SHOWS THAT SNOW SHOULD ACCUMULATE ACROSS THE
CATSKILLS/HELDERBERGS AND POINTS WESTWARD INTO THIS AFTERNOON.
FURTHER NORTH...THE PRECIP WILL EXPAND INTO THE WRN MOHAWK VALLEY
AND ADIRONDACKS BY THE EARLY AFTN HOURS. PRECIP LOOKS TO BE MAINLY
SNOW FOR THE MOHAWK VALLEY/ADIRONDACKS...BUT WILL LIKELY MIX FOR
THE SARATOGA/GLENS FALLS AREA. EVEN UP THERE...A CHANGEOVER TO
RAIN LOOKS TO OCCUR DURING THE AFTN HOURS...AS WARM AIR...BOTH AT
THE SFC AND ALOFT...WILL BE MOVING INTO THE AREA.
FURTHER EAST...THE PRECIP WILL CHANGE TO A WINTRY MIX FOR SOUTHERN
VT/BERKSHIRES AS WELL...EVEN ACROSS THE HIGH TERRAIN...AS WARM
AIR ALOFT OF NEARLY 3 DEGREES C MOVES OVER THE AREA FROM THE EAST.
SOME SNOW/SLEET WILL LIKELY ACCUMULATE BEFORE THE CHANGEOVER...BUT
THE CHANGEOVER WILL PREVENT WARNING LEVEL SNOW FROM OCCURRING. SOME
STRONG WINDS ARE POSSIBLE ACROSS THE SRN GREENS...TACONICS AND
BERKSHIRES...WITH SOME GUSTS OF 25-40 MPH POSSIBLE. THE FULL
BRUNT OF THE LOW LEVEL JET DOESN/T LOOK LIKE IT WILL BE ABLE TO
MIX DOWN DUE TO STABLE LOW LEVELS...BUT SOME GUSTS ARE STILL
POSSIBLE...ESP IN AREAS THAT CHANNEL E-SE FLOW WELL. WE WILL
CONTINUE TO MENTION THIS WIND THREAT IN OUR HWO STATEMENT.
AS THE BEST ISENTROPIC LIFT SHIFTS NORTH AND EAST OF THE REGION
THIS EVENING...STEADY PRECIP WILL START TO SHUT OFF ACROSS OUR
AREA. THE SFC LOW WILL BE MEANDERING OVER THE NYC/LONG ISLAND
AREA...AND THE 500 HPA LOW WILL BECOME CUTOFF OVER THE DELMARVA
AREA. AS A RESULT...SOME ADDITIONAL ON AND OFF PRECIP WILL OCCUR
OVERNIGHT DUE TO THE PVA/CYCLONIC FLOW...BUT IT WILL NOT BE
STEADY OR HEAVY. THERE WILL STILL BE SOME ABOVE FREEZING TEMPS
ALOFT...AND THERE MAY EVEN BE A LACK OF ICE NUCLEI IN THE
CLOUDS...AS THE BEST DEEPER AND COLDER CLOUD TOPS SHIFT AWAY FROM
THE AREA. BECAUSE OF THIS...SOME FREEZING RAIN/DRIZZLE MAY
OCCUR...ALONG WITH SOME BURSTS OF SNOW/RAIN/SLEET AS WELL. TEMPS
LOOK TO HOLD STEADY IN THE LOW TO MIDDLE 30S ACROSS THE ENTIRE
REGION.
BECAUSE OF ALL OF THIS...WINTER STORM WARNINGS WERE NOT ISSUED
OUTSIDE THE CATSKILLS/MOHAWK AND SCHOHARIE VALLEY/ADIRONDACKS
BECAUSE WARNING LEVEL SNOWFALL /7 INCHES IN 12 HOURS OR 9 INCHES
IN 24 HOURS/ IS NOT EXPECTED. STILL...A WINTRY MIX...EVEN THOUGH
IT WILL GO OVER TO RAIN...WILL MAKE FOR HAZARDOUS TRAVEL IN THE
CAPITAL REGION/GLENS FALLS AND SARATOGA AREAS/BERKSHIRES/SOUTHERN
VT/...AND THIS IS WHY THE WINTER WEATHER ADVISORY HAS BEEN ISSUED
FOR THESE LOCATIONS. SNOW ACCUMULATION IN THESE AREAS WILL VARY
BASED ON ELEVATION...WITH JUST UP TO A FEW INCHES IN THE VALLEY
AREAS...AND 2 TO 6 INCHES ACROSS THE HIGH TERRAIN. JUST A COATING
TO AN INCH OF SNOW/SLEET/ICE IS EXPECTED FOR THE
POUGHKEEPSIE/KINGSTON AREA AND NW CT...AS PRECIP SHOULD QUICKLY GO
OVER TO RAIN THERE THIS MORNING. HOWEVER...THE FLOOD WATCH REMAINS
IN EFFECT...AS HEAVY RAINFALL MAY LEAD TO SOME FLOOD CONCERNS. SEE
OUR HYDRO DISCUSSION FOR MORE DETAILS ON THIS THREAT.
MEANWHILE... 6 TO 12 INCHES LOOK TO ACCUMULATE IN THE
CATSKILLS...HELDERBERGS...MOHAWK AND SCHOHARIE VALLEYS...AND
ADIRONDACKS. EVEN IN THESE AREAS...SOME SLEET/FREEZING RAIN IS
POSSIBLE AT TIMES...AND VALLEYS WILL BE ON THE LOWER END OF THE
RANGE...WITH THE HIGHEST AMOUNTS IN THE HIGH PEAKS OF THE
CATSKILLS IN THE GREENE COUNTY...AND IN THE HIGHEST PEAKS OF THE
SRN ADIRONDACKS OF WARREN COUNTY. THE SNOW WILL BE RATHER
WET...AND THIS MAY MAKE FOR SOME POWER OUTAGES/DOWNED TREE
LIMBS...ESP CONSIDERING THAT STRONG NORTH WINDS ARE EXPECTED.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
A NEARLY VERTICALLY STACKED LOW OVER NEW ENGLAND WILL KEEP OUR
WEATHER UNSETTLED THROUGH THE SHORT TERM PERIOD.
WHILE DIFFICULT TO ASCERTAIN WHAT WAVE/S/ WILL TRIGGER ADDITIONAL
PRECIPITATION...MOISTURE WILL WRAP IN OFF THE ATLANTIC TO KEEP THE
HIGH PROBABILITIES IN THE FORECAST. THE BEST LOCATIONS WILL BE
ALONG THE I90 CORRIDOR AND POINTS NORTHWARD. AS FOR THERMAL
PROFILES...WE WILL BE COOLING DOWN THE COLUMN WHERE MOST OF THIS
PRECIPITATION WILL BE IN THE FORM OF SNOW. THERE WILL BE SOME
RAIN/SNOW MIXTURE INTO THE VALLEY LOCATIONS DURING THE LATE MORNING
INTO THE MID AFTERNOON HOURS. THE BEST CHANCE FOR ADDITIONAL
ACCUMULATIONS WILL BE INTO THE HIGHER TERRAIN. AS FOR THE
SPECIFIC...
WEDNESDAY...LATEST TRENDS IN THE MODEL GUIDANCE POINT TOWARD A MORE
SIGNIFICANT SURGE OF MOISTURE OFF THE ATLANTIC AS THE MAIN UPPER LOW
REMAINS JUST OFF THE JERSEY SHORE. MOISTURE ADVECTION AND HIGHER
THETA-E /TROWAL/ BACK INTO PORTIONS OF EASTERN NEW YORK AND WESTERN
NEW ENGLAND. SPECIFIC HUMIDITIES REMAIN RATHER HIGH OF 3-4 G/KG SO
WHERE IT DOES SNOW...WE COULD SEE ADDITIONAL ACCUMULATIONS OF SNOW.
PER THE LATEST NCEP MODEL SUITE AND 00Z ECMWF...THIS SEEMS TO LINE
UP FOR OUR NORTHERN HALF OF THE CWFA. ADDITIONAL FINE TUNING WILL
TAKE PLACE AS PER CSTAR RESEARCH...THESE UPPER LOWS ARE QUITE
PROBLEMATIC WITH PROVIDING SPECIFICS WHERE THE HEAVIER QPF WILL FALL.
THURSDAY...AS THE LOW FILLS AND FURTHER REDUCES THE
BAROCLINICITY...THE PRECIP INTENSITY AND AMOUNTS WILL DIMINISH. SO
ADDITIONAL ACCUMULATIONS SHOULD BE RATHER LIGHT THROUGH THE DAY WITH
JUST A COUPLE MORE INCHES OF SNOW...MAINLY INTO THE TERRAIN.
THURSDAY NIGHT...WHILE THE UPPER LOW BEGINS TO SLOWLY MIGRATE
EASTWARD...ITS INFLUENCES WILL CONTINUE ACROSS THE REGION. THIS
WILL RESULT IN CHC-SCT SNOW PROBABILITIES WITH ADDITIONAL LIGHT
ACCUMULATIONS THROUGHOUT THE REGION AS TEMPERATURES WILL BE BELOW
FREEZING.
WE WILL USE A BLENDED APPROACH TO THE MOS TEMPERATURES AS THEY WERE
FAIRLY CLOSE IN VALUES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
WE MAY STILL BE DEALING WITH A CUT-OFF UPPER LEVEL LOW FOR FRIDAY
INTO SATURDAY...BUT THE SYSTEM WILL HAVE LOST ITS BAROCLINICITY BY
THEN RESULTING IN MAINLY SCATTERED SNOW SHOWERS. THE BEST CHANCE FOR
ANY LIGHT MEASURABLE SNOWFALL WILL BE OVER THE HIGHER TERRAIN WEST
AND EAST OF THE HUDSON RIVER VALLEY...AND ESPECIALLY ACROSS THE
SOUTHERN ADIRONDACKS. OUR AREA WILL CONTINUE TO BE UNDER THE
INFLUENCE OF THE CYCLONIC FLOW ASSOCIATED WITH THIS
SYSTEM...ALTHOUGH DRIER AIR WILL GRADUALLY WORK IN FROM THE
WEST...ESPECIALLY ON SATURDAY AS WE SHOULD BE ON THE WESTERN
PERIPHERY OF THE CIRCULATION. SO WILL CONTINUE TO MENTION SLIGHT
CHANCE TO LOW CHC POPS FOR SNOW SHOWERS FRIDAY AND FRIDAY
NIGHT...DECREASING TO SLIGHT CHANCE IN THE VALLEYS FOR SATURDAY.
THERE WILL CONTINUE TO BE A SOMEWHAT BETTER CHANCE FOR A PASSING
SNOW SHOWER OVER THE HIGHER TERRAIN BOTH FRIDAY AND SATURDAY WITH
THE NORTHWEST CYCLONIC FLOW PERSISTING.
IT LOOKS LIKE DRIER WEATHER WILL FINALLY PREVAIL FOR LATE SATURDAY
INTO SUNDAY...ALTHOUGH THE DEGREE OF CLOUD COVER WILL DEPEND ON HOW
QUICKLY THE CUT-OFF LOW MOVES OUT TO SEA. THE ECMWF IS RATHER SLOW
WITH THE DEPARTURE OF THE CUT-OFF...LINGERING CYCLONIC FLOW UNTIL
SUNDAY...WHILE THE GFS HAS AN UPPER LEVEL RIDGE BUILDING IN BY LATE
SATURDAY. AGAIN...THIS WILL HAVE IMPLICATIONS ON CLOUD COVER BUT WE
ARE EXPECTING PRECIP-FREE CONDITIONS ON SUNDAY. DESPITE RISING UPPER
LEVEL HEIGHTS/TEMPS...SURFACE TEMPS ARE ONLY EXPECTED TO BE SLIGHTLY
ABOVE NORMAL DUE TO EXPECTED SHALLOW MIXING THIS TIME OF YEAR.
TRANQUIL WEATHER LOOKS TO CONTINUE INTO MONDAY...WITH HIGH PRESSURE
AT THE SURFACE AND ALOFT FIRMLY ENTRENCHED OVER THE REGION WITH GOOD
AGREEMENT BETWEEN THE ECMWF/GFS. ANOTHER SYSTEM MAY APPROACH FROM
THE WEST FOR MON NT AND TUE. WILL ADD SLIGHT CHC POPS...AS THERE IS
CONSIDERABLE UNCERTAINTY FOR EARLY NEXT WEEK WHETHER A SOUTHERN
STREAM SYSTEM PHASES WITH THE NORTHERN STREAM YET AGAIN...ALBEIT IN
A WEAKER STATE THAN THIS WEEK.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
A SIGNIFICANT DEVELOPING COASTAL STORM WITH MULTIPLE PRECIPITATION
TYPES WILL IMPACT THE AREA TODAY THROUGH WEDNESDAY.
SPOTTY FREEZING DRIZZLE WILL AFFECT THE TAF SITES UNTIL THE STEADIER
PRECIPITATION ARRIVES FROM SOUTH TO NORTH BETWEEN 12Z-15Z/TUE. ONCE
IT ARRIVES...EACH TAF SITE WILL EXPERIENCE VARYING PRECIPITATION
TYPES. MAINLY IFR/LIFR CONDITIONS ARE EXPECTED ABOUT 1-2 HOURS AFTER
THE STEADIER PRECIP BEGINS. HERE ARE SOME SPECIFICS...
KGFL...STEADY MIX OF SNOW/SLEET SHOULD DEVELOP BETWEEN 14Z-16Z/TUE.
THIS SHOULD PERSIST FOR ABOUT 2 HOURS...BEFORE TRANSITIONING TO
MAINLY A FREEZING RAIN/SLEET MIX BETWEEN 17Z-19Z/TUE. FREEZING RAIN
AND SLEET...MODERATE TO HEAVY AT TIMES...SHOULD THEN CHANGE TO PLAIN
RAIN BETWEEN 22Z/TUE-00Z/WED...AND GRADUALLY DECREASE IN INTENSITY.
OCCASIONAL LIGHT RAIN...POSSIBLY CHANGING BACK TO SLEET OR WET
SNOW...WILL LINGER THROUGH 12Z/WED.
KALB...PATCHY FREEZING DRIZZLE SHOULD TRANSFORM TO STEADIER FREEZING
RAIN AND SLEET BETWEEN 13Z-15Z/TUE. SOME WET SNOW COULD BE MIXED IN
AT TIMES...ESP AT THE ONSET. THEN...MAINLY A FREEZING RAIN AND SLEET
MIX...MODERATE TO HEAVY AT TIMES...WILL PERSIST THROUGH AROUND
19Z-21Z/TUE...BEFORE CHANGING TO PLAIN RAIN AND SOME SLEET. RAIN AND
SLEET SHOULD CHANGE TO OCCASIONAL LIGHT RAIN OR DRIZZLE BETWEEN
01Z-03Z/WED. SOME SNOW COULD MIX BACK IN AFTER 05Z/WED.
KPOU...A PERIOD OF FREEZING RAIN AND SOME SLEET WILL CHANGE TO PLAIN
RAIN BETWEEN 13Z-15Z/TUE...WITH MODERATE TO HEAVY RAIN AT TIMES
EXPECTED THROUGH MUCH OF THE AFTERNOON. RAIN SHOULD BECOME MORE
INTERMITTENT AND LIGHTER AFTER 03Z/WED.
KPSF...PATCHY FREEZING DRIZZLE SHOULD BECOME A STEADY MIX OF SLEET
AND FREEZING RAIN BETWEEN 13Z-15Z/TUE...WITH SOME WET SNOW POSSIBLY
MIXED IN AT TIMES. THIS MIX SHOULD CHANGE TO A PLAIN RAIN/SLEET MIX
BETWEEN 16Z-18Z/TUE...WHICH MAY BE MODERATE TO HVY AT TIMES.
PRECIPITATION SHOULD DECREASE IN INTENSITY BY OR AFTER
05Z/WED...WITH A MIX OF RAIN AND SLEET POSSIBLE.
WINDS WILL INITIALLY BE N-NE AROUND 5-10 KTS...INCREASING TO 10-15
KTS WITH GUST NEAR OR EXCEEDING 20-25 KTS BY THIS AFTERNOON AND INTO
TONIGHT.
OUTLOOK...
WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SN.
THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A FLOOD WATCH REMAINS IN EFFECT FOR LITCHFIELD COUNTY
CONNECTICUT...DUTCHESS COUNTY NEW YORK AND EASTERN ULSTER COUNTY
NEW YORK...FOR THIS MORNING THROUGH TONIGHT.
A COASTAL STORM WILL BRING WIDESPREAD PRECIPITATION TO THE AREA
FOR TODAY INTO TONIGHT. FOR NORTHWESTERN AND HIGH TERRAIN
AREAS...THIS PRECIPITATION WILL FALL PRIMARY AS SNOW OR A WINTRY
MIX. MEANWHILE...ACROSS SOUTHERN AND VALLEY AREAS...PRECIP WILL
BEGIN AS A PERIOD OF SNOW OR A WINTRY MIX AND TRANSITION TO RAIN.
TOTAL LIQUID EQUIVALENT VALUES WILL BE 0.50 OVER THE WESTERN
ADIRONDACKS TO NEARLY 2.00 INCHES OVER WESTERN NEW ENGLAND. WITH
MUCH OF THIS FALLING AS RAINFALL OVER LITCHFIELD COUNTY AND THE
MID HUDSON VALLEY...THERE WILL BE A LOT OF RUNOFF...ESPECIALLY
DURING LATE THIS MORNING THROUGH EARLY THIS EVENING WHEN PRECIP
WILL BE HEAVIEST. THIS RAINFALL MAY LEAD TO MINOR FLOODING OF POOR
DRAINAGE AND LOW LYING AREAS...ESPECIALLY IN AREAS WHERE THE
GROUND IS FROZEN. RISES ON RIVERS AND STREAMS ARE LIKELY...AND
MINOR FLOODING CANNOT BE RULED OUT ON THE HOUSATONIC RIVER AND
IT/S TRIBUTARIES IN NW CT.
IN ADDITION...THE STRONG COASTAL LOW IS ALLOWING FOR SOME TIDAL
FLOODING ALONG COASTAL AREAS...AND THIS COULD CAUSE A BACKUP OF
WATER ON THE HUDSON RIVER. THIS COULD LEAD TO MINOR FLOODING
DURING TIMES OF HIGH TIDE IN THE POUGHKEEPSIE AREA THIS AFTERNOON.
SOME ADDITIONAL PRECIPITATION...MAINLY IN THE FORM OF SNOW...IS
POSSIBLE FOR WEDNESDAY INTO THURSDAY...BUT AMOUNTS ARE EXPECTED TO
BE LIGHT IN AREAS THAT SEE THE HEAVIEST LIQUID PRECIP TODAY. THIS
SHOULD ALLOW WATER LEVELS TO RECEDE SLOWLY OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ001-013.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ001-013.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ032-033-
038>040-042-043-047-048-051-058-063-082.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ041-
049-050-052>054-059>061-083-084.
FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ064>066.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ064>066.
MA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-
025.
VT...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/WASULA
SHORT TERM...BGM
LONG TERM...KL/JPV
AVIATION...KL/JPV
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
953 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SIGNIFICANT COASTAL STORM WILL IMPACT THE REGION TODAY WITH
WINTRY PRECIPITATION AND HEAVY RAIN...ALONG WITH STRONG TO
DAMAGING WINDS. LEFTOVER LIGHT SNOW AND RAIN SHOWERS WILL PERSIST
WEDNESDAY AND THURSDAY. SLOW IMPROVEMENT IS EXPECTED FRI INTO THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
720 AM UPDATE...
TWEAKED TEMPERATURES AND PRECIPITATION TIMING THIS MORNING.
TEMPERATURES WILL BE CRUCIAL TO DETERMINING HOW MUCH ICING OCCURS
THIS MORNING. ISSUED A SPECIAL WEATHER STATEMENT EARLIER TO
ADDRESS THIS DURING THE MORNING COMMUTE. BEYOND THAT...FORECAST
REMAINS LARGELY ON TRACK.
PREVIOUS DISCUSSION...
* HIGHLIGHTS...
- WINTRY PRECIPITATION TYPES ERODING WITH TIME TO THE N/W
- SNOW / ICE ACCUMULATIONS REMAIN AT WINTER-WX-ADVISORY LEVELS
- HEAVY RAIN OF 2-3 INCHES LENDING TO POSSIBLE FLOODING
- STRONG TO DAMAGING E-WINDS YIELDING WIND ADV HEADLINES
* SYNOPTICALLY...
PRESENT OFFSHORE LOW OFF THE MID-ATLANTIC CONUS BECOMES USURPED BY
AN AMPLIFYING TROUGH DIGGING THROUGH THE E-CONUS. ACROSS A REGION OF
FAVORABLE BAROCLINICITY / ATTENDANT DYNAMICS / STRONG FORCING AND
DEEP-LAYER ASCENT YIELDS A RAPIDLY DEEPENING AREA OF LOW PRESSURE
OFF THE DELMARVA PENINSULA THIS MORNING LIFTING N INTO S NEW ENGLAND
BY EVENING. THE LOW BECOMES STALLED AND CUTOFF FROM THE MEAN FLOW UP
AGAINST HIGH PRESSURE ON NEARLY ALL SIDES AS WE GO INTO THE WEEK.
* HEAVY RAIN AND FLOODING...
INTERROGATING DEEPER...AS THE LOW DEEPENS...EXPECT DECENT LOW-LEVEL
TROWALING OF THE WARM-CONVEYER-BELT BENEATH THE RRQ/LFQ OF
ATTENDANT UPPER-LEVEL JET AXES. COMBINATION OF THE CONVERGENT
LEADING NOSE OF ISENTROPIC UPSLOPE LENDING TO THE TIGHTENING OF
THE THERMAL GRADIENT AGAINST NEIGHBORING HIGH PRESSURE YIELDING
STRONG FRONTOGENETICAL FORCING IN A REGION OF MINOR -EPV
INSTABILITY BENEATH AFOREMENTIONED DEEP-LAYER ASCENT LIKELY TO
RESULT IN A ROUGHLY W-E BANDING SETUP OF HIGHER WSR-88D RETURNS
WITHIN A WIDESPREAD COMMA-SHAPED PRECIP FIELD ALONG THE
N-PERIPHERY OF THE H85 LOW WITH THE FRONT-END THUMP OF PRECIP
ANTICIPATED AROUND MIDDAY AND PERSISTING INTO EARLY EVENING.
WHEW...DEEP BREATH. FEEL THE HRRR SIMULATED RADAR TRENDS ARE
SHOWING THIS QUITE WELL.
WILL EXPAND THE FLOOD WATCH TO INCLUDE CAPE COD AND NANTUCKET.
WITH HEIGHT OF THE E/NE-WINDS AND HEAVY RAIN CONCURRENT WITH TIMING
OF HIGH TIDE CENTERED AROUND 1 PM BELIEVE SURGE ALONG WITH BUILDING
WAVE HEIGHTS /SEE THE MARINE DISCUSSION BELOW FOR MORE DETAILS/ WILL
RESULT IN POOR-DRAINAGE ISSUES FOR COASTAL COMMUNITIES. ANTICIPATE
DRAINS TO BACK-UP BECOMING OVER-TOPPED RESULTING IN SUSCEPTIBLE LOW-
LYING AND POOR-DRAINAGE AREAS TO BECOME FLOODED.
AM ALSO CONCERNED FOR EVEN THOSE COMMUNITIES WITHIN THE COASTAL
PLAIN IN VICINITY OF RIVERS THAT ARE INFLUENCED BY THE TIDE /I.E.
TAUNTON RIVER...LOWER CONNECTICUT/. COULD ALSO SEE SOME EXACERBATED
FLOOD ISSUES FOR THESE AREAS.
OTHERWISE REMAINDER OF THE FLOOD WATCH REMAINS IN PLACE. PWATS OF
1.25-INCHES FORECAST /ROUGHLY +2 STANDARD DEVIATIONS ABOVE-NORMAL/
AND FORECAST RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS ANTICIPATED. GROUND IS PRETTY SOLID /IMPERVIOUS/ THUS EXPECT
MOST OF THE RAINFALL TO BECOME RUNOFF. MAJORITY OF MAINSTEM RIVERS
OVER THE INTERIOR SHOULD BE ABLE TO HANDLE THE RAIN...SO CONCERNS
LIE IN THE REALM OF URBAN / POOR DRAINAGE FLOODING...ESPECIALLY IF
DRAINS ARE STILL LEAF-CLOGGED. BIGGEST AREA OF CONCERN IS WITHIN THE
METRO-AREA CORRIDORS...ESPECIALLY BOSTON-PROVIDENCE. MAY NEED TO
EXPAND THE WATCH ACROSS N-CENTRAL AND NW MA PENDING THE TIMING AT
WHICH WINTRY-PRECIP TYPES TRANSITION TO RAIN.
* WINTRY PRECIPITATION...
OUTCOMES DEPENDENT ON THERMAL FIELDS ALOFT...WHERE AROUND H925-H85
BY MORNING CONDITIONS ARE WARMING CONSIDERABLY UP AGAINST COLDER AIR
AND HIGH PRESSURE SITUATED N/W. A SW-NE FREEZING LINE AROUND NW-CT
INTO S NH INITIALLY MODIFIES NW AS THE LOW DEEPENS RESULTING IN THE
INCREASE OF THE SE WARM-MOIST-CONVEYER-BELT. EXPECT THICKNESSES
TO GRADUALLY RISE DURING THE HEIGHT OF THE EVENT INTO EVENING.
AT THE SURFACE...AREAS BELOW FREEZING ERODE WITH INCREASING ONSHORE
E/NE-WINDS DURING THE MORNING /MORE ON THAT LATER/. UNCERTAINTY
CONTINUES WITH 09.0Z HIGH-RES MODELS DIFFERING IN TIMING OF EROSION.
AS MENTIONED IN PRIOR DISCUSSIONS...FOR AREAS THAT ARE WITHIN OR
ON THE CUSP OF BELOW-FREEZING TEMPERATURES BY 1-2C...LINGERING AN
HOUR OR TWO MORE OR LESS CAN MAKE ALL THE DIFFERENCE WITH REGARDS
TO WINTER-WEATHER HEAD-LINES. H975-925 AGEOSTROPHIC FLOW IS
NOTABLY PERSISTENT AND STRONG OUT OF THE W AS THE LOW INTENSIFIES
TOWARDS S NEW ENGLAND. BUT NOT MUCH OF A N-COMPONENT NOR FROM
ARCTIC-SOURCE REGIONS...SO BELIEVE THIS WILL DO LITTLE TO MAINTAIN
/ PERSIST COLD AIR OVER THE REGION AGAINST STRONG ONSHORE E-FLOW.
WILL GO CLOSE TO THE NEAR-TERM HIGH-RES GUIDANCE WHILE INCORPORATING
THE WRF-NMM WITH REGARDS TO THERMAL FIELDS...WHICH ARE HANDLING THE
SURFACE TEMPERATURES DECENTLY. PREFERENCE TO THE 09.0Z ECMWF IS ALSO
GIVEN ESPECIALLY WHEN EVALUATING H100-H85 THICKNESSES. ONLY WRF-ARW
AND RAP LEAN ON THE WARM SIDE OF THE GUIDANCE OVER ALL OTHERS.
ALSO WILL GO WITH A TOP-DOWN APPROACH TOWARDS PRECIPITATION-TYPE
THAT INCORPORATES THE INCREASING MOISTURE FROM THE S WITHIN OR
ABOVE THE DENDRITIC GROWTH ZONE REGION.
SO OVERALL...EXPECTING THE GRADUAL EROSION OF THE COASTAL-FRONT WITH
INCREASING ONSHORE E-FLOW. PUSH OF WARMER AIR ALOFT AHEAD OF THE
DEEPENING LOW WILL RESULT IN PRECIP-TYPE TRANSITION FAIRLY QUICKLY
TO A SLEET / FREEZING RAIN MIX. THIS HAS SUBSEQUENTLY BUMPED DOWN
SNOWFALL AMOUNTS RESULTING IN A RANGE OF 2-4 INCHES ACROSS NW MA.
MOST OF THE REGION CHANGES OVER TO RAIN BY LATE MORNING INTO MIDDAY
WITH ONLY THE HIGHER ELEVATIONS OF THE BERKSHIRES CONTINUALLY UNDER
THE THREAT OF FREEZING RAIN.
HAVE DROPPED WINTER-STORM WATCHES AND REPLACED WITH WINTER WEATHER
ADVISORIES. HAVE TRIMMED THE EASTERN-EXTENT WITH EROSION OF THE
COASTAL FRONT AND THE SURGE OF WARMER AIR ONSHORE. AGAIN...THE
THERMAL FIELDS DISCUSSION ABOVE GIVE AN INDICATION OF PREFERRED
MODEL GUIDANCE. SHOULD SEE WINTER WEATHER HEADLINES DROP MAINLY
AROUND THE MIDDAY HOURS.
MID-LEVEL DRY-SLOT WRAPPING INTO A DEVELOPING OCCLUSION BEGINNING
TUESDAY EVENING SHOULD RESULT IN A LULL OF PRECIPITATION AS WE GO
INTO WEDNESDAY MORNING.
* STRONG TO DAMAGING WINDS...
NOTING E-WINDS 1-2 KFT AGL WILL BE AROUND 55 MPH AROUND THE MIDDAY
INTO AFTERNOON HOURS...THE PRESENCE OF WARMER AIR ALOFT LENDING TO
AN INVERSION JUST ABOVE THE SURFACE MAKES IT DIFFICULT TO CONSIDER A
HIGH WIND WARNING. THIS DESPITE WARMER AIR WIGGLING ITS WAY UP FROM
THE S AT THE SURFACE...AND A WARMER OCEAN /THOUGH NOW AROUND THE LOW-
50S/. BOUNDARY-LAYER MIXING WILL BE LIMITED. HIGH-END WIND ADVISORY
CRITERIA IS EXPECTED...BUT DO NOT EXPECT WIDESPREAD GUSTS EXCEEDING
HIGH WIND WARNING CRITERIA. THUS WENT WITH THE WIND ADVISORY.
COULD PRECIPITATION-DRAG PROCESSES BRING FASTER MOMENTUM TO THE
SURFACE? YES...IT IS QUITE POSSIBLE...EVEN IF THUNDERSTORMS ARE IN
THE MIX WHICH IS IN THE FORECAST FOR THE FAR SE-WATERS ADJACENT TO
THE CAPE AND ISLANDS. HAVE GONE WITH THE HEADLINES THAT CONVEY THE
HIGHEST CONFIDENCE.
* COASTAL FLOODING...
SEE TIDES/COASTAL FLOODING SECTION BELOW FOR DETAILS.
&&
.SHORT TERM /WEDNESDAY/...
SEE LONG TERM SECTION BELOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* LINGERING RAIN/SNOW SHOWERS INTO THU AS CLOSED LOW SLOWLY EXITS
* IMPROVING CONDITIONS FRI INTO THIS WEEKEND
DECENT MODEL AGREEMENT BOTH AT THE SURFACE AND ALOFT WEDNESDAY
INTO FRIDAY. MORE SIGNIFICANT DIFFERENCES ARISE FRIDAY NIGHT INTO
EARLY NEXT WEEK. AS SUCH...FAVORED A CONSENSUS BLEND TO UPDATE
THIS PORTION OF THE FORECAST. THIS WAS TO SMOOTH OVER THE MINOR
DIFFERENCES INTO FRIDAY...AS WELL AS MINIMIZE ERROR AFTER THAT
POINT.
CLOSED LOW WILL BE SLOW TO EXIT NEW ENGLAND...AND 09/00Z GUIDANCE
MODELS CONTINUE TO SHOW A DEEP UPPER LOW OVER NORTHERN NEW ENGLAND
FINALLY MOVING OUT TO SEA SATURDAY NIGHT. ONE OF THE PRIMARY
ISSUES WITH THIS FORECAST WILL BE THE AMOUNT OF MOISTURE
AVAILABLE. THINKING THERE WILL BE ENOUGH TO KEEP SKIES MOSTLY
CLOUD INTO FRIDAY NIGHT. HOW MUCH WILL BE LEFTOVER TO US IN
GENERATING PRECIPITATION IS ANOTHER MATTER. CONTINUED THE PREVIOUS
FORECAST OF A GRADUAL DRYING OUT PROCESS FRIDAY INTO SATURDAY.
HIGH PRESSURE SHOULD BE IN CONTROL OF OUR WEATHER SUNDAY INTO
MONDAY.
NEAR OR SLIGHTLY BELOW NORMAL TEMPERATURES EXPECTED THROUGH THIS
PERIOD.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH WEDNESDAY MORNING/...
12Z UPDATE...
TODAY INTO TONIGHT...MODERATE CONFIDENCE.
MIX OF MVFR-IFR CIGS / VSBYS WITH MAINLY +RA. AN ISOLATED TSRA IS
POSSIBLE FOR FAR SE-COASTAL TERMINALS. OTHERWISE GRADUAL EROSION
TO N/W OF FZRA/PL/SN INTO THE EARLY-AFTERNOON HOURS DURING WHICH
TIME WINDS WILL INCREASE OUT OF THE E WITH STRONGEST GUSTS ALONG
THE E-SHORELINE MAINLY AROUND 40 KT WITH LOCALLY HIGHER GUSTS UP
TO 50 KT. WILL ALSO SEE AN ACCOMPANYING LLWS THREAT WITH WINDS
AROUND 2 KFT AGL OUT OF THE E AROUND 60 KTS.
KBOS TERMINAL...MODERATE CONFIDENCE.
FEEL CONFIDENT WITH TRENDS BUT NOT SO MUCH WITH SPECIFICS. HIGH
CONFIDENCE OF CONTINUED +RA WITH INCREASING E-WINDS. GUSTS UP TO
40 KT ANTICIPATED TOWARDS THE MIDDAY HRS. WIND ADVISORY LENDING
TO ISSUANCE OF AIRPORT WEATHER WARNING.
KBDL TERMINAL...MODERATE CONFIDENCE.
FZRA PERSISTING INTO THE EARLY-MORNING HOURS...THEN CHANGING OVER
TO RAIN. NOT ABSOLUTELY CERTAIN ON TIMING BUT CONFIDENT WITH
TRENDS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE. MVFR/IFR IN
SCATTERED RAIN OR SNOW SHOWERS.
FRIDAY...MODERATE CONFIDENCE. MVFR IN ISOLATED RAIN/SNOW SHOWERS.
SATURDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
5 AM UPDATE...
BASED ON FORECAST CONFIDENCE...HAVE GONE WITH STORM WARNINGS FOR
THE OUTER WATERS WITH THE EXPECTATION OF GUSTS AROUND 45-50 KT.
BUT GREATER CONFIDENCE OF THE INNER-WATERS REACHING HIGH-END GALE
WARNING CRITERIA PERMITTED THE DISCONTINUING OF THE STORM WATCH.
CAN NOT RULE OUT AN ISOLATED GUST UP TO 50 KTS OVER THE INNER-
WATERS...BUT WITH IT NOT ANTICIPATED TO BE WIDESPREAD...KEPT WITH
GALE WARNINGS. STRONGEST E-WINDS OCCURRING TOWARDS THE MIDDAY AND
CONTINUING INTO THE EARLY EVENING HOURS.
SEAS BUILDING 15 TO 20 FEET WITH INCREASING E-WINDS AHEAD OF A
DEEPENING AREA OF LOW PRESSURE OF THE DELMARVA PENINSULA PRESENTLY
AS IT LIFTS N INTO S NEW ENGLAND TOWARDS THIS EVENING. EXPECT
ACCOMPANYING HEAVY RAIN WHICH WILL YIELD VISIBILITY RESTRICTIONS
ON THE WATERS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
SMALL CRAFT ADVISORIES WILL LIKELY NEED TO CONTINUE THROUGH
THURSDAY NIGHT ACROSS THE OCEAN-EXPOSED COASTAL WATERS...MAINLY
DUE TO ROUGH SEAS. THERE COULD ALSO BE SOME WEST/SOUTHWEST GUSTS
UP TO 25 KT AS WELL. ALSO SHOULD SEE LEFTOVER SCATTERED RAIN/SNOW
SHOWERS.
FRIDAY INTO SATURDAY...MODERATE CONFIDENCE.
SLOW IMPROVEMENT CONTINUES WITH DIMINISHING WINDS AND SEAS. SEAS
SHOULD FINALLY DROP BELOW 5 FT ACROSS ALL BUT THE OUTERMOST
COASTAL WATERS FRI EVENING...THEN REMAIN BELOW SMALL CRAFT
ADVISORY THRESHOLDS ACROSS ALL WATERS SATURDAY.
&&
.HYDROLOGY...
UPDATED 950 AM TUE...
EXPANDED FLOOD WATCH TO INCLUDE MARTHAS VINEYARD AND BLOCK ISLAND.
ALTHOUGH RAINFALL TOTALS WILL BE 1.5 TO 2.5 INCHES...COMBINATION
OF RAINFALL AND RISING TIDE THROUGH EARLY AFTERNOON MAY LEAD TO
SIGNIFICANT FLOODING ESPECIALLY ON E/SE SHORELINES. BUOYS
REPORTING 5-6 FT SEAS ON NANTUCKET SOUND AND 11 FT SE OF BLOCK
ISLAND. SIMILAR SITUATION FOR CAPE COD AND NANTUCKET.
MAIN CONCERN CONTINUES TO BE POTENTIAL FOR SIGNIFICANT URBAN
FLOODING...ESPECIALLY IN RI AND E MA. ALREADY SEEING RAINFALL
RATES OF NEARLY 2 INCHES PER HOUR ACROSS SOUTHERN CT /KSNC ASOS/
WHICH WILL TRANSLATE OVER OUR AREA BY EARLY AFTERNOON. SOME OF THE
URBAN HOT SPOTS SUCH AS PEABODY...FALL RIVER...NEW BEDFORD AND
CRANSTON MAY BE ESPECIALLY VULNERABLE TO FLOODING. TOTALS OF 2 TO
3 INCHES ARE EXPECTED WITH A FEW 3 OR 4 INCH TOTALS NOT OUT OF
QUESTION NEAR I-95 CORRIDOR.
FLOODING OF SMALL STREAMS IS ALSO A POSSIBILITY...BUT WORST CASE
WOULD BE FOR MINOR FLOODING IF TOTALS EXCEED 3 INCHES.
NOT EXPECTING FLOODING OF LARGER RIVERS. LATEST NERFC GUIDANCE
BRINGS LOWER CT RIVER AT MIDDLE HADDAM TO ACTION STAGE...WHICH IS
PRIMARILY BASED ON SURGE OF 2 FT INTO LOWER CT RIVER. WE MAY ALSO
SEE SIMILAR SURGE ALONG PAWCATUCK RIVER NEAR WESTERLY RI WHICH
COULD BRING RISES SLIGHTLY HIGHER THAN CURRENTLY FORECAST.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY CONTINUES FOR EASTERN MA. COMBINATION OF
WINDS / SEAS / SURGE OF AROUND 1.5 TO 2 FEET DURING THE MIDDAY
HIGH-TIDE YIELDS THE LIKELIHOOD OF OBSERVING MINOR COASTAL
FLOODING AND BEACH EROSION FOR E-FACING SHORELINES WHERE SEAS OF
12 TO 15 FEET ARE POSSIBLE.
AS NOTED IN THE HYDROLOGY PORTION ABOVE...LOCAL STREAMS AND
TRIBUTARIES EMPTYING INTO THE SEA COULD SEE BACK-FILLING ISSUES AS
THE HEAVY RAIN IS ANTICIPATED DURING THE TIME OF HIGH-TIDE. COULD
SEE FLOODING ISSUES EXACERBATED FOR EASTERN MA SHORELINE
COMMUNITIES.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ002>004.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ002>004.
MA...FLOOD WATCH THROUGH LATE TONIGHT FOR MAZ005>007-011>024.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR MAZ007-014>016-
019>024.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ007-015-016-019-022-024.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MAZ005-006-011-012.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ003-004-009-010-026.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
MAZ002-008.
RI...FLOOD WATCH THROUGH LATE TONIGHT FOR RIZ001>008.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR RIZ006>008.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ231>234-251.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ230.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ235>237.
STORM WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...BELK/SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
HYDROLOGY...JWD
TIDES/COASTAL FLOODING...STAFF
AREA FORECAST DISCUSSION
NWS TAUNTON MA
721 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SIGNIFICANT COASTAL STORM WILL IMPACT THE REGION TODAY WITH
WINTRY PRECIPITATION AND HEAVY RAIN...ALONG WITH STRONG TO
DAMAGING WINDS. LEFTOVER LIGHT SNOW AND RAIN SHOWERS WILL PERSIST
WEDNESDAY AND THURSDAY. SLOW IMPROVEMENT IS EXPECTED FRI INTO THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
720 AM UPDATE...
TWEAKED TEMPERATURES AND PRECIPITATION TIMING THIS MORNING.
TEMPERATURES WILL BE CRUCIAL TO DETERMINING HOW MUCH ICING OCCURS
THIS MORNING. ISSUED A SPECIAL WEATHER STATEMENT EARLIER TO
ADDRESS THIS DURING THE MORNING COMMUTE. BEYOND THAT...FORECAST
REMAINS LARGELY ON TRACK.
PREVIOUS DISCUSSION...
* HIGHLIGHTS...
- WINTRY PRECIPITATION TYPES ERODING WITH TIME TO THE N/W
- SNOW / ICE ACCUMULATIONS REMAIN AT WINTER-WX-ADVISORY LEVELS
- HEAVY RAIN OF 2-3 INCHES LENDING TO POSSIBLE FLOODING
- STRONG TO DAMAGING E-WINDS YIELDING WIND ADV HEADLINES
* SYNOPTICALLY...
PRESENT OFFSHORE LOW OFF THE MID-ATLANTIC CONUS BECOMES USURPED BY
AN AMPLIFYING TROUGH DIGGING THROUGH THE E-CONUS. ACROSS A REGION OF
FAVORABLE BAROCLINICITY / ATTENDANT DYNAMICS / STRONG FORCING AND
DEEP-LAYER ASCENT YIELDS A RAPIDLY DEEPENING AREA OF LOW PRESSURE
OFF THE DELMARVA PENINSULA THIS MORNING LIFTING N INTO S NEW ENGLAND
BY EVENING. THE LOW BECOMES STALLED AND CUTOFF FROM THE MEAN FLOW UP
AGAINST HIGH PRESSURE ON NEARLY ALL SIDES AS WE GO INTO THE WEEK.
* HEAVY RAIN AND FLOODING...
INTERROGATING DEEPER...AS THE LOW DEEPENS...EXPECT DECENT LOW-LEVEL
TROWALING OF THE WARM-CONVEYER-BELT BENEATH THE RRQ/LFQ OF
ATTENDANT UPPER-LEVEL JET AXES. COMBINATION OF THE CONVERGENT
LEADING NOSE OF ISENTROPIC UPSLOPE LENDING TO THE TIGHTENING OF
THE THERMAL GRADIENT AGAINST NEIGHBORING HIGH PRESSURE YIELDING
STRONG FRONTOGENETICAL FORCING IN A REGION OF MINOR -EPV
INSTABILITY BENEATH AFOREMENTIONED DEEP-LAYER ASCENT LIKELY TO
RESULT IN A ROUGHLY W-E BANDING SETUP OF HIGHER WSR-88D RETURNS
WITHIN A WIDESPREAD COMMA-SHAPED PRECIP FIELD ALONG THE
N-PERIPHERY OF THE H85 LOW WITH THE FRONT-END THUMP OF PRECIP
ANTICIPATED AROUND MIDDAY AND PERSISTING INTO EARLY EVENING.
WHEW...DEEP BREATH. FEEL THE HRRR SIMULATED RADAR TRENDS ARE
SHOWING THIS QUITE WELL.
WILL EXPAND THE FLOOD WATCH TO INCLUDE CAPE COD AND NANTUCKET.
WITH HEIGHT OF THE E/NE-WINDS AND HEAVY RAIN CONCURRENT WITH TIMING
OF HIGH TIDE CENTERED AROUND 1 PM BELIEVE SURGE ALONG WITH BUILDING
WAVE HEIGHTS /SEE THE MARINE DISCUSSION BELOW FOR MORE DETAILS/ WILL
RESULT IN POOR-DRAINAGE ISSUES FOR COASTAL COMMUNITIES. ANTICIPATE
DRAINS TO BACK-UP BECOMING OVER-TOPPED RESULTING IN SUSCEPTIBLE LOW-
LYING AND POOR-DRAINAGE AREAS TO BECOME FLOODED.
AM ALSO CONCERNED FOR EVEN THOSE COMMUNITIES WITHIN THE COASTAL
PLAIN IN VICINITY OF RIVERS THAT ARE INFLUENCED BY THE TIDE /I.E.
TAUNTON RIVER...LOWER CONNECTICUT/. COULD ALSO SEE SOME EXACERBATED
FLOOD ISSUES FOR THESE AREAS.
OTHERWISE REMAINDER OF THE FLOOD WATCH REMAINS IN PLACE. PWATS OF
1.25-INCHES FORECAST /ROUGHLY +2 STANDARD DEVIATIONS ABOVE-NORMAL/
AND FORECAST RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS ANTICIPATED. GROUND IS PRETTY SOLID /IMPERVIOUS/ THUS EXPECT
MOST OF THE RAINFALL TO BECOME RUNOFF. MAJORITY OF MAINSTEM RIVERS
OVER THE INTERIOR SHOULD BE ABLE TO HANDLE THE RAIN...SO CONCERNS
LIE IN THE REALM OF URBAN / POOR DRAINAGE FLOODING...ESPECIALLY IF
DRAINS ARE STILL LEAF-CLOGGED. BIGGEST AREA OF CONCERN IS WITHIN THE
METRO-AREA CORRIDORS...ESPECIALLY BOSTON-PROVIDENCE. MAY NEED TO
EXPAND THE WATCH ACROSS N-CENTRAL AND NW MA PENDING THE TIMING AT
WHICH WINTRY-PRECIP TYPES TRANSITION TO RAIN.
* WINTRY PRECIPITATION...
OUTCOMES DEPENDENT ON THERMAL FIELDS ALOFT...WHERE AROUND H925-H85
BY MORNING CONDITIONS ARE WARMING CONSIDERABLY UP AGAINST COLDER AIR
AND HIGH PRESSURE SITUATED N/W. A SW-NE FREEZING LINE AROUND NW-CT
INTO S NH INITIALLY MODIFIES NW AS THE LOW DEEPENS RESULTING IN THE
INCREASE OF THE SE WARM-MOIST-CONVEYER-BELT. EXPECT THICKNESSES
TO GRADUALLY RISE DURING THE HEIGHT OF THE EVENT INTO EVENING.
AT THE SURFACE...AREAS BELOW FREEZING ERODE WITH INCREASING ONSHORE
E/NE-WINDS DURING THE MORNING /MORE ON THAT LATER/. UNCERTAINTY
CONTINUES WITH 09.0Z HIGH-RES MODELS DIFFERING IN TIMING OF EROSION.
AS MENTIONED IN PRIOR DISCUSSIONS...FOR AREAS THAT ARE WITHIN OR
ON THE CUSP OF BELOW-FREEZING TEMPERATURES BY 1-2C...LINGERING AN
HOUR OR TWO MORE OR LESS CAN MAKE ALL THE DIFFERENCE WITH REGARDS
TO WINTER-WEATHER HEAD-LINES. H975-925 AGEOSTROPHIC FLOW IS
NOTABLY PERSISTENT AND STRONG OUT OF THE W AS THE LOW INTENSIFIES
TOWARDS S NEW ENGLAND. BUT NOT MUCH OF A N-COMPONENT NOR FROM
ARCTIC-SOURCE REGIONS...SO BELIEVE THIS WILL DO LITTLE TO MAINTAIN
/ PERSIST COLD AIR OVER THE REGION AGAINST STRONG ONSHORE E-FLOW.
WILL GO CLOSE TO THE NEAR-TERM HIGH-RES GUIDANCE WHILE INCORPORATING
THE WRF-NMM WITH REGARDS TO THERMAL FIELDS...WHICH ARE HANDLING THE
SURFACE TEMPERATURES DECENTLY. PREFERENCE TO THE 09.0Z ECMWF IS ALSO
GIVEN ESPECIALLY WHEN EVALUATING H100-H85 THICKNESSES. ONLY WRF-ARW
AND RAP LEAN ON THE WARM SIDE OF THE GUIDANCE OVER ALL OTHERS.
ALSO WILL GO WITH A TOP-DOWN APPROACH TOWARDS PRECIPITATION-TYPE
THAT INCORPORATES THE INCREASING MOISTURE FROM THE S WITHIN OR
ABOVE THE DENDRITIC GROWTH ZONE REGION.
SO OVERALL...EXPECTING THE GRADUAL EROSION OF THE COASTAL-FRONT WITH
INCREASING ONSHORE E-FLOW. PUSH OF WARMER AIR ALOFT AHEAD OF THE
DEEPENING LOW WILL RESULT IN PRECIP-TYPE TRANSITION FAIRLY QUICKLY
TO A SLEET / FREEZING RAIN MIX. THIS HAS SUBSEQUENTLY BUMPED DOWN
SNOWFALL AMOUNTS RESULTING IN A RANGE OF 2-4 INCHES ACROSS NW MA.
MOST OF THE REGION CHANGES OVER TO RAIN BY LATE MORNING INTO MIDDAY
WITH ONLY THE HIGHER ELEVATIONS OF THE BERKSHIRES CONTINUALLY UNDER
THE THREAT OF FREEZING RAIN.
HAVE DROPPED WINTER-STORM WATCHES AND REPLACED WITH WINTER WEATHER
ADVISORIES. HAVE TRIMMED THE EASTERN-EXTENT WITH EROSION OF THE
COASTAL FRONT AND THE SURGE OF WARMER AIR ONSHORE. AGAIN...THE
THERMAL FIELDS DISCUSSION ABOVE GIVE AN INDICATION OF PREFERRED
MODEL GUIDANCE. SHOULD SEE WINTER WEATHER HEADLINES DROP MAINLY
AROUND THE MIDDAY HOURS.
MID-LEVEL DRY-SLOT WRAPPING INTO A DEVELOPING OCCLUSION BEGINNING
TUESDAY EVENING SHOULD RESULT IN A LULL OF PRECIPITATION AS WE GO
INTO WEDNESDAY MORNING.
* STRONG TO DAMAGING WINDS...
NOTING E-WINDS 1-2 KFT AGL WILL BE AROUND 55 MPH AROUND THE MIDDAY
INTO AFTERNOON HOURS...THE PRESENCE OF WARMER AIR ALOFT LENDING TO
AN INVERSION JUST ABOVE THE SURFACE MAKES IT DIFFICULT TO CONSIDER A
HIGH WIND WARNING. THIS DESPITE WARMER AIR WIGGLING ITS WAY UP FROM
THE S AT THE SURFACE...AND A WARMER OCEAN /THOUGH NOW AROUND THE LOW-
50S/. BOUNDARY-LAYER MIXING WILL BE LIMITED. HIGH-END WIND ADVISORY
CRITERIA IS EXPECTED...BUT DO NOT EXPECT WIDESPREAD GUSTS EXCEEDING
HIGH WIND WARNING CRITERIA. THUS WENT WITH THE WIND ADVISORY.
COULD PRECIPITATION-DRAG PROCESSES BRING FASTER MOMENTUM TO THE
SURFACE? YES...IT IS QUITE POSSIBLE...EVEN IF THUNDERSTORMS ARE IN
THE MIX WHICH IS IN THE FORECAST FOR THE FAR SE-WATERS ADJACENT TO
THE CAPE AND ISLANDS. HAVE GONE WITH THE HEADLINES THAT CONVEY THE
HIGHEST CONFIDENCE.
* COASTAL FLOODING...
SEE TIDES/COASTAL FLOODING SECTION BELOW FOR DETAILS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGHLIGHTS...
* LINGERING RAIN/SNOW SHOWERS INTO THU AS CLOSED LOW SLOWLY EXITS
* IMPROVING CONDITIONS FRI INTO THIS WEEKEND
DECENT MODEL AGREEMENT BOTH AT THE SURFACE AND ALOFT WEDNESDAY
INTO FRIDAY. MORE SIGNIFICANT DIFFERENCES ARISE FRIDAY NIGHT INTO
EARLY NEXT WEEK. AS SUCH...FAVORED A CONSENSUS BLEND TO UPDATE
THIS PORTION OF THE FORECAST. THIS WAS TO SMOOTH OVER THE MINOR
DIFFERENCES INTO FRIDAY...AS WELL AS MINIMIZE ERROR AFTER THAT
POINT.
CLOSED LOW WILL BE SLOW TO EXIT NEW ENGLAND...AND 09/00Z GUIDANCE
MODELS CONTINUE TO SHOW A DEEP UPPER LOW OVER NORTHERN NEW ENGLAND
FINALLY MOVING OUT TO SEA SATURDAY NIGHT. ONE OF THE PRIMARY
ISSUES WITH THIS FORECAST WILL BE THE AMOUNT OF MOISTURE
AVAILABLE. THINKING THERE WILL BE ENOUGH TO KEEP SKIES MOSTLY
CLOUD INTO FRIDAY NIGHT. HOW MUCH WILL BE LEFTOVER TO US IN
GENERATING PRECIPITATION IS ANOTHER MATTER. CONTINUED THE PREVIOUS
FORECAST OF A GRADUAL DRYING OUT PROCESS FRIDAY INTO SATURDAY.
HIGH PRESSURE SHOULD BE IN CONTROL OF OUR WEATHER SUNDAY INTO
MONDAY.
NEAR OR SLIGHTLY BELOW NORMAL TEMPERATURES EXPECTED THROUGH THIS
PERIOD.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH WEDNESDAY MORNING/...
12Z UPDATE...
TODAY INTO TONIGHT...MODERATE CONFIDENCE.
MIX OF MVFR-IFR CIGS / VSBYS WITH MAINLY +RA. AN ISOLATED TSRA IS
POSSIBLE FOR FAR SE-COASTAL TERMINALS. OTHERWISE GRADUAL EROSION
TO N/W OF FZRA/PL/SN INTO THE EARLY-AFTERNOON HOURS DURING WHICH
TIME WINDS WILL INCREASE OUT OF THE E WITH STRONGEST GUSTS ALONG
THE E-SHORELINE MAINLY AROUND 40 KT WITH LOCALLY HIGHER GUSTS UP
TO 50 KT. WILL ALSO SEE AN ACCOMPANYING LLWS THREAT WITH WINDS
AROUND 2 KFT AGL OUT OF THE E AROUND 60 KTS.
KBOS TERMINAL...MODERATE CONFIDENCE.
FEEL CONFIDENT WITH TRENDS BUT NOT SO MUCH WITH SPECIFICS. HIGH
CONFIDENCE OF CONTINUED +RA WITH INCREASING E-WINDS. GUSTS UP TO
40 KT ANTICIPATED TOWARDS THE MIDDAY HRS. WIND ADVISORY LENDING
TO ISSUANCE OF AIRPORT WEATHER WARNING.
KBDL TERMINAL...MODERATE CONFIDENCE.
FZRA PERSISTING INTO THE EARLY-MORNING HOURS...THEN CHANGING OVER
TO RAIN. NOT ABSOLUTELY CERTAIN ON TIMING BUT CONFIDENT WITH
TRENDS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE. MVFR/IFR IN
SCATTERED RAIN OR SNOW SHOWERS.
FRIDAY...MODERATE CONFIDENCE. MVFR IN ISOLATED RAIN/SNOW SHOWERS.
SATURDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
5 AM UPDATE...
BASED ON FORECAST CONFIDENCE...HAVE GONE WITH STORM WARNINGS FOR
THE OUTER WATERS WITH THE EXPECTATION OF GUSTS AROUND 45-50 KT.
BUT GREATER CONFIDENCE OF THE INNER-WATERS REACHING HIGH-END GALE
WARNING CRITERIA PERMITTED THE DISCONTINUING OF THE STORM WATCH.
CAN NOT RULE OUT AN ISOLATED GUST UP TO 50 KTS OVER THE INNER-
WATERS...BUT WITH IT NOT ANTICIPATED TO BE WIDESPREAD...KEPT WITH
GALE WARNINGS. STRONGEST E-WINDS OCCURRING TOWARDS THE MIDDAY AND
CONTINUING INTO THE EARLY EVENING HOURS.
SEAS BUILDING 15 TO 20 FEET WITH INCREASING E-WINDS AHEAD OF A
DEEPENING AREA OF LOW PRESSURE OF THE DELMARVA PENINSULA PRESENTLY
AS IT LIFTS N INTO S NEW ENGLAND TOWARDS THIS EVENING. EXPECT
ACCOMPANYING HEAVY RAIN WHICH WILL YIELD VISIBILITY RESTRICTIONS
ON THE WATERS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
SMALL CRAFT ADVISORIES WILL LIKELY NEED TO CONTINUE THROUGH
THURSDAY NIGHT ACROSS THE OCEAN-EXPOSED COASTAL WATERS...MAINLY
DUE TO ROUGH SEAS. THERE COULD ALSO BE SOME WEST/SOUTHWEST GUSTS
UP TO 25 KT AS WELL. ALSO SHOULD SEE LEFTOVER SCATTERED RAIN/SNOW
SHOWERS.
FRIDAY INTO SATURDAY...MODERATE CONFIDENCE.
SLOW IMPROVEMENT CONTINUES WITH DIMINISHING WINDS AND SEAS. SEAS
SHOULD FINALLY DROP BELOW 5 FT ACROSS ALL BUT THE OUTERMOST
COASTAL WATERS FRI EVENING...THEN REMAIN BELOW SMALL CRAFT
ADVISORY THRESHOLDS ACROSS ALL WATERS SATURDAY.
&&
.HYDROLOGY...
STORM-TOTAL RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS EXPECTED THROUGH WEDNESDAY MORNING.
WITH A HARDENED GROUND BY ALL THE RECENT COLD WEATHER...AND THE
COMBINED THREAT OF BOTH LEAF-CLOGGED DRAINS AND THE HIGH TIDE
ALONG THE E-SHORELINE AROUND MIDDAY...HAVE EXPANDED THE FLOOD
WATCH FOR CAPE COD AND NANTUCKET AND CONTINUED THE WATCH OVERALL
WITH THE THREAT OF URBAN AND POOR-DRAINAGE FLOODING. SMALLER
STREAMS AND RIVERS ESPECIALLY ALONG THE COAST COULD SEE FLOODING
AS HIGH TIDE AND SUBSEQUENT SURGE VIA E-WINDS LIMITS DRAINAGE TO
THE OCEAN. RIVERS CONSEQUENTIALLY BACK-FILLING.
MAIN AREA OF FOCUS IS ON AREAS AROUND THE I-95 CORRIDOR AND
TOWARDS THE S/E. WILL ALSO NEED TO KEEP AN EYE OUT FOR THE
POSSIBILITY OF ISOLATED THUNDERSTORMS OVER THE FAR SE WHICH COULD
YIELD LOCALIZED HEAVY RAIN.
LATEST NERFC GUIDANCE BRINGS LOWER CT RIVER AT MIDDLE HADDAM TO
ACTION STAGE...WHICH IS PRIMARILY BASED ON SURGE OF 2 FT INTO
LOWER CT RIVER. WE MAY ALSO SEE SIMILAR SURGE ALONG PAWCATUCK
RIVER NEAR WESTERLY RI WHICH COULD BRING RISES SLIGHTLY HIGHER
THAN CURRENTLY FORECAST.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY CONTINUES FOR EASTERN MA. COMBINATION OF
WINDS / SEAS / SURGE OF AROUND 1.5 TO 2 FEET DURING THE MIDDAY
HIGH-TIDE YIELDS THE LIKELIHOOD OF OBSERVING MINOR COASTAL
FLOODING AND BEACH EROSION FOR E-FACING SHORELINES WHERE SEAS OF
12 TO 15 FEET ARE POSSIBLE.
AS NOTED IN THE HYDROLOGY PORTION ABOVE...LOCAL STREAMS AND
TRIBUTARIES EMPTYING INTO THE SEA COULD SEE BACK-FILLING ISSUES AS
THE HEAVY RAIN IS ANTICIPATED DURING THE TIME OF HIGH-TIDE. COULD
SEE FLOODING ISSUES EXACERBATED FOR EASTERN MA SHORELINE
COMMUNITIES.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ002>004.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ002>004.
MA...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR MAZ007-014>016-
019>024.
FLOOD WATCH THROUGH LATE TONIGHT FOR MAZ005>007-011>022-024.
COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR MAZ007-015-016-019-022-024.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MAZ005-006-011-012.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ003-004-009-010-026.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
MAZ002-008.
RI...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR RIZ006>008.
FLOOD WATCH THROUGH LATE TONIGHT FOR RIZ001>007.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ231>234-251.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ230.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ235>237.
STORM WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...BELK/SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
HYDROLOGY...
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS ALBANY NY
632 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SLOW MOVING COASTAL STORM WILL BRING A VARIETY OF
WINTER WEATHER TO THE REGION FOR TODAY INTO TONIGHT. WHILE MANY
VALLEY AND EASTERN AREAS WILL SEE A TRANSITION OF A WINTRY MIX TO
RAIN...THE PRECIPITATION WILL BE MAINLY SNOW ACROSS THE CATSKILLS
AND ADIRONDACKS...WITH A MODERATE TO HEAVY ACCUMULATION POSSIBLE IN
THESE HIGH TERRAIN AREAS. WITH THE STORM REMAINING CLOSE TO THE
REGION...SOME ADDITIONAL RAIN AND SNOW WILL OCCUR WEDNESDAY INTO
THURSDAY AS WELL...WITH SOME ADDITIONAL SNOW ACCUMULATION POSSIBLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 632 AM EST...A 1007 HPA COASTAL LOW IS CURRENTLY SITUATED
OFF THE COAST OF WALLOPS ISLAND VIRGINIA . THIS LOW IS CONTINUING TO
LIFT NORTHWARD...AND 3 HR PRESSURE FALLS OF IN EXCESS OF 5 MBS ARE
OCCURRING OFF THE COAST OF THE DELAWARE BEACHES. AN UPPER LEVEL
SHORTWAVE TROUGH IS DIVING OUT OF THE GREAT LAKES/MIDWEST
REGION...AND THIS UPPER LEVEL SHORTWAVE WILL BE CAPTURING THE SFC
WAVE...AND CAUSING IT TO BASICALLY STALL JUST OFF THE NEW JERSEY
SHORE TODAY.
A STRONG LOW LEVEL JET IN EXCESS OF 50 KTS IS ADVECTING PLENTY OF
MOISTURE AND WARM AIR ALOFT INTO THE REGION. THE LATEST REGIONAL
MOSAIC RADAR SHOWS A STEADY BATCH OF MODERATE TO HEAVY PRECIP OVER
NORTHERN NJ AND THE NYC METRO AREA...AND THIS PRECIP IS QUICKLY
ADVANCING NORTHWARD INTO OUR AREA. IN ADVANCE OF THIS STEADY
PRECIP...SOME LIGHT FREEZING DRIZZLE/MIST IS OCCURRING...AS THE
LOW LEVELS ARE STARTING TO MOISTEN UP IN ADVANCE OF THE MAIN SLUG
OF PRECIP. WE/VE RECEIVED REPORTS OF ROADS BECOMING SLICK DUE TO
THIS VERY LIGHT FREEZING DRIZZLE FALLING ON SURFACES WITH THE COLD
AIR IN PLACE. A FEW SPS STATEMENTS/SOCIAL MEDIA UPDATES...IN
ADDITION TO OUR ONGOING WSWS...HAVE ADDRESSED THIS FREEZING
DRIZZLE THREAT FOR THE NEXT FEW HOURS.
MODEL SOUNDINGS SUGGEST PRECIP WILL BEGIN AS A WINTRY MIX FOR THE
MID HUDSON VALLEY AND NW CT...AS A WARM NOSE BETWEEN 850 AND 925
HPA WILL BE IN PLACE. AS THIS PRECIP ADVANCES FURTHER NORTH...IT
LOOKS TO BE SNOW/SLEET ACROSS THE CATSKILLS...BUT WILL PROBABLY BE A
SLEET/FREEZING RAIN MIX AS IT REACHES THE CAPITAL REGION AND
TACONICS. WE WILL HAVE TO WATCH OUR SFC TEMPS CLOSELY...AS AN
EXTENDED PERIOD OF FREEZING RAIN COULD CAUSE US TO MAKE DRASTIC
CHANGES TO OUR ONGOING FORECAST. THE LATEST GUIDANCE SUGGEST
FREEZING RAIN...AND NOT SNOW...IS THE FORECAST ISSUE FOR THE
CAPITAL REGION AND POINTS EASTWARD THIS MORNING.
THERE WILL BE A SHARP CUTOFF BETWEEN SNOW VS. WINTRY MIX VS. RAIN.
THE 3KM HRRR SHOWS THAT SNOW SHOULD ACCUMULATE ACROSS THE
CATSKILLS/HELDERBERGS AND POINTS WESTWARD THIS MORNING...BUT ANY
SNOW/SLEET ACCUMULATION WILL BE LIMITED TO JUST A FEW HOURS FOR
THE HUDSON VALLEY...TACONICS AND NW CT...BEFORE PRECIP CHANGES TO
FREEZING RAIN AND THEN A PLAIN RAIN. SFC TEMPS LOOK TO NUDGE JUST
ABOVE FREEZING BY THE MID MORNING FOR THE MID HUDSON VALLEY...AND
LATE MORNING HOURS IN THE CAPITAL REGION. AS STATED
EARLIER...THESE SFC TEMPS WILL HAVE TO BE MONITORED VERY
CLOSELY...TO SEE IF THE SFC TEMPS HANG COLDER LONGER THAN
ANTICIPATED.
FURTHER NORTH...THE PRECIP WILL EXPAND INTO THE MOHAWK VALLEY AND
ADIRONDACKS BY THE EARLY AFTN HOURS. PRECIP LOOKS TO BE MAINLY
SNOW FOR THE MOHAWK VALLEY/ADIRONDACKS...BUT WILL LIKELY MIX FOR
THE SARATOGA/GLENS FALLS AREA. EVEN UP THERE...A CHANGEOVER TO
RAIN LOOKS TO OCCUR DURING THE AFTN HOURS...AS WARM AIR...BOTH AT
THE SFC AND ALOFT...WILL BE MOVING INTO THE AREA.
FURTHER EAST...THE PRECIP WILL CHANGE TO A WINTRY MIX FOR SOUTHERN
VT/BERKSHIRES AS WELL...EVEN ACROSS THE HIGH TERRAIN...AS WARM
AIR ALOFT OF NEARLY 3 DEGREES C MOVES OVER THE AREA FROM THE EAST.
SOME SNOW/SLEET WILL LIKELY ACCUMULATE BEFORE THE CHANGEOVER...BUT
THE CHANGEOVER WILL PREVENT WARNING LEVEL SNOW FROM OCCURRING. SOME
STRONG WINDS ARE POSSIBLE ACROSS THE SRN GREENS...TACONICS AND
BERKSHIRES...WITH SOME GUSTS OF 25-40 MPH POSSIBLE. THE FULL
BRUNT OF THE LOW LEVEL JET DOESN/T LOOK LIKE IT WILL BE ABLE TO
MIX DOWN DUE TO STABLE LOW LEVELS...BUT SOME GUSTS ARE STILL
POSSIBLE...ESP IN AREAS THAT CHANNEL E-SE FLOW WELL. WE WILL
CONTINUE TO MENTION THIS WIND THREAT IN OUR HWO STATEMENT.
AS THE BEST ISENTROPIC LIFT SHIFTS NORTH AND EAST OF THE REGION
THIS EVENING...STEADY PRECIP WILL START TO SHUT OFF ACROSS OUR
AREA. THE SFC LOW WILL BE MEANDERING OVER THE NYC/LONG ISLAND
AREA...AND THE 500 HPA LOW WILL BECOME CUTOFF OVER THE DELMARVA
AREA. AS A RESULT...SOME ADDITIONAL ON AND OFF PRECIP WILL OCCUR
OVERNIGHT DUE TO THE PVA/CYCLONIC FLOW...BUT IT WILL NOT BE
STEADY OR HEAVY. THERE WILL STILL BE SOME ABOVE FREEZING TEMPS
ALOFT...AND THERE MAY EVEN BE A LACK OF ICE NUCLEI IN THE
CLOUDS...AS THE BEST DEEPER AND COLDER CLOUD TOPS SHIFT AWAY FROM
THE AREA. BECAUSE OF THIS...SOME FREEZING RAIN/DRIZZLE MAY
OCCUR...ALONG WITH SOME BURSTS OF SNOW/RAIN/SLEET AS WELL. TEMPS
LOOK TO HOLD STEADY IN THE LOW TO MIDDLE 30S ACROSS THE ENTIRE
REGION.
BECAUSE OF ALL OF THIS...WINTER STORM WARNINGS WERE NOT ISSUED
OUTSIDE THE CATSKILLS/MOHAWK AND SCHOHARIE VALLEY/ADIRONDACKS
BECAUSE WARNING LEVEL SNOWFALL /7 INCHES IN 12 HOURS OR 9 INCHES
IN 24 HOURS/ IS NOT EXPECTED. STILL...A WINTRY MIX...EVEN THOUGH
IT WILL GO OVER TO RAIN...WILL MAKE FOR HAZARDOUS TRAVEL IN THE
CAPITAL REGION/GLENS FALLS AND SARATOGA AREAS/BERKSHIRES/SOUTHERN
VT/...AND THIS IS WHY THE WINTER WEATHER ADVISORY HAS BEEN ISSUED
FOR THESE LOCATIONS. SNOW ACCUMULATION IN THESE AREAS WILL VARY
BASED ON ELEVATION...WITH JUST UP TO A FEW INCHES IN THE VALLEY
AREAS...AND 2 TO 6 INCHES ACROSS THE HIGH TERRAIN. JUST A COATING
TO AN INCH OF SNOW/SLEET/ICE IS EXPECTED FOR THE
POUGHKEEPSIE/KINGSTON AREA AND NW CT...AS PRECIP SHOULD QUICKLY GO
OVER TO RAIN THERE THIS MORNING. HOWEVER...THE FLOOD WATCH REMAINS
IN EFFECT...AS HEAVY RAINFALL MAY LEAD TO SOME FLOOD CONCERNS. SEE
OUR HYDRO DISCUSSION FOR MORE DETAILS ON THIS THREAT.
MEANWHILE... 6 TO 12 INCHES LOOK TO ACCUMULATE IN THE
CATSKILLS...HELDERBERGS...MOHAWK AND SCHOHARIE VALLEYS...AND
ADIRONDACKS. EVEN IN THESE AREAS...SOME SLEET/FREEZING RAIN IS
POSSIBLE AT TIMES...AND VALLEYS WILL BE ON THE LOWER END OF THE
RANGE...WITH THE HIGHEST AMOUNTS IN THE HIGH PEAKS OF THE
CATSKILLS IN THE GREENE COUNTY...AND IN THE HIGHEST PEAKS OF THE
SRN ADIRONDACKS OF WARREN COUNTY. THE SNOW WILL BE RATHER
WET...AND THIS MAY MAKE FOR SOME POWER OUTAGES/DOWNED TREE
LIMBS...ESP CONSIDERING THAT STRONG NORTH WINDS ARE EXPECTED.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
A NEARLY VERTICALLY STACKED LOW OVER NEW ENGLAND WILL KEEP OUR
WEATHER UNSETTLED THROUGH THE SHORT TERM PERIOD.
WHILE DIFFICULT TO ASCERTAIN WHAT WAVE/S/ WILL TRIGGER ADDITIONAL
PRECIPITATION...MOISTURE WILL WRAP IN OFF THE ATLANTIC TO KEEP THE
HIGH PROBABILITIES IN THE FORECAST. THE BEST LOCATIONS WILL BE
ALONG THE I90 CORRIDOR AND POINTS NORTHWARD. AS FOR THERMAL
PROFILES...WE WILL BE COOLING DOWN THE COLUMN WHERE MOST OF THIS
PRECIPITATION WILL BE IN THE FORM OF SNOW. THERE WILL BE SOME
RAIN/SNOW MIXTURE INTO THE VALLEY LOCATIONS DURING THE LATE MORNING
INTO THE MID AFTERNOON HOURS. THE BEST CHANCE FOR ADDITIONAL
ACCUMULATIONS WILL BE INTO THE HIGHER TERRAIN. AS FOR THE
SPECIFIC...
WEDNESDAY...LATEST TRENDS IN THE MODEL GUIDANCE POINT TOWARD A MORE
SIGNIFICANT SURGE OF MOISTURE OFF THE ATLANTIC AS THE MAIN UPPER LOW
REMAINS JUST OFF THE JERSEY SHORE. MOISTURE ADVECTION AND HIGHER
THETA-E /TROWAL/ BACK INTO PORTIONS OF EASTERN NEW YORK AND WESTERN
NEW ENGLAND. SPECIFIC HUMIDITIES REMAIN RATHER HIGH OF 3-4 G/KG SO
WHERE IT DOES SNOW...WE COULD SEE ADDITIONAL ACCUMULATIONS OF SNOW.
PER THE LATEST NCEP MODEL SUITE AND 00Z ECMWF...THIS SEEMS TO LINE
UP FOR OUR NORTHERN HALF OF THE CWFA. ADDITIONAL FINE TUNING WILL
TAKE PLACE AS PER CSTAR RESEARCH...THESE UPPER LOWS ARE QUITE
PROBLEMATIC WITH PROVIDING SPECIFICS WHERE THE HEAVIER QPF WILL FALL.
THURSDAY...AS THE LOW FILLS AND FURTHER REDUCES THE
BAROCLINICITY...THE PRECIP INTENSITY AND AMOUNTS WILL DIMINISH. SO
ADDITIONAL ACCUMULATIONS SHOULD BE RATHER LIGHT THROUGH THE DAY WITH
JUST A COUPLE MORE INCHES OF SNOW...MAINLY INTO THE TERRAIN.
THURSDAY NIGHT...WHILE THE UPPER LOW BEGINS TO SLOWLY MIGRATE
EASTWARD...ITS INFLUENCES WILL CONTINUE ACROSS THE REGION. THIS
WILL RESULT IN CHC-SCT SNOW PROBABILITIES WITH ADDITIONAL LIGHT
ACCUMULATIONS THROUGHOUT THE REGION AS TEMPERATURES WILL BE BELOW
FREEZING.
WE WILL USE A BLENDED APPROACH TO THE MOS TEMPERATURES AS THEY WERE
FAIRLY CLOSE IN VALUES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
WE MAY STILL BE DEALING WITH A CUT-OFF UPPER LEVEL LOW FOR FRIDAY
INTO SATURDAY...BUT THE SYSTEM WILL HAVE LOST ITS BAROCLINICITY BY
THEN RESULTING IN MAINLY SCATTERED SNOW SHOWERS. THE BEST CHANCE FOR
ANY LIGHT MEASURABLE SNOWFALL WILL BE OVER THE HIGHER TERRAIN WEST
AND EAST OF THE HUDSON RIVER VALLEY...AND ESPECIALLY ACROSS THE
SOUTHERN ADIRONDACKS. OUR AREA WILL CONTINUE TO BE UNDER THE
INFLUENCE OF THE CYCLONIC FLOW ASSOCIATED WITH THIS
SYSTEM...ALTHOUGH DRIER AIR WILL GRADUALLY WORK IN FROM THE
WEST...ESPECIALLY ON SATURDAY AS WE SHOULD BE ON THE WESTERN
PERIPHERY OF THE CIRCULATION. SO WILL CONTINUE TO MENTION SLIGHT
CHANCE TO LOW CHC POPS FOR SNOW SHOWERS FRIDAY AND FRIDAY
NIGHT...DECREASING TO SLIGHT CHANCE IN THE VALLEYS FOR SATURDAY.
THERE WILL CONTINUE TO BE A SOMEWHAT BETTER CHANCE FOR A PASSING
SNOW SHOWER OVER THE HIGHER TERRAIN BOTH FRIDAY AND SATURDAY WITH
THE NORTHWEST CYCLONIC FLOW PERSISTING.
IT LOOKS LIKE DRIER WEATHER WILL FINALLY PREVAIL FOR LATE SATURDAY
INTO SUNDAY...ALTHOUGH THE DEGREE OF CLOUD COVER WILL DEPEND ON HOW
QUICKLY THE CUT-OFF LOW MOVES OUT TO SEA. THE ECMWF IS RATHER SLOW
WITH THE DEPARTURE OF THE CUT-OFF...LINGERING CYCLONIC FLOW UNTIL
SUNDAY...WHILE THE GFS HAS AN UPPER LEVEL RIDGE BUILDING IN BY LATE
SATURDAY. AGAIN...THIS WILL HAVE IMPLICATIONS ON CLOUD COVER BUT WE
ARE EXPECTING PRECIP-FREE CONDITIONS ON SUNDAY. DESPITE RISING UPPER
LEVEL HEIGHTS/TEMPS...SURFACE TEMPS ARE ONLY EXPECTED TO BE SLIGHTLY
ABOVE NORMAL DUE TO EXPECTED SHALLOW MIXING THIS TIME OF YEAR.
TRANQUIL WEATHER LOOKS TO CONTINUE INTO MONDAY...WITH HIGH PRESSURE
AT THE SURFACE AND ALOFT FIRMLY ENTRENCHED OVER THE REGION WITH GOOD
AGREEMENT BETWEEN THE ECMWF/GFS. ANOTHER SYSTEM MAY APPROACH FROM
THE WEST FOR MON NT AND TUE. WILL ADD SLIGHT CHC POPS...AS THERE IS
CONSIDERABLE UNCERTAINTY FOR EARLY NEXT WEEK WHETHER A SOUTHERN
STREAM SYSTEM PHASES WITH THE NORTHERN STREAM YET AGAIN...ALBEIT IN
A WEAKER STATE THAN THIS WEEK.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
A SIGNIFICANT DEVELOPING COASTAL STORM WITH MULTIPLE PRECIPITATION
TYPES WILL IMPACT THE AREA TODAY THROUGH WEDNESDAY.
SPOTTY FREEZING DRIZZLE WILL AFFECT THE TAF SITES UNTIL THE STEADIER
PRECIPITATION ARRIVES FROM SOUTH TO NORTH BETWEEN 12Z-15Z/TUE. ONCE
IT ARRIVES...EACH TAF SITE WILL EXPERIENCE VARYING PRECIPITATION
TYPES. MAINLY IFR/LIFR CONDITIONS ARE EXPECTED ABOUT 1-2 HOURS AFTER
THE STEADIER PRECIP BEGINS. HERE ARE SOME SPECIFICS...
KGFL...STEADY MIX OF SNOW/SLEET SHOULD DEVELOP BETWEEN 14Z-16Z/TUE.
THIS SHOULD PERSIST FOR ABOUT 2 HOURS...BEFORE TRANSITIONING TO
MAINLY A FREEZING RAIN/SLEET MIX BETWEEN 17Z-19Z/TUE. FREEZING RAIN
AND SLEET...MODERATE TO HEAVY AT TIMES...SHOULD THEN CHANGE TO PLAIN
RAIN BETWEEN 22Z/TUE-00Z/WED...AND GRADUALLY DECREASE IN INTENSITY.
OCCASIONAL LIGHT RAIN...POSSIBLY CHANGING BACK TO SLEET OR WET
SNOW...WILL LINGER THROUGH 12Z/WED.
KALB...PATCHY FREEZING DRIZZLE SHOULD TRANSFORM TO STEADIER FREEZING
RAIN AND SLEET BETWEEN 13Z-15Z/TUE. SOME WET SNOW COULD BE MIXED IN
AT TIMES...ESP AT THE ONSET. THEN...MAINLY A FREEZING RAIN AND SLEET
MIX...MODERATE TO HEAVY AT TIMES...WILL PERSIST THROUGH AROUND
19Z-21Z/TUE...BEFORE CHANGING TO PLAIN RAIN AND SOME SLEET. RAIN AND
SLEET SHOULD CHANGE TO OCCASIONAL LIGHT RAIN OR DRIZZLE BETWEEN
01Z-03Z/WED. SOME SNOW COULD MIX BACK IN AFTER 05Z/WED.
KPOU...A PERIOD OF FREEZING RAIN AND SOME SLEET WILL CHANGE TO PLAIN
RAIN BETWEEN 13Z-15Z/TUE...WITH MODERATE TO HEAVY RAIN AT TIMES
EXPECTED THROUGH MUCH OF THE AFTERNOON. RAIN SHOULD BECOME MORE
INTERMITTENT AND LIGHTER AFTER 03Z/WED.
KPSF...PATCHY FREEZING DRIZZLE SHOULD BECOME A STEADY MIX OF SLEET
AND FREEZING RAIN BETWEEN 13Z-15Z/TUE...WITH SOME WET SNOW POSSIBLY
MIXED IN AT TIMES. THIS MIX SHOULD CHANGE TO A PLAIN RAIN/SLEET MIX
BETWEEN 16Z-18Z/TUE...WHICH MAY BE MODERATE TO HVY AT TIMES.
PRECIPITATION SHOULD DECREASE IN INTENSITY BY OR AFTER
05Z/WED...WITH A MIX OF RAIN AND SLEET POSSIBLE.
WINDS WILL INITIALLY BE N-NE AROUND 5-10 KTS...INCREASING TO 10-15
KTS WITH GUST NEAR OR EXCEEDING 20-25 KTS BY THIS AFTERNOON AND INTO
TONIGHT.
OUTLOOK...
WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SN.
THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A FLOOD WATCH REMAINS IN EFFECT FOR LITCHFIELD COUNTY
CONNECTICUT...DUTCHESS COUNTY NEW YORK AND EASTERN ULSTER COUNTY
NEW YORK...FOR THIS MORNING THROUGH TONIGHT.
A COASTAL STORM WILL BRING WIDESPREAD PRECIPITATION TO THE AREA
FOR TODAY INTO TONIGHT. FOR NORTHWESTERN AND HIGH TERRAIN
AREAS...THIS PRECIPITATION WILL FALL PRIMARY AS SNOW OR A WINTRY
MIX. MEANWHILE...ACROSS SOUTHERN AND VALLEY AREAS...PRECIP WILL
BEGIN AS A PERIOD OF SNOW OR A WINTRY MIX AND TRANSITION TO RAIN.
TOTAL LIQUID EQUIVALENT VALUES WILL BE 0.50 OVER THE WESTERN
ADIRONDACKS TO NEARLY 2.00 INCHES OVER WESTERN NEW ENGLAND. WITH
MUCH OF THIS FALLING AS RAINFALL OVER LITCHFIELD COUNTY AND THE
MID HUDSON VALLEY...THERE WILL BE A LOT OF RUNOFF...ESPECIALLY
DURING LATE THIS MORNING THROUGH EARLY THIS EVENING WHEN PRECIP
WILL BE HEAVIEST. THIS RAINFALL MAY LEAD TO MINOR FLOODING OF POOR
DRAINAGE AND LOW LYING AREAS...ESPECIALLY IN AREAS WHERE THE
GROUND IS FROZEN. RISES ON RIVERS AND STREAMS ARE LIKELY...AND
MINOR FLOODING CANNOT BE RULED OUT ON THE HOUSATONIC RIVER AND
IT/S TRIBUTARIES IN NW CT.
IN ADDITION...THE STRONG COASTAL LOW IS ALLOWING FOR SOME TIDAL
FLOODING ALONG COASTAL AREAS...AND THIS COULD CAUSE A BACKUP OF
WATER ON THE HUDSON RIVER. THIS COULD LEAD TO MINOR FLOODING
DURING TIMES OF HIGH TIDE IN THE POUGHKEEPSIE AREA THIS AFTERNOON.
SOME ADDITIONAL PRECIPITATION...MAINLY IN THE FORM OF SNOW...IS
POSSIBLE FOR WEDNESDAY INTO THURSDAY...BUT AMOUNTS ARE EXPECTED TO
BE LIGHT IN AREAS THAT SEE THE HEAVIEST LIQUID PRECIP TODAY. THIS
SHOULD ALLOW WATER LEVELS TO RECEDE SLOWLY OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ001-013.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ001-013.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ032-033-
038>040-042-043-047-048-051-058-063-082.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ041-
049-050-052>054-059>061-083-084.
FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ064>066.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ064>066.
MA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-
025.
VT...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...BGM
LONG TERM...KL/JPV
AVIATION...KL/JPV
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
528 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SIGNIFICANT COASTAL STORM WILL IMPACT THE REGION TODAY WITH
WINTRY PRECIPITATION AND HEAVY RAIN...ALONG WITH STRONG TO
DAMAGING WINDS. LEFTOVER LIGHT SNOW AND RAIN SHOWERS WILL PERSIST
WEDNESDAY AND THURSDAY. SLOW IMPROVEMENT IS EXPECTED FRI INTO THIS
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
*/ HIGHLIGHTS...
- WINTRY PRECIPITATION TYPES ERODING WITH TIME TO THE N/W
- SNOW / ICE ACCUMULATIONS REMAIN AT WINTER-WX-ADVISORY LEVELS
- HEAVY RAIN OF 2-3 INCHES LENDING TO POSSIBLE FLOODING
- STRONG TO DAMAGING E-WINDS YIELDING WIND ADV HEADLINES
*/ SYNOPTICALLY...
PRESENT OFFSHORE LOW OFF THE MID-ATLANTIC CONUS BECOMES USURPED BY
AN AMPLIFYING TROUGH DIGGING THROUGH THE E-CONUS. ACROSS A REGION OF
FAVORABLE BAROCLINICITY / ATTENDANT DYNAMICS / STRONG FORCING AND
DEEP-LAYER ASCENT YIELDS A RAPIDLY DEEPENING AREA OF LOW PRESSURE
OFF THE DELMARVA PENINSULA THIS MORNING LIFTING N INTO S NEW ENGLAND
BY EVENING. THE LOW BECOMES STALLED AND CUTOFF FROM THE MEAN FLOW UP
AGAINST HIGH PRESSURE ON NEARLY ALL SIDES AS WE GO INTO THE WEEK.
*/ HEAVY RAIN AND FLOODING...
INTERROGATING DEEPER...AS THE LOW DEEPENS...EXPECT DECENT LOW-LEVEL
TROWALING OF THE WARM-CONVEYER-BELT BENEATH THE RRQ/LFQ OF
ATTENDANT UPPER-LEVEL JET AXES. COMBINATION OF THE CONVERGENT
LEADING NOSE OF ISENTROPIC UPSLOPE LENDING TO THE TIGHTENING OF
THE THERMAL GRADIENT AGAINST NEIGHBORING HIGH PRESSURE YIELDING
STRONG FRONTOGENETICAL FORCING IN A REGION OF MINOR -EPV
INSTABILITY BENEATH AFOREMENTIONED DEEP-LAYER ASCENT LIKELY TO
RESULT IN A ROUGHLY W-E BANDING SETUP OF HIGHER WSR-88D RETURNS
WITHIN A WIDESPREAD COMMA-SHAPED PRECIP FIELD ALONG THE
N-PERIPHERY OF THE H85 LOW WITH THE FRONT-END THUMP OF PRECIP
ANTICIPATED AROUND MIDDAY AND PERSISTING INTO EARLY EVENING.
WHEW...DEEP BREATH. FEEL THE HRRR SIMULATED RADAR TRENDS ARE
SHOWING THIS QUITE WELL.
WILL EXPAND THE FLOOD WATCH TO INCLUDE CAPE COD AND NANTUCKET.
WITH HEIGHT OF THE E/NE-WINDS AND HEAVY RAIN CONCURRENT WITH TIMING
OF HIGH TIDE CENTERED AROUND 1 PM BELIEVE SURGE ALONG WITH BUILDING
WAVE HEIGHTS /SEE THE MARINE DISCUSSION BELOW FOR MORE DETAILS/ WILL
RESULT IN POOR-DRAINAGE ISSUES FOR COASTAL COMMUNITIES. ANTICIPATE
DRAINS TO BACK-UP BECOMING OVER-TOPPED RESULTING IN SUSCEPTIBLE LOW-
LYING AND POOR-DRAINAGE AREAS TO BECOME FLOODED.
AM ALSO CONCERNED FOR EVEN THOSE COMMUNITIES WITHIN THE COASTAL
PLAIN IN VICINITY OF RIVERS THAT ARE INFLUENCED BY THE TIDE /I.E.
TAUNTON RIVER...LOWER CONNECTICUT/. COULD ALSO SEE SOME EXACERBATED
FLOOD ISSUES FOR THESE AREAS.
OTHERWISE REMAINDER OF THE FLOOD WATCH REMAINS IN PLACE. PWATS OF
1.25-INCHES FORECAST /ROUGHLY +2 STANDARD DEVIATIONS ABOVE-NORMAL/
AND FORECAST RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS ANTICIPATED. GROUND IS PRETTY SOLID /IMPERVIOUS/ THUS EXPECT
MOST OF THE RAINFALL TO BECOME RUNOFF. MAJORITY OF MAINSTEM RIVERS
OVER THE INTERIOR SHOULD BE ABLE TO HANDLE THE RAIN...SO CONCERNS
LIE IN THE REALM OF URBAN / POOR DRAINAGE FLOODING...ESPECIALLY IF
DRAINS ARE STILL LEAF-CLOGGED. BIGGEST AREA OF CONCERN IS WITHIN THE
METRO-AREA CORRIDORS...ESPECIALLY BOSTON-PROVIDENCE. MAY NEED TO
EXPAND THE WATCH ACROSS N-CENTRAL AND NW MA PENDING THE TIMING AT
WHICH WINTRY-PRECIP TYPES TRANSITION TO RAIN.
*/ WINTRY PRECIPITATION...
OUTCOMES DEPENDENT ON THERMAL FIELDS ALOFT...WHERE AROUND H925-H85
BY MORNING CONDITIONS ARE WARMING CONSIDERABLY UP AGAINST COLDER AIR
AND HIGH PRESSURE SITUATED N/W. A SW-NE FREEZING LINE AROUND NW-CT
INTO S NH INITIALLY MODIFIES NW AS THE LOW DEEPENS RESULTING IN THE
INCREASE OF THE SE WARM-MOIST-CONVEYER-BELT. EXPECT THICKNESSES
TO GRADUALLY RISE DURING THE HEIGHT OF THE EVENT INTO EVENING.
AT THE SURFACE...AREAS BELOW FREEZING ERODE WITH INCREASING ONSHORE
E/NE-WINDS DURING THE MORNING /MORE ON THAT LATER/. UNCERTAINTY
CONTINUES WITH 09.0Z HIGH-RES MODELS DIFFERING IN TIMING OF EROSION.
AS MENTIONED IN PRIOR DISCUSSIONS...FOR AREAS THAT ARE WITHIN OR
ON THE CUSP OF BELOW-FREEZING TEMPERATURES BY 1-2C...LINGERING AN
HOUR OR TWO MORE OR LESS CAN MAKE ALL THE DIFFERENCE WITH REGARDS
TO WINTER-WEATHER HEAD-LINES. H975-925 AGEOSTROPHIC FLOW IS
NOTABLY PERSISTENT AND STRONG OUT OF THE W AS THE LOW INTENSIFIES
TOWARDS S NEW ENGLAND. BUT NOT MUCH OF A N-COMPONENT NOR FROM
ARCTIC-SOURCE REGIONS...SO BELIEVE THIS WILL DO LITTLE TO MAINTAIN
/ PERSIST COLD AIR OVER THE REGION AGAINST STRONG ONSHORE E-FLOW.
WILL GO CLOSE TO THE NEAR-TERM HIGH-RES GUIDANCE WHILE INCORPORATING
THE WRF-NMM WITH REGARDS TO THERMAL FIELDS...WHICH ARE HANDLING THE
SURFACE TEMPERATURES DECENTLY. PREFERENCE TO THE 09.0Z ECMWF IS ALSO
GIVEN ESPECIALLY WHEN EVALUATING H100-H85 THICKNESSES. ONLY WRF-ARW
AND RAP LEAN ON THE WARM SIDE OF THE GUIDANCE OVER ALL OTHERS.
ALSO WILL GO WITH A TOP-DOWN APPROACH TOWARDS PRECIPITATION-TYPE
THAT INCORPORATES THE INCREASING MOISTURE FROM THE S WITHIN OR
ABOVE THE DENDRITIC GROWTH ZONE REGION.
SO OVERALL...EXPECTING THE GRADUAL EROSION OF THE COASTAL-FRONT WITH
INCREASING ONSHORE E-FLOW. PUSH OF WARMER AIR ALOFT AHEAD OF THE
DEEPENING LOW WILL RESULT IN PRECIP-TYPE TRANSITION FAIRLY QUICKLY
TO A SLEET / FREEZING RAIN MIX. THIS HAS SUBSEQUENTLY BUMPED DOWN
SNOWFALL AMOUNTS RESULTING IN A RANGE OF 2-4 INCHES ACROSS NW MA.
MOST OF THE REGION CHANGES OVER TO RAIN BY LATE MORNING INTO MIDDAY
WITH ONLY THE HIGHER ELEVATIONS OF THE BERKSHIRES CONTINUALLY UNDER
THE THREAT OF FREEZING RAIN.
HAVE DROPPED WINTER-STORM WATCHES AND REPLACED WITH WINTER WEATHER
ADVISORIES. HAVE TRIMMED THE EASTERN-EXTENT WITH EROSION OF THE
COASTAL FRONT AND THE SURGANCE OF WARMER AIR ONSHORE. AGAIN...THE
THERMAL FIELDS DISCUSSION ABOVE GIVE AN INDICATION OF PREFERRED
MODEL GUIDANCE. SHOULD SEE WINTER WEATHER HEADLINES DROP MAINLY
AROUND THE MIDDAY HOURS.
MID-LEVEL DRY-SLOT WRAPPING INTO A DEVELOPING OCCLUSION BEGINNING
TUESDAY EVENING SHOULD RESULT IN A LULL OF PRECIPITATION AS WE GO
INTO WEDNESDAY MORNING.
*/ STRONG TO DAMAGING WINDS...
NOTING E-WINDS 1-2 KFT AGL WILL BE AROUND 55 MPH AROUND THE MIDDAY
INTO AFTERNOON HOURS...THE PRESENCE OF WARMER AIR ALOFT LENDING TO
AN INVERSION JUST ABOVE THE SURFACE MAKES IT DIFFICULT TO CONSIDER A
HIGH WIND WARNING. THIS DESPITE WARMER AIR WIGGLING ITS WAY UP FROM
THE S AT THE SURFACE...AND A WARMER OCEAN /THOUGH NOW AROUND THE LOW-
50S/. BOUNDARY-LAYER MIXING WILL BE LIMITED. HIGH-END WIND ADVISORY
CRITERIA IS EXPECTED...BUT DO NOT EXPECT WIDESPREAD GUSTS EXCEEDING
HIGH WIND WARNING CRITERIA. THUS WENT WITH THE WIND ADVISORY.
COULD PRECIPITATION-DRAG PROCESSES BRING FASTER MOMENTUM TO THE
SURFACE? YES...IT IS QUITE POSSIBLE...EVEN IF THUNDERSTORMS ARE IN
THE MIX WHICH IS IN THE FORECAST FOR THE FAR SE-WATERS ADJACENT TO
THE CAPE AND ISLANDS. HAVE GONE WITH THE HEADLINES THAT CONVEY THE
HIGHEST CONFIDENCE.
*/ COASTAL FLOODING...
SEE TIDES/COASTAL FLOODING SECTION BELOW FOR DETAILS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGHLIGHTS...
* LINGERING RAIN/SNOW SHOWERS INTO THU AS CLOSED LOW SLOWLY EXITS
* IMPROVING CONDITIONS FRI INTO THIS WEEKEND
DECENT MODEL AGREEMENT BOTH AT THE SURFACE AND ALOFT WEDNESDAY
INTO FRIDAY. MORE SIGNIFICANT DIFFERENCES ARISE FRIDAY NIGHT INTO
EARLY NEXT WEEK. AS SUCH...FAVORED A CONSENSUS BLEND TO UPDATE
THIS PORTION OF THE FORECAST. THIS WAS TO SMOOTH OVER THE MINOR
DIFFERENCES INTO FRIDAY...AS WELL AS MINIMIZE ERROR AFTER THAT
POINT.
CLOSED LOW WILL BE SLOW TO EXIT NEW ENGLAND...AND 09/00Z GUIDANCE
MODELS CONTINUE TO SHOW A DEEP UPPER LOW OVER NORTHERN NEW ENGLAND
FINALLY MOVING OUT TO SEA SATURDAY NIGHT. ONE OF THE PRIMARY
ISSUES WITH THIS FORECAST WILL BE THE AMOUNT OF MOISTURE
AVAILABLE. THINKING THERE WILL BE ENOUGH TO KEEP SKIES MOSTLY
CLOUD INTO FRIDAY NIGHT. HOW MUCH WILL BE LEFTOVER TO US IN
GENERATING PRECIPITATION IS ANOTHER MATTER. CONTINUED THE PREVIOUS
FORECAST OF A GRADUAL DRYING OUT PROCESS FRIDAY INTO SATURDAY.
HIGH PRESSURE SHOULD BE IN CONTROL OF OUR WEATHER SUNDAY INTO
MONDAY.
NEAR OR SLIGHTLY BELOW NORMAL TEMPERATURES EXPECTED THROUGH THIS
PERIOD.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH WEDNESDAY MORNING/...
10Z UPDATE...
TODAY INTO TONIGHT...MODERATE CONFIDENCE.
MIX OF MVFR-IFR CIGS / VSBYS WITH MAINLY +RA. AN ISOLATED TSRA IS
POSSIBLE FOR FAR SE-COASTAL TERMINALS. OTHERWISE GRADUAL EROSION
TO N/W OF FZRA/PL/SN INTO THE EARLY-AFTERNOON HOURS DURING WHICH
TIME WINDS WILL INCREASE OUT OF THE E WITH STRONGEST GUSTS ALONG
THE E-SHORELINE MAINLY AROUND 40 KT WITH LOCALLY HIGHER GUSTS UP
TO 50 KT. WILL ALSO SEE AN ACCOMPANYING LLWS THREAT WITH WINDS
AROUND 2 KFT AGL OUT OF THE E AROUND 60 KTS.
KBOS TERMINAL...MODERATE CONFIDENCE.
FEEL CONFIDENT WITH TRENDS BUT NOT SO MUCH WITH SPECIFICS. HIGH
CONFIDENCE OF CONTINUED +RA WITH INCREASING E-WINDS. GUSTS UP TO
40 KT ANTICIPATED TOWARDS THE MIDDAY HRS. WIND ADV LENDING TO
ISSUANCE OF AWW.
KBDL TERMINAL...MODERATE CONFIDENCE.
FZRA PERSISTING INTO THE EARLY-MORNING HOURS THEN CHANGING OVER TO
RAIN. NOT ABSOLUTELY CERTAIN ON TIMING BUT CONFIDENT WITH TRENDS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE. MVFR/IFR IN
SCATTERED RAIN OR SNOW SHOWERS.
FRIDAY...MODERATE CONFIDENCE. MVFR IN ISOLATED RAIN/SNOW SHOWERS.
SATURDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
5 AM UPDATE...
BASED ON FORECAST CONFIDENCE...HAVE GONE WITH STORM WARNINGS FOR
THE OUTER WATERS WITH THE EXPECTATION OF GUSTS AROUND 45-50 KT.
BUT GREATER CONFIDENCE OF THE INNER-WATERS REACHING HIGH-END GALE
WARNING CRITERIA PERMITTED THE DISCONTINUING OF THE STORM WATCH.
CAN NOT RULE OUT AN ISOLATED GUST UP TO 50 KTS OVER THE INNER-
WATERS...BUT WITH IT NOT ANTICIPATED TO BE WIDESPREAD...KEPT WITH
GALE WARNINGS. STRONGEST E-WINDS OCCURRING TOWARDS THE MIDDAY AND
CONTINUING INTO THE EARLY EVENING HOURS.
SEAS BUILDING 15 TO 20 FEET WITH INCREASING E-WINDS AHEAD OF A
DEEPENING AREA OF LOW PRESSURE OF THE DELMARVA PENINSULA PRESENTLY
AS IT LIFTS N INTO S NEW ENGLAND TOWARDS THIS EVENING. EXPECT
ACCOMPANYING HEAVY RAIN WHICH WILL YIELD VISIBILITY RESTRICTIONS
ON THE WATERS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
SMALL CRAFT ADVISORIES WILL LIKELY NEED TO CONTINUE THROUGH
THURSDAY NIGHT ACROSS THE OCEAN-EXPOSED COASTAL WATERS...MAINLY
DUE TO ROUGH SEAS. THERE COULD ALSO BE SOME WEST/SOUTHWEST GUSTS
UP TO 25 KT AS WELL. ALSO SHOULD SEE LEFTOVER SCATTERED RAIN/SNOW
SHOWERS.
FRIDAY INTO SATURDAY...MODERATE CONFIDENCE.
SLOW IMPROVEMENT CONTINUES WITH DIMINISHING WINDS AND SEAS. SEAS
SHOULD FINALLY DROP BELOW 5 FT ACROSS ALL BUT THE OUTERMOST
COASTAL WATERS FRI EVENING...THEN REMAIN BELOW SMALL CRAFT
ADVISORY THRESHOLDS ACROSS ALL WATERS SATURDAY.
&&
.HYDROLOGY...
STORM-TOTAL RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS EXPECTED THROUGH WEDNESDAY MORNING.
WITH A HARDENED GROUND BY ALL THE RECENT COLD WEATHER...AND THE
COMBINED THREAT OF BOTH LEAF-CLOGGED DRAINS AND THE HIGH TIDE
ALONG THE E-SHORELINE AROUND MIDDAY...HAVE EXPANDED THE FLOOD
WATCH FOR CAPE COD AND NANTUCKET AND CONTINUED THE WATCH OVERALL
WITH THE THREAT OF URBAN AND POOR-DRAINAGE FLOODING. SMALLER
STREAMS AND RIVERS ESPECIALLY ALONG THE COAST COULD SEE FLOODING
AS HIGH TIDE AND SUBSEQUENT SURGE VIA E-WINDS LIMITS DRAINAGE TO
THE OCEAN. RIVERS CONSEQUENTIALLY BACK-FILLING.
MAIN AREA OF FOCUS IS ON AREAS AROUND THE I-95 CORRIDOR AND
TOWARDS THE S/E. WILL ALSO NEED TO KEEP AN EYE OUT FOR THE
POSSIBILITY OF ISOLATED THUNDERSTORMS OVER THE FAR SE WHICH COULD
YIELD LOCALIZED HEAVY RAIN.
LATEST NERFC GUIDANCE BRINGS LOWER CT RIVER AT MIDDLE HADDAM TO
ACTION STAGE...WHICH IS PRIMARILY BASED ON SURGE OF 2 FT INTO
LOWER CT RIVER. WE MAY ALSO SEE SIMILAR SURGE ALONG PAWCATUCK
RIVER NEAR WESTERLY RI WHICH COULD BRING RISES SLIGHTLY HIGHER
THAN CURRENTLY FORECAST.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY CONTINUES FOR EASTERN MA. COMBINATION OF
WINDS / SEAS / SURGE OF AROUND 1.5 TO 2 FEET DURING THE MIDDAY
HIGH-TIDE YIELDS THE LIKELIHOOD OF OBSERVING MINOR COASTAL
FLOODING AND BEACH EROSION FOR E-FACING SHORELINES WHERE SEAS OF
12 TO 15 FEET ARE POSSIBLE.
AS NOTED IN THE HYDROLOGY PORTION ABOVE...LOCAL STREAMS AND
TRIBUTARIES EMPTYING INTO THE SEA COULD SEE BACK-FILLING ISSUES AS
THE HEAVY RAIN IS ANTICIPATED DURING THE TIME OF HIGH-TIDE. COULD
SEE FLOODING ISSUES EXACERBATED FOR EASTERN MA SHORELINE
COMMUNITIES.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ002>004.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ002>004.
MA...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EST THIS
EVENING FOR MAZ007-014>016-019>024.
FLOOD WATCH THROUGH LATE TONIGHT FOR MAZ005>007-011>022-024.
COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR MAZ007-015-016-019-022-024.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MAZ005-006-011-012.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ003-004-009-010-026.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR MAZ013.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
MAZ002-008.
RI...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EST THIS
EVENING FOR RIZ006>008.
FLOOD WATCH THROUGH LATE TONIGHT FOR RIZ001>007.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR RIZ001-
003.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ231>234-251.
GALE WARNING FROM 10 AM THIS MORNING TO 10 PM EST THIS EVENING
FOR ANZ230.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ236.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ235-237.
STORM WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
HYDROLOGY...SIPPRELL
TIDES/COASTAL FLOODING...SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
451 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SIGNIFICANT COASTAL STORM WILL IMPACT THE REGION TODAY WITH
WINTRY PRECIPITATION AND HEAVY RAIN...ALONG WITH STRONG TO
DAMAGING WINDS. LEFTOVER LIGHT SNOW AND RAIN SHOWERS WILL PERSIST
WEDNESDAY AND THURSDAY. SLOW IMPROVEMENT IS EXPECTED FRI INTO THIS
WEEKEND.
&&
.NEAR TERM /TODAY THROUGH 6 AM WEDNESDAY/...
*/ HIGHLIGHTS...
- WINTRY PRECIPITATION TYPES ERODING WITH TIME TO THE N/W
- SNOW / ICE ACCUMULATIONS REMAIN AT WINTER-WX-ADVISORY LEVELS
- HEAVY RAIN OF 2-3 INCHES LENDING TO POSSIBLE FLOODING
- STRONG TO DAMAGING E-WINDS YIELDING WIND ADV HEADLINES
*/ SYNOPTICALLY...
PRESENT OFFSHORE LOW OFF THE MID-ATLANTIC CONUS BECOMES USURPED BY
AN AMPLIFYING TROUGH DIGGING THROUGH THE E-CONUS. ACROSS A REGION OF
FAVORABLE BAROCLINICITY / ATTENDANT DYNAMICS / STRONG FORCING AND
DEEP-LAYER ASCENT YIELDS A RAPIDLY DEEPENING AREA OF LOW PRESSURE
OFF THE DELMARVA PENINSULA THIS MORNING LIFTING N INTO S NEW ENGLAND
BY EVENING. THE LOW BECOMES STALLED AND CUTOFF FROM THE MEAN FLOW UP
AGAINST HIGH PRESSURE ON NEARLY ALL SIDES AS WE GO INTO THE WEEK.
*/ HEAVY RAIN AND FLOODING...
INTERROGATING DEEPER...AS THE LOW DEEPENS...EXPECT DECENT LOW-LEVEL
TROWALING OF THE WARM-CONVEYOR-BELT BENEATH THE RRQ/LFQ OF
ATTENDANT UPPER-LEVEL JET AXES. COMBINATION OF THE CONVERGENT
LEADING NOSE OF ISENTROPIC UPSLOPE LENDING TO THE TIGHTENING OF
THE THERMAL GRADIENT AGAINST NEIGHBORING HIGH PRESSURE YIELDING
STRONG FRONTOGENETICAL FORCING IN A REGION OF MINOR -EPV
INSTABILITY BENEATH AFOREMENTIONED DEEP-LAYER ASCENT LIKELY TO
RESULT IN A ROUGHLY W-E BANDING SETUP OF HIGHER WSR-88D RETURNS
WITHIN A WIDESPREAD COMMA-SHAPED PRECIP FIELD ALONG THE
N-PERIPHERY OF THE H85 LOW WITH THE FRONT-END THUMP OF PRECIP
ANTICIPATED AROUND MIDDAY AND PERSISTING INTO EARLY EVENING.
WHEW...DEEP BREATH. FEEL THE HRRR SIMULATED RADAR TRENDS ARE
SHOWING THIS QUITE WELL.
WILL EXPAND THE FLOOD WATCH TO INCLUDE CAPE COD AND NANTUCKET.
WITH HEIGHT OF THE E/NE-WINDS AND HEAVY RAIN CONCURRENT WITH TIMING
OF HIGH TIDE CENTERED AROUND 1 PM BELIEVE SURGE ALONG WITH BUILDING
WAVE HEIGHTS /SEE THE MARINE DISCUSSION BELOW FOR MORE DETAILS/ WILL
RESULT IN POOR-DRAINAGE ISSUES FOR COASTAL COMMUNITIES. ANTICIPATE
DRAINS TO BACK-UP BECOMING OVER-TOPPED RESULTING IN SUSCEPTIBLE LOW-
LYING AND POOR-DRAINAGE AREAS TO BECOME FLOODED.
AM ALSO CONCERNED FOR EVEN THOSE COMMUNITIES WITHIN THE COASTAL
PLAIN IN VICINITY OF RIVERS THAT ARE INFLUENCED BY THE TIDE /I.E.
TAUNTON RIVER...LOWER CONNECTICUT/. COULD ALSO SEE SOME EXACERBATED
FLOOD ISSUES FOR THESE AREAS.
OTHERWISE REMAINDER OF THE FLOOD WATCH REMAINS IN PLACE. PWATS OF
1.25-INCHES FORECAST /ROUGHLY +2 STANDARD DEVIATIONS ABOVE-NORMAL/
AND FORECAST RAINFALL AMOUNTS OF 2-3 INCHES WITH LOCALLY HIGHER
AMOUNTS ANTICIPATED. GROUND IS PRETTY SOLID /IMPERVIOUS/ THUS EXPECT
MOST OF THE RAINFALL TO BECOME RUNOFF. MAJORITY OF MAINSTEM RIVERS
OVER THE INTERIOR SHOULD BE ABLE TO HANDLE THE RAIN...SO CONCERNS
LIE IN THE REALM OF URBAN / POOR DRAINAGE FLOODING...ESPECIALLY IF
DRAINS ARE STILL LEAF-CLOGGED. BIGGEST AREA OF CONCERN IS WITHIN THE
METRO-AREA CORRIDORS...ESPECIALLY BOSTON-PROVIDENCE. MAY NEED TO
EXPAND THE WATCH ACROSS N-CENTRAL AND NW MA PENDING THE TIMING AT
WHICH WINTRY-PRECIP TYPES TRANSITION TO RAIN.
*/ WINTRY PRECIPITATION...
OUTCOMES DEPENDENT ON THERMAL FIELDS ALOFT...WHERE AROUND H925-H85
BY MORNING CONDITIONS ARE WARMING CONSIDERABLY UP AGAINST COLDER AIR
AND HIGH PRESSURE SITUATED N/W. A SW-NE FREEZING LINE AROUND NW-CT
INTO S NH INITIALLY MODIFIES NW AS THE LOW DEEPENS RESULTING IN THE
INCREASE OF THE SE WARM-MOIST-CONVEYOR-BELT. EXPECT THICKNESSES TO
GRADUALLY RISE DURING THE HEIGHT OF THE EVENT INTO EVENING.
AT THE SURFACE...AREAS BELOW FREEZING ERODE WITH INCREASING ONSHORE
E/NE-WINDS DURING THE MORNING /MORE ON THAT LATER/. UNCERTAINTY
CONTINUES WITH 09.0Z HIGH-RES MODELS DIFFERING IN TIMING OF EROSION.
AS MENTIONED IN PRIOR DISCUSSIONS...FOR AREAS THAT ARE WITHIN OR
ON THE CUSP OF BELOW-FREEZING TEMPERATURES BY 1-2C...LINGERING AN
HOUR OR TWO MORE OR LESS CAN MAKE ALL THE DIFFERENCE WITH REGARDS
TO WINTER-WEATHER HEAD-LINES. H975-925 AGEOSTROPHIC FLOW IS
NOTABLY PERSISTENT AND STRONG OUT OF THE W AS THE LOW INTENSIFIES
TOWARDS S NEW ENGLAND. BUT NOT MUCH OF A N-COMPONENT NOR FROM
ARCTIC-SOURCE REGIONS...SO BELIEVE THIS WILL DO LITTLE TO MAINTAIN
/ PERSIST COLD AIR OVER THE REGION AGAINST STRONG ONSHORE E-FLOW.
WILL GO CLOSE TO THE NEAR-TERM HIGH-RES GUIDANCE WHILE INCORPORATING
THE WRF-NMM WITH REGARDS TO THERMAL FIELDS...WHICH ARE HANDLING THE
SURFACE TEMPERATURES DECENTLY. PREFERENCE TO THE 09.0Z ECMWF IS ALSO
GIVEN ESPECIALLY WHEN EVALUATING H100-H85 THICKNESSES. ONLY WRF-ARW
AND RAP LEAN ON THE WARM SIDE OF THE GUIDANCE OVER ALL OTHERS.
ALSO WILL GO WITH A TOP-DOWN APPROACH TOWARDS PRECIPITATION-TYPE
THAT INCORPORATES THE INCREASING MOISTURE FROM THE S WITHIN OR
ABOVE THE DENDRITIC GROWTH ZONE REGION.
SO OVERALL...EXPECTING THE GRADUAL EROSION OF THE COASTAL-FRONT WITH
INCREASING ONSHORE E-FLOW. PUSH OF WARMER AIR ALOFT AHEAD OF THE
DEEPENING LOW WILL RESULT IN PRECIP-TYPE TRANSITION FAIRLY QUICKLY
TO A SLEET / FREEZING RAIN MIX. THIS HAS SUBSEQUENTLY BUMPED DOWN
SNOWFALL AMOUNTS RESULTING IN A RANGE OF 2-4 INCHES ACROSS NW MA.
MOST OF THE REGION CHANGES OVER TO RAIN BY LATE MORNING INTO MIDDAY
WITH ONLY THE HIGHER ELEVATIONS OF THE BERKSHIRES CONTINUALLY UNDER
THE THREAT OF FREEZING RAIN.
HAVE DROPPED WINTER-STORM WATCHES AND REPLACED WITH WINTER WEATHER
ADVISORIES. HAVE TRIMMED THE EASTERN-EXTENT WITH EROSION OF THE
COASTAL FRONT AND THE SURGANCE OF WARMER AIR ONSHORE. AGAIN...THE
THERMAL FIELDS DISCUSSION ABOVE GIVE AN INDICATION OF PREFERRED
MODEL GUIDANCE. SHOULD SEE WINTER WEATHER HEADLINES DROP MAINLY
AROUND THE MIDDAY HOURS.
MID-LEVEL DRY-SLOT WRAPPING INTO A DEVELOPING OCCLUSION BEGINNING
TUESDAY EVENING SHOULD RESULT IN A LULL OF PRECIPITATION AS WE GO
INTO WEDNESDAY MORNING.
*/ STRONG TO DAMAGING WINDS...
NOTING E-WINDS 1-2 KFT AGL WILL BE AROUND 55 MPH AROUND THE MIDDAY
INTO AFTERNOON HOURS...THE PRESENCE OF WARMER AIR ALOFT LENDING TO
AN INVERSION JUST ABOVE THE SURFACE MAKES IT DIFFICULT TO CONSIDER A
HIGH WIND WARNING. THIS DESPITE WARMER AIR WIGGLING ITS WAY UP FROM
THE S AT THE SURFACE...AND A WARMER OCEAN /THOUGH NOW AROUND THE LOW-
50S/. BOUNDARY-LAYER MIXING WILL BE LIMITED. HIGH-END WIND ADVISORY
CRITERIA IS EXPECTED...BUT DO NOT EXPECT WIDESPREAD GUSTS EXCEEDING
HIGH WIND WARNING CRITERIA. THUS WENT WITH THE WIND ADVISORY.
COULD PRECIPITATION-DRAG PROCESSES BRING FASTER MOMENTUM TO THE
SURFACE? YES...IT IS QUITE POSSIBLE...EVEN IF THUNDERSTORMS ARE IN
THE MIX WHICH IS IN THE FORECAST FOR THE FAR SE-WATERS ADJACENT TO
THE CAPE AND ISLANDS. HAVE GONE WITH THE HEADLINES THAT CONVEY THE
HIGHEST CONFIDENCE.
*/ COASTAL FLOODING...
SEE TIDES/COASTAL FLOODING SECTION BELOW FOR DETAILS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGHLIGHTS...
* LINGERING RAIN/SNOW SHOWERS INTO THU AS CLOSED LOW SLOWLY EXITS
* IMPROVING CONDITIONS FRI INTO THIS WEEKEND
DECENT MODEL AGREEMENT BOTH AT THE SURFACE AND ALOFT WEDNESDAY
INTO FRIDAY. MORE SIGNIFICANT DIFFERENCES ARISE FRIDAY NIGHT INTO
EARLY NEXT WEEK. AS SUCH...FAVORED A CONSENSUS BLEND TO UPDATE
THIS PORTION OF THE FORECAST. THIS WAS TO SMOOTH OVER THE MINOR
DIFFERENCES INTO FRIDAY...AS WELL AS MINIMIZE ERROR AFTER THAT
POINT.
CLOSED LOW WILL BE SLOW TO EXIT NEW ENGLAND...AND 09/00Z GUIDANCE
MODELS CONTINUE TO SHOW A DEEP UPPER LOW OVER NORTHERN NEW ENGLAND
FINALLY MOVING OUT TO SEA SATURDAY NIGHT. ONE OF THE PRIMARY
ISSUES WITH THIS FORECAST WILL BE THE AMOUNT OF MOISTURE
AVAILABLE. THINKING THERE WILL BE ENOUGH TO KEEP SKIES MOSTLY
CLOUD INTO FRIDAY NIGHT. HOW MUCH WILL BE LEFTOVER TO US IN
GENERATING PRECIPITATION IS ANOTHER MATTER. CONTINUED THE PREVIOUS
FORECAST OF A GRADUAL DRYING OUT PROCESS FRIDAY INTO SATURDAY.
HIGH PRESSURE SHOULD BE IN CONTROL OF OUR WEATHER SUNDAY INTO
MONDAY.
NEAR OR SLIGHTLY BELOW NORMAL TEMPERATURES EXPECTED THROUGH THIS
PERIOD.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH WEDNESDAY MORNING/...
4Z UPDATE...
TOWARDS 12Z...
MIX OF MVFR-IFR CIGS WITH IFR VSBYS WITH ANY -SN. OTHERWISE
RUNWAYS BECOMING ICY WITH FZDZ. INCREASING NE-WINDS WITH GUSTS UP
TO 25 KTS ALONG THE IMMEDIATE COASTLINES BY MORNING.
TUESDAY...
STRONG E WINDS AND HEAVY RAIN INTO TUESDAY EVENING WITH
WIDESPREAD MVFR/IFR AND AREAS OF LIFR...ESPECIALLY ACROSS HIGHER
TERRAIN AND NEAR COAST. EAST WINDS 40 KT OR GREATER LIKELY ACROSS
EASTERN MA/S COASTAL RI. LOW RISK OF 50 KT OVER OUTER CAPE COD AND
NANTUCKET...POSSIBLE OUTER CAPE ANN. CONDITIONS SHOULD BEGIN TO
IMPROVE TOWARD EVENING.
KBOS TERMINAL...MODERATE CONFIDENCE.
LOWERED CIGS / VSBYS WITH -SN LIKELY MIXING WITH OR OVER TO FZDZ.
SHOULD SEE CHANGEOVER TO RAIN TOWARDS THE MORNING HOURS THOUGH
TIMING IS NOT ABSOLUTELY CERTAIN. COULD STILL SEE IMPACTS DURING
THE MORNING PUSH.
KBDL TERMINAL...MODERATE CONFIDENCE.
FZDZ LIKELY TO DEVELOP OVER THE NEXT HR OR TWO. WILL SEE A WINTRY
MIX AS WE GO INTO THE MORNING HOURS WITH THE POSSIBILITY OF SNOW
AND SLEET BEFORE CHANGING OVER TO RAIN THROUGH THE MORNING.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE. MVFR/IFR IN
SCATTERED RAIN OR SNOW SHOWERS.
FRIDAY...MODERATE CONFIDENCE. MVFR IN ISOLATED RAIN/SNOW SHOWERS.
SATURDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
11 PM UPDATE...NO CHANGES MADE AT THIS TIME.
PREVIOUS DISCUSSION...
STORM WARNINGS IN EFFECT FOR OUTER S COASTAL WATERS WHERE
CONFIDENCE IS HIGHEST IN REACHING CRITERIA. MAINTAINING STORM
WATCHES ELSEWHERE DUE TO UNCERTAINTY...EXCEPT ISSUING GALE
WARNINGS FOR BOSTON HARBOR AND NARRAGANSETT BAY.
TONIGHT...EXPECT E-NE WIND TO INCREASE AS COASTAL LOW MOVES
NORTH OVERNIGHT. GALE FORCE GUSTS LIKELY RETURNING TO SOUTHERN
WATERS AFTER MIDNIGHT. SEAS ALSO BUILD...AS HIGH AS 8-10 FT ON THE
OUTER WATERS BY DAYBREAK.
TUESDAY...DEEPENING LOW PRES MOVES UP THE EASTERN SEABOARD TOWARD
LONG ISLAND DURING THE DAY. EXPECT WIDESPREAD E GALES WITH AREAS
OF STORM FORCE GUSTS ON THE SOUTHERN OUTER WATERS TUE AFTERNOON
AND EVENING. SEAS RAPIDLY BUILD TO 15-20 FT EASTERN MA WATERS.
HEAVY RAIN LOWERS VSBY...ESPECIALLY LATE TUE MORNING THROUGH THE
AFTERNOON.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
SMALL CRAFT ADVISORIES WILL LIKELY NEED TO CONTINUE THROUGH
THURSDAY NIGHT ACROSS THE OCEAN-EXPOSED COASTAL WATERS...MAINLY
DUE TO ROUGH SEAS. THERE COULD ALSO BE SOME WEST/SOUTHWEST GUSTS
UP TO 25 KT AS WELL. ALSO SHOULD SEE LEFTOVER SCATTERED RAIN/SNOW
SHOWERS.
FRIDAY INTO SATURDAY...MODERATE CONFIDENCE.
SLOW IMPROVEMENT CONTINUES WITH DIMINISHING WINDS AND SEAS. SEAS
SHOULD FINALLY DROP BELOW 5 FT ACROSS ALL BUT THE OUTERMOST
COASTAL WATERS FRI EVENING...THEN REMAIN BELOW SMALL CRAFT
ADVISORY THRESHOLDS ACROSS ALL WATERS SATURDAY.
&&
.HYDROLOGY...
STORM TOTAL RAINFALL OF 2 TO 3 INCHES EXPECTED ACROSS MUCH OF
REGION THROUGH WED MORNING. MAIN CONCERN IS FOR SIGNIFICANT URBAN
FLOODING...ESPECIALLY NEAR I-95 CORRIDOR FROM PROVIDENCE TO BOSTON
WHICH INCLUDES MORE FLOOD PRONE AREAS OF NEW BEDFORD...FALL RIVER
AND PEABODY.
LATEST NERFC GUIDANCE BRINGS LOWER CT RIVER AT MIDDLE HADDAM TO
ACTION STAGE...WHICH IS PRIMARILY BASED ON SURGE OF 2 FT INTO
LOWER CT RIVER. WE MAY ALSO SEE SIMILAR SURGE ALONG PAWCATUCK
RIVER NEAR WESTERLY RI WHICH COULD BRING RISES SLIGHTLY HIGHER
THAN CURRENTLY FORECAST.
&&
.TIDES/COASTAL FLOODING...
WE WENT AHEAD AND ISSUED A COASTAL FLOOD ADVISORY FOR THE EASTERN MA
COAST FOR THE TUESDAY MIDDAY HIGH TIDE CYCLE. APPEARS WINDS/SEAS
WILL BE RAMPING UP AS THE TUE MIDDAY HIGH TIDE APPROACHES. THIS A
RESULT OF INTENSIFYING LOW PRESSURE OVER THE MID ATLANTIC LIFTING
TOWARDS SOUTHERN NEW ENGLAND. AS THE PRESSURE GRADIENT INCREASES
SHOULD SEE NORTHEAST WIND GUSTS OF 40 TO 50 MPH DEVELOP TOWARDS THE
TUE MIDDAY HIGH TIDE. STORM SURGE GUIDANCE APPEARS SLOW TO CATCH
ON...SO INCREASED IT SOME AND EXPECT A 2+ FOOT STORM SURGE DURING
THE HIGH TIDE. THIS SHOULD BE ENOUGH TO RESULT IN MINOR COASTAL
FLOODING ALONG WITH SOME MINOR BEACH EROSION ACROSS THE EASTERN MA
COAST. SEAS MAY EVENTUALLY COME UP TO 20 FEET ACROSS OUR EASTERN
WATERS...BUT THIS SHOULD BE SEVERAL HOURS AFTER THE HIGH TIDE. THAT
IS WHY WE EXPECT MAINLY MINOR COASTAL FLOODING...AS OPPOSED TO A
MORE SIGNIFICANT EVENT.
WERE NOT REALLY CONCERNED ABOUT THE LATE TUESDAY NIGHT OR WEDNESDAY
HIGH TIDES CAUSING PROBLEMS. PRESSURE GRADIENT/WINDS WEAKEN AND
ASTRONOMICAL TIDES CONTINUE TO LOWER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ002>004.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ002>004.
MA...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EST THIS
EVENING FOR MAZ007-014>016-019>024.
FLOOD WATCH THROUGH LATE TONIGHT FOR MAZ005>007-011>022-024.
COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR MAZ007-015-016-019-022-024.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MAZ005-006-011-012.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ003-004-009-010-026.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR MAZ013.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
MAZ002-008.
RI...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EST THIS
EVENING FOR RIZ006>008.
FLOOD WATCH THROUGH LATE TONIGHT FOR RIZ001>007.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR RIZ001-
003.
MARINE...GALE WARNING FROM 7 AM THIS MORNING TO 10 PM EST THIS EVENING
FOR ANZ231>234-251.
GALE WARNING FROM 10 AM THIS MORNING TO 10 PM EST THIS EVENING
FOR ANZ230.
GALE WARNING FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR ANZ236.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR ANZ235-237.
STORM WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
HYDROLOGY...STAFF
TIDES/COASTAL FLOODING...STAFF
AREA FORECAST DISCUSSION
NWS ALBANY NY
420 AM EST TUE DEC 9 2014
.SYNOPSIS...
A SLOW MOVING COASTAL STORM WILL BRING A VARIETY OF
WINTER WEATHER TO THE REGION FOR TODAY INTO TONIGHT. WHILE MANY
VALLEY AND EASTERN AREAS WILL SEE A TRANSITION OF A WINTRY MIX TO
RAIN...THE PRECIPITATION WILL BE MAINLY SNOW ACROSS THE CATSKILLS
AND ADIRONDACKS...WITH A MODERATE TO HEAVY ACCUMULATION POSSIBLE IN
THESE HIGH TERRAIN AREAS. WITH THE STORM REMAINING CLOSE TO THE
REGION...SOME ADDITIONAL RAIN AND SNOW WILL OCCUR WEDNESDAY INTO
THURSDAY AS WELL...WITH SOME ADDITIONAL SNOW ACCUMULATION POSSIBLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 420 AM EST...A DEVELOPING COASTAL LOW IS CURRENTLY SITUATED
OFF THE COAST OF CAPE HATTERAS. THIS LOW IS STARTING TO LIFT
NORTHWARD...AND 3 HR PRESSURE FALLS OF AROUND 5 MBS ARE OCCURRING
OFF THE DELMARVA. AN UPPER LEVEL SHORTWAVE TROUGH IS DIVING OUT OF
THE GREAT LAKES/MIDWEST REGION...AND THIS UPPER LEVEL SHORTWAVE
WILL BE CAPTURING THE SFC WAVE...AND CAUSING IT TO BASICALLY STALL
JUST OFF THE NEW JERSEY SHORE TODAY.
A STRONG LOW LEVEL JET IN EXCESS OF 50 KTS IS ADVECTING PLENTY OF
MOISTURE AND WARM AIR ALOFT INTO THE REGION. THE LATEST REGIONAL
MOSAIC RADAR SHOWS A STEADY BATCH OF MODERATE TO HEAVY PRECIP OVER
NJ...AND THIS PRECIP IS QUICKLY ADVANCING NORTHWARD INTO OUR AREA.
IN ADVANCE OF THIS STEADY PRECIP...SOME LIGHT FREEZING
DRIZZLE/MIST IS OCCURRING...AS THE LOW LEVELS ARE STARTING TO
MOISTEN UP IN ADVANCE OF THE MAIN SLUG OF PRECIP.
MODEL SOUNDINGS SUGGEST PRECIP WILL BEGIN AS A WINTRY MIX FOR THE
MID HUDSON VALLEY AND NW CT...AS A WARM NOSE BETWEEN 850 AND 925
HPA WILL BE IN PLACE. AS THIS PRECIP ADVANCES FURTHER NORTH...IT
LOOKS TO BE SNOW ACROSS THE CATSKILLS...BUT WILL PROBABLY BE A
SNOW/SLEET MIX AS IT REACHES THE CAPITAL REGION AND TACONICS.
THERE WILL BE A SHARP CUTOFF BETWEEN SNOW VS. WINTRY MIX VS. RAIN.
THE 3KM HRRR SHOWS THAT SNOW SHOULD ACCUMULATE ACROSS THE
CATSKILLS/HELDERBERGS AND POINTS WESTWARD THIS MORNING...BUT ANY
SNOW/SLEET ACCUMULATION WILL BE LIMITED TO JUST A FEW HOURS FOR
THE HUDSON VALLEY...TACONICS AND NW CT...BEFORE PRECIP CHANGES TO
A PLAIN RAIN. SFC TEMPS LOOK TO NUDGE JUST ABOVE FREEZING BY THE
MID MORNING FOR THE MID HUDSON VALLEY...AND LATE MORNING HOURS IN
THE CAPITAL REGION. FURTHER NORTH...THE PRECIP WILL EXPAND INTO
THE MOHAWK VALLEY AND ADIRONDACKS BY THE EARLY AFTN HOURS. PRECIP
LOOKS TO BE MAINLY SNOW FOR THE MOHAWK VALLEY/ADIRONDACKS...BUT
WILL LIKELY MIX FOR THE SARATOGA/GLENS FALLS AREA. EVEN UP
THERE...A CHANGEOVER TO RAIN LOOKS TO OCCUR DURING THE AFTN
HOURS...AS WARM AIR...BOTH AT THE SFC AND ALOFT...WILL BE MOVING
INTO THE AREA.
FURTHER EAST...THE PRECIP WILL CHANGE TO A WINTRY MIX FOR SOUTHERN
VT/BERKSHIRES AS WELL...EVEN ACROSS THE HIGH TERRAIN...AS WARM
AIR ALOFT OF NEARLY 3 DEGREES C MOVES OVER THE AREA FROM THE EAST.
SOME SNOW/SLEET WILL LIKELY ACCUMULATE BEFORE THE CHANGEOVER...BUT
THE CHANGEOVER WILL PREVENT WARNING LEVEL SNOW FROM OCCURRING. SOME
STRONG WINDS ARE POSSIBLE ACROSS THE SRN GREENS...TACONICS AND
BERKSHIRES...WITH SOME GUSTS OF 25-40 MPH POSSIBLE. THE FULL
BRUNT OF THE LOW LEVEL JET DOESN/T LOOK LIKE IT WILL BE ABLE TO
MIX DOWN DUE TO STABLE LOW LEVELS...BUT SOME GUSTS ARE STILL
POSSIBLE...ESP IN AREAS THAT CHANNEL E-SE FLOW WELL. WE WILL
CONTINUE TO MENTION THIS WIND THREAT IN OUR HWO STATEMENT.
AS THE BEST ISENTROPIC LIFT SHIFTS NORTH AND EAST OF THE REGION
THIS EVENING...STEADY PRECIP WILL START TO SHUT OFF ACROSS OUR
AREA. THE SFC LOW WILL BE MEANDERING OVER THE NYC/LONG ISLAND
AREA...AND THE 500 HPA LOW WILL BECOME CUTOFF OVER THE DELMARVA
AREA. AS A RESULT...SOME ADDITIONAL ON AND OFF PRECIP WILL OCCUR
OVERNIGHT DUE TO THE PVA/CYCLONIC FLOW...BUT IT WILL NOT BE
STEADY OR HEAVY. THERE WILL STILL BE SOME ABOVE FREEZING TEMPS
ALOFT...AND THERE MAY EVEN BE A LACK OF ICE NUCLEI IN THE
CLOUDS...AS THE BEST DEEPER AND COLDER CLOUD TOPS SHIFT AWAY FROM
THE AREA. BECAUSE OF THIS...SOME FREEZING RAIN/DRIZZLE MAY
OCCUR...ALONG WITH SOME BURSTS OF SNOW/RAIN/SLEET AS WELL. TEMPS
LOOK TO HOLD STEADY IN THE LOW TO MIDDLE 30S ACROSS THE ENTIRE
REGION.
BECAUSE OF ALL OF THIS...WINTER STORM WARNINGS WERE NOT ISSUED
OUTSIDE THE CATSKILLS/MOHAWK AND SCHOHARIE VALLEY/ADIRONDACKS
BECAUSE WARNING LEVEL SNOWFALL /7 INCHES IN 12 HOURS OR 9 INCHES
IN 24 HOURS/ IS NOT EXPECTED. STILL...A WINTRY MIX...EVEN THOUGH
IT WILL GO OVER TO RAIN...WILL MAKE FOR HAZARDOUS TRAVEL IN THE
CAPITAL REGION/GLENS FALLS AND SARATOGA AREAS/BERKSHIRES/SOUTHERN
VT/...AND THIS IS WHY THE WINTER WEATHER ADVISORY HAS BEEN ISSUED
FOR THESE LOCATIONS. SNOW ACCUMULATION IN THESE AREAS WILL VARY
BASED ON ELEVATION...WITH JUST A FEW INCHES IN THE VALLEY
AREAS...AND 2 TO 6 INCHES ACROSS THE HIGH TERRAIN. JUST A COATING TO
AN INCH OF SNOW/SLEET/ICE IS EXPECTED FOR THE POUGHKEEPSIE/KINGSTON
AREA AND NW CT...AS PRECIP SHOULD QUICKLY GO OVER TO RAIN THERE
THIS MORNING. HOWEVER...THE FLOOD WATCH REMAINS IN EFFECT...AS
HEAVY RAINFALL MAY LEAD TO SOME FLOOD CONCERNS. SEE OUR HYDRO
DISCUSSION FOR MORE DETAILS ON THIS THREAT.
MEANWHILE... 6 TO 12 INCHES LOOK TO ACCUMULATE IN THE
CATSKILLS...HELDERBERGS...MOHAWK AND SCHOHARIE VALLEYS...AND
ADIRONDACKS. EVEN IN THESE AREAS...SOME SLEET/FREEZING RAIN IS
POSSIBLE AT TIMES...AND VALLEYS WILL BE ON THE LOWER END OF THE
RANGE...WITH THE HIGHEST AMOUNTS IN THE HIGH PEAKS OF THE
CATSKILLS IN THE GREENE COUNTY...AND IN THE HIGHEST PEAKS OF THE
SRN ADIRONDACKS OF WARREN COUNTY. THE SNOW WILL BE RATHER
WET...AND THIS MAY MAKE FOR SOME POWER OUTAGES/DOWNED TREE
LIMBS...ESP CONSIDERING THAT STRONG NORTH WINDS ARE EXPECTED.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
A NEARLY VERTICALLY STACKED LOW OVER NEW ENGLAND WILL KEEP OUR
WEATHER UNSETTLED THROUGH THE SHORT TERM PERIOD.
WHILE DIFFICULT TO ASCERTAIN WHAT WAVE/S/ WILL TRIGGER ADDITIONAL
PRECIPITATION...MOISTURE WILL WRAP IN OFF THE ATLANTIC TO KEEP THE
HIGH PROBABILITIES IN THE FORECAST. THE BEST LOCATIONS WILL BE
ALONG THE I90 CORRIDOR AND POINTS NORTHWARD. AS FOR THERMAL
PROFILES...WE WILL BE COOLING DOWN THE COLUMN WHERE MOST OF THIS
PRECIPITATION WILL BE IN THE FORM OF SNOW. THERE WILL BE SOME
RAIN/SNOW MIXTURE INTO THE VALLEY LOCATIONS DURING THE LATE MORNING
INTO THE MID AFTERNOON HOURS. THE BEST CHANCE FOR ADDITIONAL
ACCUMULATIONS WILL BE INTO THE HIGHER TERRAIN. AS FOR THE
SPECIFIC...
WEDNESDAY...LATEST TRENDS IN THE MODEL GUIDANCE POINT TOWARD A MORE
SIGNIFICANT SURGE OF MOISTURE OFF THE ATLANTIC AS THE MAIN UPPER LOW
REMAINS JUST OFF THE JERSEY SHORE. MOISTURE ADVECTION AND HIGHER
THETA-E /TROWAL/ BACK INTO PORTIONS OF EASTERN NEW YORK AND WESTERN
NEW ENGLAND. SPECIFIC HUMIDITIES REMAIN RATHER HIGH OF 3-4 G/KG SO
WHERE IT DOES SNOW...WE COULD SEE ADDITIONAL ACCUMULATIONS OF SNOW.
PER THE LATEST NCEP MODEL SUITE AND 00Z ECMWF...THIS SEEMS TO LINE
UP FOR OUR NORTHERN HALF OF THE CWFA. ADDITIONAL FINE TUNING WILL
TAKE PLACE AS PER CSTAR RESEARCH...THESE UPPER LOWS ARE QUITE
PROBLEMATIC WITH PROVIDING SPECIFICS WHERE THE HEAVIER QPF WILL FALL.
THURSDAY...AS THE LOW FILLS AND FURTHER REDUCES THE
BAROCLINICITY...THE PRECIP INTENSITY AND AMOUNTS WILL DIMINISH. SO
ADDITIONAL ACCUMULATIONS SHOULD BE RATHER LIGHT THROUGH THE DAY WITH
JUST A COUPLE MORE INCHES OF SNOW...MAINLY INTO THE TERRAIN.
THURSDAY NIGHT...WHILE THE UPPER LOW BEGINS TO SLOWLY MIGRATE
EASTWARD...ITS INFLUENCES WILL CONTINUE ACROSS THE REGION. THIS
WILL RESULT IN CHC-SCT SNOW PROBABILITIES WITH ADDITIONAL LIGHT
ACCUMULATIONS THROUGHOUT THE REGION AS TEMPERATURES WILL BE BELOW
FREEZING.
WE WILL USE A BLENDED APPROACH TO THE MOS TEMPERATURES AS THEY WERE
FAIRLY CLOSE IN VALUES.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
WE MAY STILL BE DEALING WITH A CUT-OFF UPPER LEVEL LOW FOR FRIDAY
INTO SATURDAY...BUT THE SYSTEM WILL HAVE LOST ITS BAROCLINICITY BY
THEN RESULTING IN MAINLY SCATTERED SNOW SHOWERS. THE BEST CHANCE FOR
ANY LIGHT MEASURABLE SNOWFALL WILL BE OVER THE HIGHER TERRAIN WEST
AND EAST OF THE HUDSON RIVER VALLEY...AND ESPECIALLY ACROSS THE
SOUTHERN ADIRONDACKS. OUR AREA WILL CONTINUE TO BE UNDER THE
INFLUENCE OF THE CYCLONIC FLOW ASSOCIATED WITH THIS
SYSTEM...ALTHOUGH DRIER AIR WILL GRADUALLY WORK IN FROM THE
WEST...ESPECIALLY ON SATURDAY AS WE SHOULD BE ON THE WESTERN
PERIPHERY OF THE CIRCULATION. SO WILL CONTINUE TO MENTION SLIGHT
CHANCE TO LOW CHC POPS FOR SNOW SHOWERS FRIDAY AND FRIDAY
NIGHT...DECREASING TO SLIGHT CHANCE IN THE VALLEYS FOR SATURDAY.
THERE WILL CONTINUE TO BE A SOMEWHAT BETTER CHANCE FOR A PASSING
SNOW SHOWER OVER THE HIGHER TERRAIN BOTH FRIDAY AND SATURDAY WITH
THE NORTHWEST CYCLONIC FLOW PERSISTING.
IT LOOKS LIKE DRIER WEATHER WILL FINALLY PREVAIL FOR LATE SATURDAY
INTO SUNDAY...ALTHOUGH THE DEGREE OF CLOUD COVER WILL DEPEND ON HOW
QUICKLY THE CUT-OFF LOW MOVES OUT TO SEA. THE ECMWF IS RATHER SLOW
WITH THE DEPARTURE OF THE CUT-OFF...LINGERING CYCLONIC FLOW UNTIL
SUNDAY...WHILE THE GFS HAS AN UPPER LEVEL RIDGE BUILDING IN BY LATE
SATURDAY. AGAIN...THIS WILL HAVE IMPLICATIONS ON CLOUD COVER BUT WE
ARE EXPECTING PRECIP-FREE CONDITIONS ON SUNDAY. DESPITE RISING UPPER
LEVEL HEIGHTS/TEMPS...SURFACE TEMPS ARE ONLY EXPECTED TO BE SLIGHTLY
ABOVE NORMAL DUE TO EXPECTED SHALLOW MIXING THIS TIME OF YEAR.
TRANQUIL WEATHER LOOKS TO CONTINUE INTO MONDAY...WITH HIGH PRESSURE
AT THE SURFACE AND ALOFT FIRMLY ENTRENCHED OVER THE REGION WITH GOOD
AGREEMENT BETWEEN THE ECMWF/GFS. ANOTHER SYSTEM MAY APPROACH FROM
THE WEST FOR MON NT AND TUE. WILL ADD SLIGHT CHC POPS...AS THERE IS
CONSIDERABLE UNCERTAINTY FOR EARLY NEXT WEEK WHETHER A SOUTHERN
STREAM SYSTEM PHASES WITH THE NORTHERN STREAM YET AGAIN...ALBEIT IN
A WEAKER STATE THAN THIS WEEK.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
A SIGNIFICANT DEVELOPING COASTAL STORM WITH MULTIPLE PRECIPITATION
TYPES WILL IMPACT THE AREA FROM EARLY TUESDAY MORNING INTO
WEDNESDAY MORNING.
THROUGH 12Z/TUE...A SOLID STRATUS CLOUD DECK HAS ALREADY OVERSPREAD
THE TAF SITES. SOME SPOTTY VERY LIGHT PRECIP HAS ALSO DEVELOPED AT
KPSF...WHERE IFR CIGS ARE PRESENT. WE EXPECT MAINLY IFR
CONDITIONS...MAINLY FOR CIGS...AT KPSF THROUGH 12Z/TUE.
ELSEWHERE...EXPECT MAINLY MVFR CONDITIONS...FOR CIGS...TO PERSIST
THROUGH 12Z/TUE. SOME SPOTTY LIGHT PRECIPITATION...MAINLY IN THE
FORM OF FLURRIES WILL BE POSSIBLE THROUGH 12Z/TUE...ALTHOUGH CAN NOT
RULE OUT A BIT OF FREEZING DRIZZLE...ESP BETWEEN 10Z-12Z/TUE.
AFTER 12Z/TUE...PRECIP ASSOCIATED WITH COASTAL STORM WILL DEVELOP
FROM SOUTH TO NORTH ACROSS THE AREA STARTING SHORTLY 12Z/TUE AT
KPOU...TO MID MORNING AT KGFL. CONDITIONS WILL RAPIDLY DETERIORATE
TO IFR/LIFR SHORTLY AFTER PRECIP COMMENCES.
A WINTRY MIX OF SNOW...SLEET AND FREEZING RAIN IS ANTICIPATED TO
START AT KPOU...CHANGING TO RAIN SHORTLY AFTER SUNRISE. SNOW WILL
DEVELOP AT KALB/KPSF/KGFL AROUND 12Z-14Z/TUE...THEN QUICKLY CHANGE
TO A MIX OF SNOW...SLEET AND FREEZING RAIN AND EVENTUAL RAIN BY NOON
AT KALB/KPSF. MODERATE TO HEAVY RAIN WILL THE FALL THROUGH THE
AFTERNOON AND EARLY TUE NT...POSSIBLY MIXED WITH SLEET. A WINTRY MIX
IS EXPECTED TO PREVAIL WELL INTO THE AFTERNOON AT KGFL BEFORE
POSSIBLY CHANGING TO PLAIN RAIN AND/OR SLEET AFTER 23Z/TUE.
THE PRECIP TYPE FORECASTS AND TIMING ARE LOW CONFIDENCE AT
THIS TIME...AS TEMPERATURE PROFILES IN THE ATMOSPHERE ARE
UNCERTAIN. LOW LEVEL COLD AIR MAY SCOUR OUT QUICKER THAN
ANTICIPATED OR LINGER LONGER INTO THE AFTERNOON...WHICH WOULD
IMPACT WHEN PRECIP TYPE TRANSITIONS OCCUR.
WINDS WILL INITIALLY BE N-NE AROUND 5-10 KTS...INCREASING TO 10-15
KTS WITH GUST NEAR OR EXCEEDING 20 KTS TUESDAY AFTERNOON AND NIGHT.
OUTLOOK...
WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SN.
THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A FLOOD WATCH REMAINS IN EFFECT FOR LITCHFIELD COUNTY
CONNECTICUT...DUTCHESS COUNTY NEW YORK AND EASTERN ULSTER COUNTY
NEW YORK...FOR THIS MORNING THROUGH TONIGHT.
A COASTAL STORM WILL BRING WIDESPREAD PRECIPITATION TO THE AREA
FOR TODAY INTO TONIGHT. FOR NORTHWESTERN AND HIGH TERRAIN
AREAS...THIS PRECIPITATION WILL FALL PRIMARY AS SNOW OR A WINTRY
MIX. MEANWHILE...ACROSS SOUTHERN AND VALLEY AREAS...PRECIP WILL
BEGIN AS A PERIOD OF SNOW OR A WINTRY MIX AND TRANSITION TO RAIN.
TOTAL LIQUID EQUIVALENT VALUES WILL BE 0.50 OVER THE WESTERN
ADIRONDACKS TO NEARLY 2.00 INCHES OVER WESTERN NEW ENGLAND. WITH
MUCH OF THIS FALLING AS RAINFALL OVER LITCHFIELD COUNTY AND THE
MID HUDSON VALLEY...THERE WILL BE A LOT OF RUNOFF...ESPECIALLY
DURING LATE THIS MORNING THROUGH EARLY THIS EVENING WHEN PRECIP
WILL BE HEAVIEST. THIS RAINFALL MAY LEAD TO MINOR FLOODING OF POOR
DRAINAGE AND LOW LYING AREAS...ESPECIALLY IN AREAS WHERE THE
GROUND IS FROZEN. RISES ON RIVERS AND STREAMS ARE LIKELY...AND
MINOR FLOODING CANNOT BE RULED OUT ON THE HOUSATONIC RIVER AND
IT/S TRIBUTARIES IN NW CT.
IN ADDITION...THE STRONG COASTAL LOW IS ALLOWING FOR SOME TIDAL
FLOODING ALONG COASTAL AREAS...AND THIS COULD CAUSE A BACKUP OF
WATER ON THE HUDSON RIVER. THIS COULD LEAD TO MINOR FLOODING
DURING TIMES OF HIGH TIDE IN THE POUGHKEEPSIE AREA THIS AFTERNOON.
SOME ADDITIONAL PRECIPITATION...MAINLY IN THE FORM OF SNOW...IS
POSSIBLE FOR WEDNESDAY INTO THURSDAY...BUT AMOUNTS ARE EXPECTED TO
BE LIGHT IN AREAS THAT SEE THE HEAVIEST LIQUID PRECIP TODAY. THIS
SHOULD ALLOW WATER LEVELS TO RECEDE SLOWLY OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ001-013.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ001-013.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ032-033-
038>040-042-043-047-048-051-058-063-082.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ041-
049-050-052>054-059>061-083-084.
FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ064>066.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ064>066.
MA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-
025.
VT...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...BGM
LONG TERM...KL/JPV
AVIATION...KL/JPV
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1245 AM EST TUE DEC 9 2014
.SYNOPSIS...
AS A SLOW MOVING COASTAL STORM APPROACHES OUR AREA....A
LONG DURATION PERIOD OF RAIN AND SNOW...AND POSSIBLY SLEET AND
FREEZING RAIN...WILL IMPACT THE REGION THROUGH THURSDAY. THE
HEAVIEST PRECIPITATION ASSOCIATED WITH THIS STORM IS EXPECTED THIS
MORNING THROUGH THIS EVENING...BUT LINGERING PERIODS OF
PRECIPITATION ARE POSSIBLE THROUGH MUCH OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM EST...LOW STRATUS CLOUDS ARE IN PLACE OVER THE
REGION THIS MORNING...WITH THE LOWEST CEILINGS CURRENTLY OVER THE
BERKSHIRES. THE LOW LEVELS ARE STARTING TO MOISTEN UP DUE TO A
FLOW OFF THE WESTERN ATLANTIC OCEAN. THERE HASN/T BEEN ANY
PRECIPITATION IN OUR AREA JUST YET...BUT WITH THE INCREASING
MOISTURE IN THE LOWEST LEVELS...SOME FREEZING DRIZZLE IS POSSIBLE
FOR SOUTHERN/EASTERN PARTS OF THE AREA. THIS WILL ESPECIALLY BE
TRUE FOR SOUTHERN/EASTERN FACING SLOPES OF THE BERKSHIRES AND
CATSKILLS...THANKS TO SOME UPSLOPE FLOW. ANY FREEZING DRIZZLE
LOOKS FAIRLY SPOTTY...AND MOST AREAS SHOULD STAY DRY.
THE 02Z 3KM HRRR SHOWS STEADY PRECIP ASSOCIATED WITH A DEVELOPING
COASTAL LOW WILL BE APPROACHING OUR SOUTHERN ZONES BETWEEN 4 AND 6
AM. ACROSS THESE FAR SOUTHERN AREAS...PRECIP LOOKS TO BEGIN AS A
WINTRY MIX OF SNOW/SLEET/FREEZING RAIN. PRECIP WILL QUICKLY START
TO TRANSITION MORE TOWARDS THE WINTRY MIX OR EVEN PLAIN RAIN AS LOW
LEVEL TEMPS RISE...AND A WARM NOSE STARTS TO DEVELOP AT 925 HPA.
TEMPS OVERNIGHT WILL CONTINUE TO BE STEADY IN THE MID TO UPPER
20S...AND MAY EVEN START TO RISE TOWARDS DAYBREAK.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
VERY COMPLEX WINTER STORM WILL HAVE A LARGE IMPACT ON THE REGION
THROUGH THE ENTIRE SHORT TERM PERIOD...ESPECIALLY TUESDAY AND
EARLY TUESDAY NIGHT.
HAVE UPGRADED THE WESTERN AND SOUTHERN ADIRONDACKS...THE MOHAWK
AND SCHOHARIE VALLEYS AND THE EASTERN CATSKILLS TO WINTER STORM
WARNINGS THROUGH 12Z WEDNESDAY...WITH SNOWFALL AMOUNTS OF 7 TO 14
INCHES...ALONG WITH SOME MIXED PCPN POSSIBLE. THE LOWEST TERRAIN
AREAS IN THESE REGIONS MAY NOT EXCEED 7 INCHES OF SNOW DUE TO THE
MIXING OF PCPN WITH SLEET...FREEZING RAIN AND RAIN...BUT ON
AVERAGE MOST AREAS WILL GET HEAVY SNOW.
DUE TO THE EXTREMELY TIGHT GRADIENT IN TEMPERATURES ACROSS THE
REGION...AND THE MINOR TEMPERATURE VARIATIONS THAT OCCUR BETWEEN
EACH MODEL...AND EVEN BETWEEN DIFFERENT RUNS OF THE SAME MODEL...
HAVE DECIDED THAT THERE IS STILL TOO MUCH UNCERTAINTY TO MAKE A
DECISION BETWEEN A WARNING OR AN ADVISORY FOR A LARGE PART OF THE
FORECAST AREA THAT INCLUDES THE SARATOGA REGION...CAPITAL DISTRICT...
THE UPPER PART OF THE MID HUDSON VALLEY...THE TACONICS...SOUTHERN
VERMONT AND BERKSHIRE COUNTY. THIS WAS COORDINATED WITH
SURROUNDING OFFICES TO THE EAST WHO ALSO KEPT ADJOINING PARTS OF
THEIR FORECAST AREAS IN THE WINTER STORM WATCH.
FOR NOW HAVE GENERALLY FORECAST 3 TO 10 INCHES IN THE WATCH
AREA...WITH MOST AREAS GENERALLY FORECAST TO GET 7 INCHES OR LESS...
EXCEPT FOR THE HIGHER TERRAIN OF SOUTHERN VERMONT.
MOST OF THE PCPN WILL OCCUR ON TUESDAY...WITH A LARGE DRY SLOT
SURGING NORTHWARD AND CUTTING OFF THE STEADIEST AND HEAVIEST PCPN
EARLY TUESDAY NIGHT.
WITH THE UPPER LOW EVENTUALLY PARKING ITSELF OVER EASTERN NY...
OCCASIONAL LIGHT SNOW WILL LIKELY CONTINUE WEDNESDAY AND THURSDAY
AS WELL. THERE COULD STILL BE SOME MIXED PCPN WEDNESDAY...BUT ALL
SNOW IS EXPECTED WEDNESDAY NIGHT.
HIGHS TUESDAY WILL BE 30 TO 40. LOWS TUESDAY NIGHT IN THE MID 20S
TO LOWER 30S. HIGHS WEDNESDAY GENERALLY IN THE 30S. LOWS WEDNESDAY
NIGHT 20 TO 30.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
WE WILL STILL BE DEALING WITH A CUT-OFF UPPER LEVEL LOW WHICH WILL
BE CENTERED RIGHT OVER THE REGION ON THURSDAY...BUT THE SYSTEM WILL
HAVE LOST ITS BAROCLINICITY BY THEN RESULTING IN MAINLY SCATTERED TO
LIKELY SNOW SHOWERS. BEST CHANCE FOR ANY LIGHT MEASURABLE SNOWFALL
WILL BE OVER THE HIGHER TERRAIN WEST AND EAST OF THE HUDSON RIVER
VALLEY. THE CUT-OFF LOW WILL ONLY SLOWLY MEANDER TO THE
EAST-NORTHEAST THURSDAY NIGHT INTO FRIDAY...WITH THE CORE MOVING
INTO NEW ENGLAND. OUR AREA WILL CONTINUE TO BE UNDER THE INFLUENCE
OF THE CYCLONIC FLOW ASSOCIATED WITH THIS SYSTEM...ALTHOUGH DRIER
AIR WILL GRADUALLY WORK IN FROM THE WEST...ESPECIALLY ON FRIDAY AS
WE WILL BE ON THE WESTERN PERIPHERY OF THE CIRCULATION. SO WILL
CONTINUE TO MENTION CHANCE POPS FOR SNOW SHOWERS THURSDAY
NIGHT...DECREASING TO SLIGHT CHANCE IN THE VALLEYS FOR FRIDAY. THERE
WILL CONTINUE TO BE A SOMEWHAT BETTER CHANCE FOR A PASSING SNOW
SHOWER OVER THE HIGHER TERRAIN ON FRIDAY WITH THE NORTHWEST CYCLONIC
FLOW PERSISTING.
IT LOOKS LIKE DRIER WEATHER WILL FINALLY PREVAIL FOR THE
WEEKEND...ALTHOUGH THE DEGREE OF CLOUD COVER WILL DEPEND ON HOW
QUICKLY THE CUT-OFF LOW MOVES OUT TO SEA. THE ECMWF IS RATHER SLOW
WITH THE DEPARTURE OF THE CUT-OFF LINGERING CYCLONIC FLOW UNTIL
SUNDAY...WHILE THE GFS HAS AN UPPER LEVEL RIDGE BUILDING IN BY LATE
SATURDAY. AGAIN...THIS WILL HAVE IMPLICATIONS ON CLOUD COVER BUT WE
ARE EXPECTING PRECIP-FREE CONDITIONS THROUGH THE UPCOMING WEEKEND.
DESPITE RISING UPPER LEVEL HEIGHTS/TEMPS...SURFACE TEMPS ARE ONLY
EXPECTED TO BE SLIGHTLY ABOVE NORMAL DUE TO EXPECTED SHALLOW MIXING
THIS TIME OF YEAR.
TRANQUIL WEATHER LOOKS TO CONTINUE INTO MONDAY...WITH HIGH PRESSURE
AT THE SURFACE AND ALOFT FIRMLY ENTRENCHED OVER THE REGION WITH GOOD
AGREEMENT BETWEEN THE ECMWF/GFS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A SIGNIFICANT DEVELOPING COASTAL STORM WITH MULTIPLE PRECIPITATION
TYPES WILL IMPACT THE AREA FROM EARLY TUESDAY MORNING INTO
WEDNESDAY MORNING.
THROUGH 12Z/TUE...A SOLID STRATUS CLOUD DECK HAS ALREADY OVERSPREAD
THE TAF SITES. SOME SPOTTY VERY LIGHT PRECIP HAS ALSO DEVELOPED AT
KPSF...WHERE IFR CIGS ARE PRESENT. WE EXPECT MAINLY IFR
CONDITIONS...MAINLY FOR CIGS...AT KPSF THROUGH 12Z/TUE.
ELSEWHERE...EXPECT MAINLY MVFR CONDITIONS...FOR CIGS...TO PERSIST
THROUGH 12Z/TUE. SOME SPOTTY LIGHT PRECIPITATION...MAINLY IN THE
FORM OF FLURRIES WILL BE POSSIBLE THROUGH 12Z/TUE...ALTHOUGH CAN NOT
RULE OUT A BIT OF FREEZING DRIZZLE...ESP BETWEEN 10Z-12Z/TUE.
AFTER 12Z/TUE...PRECIP ASSOCIATED WITH COASTAL STORM WILL DEVELOP
FROM SOUTH TO NORTH ACROSS THE AREA STARTING SHORTLY 12Z/TUE AT
KPOU...TO MID MORNING AT KGFL. CONDITIONS WILL RAPIDLY DETERIORATE
TO IFR/LIFR SHORTLY AFTER PRECIP COMMENCES.
A WINTRY MIX OF SNOW...SLEET AND FREEZING RAIN IS ANTICIPATED TO
START AT KPOU...CHANGING TO RAIN SHORTLY AFTER SUNRISE. SNOW WILL
DEVELOP AT KALB/KPSF/KGFL AROUND 12Z-14Z/TUE...THEN QUICKLY CHANGE
TO A MIX OF SNOW...SLEET AND FREEZING RAIN AND EVENTUAL RAIN BY NOON
AT KALB/KPSF. MODERATE TO HEAVY RAIN WILL THE FALL THROUGH THE
AFTERNOON AND EARLY TUE NT...POSSIBLY MIXED WITH SLEET. A WINTRY MIX
IS EXPECTED TO PREVAIL WELL INTO THE AFTERNOON AT KGFL BEFORE
POSSIBLY CHANGING TO PLAIN RAIN AND/OR SLEET AFTER 23Z/TUE.
THE PRECIP TYPE FORECASTS AND TIMING ARE LOW CONFIDENCE AT
THIS TIME...AS TEMPERATURE PROFILES IN THE ATMOSPHERE ARE
UNCERTAIN. LOW LEVEL COLD AIR MAY SCOUR OUT QUICKER THAN
ANTICIPATED OR LINGER LONGER INTO THE AFTERNOON...WHICH WOULD
IMPACT WHEN PRECIP TYPE TRANSITIONS OCCUR.
WINDS WILL INITIALLY BE N-NE AROUND 5-10 KTS...INCREASING TO 10-15
KTS WITH GUST NEAR OR EXCEEDING 20 KTS TUESDAY AFTERNOON AND NIGHT.
OUTLOOK...
TUESDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE RA...SN...SLEET.
WEDNESDAY: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SN.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
FRIDAY NIGHT TO SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
FLOOD WATCH FOR DUTCHESS AND EASTERN ULSTER COUNTIES ALONG WITH
LITCHFIELD COUNTY WHERE 1 TO 2 INCHES OF QPF ARE IN THE FORECAST
WITH MAINLY RAIN.
A COASTAL STORM WILL BRING WIDESPREAD PRECIPITATION TO THE REGION
BEGINNING EARLY IN THE DAY ON TUESDAY AND CONTINUING INTO TUESDAY
NIGHT. FOR NORTHWESTERN AND HIGH TERRAIN AREAS...THIS
PRECIPITATION WILL FALL PRIMARY AS SNOW OR A WINTRY MIX.
MEANWHILE...ACROSS SOUTHERN AND VALLEY AREAS...PRECIP WILL BEGIN
AS A PERIOD OF SNOW AND TRANSITION TO A WINTRY MIX AND THEN RAIN.
TOTAL LIQUID EQUIVALENT VALUES WILL BE 0.75 OVER THE WESTERN
ADIRONDACKS TO ABOUT 2 INCHES OVER WESTERN NEW ENGLAND. WITH MUCH
OF THIS FALLING AS RAINFALL OVER LITCHFIELD COUNTY...THERE WILL BE
A LOT OF RUNOFF...ESPECIALLY DURING TUESDAY AFTERNOON INTO TUESDAY
EVENING WHICH PRECIP WILL BE HEAVIEST. THIS RAINFALL MAY LEAD TO
MINOR FLOODING OF POOR DRAINAGE AND LOW LYING AREAS...ESPECIALLY
IN AREAS WHERE THE GROUND IS FROZEN. RISES ON RIVERS AND STREAMS
ARE LIKELY...AND MINOR FLOODING CANNOT BE RULED OUT ON THE
HOUSATONIC RIVER AND IT/S TRIBUTARIES IN NW CT. AS A RESULT...A
FLOOD WATCH IS IN EFFECT FOR LITCHFIELD COUNTY.
ELSEWHERE...MINOR FLOODING OF LOW LYING AREAS CANNOT BE RULED OUT
EITHER...SUCH AS IN THE MID HUDSON VALLEY AND TACONICS...BUT
CONFIDENCE WAS NOT HIGH ENOUGH TO INCLUDE THESE AREAS IN THE FLOOD
WATCH AT THIS TIME. PART OF THIS UNCERTAINTY IS DUE TO QUESTIONS
REMAINING OF HOW LONG PRECIP WILL BE WINTRY VS PLAIN RAINFALL. WHEN
THE EXACT DURATION OF PRECIP TYPES BECOME MORE CLEAR...IT IS
POSSIBLE THAT THE FLOOD WATCH MAY NEED TO BE EXPANDED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH FROM 6 AM EST THIS MORNING THROUGH LATE TONIGHT
FOR CTZ001-013.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
CTZ001-013.
NY...WINTER STORM WARNING FROM 4 AM EARLY THIS MORNING TO 7 AM EST
WEDNESDAY FOR NYZ032-033-038>040-042-043-047-048-051-058-
063-082.
WINTER STORM WATCH FROM 4 AM EST EARLY THIS MORNING THROUGH
WEDNESDAY MORNING FOR NYZ041-049-050-052>054-059>061-083-
084.
FLOOD WATCH FROM 6 AM EST THIS MORNING THROUGH LATE TONIGHT
FOR NYZ064>066.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ064>066.
MA...WINTER STORM WATCH FROM 4 AM EST EARLY THIS MORNING THROUGH
WEDNESDAY MORNING FOR MAZ001-025.
VT...WINTER STORM WATCH FROM 4 AM EST EARLY THIS MORNING THROUGH
WEDNESDAY MORNING FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS/GJM
NEAR TERM...FRUGIS
SHORT TERM...GJM
LONG TERM...JPV
AVIATION...KL/JPV
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
142 PM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE MID-MORNING UPDATE...THE FORECAST FROM EARLIER THIS
MORNING IS BASICALLY ON TRACK BUT HAVE MADE ADJUSTMENTS TO SOME
OF THE HAZARDS. AS OF 900 AM TEMPS ACROSS ALL THE FCST AREA SEEM
TO HAVE RISEN ABOVE FREEZING AND ALL REPORTED PRECIP IS RAIN...SO
THE WINTER WEATHER ADVISORY FOR PARTS OF NW NJ AND ERN PA HAS BEEN
CANCELLED. TEMPS SHOULD CONTINUE TO RISE A COUPLE MORE DEGREES
TODAY. THE WINTER STORM WARNING FOR CARBON AND MONROE COUNTIES
REMAINS IN EFFECT FOR EXPECTED SNOW LATER TONIGHT AND ON
WEDNESDAY.
MEANWHILE...RADAR SHOWS THE AREA OF HEAVIEST RAIN NOW WRAPPING
WWD ACROSS NRN NJ AND INTO ERN PA. THIS AXIS SHOULD CONTINUE TO
SHIFT NWD ALONG WITH THE LOW-LVL STORM CENTER AND BEST EASTERLY
INFLOW. THE FLOOD WATCH AREA HAS BEEN ADJUSTED TO REMOVE AREAS
FROM PHL SWWD...AND ALSO ADD THE TIER OF COUNTIES OVER FAR NW NJ
AND ADJ ERN PA.
PREVIOUS DISCUSSION BELOW...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING AND COASTAL FLOOD ADVISORY...NO LONGER IN
EFFECT.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
LATE DAY AND TONIGHT...LOW-END MVFR TO IFR CONDITIONS AT TIMES WITH
AREAS OF LIGHT RAIN AND/OR SHOWERS. GUSTY NORTH-NORTHWEST WINDS TO
BETWEEN 20 TO 30 KT ARE EXPECTED THROUGH LATE-DAY, BEFORE WINDS BACK
A LITTLE MORE TO THE NORTHWEST AND GUSTS DECREASE SOMEWHAT TO MORE
IN THE 18 TO 24 KNOT RANGE FOR LATE EVENING AND OVERNIGHT. WITH THE
STORM SYSTEM ONLY SLOWLY MOVING AWAY OVERNIGHT, MORE WRAP-AROUND
MOISTURE WILL YIELD SOME BANDS OF RAIN SHIFTING SOUTHEASTWARD ACROSS
THE REGION, WITH RAIN CHANGING TO WET SNOW, ESPECIALLY AT KRDG AND
KABE DURING THE EARLY MORNING HOURS WEDNESDAY. WE ALSO HAVE MEDIUM
CONFIDENCE ON A RAIN/SNOW MIX AND A WINDOW OF A FEW HOURS OF
POSSIBLE WET SNOW TOWARD THE DELAWARE VALLEY TAF SITES, INCLUDING
KPHL, INTO WEDNESDAY MORNING.
WEDNESDAY...CONTINUED RESTRICTIONS IN THE MVFR TO POSSIBLY IFR RANGE
WITH SOME BANDS OF RAIN AND SNOW SHOWERS. GUSTY NORTHWEST WINDS WILL
CONTINUE, WITH GUSTS INCREASING DURING THE DAYTIME, MORE IN THE 23
TO 30 KNOT RANGE.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR
IFR IN BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30
KNOTS AT TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING HAS BEEN CONVERTED TO SMALL CRAFT ADVISORY FOR
COASTAL WATERS SOUTH OF GREAT EGG INLET AND FOR LOWER DELAWARE
BAY. THE GALE WARNING CONTINUES NORTH OF GREAT EGG IN TIGHTER PRES
GRADIENT AHEAD OF DEEPENING SFC LOW AND GALE FORCE NE WINDS. THE
SCA WAS EXTENDED OVERNIGHT AND WILL LIKELY NEED FURTHER EXTENSION
INTO WED FOR ALL WATERS...AS THE SFC LOW IS FCST TO STALL INVOF
LONG ISLAND. WINDS WILL BECOME OFFSHORE OR MORE OFFSHORE RESULTING
IN SMWHT LOWER SEAS WITH THE MORE LIMITED FETCH.
PREVIOUS DISCUSSION BELOW...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
THE FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR FROM PHILLY NORTH.
THE SOUTHERN PORTION OF THE WATCH HAS BEEN CANCELLED WITH THE BULK
OF THE MODERATE TO HEAVY RAIN PUSHING NORTH. FOUR COUNTIES HAVE BEEN
ADDED OF THE NORTHWEST PERIPHERY, LEHIGH NORTHEAST THROUGH SUSSEX AS
THE PRECIPITATION HAS BECOME LIQUID.
THE HEAVIER RAINS WILL CONTINUE INTO THE MID TO LATE AFTERNOON
HOURS BEFORE ENDING. RUNOFF WILL CONTINUE THROUGH THE OVERNIGHT,
LONGER IN SOME SPOTS. ANTECEDENT CONDITIONS ARE WET DUE TO THE
RAINS THE REGION SAW THIS PAST SATURDAY. THIS IS ALLOWING FOR A
MORE EFFICIENT RUNOFF.
WHERE IT RAINS THE HEAVIEST, TOTAL RAINFALL ACCUMULATIONS WILL BE IN
THE 2 TO 3 INCH RANGE. THERE COULD BE SOME TOTALS OVER 3 INCHES.
SMALLER CREEKS AND STREAMS WILL BE THE FIRST BODIES OF WATER TO
RESPOND. THEY ALREADY HAVE. THOSE AREAS WHICH DRAIN INTO TIDAL
WATERS COULD SEE INCREASED FLOODING (IN THE MINOR CATEGORY) DUE TO
HIGHER THAN NORMAL TIDES.
ON THE LARGER BODIES OF WATER THAT ARE SUPPORTED BY THE MARFC, THERE
ARE ABOUT A DOZEN FORECAST POINTS THAT EXCEED CAUTION/ACTION STAGE,
A FEW OF THEM LASTING THROUGH THE NEXT FEW DAYS. THE MAJORITY OF
THESE POINT ARE IN NJ.
AS FOR GAUGES HITTING FLOOD STAGE, WE WILL KEEP AN EYE ON BLACKWELLS
MILLS AND PEMBERTON. IF RUNOFF AND RISES CONTINUE AS EXPECTED INTO
THIS AFTERNOON, FLOOD WARNINGS WILL BE ISSUED LATER TODAY. PEMBERTON
COULD HIT FLOOD STAGE AS EARLY AS THIS EVENING AND BLACKWELLS MILLS
COULD HIT FLOOD STAGE OVERNIGHT TONIGHT.
&&
.TIDES/COASTAL FLOODING...
A WIND SHIFT TO THE NORTH IS EASING AND REVERSING THE POSITIVE TIDAL
ANOMALIES ALONG THE COAST AND ASSOCIATED BACK BAYS, AND THE DELAWARE
BAY TOO. WATER LEVELS ALONG THE COAST PEAKED AT OR JUST BELOW THE
MODERATE THRESHOLD AT HIGH TIDE THIS MORNING/EARLY AFTERNOON, AND
WITH DECREASING ANOMALIES AND LOWER ASTRONOMICAL TIDES DURING THE
NEXT HIGH TIDE CYCLE, NO SIGNIFICANT TIDAL PROBLEMS ARE EXPECTED
TONIGHT. EVEN ON THE UPPER DELAWARE BAY, WATER LEVELS PEAKED BELOW
EVEN THE MINOR FLOOD THRESHOLD AT REEDY POINT EARLY THIS AFTERNOON.
WITH A GRADUAL WIND SHIFT TO THE NORTHWEST EXPECTED THROUGH THE
OVERNIGHT HOURS AS THE COASTAL LOW CONTINUES ITS SLOW NORTHWARD
MOVEMENT, ANY ADDITIONAL FLOODING IS EXPECTED TO BE MINOR IN NATURE.
THE COASTAL FLOOD WARNINGS AND ADVISORIES ARE THEREFORE NO LONGER IN
EFFECT.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR PAZ061-062-103>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
NJ...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR NJZ001-007>010-
012>015-019-020-025>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>452.
SMALL CRAFT ADVISORY UNTIL 6 AM EST WEDNESDAY FOR ANZ430-431-
453>455.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC/DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/KLINE/O`HARA
MARINE...AMC/DRAG/O`HARA
HYDROLOGY...
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
133 PM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE MID-MORNING UPDATE...THE FORECAST FROM EARLIER THIS
MORNING IS BASICALLY ON TRACK BUT HAVE MADE ADJUSTMENTS TO SOME
OF THE HAZARDS. AS OF 900 AM TEMPS ACROSS ALL THE FCST AREA SEEM
TO HAVE RISEN ABOVE FREEZING AND ALL REPORTED PRECIP IS RAIN...SO
THE WINTER WEATHER ADVISORY FOR PARTS OF NW NJ AND ERN PA HAS BEEN
CANCELLED. TEMPS SHOULD CONTINUE TO RISE A COUPLE MORE DEGREES
TODAY. THE WINTER STORM WARNING FOR CARBON AND MONROE COUNTIES
REMAINS IN EFFECT FOR EXPECTED SNOW LATER TONIGHT AND ON
WEDNESDAY.
MEANWHILE...RADAR SHOWS THE AREA OF HEAVIEST RAIN NOW WRAPPING
WWD ACROSS NRN NJ AND INTO ERN PA. THIS AXIS SHOULD CONTINUE TO
SHIFT NWD ALONG WITH THE LOW-LVL STORM CENTER AND BEST EASTERLY
INFLOW. THE FLOOD WATCH AREA HAS BEEN ADJUSTED TO REMOVE AREAS
FROM PHL SWWD...AND ALSO ADD THE TIER OF COUNTIES OVER FAR NW NJ
AND ADJ ERN PA.
PREVIOUS DISCUSSION BELOW...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO CHANGE
TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS THAN
FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
LATE DAY AND TONIGHT...LOW-END MVFR TO IFR CONDITIONS AT TIMES WITH
AREAS OF LIGHT RAIN AND/OR SHOWERS. GUSTY NORTH-NORTHWEST WINDS TO
BETWEEN 20 TO 30 KT ARE EXPECTED THROUGH LATE-DAY, BEFORE WINDS BACK
A LITTLE MORE TO THE NORTHWEST AND GUSTS DECREASE SOMEWHAT TO MORE
IN THE 18 TO 24 KNOT RANGE FOR LATE EVENING AND OVERNIGHT. WITH THE
STORM SYSTEM ONLY SLOWLY MOVING AWAY OVERNIGHT, MORE WRAP-AROUND
MOISTURE WILL YIELD SOME BANDS OF RAIN SHIFTING SOUTHEASTWARD ACROSS
THE REGION, WITH RAIN CHANGING TO WET SNOW, ESPECIALLY AT KRDG AND
KABE DURING THE EARLY MORNING HOURS WEDNESDAY. WE ALSO HAVE MEDIUM
CONFIDENCE ON A RAIN/SNOW MIX AND A WINDOW OF A FEW HOURS OF
POSSIBLE WET SNOW TOWARD THE DELAWARE VALLEY TAF SITES, INCLUDING
KPHL, INTO WEDNESDAY MORNING.
WEDNESDAY...CONTINUED RESTRICTIONS IN THE MVFR TO POSSIBLY IFR RANGE
WITH SOME BANDS OF RAIN AND SNOW SHOWERS. GUSTY NORTHWEST WINDS WILL
CONTINUE, WITH GUSTS INCREASING DURING THE DAYTIME, MORE IN THE 23
TO 30 KNOT RANGE.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR
IFR IN BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30
KNOTS AT TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING HAS BEEN CONVERTED TO SMALL CRAFT ADVISORY FOR
COASTAL WATERS SOUTH OF GREAT EGG INLET AND FOR LOWER DELAWARE
BAY. THE GALE WARNING CONTINUES NORTH OF GREAT EGG IN TIGHTER PRES
GRADIENT AHEAD OF DEEPENING SFC LOW AND GALE FORCE NE WINDS. THE
SCA WAS EXTENDED OVERNIGHT AND WILL LIKELY NEED FURTHER EXTENSION
INTO WED FOR ALL WATERS...AS THE SFC LOW IS FCST TO STALL INVOF
LONG ISLAND. WINDS WILL BECOME OFFSHORE OR MORE OFFSHORE RESULTING
IN SMWHT LOWER SEAS WITH THE MORE LIMITED FETCH.
PREVIOUS DISCUSSION BELOW...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
THE FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR FROM PHILLY NORTH.
THE SOUTHERN PORTION OF THE WATCH HAS BEEN CANCELLED WITH THE BULK
OF THE MODERATE TO HEAVY RAIN PUSHING NORTH. FOUR COUNTIES HAVE BEEN
ADDED OF THE NORTHWEST PERIPHERY, LEHIGH NORTHEAST THROUGH SUSSEX AS
THE PRECIPITATION HAS BECOME LIQUID.
THE HEAVIER RAINS WILL CONTINUE INTO THE MID TO LATE AFTERNOON
HOURS BEFORE ENDING. RUNOFF WILL CONTINUE THROUGH THE OVERNIGHT,
LONGER IN SOME SPOTS. ANTECEDENT CONDITIONS ARE WET DUE TO THE
RAINS THE REGION SAW THIS PAST SATURDAY. THIS IS ALLOWING FOR A
MORE EFFICIENT RUNOFF.
WHERE IT RAINS THE HEAVIEST, TOTAL RAINFALL ACCUMULATIONS WILL BE IN
THE 2 TO 3 INCH RANGE. THERE COULD BE SOME TOTALS OVER 3 INCHES.
SMALLER CREEKS AND STREAMS WILL BE THE FIRST BODIES OF WATER TO
RESPOND. THEY ALREADY HAVE. THOSE AREAS WHICH DRAIN INTO TIDAL
WATERS COULD SEE INCREASED FLOODING (IN THE MINOR CATEGORY) DUE TO
HIGHER THAN NORMAL TIDES.
ON THE LARGER BODIES OF WATER THAT ARE SUPPORTED BY THE MARFC, THERE
ARE ABOUT A DOZEN FORECAST POINTS THAT EXCEED CAUTION/ACTION STAGE,
A FEW OF THEM LASTING THROUGH THE NEXT FEW DAYS. THE MAJORITY OF
THESE POINT ARE IN NJ.
AS FOR GAUGES HITTING FLOOD STAGE, WE WILL KEEP AN EYE ON BLACKWELLS
MILLS AND PEMBERTON. IF RUNOFF AND RISES CONTINUE AS EXPECTED INTO
THIS AFTERNOON, FLOOD WARNINGS WILL BE ISSUED LATER TODAY. PEMBERTON
COULD HIT FLOOD STAGE AS EARLY AS THIS EVENING AND BLACKWELLS MILLS
COULD HIT FLOOD STAGE OVERNIGHT TONIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
WATER BUILDUP HAS OCCURRED IN ALL OUR TIDAL WATERS DURING THE PAST
SEVERAL TIDE CYCLES, INCLUDING THE DELAWARE AND CHESAPEAKE BAYS AND
THE DELAWARE RIVER. ANOMALIES THIS MORNING ARE RUNNING BETWEEN 2 AND
2.5 FEET ABOVE NORMAL NORTH OF ATLANTIC CITY, AND 2.5 TO 3 FEET
ABOVE NORMAL SOUTH OF ATLANTIC CITY. IN THE DELAWARE BAY, ANOMALIES
ARE AROUND 2.5 FEET ABOVE NORMAL, AND IN THE CHESAPEAKE BAY 1 FOOT
ABOVE NORMAL. A STRONG ONSHORE FLOW SHOULD MAINTAIN THESE ANOMALIES
THROUGH THE HIGH TIDE CYCLE THIS MORNING AND EARLY AFTERNOON. THEN,
AS THE COASTAL LOW CONTINUES TO MOVE SLOWLY NORTH, WINDS WILL
GRADUALLY SHIFT TO THE NORTH, THEN NORTHWEST, WHICH SHOULD EAT AWAY
AT THESE ANOMALIES, PARTICULARLY SOUTH OF ATLANTIC CITY. LOWER ANOMALIES
COMBINED WITH A SMALLER ASTRONOMICAL CONTRIBUTION (0.5 TO 1.0 FOOT
LOWER) SHOULD KEEP ANY ADDITIONAL TIDAL FLOODING DURING THE NEXT
HIGH TIDE CYCLE TONIGHT IN THE MINOR RANGE FROM ATLANTIC CITY SOUTH.
SO...MODERATE FLOODING EXPECTED ALONG THE COAST AND ASSOCIATED
BACKBAYS WITH THIS MORNINGS HIGH TIDE, MODERATE FLOODING EXPECTED
ALONG THE SHORES OF THE LOWER DELAWARE BAY, AND MINOR TO LOW END
MODERATE FLOODING EXPECTED ON THE UPPER DELAWARE BAY. MINOR TIDAL
FLOODING IS A POSSIBILITY ON THE TIDAL DELAWARE (NORTH OF REEDY
POINT, INCLUDING PHILADELPHIA), AND AN ADVISORY MAY BE NEEDED.
ELEVATED WATER LEVELS ARE OCCURRING IN THE NORTHERN PORTIONS OF THE
CHESAPEAKE BAY, BUT NO FLOODING IS EXPECTED. AS ALWAYS, ROUGH SURF
AND HEAVY RAIN AT THE TIME OF HIGH TIDE WILL EXACERBATE THE FLOODING
ISSUE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR PAZ061-062-103>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
NJ...FLOOD WATCH UNTIL 1 AM EST WEDNESDAY FOR NJZ001-007>010-
012>015-019-020-025>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>452.
SMALL CRAFT ADVISORY UNTIL 6 AM EST WEDNESDAY FOR ANZ430-431-
453>455.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC/DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/KLINE/O`HARA
MARINE...AMC/DRAG/O`HARA
HYDROLOGY...KRUZDLO
TIDES/COASTAL FLOODING...MIKETTA
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1255 PM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE MID-MORNING UPDATE...THE FORECAST FROM EARLIER THIS
MORNING IS BASICALLY ON TRACK BUT HAVE MADE ADJUSTMENTS TO SOME
OF THE HAZARDS. AS OF 900 AM TEMPS ACROSS ALL THE FCST AREA SEEM
TO HAVE RISEN ABOVE FREEZING AND ALL REPORTED PRECIP IS RAIN...SO
THE WINTER WEATHER ADVISORY FOR PARTS OF NW NJ AND ERN PA HAS BEEN
CANCELLED. TEMPS SHOULD CONTINUE TO RISE A COUPLE MORE DEGREES
TODAY. THE WINTER STORM WARNING FOR CARBON AND MONROE COUNTIES
REMAINS IN EFFECT FOR EXPECTED SNOW LATER TONIGHT AND ON
WEDNESDAY.
MEANWHILE...RADAR SHOWS THE AREA OF HEAVIEST RAIN NOW WRAPPING
WWD ACROSS NRN NJ AND INTO ERN PA. THIS AXIS SHOULD CONTINUE TO
SHIFT NWD ALONG WITH THE LOW-LVL STORM CENTER AND BEST EASTERLY
INFLOW. THE FLOOD WATCH AREA HAS BEEN ADJUSTED TO REMOVE AREAS
FROM PHL SWWD...AND ALSO ADD THE TIER OF COUNTIES OVER FAR NW NJ
AND ADJ ERN PA.
PREVIOUS DISCUSSION BELOW...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO CHANGE
TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS THAN
FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR TO POSSIBLY LOW-END MVFR IN RAIN OR DRIZZLE, AS MOST OF
THE STEADIER MODERATE RAIN WILL CONTINUE LIFTING NORTH OF THE TAF
SITES THROUGH THE REST OF THIS MORNING. GUSTY NORTH WINDS TO BETWEEN
20 TO 30 KT ARE EXPECTED, EXCEPT AROUND 35 KT AT TIMES IN VICINITY
OF KACY. CONDITIONS SHOULD IMPROVE THIS AFTERNOON AS THE STEADIER
RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE NORTH NORTHWEST. GUSTS
DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING HAS BEEN CONVERTED TO SMALL CRAFT ADVISORY FOR
COASTAL WATERS SOUTH OF GREAT EGG INLET AND FOR LOWER DELAWARE
BAY. THE GALE WARNING CONTINUES NORTH OF GREAT EGG IN TIGHTER PRES
GRADIENT AHEAD OF DEEPENING SFC LOW AND GALE FORCE NE WINDS. THE
SCA WAS EXTENDED OVERNIGHT AND WILL LIKELY NEED FURTHER EXTENSION
INTO WED FOR ALL WATERS...AS THE SFC LOW IS FCST TO STALL INVOF
LONG ISLAND. WINDS WILL BECOME OFFSHORE OR MORE OFFSHORE RESULTING
IN SMWHT LOWER SEAS WITH THE MORE LIMITED FETCH.
PREVIOUS DISCUSSION BELOW...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
THE FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR FROM PHILLY NORTH.
THE SOUTHERN PORTION OF THE WATCH HAS BEEN CANCELLED WITH THE BULK
OF THE MODERATE TO HEAVY RAIN PUSHING NORTH. FOUR COUNTIES HAVE BEEN
ADDED OF THE NORTHWEST PERIPHERY, LEHIGH NORTHEAST THROUGH SUSSEX AS
THE PRECIPITATION HAS BECOME LIQUID.
THE HEAVIER RAINS WILL CONTINUE INTO THE MID TO LATE AFTERNOON
HOURS BEFORE ENDING. RUNOFF WILL CONTINUE THROUGH THE OVERNIGHT,
LONGER IN SOME SPOTS. ANTECEDENT CONDITIONS ARE WET DUE TO THE
RAINS THE REGION SAW THIS PAST SATURDAY. THIS IS ALLOWING FOR A
MORE EFFICIENT RUNOFF.
WHERE IT RAINS THE HEAVIEST, TOTAL RAINFALL ACCUMULATIONS WILL BE IN
THE 2 TO 3 INCH RANGE. THERE COULD BE SOME TOTALS OVER 3 INCHES.
SMALLER CREEKS AND STREAMS WILL BE THE FIRST BODIES OF WATER TO
RESPOND. THEY ALREADY HAVE. THOSE AREAS WHICH DRAIN INTO TIDAL
WATERS COULD SEE INCREASED FLOODING (IN THE MINOR CATEGORY) DUE TO
HIGHER THAN NORMAL TIDES.
ON THE LARGER BODIES OF WATER THAT ARE SUPPORTED BY THE MARFC, THERE
ARE ABOUT A DOZEN FORECAST POINTS THAT EXCEED CAUTION/ACTION STAGE,
A FEW OF THEM LASTING THROUGH THE NEXT FEW DAYS. THE MAJORITY OF
THESE POINT ARE IN NJ.
AS FOR GAUGES HITTING FLOOD STAGE, WE WILL KEEP AN EYE ON BLACKWELLS
MILLS AND PEMBERTON. IF RUNOFF AND RISES CONTINUE AS EXPECTED INTO
THIS AFTERNOON, FLOOD WARNINGS WILL BE ISSUED LATER TODAY. PEMBERTON
COULD HIT FLOOD STAGE AS EARLY AS THIS EVENING AND BLACKWELLS MILLS
COULD HIT FLOOD STAGE OVERNIGHT TONIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
WATER BUILDUP HAS OCCURRED IN ALL OUR TIDAL WATERS DURING THE PAST
SEVERAL TIDE CYCLES, INCLUDING THE DELAWARE AND CHESAPEAKE BAYS AND
THE DELAWARE RIVER. ANOMALIES THIS MORNING ARE RUNNING BETWEEN 2 AND
2.5 FEET ABOVE NORMAL NORTH OF ATLANTIC CITY, AND 2.5 TO 3 FEET
ABOVE NORMAL SOUTH OF ATLANTIC CITY. IN THE DELAWARE BAY, ANOMALIES
ARE AROUND 2.5 FEET ABOVE NORMAL, AND IN THE CHESAPEAKE BAY 1 FOOT
ABOVE NORMAL. A STRONG ONSHORE FLOW SHOULD MAINTAIN THESE ANOMALIES
THROUGH THE HIGH TIDE CYCLE THIS MORNING AND EARLY AFTERNOON. THEN,
AS THE COASTAL LOW CONTINUES TO MOVE SLOWLY NORTH, WINDS WILL
GRADUALLY SHIFT TO THE NORTH, THEN NORTHWEST, WHICH SHOULD EAT AWAY
AT THESE ANOMALIES, PARTICULARLY SOUTH OF ATLANTIC CITY. LOWER ANOMALIES
COMBINED WITH A SMALLER ASTRONOMICAL CONTRIBUTION (0.5 TO 1.0 FOOT
LOWER) SHOULD KEEP ANY ADDITIONAL TIDAL FLOODING DURING THE NEXT
HIGH TIDE CYCLE TONIGHT IN THE MINOR RANGE FROM ATLANTIC CITY SOUTH.
SO...MODERATE FLOODING EXPECTED ALONG THE COAST AND ASSOCIATED
BACKBAYS WITH THIS MORNINGS HIGH TIDE, MODERATE FLOODING EXPECTED
ALONG THE SHORES OF THE LOWER DELAWARE BAY, AND MINOR TO LOW END
MODERATE FLOODING EXPECTED ON THE UPPER DELAWARE BAY. MINOR TIDAL
FLOODING IS A POSSIBILITY ON THE TIDAL DELAWARE (NORTH OF REEDY
POINT, INCLUDING PHILADELPHIA), AND AN ADVISORY MAY BE NEEDED.
ELEVATED WATER LEVELS ARE OCCURRING IN THE NORTHERN PORTIONS OF THE
CHESAPEAKE BAY, BUT NO FLOODING IS EXPECTED. AS ALWAYS, ROUGH SURF
AND HEAVY RAIN AT THE TIME OF HIGH TIDE WILL EXACERBATE THE FLOODING
ISSUE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ061-062-103>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ001-007>010-012>015-
019-020-025>027.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NJZ016.
DE...COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
DEZ001.
MD...NONE.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>452.
SMALL CRAFT ADVISORY UNTIL 6 AM EST WEDNESDAY FOR ANZ430-431-
453>455.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC/DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/KLINE/O`HARA
MARINE...AMC/DRAG/O`HARA
HYDROLOGY...
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1026 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE MID-MORNING UPDATE...THE FORECAST FROM EARLIER THIS
MORNING IS BASICALLY ON TRACK BUT HAVE MADE ADJUSTMENTS TO SOME
OF THE HAZARDS. AS OF 900 AM TEMPS ACROSS ALL THE FCST AREA SEEM
TO HAVE RISEN ABOVE FREEZING AND ALL REPORTED PRECIP IS RAIN...SO
THE WINTER WEATHER ADVISORY FOR PARTS OF NW NJ AND ERN PA HAS BEEN
CANCELLED. TEMPS SHOULD CONTINUE TO RISE A COUPLE MORE DEGREES
TODAY. THE WINTER STORM WARNING FOR CARBON AND MONROE COUNTIES
REMAINS IN EFFECT FOR EXPECTED SNOW LATER TONIGHT AND ON
WEDNESDAY.
MEANWHILE...RADAR SHOWS THE AREA OF HEAVIEST RAIN NOW WRAPPING
WWD ACROSS NRN NJ AND INTO ERN PA. THIS AXIS SHOULD CONTINUE TO
SHIFT NWD ALONG WITH THE LOW-LVL STORM CENTER AND BEST EASTERLY
INFLOW. THE FLOOD WATCH AREA HAS BEEN ADJUSTED TO REMOVE AREAS
FROM PHL SWWD...AND ALSO ADD THE TIER OF COUNTIES OVER FAR NW NJ
AND ADJ ERN PA.
PREVIOUS DISCUSSION BELOW...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO CHANGE
TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS THAN
FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR TO POSSIBLY LOW-END MVFR IN RAIN OR DRIZZLE, AS MOST OF
THE STEADIER MODERATE RAIN WILL CONTINUE LIFTING NORTH OF THE TAF
SITES THROUGH THE REST OF THIS MORNING. GUSTY NORTH WINDS TO BETWEEN
20 TO 30 KT ARE EXPECTED, EXCEPT AROUND 35 KT AT TIMES IN VICINITY
OF KACY. CONDITIONS SHOULD IMPROVE THIS AFTERNOON AS THE STEADIER
RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE NORTH NORTHWEST. GUSTS
DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
THE FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR FROM PHILLY NORTH.
THE SOUTHERN PORTION OF THE WATCH HAS BEEN CANCELLED WITH THE BULK
OF THE MODERATE TO HEAVY RAIN PUSHING NORTH. FOUR COUNTIES HAVE BEEN
ADDED OF THE NORTHWEST PERIPHERY, LEHIGH NORTHEAST THROUGH SUSSEX AS
THE PRECIPITATION HAS BECOME LIQUID.
THE HEAVIER RAINS WILL CONTINUE INTO THE MID TO LATE AFTERNOON
HOURS BEFORE ENDING. RUNOFF WILL CONTINUE THROUGH THE OVERNIGHT,
LONGER IN SOME SPOTS. ANTECEDENT CONDITIONS ARE WET DUE TO THE
RAINS THE REGION SAW THIS PAST SATURDAY. THIS IS ALLOWING FOR A
MORE EFFICIENT RUNOFF.
WHERE IT RAINS THE HEAVIEST, TOTAL RAINFALL ACCUMULATIONS WILL BE IN
THE 2 TO 3 INCH RANGE. THERE COULD BE SOME TOTALS OVER 3 INCHES.
SMALLER CREEKS AND STREAMS WILL BE THE FIRST BODIES OF WATER TO
RESPOND. THEY ALREADY HAVE. THOSE AREAS WHICH DRAIN INTO TIDAL
WATERS COULD SEE INCREASED FLOODING (IN THE MINOR CATEGORY) DUE TO
HIGHER THAN NORMAL TIDES.
ON THE LARGER BODIES OF WATER THAT ARE SUPPORTED BY THE MARFC, THERE
ARE ABOUT A DOZEN FORECAST POINTS THAT EXCEED CAUTION/ACTION STAGE,
A FEW OF THEM LASTING THROUGH THE NEXT FEW DAYS. THE MAJORITY OF
THESE POINT ARE IN NJ.
AS FOR GAUGES HITTING FLOOD STAGE, WE WILL KEEP AN EYE ON BLACKWELLS
MILLS AND PEMBERTON. IF RUNOFF AND RISES CONTINUE AS EXPECTED INTO
THIS AFTERNOON, FLOOD WARNINGS WILL BE ISSUED LATER TODAY. PEMBERTON
COULD HIT FLOOD STAGE AS EARLY AS THIS EVENING AND BLACKWELLS MILLS
COULD HIT FLOOD STAGE OVERNIGHT TONIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
WATER BUILDUP HAS OCCURRED IN ALL OUR TIDAL WATERS DURING THE PAST
SEVERAL TIDE CYCLES, INCLUDING THE DELAWARE AND CHESAPEAKE BAYS AND
THE DELAWARE RIVER. ANOMALIES THIS MORNING ARE RUNNING BETWEEN 2 AND
2.5 FEET ABOVE NORMAL NORTH OF ATLANTIC CITY, AND 2.5 TO 3 FEET
ABOVE NORMAL SOUTH OF ATLANTIC CITY. IN THE DELAWARE BAY, ANOMALIES
ARE AROUND 2.5 FEET ABOVE NORMAL, AND IN THE CHESAPEAKE BAY 1 FOOT
ABOVE NORMAL. A STRONG ONSHORE FLOW SHOULD MAINTAIN THESE ANOMALIES
THROUGH THE HIGH TIDE CYCLE THIS MORNING AND EARLY AFTERNOON. THEN,
AS THE COASTAL LOW CONTINUES TO MOVE SLOWLY NORTH, WINDS WILL
GRADUALLY SHIFT TO THE NORTH, THEN NORTHWEST, WHICH SHOULD EAT AWAY
AT THESE ANOMALIES, PARTICULARLY SOUTH OF ATLANTIC CITY. LOWER ANOMALIES
COMBINED WITH A SMALLER ASTRONOMICAL CONTRIBUTION (0.5 TO 1.0 FOOT
LOWER) SHOULD KEEP ANY ADDITIONAL TIDAL FLOODING DURING THE NEXT
HIGH TIDE CYCLE TONIGHT IN THE MINOR RANGE FROM ATLANTIC CITY SOUTH.
SO...MODERATE FLOODING EXPECTED ALONG THE COAST AND ASSOCIATED
BACKBAYS WITH THIS MORNINGS HIGH TIDE, MODERATE FLOODING EXPECTED
ALONG THE SHORES OF THE LOWER DELAWARE BAY, AND MINOR TO LOW END
MODERATE FLOODING EXPECTED ON THE UPPER DELAWARE BAY. MINOR TIDAL
FLOODING IS A POSSIBILITY ON THE TIDAL DELAWARE (NORTH OF REEDY
POINT, INCLUDING PHILADELPHIA), AND AN ADVISORY MAY BE NEEDED.
ELEVATED WATER LEVELS ARE OCCURRING IN THE NORTHERN PORTIONS OF THE
CHESAPEAKE BAY, BUT NO FLOODING IS EXPECTED. AS ALWAYS, ROUGH SURF
AND HEAVY RAIN AT THE TIME OF HIGH TIDE WILL EXACERBATE THE FLOODING
ISSUE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ061-062-103>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ001-007>010-012>015-
019-020-025>027.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NJZ016.
DE...COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
DEZ001.
MD...NONE.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC/DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/KLINE/O`HARA
MARINE...DRAG/O`HARA
HYDROLOGY...KRUZDLO
TIDES/COASTAL FLOODING...MIKETTA
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
954 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE MID-MORNING UPDATE...THE FORECAST FROM EARLIER THIS
MORNING IS BASICALLY ON TRACK BUT HAVE MADE ADJUSTMENTS TO SOME
OF THE HAZARDS. AS OF 900 AM TEMPS ACROSS ALL THE FCST AREA SEEM
TO HAVE RISEN ABOVE FREEZING AND ALL REPORTED PRECIP IS RAIN...SO
THE WINTER WEATHER ADVISORY FOR PARTS OF NW NJ AND ERN PA HAS BEEN
CANCELLED. TEMPS SHOULD CONTINUE TO RISE A COUPLE MORE DEGREES
TODAY. THE WINTER STORM WARNING FOR CARBON AND MONROE COUNTIES
REMAINS IN EFFECT FOR EXPECTED SNOW LATER TONIGHT AND ON
WEDNESDAY.
MEANWHILE...RADAR SHOWS THE AREA OF HEAVIEST RAIN NOW WRAPPING
WWD ACROSS NRN NJ AND INTO ERN PA. THIS AXIS SHOULD CONTINUE TO
SHIFT NWD ALONG WITH THE LOW-LVL STORM CENTER AND BEST EASTERLY
INFLOW. THE FLOOD WATCH AREA HAS BEEN ADJUSTED TO REMOVE AREAS
FROM PHL SWWD...AND ALSO ADD THE TIER OF COUNTIES OVER FAR NW NJ
AND ADJ ERN PA.
PREVIOUS DISCUSSION BELOW...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO CHANGE
TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS THAN
FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR TO POSSIBLY LOW-END MVFR IN RAIN OR DRIZZLE, AS MOST OF
THE STEADIER MODERATE RAIN WILL CONTINUE LIFTING NORTH OF THE TAF
SITES THROUGH THE REST OF THIS MORNING. GUSTY NORTH WINDS TO BETWEEN
20 TO 30 KT ARE EXPECTED, EXCEPT AROUND 35 KT AT TIMES IN VICINITY
OF KACY. CONDITIONS SHOULD IMPROVE THIS AFTERNOON AS THE STEADIER
RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE NORTH NORTHWEST. GUSTS
DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR ZONES INCLUDING PARTS
OF SOUTHERN NEW JERSEY WHERE 1.5 TO POSSIBLY 3 INCHES OF RAIN IS
EXPECTED TO FALL THROUGH THIS EVENING. THE RAIN, HEAVY AT TIMES,
WILL ADD TO THE ALREADY WET ANTECEDENT CONDITIONS ACROSS THE
REGION. THIS WILL ALLOW FOR BETTER RUNOFF INTO AREAS STREAMS AND
CREEKS AND SOME OF THE SMALLER RIVERS...THE MAINSTEM RIVERS SHOULD
REMAIN WITHIN THEIR BANKS.
HEAVIEST APPEARS TO BE NNJ AND COASTAL NJ.
SO FAR AS OF 530 AM: MANY REPORTS 1 TO 1.9 INCHES IN CAPE MAY...BURLINGTON
AND ATLANTIC COUNTIES SINCE THE RAIN BEGAN AROUND MIDNIGHT.
THE MAIN AREA OF DOUBT IS THE SW END OF THE WATCH IN NORTHERN DE WHERE
RAINFALL LOOKS TO BE LESS THAN 1.5 INCHES. I COULD SEE THIS PART
OF THE WATCH BEING CANCELLED LATER THIS MORNING.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
WATER BUILDUP HAS OCCURRED IN ALL OUR TIDAL WATERS DURING THE PAST
SEVERAL TIDE CYCLES, INCLUDING THE DELAWARE AND CHESAPEAKE BAYS AND
THE DELAWARE RIVER. ANOMALIES THIS MORNING ARE RUNNING BETWEEN 2 AND
2.5 FEET ABOVE NORMAL NORTH OF ATLANTIC CITY, AND 2.5 TO 3 FEET
ABOVE NORMAL SOUTH OF ATLANTIC CITY. IN THE DELAWARE BAY, ANOMALIES
ARE AROUND 2.5 FEET ABOVE NORMAL, AND IN THE CHESAPEAKE BAY 1 FOOT
ABOVE NORMAL. A STRONG ONSHORE FLOW SHOULD MAINTAIN THESE ANOMALIES
THROUGH THE HIGH TIDE CYCLE THIS MORNING AND EARLY AFTERNOON. THEN,
AS THE COASTAL LOW CONTINUES TO MOVE SLOWLY NORTH, WINDS WILL
GRADUALLY SHIFT TO THE NORTH, THEN NORTHWEST, WHICH SHOULD EAT AWAY
AT THESE ANOMALIES, PARTICULARLY SOUTH OF ATLANTIC CITY. LOWER ANOMALIES
COMBINED WITH A SMALLER ASTRONOMICAL CONTRIBUTION (0.5 TO 1.0 FOOT
LOWER) SHOULD KEEP ANY ADDITIONAL TIDAL FLOODING DURING THE NEXT
HIGH TIDE CYCLE TONIGHT IN THE MINOR RANGE FROM ATLANTIC CITY SOUTH.
SO...MODERATE FLOODING EXPECTED ALONG THE COAST AND ASSOCIATED
BACKBAYS WITH THIS MORNINGS HIGH TIDE, MODERATE FLOODING EXPECTED
ALONG THE SHORES OF THE LOWER DELAWARE BAY, AND MINOR TO LOW END
MODERATE FLOODING EXPECTED ON THE UPPER DELAWARE BAY. MINOR TIDAL
FLOODING IS A POSSIBILITY ON THE TIDAL DELAWARE (NORTH OF REEDY
POINT, INCLUDING PHILADELPHIA), AND AN ADVISORY MAY BE NEEDED.
ELEVATED WATER LEVELS ARE OCCURRING IN THE NORTHERN PORTIONS OF THE
CHESAPEAKE BAY, BUT NO FLOODING IS EXPECTED. AS ALWAYS, ROUGH SURF
AND HEAVY RAIN AT THE TIME OF HIGH TIDE WILL EXACERBATE THE FLOODING
ISSUE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ061-062-103>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ001-007>010-012>015-
019-020-025>027.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NJZ016.
DE...COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
DEZ001.
MD...NONE.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC/DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/KLINE/O`HARA
MARINE...DRAG/O`HARA
HYDROLOGY...DRAG
TIDES/COASTAL FLOODING...MIKETTA
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
947 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE MID-MORNING UPDATE...THE FORECAST FROM EARLIER THIS
MORNING IS BASICALLY ON TRACK BUT HAVE MADE ADJUSTMENTS TO SOME
OF THE HAZARDS. AS OF 900 AM TEMPS ACROSS ALL THE FCST AREA SEEM
TO HAVE RISEN ABOVE FREEZING AND ALL REPORTED PRECIP IS RAIN...SO
THE WINTER WEATHER ADVISORY FOR PARTS OF NW NJ AND ERN PA HAS BEEN
CANCELLED. TEMPS SHOULD CONTINUE TO RISE A COUPLE MORE DEGREES
TODAY. THE WINTER STORM WARNING FOR CARBON AND MONROE COUNTIES
REMAINS IN EFFECT FOR EXPECTED SNOW LATER TONIGHT AND ON
WEDNESDAY.
MEANWHILE...RADAR SHOWS THE AREA OF HEAVIEST RAIN NOW WRAPPING
WWD ACROSS NRN NJ AND INTO ERN PA. THIS AXIS SHOULD CONTINUE TO
SHIFT NWD ALONG WITH THE LOW-LVL STORM CENTER AND BEST EASTERLY
INFLOW. THE FLOOD WATCH AREA HAS BEEN ADJUSTED TO REMOVE AREAS
FROM PHL SWWD...AND ALSO ADD THE TIER OF COUNTIES OVER FAR NW NJ
AND ADJ ERN PA.
PREVIOUS DISCUSSION BELOW...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO CHANGE
TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS THAN
FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR IN RAIN..SOME HEAVY WITH FREEZING RAIN AT KRDG AND
KABE FOR A LITTLE WHILE THIS MORNING. GUSTY NORTH WINDS TO 2O TO
30 KT EXCEPT NEAR 40 KT VCNTY KACY. CONDITIONS SHOULD IMPROVE THIS
AFTERNOON AS HEAVY RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE
NORTH NORTHWEST. GUSTS DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR ZONES INCLUDING PARTS
OF SOUTHERN NEW JERSEY WHERE 1.5 TO POSSIBLY 3 INCHES OF RAIN IS
EXPECTED TO FALL THROUGH THIS EVENING. THE RAIN, HEAVY AT TIMES,
WILL ADD TO THE ALREADY WET ANTECEDENT CONDITIONS ACROSS THE
REGION. THIS WILL ALLOW FOR BETTER RUNOFF INTO AREAS STREAMS AND
CREEKS AND SOME OF THE SMALLER RIVERS...THE MAINSTEM RIVERS SHOULD
REMAIN WITHIN THEIR BANKS.
HEAVIEST APPEARS TO BE NNJ AND COASTAL NJ.
SO FAR AS OF 530 AM: MANY REPORTS 1 TO 1.9 INCHES IN CAPE MAY...BURLINGTON
AND ATLANTIC COUNTIES SINCE THE RAIN BEGAN AROUND MIDNIGHT.
THE MAIN AREA OF DOUBT IS THE SW END OF THE WATCH IN NORTHERN DE WHERE
RAINFALL LOOKS TO BE LESS THAN 1.5 INCHES. I COULD SEE THIS PART
OF THE WATCH BEING CANCELLED LATER THIS MORNING.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
WATER BUILDUP HAS OCCURRED IN ALL OUR TIDAL WATERS DURING THE PAST
SEVERAL TIDE CYCLES, INCLUDING THE DELAWARE AND CHESAPEAKE BAYS AND
THE DELAWARE RIVER. ANOMALIES THIS MORNING ARE RUNNING BETWEEN 2 AND
2.5 FEET ABOVE NORMAL NORTH OF ATLANTIC CITY, AND 2.5 TO 3 FEET
ABOVE NORMAL SOUTH OF ATLANTIC CITY. IN THE DELAWARE BAY, ANOMALIES
ARE AROUND 2.5 FEET ABOVE NORMAL, AND IN THE CHESAPEAKE BAY 1 FOOT
ABOVE NORMAL. A STRONG ONSHORE FLOW SHOULD MAINTAIN THESE ANOMALIES
THROUGH THE HIGH TIDE CYCLE THIS MORNING AND EARLY AFTERNOON. THEN,
AS THE COASTAL LOW CONTINUES TO MOVE SLOWLY NORTH, WINDS WILL
GRADUALLY SHIFT TO THE NORTH, THEN NORTHWEST, WHICH SHOULD EAT AWAY
AT THESE ANOMALIES, PARTICULARLY SOUTH OF ATLANTIC CITY. LOWER ANOMALIES
COMBINED WITH A SMALLER ASTRONOMICAL CONTRIBUTION (0.5 TO 1.0 FOOT
LOWER) SHOULD KEEP ANY ADDITIONAL TIDAL FLOODING DURING THE NEXT
HIGH TIDE CYCLE TONIGHT IN THE MINOR RANGE FROM ATLANTIC CITY SOUTH.
SO...MODERATE FLOODING EXPECTED ALONG THE COAST AND ASSOCIATED
BACKBAYS WITH THIS MORNINGS HIGH TIDE, MODERATE FLOODING EXPECTED
ALONG THE SHORES OF THE LOWER DELAWARE BAY, AND MINOR TO LOW END
MODERATE FLOODING EXPECTED ON THE UPPER DELAWARE BAY. MINOR TIDAL
FLOODING IS A POSSIBILITY ON THE TIDAL DELAWARE (NORTH OF REEDY
POINT, INCLUDING PHILADELPHIA), AND AN ADVISORY MAY BE NEEDED.
ELEVATED WATER LEVELS ARE OCCURRING IN THE NORTHERN PORTIONS OF THE
CHESAPEAKE BAY, BUT NO FLOODING IS EXPECTED. AS ALWAYS, ROUGH SURF
AND HEAVY RAIN AT THE TIME OF HIGH TIDE WILL EXACERBATE THE FLOODING
ISSUE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ061-062-103>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ001-007>010-012>015-
019-020-025>027.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NJZ016.
DE...COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
DEZ001.
MD...NONE.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC/DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/O`HARA
MARINE...DRAG/O`HARA
HYDROLOGY...DRAG
TIDES/COASTAL FLOODING...MIKETTA
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
847 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WARNING: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO CHANGE
TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS THAN
FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR IN RAIN..SOME HEAVY WITH FREEZING RAIN AT KRDG AND
KABE FOR A LITTLE WHILE THIS MORNING. GUSTY NORTH WINDS TO 2O TO
30 KT EXCEPT NEAR 40 KT VCNTY KACY. CONDITIONS SHOULD IMPROVE THIS
AFTERNOON AS HEAVY RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE
NORTH NORTHWEST. GUSTS DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR ZONES INCLUDING PARTS
OF SOUTHERN NEW JERSEY WHERE 1.5 TO POSSIBLY 3 INCHES OF RAIN IS
EXPECTED TO FALL THROUGH THIS EVENING. THE RAIN, HEAVY AT TIMES,
WILL ADD TO THE ALREADY WET ANTECEDENT CONDITIONS ACROSS THE
REGION. THIS WILL ALLOW FOR BETTER RUNOFF INTO AREAS STREAMS AND
CREEKS AND SOME OF THE SMALLER RIVERS...THE MAINSTEM RIVERS SHOULD
REMAIN WITHIN THEIR BANKS.
HEAVIEST APPEARS TO BE NNJ AND COASTAL NJ.
SO FAR AS OF 530 AM: MANY REPORTS 1 TO 1.9 INCHES IN CAPE MAY...BURLINGTON
AND ATLANTIC COUNTIES SINCE THE RAIN BEGAN AROUND MIDNIGHT.
THE MAIN AREA OF DOUBT IS THE SW END OF THE WATCH IN NORTHERN DE WHERE
RAINFALL LOOKS TO BE LESS THAN 1.5 INCHES. I COULD SEE THIS PART
OF THE WATCH BEING CANCELLED LATER THIS MORNING.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
WATER BUILDUP HAS OCCURRED IN ALL OUR TIDAL WATERS DURING THE PAST
SEVERAL TIDE CYCLES, INCLUDING THE DELAWARE AND CHESAPEAKE BAYS AND
THE DELAWARE RIVER. ANOMALIES THIS MORNING ARE RUNNING BETWEEN 2 AND
2.5 FEET ABOVE NORMAL NORTH OF ATLANTIC CITY, AND 2.5 TO 3 FEET
ABOVE NORMAL SOUTH OF ATLANTIC CITY. IN THE DELAWARE BAY, ANOMALIES
ARE AROUND 2.5 FEET ABOVE NORMAL, AND IN THE CHESAPEAKE BAY 1 FOOT
ABOVE NORMAL. A STRONG ONSHORE FLOW SHOULD MAINTAIN THESE ANOMALIES
THROUGH THE HIGH TIDE CYCLE THIS MORNING AND EARLY AFTERNOON. THEN,
AS THE COASTAL LOW CONTINUES TO MOVE SLOWLY NORTH, WINDS WILL
GRADUALLY SHIFT TO THE NORTH, THEN NORTHWEST, WHICH SHOULD EAT AWAY
AT THESE ANOMALIES, PARTICULARLY SOUTH OF ATLANTIC CITY. LOWER ANOMALIES
COMBINED WITH A SMALLER ASTRONOMICAL CONTRIBUTION (0.5 TO 1.0 FOOT
LOWER) SHOULD KEEP ANY ADDITIONAL TIDAL FLOODING DURING THE NEXT
HIGH TIDE CYCLE TONIGHT IN THE MINOR RANGE FROM ATLANTIC CITY SOUTH.
SO...MODERATE FLOODING EXPECTED ALONG THE COAST AND ASSOCIATED
BACKBAYS WITH THIS MORNINGS HIGH TIDE, MODERATE FLOODING EXPECTED
ALONG THE SHORES OF THE LOWER DELAWARE BAY, AND MINOR TO LOW END
MODERATE FLOODING EXPECTED ON THE UPPER DELAWARE BAY. MINOR TIDAL
FLOODING IS A POSSIBILITY ON THE TIDAL DELAWARE (NORTH OF REEDY
POINT, INCLUDING PHILADELPHIA), AND AN ADVISORY MAY BE NEEDED.
ELEVATED WATER LEVELS ARE OCCURRING IN THE NORTHERN PORTIONS OF THE
CHESAPEAKE BAY, BUT NO FLOODING IS EXPECTED. AS ALWAYS, ROUGH SURF
AND HEAVY RAIN AT THE TIME OF HIGH TIDE WILL EXACERBATE THE FLOODING
ISSUE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ070-071-101>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
PAZ060>062.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ008>010-012>020-022-
025>027.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NJZ016.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NJZ001-007.
DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
DEZ001.
MD...FLOOD WATCH THROUGH LATE TONIGHT FOR MDZ008.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/O`HARA
MARINE...DRAG/O`HARA
HYDROLOGY...DRAG
TIDES/COASTAL FLOODING...MIKETA
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
652 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WATCH: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO
CHANGE TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS
THAN FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CUT THE SE TIER AT 630 AM AND CHANGED
TO HEAVIER ICE ACCUMS THE REMAINING ADVISORY AND ALSO THE WINTER
STORM WARNING. STILL SLEET IN SUSSEX COUNTY NJ.
WE MAY NEED TO ISSUE NEW ADVISORIES FOR EARLY WEDNESDAY AS
BACKSIDE BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL
WAA OVER NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT
SIDE OF THE 700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL
SEVERAL HOURS OF MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY
WINDS AS WELL MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR
FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR IN RAIN..SOME HEAVY WITH FREEZING RAIN AT KRDG AND
KABE FOR A LITTLE WHILE THIS MORNING. GUSTY NORTH WINDS TO 2O TO
30 KT EXCEPT NEAR 40 KT VCNTY KACY. CONDITIONS SHOULD IMPROVE THIS
AFTERNOON AS HEAVY RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE
NORTH NORTHWEST. GUSTS DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR ZONES INCLUDING PARTS
OF SOUTHERN NEW JERSEY WHERE 1.5 TO POSSIBLY 3 INCHES OF RAIN IS
EXPECTED TO FALL THROUGH THIS EVENING. THE RAIN, HEAVY AT TIMES,
WILL ADD TO THE ALREADY WET ANTECEDENT CONDITIONS ACROSS THE
REGION. THIS WILL ALLOW FOR BETTER RUNOFF INTO AREAS STREAMS AND
CREEKS AND SOME OF THE SMALLER RIVERS...THE MAINSTEM RIVERS SHOULD
REMAIN WITHIN THEIR BANKS.
HEAVIEST APPEARS TO BE NNJ AND COASTAL NJ.
SO FAR AS OF 530 AM: MANY REPORTS 1 TO 1.9 INCHES IN CAPE MAY...BURLINGTON
AND ATLANTIC COUNTIES SINCE THE RAIN BEGAN AROUND MIDNIGHT.
THE MAIN AREA OF DOUBT IS THE SW END OF THE WATCH IN NORTHERN DE WHERE
RAINFALL LOOKS TO BE LESS THAN 1.5 INCHES. I COULD SEE THIS PART
OF THE WATCH BEING CANCELLED LATER THIS MORNING.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
NOT SURE IF WE WILL REACH ADVISORY CRITERIA UPPER DE BAY BUT
CONTINUING THE HEADLINE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ070-071-101>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
PAZ060>062.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ008>010-012>020-022-
025>027.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR NJZ016.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NJZ001-007.
DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR DEZ001.
MD...FLOOD WATCH THROUGH LATE TONIGHT FOR MDZ008.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...DRAG 652A
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/O`HARA
MARINE...DRAG/O`HARA
HYDROLOGY...
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
539 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OFF THE MIDDLE ATLANTIC COAST TODAY
WHILE MOVING NORTHWARD THROUGH WEDNESDAY. THE STORM WILL SLOWLY
WEAKENS AND MEANDER NORTHEASTWARD FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE IN THE OHIO VALLEY WILL BECOME THE PRIMARY INFLUENCE
FOR OUR WEATHER THIS COMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MULTI-FACETED HAZARD HEADLINE EVENT IN PROGRESS.
FOCUSING ON IMPACTS AND BRIEFLY DISCUSSING SCIENCE WHERE IT MAY BE
HELPFUL.
FLOOD WATCH: WE MAY NEED TO CANCEL THE SW PORTION OF THE FLOOD
WATCH IN OUR MID OR LATE MORNING UPDATE. IT LOOKS TO ME PER THE
RECENT GFS AND HRRR AS WELL AS RADAR THAT THE GREATER RISK FOR
REPEAT EPISODES OF HEAVY RAIN TODAY WILL BE COASTAL AND NORTHERN NJ
AND MAYBE NEAR OR JUST NORTH OF KRDG.
COASTAL FLOOD WATCH: HAZARD ON TARGET WITH MDT FLOODING ASSURED
AND IT MAY BE A STRONG MODERATE DOWN IN THE CAPE MAY-LEWES AREA.
SURGE OF 2 TO POSSIBLY 3 FEET AT HIGH TIDE THIS MORNING. SANDY
HOOK LINKED COUNTIES I THINK MAY ESCAPE MDT FLOODING BUT NO
CHANGE TO THE WARNING. DEPARTURES AT SANDY HOOK ABOUT A FOOT LESS
THAN FURTHER SOUTH WHERE STRONGER INFLOW AND LOWER PRESSURE.
WIND ADVY: BEST POTENTIAL WHERE DESCRIBED ...MAY NEED TO ADD ATLANTIC
COUNTY AT THE LAST MINUTE. FEW GUSTS OF 45 KT EXPECTED MID OR LATE
MORNING. AT 5 AM ..MANY REPORTS AROUND 40 KT DE COAST TO MD ATLANTIC
COAST BORDERING DE.
WINTER WEATHER ADVISORIES: CONTINUE AS DESCRIBED. AT 630AM WILL
DROP THE SE TIER OF COUNTIES.
WE MAY NEED TO ISSUE NEW ONES FOR EARLY WEDNESDAY AS BACKSIDE
BANDING DEVELOPS ON BACK BENT MID LEVEL FRONT AND STILL WAA OVER
NYS AND NEW ENGLAND DRIVING LIFT IN THE FAVORABLE LEFT SIDE OF THE
700 LOW. THIS NEEDS TO BE WATCHED FOR POTENTIAL SEVERAL HOURS OF
MODERATE TO HEAVY WET SNOW EARLY WEDNESDAY. GUSTY WINDS AS WELL
MAY ADD TO THE PROBLEMS AS TEMPS FALL TO NEAR FREEZING.
WINTER STORM WARNING EXTENDED TO 18Z WED TO CAPTURE BACKSIDE SNOW.
THIS IS THE MOST UNCERTAIN PART OF THE FORECAST. NEARLY ISOTHERMAL
VERTICAL THERMAL PROFILE WESTERN PORTION OF CARBON/MONROE COUNTY
WITH EXPECTED MXD FREEZING/FROZEN PCPN AT THE START CHANGING TO A
PERIOD OF HEAVY SNOW THIS MORNING. THEN THE LIFT WEAKENS LATE
MORNING AND IT MAY TURN TO RAIN OR FREEZING THERE THIS AFTERNOON.
TONIGHT THE TEMPERATURES ALOFT COOL AND THEN WE LOOK FOR POTENTIAL
BANDING AND IF THIS OCCURS...ADDITIONAL MDT OR HEAVY SNOWFALL
WOULD OCCUR. DIFFICULT FORECAST AND WE`RE TRYING TO SLICE THIS
VERY CLOSE TO THE MARK. A WORRISOME FORECAST ON PTYPE.
AT 5AM..SE MONROE COUNTY HEAVY SLEET AND FREEZING RAIN. WE ARE
GETTING REPORTS OF FREEZING RAIN IN ALLAMUCHY (.1 GLAZE) AND
OXFORD NJ HAS SOME SLEET AND FREEZING RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PLEASE SEE NEAR TERM FOR SOME INFO AND CONTINUE THE THEME WRITTEN
IN THE AFD FROM YESTERDAY AFTERNOON.
EXPECT A GOOD CHUNK OF THE SNOWFALL TO OCCUR ON THE BACKSIDE OF
THIS SYSTEM LATER TONIGHT AS STRONGER OMEGA AND FGEN COME TOGETHER.
MOSTLY BASED ON WHERE WE THINK THE BACKSIDE DEFORMATION ZONE WILL
SETUP...IN PENNSYLVANIA. SNOWFALL RATES COULD BE PRETTY HEFTY
ACROSS OUR EASTERN PA ZONES WEST OF PHILADELPHIA DOYLESTOWN AND
ALLENTOWN OVERNIGHT (EXCT SNOW GROWTH AND I THINK POTENTIAL FOR
4+ IF THE MODELED SCENARIO VERIFIES) AS WE SEE THE TRANSITION
FROM RAIN BACK TO SNOW. STILL THINK A SWATH OF 8-10 INCHES IS VERY
POSSIBLE WITH HIGHER AMOUNTS IN THE HIGHER ELEVATIONS WESTERN
MONROE AND WESTERN CARBON COUNTIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...MUCH OF THE AREA IS STILL UNDER
THE INFLUENCE OF THE STRONG LOW WHICH WILL MEANDER NORTH/EAST OF
THE REGION. BANDS OF SNOW AND RAIN WILL BE ACROSS THE AREA WITH
ACCUMS POSSIBLE MOSTLY N/W. GFS MODEL OVERNIGHT PAINTS SIGNIFICANT
SNOWS LEHIGH VALLEY NORTH AND WEST...BUT THIS WAS TONED DOWN
SOMEWHAT WITH AN EC SOLUTION MORE LIKELY. WE COULD ADD 1 TO 2
INCHES TO SNOW TOTALS WED N/W.
THURSDAY AND THURSDAY NIGHT...COLD WITH GUSTY WINDS AND A FEW SNOW
SHOWERS AS THE LOW STARTS TO RELAX ITS GRIP OVER THE AREA. CHC
POPS N/W AND SLGT CHC POPS S/E...THESE POPS DECREASE THU NIGHT.
FRI THRU MONDAY...HIGH PRESSURE BUILDS IN AND SEVERAL DRY DAYS
EXPECTED. MODERATING TEMPS...WITH READINGS 4 OR 5 DEGREES BELOW
NORMAL SAT THEN RISING TO NEAR NORMAL BY MONDAY.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...IFR IN RAIN..SOME HEAVY WITH FREEZING RAIN AT KRDG AND
KABE FOR A LITTLE WHILE THIS MORNING. GUSTY NORTH WINDS TO 2O TO
30 KT EXCEPT NEAR 40 KT VCNTY KACY. CONDITIONS SHOULD IMPROVE THIS
AFTERNOON AS HEAVY RAIN LIFTS NORTH AND WINDS TURN SLIGHTLY MORE
NORTH NORTHWEST. GUSTS DIMINISH LATE TODAY.
TONIGHT...MVFR CIGS WITH BANDS OF RAIN SHIFTING SOUTHEASTWARD AND
RAIN CHANGING TO WET SNOW AT KRDG AND KABE. NORTH TO NORTHWEST
WINDS GUST 20 TO 30 KT.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY: SOME RESTRICTIONS TO MVFR OR IFR IN
BANDS OF RAIN AND SNOW SHOWERS. NORTHWEST WIND GUSTS 20-30 KNOTS AT
TIMES.
FRIDAY: VFR...A FEW WIDELY SCT SHOWERS FAR N/W EARLY.
SATURDAY: VFR.
&&
.MARINE...
GALE WARNING CONTINUES ON OUR WATERS WITH NO CHANGES. THERE COULD
BE SOME STORM FORCE GUSTS ACROSS THE WATERS THIS MORNING-MIDDAY BUT
CONFIDENCE NOT HIGH ENOUGH TO ISSUE A STORM WARNING NOR DO WE THINK
THEY WILL BE PERSISTENT. SEAS WILL CONTINUE TO BUILD UPWARDS OF 15
FEET ACROSS A MAJORITY OF OUR WATERS....POSSIBLY BRIEFLY 17 OR 18
FT AT 44009.
WINDS SUBSIDE LATE TODAY OR TONIGHT WITH THE PRESSURE GRADIENT
WEAKENING ON THE SOUTHWEST SIDE OF THE LOW PARKED EAST BELMAR. SCA
CONDITIONS.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT: HIGH END SCA CONDITIONS WITH GALE GUSTS
POSSIBLE. SEAS MOSTLY 5 TO 9 FEET.
THURSDAY AND THURSDAY NIGHT: SCA SEAS AND GUSTS CONTINUE WITH LOW
PRESSURE STILL TO NORTHEAST.
FRIDAY AND SATURDAY: NO HEADLINES EXPECTED ATTM.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR THE I-95 CORRIDOR ZONES INCLUDING PARTS
OF SOUTHERN NEW JERSEY WHERE 1.5 TO POSSIBLY 3 INCHES OF RAIN IS
EXPECTED TO FALL THROUGH THIS EVENING. THE RAIN, HEAVY AT TIMES,
WILL ADD TO THE ALREADY WET ANTECEDENT CONDITIONS ACROSS THE
REGION. THIS WILL ALLOW FOR BETTER RUNOFF INTO AREAS STREAMS AND
CREEKS AND SOME OF THE SMALLER RIVERS...THE MAINSTEM RIVERS SHOULD
REMAIN WITHIN THEIR BANKS.
HEAVIEST APPEARS TO BE NNJ AND COASTAL NJ.
SO FAR AS OF 530 AM: MANY REPORTS 1 TO 1.9 INCHES IN CAPE MAY...BURLINGTON
AND ATLANTIC COUNTIES SINCE THE RAIN BEGAN AROUND MIDNIGHT.
THE MAIN AREA OF DOUBT IS THE SW END OF THE WATCH IN NORTHERN DE WHERE
RAINFALL LOOKS TO BE LESS THAN 1.5 INCHES. I COULD SEE THIS PART
OF THE WATCH BEING CANCELLED LATER THIS MORNING.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD WARNING CONTINUES AS NOTED IN THE NEAR TERM SECTION.
NOT SURE IF WE WILL REACH ADVISORY CRITERIA UPPER DE BAY BUT
CONTINUING THE HEADLINE.
&&
.CLIMATE...
RECORD RAINFALLS FOR TUESDAY IN OUR HISTORICAL DATABASE.
ACY 2.51 2009
PHL 2.13 2009
ILG 2.28 2009
ABE 1.51 1973
TTN 2.25 1978
GED 1.93 2009
RDG 1.16 2009
MPO 1.82 1974
RECORD SNOWFALL FOR WEDNESDAY (LONG SHOT BUT JUST IN CASE)
PHL 4.3 1904
ILG 2.9 2013
ABE 2.7 2013
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ070-071-101>106.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ101>106.
WINTER STORM WARNING UNTIL 1 PM EST WEDNESDAY FOR PAZ054-055.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
PAZ060>062.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ008>010-012>020-022-
025>027.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
NJZ008>010-015.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020>027.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ012>014-020-
022-025>027.
COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR NJZ016.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NJZ001-007.
DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001.
COASTAL FLOOD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
DEZ002>004.
COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR DEZ001.
MD...FLOOD WATCH THROUGH LATE TONIGHT FOR MDZ008.
MARINE...GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...DRAG 539
SHORT TERM...DRAG 539
LONG TERM...O`HARA
AVIATION...DRAG/O`HARA 539
MARINE...DRAG/O`HARA
HYDROLOGY...539
TIDES/COASTAL FLOODING...539
CLIMATE...
AREA FORECAST DISCUSSION
NWS MIAMI FL
1229 AM EST TUE DEC 9 2014
.AVIATION...
COLD FRONT WILL BE MOVING ACROSS SOUTH FLORIDA EARLY IN THE
FORECAST FOLLOWED BY POSSIBLE IFR CIGS. KPBI HAS ALREADY BECOME
BKN006 BUT FOR NOW KEPT ALL OTHER TERMINALS AT BKN010-015 BUT MAY
HAVE TO AMEND IF THE LOWER CIGS PAN OUT. HIGH RESOLUTION SHORT
TERM GUIDANCE KEEPS CIGS AT MVFR BEFORE CLEARING OUT AT MID DAY.
SURFACE WIND WILL BE W-NW AT 8-10KT BUT COULD HAVE BRIEF GUSTS
APPROACHING 20KT AT A FEW LOCATIONS.
KOB
&&
.PREV DISCUSSION... /ISSUED 838 PM EST MON DEC 8 2014/
UPDATE...
NO MAJOR CHANGES TO THE FORECAST THIS EVENING. SOME ADJUSTMENTS T
POPS TO REFLECT CURRENT OBSERVATIONS AND MODEL TRENDS FOR TONIGHT.
ALSO, THE SREF IS SHOWING THE BEST CHANCES OF FOG TO BE FURTHER
SOUTH THAN ORIGINALLY FORECAST. IT IS ALSO SHOWING THAT IT IS
POSSIBLE THE BROWARD/MIAMI-DADE METRO AREAS MAY ALSO HAVE SOME
CHANCE OF SEEING FOG IN THE MORNING. BUT, HAVE KEPT IT OUT OF
THOSE AREAS FOR NOW, WITH THE INTERIOR BEING THE MAIN AREA
IMPACTED BY PATCHY FOG. HOWEVER, THE LATEST RUN OF THE HRRR IS
ALSO SHOWING THE METRO AREAS BEING IMPACTED WITH FOG, INCLUDING
THE PALM BEACH AREA. SO, THIS MAY NEED TO BE ADDED IN WITH THE
NEXT UPDATE.
PREV DISCUSSION... /ISSUED 659 PM EST MON DEC 8 2014/
AVIATION...
VFR CONDITIONS WILL PERSIST THROUGH THE BULK OF THE PERIOD WITH
LIGHT NW LOW-LEVEL FLOW CONTINUING. THERE IS SOME DISAGREEMENT
BETWEEN GFS/NAM AND HRRR/RAP ON REGARD TO PATCHY FOG/LOW CIGS
TONIGHT INTO TUESDAY MORNING ACROSS PORTIONS OF THE AREA ONCE
AGAIN. WITH THE LOW CONFIDENCE INCLUDED VFR CONDITIONS WITH A FEW
AND SCT LOW CLOUDS.
PREV DISCUSSION... /ISSUED 345 PM EST MON DEC 8 2014/
DISCUSSION...
THE MAIN SURFACE SYNOPTIC FEATURES ACROSS THE REGION INCLUDE A
SURFACE LOW IN THE VICINITY OF BERMUDA WITH A TRAILING COLD FRONT
ACROSS THE CENTRAL BAHAMAS AND THE FLORIDA STRAITS. IN ADDITION
THERE IS A WEAK SURFACE TROUGH TO THE NORTHWEST OF THE FLORIDA
PANHANDLE.
AT THE MID TO UPPER LEVELS THERE IS A LARGE AMPLITUDE MID TO UPPER
LEVEL TROUGH WEST OF THE GREAT LAKES EXTENDING SOUTHWARD TO THE
NORTHERN GULF. THE MID TO UPPER LEVEL TROUGH IS FORECAST TO SHIFT
EASTWARD INTO THE EASTERN GULF TONIGHT WITH A RE-ENFORCING
SURFACE BOUNDARY MOVING INTO THE FLORIDA PENINSULA TONIGHT. THIS
WILL MAINTAIN NORTHERLY WINDS ACROSS THE REGION TONIGHT INTO
TUESDAY WITH ADDITIONAL COLD AIR ADVECTION.
THE COMBINATION OF COOLER AIR AND LINGERING MOISTURE COULD RESULT
IN FOG ACROSS SOUTH FLORIDA EARLY TUESDAY MORNING. THE MOST RECENT
MODEL GUIDANCE ALSO SUGGESTS A CHANCE OF FOG EARLY TUESDAY AND IS
INDICATED IN THE FORECAST.
AS NOTED EARLIER...THE COMBINATION OF A PERSISTENT PRESSURE
GRADIENT AND WELL ESTABLISHED NORTHEAST FETCH ACROSS THE WESTERN
ATLANTIC EAST OF THE CAROLINAS IS FORECAST TO PRODUCE LONG PERIOD
NORHTHEASTERLY SWELL THAT WILL CONTINUE TO ENTER THE ATLANTIC
WATERS EAST OF PALM BEACH COUNTY TODAY. THE LONG PERIOD SWELL WILL
CONTINUE TO ENTER THE REGIONAL ATLANTIC WATERS TONIGHT INTO
TUESDAY AND FORECAST TO CONTINUE THROUGH AT LEAST WEDNESDAY. THIS
PROMPTED THE ISSUANCE OF A HIGH RISK OF RIP CURRENTS FOR THE
ATLANTIC COAST BEACHES TODAY THROUGH WEDNESDAY EVENING. IN
ADDITION...A HIGH SURF ADVISORY IS IN EFFECT FOR TUESDAY MORNING
THROUGH WEDNESDAY MORNING FOR THE BEACHES OF PALM BEACH COUNTY
WITH SURF HEIGHTS FORECAST TO BE NEAR 10 FEET BY EARLY TUESDAY
MORNING.
FOR THE FORECAST TUESDAY THROUGH FRIDAY...MAINLY DRY AND STABLE
CONDITIONS AND NORTHERLY TO NORTHWESTERLY WINDS ARE FORECAST
THROUGH THIS PERIOD WITH UNSEASONABLY COOLER TEMPERATURES
PREVAILING.
MARINE...
AS MENTIONED ABOVE...LONG PERIOD NORHTHEASTERLY SWELL WILL
CONTINUE TO ENTER THE ATLANTIC WATERS EAST OF PALM BEACH COUNTY
TODAY THEN CONTINUE TO ENTER THE ATLANTIC WATERS TONIGHT INTO
TUESDAY AND FORECAST TO CONTINUE THROUGH AT LEAST WEDNESDAY. IN
ADDITION NORTHWESTERLY WINDS IN THE 15 TO 20 KNOT RANGE ARE
FORECAST TO BUILD INTO THE REGIONAL WATERS ON TUESDAY. WINDS
ACROSS THE ALTANTIC WATERS COULD REACH THE 20-22 KNOT RANGE LATER
ON TUESDAY. THE COMBINATION OF THE BUILDING SWELL AND WINDS TO
ADVISORY LEVELS WILL RESULT IN HAZARDOUS SEAS ACROSS THE ATLANTIC
WATERS WITH SMALL CRAFT ADVISORY IN EFFECT ALL ATLANTIC WATERS
THIS EVENING THROUGH WEDNESDAY EVENING.
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH WEDNESDAY EVENING FOR FLZ168-172-
173.
HIGH SURF ADVISORY FROM 7 AM THIS MORNING TO 10 AM EST WEDNESDAY
FOR FLZ168.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EST WEDNESDAY FOR AMZ650-651-670-
671.
HIGH RIP CURRENT RISK THROUGH WEDNESDAY EVENING FOR AMZ630.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1204 AM CST TUE DEC 9 2014
.UPDATE...
843 PM CST
FOR EVENING UPDATE...
UPDATED FORECAST TO REMOVE MUCH OF THE FOG AS VISIBILITY HAS
IMPROVED MARKEDLY FROM EARLIER. ALSO ADJUSTED POP/WEATHER FOR LIGHT
RAIN/SNOW COMBO CHANGING TO LIGHT SNOW PRIOR TO ENDING AFTER
MIDNIGHT.
SURFACE LOW PRESSURE WAS DRIFTING SOUTHEAST ACROSS THE WESTERN GREAT
LAKES REGION THIS EVENING...WITH OCCLUDED COLD FRONT NOW PUSHING
EAST ACROSS THE LAKE AND NORTHWEST INDIANA AS OF 02Z/8 PM CST.
INTRUSION OF SOMEWHAT DRIER LOW LEVEL AIR HAS HELPED ERODE MUCH OF
THE FOG AND LOWEST CLOUD BASES BEHIND THE FRONT...THUS HAVE REMOVED
FOG FROM FORECAST EXCEPT FOR NEXT FEW HOURS OVER THE LAKE.
ALOFT...ROBUST MID-LEVEL SHORT WAVE CIRCULATION WAS NEARLY OVERHEAD
PER CURRENT WATER VAPOR IMAGERY AND 00Z RAOB ANALYSIS...AND IS NI
THE PROCESS OF FORMING A CLOSED MID-LEVEL LOW CENTER WHICH WILL
CONTINUE TO SLIDE OFF TO THE SOUTHEAST OF THE AREA OVERNIGHT.
REGIONAL RADAR MOSAIC DEPICTS LIGHT PRECIPITATION ASSOCIATED WITH
THIS FEATURE MAINLY ALONG ITS NORTHERN/EASTERN FLANKS...GENERALLY
THE NORTHEAST HALF OR SO OF THE WFO LOT CWA. 00Z SOUNDINGS FROM DVN
AND ILX SHOW MOISTURE GENERALLY BELOW 800-700 MB AND WITH CLOUD
BEARING LAYER MIN TEMPS LESS THAN -10 C...RESULTING IN MAINLY
DRIZZLE AND LIGHT RAIN WITH LACK OF ICE NUCLEATION. DEEPER MOISTURE
FARTHER NORTH (GRB SOUNDING) WAS ASSOCIATED WITH BETTER
PRECIPITATION ELEMENTS CLOSER TO THE MID-LEVEL CIRCULATION ACROSS
EAST/SOUTHEAST WI WAS RESULTING IN WET SNOW. THIS DEEPER MOISTURE
WITH THE MID-LEVEL WAVE AND A SLOW COOLING OF THE COLUMN IN THE WAKE
OF THE COLD FRONT WILL LIKELY ALLOW FOR PRECIP TO MIX/CHANGE TO A
LITTLE WET SNOW WHERE IT FALLS A LITTLE STEADIER...ESPECIALLY ACROSS
FAR NORTHEAST IL THROUGH A LITTLE PAST MIDNIGHT AND INTO NORTHWEST
INDIANA THROUGH EARLY TUESDAY MORNING. LOW SNOW TO LIQUID RATIOS AND
LIGHT NATURE OF PRECIP SHOULD PRECLUDE ANY SIGNIFICANT ACCUMULATIONS
OTHER THAN A FEW SLUSHY TENTHS PERHAPS IN ISOLATED AREAS BEFORE
PRECIPITATION ENDS.
RATZER
&&
.SHORT TERM...
317 PM CST
THROUGH WEDNESDAY...
LIGHT RAIN OR DRIZZLE AND SOME PATCHY LIGHT SNOW ALL ARE LIKELY
TO MAKE AN APPEARANCE THIS EVENING...ALONG WITH AREAS OF FOG.
WATER VAPOR SATELLITE IMAGE SHOWS TWO UPPER CIRCULATIONS THAT WILL
CROSS THE AREA...AND MODEL VORTICITY FIELDS ALOFT AND RH FIELDS AT
LOWER LEVELS ALL SUPPORT THE IDEA OF PATCHY AREAS OF
PRECIPITATION. AS OF LATE AFTERNOON MOST AREAS ARE IN THE MIDDLE
TO UPPER 30S...AND PRECIP CHANCES SHOULD DIMINISH AS COLDER AIR
APPROACHES...SO LITTLE IF ANY FROZEN PRECIPITATION WOULD BE
EXPECTED TO ACCUMULATE.
BY MORNING THE AXIS OF THE UPPER LONGWAVE IS WELL TO OUR EAST...AND
UPPER SHORTWAVE ENERGY BEGINS TO EXIT THE AREA AS WELL. ONLY AT LOW
LEVELS DO RH FIELDS SUGGEST CONTINUED SATURATION...SO WILL TREND
POPS DOWNWARD TO BELOW MENTIONABLE LEVELS BY DAYBREAK EXCEPT
DOWNWIND FROM THE LAKE IN NORTHWEST INDIANA AT THE END OF A
NORTHWEST FETCH. EVEN THAT AREA APPEARS TO DRY OUT BY LATE
TOMORROW AS WINDS CONTINUE VEERING NORTHEASTERLY AND LOW LEVELS
DRY CONSIDERABLY.
CLOUDINESS PERSISTS SOUTH OF THE LAKE LATE TOMORROW INTO TOMORROW
NIGHT...BUT AREAS WEST CLEAR OUT A BIT. THIS ACCOUNTS FOR A FEW
DEGREE TEMPERATURE DIFFERENCE IN TUESDAY NIGHT LOWS BETWEEN MORE
CLEAR AND MORE OVERCAST AREAS. WEDNESDAY CONTINUES COOL...BUT NOT
UNSEASONABLY SO...WITH GRADUALLY CLEARING SKIES.
LENNING
&&
.LONG TERM...
317 PM CST
WEDNESDAY NIGHT THROUGH TUESDAY...
THE REMAINDER OF THE WEEK AND ESPECIALLY THE WEEKEND DO NOT LOOK
TOO BAD AT ALL FOR MID DECEMBER. COMPARED TO LAST MONTH...THE
STRETCH OF DAYS STARTING ON FRIDAY THE 12TH LOOKS TO BE FROM 10 TO
20 DEGREES WARMER THAN THE SAME PERIOD FROM LAST MONTH. SO THE
MIDDLE PORTIONS OF NOVEMBER AND DECEMBER APPEAR TO BE SWAPPED THIS
YEAR.
MODELS ARE IN REASONABLE THOUGH NOT PERFECT AGREEMENT THAT THE LARGE
UPPER TROUGH NOW OVERHEAD WILL MOVE INTO THE EASTERN CONUS AND ALLOW
A BROAD RIDGE FROM THE SFC TO UPPER LEVELS TAKE ITS PLACE. THIS
RIDGING WITH ITS DRY AND MILD WEATHER APPEARS TO PERSIST AT LEAST
INTO THE MIDDLE PART OF THE WEEKEND WHILE SLOWLY DRIFTING EAST.
BY EARLY SUNDAY MODELS START TO SUGGEST A RETURN OF BETTER MOISTURE
AHEAD OF AN APPROACHING FRONTAL ZONE ACROSS THE PLAINS AND WEST OF
THE RIDGE. CONFIDENCE ON THE TIMING OF THIS MOIST SOUTHERLY FLOW
INTO THE LOCAL AREA IS LOW...SO HAVE ELECTED TO INCLUDE INCREASED
POPS BY SUNDAY AND MONDAY BUT ALL IN THE FORM OF LIGHT RAIN.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* LOW END MVFR CIGS THROUGH THE MORNING WITH SOME INTERMITTENT IFR
CIGS POSSIBLE THE NEXT FEW HOURS. CIGS GRADUALLY RISE BUT REMAIN
MVFR INTO THIS EVENING/OVERNIGHT.
* -DZ THROUGH EARLY MORNING WITH SCATTERED -RASN SHOWERS PRIOR TO 09
OR 10Z. BRIEF MVFR VSBY POSSIBLE.
* WEST-NORTHWEST WINDS SHIFT NORTHWEST OVERNIGHT AND NORTH INTO
EARLY AFTERNOON. GUSTS AROUND 20 KT THIS AFTERNOON.
MDB
//DISCUSSION...UPDATED 06Z...
LATEST OBSERVATIONS SHOW A MIX OF IFR AND LOW MVFR CIGS ACROSS THE
REGION WHICH IS COMPLICATING FORECAST DETAILS. EXPECT THAT LOW
MVFR WILL TAKE OVER AS THE MAIN CIG HEIGHT THROUGH THE OVERNIGHT
WITH SOME VARIABILITY BETWEEN MVFR/IFR PRIOR TO THAT. DRIZZLE
APPEARS TO BE DECREASING IN COVERAGE BUT WILL BE CONTINUING FOR A
FEW HOURS. A PASSING UPPER WAVE CONTINUES TO PRODUCE SOME -RASN
SHOWERS BUT COVERAGE OF THESE IS ALSO DECLINING. WINDS WILL BE
TURNING MORE NORTHWESTERLY OVERNIGHT...WITH GYY STARTING TO SEE
SOME GUSTS AS TRAJECTORY ACROSS LAKE MICHIGAN INCREASES.
CIGS LOOK TO REMAIN IN PLACE THROUGH THE AFTERNOON AND PROBABLY
THE EVENING FOR MOST AREAS. THERE SHOULD BE A GRADUAL RISING OF
BASES BUT THINGS MAY BE HARD PRESSED TO RISE ABOVE 2000 FT BEFORE
MID/LATE AFTERNOON. TIMING OF INCREASES WILL LIKELY NEED
ADJUSTMENT. WINDS WILL TURN NORTH-NORTHWEST OR EVEN DUE NORTH INTO
THE AFTERNOON WITH GUSTS TO AROUND 20 KT DEVELOPING. GYY MAY SEE
GUSTS INTO THE MID OR EVEN UPPER 20S AS THE FETCH DOWN LAKE
MICHIGAN INCREASES. LAKE EFFECT SHOWERS WILL LIKELY DEVELOP AND
MAY IMPACT GYY GIVEN THE NORTH WIND BUT THE BULK OF THE ACTIVITY
MAY BE JUST TO THE EAST. HAVE ADDED VCSH MENTION FOR MOST OF THE
DAY. CIGS MAY TRY TO SCATTER FROM THE NORTHWEST INTO THE EVENING
BUT A NORTH-NORTHEAST FLOW IN THE CLOUD BEARING LAYER OFF THE LAKE
WILL LIKELY KEEP AT LEAST SOME MVFR CIGS ACROSS THE CHICAGO METRO
AREA...WITH STEADIER CIGS OVER NORTHWEST INDIANA.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN MVFR CIGS PERSISTING THROUGH AT LEAST THE
AFTERNOON. MEDIUM CONFIDENCE IN AT LEAST SOME RISING OF CIG
BASES THIS AFTERNOON BUT LOW CONFIDENCE IN HOW QUICKLY IT MAY
OCCUR. MEDIUM CONFIDENCE IN INTERMITTENT IFR CIGS OVERNIGHT.
* HIGH CONFIDENCE IN -DZ PERSISTING WITH A DECREASE IN -RASN
SHOWERS INTO EARLY MORNING.
* HIGH CONFIDENCE IN WIND TRENDS.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...MVFR CIGS POSSIBLE EARLY...THEN VFR. NORTH WINDS.
THURSDAY...VFR. WEST WINDS.
FRIDAY...MAINLY VFR. MVFR CIGS POSSIBLE AT NIGHT. SOUTHWEST WINDS.
SATURDAY...MVFR CIGS POSSIBLE. SOUTH WINDS.
SUNDAY...MVFR CIGS POSSIBLE. SLGT CHANCE OF RAIN. SOUTH WINDS.
RATZER
&&
.MARINE...
227 PM CST
LOW PRESSURE IS OVER NORTHERN WISCONSIN AND IT WILL WEAKEN AS IT
MOVES ACROSS THE LAKE TONIGHT. WINDS TURN NORTHWEST BEHIND THE LOWS
COLD FRONT AND THEN THEY TURN NORTH AS HIGH PRESSURE BUILDS OVER
MINNESOTA. THE GRADIENT TIGHTENS BETWEEN THE HIGH AND LOW WITH 30 KT
NORTH WINDS EXPECTED ACROSS THE LAKE TOMORROW. WINDS AND WAVES WILL
INCREASE IN THE NEARSHORE WATERS SO HOISTED A SMALL CRAFT ADVISORY
BEGINNING EARLY TUESDAY MORNING. WINDS DIMINISH TUESDAY NIGHT AS
THE HIGH APPROACHES BUT LARGE WAVES WILL LINGER IN THE NSH ZONES.
HAVE MEDIUM CONFIDENCE IN HOW LONG THE HAZARDOUS WAVES WILL
LINGER...BUT HAVE THE SMALL CRAFT ADVISORY GOING INTO WEDNESDAY
NIGHT. NORTH WINDS BECOME NORTHWEST AS THE HIGH MOVES DOWN THE
MISSISSIPPI VALLEY WEDNESDAY NIGHT AND CONTINUE TO BACK TO SOUTHWEST
BY FRIDAY AFTERNOON. THE HIGH FINALLY SHIFTS EAST OVER THE OHIO
VALLEY SATURDAY WITH THE NEXT LOW FORMING OVER THE PLAINS SATURDAY
NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...6 AM TUESDAY TO 9
PM WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...9 AM TUESDAY TO 3
PM WEDNESDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1112 PM CST Mon Dec 8 2014
.UPDATE...
ISSUED AT 825 PM CST MON DEC 8 2014
Cold front has swept east of the state early this evening along
with most of the light rain and drizzle. Low level flow has now
shifted into the northwest and as a result, the cloud band that
was shifting out of far west central Illinois this evening has
been replaced by another band of clouds that was tracking
southeast out of Iowa this afternoon and will be with us well
into the morning hours of Tuesday. Not much in the way of precip
over Iowa early this evening with the only snow and rain reports
well to our north over far southern Wisconsin and northern IL.
Most of the short term models suggest that light precip will remain
to our north tonight. Current forecast has conditions well in hand
for this evening and the overnight hours. Other than some minor
wording adjustments in the overnight portion of the forecast, no
other changes needed to the current ZFP. Will have the update out
by 900 pm.
&&
.SHORT TERM...(Tonight)
ISSUED AT 248 PM CST MON DEC 8 2014
Cold front is pushing across central Illinois early this afternoon,
located just west of Peoria and Springfield as of 2 pm. Extensive
low cloud deck has been prevailing over the forecast area, with some
localized dense fog along and north of the I-74 corridor. Surface
observations showing visibilities and ceilings lifting behind the
front, and the back edge of the cloudiness covered about the eastern
third of Missouri. Well defined upper circulation evident on water
vapor imagery over northeast Iowa, and this is producing some light
rain and snow upstream from us.
Main question for this part of the forecast is how much clearing
will manage to take place. Lower clouds extend all the way back into
southern North Dakota. RAP model guidance and current trajectories
would suggest some clearing may take place over the far southwest
parts of the forecast area for a short period, but a secondary surge
of clouds is expected as the broad upper trough surrounding the
aforementioned circulation swings through the Midwest this evening.
Have kept the sky forecast on the pessimistic side and kept cloudy
skies in the grids for tonight. Much of the associated precipitation
should be just to our north, but will include some slight chance
PoP`s for the northeast CWA for this evening.
&&
.LONG TERM...(Tuesday through Monday)
ISSUED AT 248 PM CST MON DEC 8 2014
As the low pressure area weakens and gets absorbed into an east
coast system, a high pressure ridges will build into the area. This
ridge will dominate the weather over the area through Wednesday and
beyond. Some concern with lower level moisture remaining trapped
under the ridge Tue through Wed, so have increased cloud cover to go
mostly cloudy through Wed. As the center of the high pressure drops
south into the southern Miss river valley, the ridge will remain
over the area with dry weather through Thursday, the rest of the
week and into the weekend. The area will also remain dominated by
mid level cyclonic flow through the end of the week. Then mid level
ridging, that was building in the plains, will begin to dominate the
region for the weekend. Late in the weekend, the ridging will begin
to push east and this will allow a frontal system to move into the
area and bring rain to the region for Sun night and Monday.
With high pressure dropping into the area and cyclonic flow, temps
will remain cool for the next couple of days. But then as the high
pressure settles south and mid level ridging builds, temps will
begin to warm again. By the weekend, temps will warm to above
normal, with 50s expected Sat and Sun.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1100 PM CST MON DEC 8 2014
MVFR cigs are expected thru Tuesday evening. A rather large storm
system will continue to track off to our east tonight but the
expansive cloud cover associated with the system will linger over
our area at least thru 00z tomorrow. Most of the rain associated
with the system`s cold front was well off to our east late this
evening but the threat for some spotty drizzle will remain over
parts of the area as a secondary upper level wave drifts southeast
thru the region overnight. Based on upstream observations, we look
for cigs to range from 1200 to 2000 feet late tonight thru the
morning hours of Tuesday, before we see a gradual improvement
during the afternoon to between 2000-3000 feet.
Not very confident at this point, at least based on the latest
forecast soundings for later tomorrow as a rather strong low level
inversion is forecast to develop which will effectively trap the
low level moisture. Boundary layer winds are forecast to be more
from a north-northeast direction tomorrow which is not a very good
direction for clearing skies in our area. Surface winds will be
from the northwest to north at 8 to 14 kts tonight, and more from
a northerly direction on Tuesday at 10 to 15 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Geelhart
LONG TERM...Auten
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
950 PM EST WED DEC 10 2014
.UPDATE...
NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 341 PM EST WED DEC 10 2014
A QUIET WEATHER PATTERN WILL BE PLACE OVER CENTRAL INDIANA WITH
SLOWLY WARMING TEMPERATURES AND DRY CONDITIONS THROUGH THE WEEKEND.
THE NEXT CHANCE FOR PRECIPITATION WILL ARRIVE ON MONDAY WITH LOW
PRESSURE MOVING THIS WAY FROM THE PLAINS AND TEMPERATURES LOOK WARM
ENOUGH FOR THIS TO BE RAIN.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 950 PM EST WED DEC 10 2014
.UPDATE...SATELLITE LOOPS INDICATED PARTIAL CLEARING HAS REACHED THE
COUNTIES JUST NORTHEAST OF MUNCIE AND KOKOMO AT 02Z AND RAP 925 MB
RH FIELDS INDICATE DRIER AIR SHOULD SPREAD INTO NORTHEAST AND EAST
CENTRAL PARTS OF OUR FORECAST AREA OVERNIGHT AND INTO THURSDAY.
AS A RESULT WILL FOLLOW THIS TREND TO INDICATE PARTIAL CLEARING
ACROSS OUR NORTHEAST AND EAST CENTRAL SECTIONS LATER TONIGHT.
RAP INDICATES THE WESTERN HALF OF OUR REGION SHOULD REMAIN CLOUDY
OVERNIGHT. LOWERED MINIMUM TEMPERATURES A FEW DEGREES TONIGHT IN
AREAS WHERE SOME CLEARING IS EXPECTED. OTHERWISE...LITTLE CHANGE TO
THE REST OF THE FORECAST.
PREVIOUS NEAR TERM DISCUSSION FOLLOWS...
SATELLITE LOOP INDICATES SOME SCATTERING/CLEARING COULD WORK ITS
WAY IN FROM THE NORTH EARLY TONIGHT. HOWEVER CYCLONIC
FLOW...AMPLE LOW LEVEL MOISTURE AND TRAPPING INVERSION WILL NOT
ALLOW THIS TO LAST FOR LONG. EXPECT THESE CONDITIONS TO CAUSE ANY
AREAS THAT CLEAR TO FILL BACK IN WITH CLOUDS AND THUS KEPT MOSTLY TO
COMPLETELY CLOUDY SKIES OVER THE AREA THROUGH THE NIGHT. LEANED
WARMER THAN GUIDANCE BY A COUPLE DEGREES DUE TO EXPECTED CLOUD COVER.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 950 PM EST WED DEC 10 2014
.UPDATE...OVER AREAS THAT CLEAR TONIGHT...MODEL SOUNDINGS INDICATE
CONTINUED DRYING IN LOWER LEVELS SHOULD CONTINUE INTO THURSDAY.
THUS IT SEEMS UNLIKELY THAT CLOUDS WILL RETURN OVER NORTHEAST OR
EAST CENTRAL SECTIONS ON THURSDAY. AS A RESULT...DECIDED TO UPDATE
SKY COVER GRIDS FOR THURSDAY TO REELECT THIS TREND. LEFT WESTERN
SECTIONS UNCHANGED AS FLOW OFF OF LAKE MICHIGAN MAY KEEP CLOUDS
THERE.
PREVIOUS SHORT TERM DISCUSSION FOLLOWS...
MODELS ARE IN GOOD AGREEMENT AND GENERALLY USED A CONSENSUS WITH THE
EXCEPTION OF CLOUD COVER...WHICH THE MODELS AND GUIDANCE TEND TO
CLEAR MUCH TOO QUICKLY IN THIS PATTERN. FOR THURSDAY AND THURSDAY
NIGHT...EVEN THOUGH HIGH PRESSURE IS TRYING TO BUILD IN...TRAPPING
INVERSION OVER HIGH LOW LEVEL MOISTURE SHOULD KEEP STRATUS DECK IN
PLACE OVER THE AREA FOR MOSTLY CLOUDY SKIES LASTING INTO THURSDAY
NIGHT. COULD SEE SOME SCATTERING THURSDAY NIGHT BUT THEN FILLING
BACK IN TO MOSTLY CLOUDY BY FRIDAY AFTERNOON FOR PARTS OF THE AREA.
WITH UPPER RIDGING BUILDING TOWARD THE AREA AND HIGH PRESSURE EXPECT
DRY CONDITIONS. FOR TEMPERATURES LEANED CLOSER TO RAW MODEL NUMBERS
WITH COOLER HIGHS AND WARMER LOWS DUE TO CLOUD COVER. SHOULD STILL
SEE A SLOW WARMING TREND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 156 PM EST WED DEC 10 2014
UPCOMING PRECIP LOOKS TO MOVE THROUGH THE AREA AS A CLOSED LOW
MONDAY INTO TUESDAY. ENSEMBLES HAVE PRETTY GOOD CONSENSUS ON THIS
EVENT SO POPS WERE INCREASED TO JUST SHY OF LIKELY. OTHERWISE WARMER
THAN NORMAL TEMPS TO BEGIN THE PERIOD WILL END UP NORMAL TO BELOW
NORMAL BY MID WEEK NEXT WEEK. ALLBLEND GUIDANCE SEEMED TO INITIALIZE
THIS PATTERN WELL AND DID NOT NEED TO ALTER THE FORECAST TOO MUCH.
&&
.AVIATION /DISCUSSION FOR THE 11/0300Z TAF UPDATE/...
ISSUED AT 903 PM EST WED DEC 10 2014
UPDATE...
WINDS HAVE BECOME A BIT MORE NORTHWESTERLY THAN NORTHERLY BUT
REMAIN SUSTAINED AROUND 5 KTS.
PREVIOUS DISCUSSION...
PERSISTENT INVERSION IS MAKING IT TOUGH FOR CLOUDS TO SCATTER OUT.
AS A RESULT...MVFR CONDITIONS WILL CONTINUE THROUGH MID MORNING
TOMORROW. AT THAT POINT...THERE SHOULD BE IMPROVEMENT TO VFR
CATEGORY WITH MORE RAPID CLEARING LATE IN THE TAF PERIOD. WINDS
WILL GENERALLY BE NORTHWESTERLY AT 5 TO 10 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/JH
SHORT TERM...CP/JH
LONG TERM....SMF
AVIATION...TDUD
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1140 PM EST MON DEC 8 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 222 PM EST MON DEC 8 2014
A COLD FRONT AND AN UPPER TROUGH WILL KEEP CHANCES FOR PRECIPITATION
ACROSS CENTRAL INDIANA INTO TUESDAY. AFTERWARD HIGH PRESSURE WILL
PROVIDE DRY CONDITIONS THROUGH THE WEEKEND. CHANCES FOR RAIN RETURN
MONDAY. BELOW AVERAGE TEMPERATURES WILL GIVE WAY TO ABOVE NORMAL
READINGS BY THE WEEKEND.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 836 PM EST MON DEC 8 2014
0130Z UPDATE...BASED ON TRENDS THUS FAR THIS EVENING AGREE WITH
PREVIOUS THINKING ON THE OVERNIGHT WEATHER. ONLY CHANGES WERE TO
INCREASE POPS LATE THIS EVENING ON AVERAGE OF 20 PERCENT TO
ACCOUNT FOR THE SECOND WAVE OF VERY LIGHT RAIN AND/OR DRIZZLE
MOVING IN FROM CENTRAL ILLINOIS. LATEST RUNS SHOW HRRR AND SREF
HAVE BACKED OFF ON POPS CONSIDERABLY AFTER 06Z...WHICH WILL BE
POST FRONTAL PASSAGE...SO LEFT POPS AS IS AFTER THIS TIME.
WILL NEED TO MONITOR TEMPERATURES ESPECIALLY AFTER 06Z AND FOR
ANY ADDITIONAL SIGNIFICANT PRECIP DEVELOPMENT...BECAUSE IF TEMPS
PLUMMET MAY HAVE SOME FREEZING DRIZZLE CONCERNS WHICH COULD CAUSE
SLICK/ICY ROADS. MOST LOW TEMPERATURES IN FORECAST FOR CWA ARE
EXPECTED TO REMAIN ABOVE FREEZING SO THIS IS NOT EXPECTED TO BE AN
ISSUE...BUT WILL BE CLOSELY MONITORED REGARDLESS FOR POTENTIAL
NEED FOR UPDATES AND/OR STATEMENTS.
PREVIOUS DISCUSSION FOLLOWS...
TONIGHT AN UPPER LOW WILL MOVE INTO THE AREA AND PROVIDE SOME
ADDITIONAL FORCING. MAV MOS GIVES VERY LOW POPS WHILE MET MOS IS
PRETTY HIGH. REALITY WILL LIKELY BE IN BETWEEN.
MOISTURE BECOMES LIMITED TO THE LOWER LAYERS OF THE ATMOSPHERE
PRETTY QUICKLY...SO THERE IS SOME QUESTION WHETHER ICE WILL BE
INTRODUCED INTO THE CLOUD. TIME SECTIONS SHOW THAT IT WILL BE
CLOSE...SO WILL KEEP MENTION OF DRIZZLE AND RAIN/SNOW THROUGH THE
NIGHT.
PRECIPITATION WILL BE LIQUID THROUGH THE EVENING...BUT TEMPERATURES
COOL FROM NORTHWEST TO SOUTHEAST TONIGHT MAKING ANY PRECIPITATION
/ASIDE FROM THE DRIZZLE/ SNOW.
WENT NEAR MAV MOS MOST AREAS FOR LOWS TONIGHT. THIS KEEPS
TEMPERATURES ABOVE FREEZING FOR MOST OF THE AREA FOR THE VAST
MAJORITY OF THE NIGHT.
THUS WHILE CANNOT ABSOLUTELY RULE OUT FREEZING DRIZZLE AT THIS
TIME...FEEL THAT COVERAGE AND LENGTH OF ANY THAT DOES APPEAR IS TOO
LOW TO MENTION AT THIS TIME. WILL KEEP MENTION OF SLICK SPOTS EARLY
IN THE MORNING IN THE HAZARDOUS WEATHER OUTLOOK TO ACCOUNT FOR
BRIDGES/OVERPASSES/UNTREATED SURFACES.
&&
.SHORT TERM.../TUESDAY THROUGH THURSDAY/
ISSUED AT 222 PM EST MON DEC 8 2014
FOCUS IS ON ANY CHANCES FOR PRECIPITATION TUESDAY THEN ON SKY COVER.
MODELS ARE CLOSE ENOUGH THAT A BLEND WAS USED.
EXITING UPPER SYSTEM AND CYCLONIC FLOW WILL KEEP CLOUDY SKIES ON
TUESDAY AND COULD ALSO HELP PRODUCE SOME LIGHT
PRECIPITATION...ESPECIALLY IF SOME LAKE ENHANCEMENT OCCURS ACROSS
THE NORTHEAST. PROBLEM REMAINS LACK OF DEEP MOISTURE AND POTENTIAL
LACK OF ICE IN THE CLOUDS.
WITH THE UNCERTAINTY IN PRECIPITATION TYPE DECIDED TO KEEP MENTION
OF DRIZZLE AND SNOW WITH LOW POPS MOST AREAS. AS NOTED IN THE NEAR
TERM CANNOT ABSOLUTELY RULE OUT A BRIEF PERIOD OF FREEZING DRIZZLE
SOME AREAS VERY EARLY TUESDAY...BUT NOT CONFIDENT ENOUGH TO MENTION
AT THIS TIME.
TUESDAY NIGHT FORCING ENDS SO DO NOT EXPECT PRECIPITATION. HIGH
PRESSURE TRIES TO BUILD IN FROM THE WEST...BUT STRONG SYSTEM ACROSS
THE NORTHEASTERN USA KEEPS THE AREA IN CYCLONIC FLOW. THUS EXPECT
PLENTY OF CLOUDS ACROSS THE AREA.
THE CLOUDS WILL LINGER INTO WEDNESDAY...ESPECIALLY EAST WITH THE
AFOREMENTIONED STRONG SYSTEM. HIGH PRESSURE SHOULD GAIN MORE
INFLUENCE WEDNESDAY NIGHT INTO THURSDAY...SO ALLOWED FOR PARTLY
CLOUDY CONDITIONS ALL AREAS THEN.
FOR TEMPERATURES...WENT BELOW MOS FOR HIGHS TUESDAY GIVEN EXPECTED
CLOUD COVER. CUT SOME ON WEDNESDAY AS WELL WITH EXPECTED SKY COVER.
OTHERWISE GENERALLY STUCK WITH A MODEL BLEND.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
ISSUED AT 257 PM EST MON DEC 8 2014
MODELS IN GOOD AGREEMENT THAT A BROAD AREA OF SURFACE HIGH PRESSURE
ALONG WITH A DRY ATMOSPHERIC COLUMN WILL RESULT IN ABOVE NORMAL
TEMPERATURES AND DRY WEATHER THROUGH THE WEEKEND. MEANWHILE...THE
OPERATIONAL 12Z GFS AND ECMWF ARE HAVING DIFFICULTIES COMING
TOGETHER FOR DAY 7 WITH THE GFS QUICKER WITH SEPARATE UPPER
LOWS...IN SPLIT FLOW...ACROSS THE UPPER AND LOWER MISSISSIPPI
VALLEYS. DESPITE BEING QUICKER WITH THESE SYSTEMS...THE GFS WAS
SLOWER WITH THE QPF THAN THE EURO. WITH THE GFS TYPICAL TOO FAST AND
THE EURO TO STRONG WITH STRONGER SYSTEMS IN SPLIT FLOW...WILL ACCEPT
THE REGIONAL BLEND WHICH HOLDS OFF RAIN CHANCES TIL MONDAY.
00Z DECEMBER 8 ECM MOS HIGHS CLOSE TO REGIONAL BLEND AND LOOK GOOD
WITH ABOVE AVERAGE HIGHS IN THE 40S AND PERHAPS EVEN 50S BY SUNDAY.
THIS ALSO MATCHES UP NICELY WITH THE CLIMATE PREDICTION CENTER 6 TO
10 DAY OUTLOOK WHICH STRONGLY FAVORS ABOVE NORMAL TEMPERATURES FOR
THE EXTENDED.
&&
.AVIATION /DISCUSSION FOR THE 090600Z TAFS/...
ISSUED AT 1140 PM EST MON DEC 8 2014
APPEARS COLD FRONT WILL BE IN THE PROCESS OF PASSING OFF TO THE EAST
OF KIND/KBMG NEAR TO SHORTLY AFTER ISSUANCE TIME. MUCH OF THE POST
FRONTAL IFR CEILINGS HAVE DISSIPATED...ALTHOUGH EXTENSIVE MVFR DECK
AROUND 015 EXTENDS WELL UPSTREAM INTO THE NORTHERN MIDWEST. THERE
MAY BE A BRIEF PERIOD WHERE THE MVFR CEILINGS SCATTER OUT IN THE
IMMEDIATE POST FRONTAL ZONE...BUT FOR THE MOST PART EXPECTING
CEILINGS AROUND 015...LINGERING BEYOND 091800Z.
SOME LIGHT SNOW BEGINNING TO SHOW UP OVER PARTS OF SOUTHERN
WISCONSIN AND NORTHERN ILLINOIS UNDER THE UPPER LOW. SHORT TERM
MODELS SUGGEST THE UPPER LOW WILL MOVE OVER THE TAF SITES ROUGHLY
091000Z-091600Z...SO THERE MAY BE SOME PERIODS OF LIGHT SNOW DURING
THOSE TIMES. IFR VISIBILITY RESTRICTIONS UNDER THE UPPER SYSTEM HAVE
ONLY BEEN ISOLATED IN NATURE SO FAR...SO WILL KEEP THE VISIBILITY
FORECAST ABOVE IFR FOR NOW.
IN THE WAKE OF THE FRONT...SURFACE WINDS EXPECTED TO SETTLE AROUND
290-310 DEGREES AT 9-13 KTS OVERNIGHT. WINDS MAY VEER A BIT MORE
TOWARDS 320-340 DEGREES BY LATE MORNING WITH SOME GUSTS 18-20 KTS
PROBABLE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...SMF/50
SHORT TERM...50
LONG TERM...KOCH
AVIATION...JAS
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
1143 AM CST TUE DEC 9 2014
.SHORT TERM /TODAY/...
ISSUED AT 301 AM CST TUE DEC 9 2014
CLOUD COVER AND TEMPS WERE THE FOCUS AS THE SURFACE HIGH SLOWLY
BUILDS INTO THE STATE THROUGHOUT THE DAY TODAY. CAA CONTINUES THIS
MORNING AND FINALLY DIMINISHES BY THE EARLY AFTERNOON. LOW LEVEL
MOISTURE LOOKS TO POTENTIALLY REMAIN TRAPPED UNDER THE INVERSION
SETTING UP AROUND 925M THROUGH THE DAY. THIS WOULD SUGGEST LOW
STRATUS DECK TO LINGER INTO THE AFTERNOON AND INCREASED SKY COVER
DURING THIS TIME TO REFLECT THIS TREND. THE 09.06Z HRRR AND 09.03Z
HOPWRF HINTING ON CLOUD COVER LASTING THROUGH THE AFTERNOON HOURS
TODAY AS WELL. TEMPS SHOULD STRUGGLE TO INCREASE MUCH TODAY WITH
THE STRATUS AND CAA PERSISTING FOR MUCH OF THE DAY. LOWERED MAX
TEMPS ACROSS THE NORTH AND WEST A DEGREE BUT LEFT THE REMAINDER OF
THE FORECAST WITH PREVIOUS FORECAST AS IT LOOKED ON TRACK.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 301 AM CST TUE DEC 9 2014
OVERALL...THE MID TO LATE WEEK PATTERN WILL FEATURE A PERIOD OF
INCREASED WARMING AND MOISTURE. SUBJECTIVE H850 ANALYSIS TONIGHT
SHOWS UPPER LEVEL LOW AND COLD AIR ADVECTION OVER THE REGION...WITH
THE GREAT LAKES WAVE SUPPRESSING MOISTURE TO THE FAR SOUTHERN
STATES. HIGH PRESSURE ALOFT OVER THE SOUTHERN PLAINS IS ALREADY
SUPPORTING RETURN FLOW OVER THE RED RIVER VALLEY INTO NEW MEXICO.
MODELS SHOW THAT THIS PLUME WILL GRADUALLY MOVE NORTHWEST THEN
NORTHEAST INTO THE CENTRAL PLAINS BY MID TO LATE WEEK...AND THROUGH
THE WEEKEND. THOUGH THE PATTERN REMAINS FAIRLY QUIET INTO THE EARLY
WEEKEND...THE RETURN OF MOISTURE AND LOW STRATUS ALONG WITH DRIZZLE
OR LIGHT RAIN POTENTIAL WILL BE THE MAIN CHALLENGES IN THE NEXT 5
DAYS. FOR TONIGHT...A WEAK WAVE CURRENTLY OVER MONTANA WILL DROP
SOUTHEAST INTO THE NORTHWEST FLOW AND BRING WITH IT ANOTHER AREA OF
MID LEVEL CLOUDS TO THE REGION LATE THIS EVENING AND OVERNIGHT. WEAK
WARM AIR ADVECTION WILL ACCOMPANY THE SYSTEM...ALLOWING TEMPERATURES
OVERNIGHT TO REMAIN SIMILAR TO EARLY THIS MORNINGS LOWS. CLOUDS
WILL PASS THROUGH THE AREA AGAIN WEDNESDAY NIGHT AND THURSDAY WITH
CONTINUED WARM AIR ADVECTION AND MOISTURE ADVECTION ON THE BACK
SIDE OF THE RIDGE. ONCE AGAIN WITH TONIGHTS RUN...THE NAM IS
FASTER WITH SATURATION AT LOWER LEVELS WHILE THE GFS INITIALLY WED
NIGHT AND THURSDAY MORNING DOES NOT SHOW SATURATION...BUT LATER IN
THE DAY THURSDAY INTO THURSDAY NIGHT/FRIDAY. HAVE OPTED TO
MAINTAIN A DRY FORECAST FOR NOW. BUFR SOUNDINGS SHOW MORE
WIDESPREAD CLOUDS THURSDAY INTO FRIDAY...WHICH MAY IMPACT MINS AND
ESPECIALLY HIGHS BOTH DAYS. FOR NOW...HAVE TRIMMED FRI HIGHS A BIT
OVER THE AREA BACK DOWN INTO THE MID TO UPPER 40S CENTRAL TO LOWER
50S WEST/SOUTH. BY SATURDAY SOUTHWEST FLOW WILL PERSIST ACROSS THE
ENTIRE REGION WITH READINGS INTO THE LOWER TO MID 50S OVER MOST OF
THE SOUTH...UPPER 40S NORTHEAST. STRATUS WILL STILL BE PREVALENT
ACROSS THE AREA...BUT MIXING MIGHT PROMOTE SOME BREAKS IN CLOUD
COVER. DIFFUSE WARM AIR ADVECTION ALOFT MAY BE ENOUGH TO PRODUCE A
FEW LIGHT SHOWERS AS WELL...ESPECIALLY LATER IN THE AFTERNOON WEST
INTO SATURDAY NIGHT. MODELS CONTINUE TO SHOW A MORE PRONOUNCED
WAVE BY DAYS 6 AND 7 WITH A LEE SIDE TROUGH DEEPENING OVER THE
SOUTHERN PLAINS. THE MODELS STILL DIVERGE ON SOLUTIONS WITH THE
GFS FARTHER NORTH AND PHASING THE TWO STREAMS WHILE THE EURO IS
MORE PROGRESSIVE BUT DOES ALSO ALLOW FOR A RAIN SNOW MIX BY
MONDAY. GIVEN THE UNCERTAINTY...WILL MAINTAIN A BLENDED APPROACH
UNTIL DETAILS BECOME MORE APPARENT. AFTER A MILD WEEKEND...PASSAGE
OF SYSTEM MONDAY WILL USHER IN COOLER TEMPERATURES FOR EARLY NEXT
WEEK.
&&
.AVIATION...09/18Z
ISSUED AT 1142 AM CST TUE DEC 9 2014
A LARGE REGION OF IFR TO MVFR STRATUS BLANKETS MUCH OF THE UPPER
MIDWEST THIS AFTERNOON. A FEW CLEARING SPOTS HAVE DEVELOPED OVER
EASTERN IOWA INTO SRN WISCONSIN. SEVERAL OF THE CLEARING PATCHES
ARE NEAR SITES HOWEVER AS THE STEERING FLOW SWITCHES FROM THE
NORTH TO SOUTHEAST...THE STRATUS WILL SLOW TO STALL FOR A PERIOD.
THIS WILL LEAVE SITES ON THE EDGE WITH PERIODS OF REDUCED
CEILINGS AND LESSER PERIODS WITH VFR. THE STATUS SHOULD BECOME
MORE EXPANSIVE AGAIN TONIGHT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
536 AM CST TUE DEC 9 2014
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
ISSUED AT 301 AM CST TUE DEC 9 2014
CLOUD COVER AND TEMPS WERE THE FOCUS AS THE SURFACE HIGH SLOWLY
BUILDS INTO THE STATE THROUGHOUT THE DAY TODAY. CAA CONTINUES THIS
MORNING AND FINALLY DIMINISHES BY THE EARLY AFTERNOON. LOW LEVEL
MOISTURE LOOKS TO POTENTIALLY REMAIN TRAPPED UNDER THE INVERSION
SETTING UP AROUND 925M THROUGH THE DAY. THIS WOULD SUGGEST LOW
STRATUS DECK TO LINGER INTO THE AFTERNOON AND INCREASED SKY COVER
DURING THIS TIME TO REFLECT THIS TREND. THE 09.06Z HRRR AND 09.03Z
HOPWRF HINTING ON CLOUD COVER LASTING THROUGH THE AFTERNOON HOURS
TODAY AS WELL. TEMPS SHOULD STRUGGLE TO INCREASE MUCH TODAY WITH
THE STRATUS AND CAA PERSISTING FOR MUCH OF THE DAY. LOWERED MAX
TEMPS ACROSS THE NORTH AND WEST A DEGREE BUT LEFT THE REMAINDER OF
THE FORECAST WITH PREVIOUS FORECAST AS IT LOOKED ON TRACK.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 301 AM CST TUE DEC 9 2014
OVERALL...THE MID TO LATE WEEK PATTERN WILL FEATURE A PERIOD OF
INCREASED WARMING AND MOISTURE. SUBJECTIVE H850 ANALYSIS TONIGHT
SHOWS UPPER LEVEL LOW AND COLD AIR ADVECTION OVER THE REGION...WITH
THE GREAT LAKES WAVE SUPPRESSING MOISTURE TO THE FAR SOUTHERN
STATES. HIGH PRESSURE ALOFT OVER THE SOUTHERN PLAINS IS ALREADY
SUPPORTING RETURN FLOW OVER THE RED RIVER VALLEY INTO NEW MEXICO.
MODELS SHOW THAT THIS PLUME WILL GRADUALLY MOVE NORTHWEST THEN
NORTHEAST INTO THE CENTRAL PLAINS BY MID TO LATE WEEK...AND THROUGH
THE WEEKEND. THOUGH THE PATTERN REMAINS FAIRLY QUIET INTO THE EARLY
WEEKEND...THE RETURN OF MOISTURE AND LOW STRATUS ALONG WITH DRIZZLE
OR LIGHT RAIN POTENTIAL WILL BE THE MAIN CHALLENGES IN THE NEXT 5
DAYS. FOR TONIGHT...A WEAK WAVE CURRENTLY OVER MONTANA WILL DROP
SOUTHEAST INTO THE NORTHWEST FLOW AND BRING WITH IT ANOTHER AREA OF
MID LEVEL CLOUDS TO THE REGION LATE THIS EVENING AND OVERNIGHT. WEAK
WARM AIR ADVECTION WILL ACCOMPANY THE SYSTEM...ALLOWING TEMPERATURES
OVERNIGHT TO REMAIN SIMILAR TO EARLY THIS MORNINGS LOWS. CLOUDS
WILL PASS THROUGH THE AREA AGAIN WEDNESDAY NIGHT AND THURSDAY WITH
CONTINUED WARM AIR ADVECTION AND MOISTURE ADVECTION ON THE BACK
SIDE OF THE RIDGE. ONCE AGAIN WITH TONIGHTS RUN...THE NAM IS
FASTER WITH SATURATION AT LOWER LEVELS WHILE THE GFS INITIALLY WED
NIGHT AND THURSDAY MORNING DOES NOT SHOW SATURATION...BUT LATER IN
THE DAY THURSDAY INTO THURSDAY NIGHT/FRIDAY. HAVE OPTED TO
MAINTAIN A DRY FORECAST FOR NOW. BUFR SOUNDINGS SHOW MORE
WIDESPREAD CLOUDS THURSDAY INTO FRIDAY...WHICH MAY IMPACT MINS AND
ESPECIALLY HIGHS BOTH DAYS. FOR NOW...HAVE TRIMMED FRI HIGHS A BIT
OVER THE AREA BACK DOWN INTO THE MID TO UPPER 40S CENTRAL TO LOWER
50S WEST/SOUTH. BY SATURDAY SOUTHWEST FLOW WILL PERSIST ACROSS THE
ENTIRE REGION WITH READINGS INTO THE LOWER TO MID 50S OVER MOST OF
THE SOUTH...UPPER 40S NORTHEAST. STRATUS WILL STILL BE PREVALENT
ACROSS THE AREA...BUT MIXING MIGHT PROMOTE SOME BREAKS IN CLOUD
COVER. DIFFUSE WARM AIR ADVECTION ALOFT MAY BE ENOUGH TO PRODUCE A
FEW LIGHT SHOWERS AS WELL...ESPECIALLY LATER IN THE AFTERNOON WEST
INTO SATURDAY NIGHT. MODELS CONTINUE TO SHOW A MORE PRONOUNCED
WAVE BY DAYS 6 AND 7 WITH A LEE SIDE TROUGH DEEPENING OVER THE
SOUTHERN PLAINS. THE MODELS STILL DIVERGE ON SOLUTIONS WITH THE
GFS FARTHER NORTH AND PHASING THE TWO STREAMS WHILE THE EURO IS
MORE PROGRESSIVE BUT DOES ALSO ALLOW FOR A RAIN SNOW MIX BY
MONDAY. GIVEN THE UNCERTAINTY...WILL MAINTAIN A BLENDED APPROACH
UNTIL DETAILS BECOME MORE APPARENT. AFTER A MILD WEEKEND...PASSAGE
OF SYSTEM MONDAY WILL USHER IN COOLER TEMPERATURES FOR EARLY NEXT
WEEK.
&&
.AVIATION...09/12Z
ISSUED AT 533 AM CST TUE DEC 9 2014
MVFR STRATUS WILL PERSIST THROUGH MUCH OF THE DAY TODAY AND INTO
TONIGHT. LOW CONFIDENCE WITH THE STRATUS BREAKING UP ANYTIME TODAY
AND KEPT MENTION OF IT THROUGH ENTIRE TAF PERIOD. THE LOW LEVEL
MOISTURE TRAPPED UNDER THE INVERSION IS FAIRLY SHALLOW...SO IT
SHOULD BE A THIN ENOUGH TO SEE SUN SHINNING THROUGH.
OTHERWISE...POSSIBLE FOG DEVELOPING TOWARDS WEDNESDAY MORNING BUT
LEFT OUT MENTION ATTM TIME DUE TO UNCERTAINTY OF STRATUS
DEPARTURE. HOPWRF/HRRR LATEST MODEL RUNS KEEP THE STRATUS
THROUGHOUT THE AFTERNOON TODAY. THERE IS A COUPLE OF VFR HOLES IN
THE STRATUS DECK...BUT SHOULD QUICKLY FILL BACK IN WITH THE CAA.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
304 AM CST TUE DEC 9 2014
.SHORT TERM /TODAY/...
ISSUED AT 301 AM CST TUE DEC 9 2014
CLOUD COVER AND TEMPS WERE THE FOCUS AS THE SURFACE HIGH SLOWLY
BUILDS INTO THE STATE THROUGHOUT THE DAY TODAY. CAA CONTINUES THIS
MORNING AND FINALLY DIMINISHES BY THE EARLY AFTERNOON. LOW LEVEL
MOISTURE LOOKS TO POTENTIALLY REMAIN TRAPPED UNDER THE INVERSION
SETTING UP AROUND 925M THROUGH THE DAY. THIS WOULD SUGGEST LOW
STRATUS DECK TO LINGER INTO THE AFTERNOON AND INCREASED SKY COVER
DURING THIS TIME TO REFLECT THIS TREND. THE 09.06Z HRRR AND 09.03Z
HOPWRF HINTING ON CLOUD COVER LASTING THROUGH THE AFTERNOON HOURS
TODAY AS WELL. TEMPS SHOULD STRUGGLE TO INCREASE MUCH TODAY WITH
THE STRATUS AND CAA PERSISTING FOR MUCH OF THE DAY. LOWERED MAX
TEMPS ACROSS THE NORTH AND WEST A DEGREE BUT LEFT THE REMAINDER OF
THE FORECAST WITH PREVIOUS FORECAST AS IT LOOKED ON TRACK.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 301 AM CST TUE DEC 9 2014
OVERALL...THE MID TO LATE WEEK PATTERN WILL FEATURE A PERIOD OF
INCREASED WARMING AND MOISTURE. SUBJECTIVE H850 ANALYSIS TONIGHT
SHOWS UPPER LEVEL LOW AND COLD AIR ADVECTION OVER THE REGION...WITH
THE GREAT LAKES WAVE SUPPRESSING MOISTURE TO THE FAR SOUTHERN
STATES. HIGH PRESSURE ALOFT OVER THE SOUTHERN PLAINS IS ALREADY
SUPPORTING RETURN FLOW OVER THE RED RIVER VALLEY INTO NEW MEXICO.
MODELS SHOW THAT THIS PLUME WILL GRADUALLY MOVE NORTHWEST THEN
NORTHEAST INTO THE CENTRAL PLAINS BY MID TO LATE WEEK...AND THROUGH
THE WEEKEND. THOUGH THE PATTERN REMAINS FAIRLY QUIET INTO THE EARLY
WEEKEND...THE RETURN OF MOISTURE AND LOW STRATUS ALONG WITH DRIZZLE
OR LIGHT RAIN POTENTIAL WILL BE THE MAIN CHALLENGES IN THE NEXT 5
DAYS. FOR TONIGHT...A WEAK WAVE CURRENTLY OVER MONTANA WILL DROP
SOUTHEAST INTO THE NORTHWEST FLOW AND BRING WITH IT ANOTHER AREA OF
MID LEVEL CLOUDS TO THE REGION LATE THIS EVENING AND OVERNIGHT. WEAK
WARM AIR ADVECTION WILL ACCOMPANY THE SYSTEM...ALLOWING TEMPERATURES
OVERNIGHT TO REMAIN SIMILAR TO EARLY THIS MORNINGS LOWS. CLOUDS
WILL PASS THROUGH THE AREA AGAIN WEDNESDAY NIGHT AND THURSDAY WITH
CONTINUED WARM AIR ADVECTION AND MOISTURE ADVECTION ON THE BACK
SIDE OF THE RIDGE. ONCE AGAIN WITH TONIGHTS RUN...THE NAM IS
FASTER WITH SATURATION AT LOWER LEVELS WHILE THE GFS INITIALLY WED
NIGHT AND THURSDAY MORNING DOES NOT SHOW SATURATION...BUT LATER IN
THE DAY THURSDAY INTO THURSDAY NIGHT/FRIDAY. HAVE OPTED TO
MAINTAIN A DRY FORECAST FOR NOW. BUFR SOUNDINGS SHOW MORE
WIDESPREAD CLOUDS THURSDAY INTO FRIDAY...WHICH MAY IMPACT MINS AND
ESPECIALLY HIGHS BOTH DAYS. FOR NOW...HAVE TRIMMED FRI HIGHS A BIT
OVER THE AREA BACK DOWN INTO THE MID TO UPPER 40S CENTRAL TO LOWER
50S WEST/SOUTH. BY SATURDAY SOUTHWEST FLOW WILL PERSIST ACROSS THE
ENTIRE REGION WITH READINGS INTO THE LOWER TO MID 50S OVER MOST OF
THE SOUTH...UPPER 40S NORTHEAST. STRATUS WILL STILL BE PREVALENT
ACROSS THE AREA...BUT MIXING MIGHT PROMOTE SOME BREAKS IN CLOUD
COVER. DIFFUSE WARM AIR ADVECTION ALOFT MAY BE ENOUGH TO PRODUCE A
FEW LIGHT SHOWERS AS WELL...ESPECIALLY LATER IN THE AFTERNOON WEST
INTO SATURDAY NIGHT. MODELS CONTINUE TO SHOW A MORE PRONOUNCED
WAVE BY DAYS 6 AND 7 WITH A LEE SIDE TROUGH DEEPENING OVER THE
SOUTHERN PLAINS. THE MODELS STILL DIVERGE ON SOLUTIONS WITH THE
GFS FARTHER NORTH AND PHASING THE TWO STREAMS WHILE THE EURO IS
MORE PROGRESSIVE BUT DOES ALSO ALLOW FOR A RAIN SNOW MIX BY
MONDAY. GIVEN THE UNCERTAINTY...WILL MAINTAIN A BLENDED APPROACH
UNTIL DETAILS BECOME MORE APPARENT. AFTER A MILD WEEKEND...PASSAGE
OF SYSTEM MONDAY WILL USHER IN COOLER TEMPERATURES FOR EARLY NEXT
WEEK.
&&
.AVIATION...09/06Z
ISSUED AT 1102 PM CST MON DEC 8 2014
LOW STRATUS CONTINUES TO BE IN PLACE ACROSS THE CWA WITH A FEW
HOLES EVERY NOW AND THEN. OVERALL CIGS IN THE MVFR RANGE AROUND
BKN015-025...BUT A FEW SPOTS IN THE LOW VFR RANGE AS WELL. LOOKS
LIKE LOW CIGS TO REMAIN THROUGH THE NIGHT AND INTO TUESDAY BEFORE
BREAKING UP SOME DURING THE DAY. HOWEVER MOISTURE PLOTS ADVERTISE
THEM REFORMING IN THE EVENING WITH SOUTHERLY FLOW AND MOISTURE
PUSHING BACK INTO THE CWA. THEREFORE HAVE ADVERTISED WITH A SCT
DECK ATTM SINCE UNCERTAINTY IS HIGH. NORTHWEST WINDS TO BECOME
MORE NORTHERLY THROUGH THE PERIOD AND THEN SHIFT AROUND TO THE
EAST SOUTHEAST LATE TUESDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...BEERENDS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
249 PM CST Tue Dec 9 2014
.SHORT TERM...(This Evening through Wednesday)
Issued at 227 PM CST TUE DEC 9 2014
Surface high pressure continues to build southward today ahead of
the next weak shortwave, which will drop southeastward within the
northwest flow aloft. Meanwhile the edge of the stratus deck has
worked into far northeast KS this morning. The NAM and GFS forecast
has kept this stratus from building further into the forecast area
later this evening. The latest HRRR and RAP have now developed the
stratus further southward towards the I-70 corridor. It appears that
the models are cooling that near saturated layer once daytime mixing
has stopped. Across central KS with the exception of some high
clouds mostly clear skies may allow the boundary layer to cool
enough for fog. Although the soundings seem to indicate relatively
strong winds just above the surface, which may prevent this from
developing. If the stratus develops and or continues in the
northeast areas then the forecast lows will probably be too cool.
Otherwise most areas should drop into the mid to upper 20s.
With regards to precipitation early tomorrow morning. The models
have been trending much drier in the lower levels as the lift
increases in the saturated layers. The lift appears to be fairly
weak and only efficient for drizzle, but with the dry air in place
that drizzle will most likely not reach the ground. Temperatures are
also forecast to gradually rise tomorrow morning reaching above
freezing by late morning or around noon. So freezing precipitation
is looking unlikely at this point. Temperatures will warm as the
winds veer on the back side of the retreating surface high. There is
also an outside chance that if the lift is strong enough to generate
rain then sprinkles will be possible as advertised by the ECMWF and
GEM. This would most likely occur during the afternoon hours when
the wave is forecast to pass over the area. High temperatures
tomorrow should reach the around 40 for most locations.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 227 PM CST TUE DEC 9 2014
The long term forecast remains cloudy and dreary for the most
part with the bulk of the forecast focus on an impending large
storm system which should arrive by late Sunday into early next
week.
For Wednesday night through Saturday, the forecast area will be
entrenched in a very moist near-surface airmass. While there will
be ridging overhead, it appears that this will only help to keep
the surface airmass fairly stagnant through Friday and expect the
persistent low clouds to keep temperatures pretty well in check
with minimal diurnal temperature swings. There will also be
periods of drizzle and fog...particularly overnight and into the
morning hours...with weak but persistent lift within the moist
layer. The good news is that even with the clouds, temperatures
will be above freezing through Saturday night and any light
precipitation will fall as liquid. Also, as the weak progresses,
southerly low level winds will also advect warmer temperatures
into the area to the extent that even without sunshine the area
should be in the upper 50s to around 60 for high temperatures
Friday through Sunday.
Late Saturday into Sunday, a large storm system will be taking
shape over the western CONUS, and is scheduled to bring
precipitation into the local forecast area by late Sunday. While
model guidance is currently in rather strong agreement regarding
the evolution of this system, forecaster confidence remains toward
the low end. The reason for this low confidence lies in the
complex nature of the storm and also the run-to-run model
variability over the past few days. The main energy to impact the
local area will come from the southwestern CONUS, but will also
interact (unsure how much) with a strong northern stream short
wave trough. This interaction will strongly impact the atmospheric
temperature profiles on the north and northwest side of the storm
system and could have a profound impact on the local weather for
Sunday night into Monday night. One thing that is certain is that
this storm system will not lack moisture as it will have a strong
moisture feed ahead of it for several days into the Plains.
Current indications are that this event would be mainly rain for
the local area with some amounts greater than 1", but could mix
with snow or other winter weather types especially across north
central KS late in the event. The wild card is in how cold the
airmass is behind an incoming cold front that will undercut the
system. Lower resolution models can sometimes trend a bit too warm
with undercutting cold airmasses in the long range, but lack of
snow cover to the north supports a slightly warmer airmass. If
it should trend colder there would be more of a chance for winter
precip locally.
&&
.AVIATION...(For the 18Z TAFs through 18Z Wednesday Afternoon)
Issued at 1148 AM CST TUE DEC 9 2014
The progression of the MVFR ceilings have stopped just northeast
of TOP/FOE. The tafs appear to stay VFR through the taf period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...Barjenbruch
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1144 AM CST TUE DEC 9 2014
...UPDATED FOR AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 225 AM CST TUE DEC 9 2014
HIGH LEVEL CLOUD COVER WILL BE LIKELY TODAY ACROSS THE CENTRAL
HIGH PLAINS AS A COLD FRONT STALLS OUT IN EXTREME SOUTHWEST KANSAS
BY LATE MORNING. CONFIDENCE IS NOT HIGH ON HOW DENSE THESE CLOUDS
WILL BE BUT NAM, GFS, AND RAP ALL INDICATE A COOLING TREND IN THE
925MB TO 850MB LEVEL FROM 00Z TUESDAY TO 00Z WEDNESDAY. GIVEN THIS
COOLING TREND, MORE CLOUDS TODAY COMPARED TO YESTERDAY, AND AN
EASTERLY WIND WILL STAY CLOSE TO THE PREVIOUS FORECAST FOR HIGHS
THIS AFTERNOON. TEMPERATURES CLIMBING INTO THE UPPER 50S TO NEAR
60 STILL LOOKS REASONABLE IN EXTREME SOUTHWEST KANSAS WHICH WILL
BE NEAR/SOUTH OF THE COLD FRONT WHILE HIGHS ONLY IN THE MID 40S IN
NORTH CENTRAL KANSAS. EXACTLY HOW THE GRADIENT WILL END UP BETWEEN
THESE TWO EXTREMES IS UNCLEAR.
ISENTROPIC AND MOISTURE ADVECTION WILL IMPROVE ACROSS WESTERN
KANSAS IN THE 900MB TO 800MB LEVEL. STRATUS ALONG WITH POSSIBLY
SOME AREAS OF FOG APPEARING LIKELY AS THE LOWER LEVELS SATURATE
OVERNIGHT. DEPTH OF THIS MOIST LAYER WILL BE IN THE 2000 TO 3000
FT AGL RANGE DEPENDING ON WHICH MODEL SOUNDING YOU EXAMINE. GIVEN
THE DEPTH OF THIS LAYER AM TRENDING AWAY FROM INTRODUCING DRIZZLE
LATE TONIGHT BUT IF THE NAM ENDS UP BEING MORE CORRECT THEN SOME
PATCHY DRIZZLE COULD DEVELOP TOWARDS DAYBREAK. TEMPERATURES ARE
EXPECTED TO FALL TO AROUND 32 DEGREES BUT GIVEN THE INCREASE IN
LOW LEVEL MOISTURE FORECAST OVERNIGHT THE LOWS MAY OCCUR EARLY
WITH TEMPERATURES THEN HOLDING NEARLY STEADY OR EVEN RISE A FEW
DEGREES AFTER MIDNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CST TUE DEC 9 2014
THE PERIOD BETWEEN WEDNESDAY AND SATURDAY WILL BE A TRUE CHALLENGE
WITH RESPECT TO SKY COVER AND RESULTING TEMPERATURES BOTH IN THE
DAYTIME FOR HIGHS AS WELL AS LOWS OVERNIGHT. RELATIVELY MORE MOIST
CONDITIONS IN THE BOUNDARY LAYER MARKED BY DEW POINTS IN THE UPPER
30S AND 40S COULD CONTRIBUTE TO EVENING/NIGHT FOG DEVELOPMENT IN
ADDITION TO ALREADY EXPECTED STRATUS. STRATUS THAT DOES ERODE
DURING THE DAY SHOULD BE ABLE RAPIDLY REDEVELOP ACROSS MUCH OF
CENTRAL KANSAS INTO THE EVENING AS THE BOUNDARY LAYER COOLS
DIURNALLY. MODELS SOUNDINGS GENERALLY LIMIT THE THICKNESS TO
SLIGHTLY MORE THAN 2000 FT, WHICH IS NOT FAVORABLE FOR DRIZZLE
DESPITE MODEL QPF OUTPUT. THE PRIMARY CHALLENGE WILL BE
DETERMINING HOW FAR WEST THE STRATUS IMPACTS THE FORECAST AREA
EACH DAY AND IT`S EFFECT ON TEMPERATURES. WEDNESDAY INTO THURSDAY
NIGHT APPEARS LIKELY TO BRING THE MOST WIDESPREAD OVERCAST
CONDITIONS, WHILE THE WESTERN MOST COUNTIES, GENERALLY WEST OF
HIGHWAY 83 WILL EXPERIENCE THE MOST HOURS OF INSOLATION AND CLEAR
SKIES DURING THIS TIMEFRAME.
UNLESS THE MODELS SIGNIFICANTLY DIVERGE IN SOLUTIONS FROM THE
CURRENT AND RECENT RUNS, SUNDAY NIGHT (OR AROUND THAT SYNOPTIC
TIMESCALE/TIMEFRAME) LOOKS WET WITH RAIN POTENTIAL OR EVEN SNOW
WITH AS UPPER DYNAMIC LOW PRESSURE MOVING THROUGH OR JUST SOUTH OF
THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1136 AM CST TUE DEC 9 2014
AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS INTO EASTERN KANSAS
TONIGHT, SURFACE WINDS WILL BECOME SOUTHEASTERLY UPSLOPE AROUND
8-10KT ACROSS WESTERN KANSAS. SOME IFR/LIFR CONDITIONS ARE
POSSIBLE BY 11-13Z ACROSS MUCH OF WESTERN KANSAS WITH LIGHT
FREEZING FOG AND LOW CIGS. LOW CONDITIONS WILL GRADUALLY IMPROVE
BY 16-18Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 49 33 47 41 / 0 10 10 10
GCK 52 31 50 37 / 0 10 0 0
EHA 59 34 57 35 / 0 0 0 0
LBL 56 36 56 44 / 0 10 0 0
HYS 42 29 43 38 / 0 10 10 10
P28 49 31 46 41 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
654 AM CST TUE DEC 9 2014
...UPDATED AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 225 AM CST TUE DEC 9 2014
HIGH LEVEL CLOUD COVER WILL BE LIKELY TODAY ACROSS THE CENTRAL
HIGH PLAINS AS A COLD FRONT STALLS OUT IN EXTREME SOUTHWEST KANSAS
BY LATE MORNING. CONFIDENCE IS NOT HIGH ON HOW DENSE THESE CLOUDS
WILL BE BUT NAM, GFS, AND RAP ALL INDICATE A COOLING TREND IN THE
925MB TO 850MB LEVEL FROM 00Z TUESDAY TO 00Z WEDNESDAY. GIVEN THIS
COOLING TREND, MORE CLOUDS TODAY COMPARED TO YESTERDAY, AND AN
EASTERLY WIND WILL STAY CLOSE TO THE PREVIOUS FORECAST FOR HIGHS
THIS AFTERNOON. TEMPERATURES CLIMBING INTO THE UPPER 50S TO NEAR
60 STILL LOOKS REASONABLE IN EXTREME SOUTHWEST KANSAS WHICH WILL
BE NEAR/SOUTH OF THE COLD FRONT WHILE HIGHS ONLY IN THE MID 40S IN
NORTH CENTRAL KANSAS. EXACTLY HOW THE GRADIENT WILL END UP BETWEEN
THESE TWO EXTREMES IS UNCLEAR.
ISENTROPIC AND MOISTURE ADVECTION WILL IMPROVE ACROSS WESTERN
KANSAS IN THE 900MB TO 800MB LEVEL. STATUS ALONG WITH POSSIBLY
SOME AREAS OF FOG APPEARING LIKELY AS THE LOWER LEVELS SATURATE
OVERNIGHT. DEPTH OF THIS MOIST LAYER WILL BE IN THE 2000 TO 3000
FT AGL RANGE DEPENDING ON WHICH MODEL SOUNDING YOU EXAMINE. GIVEN
THE DEPTH OF THIS LAYER AM TRENDING AWAY FROM INTRODUCING DRIZZLE
LATE TONIGHT BUT IF THE NAM ENDS UP BEING MORE CORRECT THEN SOME
PATCHY DRIZZLE COULD DEVELOP TOWARDS DAYBREAK. TEMPERATURES ARE
EXPECTED TO FALL TO AROUND 32 DEGREES BUT GIVEN THE INCREASE IN
LOW LEVEL MOISTURE FORECAST OVERNIGHT THE LOWS MAY OCCUR EARLY
WITH TEMPERATURES THEN HOLDING NEARLY STEADY OR EVEN RISE A FEW
DEGREES AFTER MIDNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CST TUE DEC 9 2014
THE PERIOD BETWEEN WEDNESDAY AND SATURDAY WILL BE A TRUE CHALLENGE
WITH RESPECT TO SKY COVER AND RESULTING TEMPERATURES BOTH IN THE
DAYTIME FOR HIGHS AS WELL AS LOWS OVERNIGHT. RELATIVELY MORE MOIST
CONDITIONS IN THE BOUNDARY LAYER MARKED BY DEW POINTS IN THE UPPER
30S AND 40S COULD CONTRIBUTE TO EVENING/NIGHT FOG DEVELOPMENT IN
ADDITION TO ALREADY EXPECTED STRATUS. STRATUS THAT DOES ERODE
DURING THE DAY SHOULD BE ABLE RAPIDLY REDEVELOP ACROSS MUCH OF
CENTRAL KANSAS INTO THE EVENING AS THE BOUNDARY LAYER COOLS
DIURNALLY. MODELS SOUNDINGS GENERALLY LIMIT THE THICKNESS TO
SLIGHTLY MORE THAN 2000 FT, WHICH IS NOT FAVORABLE FOR DRIZZLE
DESPITE MODEL QPF OUTPUT. THE PRIMARY CHALLENGE WILL BE
DETERMINING HOW FAR WEST THE STRATUS IMPACTS THE FORECAST AREA
EACH DAY AND IT`S EFFECT ON TEMPERATURES. WEDNESDAY INTO THURSDAY
NIGHT APPEARS LIKELY TO BRING THE MOST WIDESPREAD OVERCAST
CONDITIONS, WHILE THE WESTERN MOST COUNTIES, GENERALLY WEST OF
HIGHWAY 83 WILL EXPERIENCE THE MOST HOURS OF INSOLATION AND CLEAR
SKIES DURING THIS TIMEFRAME.
UNLESS THE MODELS SIGNIFICANTLY DIVERGE IN SOLUTIONS FROM THE
CURRENT AND RECENT RUNS, SUNDAY NIGHT (OR AROUND THAT SYNOPTIC
TIMESCALE/TIMEFRAME) LOOKS WET WITH RAIN POTENTIAL OR EVEN SNOW
WITH AS UPPER DYNAMIC LOW PRESSURE MOVING THROUGH OR JUST SOUTH OF
THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 649 AM CST TUE DEC 9 2014
RELATIVELY HIGH DEW POINT DEPRESSIONS BEHIND THE SURFACE COLD
FRONT WILL PRECLUDE ANY FOG DEVELOPMENT THIS MORNING, PROMOTING
VFR CATEGORIES AT THE LOCAL TERMINALS. SURFACE WIND WILL VEER
SOUTHERLY THROUGH THE DAY AS SURFACE HIGH PRESSURE OVER THE
NORTHERN PLAINS MOVES INTO THE MISSISSPPI VALLEY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 49 33 47 41 / 0 10 10 10
GCK 52 31 50 37 / 0 10 0 0
EHA 59 34 57 35 / 0 0 0 0
LBL 56 36 56 44 / 0 10 0 0
HYS 42 29 43 38 / 0 10 10 10
P28 49 31 46 41 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
310 AM MST TUE DEC 9 2014
.UPDATE...
ISSUED AT 925 PM MST MON DEC 8 2014
HAVE ISSUED A DENSE FOG ADVISORY FOR AREAS GENERALLY EAST OF A
LINE FROM TRENTON TO BREWSTER TO RUSSELL SPRINGS. 03Z RUC SIMILAR
TO LATEST HRRR OUTPUT AND 00Z NAM BOOSTING CONFIDENCE THAT DENSE
FOG WILL DEVELOP.
UPDATE ISSUED AT 745 PM MST MON DEC 8 2014
UPDATES REQUIRED FOR FIRST AND SECOND PERIODS (TONIGHT AND
TUESDAY) FOCUSING ON ARRIVAL OF POTENTIALLY DENSE FOG AND LOWER
TEMPERATURES THEN PREVIOUSLY FORECAST.
AT 0230Z CIRRUS SHIELD THAT WAS OVER THE AREA MOST OF THE DAY IS
MOVING EAST AND SLOWLY OUT OF THE AREA. AM EXPECTING MORE TO MOVE
IN LATER IN THE EVENING AND THROUGH THE DAY TOMORROW FROM THE
NORTHWEST.
AT THE SFC STRATUS PER SATELLITE OBS AND RUC 900MB RH FORECAST
CURRENTLY OVER NORTHEAST NEBRASKA/SOUTHWEST IOWA. BY 06Z THIS
NARROW CORRIDOR OF STRATUS FORECAST TO POSSIBLY REACH AREAS JUST
TO THE NORTHEAST FROM MCCOOK TO NORTON. AS SFC HIGH CONTINUES TO
BACK INTO THE AREA WITH LIGHT NORTHEAST WINDS STRATUS DECK
EXPECTED TO REACH A TRENTON TO HILL CITY LINE BY 09Z THEN ROUGHLY
A BENKELMAN TO COLBY AND OAKLEY LINE BY 12Z. IN THE TRENTON TO
HILL CITY AND POINTS NORTHEAST AREAS WINDS ARE CALM AND RH NEAR
100 PERCENT. LATEST RUC/HRRR/NAM VISIBILITY FORECASTS ALL SHOWING
DENSE FOG WITH VISIBILITIES 1/4 MILE OR LESS.
NAM EXTRAPOLATION OF SATURATED BOUNDARY LAYER RH PUSHES IT
FURTHER WEST TOWARD THE CO/KS BORDER WITH DENSE FOG CONTINUING
ROUGHLY FROM TRENTON TO HOXIE AND POINTS EAST. HRRR SUGGESTS
FURTHER WEST TOWARD BENKELMAN TO NEAR GOODLAND AND RUSSELL
SPRINGS.
WILL AWAIT THE 03Z RUC/LATEST HRRR BEFORE ZONE UPDATE SENT BUT
HAVE TRENDED TOWARD ABOVE THINKING.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 119 PM MST MON DEC 8 2014
DECENT AFTERNOON ACROSS THE ENTIRE FORECAST AREA...AS THE TRI STATE
REGION IS SEEING TEMPERATURES 15 TO 20 DEGREES ABOVE NORMAL WITH
READINGS WELL INTO THE 50S. THIS IS ONGOING DESPITE HIGH CLOUDS
MOVING OVER THE AREA CREATING SUNNY CONDITIONS.
HIGH CLOUD COVER WILL SCATTER OUT DURING THE EARLY EVENING HOURS IN
TIME FOR 925MB THERMAL BOUNDARY/SURFACE RIDGE AXIS COMBO...WHICH
MODELS BRING OVER THE REGION BY MIDNIGHT TONIGHT. MODEL RH IN LATEST
BUFKIT RUNS DOES HINT AT FOG/LOW STRATUS FORMATION BETWEEN 06Z-14Z
TUESDAY...WITH BEST CHANCES OVER IN CENTRAL AND EASTERN ZONES.
LGT/VAR WIND CONDITIONS WILL ALSO AID IN FOG FORMATION IN THE
AFOREMENTIONED ZONES...SO WILL KEEP PREVIOUS MENTION OF FOG IN THE
FORECAST.
GOING INTO TUESDAY...SURFACE HIGH PRESSURE SETTLES OVER CENTRAL AND
EASTERN PLAINS. THIS IS GOING TO SET UP YET ANOTHER NICE DAY FOR
MUCH OF THE CWA. MUCH OF THE WESTERN CWA WILL SEE WAA AGAIN ON
SOUTHERLY FLOW...WHILE EASTERN ZONES WILL BE CLOSE ENOUGH TO SURFACE
RIDGE THAT WINDS WILL NOT BE MAJOR FACTOR...SO HAVE TAPERED HIGHS
FOR TOMORROW FROM WEST TO EAST...MID 50S WEST DOWN TO THE MID 40S
ACROSS EASTERN PORTIONS.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 310 AM MST TUE DEC 9 2014
APOLOGIZE FOR THE DELAYED ISSUANCE OF THIS DISCUSSION.
ANOTHER DAY...ANOTHER HUGE SWING IN THE FORECAST GUIDANCE...MAINLY
WITH REGARDS TO THE STRONG WEATHER SYSTEM THIS WEEKEND/EARLY NEXT
WEEK. MAIN DISCUSSION FOCUS IS ON A POTENTIAL SIGNIFICANT HIGH
PLAINS WINTER STORM. ONLY THING OF NOTE FOR FRIDAY THROUGH SATURDAY
IS THAT GUIDANCE WARMED TEMPS AGAIN FRIDAY...ESPECIALLY OVER THE
WESTERN FORECAST AREA. MADE A SMALL ADJUSTMENT TO INCREASE HIGHS.
TIME FOR THE MORE IMPORTANT DETAILS. FIRST...THE METEOROLOGY ASPECT
OF THIS SCENARIO. LATEST FORECAST GUIDANCE ON ALL ACCOUNTS HAS SHOWN
A MAJOR SHIFT IN THIS STORM SYSTEMS EVOLUTION. PREVIOUSLY...ALL...
AND I MEAN LITERALLY ALL...FORECAST GUIDANCE INDICATED A LARGE UPPER
LEVEL TROUGH DIGGING INTO THE SOUTHWESTERN UNITED STATES SATURDAY...
EJECTING OVER TEXAS SUNDAY AND SLOWLY PROGRESSING ON AN EASTERLY
COURSE NEXT WEEK. FOR THE LATEST 00Z MODEL RUNS...THE SCENARIO
REMAINS THE SAME UNTIL SUNDAY...THE DAY OF MOST CONCERN. MODELS NOW
INDICATE THAT A VIGOROUS SHORTWAVE TROUGH LEADS TO INTENSE LEE-SIDE
CYCLOGENESIS BY SUNDAY MORNING AND A STRONG...DEEPENING VERTICALLY
STACKED SYSTEM SLOWLY PROGRESSES NORTHEAST INTO THE HIGH PLAINS BY
SUNDAY NIGHT. THIS DEEP CYCLONE THEN HEADS SOMEWHERE EAST/NORTHEAST
AS MODEL GUIDANCE IS NOT IN GREAT AGREEMENT BEYOND MONDAY. LATEST
ENSEMBLE MEANS SUPPORT THE OPERATIONAL GFS...EUROPEAN AND CANADIAN
MODEL SCENARIOS OF A DEEP CYCLONE. HOWEVER...THERE REMAIN LARGE
DIFFERENCES IN TIMING/MOVEMENT. WHAT IS ASSURED IS THERE WILL BE A
VIGOROUS MID-LATITUDE CYCLONE MOVING ACROSS THE PLAINS SUNDAY/MONDAY.
THERE ARE SOME OTHER COMPLICATING FACTORS THAT COULD PLAY LARGE
ROLES THAT NEED TO BE RESOLVED. FIRST IS THE MOISTURE AVAILABILITY.
THERE ARE CONCERNS THAT WIDESPREAD THUNDERSTORM ACTIVITY OVER TEXAS
AND OKLAHOMA COULD CUT OFF MOISTURE ADVECTION TO THE HIGH PLAINS.
HOWEVER...THERE WILL BE 3-4 DAYS OF STRONG GULF MOISTURE ADVECTION
PRECEDING THIS SYSTEM. WHILE MOISTURE REINFORCEMENT MAY BE CUT OFF
BY SOUTHERN THUNDERSTORM ACTIVITY...FEEL THAT THERE WILL BE
SUFFICIENT MOISTURE. FORECAST GUIDANCE INDICATES THAT THE ICE
CRYSTAL GROWTH ZONE SATURATES AS THE MAIN PRECIPITATION PASSES
THROUGH WHICH FAVORS POTENTIAL SNOW. THE SECOND DRIVING FORCE IS
TIMING OF THE NEEDED COLD TEMPERATURES. A STRONG COLD FRONT SHOULD
BE THROUGH AT LEAST PARTS OF THE REGION BY SUNDAY MORNING PRECEDING
ANY PRECIPITATION DEVELOPMENT. THE COLD FRONT LOOKS TO BE COMPLETELY
THROUGH BY LATE SUNDAY MORNING. THEREFORE...THERE WOULD BE NO
TEMPERATURE CONCERNS BASED ON CURRENT GUIDANCE FOR THIS POTENTIAL
WINTER SYSTEM.
SO...WHAT DOES THIS ALL MEAN? WHILE CONFIDENCE IS NOT HIGH DUE TO
EXTREME RUN-TO-RUN GUIDANCE VARIABILITY...THERE IS AN INCREASED
POTENTIAL FOR A MAJOR WINTER STORM TO STRIKE THE REGION. HERE ARE
THE POSSIBILITIES AS THEY STAND NOW:
1. THE BEST CASE SCENARIO IS THAT THE SYSTEM REMAINS WELL TO THE
SOUTH AND RESULTS IN ONLY COOLER TEMPERATURES WITH GUSTY WINDS ON
SUNDAY. THIS WOULD MEAN THAT THIS LATEST SUITE OF GUIDANCE WAS
COMPLETELY OUT TO LUNCH AND THE PREVIOUS RUNS WERE RIGHT.
2. THE MORE LIKELY CASE...AND I SAY THAT WITH A GRAIN OF SALT...IS
THAT THIS SYSTEM PASSES JUST SOUTH OF THE FORECAST AREA. THIS
RESULTS IN PRECIPITATION DEVELOPING TO THE SOUTHWEST AND SPREADING
IN SUNDAY MORNING. COOLING TEMPS WOULD MEAN THAT THE MAIN PRECIP
TYPE IS SNOW BUT A PERIOD OF LIGHT RAIN/DRIZZLE IS POSSIBLE BEFORE
TEMPS DROP AND ICE CRYSTAL GROWTH ZONE SATURATES. THE WORST OF THE
WEATHER BYPASSES US TO THE SOUTH. GUSTY WINDS BEHIND THE FRONT MAY
LEAD TO SOME BLOWING SNOW.
3. THE WORST CASE SCENARIO IS BASICALLY WHAT ALL LATEST OPERATIONAL
MODEL RUNS HIGHLIGHT. A STRONG LOW PASSES JUST SOUTH OF THE REGION.
A LARGE SWATH OF PRECIPITATION DEVELOPS ON THE LOW`S NORTHWEST
SIDE...PASSING DIRECTLY OVER THE FORECAST AREA. DEPENDING ON THE
TIMING OF THE COLD FRONT...A BRIEF PERIOD OF RAIN MAY OCCUR SUNDAY
MORNING BEFORE PRECIPITATION CHANGES TO SNOW BY SUNDAY AFTERNOON. A
LARGE AMOUNT OF PRECIPITATION IS INDICATED AND WOULD LIKELY FALL IN
THE FORM OF SNOW. GUSTY NORTH WINDS PRODUCE BLOWING/DRIFTING SNOW.
IN THIS SCENARIO...A CRIPPLING WINTER STORM IS POSSIBLE. WHILE THIS
SCENARIO IS QUITE WORRISOME...IT IS TOUGH TO COMPLETELY SUPPORT THIS
SCENARIO AS WHAT WILL HAPPEN SINCE THIS IS THE FIRST RUN WHERE MOST
GUIDANCE SUGGESTS AN INTENSE WINTER STORM WILL HAPPEN.
AFTER ALL OF THIS...WHAT DO YOU NEED TO KNOW? AGAIN...A SIGNIFICANT
WINTER STORM IS POSSIBLE ON SUNDAY/MONDAY. HOWEVER...CONFIDENCE IS
QUITE LOW ON THE EVOLUTION AND IMPACTS OF THIS SYSTEM. FUTURE
FORECAST UPDATES MUST BE MONITORED FOR THE LATEST INFORMATION ON
THIS INCOMING SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1000 PM MST MON DEC 8 2014
KGLD...VFR THROUGH 12Z WITH WINDS UNDER 5KTS AND A FEW HIGH
CLOUDS. A FEW STRATUS CLOUDS MAY BE SEEN EAST OF THE TERMINAL
AROUND 12Z-13Z BECOMING BKN OVER THE TERMINAL WITH SOME BR AND
REDUCED VISIBILITIES IN THE 14Z-16Z TIME FRAME. IFR CONDITIONS ARE
EXPECTED. UNDER A SCATTERED TO BROKEN LAYER OF CIRRUS FROM 19Z
THROUGH 04Z WINDS GENERALLY FROM THE SOUTH TO SOUTHEAST AROUND
11KTS VEERING TO THE SOUTHWEST AROUND 7KTS FROM 05Z-06Z.
KMCK...VFR THROUGH 09Z WITH WINDS UNDER 5KTS AND A FEW HIGH
CLOUDS. FROM 09Z THROUGH 18Z VLIFR CIGS/VIS EXPECTED TO MOVE IN
FROM THE NORTHEAST WITH LIGHT/VARIABLE WINDS. AROUND 19Z THROUGH
THE REST OF THE TAF PERIOD STRATUS EXPECTED TO THIN OUT ENOUGH TO
PRODUCE VFR CONDITIONS WITH ONLY A LAYER OF CIRRUS AND
SOUTHEAST/EAST-SOUTHEAST WINDS AROUND 5KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR KSZ002>004-
014>016-028-029.
CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 10 AM MST /11 AM CST/ THIS MORNING FOR
NEZ079>081.
&&
$$
UPDATE...99
SHORT TERM...JN
LONG TERM...RRH
AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
403 AM CST TUE DEC 9 2014
...UPDATED LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 225 AM CST TUE DEC 9 2014
HIGH LEVEL CLOUD COVER WILL BE LIKELY TODAY ACROSS THE CENTRAL
HIGH PLAINS AS A COLD FRONT STALLS OUT IN EXTREME SOUTHWEST KANSAS
BY LATE MORNING. CONFIDENCE IS NOT HIGH ON HOW DENSE THESE CLOUDS
WILL BE BUT NAM, GFS, AND RAP ALL INDICATE A COOLING TREND IN THE
925MB TO 850MB LEVEL FROM 00Z TUESDAY TO 00Z WEDNESDAY. GIVEN THIS
COOLING TREND, MORE CLOUDS TODAY COMPARED TO YESTERDAY, AND AN
EASTERLY WIND WILL STAY CLOSE TO THE PREVIOUS FORECAST FOR HIGHS
THIS AFTERNOON. TEMPERATURES CLIMBING INTO THE UPPER 50S TO NEAR
60 STILL LOOKS REASONABLE IN EXTREME SOUTHWEST KANSAS WHICH WILL
BE NEAR/SOUTH OF THE COLD FRONT WHILE HIGHS ONLY IN THE MID 40S IN
NORTH CENTRAL KANSAS. EXACTLY HOW THE GRADIENT WILL END UP BETWEEN
THESE TWO EXTREMES IS UNCLEAR.
ISENTROPIC AND MOISTURE ADVECTION WILL IMPROVE ACROSS WESTERN
KANSAS IN THE 900MB TO 800MB LEVEL. STATUS ALONG WITH POSSIBLY
SOME AREAS OF FOG APPEARING LIKELY AS THE LOWER LEVELS SATURATE
OVERNIGHT. DEPTH OF THIS MOIST LAYER WILL BE IN THE 2000 TO 3000
FT AGL RANGE DEPENDING ON WHICH MODEL SOUNDING YOU EXAMINE. GIVEN
THE DEPTH OF THIS LAYER AM TRENDING AWAY FROM INTRODUCING DRIZZLE
LATE TONIGHT BUT IF THE NAM ENDS UP BEING MORE CORRECT THEN SOME
PATCHY DRIZZLE COULD DEVELOP TOWARDS DAYBREAK. TEMPERATURES ARE
EXPECTED TO FALL TO AROUND 32 DEGREES BUT GIVEN THE INCREASE IN
LOW LEVEL MOISTURE FORECAST OVERNIGHT THE LOWS MAY OCCUR EARLY
WITH TEMPERATURES THEN HOLDING NEARLY STEADY OR EVEN RISE A FEW
DEGREES AFTER MIDNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CST TUE DEC 9 2014
THE PERIOD BETWEEN WEDNESDAY AND SATURDAY WILL BE A TRUE CHALLENGE
WITH RESPECT TO SKY COVER AND RESULTING TEMPERATURES BOTH IN THE
DAYTIME FOR HIGHS AS WELL AS LOWS OVERNIGHT. RELATIVELY MORE MOIST
CONDITIONS IN THE BOUNDARY LAYER MARKED BY DEW POINTS IN THE UPPER
30S AND 40S COULD CONTRIBUTE TO EVENING/NIGHT FOG DEVELOPMENT IN
ADDITION TO ALREADY EXPECTED STRATUS. STRATUS THAT DOES ERODE
DURING THE DAY SHOULD BE ABLE RAPIDLY REDEVELOP ACROSS MUCH OF
CENTRAL KANSAS INTO THE EVENING AS THE BOUNDARY LAYER COOLS
DIURNALLY. MODELS SOUNDINGS GENERALLY LIMIT THE THICKNESS TO
SLIGHTLY MORE THAN 2000 FT, WHICH IS NOT FAVORABLE FOR DRIZZLE
DESPITE MODEL QPF OUTPUT. THE PRIMARY CHALLENGE WILL BE
DETERMINING HOW FAR WEST THE STRATUS IMPACTS THE FORECAST AREA
EACH DAY AND IT`S EFFECT ON TEMPERATURES. WEDNESDAY INTO THURSDAY
NIGHT APPEARS LIKELY TO BRING THE MOST WIDESPREAD OVERCAST
CONDITIONS, WHILE THE WESTERN MOST COUNTIES, GENERALLY WEST OF
HIGHWAY 83 WILL EXPERIENCE THE MOST HOURS OF INSOLATION AND CLEAR
SKIES DURING THIS TIMEFRAME.
UNLESS THE MODELS SIGNIFICANTLY DIVERGE IN SOLUTIONS FROM THE
CURRENT AND RECENT RUNS, SUNDAY NIGHT (OR AROUND THAT SYNOPTIC
TIMESCALE/TIMEFRAME) LOOKS WET WITH RAIN POTENTIAL OR EVEN SNOW
WITH AS UPPER DYNAMIC LOW PRESSURE MOVING THROUGH OR JUST SOUTH OF
THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1116 PM CST MON DEC 8 2014
A SECONDARY SURFACE COLD FRONT WILL MOVE INTO WESTERN KANSAS
OVERNIGHT. AS THIS FRONTAL BOUNDARY PASSES A NORTHEAST WIND AT
NEAR 10 KNOTS WILL DEVELOP. IN ADDITION TO THE NORTHEASTERLY
WINDS....AREAS OF STATUS AND FOG WILL BE POSSIBLE DURING THE
PREDAWN HOURS. BASED ON THE LATEST HRRR AND 900-840MB MOISTURE
PROFILES FROM THE RAP AND NAM IT CURRENTLY APPEARS THE AREA MORE
FAVORABLE FOR THE LOW MVFR/IFR LOW CLOUDS AND IFR VSBY IN FOG WILL
BE ALONG AND NORTH OF HIGHWAY 96 WHICH INCLUDES HAYS. THIS STATUS
AND FOG WILL GIVE WAY TO VFR CONDITIONS BY 15Z. FURTHER SOUTH VFR
CONDITIONS ARE EXPECTED OVERNIGHT AND TUESDAY. THE NORTHEAST WINDS
AT 10 KNOTS OR LESS WILL GRADUALLY VEER TO THE SOUTHEAST DURING
THE DAY AS A SURFACE RIDGE AXIS CROSSES CENTRAL AND EASTERN
KANSAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 49 33 47 37 / 0 10 10 0
GCK 52 31 50 33 / 0 10 10 0
EHA 59 34 57 33 / 0 0 0 0
LBL 56 36 56 35 / 0 10 10 0
HYS 42 29 43 35 / 0 10 10 0
P28 49 31 46 39 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
228 AM CST TUE DEC 9 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 225 AM CST TUE DEC 9 2014
HIGH LEVEL CLOUD COVER WILL BE LIKELY TODAY ACROSS THE CENTRAL
HIGH PLAINS AS A COLD FRONT STALLS OUT IN EXTREME SOUTHWEST KANSAS
BY LATE MORNING. CONFIDENCE IS NOT HIGH ON HOW DENSE THESE CLOUDS
WILL BE BUT NAM, GFS, AND RAP ALL INDICATE A COOLING TREND IN THE
925MB TO 850MB LEVEL FROM 00Z TUESDAY TO 00Z WEDNESDAY. GIVEN THIS
COOLING TREND, MORE CLOUDS TODAY COMPARED TO YESTERDAY, AND AN
EASTERLY WIND WILL STAY CLOSE TO THE PREVIOUS FORECAST FOR HIGHS
THIS AFTERNOON. TEMPERATURES CLIMBING INTO THE UPPER 50S TO NEAR
60 STILL LOOKS REASONABLE IN EXTREME SOUTHWEST KANSAS WHICH WILL
BE NEAR/SOUTH OF THE COLD FRONT WHILE HIGHS ONLY IN THE MID 40S IN
NORTH CENTRAL KANSAS. EXACTLY HOW THE GRADIENT WILL END UP BETWEEN
THESE TWO EXTREMES IS UNCLEAR.
ISENTROPIC AND MOISTURE ADVECTION WILL IMPROVE ACROSS WESTERN
KANSAS IN THE 900MB TO 800MB LEVEL. STATUS ALONG WITH POSSIBLY
SOME AREAS OF FOG APPEARING LIKELY AS THE LOWER LEVELS SATURATE
OVERNIGHT. DEPTH OF THIS MOIST LAYER WILL BE IN THE 2000 TO 3000
FT AGL RANGE DEPENDING ON WHICH MODEL SOUNDING YOU EXAMINE. GIVEN
THE DEPTH OF THIS LAYER AM TRENDING AWAY FROM INTRODUCING DRIZZLE
LATE TONIGHT BUT IF THE NAM ENDS UP BEING MORE CORRECT THEN SOME
PATCHY DRIZZLE COULD DEVELOP TOWARDS DAYBREAK. TEMPERATURES ARE
EXPECTED TO FALL TO AROUND 32 DEGREES BUT GIVEN THE INCREASE IN
LOW LEVEL MOISTURE FORECAST OVERNIGHT THE LOWS MAY OCCUR EARLY
WITH TEMPERATURES THEN HOLDING NEARLY STEADY OR EVEN RISE A FEW
DEGREES AFTER MIDNIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 152 PM CST MON DEC 8 2014
BY TUESDAY NIGHT, THE UPPER AIR FLOW OVER THE PLAINS WILL HAVE
TRANSITIONED TO A PSEUDO-NORTHWEST FLOW, WITH AN UPPER LEVEL RIDGE
BEGINNING TO BUILD IN AFTERWARDS. THAT UPPER LEVEL RIDGE WILL
EXIST FROM EASTERN NEW MEXICO THROUGH MINNESOTA, AND PERSIST
THROUGH ABOUT FRIDAY. THIS SHOULD MEAN VERY FEW CLOUDS DURING
THE DAY, WITH MAXIMUM TEMPERATURES IN THE 50S TO LOWER 60S.
MINIMUM TEMPERATURES WILL AVERAGE IN THE MID 30S TO MID 40S,
WARMING SLIGHTLY AS SATURDAY APPROACHES. NIGHTS WILL BE CLEAR WITH
LIGHT WINDS, AND SOME PATCHY FOG IS LIKELY MAINLY NORTH OF I-70
AND EAST OF HIGHWAY 183, TUESDAY NIGHT AND WEDNESDAY NIGHT. THERE
COULD BE SOME PATCHY FOG AS WELL THURSDAY NIGHT, BUT I HELD OFF ON
THAT FOR NOW.
SATURDAY WILL SEE AN UPPER LEVEL LOW PRESSURE TROUGH MOVE FROM THE
WESTERN ROCKIES TO NEAR THE EASTERN ROCKIES. THE LOW LEVEL FLOW
WILL TURN SOUTH, AS A COLD FRONT STARTS TO TRAVEL SOUTH THROUGH
THE PLAINS SATURDAY NIGHT. MOISTURE WILL ADVECT NORTH THROUGH THE
SOUTHERN PLAINS, AND A LITTLE CONVECTION MAY BE POSSIBLE IN OUR
FAR SOUTHEASTERN ZONES LATE SATURDAY NIGHT. SATURDAY WILL BE
FAIRLY WARM, WITH LOW TO MID 60S FOR HIGHS, WHICH WILL HELP
DESTABILIZE THE LOWER ATMOSPHERE BY LATE IN THE DAY. FOR NOW, I
PLACED RW IN THE GRIDS, AND WILL HAVE TO WAIT TO SEE LATER MODEL
RUNS TO DETERMINE IF THERE WILL BE ANY THUNDER GRIDS WILL BE NEEDED.
THAT COLD FRONT WILL PLUNGE THROUGH SATURDAY NIGHT, WITH THE UPPER
LOW PASSING TO OUR SOUTH THROUGH OKLAHOMA. RAINSHOWERS SEEM THE
BEST PRECIP CATEGORY FOR SUNDAY, WITH THE SUPERMODEL PLACING
NEARLY 50 PERCENT POPS IN THE BARBER COUNTY AREA, 25 TO 30 PERCENT
POPS IN THE HAYS TO DODGE CITY TO LIBERAL AREAS, AND LOWER 16 TO
20 PERCENT SLIGHT POPS FOR OUR WESTERN ZONES NEAR THE COLORADO
BOARDER. THE UPPER LOW PRESSURE MOVES EAST DURING THE NIGHT
SUNDAY NIGHT, AND THIS WILL HELP USHER SOME COLD AIR INTO OUR
FORECAST AREA. I HAVE WENT WITH A MIX OF RAIN OR SNOW FOR ALL OF
OUR FORECAST AREA SUNDAY NIGHT, EXCEPT IN THE FAR SOUTHEAST ZONES
FROM PRATT TO COMANCHE COUNTY, WHERE ONLY RAIN SHOWERS WERE
MENTIONED. SUNDAY WILL COOL OFF CONSIDERABLY, WITH HIGHS IN THE
MID 40S TO LOWER 50S. MINIMUM TEMPERATURES SUNDAY NIGHT WILL
RANGE FROM THE MID 20S FROM LACROSSE TO DODGE CITY TO LIBERAL AND
NORTHWESTWARD, AND TO THE UPPER 20S TO LOWER 30S SOUTHEAST OF
THAT LINE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1116 PM CST MON DEC 8 2014
A SECONDARY SURFACE COLD FRONT WILL MOVE INTO WESTERN KANSAS
OVERNIGHT. AS THIS FRONTAL BOUNDARY PASSES A NORTHEAST WIND AT
NEAR 10 KNOTS WILL DEVELOP. IN ADDITION TO THE NORTHEASTERLY
WINDS....AREAS OF STATUS AND FOG WILL BE POSSIBLE DURING THE
PREDAWN HOURS. BASED ON THE LATEST HRRR AND 900-840MB MOISTURE
PROFILES FROM THE RAP AND NAM IT CURRENTLY APPEARS THE AREA MORE
FAVORABLE FOR THE LOW MVFR/IFR LOW CLOUDS AND IFR VSBY IN FOG WILL
BE ALONG AND NORTH OF HIGHWAY 96 WHICH INCLUDES HAYS. THIS STATUS
AND FOG WILL GIVE WAY TO VFR CONDITIONS BY 15Z. FURTHER SOUTH VFR
CONDITIONS ARE EXPECTED OVERNIGHT AND TUESDAY. THE NORTHEAST WINDS
AT 10 KNOTS OR LESS WILL GRADUALLY VEER TO THE SOUTHEAST DURING
THE DAY AS A SURFACE RIDGE AXIS CROSSES CENTRAL AND EASTERN
KANSAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 49 33 56 37 / 0 10 10 0
GCK 52 31 57 33 / 0 10 10 0
EHA 59 34 59 33 / 0 0 0 0
LBL 56 36 60 35 / 0 10 10 0
HYS 42 29 50 35 / 0 10 10 0
P28 49 31 53 39 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1118 PM CST MON DEC 8 2014
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1116 PM CST MON DEC 8 2014
AT 00Z TUESDAY A 500MB TROUGH WAS LOCATED OVER CENTRAL MONTANA
WITH 40 METER 500MB 12 HOUR HEIGHT RISES REPORTED AT GLASGOW, MT,
130 METER HEIGHT RISES REPORTED AT BISMARK, ND AND 110 METER
HEIGHT RISES OBSERVED AT ABERDEEN, SD. FURTHER EAST A-27C 500MB
LOW WAS LOCATED ALONG THE WISCONSIN ILLINOIS BORDER. A +100 KNOT
250MB JET STREAK WAS JUST WEST SOUTHWEST OF THIS 500 MB LOW WITH
THE RIGHT EXIT REGION OF THIS JET BEING LOCATED OVER EASTERN
NEBRASKA. AT THE 700MB LEVEL A 700 MB BAROCLINIC ZONE WAS LOCATED
ACROSS THE CENTRAL PLAINS. 700MB TEMPERATURES VARIED FROM -4 AT
TOPEKA AND -6C AT OMAHA TO +2C AT DODGE CITY. A 850MB BAROCLINIC
ZONE EXTENDED FROM NORTHERN MISSOURI TO WESTERN SOUTH DAKOTA. AT
00Z TUESDAY ONE SURFACE BOUNDARY, WEAK COLD FRONT, EXTENDED FROM
NORTHERN ARKANSAS TO SOUTHWEST KANSAS TO NORTHEAST COLORADO.
ANOTHER COLD FRONT STRETCHED FROM SOUTHERN IOWA TO NORTHWEST
NEBRASKA. LOW CLOUDS WERE OBSERVED NORTH OF THE SECOND COLD FRONT
BASED ON SURFACE OBSERVATIONS AND 11-3.9 SATELLITE LOOP.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 208 PM CST MON DEC 8 2014
AN UPPER LEVEL SHORTWAVE TROUGH OVER THE NORTHERN PLAINS WILL PUSH
SOUTHEASTWARD ACROSS THE MISSISSIPPI VALLEY TONIGHT, FOLLOWED BY
ANOTHER WEAKER WAVE MOVING ACROSS THE NORTHERN PLAINS ON TUESDAY.
THE FIRST WAVE WILL PUSH A WEAK COLD FRONT ACROSS WESTERN KANSAS
AFTER MIDNIGHT TONIGHT WITH LIGHT AND VARIABLE WINDS SHIFTING TO
NORTHEAST AND NORTH AT 10 TO 15 MPH. SOME LOW STRATUS AND LIGHT FOG
WILL BE POSSIBLE MAINLY ACROSS THE I-70 CORRIDOR TOWARDS MORNING.
SOME HIGH LEVEL CLOUDINESS WILL STICK AROUND TONIGHT ACROSS THE REST
OF THE AREA. OVERNIGHT LOWS WILL BE RANGE FROM THE MID 20S ACROSS
THE I-70 CORRIDOR, TO THE UPPER 20S TO AROUND 30 ELSEWHERE ACROSS
WESTERN KANSAS.
ON TUESDAY, LIGHT EAST WINDS BECOME SOUTHEASTERLY UPSLOPE AT 10 TO
15 MPH. AS COOLER HIGH PRESSURE DRIFTS EAST, UNDER PARTLY CLOUDY
SKIES. HAVE LOWERED HIGHS A BIT WITH THE COOLER UPSLOPE FLOW AND
COOLER GUIDANCE TEMPS. WILL RANGE HIGHS FROM THE MID 40S ACROSS
I-70 TO THE LOW TO MID 50S ELSEWHERE. THE WARMEST LOOKS TO BE AT
ELKHART AROUND 60.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 152 PM CST MON DEC 8 2014
BY TUESDAY NIGHT, THE UPPER AIR FLOW OVER THE PLAINS WILL HAVE
TRANSITIONED TO A PSEUDO-NORTHWEST FLOW, WITH AN UPPER LEVEL RIDGE
BEGINNING TO BUILD IN AFTERWARDS. THAT UPPER LEVEL RIDGE WILL
EXIST FROM EASTERN NEW MEXICO THROUGH MINNESOTA, AND PERSIST
THROUGH ABOUT FRIDAY. THIS SHOULD MEAN VERY FEW CLOUDS DURING
THE DAY, WITH MAXIMUM TEMPERATURES IN THE 50S TO LOWER 60S.
MINIMUM TEMPERATURES WILL AVERAGE IN THE MID 30S TO MID 40S,
WARMING SLIGHTLY AS SATURDAY APPROACHES. NIGHTS WILL BE CLEAR WITH
LIGHT WINDS, AND SOME PATCHY FOG IS LIKELY MAINLY NORTH OF I-70
AND EAST OF HIGHWAY 183, TUESDAY NIGHT AND WEDNESDAY NIGHT. THERE
COULD BE SOME PATCHY FOG AS WELL THURSDAY NIGHT, BUT I HELD OFF ON
THAT FOR NOW.
SATURDAY WILL SEE AN UPPER LEVEL LOW PRESSURE TROUGH MOVE FROM THE
WESTERN ROCKIES TO NEAR THE EASTERN ROCKIES. THE LOW LEVEL FLOW
WILL TURN SOUTH, AS A COLD FRONT STARTS TO TRAVEL SOUTH THROUGH
THE PLAINS SATURDAY NIGHT. MOISTURE WILL ADVECT NORTH THROUGH THE
SOUTHERN PLAINS, AND A LITTLE CONVECTION MAY BE POSSIBLE IN OUR
FAR SOUTHEASTERN ZONES LATE SATURDAY NIGHT. SATURDAY WILL BE
FAIRLY WARM, WITH LOW TO MID 60S FOR HIGHS, WHICH WILL HELP
DESTABILIZE THE LOWER ATMOSPHERE BY LATE IN THE DAY. FOR NOW, I
PLACED RW IN THE GRIDS, AND WILL HAVE TO WAIT TO SEE LATER MODEL
RUNS TO DETERMINE IF THERE WILL BE ANY THUNDER GRIDS WILL BE NEEDED.
THAT COLD FRONT WILL PLUNGE THROUGH SATURDAY NIGHT, WITH THE UPPER
LOW PASSING TO OUR SOUTH THROUGH OKLAHOMA. RAINSHOWERS SEEM THE
BEST PRECIP CATEGORY FOR SUNDAY, WITH THE SUPERMODEL PLACING
NEARLY 50 PERCENT POPS IN THE BARBER COUNTY AREA, 25 TO 30 PERCENT
POPS IN THE HAYS TO DODGE CITY TO LIBERAL AREAS, AND LOWER 16 TO
20 PERCENT SLIGHT POPS FOR OUR WESTERN ZONES NEAR THE COLORADO
BOARDER. THE UPPER LOW PRESSURE MOVES EAST DURING THE NIGHT
SUNDAY NIGHT, AND THIS WILL HELP USHER SOME COLD AIR INTO OUR
FORECAST AREA. I HAVE WENT WITH A MIX OF RAIN OR SNOW FOR ALL OF
OUR FORECAST AREA SUNDAY NIGHT, EXCEPT IN THE FAR SOUTHEAST ZONES
FROM PRATT TO COMANCHE COUNTY, WHERE ONLY RAIN SHOWERS WERE
MENTIONED. SUNDAY WILL COOL OFF CONSIDERABLY, WITH HIGHS IN THE
MID 40S TO LOWER 50S. MINIMUM TEMPERATURES SUNDAY NIGHT WILL
RANGE FROM THE MID 20S FROM LACROSSE TO DODGE CITY TO LIBERAL AND
NORTHWESTWARD, AND TO THE UPPER 20S TO LOWER 30S SOUTHEAST OF
THAT LINE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1116 PM CST MON DEC 8 2014
A SECONDARY SURFACE COLD FRONT WILL MOVE INTO WESTERN KANSAS
OVERNIGHT. AS THIS FRONTAL BOUNDARY PASSES A NORTHEAST WIND AT
NEAR 10 KNOTS WILL DEVELOP. IN ADDITION TO THE NORTHEASTERLY
WINDS....AREAS OF STATUS AND FOG WILL BE POSSIBLE DURING THE
PREDAWN HOURS. BASED ON THE LATEST HRRR AND 900-840MB MOISTURE
PROFILES FROM THE RAP AND NAM IT CURRENTLY APPEARS THE AREA MORE
FAVORABLE FOR THE LOW MVFR/IFR LOW CLOUDS AND IFR VSBY IN FOG WILL
BE ALONG AND NORTH OF HIGHWAY 96 WHICH INCLUDES HAYS. THIS STATUS
AND FOG WILL GIVE WAY TO VFR CONDITIONS BY 15Z. FURTHER SOUTH VFR
CONDITIONS ARE EXPECTED OVERNIGHT AND TUESDAY. THE NORTHEAST WINDS
AT 10 KNOTS OR LESS WILL GRADUALLY VEER TO THE SOUTHEAST DURING
THE DAY AS A SURFACE RIDGE AXIS CROSSES CENTRAL AND EASTERN
KANSAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 28 51 39 56 / 0 0 10 10
GCK 27 52 36 57 / 0 0 10 10
EHA 30 58 33 59 / 0 0 10 0
LBL 29 56 39 60 / 0 0 10 10
HYS 22 44 33 50 / 0 0 10 10
P28 29 50 33 53 / 0 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...KRUSE
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1000 PM MST MON DEC 8 2014
.UPDATE...
ISSUED AT 925 PM MST MON DEC 8 2014
HAVE ISSUED A DENSE FOG ADVISORY FOR AREAS GENERALLY EAST OF A
LINE FROM TRENTON TO BREWSTER TO RUSSELL SPRINGS. 03Z RUC SIMILAR
TO LATEST HRRR OUTPUT AND 00Z NAM BOOSTING CONFIDENCE THAT DENSE
FOG WILL DEVELOP.
UPDATE ISSUED AT 745 PM MST MON DEC 8 2014
UPDATES REQUIRED FOR FIRST AND SECOND PERIODS (TONIGHT AND
TUESDAY) FOCUSING ON ARRIVAL OF POTENTIALLY DENSE FOG AND LOWER
TEMPERATURES THEN PREVIOUSLY FORECAST.
AT 0230Z CIRRUS SHIELD THAT WAS OVER THE AREA MOST OF THE DAY IS
MOVING EAST AND SLOWLY OUT OF THE AREA. AM EXPECTING MORE TO MOVE
IN LATER IN THE EVENING AND THROUGH THE DAY TOMORROW FROM THE
NORTHWEST.
AT THE SFC STRATUS PER SATELLITE OBS AND RUC 900MB RH FORECAST
CURRENTLY OVER NORTHEAST NEBRASKA/SOUTHWEST IOWA. BY 06Z THIS
NARROW CORRIDOR OF STRATUS FORECAST TO POSSIBLY REACH AREAS JUST
TO THE NORTHEAST FROM MCCOOK TO NORTON. AS SFC HIGH CONTINUES TO
BACK INTO THE AREA WITH LIGHT NORTHEAST WINDS STRATUS DECK
EXPECTED TO REACH A TRENTON TO HILL CITY LINE BY 09Z THEN ROUGHLY
A BENKELMAN TO COLBY AND OAKLEY LINE BY 12Z. IN THE TRENTON TO
HILL CITY AND POINTS NORTHEAST AREAS WINDS ARE CALM AND RH NEAR
100 PERCENT. LATEST RUC/HRRR/NAM VISIBILITY FORECASTS ALL SHOWING
DENSE FOG WITH VISIBILITIES 1/4 MILE OR LESS.
NAM EXTRAPOLATION OF SATURATED BOUNDARY LAYER RH PUSHES IT
FURTHER WEST TOWARD THE CO/KS BORDER WITH DENSE FOG CONTINUING
ROUGHLY FROM TRENTON TO HOXIE AND POINTS EAST. HRRR SUGGESTS
FURTHER WEST TOWARD BENKELMAN TO NEAR GOODLAND AND RUSSELL
SPRINGS.
WILL AWAIT THE 03Z RUC/LATEST HRRR BEFORE ZONE UPDATE SENT BUT
HAVE TRENDED TOWARD ABOVE THINKING.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 119 PM MST MON DEC 8 2014
DECENT AFTERNOON ACROSS THE ENTIRE FORECAST AREA...AS THE TRI STATE
REGION IS SEEING TEMPERATURES 15 TO 20 DEGREES ABOVE NORMAL WITH
READINGS WELL INTO THE 50S. THIS IS ONGOING DESPITE HIGH CLOUDS
MOVING OVER THE AREA CREATING SUNNY CONDITIONS.
HIGH CLOUD COVER WILL SCATTER OUT DURING THE EARLY EVENING HOURS IN
TIME FOR 925MB THERMAL BOUNDARY/SURFACE RIDGE AXIS COMBO...WHICH
MODELS BRING OVER THE REGION BY MIDNIGHT TONIGHT. MODEL RH IN LATEST
BUFKIT RUNS DOES HINT AT FOG/LOW STRATUS FORMATION BETWEEN 06Z-14Z
TUESDAY...WITH BEST CHANCES OVER IN CENTRAL AND EASTERN ZONES.
LGT/VAR WIND CONDITIONS WILL ALSO AID IN FOG FORMATION IN THE
AFOREMENTIONED ZONES...SO WILL KEEP PREVIOUS MENTION OF FOG IN THE
FORECAST.
GOING INTO TUESDAY...SURFACE HIGH PRESSURE SETTLES OVER CENTRAL AND
EASTERN PLAINS. THIS IS GOING TO SET UP YET ANOTHER NICE DAY FOR
MUCH OF THE CWA. MUCH OF THE WESTERN CWA WILL SEE WAA AGAIN ON
SOUTHERLY FLOW...WHILE EASTERN ZONES WILL BE CLOSE ENOUGH TO SURFACE
RIDGE THAT WINDS WILL NOT BE MAJOR FACTOR...SO HAVE TAPERED HIGHS
FOR TOMORROW FROM WEST TO EAST...MID 50S WEST DOWN TO THE MID 40S
ACROSS EASTERN PORTIONS.
.LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 135 PM MST MON DEC 8 2014
OLD FRONTAL BOUNDARY WILL RETURN EAST AS WARM FRONT AND STALL OUT
ACROSS THE FORECAST AREA TUESDAY NIGHT. EAST OF THE
FRONT...LOW LEVELS WILL SATURATE OVERNIGHT SETTING THE STAGE FOR
AREAS OF FOG AND DRIZZLE. SURFACE WET BULB TEMPERATURES WILL BE
IN THE LOWER 30S EAST OF THE BOUNDARY SO CANNOT TOTALLY RULE OUT
FREEZING DRIZZLE. NAM SOUNDINGS ARE CONSIDERABLY MORE MOIST OVER
A DEEPER LAYER COMPARED TO THE GFS SOUNDINGS...BUT EVEN IN THAT
SCENARIO ACCUMULATION WOULD ONLY BE A FEW HUNDREDTHS OF AN INCH.
NONETHELESS...WILL NEED TO MONITOR FOR POTENTIAL HIGHLIGHT FOR
FREEZING DRIZZLE. CLOUDS WILL SLOWLY ERODE WEST TO EAST WEDNESDAY
AFTERNOON...WITH EASTERN COUNTIES OF NORTHWEST KANSAS SUCH AS
NORTON AND GRAHAM POSSIBLY STUCK IN THE CLOUDS ALL DAY AND WILL
TREND MAX TEMPERATURES DOWN IN THOSE AREAS. CLOUDS WILL START TO
RETURN WEST WEDNESDAY NIGHT WITH AREAS OF FOG AND DRIZZLE
DEVELOPING ONCE AGAIN. THERE IS A NARROW BAND ON THE WESTERN EDGE
OF THE MOISTURE WHERE SURFACE WET BULBS DIP BELOW FREEZING AND
WILL CARRY A MENTION OF FREEZING DRIZZLE IN THOSE AREAS. CLOUDS
WILL ERODE WEST TO EAST A LITTLE MORE QUICKLY ON FRIDAY WITH
SUNNY SKIES BY THE AFTERNOON AND WARMER TEMPERATURES UNDER
SHORTWAVE RIDGING ALOFT.
A STRONG SYSTEM WILL MOVE OUT OF THE SOUTHERN ROCKIES LATE WEEK
AND EJECT ACROSS THE SOUTHERN PLAINS OVER THE WEEKEND. THIS TRACK
WILL BE TOO FAR SOUTH TO BRING PRECIPITATION CHANCES TO THE HIGH
PLAINS AND HAVE GONE WITH A DRY FORECAST. HOWEVER ASSOCIATED
SURFACE COLD FRONT WILL BRING COLDER TEMPERATURES SUNDAY AND
MONDAY WITH HIGHS IN THE 40S AND LOWS IN THE TEENS AND 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1000 PM MST MON DEC 8 2014
KGLD...VFR THROUGH 12Z WITH WINDS UNDER 5KTS AND A FEW HIGH
CLOUDS. A FEW STRATUS CLOUDS MAY BE SEEN EAST OF THE TERMINAL
AROUND 12Z-13Z BECOMING BKN OVER THE TERMINAL WITH SOME BR AND
REDUCED VISIBILITIES IN THE 14Z-16Z TIME FRAME. IFR CONDITIONS ARE
EXPECTED. UNDER A SCATTERED TO BROKEN LAYER OF CIRRUS FROM 19Z
THROUGH 04Z WINDS GENERALLY FROM THE SOUTH TO SOUTHEAST AROUND
11KTS VEERING TO THE SOUTHWEST AROUND 7KTS FROM 05Z-06Z.
KMCK...VFR THROUGH 09Z WITH WINDS UNDER 5KTS AND A FEW HIGH
CLOUDS. FROM 09Z THROUGH 18Z VLIFR CIGS/VIS EXPECTED TO MOVE IN
FROM THE NORTHEAST WITH LIGHT/VARIABLE WINDS. AROUND 19Z THROUGH
THE REST OF THE TAF PERIOD STRATUS EXPECTED TO THIN OUT ENOUGH TO
PRODUCE VFR CONDITIONS WITH ONLY A LAYER OF CIRRUS AND
SOUTHEAST/EAST-SOUTHEAST WINDS AROUND 5KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY FROM 5 AM TO 11 AM CST TUESDAY FOR KSZ002>004-
014>016-028-029.
CO...NONE.
NE...DENSE FOG ADVISORY FROM 4 AM MST /5 AM CST/ TO 10 AM MST /11 AM
CST/ TUESDAY FOR NEZ079>081.
&&
$$
UPDATE...99
SHORT TERM...JN
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
925 PM MST MON DEC 8 2014
.UPDATE...
ISSUED AT 925 PM MST MON DEC 8 2014
HAVE ISSUED A DENSE FOG ADVISORY FOR AREAS GENERALLY EAST OF A
LINE FROM TRENTON TO BREWSTER TO RUSSELL SPRINGS. 03Z RUC SIMILAR
TO LATEST HRRR OUTPUT AND 00Z NAM BOOSTING CONFIDENCE THAT DENSE
FOG WILL DEVELOP.
UPDATE ISSUED AT 745 PM MST MON DEC 8 2014
UPDATES REQUIRED FOR FIRST AND SECOND PERIODS (TONIGHT AND
TUESDAY) FOCUSING ON ARRIVAL OF POTENTIALLY DENSE FOG AND LOWER
TEMPERATURES THEN PREVIOUSLY FORECAST.
AT 0230Z CIRRUS SHIELD THAT WAS OVER THE AREA MOST OF THE DAY IS
MOVING EAST AND SLOWLY OUT OF THE AREA. AM EXPECTING MORE TO MOVE
IN LATER IN THE EVENING AND THROUGH THE DAY TOMORROW FROM THE
NORTHWEST.
AT THE SFC STRATUS PER SATELLITE OBS AND RUC 900MB RH FORECAST
CURRENTLY OVER NORTHEAST NEBRASKA/SOUTHWEST IOWA. BY 06Z THIS
NARROW CORRIDOR OF STRATUS FORECAST TO POSSIBLY REACH AREAS JUST
TO THE NORTHEAST FROM MCCOOK TO NORTON. AS SFC HIGH CONTINUES TO
BACK INTO THE AREA WITH LIGHT NORTHEAST WINDS STRATUS DECK
EXPECTED TO REACH A TRENTON TO HILL CITY LINE BY 09Z THEN ROUGHLY
A BENKELMAN TO COLBY AND OAKLEY LINE BY 12Z. IN THE TRENTON TO
HILL CITY AND POINTS NORTHEAST AREAS WINDS ARE CALM AND RH NEAR
100 PERCENT. LATEST RUC/HRRR/NAM VISIBILITY FORECASTS ALL SHOWING
DENSE FOG WITH VISIBILITIES 1/4 MILE OR LESS.
NAM EXTRAPOLATION OF SATURATED BOUNDARY LAYER RH PUSHES IT
FURTHER WEST TOWARD THE CO/KS BORDER WITH DENSE FOG CONTINUING
ROUGHLY FROM TRENTON TO HOXIE AND POINTS EAST. HRRR SUGGESTS
FURTHER WEST TOWARD BENKELMAN TO NEAR GOODLAND AND RUSSELL
SPRINGS.
WILL AWAIT THE 03Z RUC/LATEST HRRR BEFORE ZONE UPDATE SENT BUT
HAVE TRENDED TOWARD ABOVE THINKING.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 119 PM MST MON DEC 8 2014
DECENT AFTERNOON ACROSS THE ENTIRE FORECAST AREA...AS THE TRI STATE
REGION IS SEEING TEMPERATURES 15 TO 20 DEGREES ABOVE NORMAL WITH
READINGS WELL INTO THE 50S. THIS IS ONGOING DESPITE HIGH CLOUDS
MOVING OVER THE AREA CREATING SUNNY CONDITIONS.
HIGH CLOUD COVER WILL SCATTER OUT DURING THE EARLY EVENING HOURS IN
TIME FOR 925MB THERMAL BOUNDARY/SURFACE RIDGE AXIS COMBO...WHICH
MODELS BRING OVER THE REGION BY MIDNIGHT TONIGHT. MODEL RH IN LATEST
BUFKIT RUNS DOES HINT AT FOG/LOW STRATUS FORMATION BETWEEN 06Z-14Z
TUESDAY...WITH BEST CHANCES OVER IN CENTRAL AND EASTERN ZONES.
LGT/VAR WIND CONDITIONS WILL ALSO AID IN FOG FORMATION IN THE
AFOREMENTIONED ZONES...SO WILL KEEP PREVIOUS MENTION OF FOG IN THE
FORECAST.
GOING INTO TUESDAY...SURFACE HIGH PRESSURE SETTLES OVER CENTRAL AND
EASTERN PLAINS. THIS IS GOING TO SET UP YET ANOTHER NICE DAY FOR
MUCH OF THE CWA. MUCH OF THE WESTERN CWA WILL SEE WAA AGAIN ON
SOUTHERLY FLOW...WHILE EASTERN ZONES WILL BE CLOSE ENOUGH TO SURFACE
RIDGE THAT WINDS WILL NOT BE MAJOR FACTOR...SO HAVE TAPERED HIGHS
FOR TOMORROW FROM WEST TO EAST...MID 50S WEST DOWN TO THE MID 40S
ACROSS EASTERN PORTIONS.
.LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 135 PM MST MON DEC 8 2014
OLD FRONTAL BOUNDARY WILL RETURN EAST AS WARM FRONT AND STALL OUT
ACROSS THE FORECAST AREA TUESDAY NIGHT. EAST OF THE
FRONT...LOW LEVELS WILL SATURATE OVERNIGHT SETTING THE STAGE FOR
AREAS OF FOG AND DRIZZLE. SURFACE WET BULB TEMPERATURES WILL BE
IN THE LOWER 30S EAST OF THE BOUNDARY SO CANNOT TOTALLY RULE OUT
FREEZING DRIZZLE. NAM SOUNDINGS ARE CONSIDERABLY MORE MOIST OVER
A DEEPER LAYER COMPARED TO THE GFS SOUNDINGS...BUT EVEN IN THAT
SCENARIO ACCUMULATION WOULD ONLY BE A FEW HUNDREDTHS OF AN INCH.
NONETHELESS...WILL NEED TO MONITOR FOR POTENTIAL HIGHLIGHT FOR
FREEZING DRIZZLE. CLOUDS WILL SLOWLY ERODE WEST TO EAST WEDNESDAY
AFTERNOON...WITH EASTERN COUNTIES OF NORTHWEST KANSAS SUCH AS
NORTON AND GRAHAM POSSIBLY STUCK IN THE CLOUDS ALL DAY AND WILL
TREND MAX TEMPERATURES DOWN IN THOSE AREAS. CLOUDS WILL START TO
RETURN WEST WEDNESDAY NIGHT WITH AREAS OF FOG AND DRIZZLE
DEVELOPING ONCE AGAIN. THERE IS A NARROW BAND ON THE WESTERN EDGE
OF THE MOISTURE WHERE SURFACE WET BULBS DIP BELOW FREEZING AND
WILL CARRY A MENTION OF FREEZING DRIZZLE IN THOSE AREAS. CLOUDS
WILL ERODE WEST TO EAST A LITTLE MORE QUICKLY ON FRIDAY WITH
SUNNY SKIES BY THE AFTERNOON AND WARMER TEMPERATURES UNDER
SHORTWAVE RIDGING ALOFT.
A STRONG SYSTEM WILL MOVE OUT OF THE SOUTHERN ROCKIES LATE WEEK
AND EJECT ACROSS THE SOUTHERN PLAINS OVER THE WEEKEND. THIS TRACK
WILL BE TOO FAR SOUTH TO BRING PRECIPITATION CHANCES TO THE HIGH
PLAINS AND HAVE GONE WITH A DRY FORECAST. HOWEVER ASSOCIATED
SURFACE COLD FRONT WILL BRING COLDER TEMPERATURES SUNDAY AND
MONDAY WITH HIGHS IN THE 40S AND LOWS IN THE TEENS AND 20S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 400 PM MST MON DEC 8 2014
KGLD...VFR THROUGH 10Z WITH WINDS 5KTS OR LESS UNDER A LAYER OF
CIRRUS. FROM 11Z-17Z STRATUS/BR MOVE IN FROM THE NORTHEAST
BRINGING A PERIOD OF POSSIBLY IFR CIGS AND SOME REDUCED
VISIBILITIES. FROM 18Z THROUGH THE REST OF THE TAF PERIOD WINDS
FROM THE SOUTH NEAR 11KTS WITH BKN LAYER OF CIRRUS.
KMCK...VFR THROUGH 07Z WITH WINDS 5KTS OR LESS UNDER A LAYER OF
CIRRUS. FROM 08Z THROUGH 18Z IFR/VLIFR CIGS/VIS EXPECTED TO MOVE
IN FROM THE NORTHEAST WITH LIGHT/VARIABLE WINDS. AROUND 19Z
STRATUS EXPECTED TO THIN OUT ENOUGH TO PRODUCE VFR CONDITIONS WITH
ONLY A LAYER OF CIRRUS AND SOUTHEAST/EAST-SOUTHEAST WINDS AROUND
5KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY FROM 5 AM TO 11 AM CST TUESDAY FOR KSZ002>004-
014>016-028-029.
CO...NONE.
NE...DENSE FOG ADVISORY FROM 4 AM MST /5 AM CST/ TO 10 AM MST /11 AM
CST/ TUESDAY FOR NEZ079>081.
&&
$$
UPDATE...99
SHORT TERM...JN
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
245 AM EST TUE DEC 9 2014
.UPDATE...
ISSUED AT 1058 PM EST MON DEC 8 2014
THE SPOTTY RADAR RETURNS AND ANY SPRINKLES ASSOCIATED WITH THEM HAVE
LIFTED NORTH AND EAST OF THE AREA. BETTER RETURNS ARE OCCURRING
UPSTREAM IN SOUTHERN INDIANA CLOSER TO THE APPROACHING COLD FRONT AND
MID-LEVEL SHORT WAVE TROUGH. HAVE REMOVED THE MENTION OF SPRINKLES
FROM THE FORECAST AT THIS POINT...AWAITING THE MORE SUBSTANTIAL
SHOWERS FROM THE NORTHWEST. SOME OF THE SHELTERED VALLEYS HAVE TAKEN
ADVANTAGE OF SOME CLOUD THINNING CURRENTLY MOVING ACROSS THE
AREA...WITH THE BREATHITT COUNTY MESONET REPORTING 33 DEGREES AT THIS
TIME. HAVE TRIED TO REFLECT SIMILAR SPOTS LIKELY DIPPING INTO THE
LOW TO MID 30S HOWEVER...AS THE THICKER BLANKET OF LOWER CLOUDS MOVES
IN FROM THE WEST...EXPECT THESE READINGS TO WARM UP. UPDATES HAVE
BEEN SENT.
UPDATE ISSUED AT 730 PM EST MON DEC 8 2014
THE SURFACE WARM FRONT ASSOCIATED WITH THE GREAT LAKES LOW PRESSURE
SYSTEM IS CURRENTLY MOVING THROUGH EASTERN KENTUCKY. MOST OF THE
RADAR RETURNS HAVE ONLY RESULTED IN SOME SPOTTY SPRINKLES THUS FAR
AND THE LATEST HRRR ONLY SUPPORTS THIS UNTIL THE COLD FRONT ARRIVES
LATER TONIGHT INTO EARLY TUESDAY MORNING. AS SUCH...HAVE DIALED BACK
THE POPS A BIT FOR THE FIRST HALF OF THE NIGHT AND WILL ONLY CONTINUE
TO MENTION A FEW SPRINKLES POSSIBLE. TEMPERATURES ARE CURRENTLY
RUNNING IN THE LOW TO MID 40S FOR MOST LOCATIONS...HOWEVER A FEW
SPOTS HAVE DIPPED INTO THE UPPER 30S. BLACK MOUNTAIN AND THE PIKE
COUNTY MESONET HAVE BEEN HOVERING IN THE LOW TO MID 30S. THE LATEST
MODEL GUIDANCE SUPPORTS TEMPERATURES AT THESE HIGHER ELEVATIONS TO
REMAIN STEADY IF NOT FALL A BIT...ESPECIALLY TOWARDS DAWN WHEN THE
PRECIP THREATENS. AS SUCH...WILL MENTION A CHANCE OF SNOW SHOWERS FOR
ELEVATIONS ABOVE 2500 FEET. HAVE ADJUSTED THE TEMPERATURE CURVE FOR
THESE LOCATIONS ALL THE WAY THROUGH THE DAY ON TUESDAY...AS READINGS
WILL CONTINUE TO SLIDE THROUGH THE DAY. UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 359 PM EST MON DEC 8 2014
A DEEPENING TROUGH IS CURRENTLY SWEEPING ACROSS THE EASTERN
CONUS...WITH A UPPER LEVEL SHORT WAVE EXPECTED TO MOVE SE ACROSS
EASTERN KY BETWEEN 12 AND 18Z TUESDAY. AT THE SURFACE...AN AREA OF
LOW PRESSURE IS CURRENTLY TRAVERSING LAKE SUPERIOR. A COLD FRONT AND
WARM FRONT ARE EXTENDING SOUTHWARD FROM THIS LOW...WITH THE WARM
FRONT HAVING JUST MOVED FROM SW TO NE ACROSS THE CWA...AND THE COLD
FRONT EXPECTED TO TRAVERSE KY BETWEEN 6Z AND 12Z TONIGHT /MAY LINGER
A BIT LONGER IN THE FAR SE/.
WINDS REMAIN GENERALLY SRLY AS OF THIS AFTERNOON IN EASTERN
KY...WITH TEMP READINGS IN THE MID 40S TO AROUND 50 AT PRESENT TIME.
/THE CAVEAT TO THAT IS THE HIGHEST TERRAIN WHICH IS CURRENTLY ONLY
IN THE MID AND UPPER 30S. MOISTURE AHEAD OF THE APPROACHING COLD
FRONT IS CONTINUING TO ADVECT INTO THE REGION. THICK HIGH CLOUDS
WILL CONTINUE TO LOWER THROUGHOUT THE EVENING AND OVERNIGHT AS
MOISTURE WORKS ITS WAY DOWN TO THE SURFACE. AN AREA OF RADAR RETURNS
IS CURRENTLY MOVING ACROSS CENTRAL KY AND TN...TREKKING EASTWARD
TOWARDS THE JKL CWA. WHILE RETURNS HAVE LESSENED OVER THE LAST FEW
HOURS...THE AMOUNT OF DRY AIR AT THE SURFACE THROUGHOUT THE
MORNING/EARLY AFTERNOON HAS KEPT ANY OF THE RAIN FROM REACHING THE
GROUND ACROSS KY. WENT AHEAD AND INCLUDED SOME SLIGHT CHANCES ACROSS
THE NORTHERN CWA BY 0Z AS THIS AREA MOVES INTO OUR REGION...JUST IN
CASE SOME LIGHT SHOWER IS ABLE TO BREAK THROUGH TO THE SURFACE. AS
LOW LEVEL MOISTURE FINALLY BEGINS TO TAKE HOLD OVERNIGHT...EXPECT
THE BEST CHANCES FOR RAIN TO BEGIN FILLING INTO EASTERN KY AFTER 6Z
OVERNIGHT. THERE WILL BE AN ABUNDANT AMOUNT OF DRY AIR ALOFT...WITH
ONLY A SHALLOW LAYER OF LOW/MID LEVEL MOISTURE TO WORK WITH DURING
THIS EVENT. AS SUCH...ONLY WARRANTED CHANCE POPS AT THIS TIME...WITH
SCATTERED SHOWERS EXPECTED OPPOSED TO A WIDESPREAD RAIN EVENT.
THERE IS SOME QUESTION ABOUT THE PRECIP TYPE DURING THIS EVENT.
UNFORTUNATELY IT IS NOT A CUT AND DRY SITUATION. A FEW DEGREES
DIFFERENCE IN THE FIRST 1000 FEET COULD MAKE THE DIFFERENCE IN SNOW
OR RAIN. AS OF NOW...MOISTURE IS CONFINED TO 8K FT AND BELOW...WITH
NEARLY ALL OF THAT MOISTURE BELOW -10C HAVING NO INFLUENCE BY THE
DENDRITIC GROWTH ZONE. THIS WOULD FAVOR LITTLE IN THE WAY OF
SNOWFLAKE FORMATION. HOWEVER...TEMPS ARE BELOW FREEZING IN MUCH OF
THE MOIST LAYER...EXCEPT RIGHT AT THE LOWEST 1000 FT. SO IF THERE IS
ANY ICE/SNOW PELLETS...IT IS POSSIBLE THAT THEY MAY MELT ON THE WAY
DOWN TO THE SURFACE. OR...AS TEMPS OVERNIGHT AND ON THE HIGHEST
TERRAIN TOMORROW DIP DOWN SLIGHTLY...IT IS POSSIBLE THAT SOME
SNOW/ICE PELLETS MAY MELT AND SOME MAY NOT...MAKING IT POSSIBLE FOR
A MIXTURE OF SNOW AND ICE. TRIED TO STAY MORE OPTIMISTIC FOR THE
NEXT 24 HOURS...WITH MAINLY RAIN CHANCES ACROSS THE REGION...EXCEPT
IN PLACES ABOVE 1300 FEET THAT WILL EXPERIENCE SURFACE TEMPERATURES
NEAR OR JUST ABOVE FREEZING.
BY TOMORROW NIGHT...WHILE ALL OF THE ABOVE HOLDS TRUE...COLDER NE
AIR BEHIND THE FRONTAL BOUNDARY WILL BEGIN PULLING INTO THE REGION.
THIS MAY BE ENOUGH TO DROP TEMPS CLOSER TO THAT FREEZING MARK AND
SLIGHTLY BELOW...ALLOWING MORE SNOW TO MIX IN WITH THE RAIN...OR IN
A FEW PLACES...FALL AS SNOW ONLY. STILL...GIVEN THE WET AND SLIGHTLY
WARMER SURFACE TEMPS...THE ONLY SNOW ACCUMULATIONS AT THIS POINT ARE
IN THE HIGHEST TERRAIN AROUND BLACK MOUNTAIN TUESDAY NIGHT/WEDNESDAY
MORNING. DRY AIR ALOFT WILL CONTINUE TO INCREASE THROUGHOUT THE
OVERNIGHT HOURS...ESPECIALLY JUST BEHIND THE INITIAL COLD FRONTAL
PASSAGE. THIS WILL WORK TO MAKE THE LAYER OF MOISTURE EVEN
SHALLOWER...WHILE A IMPRESSIVELY STRONG INVERSION TAKES HOLD IN THE
MID LEVELS. AS SUCH...IT IS STILL BORDERLINE AND SOMEWHAT UNCLEAR AS
TO IF THE PRECIP THAT FALLS TUESDAY NIGHT WILL BE LIGHT
RAIN/SNOW...OR MAYBE A WINTRY DRIZZLE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 AM EST TUE DEC 9 2014
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT FOR THE BULK OF THE
EXTENDED AS THEY SLOWLY DRIFT THE LARGE EASTERN LOW AWAY FROM
KENTUCKY INTO THE UPCOMING WEEKEND. THIS BLOCKING LOW WILL KEEP THE
WX QUIET OVER THE OHIO VALLEY FOR THE MAJORITY OF THE EXTENDED
PORTION OF THE FORECAST. HOWEVER...SOME LINGERING CYCLONIC FLOW OVER
THE CENTRAL APPALACHIANS AND A WAVE SLIPPING PAST KENTUCKY TO THE
SOUTH MAY HAVE A FLEETING EFFECT ON SENSIBLE WEATHER WEDNESDAY NIGHT
IN THE FAR EAST. OTHERWISE...THROUGH SUNDAY...HEIGHT RISES AND AN
ABSENCE OF MID LEVEL ENERGY IN THE WAKE OF THE EASTERN LOW WILL KEEP
THINGS QUIET ACROSS EASTERN KENTUCKY. BY SUNDAY...A RELATIVELY
STRONG RIDGE WILL BE LOCATED OVER THE AREA IN ALL THE MODELS WITH
THE ECMWF PREFERRED OWING TO ITS SLOWER EXIT OF THE EASTERN TROUGH
IN THIS BLOCKY PATTERN. THIS RIDGE WILL SWEEP EAST OF THE STATE
LATER MONDAY AHEAD OF A CLOSED SOUTHERN STREAM LOW MOVING THROUGH
THE SOUTHERN PLAINS...IN CONJUNCTION WITH A NORTHERN CENTER FOUND
JUST NORTH OF THE CANADIAN BORDER. THIS SOLUTION IS PREFERRED
COMPARED TO THE GFS/S AS IT DOES A BETTER JOB OF KEEPING ITS STREAMS
SEPARATE AND SLOWER.
SENSIBLE WEATHER MAY FEATURE SOME LINGERING LIGHT SNOW SHOWERS/
FLURRIES OVER THE HIGHEST TERRAIN IN THE FAR EASTERN PARTS OF
KENTUCKY. A GRADUALLY MODERATING BUBBLE OF HIGH PRESSURE THEN
SETTLES OVER THE AREA AND HOLDS QUIET AND SEASONABLY PLEASANT WX IN
PLACE THROUGH THE WEEKEND. THE ECMWF/S IDEA OF A SFC LOW COMING OUT
OF THE SOUTHERN PLAINS FOR LATER MONDAY SEEMS REASONABLE...BUT THIS
WOULD KEEP EASTERN KENTUCKY DRY UNTIL PERHAPS LATER MONDAY NIGHT
INTO NEXT TUESDAY IN CONTRAST TO THE GFS/S VERSION OF A WEAKENING
COLD FRONT PASSING THROUGH THE STATE BY 00Z TUESDAY. HAVE GONE
CLOSER TO THE ECMWF FOR THIS TIME FRAME.
THE CR GRID LOAD PROVIDED A DECENT START FOR THE EXTENDED FORECAST
WITH CHANGES MAINLY MADE TO BETTER REFLECT THE LATEST ECMWF SOLUTION
IN THE LATTER PART OF THE FORECAST VIA LOWER POPS ON MONDAY. ALSO
MADE SOME TYPICAL RIDGE AND VALLEY TEMPERATURE CHANGES FOR LOWS
EACH NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1233 AM EST TUE DEC 9 2014
VFR CONDITIONS WILL BE IN PLACE TO BEGIN THE TAF PERIOD...AND THEN A
PASSING COLD FRONT WILL ALLOW FOR MVFR TO IFR CEILINGS TO FILL IN
FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA BETWEEN 06 AND 12Z. LIGHT
PRECIPITATION WILL ALSO ACCOMPANY THE FRONT...WITH MOST OF THIS
PRECIPITATION OCCURRING BETWEEN 12 AND 18Z TUESDAY. CEILINGS MAY THEN
RAISE A BIT INTO THE AFTERNOON...WITH THE EXCEPTION OF THE FAR
SOUTHEAST...WHERE MORE SUSTAINED RAIN AND OR SNOW SHOWERS WILL
CONTINUE TO BE SEEN THROUGH TUESDAY EVENING. SOUTHEAST TO SOUTH WINDS
OF AROUND 5 KTS WILL VEER AROUND TO THE NORTHWEST AND INCREASE TO
AROUND 10 KTS BY EARLY THIS MORNING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JMW
LONG TERM...GREIF
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
1233 AM EST TUE DEC 9 2014
.UPDATE...
ISSUED AT 1058 PM EST MON DEC 8 2014
THE SPOTTY RADAR RETURNS AND ANY SPRINKLES ASSOCIATED WITH THEM HAVE
LIFTED NORTH AND EAST OF THE AREA. BETTER RETURNS ARE OCCURRING
UPSTREAM IN SOUTHERN INDIANA CLOSER TO THE APPROACHING COLD FRONT AND
MID-LEVEL SHORT WAVE TROUGH. HAVE REMOVED THE MENTION OF SPRINKLES
FROM THE FORECAST AT THIS POINT...AWAITING THE MORE SUBSTANTIAL
SHOWERS FROM THE NORTHWEST. SOME OF THE SHELTERED VALLEYS HAVE TAKEN
ADVANTAGE OF SOME CLOUD THINNING CURRENTLY MOVING ACROSS THE
AREA...WITH THE BREATHITT COUNTY MESONET REPORTING 33 DEGREES AT THIS
TIME. HAVE TRIED TO REFLECT SIMILAR SPOTS LIKELY DIPPING INTO THE
LOW TO MID 30S HOWEVER...AS THE THICKER BLANKET OF LOWER CLOUDS MOVES
IN FROM THE WEST...EXPECT THESE READINGS TO WARM UP. UPDATES HAVE
BEEN SENT.
UPDATE ISSUED AT 730 PM EST MON DEC 8 2014
THE SURFACE WARM FRONT ASSOCIATED WITH THE GREAT LAKES LOW PRESSURE
SYSTEM IS CURRENTLY MOVING THROUGH EASTERN KENTUCKY. MOST OF THE
RADAR RETURNS HAVE ONLY RESULTED IN SOME SPOTTY SPRINKLES THUS FAR
AND THE LATEST HRRR ONLY SUPPORTS THIS UNTIL THE COLD FRONT ARRIVES
LATER TONIGHT INTO EARLY TUESDAY MORNING. AS SUCH...HAVE DIALED BACK
THE POPS A BIT FOR THE FIRST HALF OF THE NIGHT AND WILL ONLY CONTINUE
TO MENTION A FEW SPRINKLES POSSIBLE. TEMPERATURES ARE CURRENTLY
RUNNING IN THE LOW TO MID 40S FOR MOST LOCATIONS...HOWEVER A FEW
SPOTS HAVE DIPPED INTO THE UPPER 30S. BLACK MOUNTAIN AND THE PIKE
COUNTY MESONET HAVE BEEN HOVERING IN THE LOW TO MID 30S. THE LATEST
MODEL GUIDANCE SUPPORTS TEMPERATURES AT THESE HIGHER ELEVATIONS TO
REMAIN STEADY IF NOT FALL A BIT...ESPECIALLY TOWARDS DAWN WHEN THE
PRECIP THREATENS. AS SUCH...WILL MENTION A CHANCE OF SNOW SHOWERS FOR
ELEVATIONS ABOVE 2500 FEET. HAVE ADJUSTED THE TEMPERATURE CURVE FOR
THESE LOCATIONS ALL THE WAY THROUGH THE DAY ON TUESDAY...AS READINGS
WILL CONTINUE TO SLIDE THROUGH THE DAY. UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 359 PM EST MON DEC 8 2014
A DEEPENING TROUGH IS CURRENTLY SWEEPING ACROSS THE EASTERN
CONUS...WITH A UPPER LEVEL SHORT WAVE EXPECTED TO MOVE SE ACROSS
EASTERN KY BETWEEN 12 AND 18Z TUESDAY. AT THE SURFACE...AN AREA OF
LOW PRESSURE IS CURRENTLY TRAVERSING LAKE SUPERIOR. A COLD FRONT AND
WARM FRONT ARE EXTENDING SOUTHWARD FROM THIS LOW...WITH THE WARM
FRONT HAVING JUST MOVED FROM SW TO NE ACROSS THE CWA...AND THE COLD
FRONT EXPECTED TO TRAVERSE KY BETWEEN 6Z AND 12Z TONIGHT /MAY LINGER
A BIT LONGER IN THE FAR SE/.
WINDS REMAIN GENERALLY SRLY AS OF THIS AFTERNOON IN EASTERN
KY...WITH TEMP READINGS IN THE MID 40S TO AROUND 50 AT PRESENT TIME.
/THE CAVEAT TO THAT IS THE HIGHEST TERRAIN WHICH IS CURRENTLY ONLY
IN THE MID AND UPPER 30S. MOISTURE AHEAD OF THE APPROACHING COLD
FRONT IS CONTINUING TO ADVECT INTO THE REGION. THICK HIGH CLOUDS
WILL CONTINUE TO LOWER THROUGHOUT THE EVENING AND OVERNIGHT AS
MOISTURE WORKS ITS WAY DOWN TO THE SURFACE. AN AREA OF RADAR RETURNS
IS CURRENTLY MOVING ACROSS CENTRAL KY AND TN...TREKKING EASTWARD
TOWARDS THE JKL CWA. WHILE RETURNS HAVE LESSENED OVER THE LAST FEW
HOURS...THE AMOUNT OF DRY AIR AT THE SURFACE THROUGHOUT THE
MORNING/EARLY AFTERNOON HAS KEPT ANY OF THE RAIN FROM REACHING THE
GROUND ACROSS KY. WENT AHEAD AND INCLUDED SOME SLIGHT CHANCES ACROSS
THE NORTHERN CWA BY 0Z AS THIS AREA MOVES INTO OUR REGION...JUST IN
CASE SOME LIGHT SHOWER IS ABLE TO BREAK THROUGH TO THE SURFACE. AS
LOW LEVEL MOISTURE FINALLY BEGINS TO TAKE HOLD OVERNIGHT...EXPECT
THE BEST CHANCES FOR RAIN TO BEGIN FILLING INTO EASTERN KY AFTER 6Z
OVERNIGHT. THERE WILL BE AN ABUNDANT AMOUNT OF DRY AIR ALOFT...WITH
ONLY A SHALLOW LAYER OF LOW/MID LEVEL MOISTURE TO WORK WITH DURING
THIS EVENT. AS SUCH...ONLY WARRANTED CHANCE POPS AT THIS TIME...WITH
SCATTERED SHOWERS EXPECTED OPPOSED TO A WIDESPREAD RAIN EVENT.
THERE IS SOME QUESTION ABOUT THE PRECIP TYPE DURING THIS EVENT.
UNFORTUNATELY IT IS NOT A CUT AND DRY SITUATION. A FEW DEGREES
DIFFERENCE IN THE FIRST 1000 FEET COULD MAKE THE DIFFERENCE IN SNOW
OR RAIN. AS OF NOW...MOISTURE IS CONFINED TO 8K FT AND BELOW...WITH
NEARLY ALL OF THAT MOISTURE BELOW -10C HAVING NO INFLUENCE BY THE
DENDRITIC GROWTH ZONE. THIS WOULD FAVOR LITTLE IN THE WAY OF
SNOWFLAKE FORMATION. HOWEVER...TEMPS ARE BELOW FREEZING IN MUCH OF
THE MOIST LAYER...EXCEPT RIGHT AT THE LOWEST 1000 FT. SO IF THERE IS
ANY ICE/SNOW PELLETS...IT IS POSSIBLE THAT THEY MAY MELT ON THE WAY
DOWN TO THE SURFACE. OR...AS TEMPS OVERNIGHT AND ON THE HIGHEST
TERRAIN TOMORROW DIP DOWN SLIGHTLY...IT IS POSSIBLE THAT SOME
SNOW/ICE PELLETS MAY MELT AND SOME MAY NOT...MAKING IT POSSIBLE FOR
A MIXTURE OF SNOW AND ICE. TRIED TO STAY MORE OPTIMISTIC FOR THE
NEXT 24 HOURS...WITH MAINLY RAIN CHANCES ACROSS THE REGION...EXCEPT
IN PLACES ABOVE 1300 FEET THAT WILL EXPERIENCE SURFACE TEMPERATURES
NEAR OR JUST ABOVE FREEZING.
BY TOMORROW NIGHT...WHILE ALL OF THE ABOVE HOLDS TRUE...COLDER NE
AIR BEHIND THE FRONTAL BOUNDARY WILL BEGIN PULLING INTO THE REGION.
THIS MAY BE ENOUGH TO DROP TEMPS CLOSER TO THAT FREEZING MARK AND
SLIGHTLY BELOW...ALLOWING MORE SNOW TO MIX IN WITH THE RAIN...OR IN
A FEW PLACES...FALL AS SNOW ONLY. STILL...GIVEN THE WET AND SLIGHTLY
WARMER SURFACE TEMPS...THE ONLY SNOW ACCUMULATIONS AT THIS POINT ARE
IN THE HIGHEST TERRAIN AROUND BLACK MOUNTAIN TUESDAY NIGHT/WEDNESDAY
MORNING. DRY AIR ALOFT WILL CONTINUE TO INCREASE THROUGHOUT THE
OVERNIGHT HOURS...ESPECIALLY JUST BEHIND THE INITIAL COLD FRONTAL
PASSAGE. THIS WILL WORK TO MAKE THE LAYER OF MOISTURE EVEN
SHALLOWER...WHILE A IMPRESSIVELY STRONG INVERSION TAKES HOLD IN THE
MID LEVELS. AS SUCH...IT IS STILL BORDERLINE AND SOMEWHAT UNCLEAR AS
TO IF THE PRECIP THAT FALLS TUESDAY NIGHT WILL BE LIGHT
RAIN/SNOW...OR MAYBE A WINTRY DRIZZLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 410 PM EST MON DEC 8 2014
AN UPPER LEVEL LOW WILL MEANDER OF THE MID ATLANTIC STATES INTO THE
START OF THE WEEKEND. A SHORTWAVE TROUGH ROTATING AROUND THIS UPPER
LOW WILL WORK ACROSS EASTERN KY ON WED. ONCE THIS SYSTEM
DEPARTS...GRADUALLY RISING HEIGHTS ARE ANTICIPATED FROM THU INTO SAT
ACROSS ACROSS THE LOWER OH VALLEY AND EASTERN KY AS AN UPPER LEVEL
RIDGE BUILDS INTO MUCH OF THE EASTERN CONUS. THIS RIDGE WILL
GRADUALLY DEPART LATE IN THE PERIOD...EARLY NEXT WEEK AND ALLOW AN
UPPER LEVEL TROUGH TO MOVE INTO THE EASTERN CONUS.
MODEL AGREEMENT INTO THE WEEKEND AND EARLY NEXT WEEK IS ABOVE AVERAGE
WITH THE GENERAL PATTERN. THIS PATTERN WILL FAVOR BELOW NORMAL
TEMPERATURES FROM WED INTO FRI AS HIGH PRESSURE BUILDS ACROSS THE
AREA. AS FOR THE START OF THE PERIOD...MODELS HOLD ONTO SOME SHALLOW
MOISTURE AND UPSLOPE FLOW...BUT LAPSE RATES ARE NOT ALL THAT
IMPRESSIVE AND THE INVERSION HEIGHT IS NOT MUCH ABOVE THE -10C LEVEL
AS WELL. MODELS ALSO HAVE SOME DIFFERENCES AND ICE MAY NOT BE
PRESENT IN THE CLOUDS AT TIMES...ALTHOUGH MOISTURE SHOULD BE DEEPER
FROM 12Z TO 18Z...AND POSSIBLY LONGER ON WED. THE GFS OVERALL SHOWS
A BETTER POTENTIAL FOR ICE WITH MORE SATURATION IN THE -8C TO -10C
LEVELS OR HIGHER. THE BULK OF WHAT SNOW THAT DOES FALL SHOULD NOT BE
DENDRITES...BUT THE HIGHER ELEVATIONS AT 2000 FEET AND ABOVE SHOULD
REMAIN AT OR BELOW FREEZING ON WED AND COULD RECEIVE SOME LIGHT
ACCUMULATIONS. AS WITH MOST NW FLOW EVENTS...THERE IS SOME QUESTION
AS TO WHEN THE MOISTURE AND CLOUDS WILL DEPART. AT THIS TIME...WE
HAVE OPTED TO CONTINUE ON THE PESSIMISTIC SIDE WITH THE CLOUDS AND
MOISTURE DEPARTURE AND HAVE CONTINUED TO HOLD ONTO SLIGHT CHANCE OF
SNOW SHOWERS OR FLURRIES INTO WED EVENING.
HOWEVER...AS THE SFC HIGH BEGINS TO SHIFT EAST OF THE AREA THIS
WEEKEND...THE AIR MASS WILL MODERATE AND ABOVE NORMAL TEMPERATURES
WILL ENSUE THROUGH THE END OF THE PERIOD. OTHER THAN THE START OF
THE PERIOD...IT SHOULD BE DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1233 AM EST TUE DEC 9 2014
VFR CONDITIONS WILL BE IN PLACE TO BEGIN THE TAF PERIOD...AND THEN A
PASSING COLD FRONT WILL ALLOW FOR MVFR TO IFR CEILINGS TO FILL IN
FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA BETWEEN 06 AND 12Z. LIGHT
PRECIPITATION WILL ALSO ACCOMPANY THE FRONT...WITH MOST OF THIS
PRECIPITATION OCCURRING BETWEEN 12 AND 18Z TUESDAY. CEILINGS MAY THEN
RAISE A BIT INTO THE AFTERNOON...WITH THE EXCEPTION OF THE FAR
SOUTHEAST...WHERE MORE SUSTAINED RAIN AND OR SNOW SHOWERS WILL
CONTINUE TO BE SEEN THROUGH TUESDAY EVENING. SOUTHEAST TO SOUTH WINDS
OF AROUND 5 KTS WILL VEER AROUND TO THE NORTHWEST AND INCREASE TO
AROUND 10 KTS BY EARLY THIS MORNING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JMW
LONG TERM...JP
AVIATION...AR
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
329 PM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE COAST OF DELMARVA WILL STALL OVER LONG ISLAND
TONIGHT THROUGH WEDNESDAY...BEFORE DRIFTING NORTH OVER NEW ENGLAND
THROUGH FRIDAY. THE LOW THEN PUSHES OUT TO SEA INTO NEXT WEEK. HIGH
PRESSURE WILL BUILD OVER THE MID-ATLANTIC FRIDAY THROUGH MONDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
A FEW DEVELOPMENTS THIS MORNING TO TAKE NOTE OF. PERSISTENT
NORTHERLY FLOW BEING USHERED IN ON THE WEST SIDE OF THE SFC LOW
JUST OFFSHORE IS KEEPING PLENTY OF COLDER AIR IN PLACE. INITIAL
THOUGHT HAD BEEN OF THE SFC TEMPS WARMING IN THE AREA TO AT LEAST
MID 30S. BUT WITH TEMPS TO THE NORTH STILL SHOWING LOWER 30S...AND
WITH MULTIPLE MESO REPORTS SHOWING AROUND FREEZING IN OUR AREA...THE
LATEST THINKING IS THAT UNTIL THE WIND SHIFT TO THE NW LATE
TODAY...WE SHALL SEE PERSISTING FREEZING SFC TEMPS. ADD IN THE ON
GOING PCPN AND FREEZING RAIN REMAINS A THREAT OVER CENTRAL
MD...AND BLUE RIDGE AREAS AND TO THE WEST. 12Z RAP SOUNDINGS ALSO
SHOWING PLENTY OF DRYING ALOFT...SO VERY WELL COULD END UP WITH
JUST LIGHT DRIZZLE/FREEZING DRIZZLE. THUS...HAVE REISSUED A
WINTER WEATHER ADVISORY FOR THESE AREAS TO ACCOUNT FOR ANY
ADDITIONAL ICE ACCUM...GENERALLY ONLY EXPECTING LIGHT
AMTS...COUPLE HUNDREDTHS OF AN INCH OR LESS...ON TOP OF THE
CURRENTLY REPORTED ICE TOTALS WE HAVE BEEN RECEIVING...WITH
ISOLATED SPOTS UP TO A COUPLE TENTHS OF AN INCH. THIS ADVISORY IS
IN EFFECT UNTIL 23Z.
THE QUESTION BECOMES THEN FOR TONIGHT THE CHC FOR PCPN AND THE
FORM OF PCPN. GENERAL THOUGHT IS WITH THE WIND SHIFT TO A MORE
DEFINED NW FLOW...SHOULD SEE A TRANSITION TO UPSLOPING LIGHT SNOW
SHOWERS AND THE FREEZING RAIN/DRIZZLE THREAT DIMINISHING. SO FOR
NOW HAVE NOT CONTINUED THE ADVISORY THROUGH THE NIGHT TO ACCOUNT
FOR THE PCPN CHANGEOVER.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
BLUSTERY CONDS WL CONT TNGT AND WED AS THE LOW TRACKS OVR LONG
ISLAND...AND THEN NEW ENGLAND BRINGING A PROLONGED PD OF UNSETTLED
WX TO THE NERN U.S. TYPICALLY STRONG LOWS THAT FAR TO OUR N ARE
NOT BIG PCPN PRODUCERS IN THE MID ATLC..BUT WL KEEP CHC POPS IN
THE FCST. A STREAMER ALONG THE BAY SOMETIMES OCCURS IN THIS
SITUATION. THE BIGGER STORY WL BE THE WINDY CONDS THAT WL CONT
BOTH TNGT AND WED COURTESY OF THE PRES GRAD BTWN THE NERN LOW AND
HIGH PRES OVR THE MS VLLY.
LOWS TNGT IN THE 30S. HIGHS WED IN THE 40S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
WE WILL STILL FEEL THE EFFECTS OF THE LOW OVER NEW ENGLAND THURSDAY
AND FRIDAY. HOWEVER...THE BUILDING RIDGE OVER THE CNTRL CONUS SHOULD
SHUNT WRAP AROUND MOISTURE/CLOUDS/PRECIP EAST OF THE AREA BY FRIDAY.
ALSO...THE PRESSURE GRADIENT SHOULD BE WEAKER FRIDAY.
THURSDAY...STRONG NWLY FLOW CONTINUES...EXPECT GUSTS IN THE 25 TO 30
MPH RANGE (HIGHER ON RIDGES)...5 TO 10 MPH LESS THAN WEDNESDAY.
DOWNSLOPING FLOW SO TEMPERATURES WILL MAX OUT IN THE UPR 30S TO LOW
40S. THE REACH OF THE UPPER LOW STILL GETS SOUTH OF THE
MASON-DIXON...SO SOME LIGHT SHOWERS/FLURRIES ARE POSSIBLE...
PARTICULARLY NORTH OF HWY 50/I-66. UPSLOPE SNOW CONTINUES...BUT THE
INVERSION BECOMES MORE SHALLOW...AN INCH OR LESS POSSIBLE.
FRIDAY...DRIER WITH LESS PRESSURE GRADIENT. MAX TEMPS LOW TO MID
40S...UPSLOPE SNOW PROBABLY CUTS OFF THURSDAY NIGHT. NW WINDS GUST
TO AROUND 20 MPH.
THE LONG TERM PERIOD SHOULD BE RATHER QUIET AS FAR AS PRECIPITATION
IS CONCERNED.. HIGH PRESSURE OVER LABRADOR WILL BLOCK THE COASTAL
LOW...CAUSING IT TO STALL NEAR NEW ENGLAND THROUGH THE END OF THE
WEEK BEFORE MOVING OUT TO SEA SUNDAY. THIS WILL KEEP US IN BREEZY
NORTH TO NORTHWESTERLY FLOW WITH A DECENT AMOUNT OF CLOUD COVER INTO
SATURDAY NIGHT...MEANING THAT FRIDAY AND SATURDAY WILL FEEL LIKE
BLUSTERY MID-ATLANTIC WINTER DAYS.
RIDGING ALOFT AND HIGH PRESSURE AT THE SURFACE BUILDING IN FROM THE
SOUTH OVER THE WEEKEND WILL CLEAR SKIES TO MOSTLY SUNNY SUNDAY AND
MONDAY AS WELL AS ALLOW WINDS TO WEAKEN AND TEMPS TO MODERATE.
MODELS DIVERGE ON AN AREA OF LOW PRESSURE AT THE VERY END OF THE
PERIOD...WITH THE GFS MIGRATING OUR HIGH SOUTHWARD...BRINGING A
MID-LATITUDE LOW TO OUR NORTH...AND A COLD FRONT THROUGH THE
MID-ATLANTIC. THE EURO FAVORS THE HIGH MIGRATING SOUTHWARD AND THE
FORMATION OF A SOUTHERN STREAM LOW. CONFIDENCE IS LOW IN EITHER
SOLUTION HAVING MUCH IMPACT BEFORE TUESDAY NIGHT ASIDE FROM AN
INCREASE IN CLOUD COVER.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
GENERALLY MVFR CONDITIONS ACROSS THE TERMINALS...WITH WESTERN
SITES EVEN AT VFR NOW. IMPROVEMENT LOOKS TO BE SLOW TODAY...WITH
ALL SITES BECOMING VFR BY THIS EVENING. LOW-MOD CONFIDENCE AT THE
MOMENT ON THE IMPROVEMENT TIME. ANY PCPN AT THE TERMINALS SHOULD
REMAIN LIGHT RAIN/DRIZZLE DURING THIS TIME UNTIL TONIGHT...WITH
PSBL LIGHT SNOW MIXING IN THIS EVENING.
N WINDS BECOME NW THIS AFTN...WITH OCNL GUSTS MIXING IN DURING THE
AFTN HOURS.
VFR CONDS XPCTD FOR THE EVE PUSH AND THEN OVR AND WED. GUSTY N
WINDS XPCTD TO CONT THRU WED.
A LARGE UPPER-LEVEL LOW WILL BE ROTATING JUST EAST OF THE AREA...OFF
THE MID-ATLC NEW ENGLAND COAST FOR MUCH OF THE WEEK. GUSTY WINDS
FROM TUE NIGHT INTO WED. A FEW GUSTS WILL REMAIN INTO THU BUT MAINLY
TAPERING OFF AFTER A WINDY WED.
STRONG NW WINDS AND VFR PREVAIL THURSDAY AND FRIDAY. GUSTS TO 30 KT
ON THURSDAY AND AROUND 20 KT ON FRIDAY.
&&
.MARINE...
WINDS REACHING SCA LVLS TODAY THRU WED. GALE GUSTS MAY OCCUR ON WED.
WHILE AN OFFSHORE UPPER LOW ROTATES JUST OFF THE MID-ATLC
COAST...THE SFC PRESSURE GRADIENT WILL INCREASE AND CAUSE ANOTHER
ROUND OF HIGH-END SCA WED NIGHT. SOME BREEZES STILL OCCURRING ON THU
AS THE UPPER LOW SLOWLY WEAKENS AND MOVES OFF THE COAST NIGHT.
STRONG NW WIND CONTINUE THURSDAY ACROSS THE WATERS. FOR NOW...EXPECT
30 KT GUSTS...WILL NEED TO WATCH FOR BRIEF GALES CONTINUING FROM
WEDNESDAY. SCA ANTICIPATED THURSDAY INTO FRIDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MDZ004.
VA...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR VAZ501-
505-507-508.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ530>543.
&&
$$
SYNOPSIS...BAJ/SEARS
NEAR TERM...SEARS
SHORT TERM...SEARS
LONG TERM...BAJ/CEB
AVIATION...BAJ/SEARS
MARINE...BAJ/SEARS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1124 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE COAST OF DELMARVA WILL PUSH NORTH
TODAY...REACHING LONG ISLAND THIS EVENING. THE LOW IS EXPECTED TO
REMAIN NEARLY STATIONARY OVER NEW ENGLAND WEDNESDAY AND THURSDAY.
HIGH PRESSURE WILL MOVE OVER THE MID ATLANTIC THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A FEW DEVELOPMENTS THIS MORNING TO TAKE NOTE OF. PERSISTENT
NORTHERLY FLOW BEING USHERED IN ON THE WEST SIDE OF THE SFC LOW
JUST OFFSHORE IS KEEPING PLENTY OF COLDER AIR IN PLACE. INITIAL
THOUGHT HAD BEEN OF THE SFC TEMPS WARMING IN THE AREA TO AT LEAST
MID 30S. BUT WITH TEMPS TO THE NORTH STILL SHOWING LOWER 30S...AND
WITH MULTIPLE MESO REPORTS SHOWING AROUND FREEZING IN OUR AREA...THE
LATEST THINKING IS THAT UNTIL THE WIND SHIFT TO THE NW LATE
TODAY...WE SHALL SEE PERSISTING FREEZING SFC TEMPS. ADD IN THE ON
GOING PCPN AND FREEZING RAIN REMAINS A THREAT OVER CENTRAL
MD...AND BLUE RIDGE AREAS AND TO THE WEST. 12Z RAP SOUNDINGS ALSO
SHOWING PLENTY OF DRYING ALOFT...SO VERY WELL COULD END UP WITH
JUST LIGHT DRIZZLE/FREEZING DRIZZLE. THUS...HAVE REISSUED A
WINTER WEATHER ADVISORY FOR THESE AREAS TO ACCOUNT FOR ANY
ADDITIONAL ICE ACCUM...GENERALLY ONLY EXPECTING LIGHT
AMTS...COUPLE HUNDREDTHS OF AN INCH OR LESS...ON TOP OF THE
CURRENTLY REPORTED ICE TOTALS WE HAVE BEEN RECEIVING...WITH
ISOLATED SPOTS UP TO A COUPLE TENTHS OF AN INCH. THIS ADVISORY IS
IN EFFECT UNTIL 23Z.
THE QUESTION BECOMES THEN FOR TONIGHT THE CHC FOR PCPN AND THE
FORM OF PCPN. GENERAL THOUGHT IS WITH THE WIND SHIFT TO A MORE
DEFINED NW FLOW...SHOULD SEE A TRANSITION TO UPSLOPING LIGHT SNOW
SHOWERS AND THE FREEZING RAIN/DRIZZLE THREAT DIMINISHING. SO FOR
NOW HAVE NOT CONTINUED THE ADVISORY THROUGH THE NIGHT TO ACCOUNT
FOR THE PCPN CHANGEOVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
BLUSTERY CONDS WL CONT TNGT AND WED AS THE LOW TRACKS OVR LONG
ISLAND...AND THEN NEW ENGLAND BRINGING A PROLONGED PD OF UNSETTLED
WX TO THE NERN U.S. TYPICALLY STRONG LOWS THAT FAR TO OUR N ARE
NOT BIG PCPN PRODUCERS IN THE MID ATLC..BUT WL KEEP CHC POPS IN
THE FCST. A STREAMER ALONG THE BAY SOMETIMES OCCURS IN THIS
SITUATION. THE BIGGER STORY WL BE THE WINDY CONDS THAT WL CONT
BOTH TNGT AND WED COURTESY OF THE PRES GRAD BTWN THE NERN LOW AND
HIGH PRES OVR THE MS VLLY.
LOWS TNGT IN THE 30S. HIGHS WED IN THE 40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
LIKE THE CONSUMMATE EXAMPLE OF THE ANGULAR MOMENTUM LOST W/ A
WEAKENING LOW PRESSURE SYSTEM...THE VERTICALLY STACKED COASTAL LOW
WILL EXPAND BUT LOSE MUCH OF ITS POTENCY LATE IN THE WORK WEEK.
AFTER THE REINFORCING VORT MAX THAT IS CURRENTLY STRENGTHENING THE
SYSTEM PHASES OUT LATER TODAY...THE SYSTEM WILL NOT HAVE MUCH ELSE
TO CONTINUE ITS INTENSE PRESENCE. THE LACK OF WAA/CAA WILL TAKE ITS
TOLL ON THE SYSTEM...RISING HEIGHTS IN THE UPPER LOW AND SCATTERING
OUT THE PRECIP AS IT HOVERS OVER NEW ENGLAND FROM LATE WED INTO THU.
THE OFFSHORE PRECIP WILL MOVE FURTHER AWAY FROM LAND...W/ THE
ONSHORE PRECIP WEAKLY FORCED AND LIMITED TO THE LEFTOVER CIRCULAR
OUTER BANDS - SURROUNDING THE LOW.
MUCH OF THE PRECIP WILL STAY NORTH OF THE MASON-DIXON LINE...OUTSIDE
OF A FEW BATCHES OF UPSLOPE SHOWERS AND SNOW SHOWERS DURING THE LATE
STAGES OF THE LOW`S INFLUENCE. SOME PROLONGED ACCUMULATING SNOWS FOR
THE HIGHER TERRAIN WILL NEED TO BE MONITORED FOR THE APLCN SPINE...
W/ MUCH OF THE REST OF THE MID ATLC DRYING OUT. THE PROXIMITY OF THE
LARGE AND WEAKENING UPPER LOW LATE IN THE WEEK WILL KEEP OUR WX
MODERATED - NOT MUCH OF A WARM-UP EXPECTED. AVG HIGHS ARE IN THE
U40S FOR OUR REGION FOR THIS TIME OF YEAR WE WILL HAVE TO WAIT FOR
THE COMING WEEKEND TO APPROACH THESE VALUES...W/ A SLOW/STEADY CLIMB
UNTIL THEN.
SINCE LAST NIGHT...THE EURO INTO THE END OF THE WEEK HAS ACTUALLY
MOVED TOWARD THE GFS SOLUTION...THEN THEY DIVERGE AGAIN INTO THE
WEEKEND. AS THE PARENT UPPER LOW SLOWLY WEAKENS AND LOSES ITS
EARLIER POTENCY...THE OUTER PRECIP BANDS WILL CONTINUE TO EXPAND AND
DISSIPATE AS THEY ROTATE AROUND NEW ENGLAND. PLENTY OF LIGHT PRECIP
WILL SWING ABOUT THE CENTER OF THE LOW...BUT LITTLE IF ANY WILL MAKE
IT SOUTH OF THE MASON-DIXON LINE. THE GFS TAKES THAT ENTIRE SYSTEM
ON A GOOD NE JOG INTO THE WEEKEND...WHILE THE EURO KEEPS THE FEATURE
OVER SRN NEW ENGLAND...W/ ANOTHER MINOR DEEPENING PERIOD TO TIME -
JUST OFF THE MID ATLC. KEEPING THE LATEST FORECAST UPDATE W/ A BLEND
OF THE LONG RANGE DEPICTIONS...MAINLY A SLOW WARM-UP AND DRY FOR THE
AREA INTO EARLY NEXT WEEK.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
GENERALLY MVFR CONDITIONS ACROSS THE TERMINALS...WITH WESTERN
SITES EVEN AT VFR NOW. IMPROVEMENT LOOKS TO BE SLOW TODAY...WITH
ALL SITES BECOMING VFR BY THIS EVENING. LOW-MOD CONFIDENCE AT THE
MOMENT ON THE IMPROVEMENT TIME. ANY PCPN AT THE TERMINALS SHOULD
REMAIN LIGHT RAIN/DRIZZLE DURING THIS TIME UNTIL TONIGHT...WITH
PSBL LIGHT SNOW MIXING IN THIS EVENING.
N WINDS BECOME NW THIS AFTN...WITH OCNL GUSTS MIXING IN DURING THE
AFTN HOURS.
VFR CONDS XPCTD FOR THE EVE PUSH AND THEN OVR AND WED. GUSTY N
WINDS XPCTD TO CONT THRU WED.
A LARGE UPPER-LEVEL LOW WILL BE ROTATING JUST EAST OF THE AREA...OFF
THE MID-ATLC NEW ENGLAND COAST FOR MUCH OF THE WEEK. GUSTY WINDS
FROM TUE NIGHT INTO WED. A FEW GUSTS WILL REMAIN INTO THU BUT MAINLY
TAPERING OFF AFTER A WINDY WED.
&&
.MARINE...
WINDS REACHING SCA LVLS TODAY THRU WED. GALE GUSTS MAY OCCUR ON WED.
WHILE AN OFFSHORE UPPER LOW ROTATES JUST OFF THE MID-ATLC
COAST...THE SFC PRESSURE GRADIENT WILL INCREASE AND CAUSE ANOTHER
ROUND OF HIGH-END SCA WED NIGHT. SOME BREEZES STILL OCCURRING ON THU
AS THE UPPER LOW SLOWLY WEAKENS AND MOVES OFF THE COAST NIGHT.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR
MDZ003>005-502-503-505.
VA...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR
VAZ025>031-040-501-505-507-508.
WV...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR
WVZ051>053.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ530>543.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
619 PM EST WED DEC 10 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 332 PM EST WED DEC 10 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG
STRETCHING FM THE DESERT SW NEWD TOWARD HUDSON BAY...SUPPORTING A
SFC RDG AXIS FM JAMES BAY SWWD INTO WI. LOCAL 12Z RAOBS UNDER THIS
RDG AXIS SHOW A SHARP INVRN BTWN ABOUT H925 AND H95...WITH HI RH BLO
THIS SHARP INVRN. SFC OBS/STLT IMAGERY INDICATE THE LO CLDS HAVE
FINALLY DISSIPATED OVER UPR MI CLOSER TO THE CORE OF DRIER LLVL AIR
IN ONTARIO. THE LO CLD IS MORE EXTENSIVE OVER MN AND THE SW HALF OF
WI...CLOSER TO SOMEWHAT HIER INVRN TO H9/DEEPER LLVL MSTR SHOWN ON
THE 12Z MPX RAOB. THERE ARE SOME HI CLDS STREAMING ACRS THE CWA IN
THE NNW FLOW E OF UPR RDG AXIS...BUT THE 12Z INL/YPL RAOBS ARE SO
DRY IN THE MID LVLS THESE CLDS ARE THIN...AND THERE IS NO PCPN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LO CLD TRENDS/IMPACT
ON TEMPS.
TNGT...AS THE SFC HI PRES CENTER NEAR JAMES BAY SHIFTS TO THE NE...
ANOTHER HI CENTER AT THE SW EDGE OF THE RDG AXIS OVER WI IS PROGGED
TO BECOME THE DOMINANT FEATURE ON THE LLVL WIND FIELD OVER THE UPR
LKS. THE RESULT WL BE A SHIFT IN LLVL WIND DIRECTION TO A MORE W-NW
FLOW. THIS CHANGE SHOULD ALLOW A RETURN OF THE MORE EXTENSIVE LO
CLDS NOW DOMINATING MN AND WRN LK SUP. THE LO CLDS WL SLOWEST IN
RETURNING TO THE E AND SCENTRAL CWA...SO EXPECT THE LOWEST MIN TEMPS
NEAR THE LO END OF GUIDANCE IN THIS AREA. SINCE THESE LO TEMPS ARE
FCST TO FALL THRU FAIRLY HI DEWPTS OBSVD THIS AFTN WITH LGT WINDS
UNDER THE HI PRES RDG...ADDED SOME FOG TO SOME PLACES IN THESE
AREAS. ALSO OPTED TO INCLUDE A MENTION OF SOME FLURRIES/FREEZING DZ
OVER THE KEWEENAW LATE WITH A MORE PRONOUNCED UPSLOPE W WIND
COMPONENT WITHIN SHALLOW MSTR WEDGE/ LOWEST TEMPS NEAR -7C AT LO
INVRN BASE INADEQUATE TO ENSURE ICE CRYSTAL FORMATION.
THU...WITH LLVL NW FLOW REMAINING IN PLACE UNDER PERSISTENT UPR
RDG/LARGE SCALE SUBSIDENCE...EXPECT THE MOST LO CLD COVER IN AREAS
OVER THE W AND E DOWNWIND OF LK SUP. LINGERING FOG/FREEZING DZ AND
FLURRIES EARLY IN THE DAY SHOULD DISSIPATE BY LATE MRNG. THE
SCENTRAL CWA INFLUENCED BY THE DOWNSLOPE NW FLOW WL SEE THE MOST
SUNSHINE. MIXING TO JUST H925 YIELDS HI TEMPS RISING INTO THE 30S IN
THESE AREAS THAT HAVE MORE SUN...BUT MAX TEMPS SHOULD BE LOWER WHERE
THERE ARE MORE CLDS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 402 PM EST WED DEC 10 2014
THE ANOMALOUS UPPER RIDGE WILL BE OVER THE UPPER MISSISSIPPI VALLEY
AT THE START OF THE LONG TERM PERIOD AND SLOWLY SHIFT EAST ACROSS
THE UPPER GREAT LAKES REGION THROUGH THE FIRST HALF OF THE WEEKEND.
IN FACT...00Z NAEFS ENSEMBLE MEAN 500MB HEIGHT VALUES EXCEED
ANYTHING SEEN DURING THIS TIME OF YEAR BETWEEN 1979-2009 ON THE
CFSR. THUS...THE AREA WILL BE EXPERIENCING ABOVE NORMAL TEMPERATURES
DURING THAT PERIOD. THE HIGH PRESSURE RIDGE THAT WILL BE OVER THE
AREA TO START THE PERIOD (FROM A HIGH CENTERED IN THE MID
MISSISSIPPI VALLEY) WILL BE SLOWLY SINKING SOUTHEAST THROUGH THE
SOUTHEASTERN STATES THROUGH SATURDAY LEADING TO THE RIDGE TO
LOOSEN ITS GRIP ON THE AREA. BEFORE THAT OCCURS...THAT WARMING
PERIOD WILL SEE HIGHS GRADUALLY RISING THROUGH THE 30S FOR THE REST
OF THE WEEK AND IN THE UPPER 30S AND LOWER 40S ON SATURDAY. THE ONE
ITEM OF CONCERN DURING THIS PERIOD WILL BE THE POTENTIAL FOR LOW
CLOUDS BENEATH THE SUBSIDENCE INVERSION. ALTHOUGH THE AREA BROKE
OUT OF THE LOW CLOUDS TODAY...THE MODELS ARE INDICATING THE LOW
CLOUDS OVER MINNESOTA TO REMAIN IN PLACE AND SLOWLY SHIFT BACK
TOWARDS THE AREA THURSDAY NIGHT INTO FRIDAY AS THE RIDGE AXIS
SHIFTS THROUGH. THERE IS STILL SOME MODEL VARIABILITY IN THE
SOLUTIONS WITH THIS...BUT LIKE THE IDEA SHOWN BY THE PREVIOUS SHIFT
WITH GENERALLY MOSTLY CLOUDY CONDITIONS MOVING OVER THE AREA ON
THURSDAY NIGHT AND THEN GRADUALLY DIMINISHING ON FRIDAY.
AS THE RIDGE BEGINS TO SHIFT EAST OF THE AREA ON
SATURDAY...SOUTHWESTERLY FLOW WILL BEGIN TO DEVELOP OVER THE AREA
AND PULL ABUNDANT LOW LEVEL MOISTURE OVER THE U.P. FOR SATURDAY
NIGHT AND CONTINUING UNTIL A SURFACE TROUGH SWEEPS THROUGH THE AREA
SUNDAY NIGHT INTO MONDAY MORNING. THAT WILL LEAD TO A GENERALLY
DREARY PERIOD WITH LOW CLOUDS AND OCCASIONAL DRIZZLE/FOG. WILL LEAN
ON THE BETTER PERFORMING RAW MODEL GUIDANCE (IN THESE LOW CLOUD
SITUATIONS) FOR OVERNIGHT LOWS THIS WEEKEND...WHICH SHOULD KEEP
TEMPERATURES AT OR ABOVE FREEZING FROM SATURDAY THROUGH SUNDAY
NIGHT. THUS...IF ANY DRIZZLE OCCURS IT SHOULD STAY IN LIQUID FORM
UNLESS IF FALLS ON ANY UNTREATED OR EXISTING COLD SURFACES.
THE ELONGATED SURFACE TROUGH (STRETCHING FROM A LOW IN THE CENTRAL
PLAINS TO ANOTHER LOW NEAR JAMES BAY) WILL SHIFT THROUGH THE AREA
LATE SUNDAY NIGHT INTO MONDAY MORNING. THIS WILL LEAD TO COLDER AIR
GRADUALLY SHIFTING INTO THE AREA MONDAY INTO MONDAY NIGHT. AS THE
COLDER AIR MOVES INTO THE AREA...WILL SHOW A WEST/EAST TRANSITION TO
MORE FROZEN PRECIPITATION MONDAY INTO MONDAY EVENING. DEPENDING
ON THE TIMING OF THE COLD AIR ARRIVAL...MAY BE SOME STRUGGLE FOR ICE
CRYSTALS INITIALLY UNTIL THE DEEPER MOISTURE AND COLDER AIR
ARRIVE...GENERALLY ON MONDAY NIGHT.
ONE INTERESTING ITEM FOR THE FIRST PART OF NEXT WEEK IS THE
INTERACTION OF THE SHORTWAVE TIED TO THE SURFACE LOW MOVING
OUT OF THE CENTRAL PLAINS AND ANOTHER DROPPING SOUTHEAST OUT OF
CENTRAL CANADA. THE MODELS VARY ON THE HANDLING OF THESE WAVES
TUESDAY INTO WEDNESDAY...BUT EITHER WAY IT APPEARS THAT THERE WILL
BE LINGERING UPPER LEVEL ENERGY AND SURFACE TROUGH OVER THE GREAT
LAKES REGION FOR TUESDAY AND DEPARTING WEDNESDAY (WHILE AN
AREA OF HIGH PRESSURE MOVES INTO THE UPPER MISSISSIPPI VALLEY).
THESE VARYING SOLUTIONS LEAD TO A WIDE VARIETY OF IDEAS ON WHEN THE
COLD AIR MOVES IN AND HOW COLD THE 850MB TEMPS WILL BE TUESDAY INTO
WEDNESDAY. LOOKING AT THE 850MB TEMP ENSEMBLE MEMBERS/MEAN...THERE
IS AN EXTREMELY LARGE SPREAD IN GEFS MEMBERS WITH THE MEAN
SIGNIFICANTLY WARMER THAN THE 12Z GFS. THE 00Z ECMWF ENSEMBLE MEAN
ALSO SHOWS A LITTLE WARMER IDEA FOR THAT PERIOD...BUT THEN THE 12Z
ECMWF TRENDED COLDER AND TOWARDS THE 12Z GFS. WITH MODELS USUALLY
STRUGGLING ON THE INTERACTION OF SHORTWAVES AT THAT TIME
RANGE...HAVE LOW CONFIDENCE IN THE FORECAST FOR EARLY NEXT WEEK AND
WILL FOLLOW A GENERAL CONSENSUS (ALTHOUGH SLIGHTLY WARMER LOW LEVEL
TEMPS) THAN SHOWN BY THE RAW MODELS. THEREFORE...WILL SHOW LOW END
CHANCE POPS TO SHOW THE POTENTIAL FOR LES. IF THE COLDER
TEMPERATURES PAN OUT AND WITH NORTHERLY FLOW IN PLACE...COULD SEE
PERIODS OF STRONGER LAKE EFFECT SNOW IN THOSE SNOW BELTS TUESDAY
INTO WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 618 PM EST WED DEC 10 2014
AS THE WINDS SHIFT TO THE W TNGT IN THE PRESENCE OF DIURNAL
COOLING...MORE EXTENSIVE LO CLDS OVER MN/ WRN LK SUP WL RETURN AND
BRING CONDITIONS BACK DOWN TO IFR/LIFR. THE LOWEST LIFR CONDITIONS
WITH SOME FZDZ/ FLURRIES WL IMPACT CMX LATE TNGT/THU MRNG...WHEN AND
WHERE THE W WIND WL PRESENT A SHARPER UPSLOPE WIND COMPONENT. WITH A
DOWNSLOPE WIND...SAW HAS THE BEST CHANCE TO AVOID THE LOWER
CONDITIONS FOR A LONGER TIME.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 332 PM EST WED DEC 10 2014
LIGHT WINDS UNDER A SURFACE HI PRES RIDGE WILL BECOME NW AND
INCREASE UP TO 20-25 KTS ON THU AND THU NIGHT AS A HI CENTER
STRENGTHENS IN THE MID MISSISSIPPI RIVER VALLEY. AS THIS HI SHIFTS
TO THE E THRU THE WEEKEND...THIS FLOW WILL BACK TO THE SW BUT REMAIN
RELATIVELY LIGHT WITH UNUSUALLY HI STABILITY OVER THE WATERS.
FOLLOWING THE PASSAGE OF A COLD FRONT ON MON...N WINDS WILL INCREASE
UP TO 25-30 KTS UNDER TIGHTENING PRES GRADIENT AHEAD OF HI PRES
MOVING INTO SCENTRAL CANADA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...07
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
404 PM EST TUE DEC 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 346 PM EST TUE DEC 9 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR TROF
STRETCING S FM HUDSON BAY INTO THE SE CONUS DOWNSTREAM OF AN UPR RDG
IN THE PLAINS. SFC HI PRES UNDER THE THE UPR RDG STRETCHES FM NW
ONTARIO INTO MN. 12HR 00Z-12Z H5 HGT RISES IN THE 100-150M RANGE FM
YPL TO INL AND MPX INDICATE THE UPR RDG/SFC HI ARE BUILDING INTO THE
WRN GREAT LKS...BUT PLENTY OF LO CLDS/A FEW FLURRIES LINGER OVER THE
CWA EARLY THIS AFTN WITH LLVL MSTR TRAPPED IN NEAR SFC NNE FLOW OFF
LK SUP UNDER INVRN BASE THAT HAD LOWERED TO NEAR H95 BY 12Z AT INL
UNDER THE STRONG DNVA/SUBSIDENCE ASSOCIATED WITH THE INCOMING UPR
RDG. THE AIR TO THE N OF LK SUP IS QUITE A BIT DRIER PER THE 12Z YPL
RAOB...WITH SFC DEWPTS NEAR OR BLO 0F AT MOST PLACES IN ONTARIO.
SKIES ARE MOCLR THERE...AND ASSOCIATED DRYING IS TENDING TO BREAK UP
THE LO CLDS OVER THE NRN AND ERN PORTION OF LK SUP. BUT THIS CLRG IS
HAVING A HARD TIME MAKING MUCH PROGRESS TOWARD UPR MI.
MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON LO CLD TRENDS
AND IMPACT ON TEMPS.
TNGT...AS UPR RDG CONTINUES TO SHIFT SLOWLY TO THE E...SFC HI PRES
RDG IS FCST TO DRIFT SLOWLY E AS WELL...REACHING A LINE FM NEAR
JAMES BAY INTO NW WI BY 12Z WED. LOWERING INVRN BASE UNDER THE
ASSOCIATED SUBSIDENCE SHOULD END ANY LINGERING FLURRIES...BUT MODELS
HAVE TRENDED TO BE MORE PESSIMISTIC IN REGARDS TO CLEARING THE LO
CLDS...WHICH SEEMS CONSISTENT WITH RATHER SLOW OBSVD CLRG TREND.
BEST CHC FOR SOME CLRG WL BE OVER THE ERN CWA AS THE SLOWLY VEERING
LLVL FLOW TOWARD THE E WL DOWNSLOPE OFF ONTARIO AND LIMIT THE OVER
WATER TRAJECTORY. ONE OTHER AREA WHERE THERE MAY BE SOME CLRG IS
OVER THE FAR W...WHERE FLOW SHIFTING TOWARD THE SSE WL DOWNSLOPE AS
WELL. BUT THE SFC-H925 WINDS ARE FCST TO BE ONLY 5-10 KTS...SO THE
ASSOCIATED SUBSIDENCE MIGHT NOT BE SUFFICIENT TO BREAK UP THE LO
CLDS SIGNIFICANTLY. WL TEND TOWARD THE LOWEST MIN TEMPS OVER THE
INTERIOR E...WITH LINGERING CLDS HOLDING UP THE TEMPS ELSEWHERE.
WED...SFC HI PRES RDG AXIS IS PROGGED TO DRIFT ONLY SLOWLY E THRU
THE DAY...REMAINING OVER CENTRAL UPR MI THRU THE DAY. WITH CONTINUED
SUBSIDENCE...EXPECT LINGERING LO CLDS TO SLOWLY BREAK UP. THESE CLDS
SHOULD BE MOST PERSISTENT OVER THE HIER TERRAIN OF THE CENTRAL
CWA...BUT EVEN HERE THE CLDS SHOULD BREAK UP AS THE SUBSIDENCE INVRN
SINKS TO THE NEAR THE SFC AS SHOWN ON FCST SDNGS. TENDED TOWARD THE
LO END OF GUIDANCE FOR MAX TEMPS GIVEN HI STABILITY SHOWN ON FCST
SDNGS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 402 PM EST TUE DEC 9 2014
WEDNESDAY NIGHT THROUGH SATURDAY...A SURFACE RIDGE AND DRY AIR WILL
LINGER ACROSS MUCH OF THE MIDWEST AND UPPER GREAT LAKES REGION
THROUGH SATURDAY BEFORE SHIFTING SLOWLY TO THE SOUTHEAST. AT THE
SAME TIME...STRONG UPPER LEVEL 500MB RIDGING OVER THE PLAINS STATES
WEDNESDAY NIGHT WILL SHIFT SLOWLY EASTWARD WITH THE UPPER LEVEL
RIDGE AXIS BECOMING DIRECTLY OVERHEAD LATE FRIDAY NIGHT THROUGH MUCH
OF THE DAY SATURDAY. THIS WILL TRANSLATE TO MAINLY CLEAR...DRY AND
VERY QUIET WEATHER THROUGH THIS TIME PERIOD. TEMPERATURES WILL WARM
TO WELL ABOVE NORMAL FRIDAY INTO SATURDAY WITH HIGHS APPROACHING OR
EXCEEDING 40 DEGREES AS 850MB TEMPERATURES WARM TO AROUND 10 TO 12C.
SATURDAY NIGHT THROUGH TUESDAY...AS THE UPPER LEVEL RIDGE AXIS
SHIFTS TO THE EAST OF THE AREA SATURDAY NIGHT INTO SUNDAY...EXPECT
HEIGHTS TO SLOWLY FALL ACROSS THE AREA. AT THE SAME TIME...A WEAK
SURFACE TROUGH IS EXPECTED TO SLIDE ACROSS THE AREA. OVERALL
MOISTURE DOES NOT APPEAR TO OVERLY ABUNDANT OR DEEP...AS A LOW IS
EXPECTED TO DEVELOP OVER THE OKLAHOMA PANHANDLE...HELPING TO FOCUS
THE BETTER MOISTURE OVER THE SOUTH. THE WARMER TEMPERATURES DURING
THIS TIME PERIOD WILL KEEP THE PRECIPITATION MAINLY IN THE FORM VERY
LIGHT RAIN OR DRIZZLE...HOWEVER...IT IS POSSIBLE THAT A FEW INLAND
AREAS COULD SEE LIGHT FREEZING DRIZZLE LATE SATURDAY NIGHT. WOULD
NOT EXPECT TOO MUCH OF AN IMPACT ON ROADWAYS WITH THE WARMER DAYTIME
HIGHS ACROSS THE AREA. AT THIS POINT...WENT WITH THE VERY LIGHT RAIN
MENTION...WITH DROPLETS EXPECTED TO BE FAIRLY SMALL AS MOISTURE IS
NOT DEEP ENOUGH FOR RAINFALL TO AMOUNT TO MUCH. MODELS BEGIN TO
DIVERGE ON THE PLACEMENT OF THE SOUTHERN LOW THROUGH THE REMAINING
EXTENDED WITH THE 06Z GFS BRINGING THE LOW TO THE NORTHEAST REACHING
SOUTHEASTERN LOWER MI BY MONDAY NIGHT WHILE THE EC KEEPS THE LOW
MUCH FARTHER SOUTH...AROUND SOUTHEAST MISSOURI AT THE SAME TIME. THE
LATEST...12Z MODEL RUN OF THE GFS/EC ARE IN BETTER AGREEMENT WITH
THE MORE SOUTHERLY TRACK. BOTH MODELS ALSO AGREE WITH A COLD FRONT
PUSHING THROUGH THE UPPER GREAT LAKES REGION LATE SUNDAY NIGHT INTO
MONDAY...WITH BROAD UPPER LEVEL TROUGHING PUSHING ACROSS THE AREA
MONDAY NIGHT INTO TUESDAY ALLOWING TEMPERATURES TO COOL ONCE AGAIN.
THIS WILL ALSO ALLOW THE PRECIPITATION TO TRANSITION BACK TO SNOW
FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA. ADDITIONALLY...WITH THE
COOLER AIR PUSHING INTO THE AREA AND 850MB TEMPS FALLING TO AROUND
-8 TO -10C MONDAY NIGHT INTO TUESDAY EXPECT TO SEE LIGHT LAKE EFFECT
DEVELOP...THIS WOULD BE SHORT-LIVED AS ANOTHER RIDGE BEGINS TO BUILD
ACROSS THE PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1233 PM EST TUE DEC 9 2014
A DIFFICULT LO CLD FCST IS ON TAP FOR THE TAF SITES. LINGERING LLVL
MSTR IN UPSLOPE NNE FLOW OFF LK SUP AND UNDER LOWERING SUBSIDENCE
INVRN ASSOCIATED WITH BLDG UPR RDG IS CAUSING THE LO CLDS OBSVD
TODAY. ALTHOUGH SOME NEAR SFC DRYING WL CAUSE THE CIGS TO RUN
GENERALLY IN THE MVFR RANGE...THE LO CLDS SHOULD PERSIST THRU THIS
EVNG AT ALL 3 SITES. THE BEST CHC FOR SOME CLRG AND A RETURN TO VFR
WX WL BE AT SAW AND IWD LATER TNGT AS THE LLVL FLOW VEERS SLOWLY TO
A MORE ESE DIRECTION THAT WL DOWNSLOPE INTO IWD AND LIMIT MOISTENING
OFF LK SUP INTO SAW. A MORE UPSLOPE WIND COMPONENT AND SOME
MOISTENING OFF LK SUP AT CMX WL LIKELY CAUSE THE MVFR CIGS TO LINGER
THERE THRU THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 402 PM EST TUE DEC 9 2014
HIGH PRESSURE WILL SETTLE OVER THE UPPER GREAT LAKES TONIGHT AND
LINGER THROUGH FRIDAY ALLOWING WINDS TO DROP OFF TO UNDER 15KT. THESE
LIGHTER WINDS WILL LIKELY LINGER INTO SATURDAY. LOW PRESSURE AND AN
ASSOCIATED COLD FRONT WILL PASS THROUGH THE REGION SUNDAY NIGHT
THROUGH MONDAY ALLOWING WINDS TO INCREASE ONCE AGAIN FROM THE NORTH.
AT THIS POINT WINDS ARE EXPECTED TO REMAIN BELOW 25 KNOTS SUNDAY
NIGHT THROUGH MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KEC
AVIATION...KC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
348 PM EST TUE DEC 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 346 PM EST TUE DEC 9 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR TROF
STRETCING S FM HUDSON BAY INTO THE SE CONUS DOWNSTREAM OF AN UPR RDG
IN THE PLAINS. SFC HI PRES UNDER THE THE UPR RDG STRETCHES FM NW
ONTARIO INTO MN. 12HR 00Z-12Z H5 HGT RISES IN THE 100-150M RANGE FM
YPL TO INL AND MPX INDICATE THE UPR RDG/SFC HI ARE BUILDING INTO THE
WRN GREAT LKS...BUT PLENTY OF LO CLDS/A FEW FLURRIES LINGER OVER THE
CWA EARLY THIS AFTN WITH LLVL MSTR TRAPPED IN NEAR SFC NNE FLOW OFF
LK SUP UNDER INVRN BASE THAT HAD LOWERED TO NEAR H95 BY 12Z AT INL
UNDER THE STRONG DNVA/SUBSIDENCE ASSOCIATED WITH THE INCOMING UPR
RDG. THE AIR TO THE N OF LK SUP IS QUITE A BIT DRIER PER THE 12Z YPL
RAOB...WITH SFC DEWPTS NEAR OR BLO 0F AT MOST PLACES IN ONTARIO.
SKIES ARE MOCLR THERE...AND ASSOCIATED DRYING IS TENDING TO BREAK UP
THE LO CLDS OVER THE NRN AND ERN PORTION OF LK SUP. BUT THIS CLRG IS
HAVING A HARD TIME MAKING MUCH PROGRESS TOWARD UPR MI.
MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON LO CLD TRENDS
AND IMPACT ON TEMPS.
TNGT...AS UPR RDG CONTINUES TO SHIFT SLOWLY TO THE E...SFC HI PRES
RDG IS FCST TO DRIFT SLOWLY E AS WELL...REACHING A LINE FM NEAR
JAMES BAY INTO NW WI BY 12Z WED. LOWERING INVRN BASE UNDER THE
ASSOCIATED SUBSIDENCE SHOULD END ANY LINGERING FLURRIES...BUT MODELS
HAVE TRENDED TO BE MORE PESSIMISTIC IN REGARDS TO CLEARING THE LO
CLDS...WHICH SEEMS CONSISTENT WITH RATHER SLOW OBSVD CLRG TREND.
BEST CHC FOR SOME CLRG WL BE OVER THE ERN CWA AS THE SLOWLY VEERING
LLVL FLOW TOWARD THE E WL DOWNSLOPE OFF ONTARIO AND LIMIT THE OVER
WATER TRAJECTORY. ONE OTHER AREA WHERE THERE MAY BE SOME CLRG IS
OVER THE FAR W...WHERE FLOW SHIFTING TOWARD THE SSE WL DOWNSLOPE AS
WELL. BUT THE SFC-H925 WINDS ARE FCST TO BE ONLY 5-10 KTS...SO THE
ASSOCIATED SUBSIDENCE MIGHT NOT BE SUFFICIENT TO BREAK UP THE LO
CLDS SIGNIFICANTLY. WL TEND TOWARD THE LOWEST MIN TEMPS OVER THE
INTERIOR E...WITH LINGERING CLDS HOLDING UP THE TEMPS ELSEWHERE.
WED...SFC HI PRES RDG AXIS IS PROGGED TO DRIFT ONLY SLOWLY E THRU
THE DAY...REMAINING OVER CENTRAL UPR MI THRU THE DAY. WITH CONTINUED
SUBSIDENCE...EXPECT LINGERING LO CLDS TO SLOWLY BREAK UP. THESE CLDS
SHOULD BE MOST PERSISTENT OVER THE HIER TERRAIN OF THE CENTRAL
CWA...BUT EVEN HERE THE CLDS SHOULD BREAK UP AS THE SUBSIDENCE INVRN
SINKS TO THE NEAR THE SFC AS SHOWN ON FCST SDNGS. TENDED TOWARD THE
LO END OF GUIDANCE FOR MAX TEMPS GIVEN HI STABILITY SHOWN ON FCST
SDNGS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EST TUE DEC 9 2014
AN UPPER RIDGE WILL BUILD OVER THE CWA THROUGH SAT AS A SFC RIDGE
SITS OVER THE CWA BEFORE MOVING SE FRI INTO SAT. THIS WILL KEEP
CONDITIONS ON THE QUIET SIDE WITH NO PRECIP EXPECTED THROUGH 00Z
SUN. WED NIGHT LOOKS TO BE THE COLDEST NIGHT WITH SINGLE DIGIT ABOVE
ZERO LOWS INLAND AS THE RIDGE WILL BE OVERHEAD AND THE SIGNIFICANTLY
WARMER AIRMASS IS STILL TO THE W. 850MB TEMPS WILL BE ON THE RISE
FROM AOB 0C AT 12Z WED TO AOA 10C BY 00Z SAT...WITH THE WARMER TEMPS
STICKING AROUND THROUGH SAT. WARMEST TEMPS EXPECTED ON SAT WITH
HIGHS FROM THE UPPER 30S TO LOW 40S.
WHILE THERE IS A LOT OF UNCERTAINTY WITH THE TRANSITION INTO A MORE
ACTIVE PATTER LATE IN THE WEEKEND...IT DOES LOOK LIKE SOME LIGHT
PRECIP IS POSSIBLE SOMETIME SUN INTO MON...AND PTYPE WILL TRANSITION
BACK TO SNOW AT LEAST OVER PORTIONS OF THE AREA BY MON. LOTS WILL
DEPEND ON THE TRACK/STRENGTH OF UPPER LEVEL ENERGY WHICH MODELS VARY
SUBSTANTIALLY FROM RUN TO RUN. STILL NOT BUYING GREATER QPF/LOW
LEVEL MOISTURE THAT MODELS SHOW ON SUN/SUN NIGHT AS MODELS LIKELY
ARE OVERDOING LOW LEVEL MOISTURE AS THEY OFTEN DO WHEN MODELING
SNOWPACK MELTING. REMOVED ANY MENTION OF FREEZING RAIN FOR SAT
NIGHT-MON SINCE SFC TEMPS WILL BE TOO WARM FOR FREEZING RAIN IF THE
RAIN/CLOUDS ARE AS THICK AS MODELS SUGGEST...AND IF THERE IS LESS
LOW LEVEL MOISTURE TEMPS WILL BE COLDER BUT PRECIPITATION PROBABLY
WILL NOT OCCUR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1233 PM EST TUE DEC 9 2014
A DIFFICULT LO CLD FCST IS ON TAP FOR THE TAF SITES. LINGERING LLVL
MSTR IN UPSLOPE NNE FLOW OFF LK SUP AND UNDER LOWERING SUBSIDENCE
INVRN ASSOCIATED WITH BLDG UPR RDG IS CAUSING THE LO CLDS OBSVD
TODAY. ALTHOUGH SOME NEAR SFC DRYING WL CAUSE THE CIGS TO RUN
GENERALLY IN THE MVFR RANGE...THE LO CLDS SHOULD PERSIST THRU THIS
EVNG AT ALL 3 SITES. THE BEST CHC FOR SOME CLRG AND A RETURN TO VFR
WX WL BE AT SAW AND IWD LATER TNGT AS THE LLVL FLOW VEERS SLOWLY TO
A MORE ESE DIRECTION THAT WL DOWNSLOPE INTO IWD AND LIMIT MOISTENING
OFF LK SUP INTO SAW. A MORE UPSLOPE WIND COMPONENT AND SOME
MOISTENING OFF LK SUP AT CMX WL LIKELY CAUSE THE MVFR CIGS TO LINGER
THERE THRU THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 512 AM EST TUE DEC 9 2014
BEHIND A LOW PRES TROF...N TO NW WINDS RAMPED UP TO 20-30KT
OVERNIGHT WITH A FEW GALE FORCE GUSTS NOTED OVER CNTRL LAKE
SUPERIOR. AS HIGH PRES RIDGE EXTENDING FROM THE NRN PLAINS TO HUDSON
BAY APPROACHES TODAY...WINDS WILL DIMINISH FROM W TO E TO UNDER 20KT
BY EVENING. WITH THE HIGH PRES RIDGE THEN SETTLING OVER THE UPPER
LAKES TONIGHT THRU WED...WINDS WILL DROP OFF TO UNDER 15KT. WINDS
WILL INCREASE SLIGHTLY THU AND FRI...BUT WILL REMAIN UNDER 20KT.
THESE LIGHTER WINDS MAY LINGER ON INTO SAT AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1235 PM EST TUE DEC 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 512 AM EST TUE DEC 9 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF EXTENDING FROM HUDSON
BAY S THRU THE OHIO VALLEY. WITH TROF AXIS NOW E OF UPPER MI...
HEIGHTS ARE BEGINNING TO RISE AS BROAD RIDGE OVER WRN NAMERICA
EXPANDS EASTWARD. AT THE SFC...TROF IS ALSO NOW S AND E OF UPPER MI
WITH BRISK N TO NW WINDS USHERING IN SOMEWHAT COLDER AIR INTO THE
AREA...MOST NOTICEABLE BLO 850MB. WITH ABUNDANT LOW-LEVEL MOISTURE
PER UPSTREAM 00Z KINL/CWPL SOUNDINGS...LOW CLOUDS ARE WIDESPREAD
OVER THE UPPER LAKES WITH CLEARING ONLY NOTED OVER PORTIONS OF NRN
AND WRN LAKE SUPERIOR IN THE DOWNSLOPE AREAS OFF ONTARIO AND MN
NSHORE. TEMPS IN THE SHALLOW MOIST LAYER HAVE BEEN FALLING...BUT
APPARENTLY AREN`T COLD ENOUGH YET TO ENSURE COMPLETE ICE NUCLEATION
AS -SN HAS BEEN MIXED AT TIMES WITH -FZDZ DURING THE NIGHT IN THE
UPSLOPE FLOW OFF LAKE SUPERIOR. LATEST RUC/NAM FCST SOUNDINGS SHOW
TEMPS IN THE MOIST LAYER NEARING -10C...SO ANY LINGERING -FZDZ
SHOULD BE ENDING IN THE NEXT FEW HRS. A FEW HRS AGO...ONLY ONE
HEAVIER BAND OF SNOW WAS NOTED OFF SCNTRL LAKE SUPERIOR INTO THE
MARQUETTE AREA AND ERN MARQUETTE COUNTY. CURRENTLY...RADAR DOES NOT
SHOW ANYTHING OTHER THAN VERY LIGHT PCPN STREAMERS.
LINGERING -SHSN/FLURRIES WILL WIND DOWN TODAY AS INVERSION FALLS TO
2-3KFT AHEAD OF A 1035-1040MB HIGH PRES RIDGE DRIFTING SE TOWARD THE
UPPER LAKES. WITH THE ABUNDANT LOW-LEVEL MOISTURE NOTED OVER THE
REGION UNDER INVERSION...OPTED TOWARD A MUCH MORE PESSIMISTIC CLOUD
FCST TODAY. CLOUDS WILL BE MOST RELUCTANT TO BREAK IN THE AREAS
WHERE N TO NE FLOW IS UPSLOPING. BREAKING OF THE CLOUDS MAY BE MORE
LIKELY OVER THE FAR E LATER IN THE DAY AS VEERING WINDS INCREASE
DOWNSLOPING OFF ONTARIO. MAY SEE A SIMILAR SITUATION NEAR LAKE
SUPERIOR OVER THE FAR W LATE AS DOWNSLOPING BEGINS WITH WINDS
VEERING MORE EASTERLY. CLOUDS/SHALLOW CAA WILL KEEP TEMPS FROM
RISING MUCH DURING THE DAY.
SFC HIGH PRES RIDGE AXIS WILL SETTLE OVER UPPER MI/LAKE SUPERIOR
TONIGHT. WHILE FAVORABLE FOR A GOOD RADIATIONAL COOLING NIGHT...
THERE IS HUGE BUST POTENTIAL WITH TEMPS DUE TO UNCERTAINTY IN CLOUD
COVER. BEST BET FOR CLEARING IS IN TWO AREAS. CLEARING SHOULD EXPAND
WESTWARD THRU ERN UPPER MI FROM THE DOWNSLOPING OFF ONTARIO UNDER E
TO NE FLOW...AND CLEARING WILL ALSO EXPAND NEAR LAKE SUPERIOR OVER
WRN UPPER MI AS WINDS BECOME DOWNSLOPING E TO SE. NCNTRL UPPER MI
INTO THE KEWEENAW WILL LIKELY SEE MOST PERSISTENT CLOUD COVER
TONIGHT AS WINDS MAINTAIN SOME UPSLOPE COMPONENT ALL NIGHT. FOR
NOW...INDICATED MIN TEMPS INTO THE SINGLE DIGITS WHERE AT LEAST SOME
CLEARING IS EXPECTED. IF SKIES CLEAR...TRADITIONAL COLD SPOTS WILL
FALL TO NEAR OR PERHAPS BLO 0F. IF CLOUDS HOLD...TEENS WILL LIKELY
BE THE RULE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EST TUE DEC 9 2014
AN UPPER RIDGE WILL BUILD OVER THE CWA THROUGH SAT AS A SFC RIDGE
SITS OVER THE CWA BEFORE MOVING SE FRI INTO SAT. THIS WILL KEEP
CONDITIONS ON THE QUIET SIDE WITH NO PRECIP EXPECTED THROUGH 00Z
SUN. WED NIGHT LOOKS TO BE THE COLDEST NIGHT WITH SINGLE DIGIT ABOVE
ZERO LOWS INLAND AS THE RIDGE WILL BE OVERHEAD AND THE SIGNIFICANTLY
WARMER AIRMASS IS STILL TO THE W. 850MB TEMPS WILL BE ON THE RISE
FROM AOB 0C AT 12Z WED TO AOA 10C BY 00Z SAT...WITH THE WARMER TEMPS
STICKING AROUND THROUGH SAT. WARMEST TEMPS EXPECTED ON SAT WITH
HIGHS FROM THE UPPER 30S TO LOW 40S.
WHILE THERE IS A LOT OF UNCERTAINTY WITH THE TRANSITION INTO A MORE
ACTIVE PATTER LATE IN THE WEEKEND...IT DOES LOOK LIKE SOME LIGHT
PRECIP IS POSSIBLE SOMETIME SUN INTO MON...AND PTYPE WILL TRANSITION
BACK TO SNOW AT LEAST OVER PORTIONS OF THE AREA BY MON. LOTS WILL
DEPEND ON THE TRACK/STRENGTH OF UPPER LEVEL ENERGY WHICH MODELS VARY
SUBSTANTIALLY FROM RUN TO RUN. STILL NOT BUYING GREATER QPF/LOW
LEVEL MOISTURE THAT MODELS SHOW ON SUN/SUN NIGHT AS MODELS LIKELY
ARE OVERDOING LOW LEVEL MOISTURE AS THEY OFTEN DO WHEN MODELING
SNOWPACK MELTING. REMOVED ANY MENTION OF FREEZING RAIN FOR SAT
NIGHT-MON SINCE SFC TEMPS WILL BE TOO WARM FOR FREEZING RAIN IF THE
RAIN/CLOUDS ARE AS THICK AS MODELS SUGGEST...AND IF THERE IS LESS
LOW LEVEL MOISTURE TEMPS WILL BE COLDER BUT PRECIPITATION PROBABLY
WILL NOT OCCUR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1233 PM EST TUE DEC 9 2014
A DIFFICULT LO CLD FCST IS ON TAP FOR THE TAF SITES. LINGERING LLVL
MSTR IN UPSLOPE NNE FLOW OFF LK SUP AND UNDER LOWERING SUBSIDENCE
INVRN ASSOCIATED WITH BLDG UPR RDG IS CAUSING THE LO CLDS OBSVD
TODAY. ALTHOUGH SOME NEAR SFC DRYING WL CAUSE THE CIGS TO RUN
GENERALLY IN THE MVFR RANGE...THE LO CLDS SHOULD PERSIST THRU THIS
EVNG AT ALL 3 SITES. THE BEST CHC FOR SOME CLRG AND A RETURN TO VFR
WX WL BE AT SAW AND IWD LATER TNGT AS THE LLVL FLOW VEERS SLOWLY TO
A MORE ESE DIRECTION THAT WL DOWNSLOPE INTO IWD AND LIMIT MOISTENING
OFF LK SUP INTO SAW. A MORE UPSLOPE WIND COMPONENT AND SOME
MOISTENING OFF LK SUP AT CMX WL LIKELY CAUSE THE MVFR CIGS TO LINGER
THERE THRU THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 512 AM EST TUE DEC 9 2014
BEHIND A LOW PRES TROF...N TO NW WINDS RAMPED UP TO 20-30KT
OVERNIGHT WITH A FEW GALE FORCE GUSTS NOTED OVER CNTRL LAKE
SUPERIOR. AS HIGH PRES RIDGE EXTENDING FROM THE NRN PLAINS TO HUDSON
BAY APPROACHES TODAY...WINDS WILL DIMINISH FROM W TO E TO UNDER 20KT
BY EVENING. WITH THE HIGH PRES RIDGE THEN SETTLING OVER THE UPPER
LAKES TONIGHT THRU WED...WINDS WILL DROP OFF TO UNDER 15KT. WINDS
WILL INCREASE SLIGHTLY THU AND FRI...BUT WILL REMAIN UNDER 20KT.
THESE LIGHTER WINDS MAY LINGER ON INTO SAT AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
631 AM EST TUE DEC 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 512 AM EST TUE DEC 9 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF EXTENDING FROM HUDSON
BAY S THRU THE OHIO VALLEY. WITH TROF AXIS NOW E OF UPPER MI...
HEIGHTS ARE BEGINNING TO RISE AS BROAD RIDGE OVER WRN NAMERICA
EXPANDS EASTWARD. AT THE SFC...TROF IS ALSO NOW S AND E OF UPPER MI
WITH BRISK N TO NW WINDS USHERING IN SOMEWHAT COLDER AIR INTO THE
AREA...MOST NOTICEABLE BLO 850MB. WITH ABUNDANT LOW-LEVEL MOISTURE
PER UPSTREAM 00Z KINL/CWPL SOUNDINGS...LOW CLOUDS ARE WIDESPREAD
OVER THE UPPER LAKES WITH CLEARING ONLY NOTED OVER PORTIONS OF NRN
AND WRN LAKE SUPERIOR IN THE DOWNSLOPE AREAS OFF ONTARIO AND MN
NSHORE. TEMPS IN THE SHALLOW MOIST LAYER HAVE BEEN FALLING...BUT
APPARENTLY AREN`T COLD ENOUGH YET TO ENSURE COMPLETE ICE NUCLEATION
AS -SN HAS BEEN MIXED AT TIMES WITH -FZDZ DURING THE NIGHT IN THE
UPSLOPE FLOW OFF LAKE SUPERIOR. LATEST RUC/NAM FCST SOUNDINGS SHOW
TEMPS IN THE MOIST LAYER NEARING -10C...SO ANY LINGERING -FZDZ
SHOULD BE ENDING IN THE NEXT FEW HRS. A FEW HRS AGO...ONLY ONE
HEAVIER BAND OF SNOW WAS NOTED OFF SCNTRL LAKE SUPERIOR INTO THE
MARQUETTE AREA AND ERN MARQUETTE COUNTY. CURRENTLY...RADAR DOES NOT
SHOW ANYTHING OTHER THAN VERY LIGHT PCPN STREAMERS.
LINGERING -SHSN/FLURRIES WILL WIND DOWN TODAY AS INVERSION FALLS TO
2-3KFT AHEAD OF A 1035-1040MB HIGH PRES RIDGE DRIFTING SE TOWARD THE
UPPER LAKES. WITH THE ABUNDANT LOW-LEVEL MOISTURE NOTED OVER THE
REGION UNDER INVERSION...OPTED TOWARD A MUCH MORE PESSIMISTIC CLOUD
FCST TODAY. CLOUDS WILL BE MOST RELUCTANT TO BREAK IN THE AREAS
WHERE N TO NE FLOW IS UPSLOPING. BREAKING OF THE CLOUDS MAY BE MORE
LIKELY OVER THE FAR E LATER IN THE DAY AS VEERING WINDS INCREASE
DOWNSLOPING OFF ONTARIO. MAY SEE A SIMILAR SITUATION NEAR LAKE
SUPERIOR OVER THE FAR W LATE AS DOWNSLOPING BEGINS WITH WINDS
VEERING MORE EASTERLY. CLOUDS/SHALLOW CAA WILL KEEP TEMPS FROM
RISING MUCH DURING THE DAY.
SFC HIGH PRES RIDGE AXIS WILL SETTLE OVER UPPER MI/LAKE SUPERIOR
TONIGHT. WHILE FAVORABLE FOR A GOOD RADIATIONAL COOLING NIGHT...
THERE IS HUGE BUST POTENTIAL WITH TEMPS DUE TO UNCERTAINTY IN CLOUD
COVER. BEST BET FOR CLEARING IS IN TWO AREAS. CLEARING SHOULD EXPAND
WESTWARD THRU ERN UPPER MI FROM THE DOWNSLOPING OFF ONTARIO UNDER E
TO NE FLOW...AND CLEARING WILL ALSO EXPAND NEAR LAKE SUPERIOR OVER
WRN UPPER MI AS WINDS BECOME DOWNSLOPING E TO SE. NCNTRL UPPER MI
INTO THE KEWEENAW WILL LIKELY SEE MOST PERSISTENT CLOUD COVER
TONIGHT AS WINDS MAINTAIN SOME UPSLOPE COMPONENT ALL NIGHT. FOR
NOW...INDICATED MIN TEMPS INTO THE SINGLE DIGITS WHERE AT LEAST SOME
CLEARING IS EXPECTED. IF SKIES CLEAR...TRADITIONAL COLD SPOTS WILL
FALL TO NEAR OR PERHAPS BLO 0F. IF CLOUDS HOLD...TEENS WILL LIKELY
BE THE RULE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EST TUE DEC 9 2014
AN UPPER RIDGE WILL BUILD OVER THE CWA THROUGH SAT AS A SFC RIDGE
SITS OVER THE CWA BEFORE MOVING SE FRI INTO SAT. THIS WILL KEEP
CONDITIONS ON THE QUIET SIDE WITH NO PRECIP EXPECTED THROUGH 00Z
SUN. WED NIGHT LOOKS TO BE THE COLDEST NIGHT WITH SINGLE DIGIT ABOVE
ZERO LOWS INLAND AS THE RIDGE WILL BE OVERHEAD AND THE SIGNIFICANTLY
WARMER AIRMASS IS STILL TO THE W. 850MB TEMPS WILL BE ON THE RISE
FROM AOB 0C AT 12Z WED TO AOA 10C BY 00Z SAT...WITH THE WARMER TEMPS
STICKING AROUND THROUGH SAT. WARMEST TEMPS EXPECTED ON SAT WITH
HIGHS FROM THE UPPER 30S TO LOW 40S.
WHILE THERE IS A LOT OF UNCERTAINTY WITH THE TRANSITION INTO A MORE
ACTIVE PATTER LATE IN THE WEEKEND...IT DOES LOOK LIKE SOME LIGHT
PRECIP IS POSSIBLE SOMETIME SUN INTO MON...AND PTYPE WILL TRANSITION
BACK TO SNOW AT LEAST OVER PORTIONS OF THE AREA BY MON. LOTS WILL
DEPEND ON THE TRACK/STRENGTH OF UPPER LEVEL ENERGY WHICH MODELS VARY
SUBSTANTIALLY FROM RUN TO RUN. STILL NOT BUYING GREATER QPF/LOW
LEVEL MOISTURE THAT MODELS SHOW ON SUN/SUN NIGHT AS MODELS LIKELY
ARE OVERDOING LOW LEVEL MOISTURE AS THEY OFTEN DO WHEN MODELING
SNOWPACK MELTING. REMOVED ANY MENTION OF FREEZING RAIN FOR SAT
NIGHT-MON SINCE SFC TEMPS WILL BE TOO WARM FOR FREEZING RAIN IF THE
RAIN/CLOUDS ARE AS THICK AS MODELS SUGGEST...AND IF THERE IS LESS
LOW LEVEL MOISTURE TEMPS WILL BE COLDER BUT PRECIPITATION PROBABLY
WILL NOT OCCUR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 631 AM EST TUE DEC 9 2014
ABUNDANT LOW-LEVEL MOISTURE TRAPPED UNDER FALLING SUBSIDENCE
INVERSION WILL SET THE STAGE FOR A CHALLENGING FCST. INITIALLY...
UPSLOPE FLOW OFF LAKE SUPERIOR WILL CONTINUE TO SUPPORT PREVAILING
LIFR CIGS AT KIWD/KCMX/KSAW FOR MUCH OF THE MORNING. EXPECT SLOW
IMPROVEMENT TO IFR...THEN LOW MVFR DURING THE AFTN AS SLIGHT DRYING
OCCURS IN THE LOW-LEVELS. AS DOWNSLOPING BEGINS AT KIWD WITH
LOW-LEVEL WINDS VEERING TO LIGHT E TO SE THIS EVENING...LOW MVFR
CIGS SHOULD SCATTER OUT. CLEARING SHOULD ALSO PROGRESS W THRU ERN
UPPER MI...AND IT`S POSSIBLE LOW MVFR CIGS COULD SCATTER OUT AT KSAW
LATE TONIGHT. WITH MOSTLY A LIGHT UPSLOPE FLOW CONTINUING AT KCMX...
LOW MVFR CIGS MAY PERSIST THRU THE NIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 512 AM EST TUE DEC 9 2014
BEHIND A LOW PRES TROF...N TO NW WINDS RAMPED UP TO 20-30KT
OVERNIGHT WITH A FEW GALE FORCE GUSTS NOTED OVER CNTRL LAKE
SUPERIOR. AS HIGH PRES RIDGE EXTENDING FROM THE NRN PLAINS TO HUDSON
BAY APPROACHES TODAY...WINDS WILL DIMINISH FROM W TO E TO UNDER 20KT
BY EVENING. WITH THE HIGH PRES RIDGE THEN SETTLING OVER THE UPPER
LAKES TONIGHT THRU WED...WINDS WILL DROP OFF TO UNDER 15KT. WINDS
WILL INCREASE SLIGHTLY THU AND FRI...BUT WILL REMAIN UNDER 20KT.
THESE LIGHTER WINDS MAY LINGER ON INTO SAT AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
513 AM EST TUE DEC 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 512 AM EST TUE DEC 9 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF EXTENDING FROM HUDSON
BAY S THRU THE OHIO VALLEY. WITH TROF AXIS NOW E OF UPPER MI...
HEIGHTS ARE BEGINNING TO RISE AS BROAD RIDGE OVER WRN NAMERICA
EXPANDS EASTWARD. AT THE SFC...TROF IS ALSO NOW S AND E OF UPPER MI
WITH BRISK N TO NW WINDS USHERING IN SOMEWHAT COLDER AIR INTO THE
AREA...MOST NOTICEABLE BLO 850MB. WITH ABUNDANT LOW-LEVEL MOISTURE
PER UPSTREAM 00Z KINL/CWPL SOUNDINGS...LOW CLOUDS ARE WIDESPREAD
OVER THE UPPER LAKES WITH CLEARING ONLY NOTED OVER PORTIONS OF NRN
AND WRN LAKE SUPERIOR IN THE DOWNSLOPE AREAS OFF ONTARIO AND MN
NSHORE. TEMPS IN THE SHALLOW MOIST LAYER HAVE BEEN FALLING...BUT
APPARENTLY AREN`T COLD ENOUGH YET TO ENSURE COMPLETE ICE NUCLEATION
AS -SN HAS BEEN MIXED AT TIMES WITH -FZDZ DURING THE NIGHT IN THE
UPSLOPE FLOW OFF LAKE SUPERIOR. LATEST RUC/NAM FCST SOUNDINGS SHOW
TEMPS IN THE MOIST LAYER NEARING -10C...SO ANY LINGERING -FZDZ
SHOULD BE ENDING IN THE NEXT FEW HRS. A FEW HRS AGO...ONLY ONE
HEAVIER BAND OF SNOW WAS NOTED OFF SCNTRL LAKE SUPERIOR INTO THE
MARQUETTE AREA AND ERN MARQUETTE COUNTY. CURRENTLY...RADAR DOES NOT
SHOW ANYTHING OTHER THAN VERY LIGHT PCPN STREAMERS.
LINGERING -SHSN/FLURRIES WILL WIND DOWN TODAY AS INVERSION FALLS TO
2-3KFT AHEAD OF A 1035-1040MB HIGH PRES RIDGE DRIFTING SE TOWARD THE
UPPER LAKES. WITH THE ABUNDANT LOW-LEVEL MOISTURE NOTED OVER THE
REGION UNDER INVERSION...OPTED TOWARD A MUCH MORE PESSIMISTIC CLOUD
FCST TODAY. CLOUDS WILL BE MOST RELUCTANT TO BREAK IN THE AREAS
WHERE N TO NE FLOW IS UPSLOPING. BREAKING OF THE CLOUDS MAY BE MORE
LIKELY OVER THE FAR E LATER IN THE DAY AS VEERING WINDS INCREASE
DOWNSLOPING OFF ONTARIO. MAY SEE A SIMILAR SITUATION NEAR LAKE
SUPERIOR OVER THE FAR W LATE AS DOWNSLOPING BEGINS WITH WINDS
VEERING MORE EASTERLY. CLOUDS/SHALLOW CAA WILL KEEP TEMPS FROM
RISING MUCH DURING THE DAY.
SFC HIGH PRES RIDGE AXIS WILL SETTLE OVER UPPER MI/LAKE SUPERIOR
TONIGHT. WHILE FAVORABLE FOR A GOOD RADIATIONAL COOLING NIGHT...
THERE IS HUGE BUST POTENTIAL WITH TEMPS DUE TO UNCERTAINTY IN CLOUD
COVER. BEST BET FOR CLEARING IS IN TWO AREAS. CLEARING SHOULD EXPAND
WESTWARD THRU ERN UPPER MI FROM THE DOWNSLOPING OFF ONTARIO UNDER E
TO NE FLOW...AND CLEARING WILL ALSO EXPAND NEAR LAKE SUPERIOR OVER
WRN UPPER MI AS WINDS BECOME DOWNSLOPING E TO SE. NCNTRL UPPER MI
INTO THE KEWEENAW WILL LIKELY SEE MOST PERSISTENT CLOUD COVER
TONIGHT AS WINDS MAINTAIN SOME UPSLOPE COMPONENT ALL NIGHT. FOR
NOW...INDICATED MIN TEMPS INTO THE SINGLE DIGITS WHERE AT LEAST SOME
CLEARING IS EXPECTED. IF SKIES CLEAR...TRADITIONAL COLD SPOTS WILL
FALL TO NEAR OR PERHAPS BLO 0F. IF CLOUDS HOLD...TEENS WILL LIKELY
BE THE RULE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EST TUE DEC 9 2014
AN UPPER RIDGE WILL BUILD OVER THE CWA THROUGH SAT AS A SFC RIDGE
SITS OVER THE CWA BEFORE MOVING SE FRI INTO SAT. THIS WILL KEEP
CONDITIONS ON THE QUIET SIDE WITH NO PRECIP EXPECTED THROUGH 00Z
SUN. WED NIGHT LOOKS TO BE THE COLDEST NIGHT WITH SINGLE DIGIT ABOVE
ZERO LOWS INLAND AS THE RIDGE WILL BE OVERHEAD AND THE SIGNIFICANTLY
WARMER AIRMASS IS STILL TO THE W. 850MB TEMPS WILL BE ON THE RISE
FROM AOB 0C AT 12Z WED TO AOA 10C BY 00Z SAT...WITH THE WARMER TEMPS
STICKING AROUND THROUGH SAT. WARMEST TEMPS EXPECTED ON SAT WITH
HIGHS FROM THE UPPER 30S TO LOW 40S.
WHILE THERE IS A LOT OF UNCERTAINTY WITH THE TRANSITION INTO A MORE
ACTIVE PATTER LATE IN THE WEEKEND...IT DOES LOOK LIKE SOME LIGHT
PRECIP IS POSSIBLE SOMETIME SUN INTO MON...AND PTYPE WILL TRANSITION
BACK TO SNOW AT LEAST OVER PORTIONS OF THE AREA BY MON. LOTS WILL
DEPEND ON THE TRACK/STRENGTH OF UPPER LEVEL ENERGY WHICH MODELS VARY
SUBSTANTIALLY FROM RUN TO RUN. STILL NOT BUYING GREATER QPF/LOW
LEVEL MOISTURE THAT MODELS SHOW ON SUN/SUN NIGHT AS MODELS LIKELY
ARE OVERDOING LOW LEVEL MOISTURE AS THEY OFTEN DO WHEN MODELING
SNOWPACK MELTING. REMOVED ANY MENTION OF FREEZING RAIN FOR SAT
NIGHT-MON SINCE SFC TEMPS WILL BE TOO WARM FOR FREEZING RAIN IF THE
RAIN/CLOUDS ARE AS THICK AS MODELS SUGGEST...AND IF THERE IS LESS
LOW LEVEL MOISTURE TEMPS WILL BE COLDER BUT PRECIPITATION PROBABLY
WILL NOT OCCUR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1242 AM EST TUE DEC 9 2014
LOW-LEVEL MOISTURE IN THE WAKE OF LOW PRESSURE MOVING OVER EASTERN
UPR MICHIGAN IS COMBINING WITH UPSLOPE FLOW TO MAINTAIN LIFR/IFR
CIGS AT ALL THE TAF SITES. EXPECT MVFR OR IFR VSBY OVERNIGHT WITH
SOME LGT SNOW SHOWERS OR EVEN DZ/FZDZ. IMPROVEMENT EXPECTED AT KCMX
LATE IN THE NIGHT AS UPSLOPING DIMINISHES. ADDITIONAL IMPROVEMENT WILL
OCCUR AT ALL THE TAF SITES TODAY BUT BKN-OVC MVFR CIGS SHOULD REMAIN
IN PLACE INTO THE EVENING AS MOISTURE REMAINS TRAPPED BENEATH
INVERSION. HOWEVER...SKIES SHOULD AT LEAST PARTIALLY CLEAR OUT AT
KIWD BY AFTN AS DOWNSLOPING EAST FLOW DEVELOPS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 512 AM EST TUE DEC 9 2014
BEHIND A LOW PRES TROF...N TO NW WINDS RAMPED UP TO 20-30KT
OVERNIGHT WITH A FEW GALE FORCE GUSTS NOTED OVER CNTRL LAKE
SUPERIOR. AS HIGH PRES RIDGE EXTENDING FROM THE NRN PLAINS TO HUDSON
BAY APPROACHES TODAY...WINDS WILL DIMINISH FROM W TO E TO UNDER 20KT
BY EVENING. WITH THE HIGH PRES RIDGE THEN SETTLING OVER THE UPPER
LAKES TONIGHT THRU WED...WINDS WILL DROP OFF TO UNDER 15KT. WINDS
WILL INCREASE SLIGHTLY THU AND FRI...BUT WILL REMAIN UNDER 20KT.
THESE LIGHTER WINDS MAY LINGER ON INTO SAT AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JLA
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
347 AM EST TUE DEC 9 2014
.UPDATE...
ISSUED AT 713 PM EST MON DEC 8 2014
LOW PRESSURE SLIDING OVER CNTRL UPR MICHIGAN AS OF 23Z. COLD AIR IN
WAKE OF THE LOW SLOW TO ARRIVE. DEEP MOISTURE TIED INTO THE LOW HAS
FADED QUICKLY AND LEFTOVER MOISTURE IS SHALLOW IN DEPTH AND TEMPS
WITHIN THE MOIST LAYER ARE ONLY AS COOL AS -4C TO -6C OVER WESTERN
LK SUPERIOR AND WESTERN CWA. VSBY AT IWD AND CMX HAS BEEN BLO 5SM
SINCE SUNSET. REPORTS FM SOCIAL MEDIA INDICATE DRIZZLE OCCURRING
OVER KEWEENAW AND LOWER ELEVATIONS OF ONTONAGON COUNTY. SOME SNOW
FLURRIES ARE FALLING OVER HIGHER TERRAIN IN ONTONAGON COUNTY. ADDED
PATCHY DZ/FZDZ TO GRIDS UNTIL AROUND 06Z FOR WEST/NORTHWEST AND INTO
NCNTRL. RAP/NAM/GFS SOUNDINGS INDICATE AFTER 06Z IT BECOMES COLD
ENOUGH FOR MIXED PRECIP TO CHANGE TO MAINLY SNOW.
ADDED FOG TO MUCH OF EAST HALF OF CWA THROUGH THE EVENING WITH
SOUTHERLY FLOW OVER LK MICHIGAN PUSHING DWPNTS IN LOW 30S OVER THE
WET SNOW PACK FM THE SNOW THAT OCCURRED EARLIER TODAY. ALREADY SEEING
VSBY BLO 2SM OVER MOST OF THE EAST PART OF THE CWA...INCLUDING VSBY
DOWN TO 1/4SM IN THE LAST HOUR AT MNM. ONCE WINDS IN BLYR SHIFT TO NW
LATER THIS EVENING...FOG SHOULD BEGIN TO LIFT AS MOISTENING FLOW OFF
LK MICHIGAN WILL BE DIMINISHED.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 304 PM EST MON DEC 8 2014
LATEST WATER VAPOR IMAGERY AND RUC ANALYSIS THE SHOW SHORTWAVE TROF
MOVING ACROSS THE UPPER GREAT LAKES THIS AFTERNOON. MODELS INDICATE
BEST ISENTROPIC ASCENT...MOISTURE TRANSPORT AND DEEP LAYER Q-VECT
CONVERGENCE HAS SHIFTED EAST WITH MAIN SNOW BAND AHEAD OF THE SFC-8H
TROF OVER CENTRAL UPPER MI. IT/S POSSIBLE THERE MAY BE SOME PATCHY
-FZDZ LATE THIS AFTERNOON BEHIND THE SNOW BAND WITH MID-LVL DRYING
AND LOW-LVL MOISTURE TOO SHALLOW TO REACH THE -10C ISOTHERM...BUT
NOT SURE IF THE FZDZ WILL BE SIGNIFICANT ENOUGH TO INCLUDE IN FCST
GRIDS THIS EVENING.
MODELS INDICATE THAT N TO NW WINDS WILL STRENGTHEN TONIGHT BEHIND
DEPARTING LOW PRES TONIGHT. COOLING LOW-LEVEL AIR MASS MAY SUPPORT
SOME LAKE ENHANCED SNOW FOR A BRIEF TIME THIS EVENING.
HOWEVER...SNOWFALL IS EXPECTED TO BE LIGHT FOR THE FOLLOWING
REASONS...850MB TEMPS (AROUND -6C) ARE MARGINAL FOR ENHANCEMENT
WHILE DEEPER MOISTURE IS AROUND...LOW-LEVEL FLOW IS NOT STRONGLY
CYCLONIC...AND DGZ IS ABOVE THE UPWARD MOTION AND THE DEEPER
MOISTURE. UPSLOPE/OROGRAPHIC MOTION MAY BE THE DRIVING COMPONENT
AIDING SNOWFALL...AND WHERE THAT IS MAXIMIZED...EXPECT GENERALLY 1-2
INCHES OF SNOW TONIGHT OVER HIGHER TERRAIN NEAR LAKE SUPERIOR.
INCREASED SUBSIDENCE AND LOWERING OF INVERSION HGTS AHEAD OF THE
BUILDING MID-LVL RDG UPSTREAM MAY ALSO CONTRIBUTE TO A BRIEF PD OF
UPSLOPE FZDZ LATE TONIGHT OVER THE NRN TIER COUNTIES IN NRLY FLOW
LATE TONIGHT...BUT NAM SNDGS SHOW THE SHALLOW MOIST LAYER COOLING TO
-10C BY SUNRISE WHICH SHOULD AGAIN SUPPORT MAINLY LIGHT
SNOW/FLURRIES. SINCE FZDZ THREAT IS UNCERTAIN AND LOOKS TO BE BRIEF
IF IT DOES OCCUR WL LEAVE IT OUT OF GRIDS FOR NOW. LOOK FOR MIN
TEMPS RANGING FROM THE LOWER 20S INTERIOR WEST TO UPPER 20S EAST
HALF.
1034 MB SFC RIDGE BUILDING IN FROM THE WEST SHOULD WEAKEN THE PRES
GRADIENT AND THUS ALLOW NRLY WINDS TO DIMINISH ACROSS THE AREA BY
AFTERNOON. CONTINUED LOWERING OF INVERSION BASES BLO 3KFT WILL
QUICKLY DIMINISH ANY REMAINING LIGHT UPSLOPE SHSN TO FLURRIES BY
LATE MORNING. LOOK FOR HIGHS RANGING FROM THE LOWER TO MID 20S WEST
TO LOWER 30S EAST HALF.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EST TUE DEC 9 2014
AN UPPER RIDGE WILL BUILD OVER THE CWA THROUGH SAT AS A SFC RIDGE
SITS OVER THE CWA BEFORE MOVING SE FRI INTO SAT. THIS WILL KEEP
CONDITIONS ON THE QUIET SIDE WITH NO PRECIP EXPECTED THROUGH 00Z
SUN. WED NIGHT LOOKS TO BE THE COLDEST NIGHT WITH SINGLE DIGIT ABOVE
ZERO LOWS INLAND AS THE RIDGE WILL BE OVERHEAD AND THE SIGNIFICANTLY
WARMER AIRMASS IS STILL TO THE W. 850MB TEMPS WILL BE ON THE RISE
FROM AOB 0C AT 12Z WED TO AOA 10C BY 00Z SAT...WITH THE WARMER TEMPS
STICKING AROUND THROUGH SAT. WARMEST TEMPS EXPECTED ON SAT WITH
HIGHS FROM THE UPPER 30S TO LOW 40S.
WHILE THERE IS A LOT OF UNCERTAINTY WITH THE TRANSITION INTO A MORE
ACTIVE PATTER LATE IN THE WEEKEND...IT DOES LOOK LIKE SOME LIGHT
PRECIP IS POSSIBLE SOMETIME SUN INTO MON...AND PTYPE WILL TRANSITION
BACK TO SNOW AT LEAST OVER PORTIONS OF THE AREA BY MON. LOTS WILL
DEPEND ON THE TRACK/STRENGTH OF UPPER LEVEL ENERGY WHICH MODELS VARY
SUBSTANTIALLY FROM RUN TO RUN. STILL NOT BUYING GREATER QPF/LOW
LEVEL MOISTURE THAT MODELS SHOW ON SUN/SUN NIGHT AS MODELS LIKELY
ARE OVERDOING LOW LEVEL MOISTURE AS THEY OFTEN DO WHEN MODELING
SNOWPACK MELTING. REMOVED ANY MENTION OF FREEZING RAIN FOR SAT
NIGHT-MON SINCE SFC TEMPS WILL BE TOO WARM FOR FREEZING RAIN IF THE
RAIN/CLOUDS ARE AS THICK AS MODELS SUGGEST...AND IF THERE IS LESS
LOW LEVEL MOISTURE TEMPS WILL BE COLDER BUT PRECIPITATION PROBABLY
WILL NOT OCCUR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1242 AM EST TUE DEC 9 2014
LOW-LEVEL MOISTURE IN THE WAKE OF LOW PRESSURE MOVING OVER EASTERN
UPR MICHIGAN IS COMBINING WITH UPSLOPE FLOW TO MAINTAIN LIFR/IFR
CIGS AT ALL THE TAF SITES. EXPECT MVFR OR IFR VSBY OVERNIGHT WITH
SOME LGT SNOW SHOWERS OR EVEN DZ/FZDZ. IMPROVEMENT EXPECTED AT KCMX
LATE IN THE NIGHT AS UPSLOPING DIMINISHES. ADDITIONAL IMPROVEMENT WILL
OCCUR AT ALL THE TAF SITES TODAY BUT BKN-OVC MVFR CIGS SHOULD REMAIN
IN PLACE INTO THE EVENING AS MOISTURE REMAINS TRAPPED BENEATH
INVERSION. HOWEVER...SKIES SHOULD AT LEAST PARTIALLY CLEAR OUT AT
KIWD BY AFTN AS DOWNSLOPING EAST FLOW DEVELOPS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 304 PM EST MON DEC 8 2014
BEHIND THE LOW...N TO NW WINDS RAMP UP TONIGHT...AIDED BY PRES RISES
APPROACHING FROM THE NW. MAGNITUDE OF PRES RISES SUGGESTS POTENTIAL
FOR A FEW HRS WHEN WINDS MAY GUST TO NEAR 35KT FROM NCNTRL TO SCNTRL
LAKE SUPERIOR. WINDS WILL DIMINISH FROM W TO E TUE AS HIGH PRES
RIDGE APPROACHES. WITH THE HIGH PRES RIDGE ARRIVING OVER THE UPPER
LAKES TUE NIGHT/WED...LIGHTER WINDS UNDER 20KT ARE EXPECTED... AND
THESE LIGHTER WINDS SHOULD LINGER ON THRU THU AND POSSIBLY FRI AS
WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1244 AM EST TUE DEC 9 2014
.UPDATE...
ISSUED AT 713 PM EST MON DEC 8 2014
LOW PRESSURE SLIDING OVER CNTRL UPR MICHIGAN AS OF 23Z. COLD AIR IN
WAKE OF THE LOW SLOW TO ARRIVE. DEEP MOISTURE TIED INTO THE LOW HAS
FADED QUICKLY AND LEFTOVER MOISTURE IS SHALLOW IN DEPTH AND TEMPS
WITHIN THE MOIST LAYER ARE ONLY AS COOL AS -4C TO -6C OVER WESTERN
LK SUPERIOR AND WESTERN CWA. VSBY AT IWD AND CMX HAS BEEN BLO 5SM
SINCE SUNSET. REPORTS FM SOCIAL MEDIA INDICATE DRIZZLE OCCURRING
OVER KEWEENAW AND LOWER ELEVATIONS OF ONTONAGON COUNTY. SOME SNOW
FLURRIES ARE FALLING OVER HIGHER TERRAIN IN ONTONAGON COUNTY. ADDED
PATCHY DZ/FZDZ TO GRIDS UNTIL AROUND 06Z FOR WEST/NORTHWEST AND INTO
NCNTRL. RAP/NAM/GFS SOUNDINGS INDICATE AFTER 06Z IT BECOMES COLD
ENOUGH FOR MIXED PRECIP TO CHANGE TO MAINLY SNOW.
ADDED FOG TO MUCH OF EAST HALF OF CWA THROUGH THE EVENING WITH
SOUTHERLY FLOW OVER LK MICHIGAN PUSHING DWPNTS IN LOW 30S OVER THE
WET SNOW PACK FM THE SNOW THAT OCCURRED EARLIER TODAY. ALREADY SEEING
VSBY BLO 2SM OVER MOST OF THE EAST PART OF THE CWA...INCLUDING VSBY
DOWN TO 1/4SM IN THE LAST HOUR AT MNM. ONCE WINDS IN BLYR SHIFT TO NW
LATER THIS EVENING...FOG SHOULD BEGIN TO LIFT AS MOISTENING FLOW OFF
LK MICHIGAN WILL BE DIMINISHED.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 304 PM EST MON DEC 8 2014
LATEST WATER VAPOR IMAGERY AND RUC ANALYSIS THE SHOW SHORTWAVE TROF
MOVING ACROSS THE UPPER GREAT LAKES THIS AFTERNOON. MODELS INDICATE
BEST ISENTROPIC ASCENT...MOISTURE TRANSPORT AND DEEP LAYER Q-VECT
CONVERGENCE HAS SHIFTED EAST WITH MAIN SNOW BAND AHEAD OF THE SFC-8H
TROF OVER CENTRAL UPPER MI. IT/S POSSIBLE THERE MAY BE SOME PATCHY
-FZDZ LATE THIS AFTERNOON BEHIND THE SNOW BAND WITH MID-LVL DRYING
AND LOW-LVL MOISTURE TOO SHALLOW TO REACH THE -10C ISOTHERM...BUT
NOT SURE IF THE FZDZ WILL BE SIGNIFICANT ENOUGH TO INCLUDE IN FCST
GRIDS THIS EVENING.
MODELS INDICATE THAT N TO NW WINDS WILL STRENGTHEN TONIGHT BEHIND
DEPARTING LOW PRES TONIGHT. COOLING LOW-LEVEL AIR MASS MAY SUPPORT
SOME LAKE ENHANCED SNOW FOR A BRIEF TIME THIS EVENING.
HOWEVER...SNOWFALL IS EXPECTED TO BE LIGHT FOR THE FOLLOWING
REASONS...850MB TEMPS (AROUND -6C) ARE MARGINAL FOR ENHANCEMENT
WHILE DEEPER MOISTURE IS AROUND...LOW-LEVEL FLOW IS NOT STRONGLY
CYCLONIC...AND DGZ IS ABOVE THE UPWARD MOTION AND THE DEEPER
MOISTURE. UPSLOPE/OROGRAPHIC MOTION MAY BE THE DRIVING COMPONENT
AIDING SNOWFALL...AND WHERE THAT IS MAXIMIZED...EXPECT GENERALLY 1-2
INCHES OF SNOW TONIGHT OVER HIGHER TERRAIN NEAR LAKE SUPERIOR.
INCREASED SUBSIDENCE AND LOWERING OF INVERSION HGTS AHEAD OF THE
BUILDING MID-LVL RDG UPSTREAM MAY ALSO CONTRIBUTE TO A BRIEF PD OF
UPSLOPE FZDZ LATE TONIGHT OVER THE NRN TIER COUNTIES IN NRLY FLOW
LATE TONIGHT...BUT NAM SNDGS SHOW THE SHALLOW MOIST LAYER COOLING TO
-10C BY SUNRISE WHICH SHOULD AGAIN SUPPORT MAINLY LIGHT
SNOW/FLURRIES. SINCE FZDZ THREAT IS UNCERTAIN AND LOOKS TO BE BRIEF
IF IT DOES OCCUR WL LEAVE IT OUT OF GRIDS FOR NOW. LOOK FOR MIN
TEMPS RANGING FROM THE LOWER 20S INTERIOR WEST TO UPPER 20S EAST
HALF.
1034 MB SFC RIDGE BUILDING IN FROM THE WEST SHOULD WEAKEN THE PRES
GRADIENT AND THUS ALLOW NRLY WINDS TO DIMINISH ACROSS THE AREA BY
AFTERNOON. CONTINUED LOWERING OF INVERSION BASES BLO 3KFT WILL
QUICKLY DIMINISH ANY REMAINING LIGHT UPSLOPE SHSN TO FLURRIES BY
LATE MORNING. LOOK FOR HIGHS RANGING FROM THE LOWER TO MID 20S WEST
TO LOWER 30S EAST HALF.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 422 PM EST MON DEC 8 2014
DRY WEATHER WILL BE THE RULE THROUGH SATURDAY MORNING...WITH HIGH
PRESSURE FROM THE SFC-500MB. BOTH THE GFS AND ECMWF BRING SOME
MOISTURE BACK TO THE AREA DURING THE DAY SATURDAY...AS THE SFC RIDGE
EXITS E TO THE LOWER GREAT LAKES AND THE AXIS OF THE 500MB RIDGE
MOVES ACROSS THE UPPER GREAT LAKES. LOOK FOR SLOWLY INCREASING W-SW
WINDS DURING THE DAY SATURDAY WITH 850MB TEMPS WARMING TO 9 TO 12C.
THIS WILL BE QUITE A CHANGE FROM THE CURRENT VALUES WHICH ARE
HOVERING AROUND -4C.
THE MAIN CONCERN FOR THIS PERIOD WILL COME IN SATURDAY THROUGH
MONDAY. AS MOISTURE INCREASES...LIGHT WAA WILL LIKELY OVERSPREAD THE
CWA. KEPT THE MENTION OF PATCHY FOG AS WELL FOR THIS WILL BE IN
ADVANCE OF THE ELONGATED SFC LOW OVER THE N AND CENTRAL PLAINS AT
00Z SUNDAY WITH THE HIGH DEW POINTS OVER THE MELTING SNOWPACK. THE
12Z RUNS OF THE ECMWF AND GFS BOTH HAVE THE LOW OVER MN AT 12Z
SUNDAY...THEN SHIFTING ACROSS UPPER MI/LAKE SUPERIOR/CENTRAL ONTARIO
SUNDAY NIGHT. WITH LOW TEMPERATURES FALLING INTO THE MID 20S TO LOW
30S...THE POTENTIAL EXISTS FOR FREEZING RAIN OR FREEZING DRIZZLE.
WILL CONTINUE TO FOCUS ON THIS PERIOD...AND ADJUST AS NEEDED AS THE
TIME NEARS.
LOOK FOR THE COLD AIR TO SURGE IN BEHIND THE EXITING LOW/COLD FRONT
SUNDAY NIGHT INTO MONDAY...WITH PRECIP TURNING ALL BACK TO SNOW BY
MONDAY EVENING AT THE LATEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1242 AM EST TUE DEC 9 2014
LOW-LEVEL MOISTURE IN THE WAKE OF LOW PRESSURE MOVING OVER EASTERN
UPR MICHIGAN IS COMBINING WITH UPSLOPE FLOW TO MAINTAIN LIFR/IFR
CIGS AT ALL THE TAF SITES. EXPECT MVFR OR IFR VSBY OVERNIGHT WITH
SOME LGT SNOW SHOWERS OR EVEN DZ/FZDZ. IMPROVEMENT EXPECTED AT KCMX
LATE IN THE NIGHT AS UPSLOPING DIMINISHES. ADDITIONAL IMPROVEMENT WILL
OCCUR AT ALL THE TAF SITES TODAY BUT BKN-OVC MVFR CIGS SHOULD REMAIN
IN PLACE INTO THE EVENING AS MOISTURE REMAINS TRAPPED BENEATH
INVERSION. HOWEVER...SKIES SHOULD AT LEAST PARTIALLY CLEAR OUT AT
KIWD BY AFTN AS DOWNSLOPING EAST FLOW DEVELOPS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 304 PM EST MON DEC 8 2014
BEHIND THE LOW...N TO NW WINDS RAMP UP TONIGHT...AIDED BY PRES RISES
APPROACHING FROM THE NW. MAGNITUDE OF PRES RISES SUGGESTS POTENTIAL
FOR A FEW HRS WHEN WINDS MAY GUST TO NEAR 35KT FROM NCNTRL TO SCNTRL
LAKE SUPERIOR. WINDS WILL DIMINISH FROM W TO E TUE AS HIGH PRES
RIDGE APPROACHES. WITH THE HIGH PRES RIDGE ARRIVING OVER THE UPPER
LAKES TUE NIGHT/WED...LIGHTER WINDS UNDER 20KT ARE EXPECTED... AND
THESE LIGHTER WINDS SHOULD LINGER ON THRU THU AND POSSIBLY FRI AS
WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...VOSS
LONG TERM...KF
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1205 AM EST TUE DEC 9 2014
.AVIATION...
//DISCUSSION...
ABOUT A HALF INCH OF SNOW HAS BEEN REPORTED FROM THE MIDLAND AREA
DURING THE EVENING WHERE A MIX WITH RAIN ONLY OCCURRED BRIEFLY AT
THE ONSET. EXPECT ALL SNOW TO CONTINUE THERE WHILE A RAIN SNOW MIX
WILL BE MORE COMMON IN THE FNT AND PTK AREA...AND ALL RAIN AT DTW
UNTIL THE COLD FRONT MOVES THROUGH THE REGION. THE GREATEST
RESTRICTION WILL BE LIFR CEILING WITH MOSTLY IFR VISIBILITY IN FOG
AND DRIZZLE PRIOR TO THE GRADUAL WIND SHIFT TOWARD THE NORTHWEST.
COOLER AND DRIER AIR WILL THEN LEAD TO GRADUAL IMPROVEMENT TO MVFR
WHERE CONDITIONS WILL SETTLE THROUGH THE AFTERNOON INTO TUESDAY
EVENING.
FOR DTW... RAIN DURING THE EARLY MORNING COULD CONTAIN A FEW WET
SNOW FLAKES...BUT NOT ENOUGH FOR INCLUSION IN THE FORECAST AND WITH
NO ACCUMULATION.
//DTW THRESHOLD THREATS...
* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET DURING THE NIGHT
THROUGH AFTERNOON.
* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE.
* LOW CONFIDENCE IN VISIBILITY DROPPING BELOW 1/2 SM AND/OR CIGS
BELOW 200 FT.
&&
.PREV DISCUSSION...ISSUED 835 PM EST MON DEC 8 2014
UPDATE...
THE EARLIER UPDATE NUDGED THE FORECAST TOWARD A SLIGHTLY COLDER
PRECIPITATION TYPE SOLUTION BY ADDING A GREATER COMPONENT OF SNOW
OR A RAIN/SNOW MIX. THIS IS BASED ON RADAR INDICATIONS OF HIGHER
PRECIPITATION RATES CAPABLE OF GREATER WET BULB COOLING...BUT THE
OVERALL THERMAL PROFILE STILL SUPPORTS MOSTLY SNOW IN THE TRI
CITIES REGION WITH JUST A BRIEF RAIN/SNOW MIX IN THE DETROIT AREA
TO THE OHIO BORDER. PRECIPITATION RATES ARE BEING ENHANCED BY A
FAVORABLE COMBINATION OF DYNAMIC FORCING FROM THE UPPER WAVE
ACTING ON THE LOW TO MID LEVEL THETA-E RIDGE WHICH IS MATURING
INTO A WELL DEFINED TROWAL. STRONG VERTICAL MOTION RESPONSE...AND
THE POTENTIAL FOR IT TO CONTINUE...IS INDICATED BY STEEP MID LEVEL
LAPSE RATES CENTERED AROUND 700 MB IN THE NEW 00Z DTX SOUNDING AS
THE MOISTURE AXIS SLIDES THROUGH SE MICHIGAN DURING THE REST OF
THE EVENING.
THE MID LEVEL DRY SLOT ASSOCIATED WITH THE UPPER WAVE WILL BRING A
QUICK END TO THE SNOW BY MIDNIGHT. THE PROGRESSION OF THE PATTERN
WILL BE FAST ENOUGH TO HOLD THE LINE ON MINIMAL SNOW ACCUMULATION
OVER THE AREA. THE TRI CITIES AND NORTHERN THUMB REGION DOES HAVE
POTENTIAL FOR SNOW TO LINGER...AND MINOR UPWARD ADJUSTMENTS ON
ACCUMULATION...AS MOISTURE REMAINS DEEPER WITHIN THE DEFORMATION
AXIS ON THE NW FLANK OF THE WAVE AS IT TRACKS THROUGH THE SOUTHERN
GREAT LAKES. THE TRANSITION FROM SNOW TO DRIZZLE...OR LACK
THEREOF...WILL BE MONITORED DURING THE LATE EVENING. DRIZZLE AND
FOG WILL MOVE OVER THE REST OF SE MICHIGAN AND PERSIST UNTIL
NORTHWEST WIND INCREASES BEHIND THE COLD FRONT TOWARD SUNRISE.
PREV DISCUSSION...ISSUED 353 PM EST MON DEC 8 2014
SHORT TERM...THROUGH TONIGHT
19Z WATER VAPOR IMAGERY SHOWS WELL-DEFINED COMPACT MIDLEVEL WAVE
OVER THE MN/IA BORDER SPINNING SEWD. UPPER LEVEL MOISTURE WAS
PRESENT DOWNSTREAM OF THIS FEATURE OVER IN AND MI. MIDLEVEL
FRONTOGENESIS WAS SUPPORTING A NORTH/SOUTH ORIENTED SWATH OF LIGHT
TO MODERATE PRECIP OVER WESTERN MI AND NORTHERN IN...MOVING NEWD.
THERE WAS A SHARP LOW-LEVEL MOISTURE GRADIENT IN PLACE AS EVIDENCED
BY QUICKLY LOWERING CEILINGS AT THE ONSET OF PRECIPITATION. NWP IS
IN GOOD AGREEMENT OF THE AREA OF FGEN AND ASSOCIATED PRECIP SHIELD
TRANSLATING THROUGH THE LOCAL AREA BETWEEN AROUND 23-05Z /PERHAPS
WEAKENING SOMEWHAT/ WITH ANY ONE AREA SEEING AROUND 3-4 HOURS OF
PRECIP. QPF SHOULD BE GENERALLY LIGHT...AROUND .10-.15 INCHES.
PRECIP TYPE IS A BIT OF A CHALLENGE. TEMPERATURES THIS AFTERNOON
ARE IN THE UPPER 30S AND LOW 40S WITH DEWPOINTS STILL IN THE LOW/MID
20S OVER SE MI. RAP HAS A PRETTY GOOD HANDLE ON THIS WITH ASSOCIATED
WETBULB TEMPS 32-35F. NOT EXPECTING TEMPS TO DROP A WHOLE LOT IN
ADVANCE OF THE PRECIP WITH CLOUD COVER AND SOUTHERLY FLOW. DEWPOINTS
SHOULD EDGE UPWARD INTO THE UPPER 20S. WETBULB EFFECTS ONCE THE
PRECIP STARTS SHOULD DROP TEMPS INTO THE 33-37 DEGREE RANGE. WHILE
MUCH OF THE REGION COULD EXPERIENCE A MIX OF RAIN AND SNOW /WITH
SNOW MORE LIKELY IN THE AREAS OF EMBEDDED HEAVIER PRECIP/...HAVE
GONE WITH PREDOMINANTLY RAIN FOR METRO DETROIT AND SOUTH...MOSTLY
SNOW FOR THE SAGINAW VALLEY AND NORTHERN THUMB...AND A MIX
INBETWEEN. EXPECTING LOWS IN THE AREAS THAT EXPERIENCE SNOW TO
MAINLY REMAIN AOA FREEZING WITH LOW SNOW RATIOS SO ACCUMULATIONS ARE
NOT MUCH OF A CONCERN...WITH PERHAPS UP TO HALF AN INCH IN SPOTS
ALONG AND NORTH OF I-69.
ONCE THE UPPER MOISTURE STRIPS AWAY AFTER MIDNIGHT...THE SURFACE LOW
WILL TRANSLATE OVER THE REGION CAUSING WINDS TO BECOME LIGHT. LOW-
LEVEL MOISTURE WILL STILL BE AROUND. UPSTREAM OBS INDICATE
WIDESPREAD LOW CLOUDS WITH AREAS OF FOG AND DRIZZLE AND EXPECT THAT
WILL BE THE CASE OVER OUR AREA AS WELL. PATCHY AREAS OF FREEZING
DRIZZLE ARE POSSIBLE WHERE TEMPS GET CLOSER TO FREEZING...ESPECIALLY
OVER THE NORTHERN PARTS OF THE FORECAST AREA.
LONG TERM...TUESDAY THROUGH SUNDAY
THE EXTENDED FORECAST WILL START OFF WITH AN UPPER LEVEL TROUGH OVER
THE GREAT LAKES DRIFTING OFF TO THE MID ATLANTIC COAST AS IT BECOMES
A CLOSED MID LEVEL CIRCULATION. SE MI WILL BE UNDER THE UPPER LEVEL
COLD POOL AND BROAD LIFT FROM THE TROUGH DURING THE MID WEEK PERIOD
BEFORE LONGWAVE RIDGE BUILDING UP THROUGH THE CENTRAL CONUS TRIES TO
FORCE ITS WAY INTO THE REGION. A BLOCKING PATTERN LOOKS TO SET UP BY
THE END OF THE WEEK WITH THE INTERFACE BETWEEN THE RIDGE AND TROUGH
IN THE VICINITY OF EASTERN MI. THIS PRESENTS ONE OF THE MAIN
CHALLENGES IN THE LONG TERM AS THAT IS THE DIFFERENCE BETWEEN A MILD
SUNNY WEEKEND OR A CLOUDY WEEKEND WITH THE POSSIBILITY OF LIGHT
SNOWFALL.
WE START OFF TUESDAY WITH THE TROUGH AXIS OVER HEAD WHICH WILL
PRODUCE OVERCAST SKIES AND WINDS VEERING FROM SOUTHERLY TO NORTHERLY
THROUGH THE AFTERNOON. ADDITIONALLY...THE BROAD CYCLONIC FLOW AND
LIFT WITH A SATURATED COLUMN UP TO 8KFT WILL PRODUCE SOME LINGERING
SHOWERS THROUGH THE DAY AS THE FORCING PULLS OFF TO THE EAST. ONE
QUESTION REMAINS TO BE WHAT WILL THE PTYPE BE ON TUESDAY? THE TREND
WILL BE FOR THE COLUMN TO COOL AS THE -26C 500MB COLD POOL SLIDE
OVER THE AREA. 925MB TEMPS WILL BE CLOSE TO ZERO WITH 850MB TEMPS A
COUPLE DEGREES IN THE NEGATIVE. BUT THE SATURATION ONLY CLIMBS TO
AROUND 750MB OR SO WHICH MAY NOT QUITE BE ENOUGH FOR ALL ICE
CRYSTALS WITH TEMPS NEARING -9C. SO KEPT THE MENTION OF DRIZZLE
THROUGH THE FIRST HALF OF THE DAY POSSIBLY SWITCHING OVER TO ALL
SNOW CLOSER TO 00Z WEDNESDAY. TEMPERATURES ABOVE FREEZING UP TOWARD
950MB...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE CWA SHOULD
PREVENT FREEZING DRIZZLE AS SFC TEMPS REACH INTO THE UPPER 30S.
THE NATURE OF THE PRECIP FORCING CHANGES OVERNIGHT TUESDAY INTO
WEDNESDAY AS THE DEEPER MOISTURE GETS PULLED EAST LEAVING A VERY
SHALLOW LAYER OF MOISTURE WITH NORTHERLY FLOW. THIS COLDER NORTHERLY
FLOW OFF LAKE HURON WILL LIKELY PRODUCE SOME LAKE EFFECT SNOW OVER
THE THUMB BUT MODELS DO NO INDICATE ANY STRONG CONVERGENT REGIONS
OVER THE LAKE AND DELTA T FROM THE SFC TO 850MB IS RATHER WEAK
AROUND 10C. WILL CONTINUE THE HIGHER POP...LOWER QPF FORECAST FOR
THE THUMB UNTIL WE SEE MORE DEFINITIVE SIGNATURES TO LOWER THE POPS
OR START THINKING IN TERMS OF POSSIBLE ACCUMULATIONS. TEMPERATURES
OVER LAND WEDNESDAY WILL HOLD AROUND THE FREEZING MARK AS THE
BACKSIDE OF THE COLD POOL ALOFT LINGERS OVER THE EASTERN GREAT
LAKES.
HIGH PRESSURE...AND DRY WEATHER...LOOKS TO REMAIN IN PLACE THROUGH
MUCH OF THE EXTENDED PERIOD. SOME RECENT MODEL RUNS INDICATE A
CHANCE OF SOME SNOW SHOWERS TRYING TO CREEP IN ON THURSDAY AS A LOW
PRESSURE SYSTEM DEVELOPS TO OUR EAST. CONFIDENCE IN THIS FEATURE AT
THIS TIME IS LOW AND HAVE ONLY INCLUDED A SLIGHT CHANCE OF SOME SNOW
FOR THE EXTREME EASTERN PORTION OF THE CWA /ST CLAIR SANILAC AND
EASTERN HURON COUNTIES/. OTHERWISE DRY CONDITIONS PREVAIL THROUGH
THE WEEKEND WITH THE NEXT DISTURBANCE ARRIVING LATE SUNDAY. CURRENT
MODEL GUIDANCE SHOWS TEMPERATURES WILL BE WARM ENOUGH FOR
PRECIPITATION WITH THIS SYSTEM TO BE ALL RAIN...HOWEVER...WOULD NOT
BE SURPRISED IF SOME SNOW MIXES IN ON SUNDAY NIGHT AS TEMPERATURES
BEGIN TO DROP. FOR NOW HAVE JUST LEFT THE PRECIPITATION AS ALL RAIN
BUT SNOW MAY HAVE TO BE ADDED LATER AS WE GET A BETTER SAMPLING OF
HOW THIS SYSTEM WILL PLAY OUT.
MARINE...
AN UPPER LEVEL TROUGH OF LOW PRESSURE AND ASSOCIATED WEAK SURFACE
REFLECTION WILL BRING UNSETTLED WEATHER TO THE GREAT LAKES FOR THE
NEXT COUPLE DAYS. SOUTHERLY FLOW AHEAD OF THE TROUGH IS BEGINNING TO
SETTLE ALLOWING US TO CANCEL THE SMALL CRAFT ADVISORY OVER SAGINAW
BAY A FEW HOURS EARLY BUT FLOW OVER LAKE HURON WILL WARRANT THE
CONTINUATION OF THE NEARSHORE SMALL CRAFTS THROUGH THE EVENING WITH
GUSTS AROUND 25 KNOTS AND ELEVATED WAVE HEIGHTS. THE TROUGH AXIS
WILL TRACK ACROSS THE AREA TUESDAY VEERING WINDS AROUND TO THE
NORTH. COLD AIR ADVECTION BEHIND A PASSING COLD FRONT OVER THE
SLIGHTLY WARMER WATERS...WITH A TIGHTENING PRESSURE GRADIENT BETWEEN
THE STALLING UPPER LEVEL TROUGH AND THE RIDGE TRYING TO BUILD IN
FROM THE WEST WILL HELP EXCITE THE WIND FIELD ONCE AGAIN. A MARGINAL
GALE WATCH CONTINUES FOR THE SOUTHERN LAKE HURON BASIN AS WINDS LOOK
TO GUST NEAR 35 KNOTS WITH THIS SETUP. THE UPPER LEVEL FEATURE MAY
TRY TO HEAD BACK WEST TOWARD THE AREA LATER IN THE WEEK WHICH WOULD
KEEP SOME SEMBLANCE OF THE INCREASED NORTHERLY FLOW THROUGH MID
WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM THIS EVENING THROUGH WEDNESDAY MORNING FOR
LHZ441>443-462>464.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....BT
UPDATE.......BT
SHORT TERM...DT
LONG TERM....DRK/RK
MARINE.......DRK
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1040 AM CST TUE DEC 9 2014
.UPDATE...EXPECT SUNNY SKIES ACROSS MUCH OF THE ARKLAMISS TODAY.
SOME CLOUDS MAY MOVE INTO NORTHERN ZONES THIS AFTERNOON AS A DRY
COLD FRONT MOVES THROUGH. HIGH TEMPS TEMPS THIS AFTERNOON LOOK TO
RANGE FROM THE MID 50S NORTH TO THE MID 60S SOUTH. THE CURRENT
FORECAST IS IN GOOD SHAPE...WITH ONLY MINOR ADJUSTMENTS TO THE
HOURLY TEMPS FOR LATE THIS MORNING. /27/
&&
.AVIATION...MORNING FOG IS SLOWLY CLEARING AND MOST SITS HAVE
RESUMED VFR CONDITIONS. KGLH/KGWO ARE SLOWER TO CLEAR AND THESE
WILL HANG ONTO MVFR CONDITIONS TIL ALMOST 17-18Z. VFR CONDITIONS
WILL PREVAIL TODAY. A COLD FRONT WILL MOVE THROUGH TODAY AND MAY
BRING SOME MVFR RESTRICTIONS IN THE NORTH AFTER 20Z. THIS WILL
REINFORCE NORTHERLY WINDS AROUND 5-10KTS. /28/
&&
.PREV DISCUSSION... /ISSUED 402 AM CST TUE DEC 9 2014/
SHORT TERM...FOCUS OF THIS SHORT TERM CONTINUES TO BE WITH THE
REINFORCING SHOT OF COOLER AIR FOR LATER TODAY. FROM THIS...THE MAIN
FORECAST ELEMENTS WILL BE ON TEMPS AND CLOUDS.
THE NOTICEABLE ARRIVAL OF THE COOLER AIR WILL NOT BE UNTIL LATER IN
THE AFTERNOON AND EVENING FOR THE CWA. PRIOR TO THAT...SFC WINDS
WILL BE OUT OF THE NW...BUT FULL SUNSHINE AND SOMEWHAT OF A FLAT LOW
LEVEL THERMAL AXIS WILL ALLOW FOR A BETTER WARMUP THAN PREV
EXPECTED. DUE TO THIS...AREAS SOUTH OF THE HWY 82 CORRIDOR SHOULD
PEAK BETWEEN 60-66 DEGREES AND I HAVE USED VALUES THAT WERE ON THE
UPPER END OF THE GUID ENVELOP. FOR LOCATIONS ALONG AND NORTH OF HWY
82...THIS IS MORE TRICKY AS THE PROGRESSION OF THE COOLER AIR LOOKS
TO ARRIVE HERE IN TIME TO LIMIT WARMING A BIT. A BLEND OF THE HI-RES
AND RAP MODELS WERE USED HERE AND HIGHS MAY ONLY REACH 53-58. AS FOR
CLOUDS...PREV EXPECTATIONS WERE FOR CLEAR SKIES. HOWEVER...THE
LATEST NAM/RAP INDICATE THAT FRONTAL LIFT ALONG WITH STRONG CAA WILL
SUPPORT AT LEAST A BKN DECK NEAR AND BEHIND THE FRONT.
FOR TONIGHT...THESE LOW CLOUDS SHOULD DISSIPATE DURING THE
OVER...BUT THEN BEGIN TO GET REPLACED BY INCREASING/THICKENING HIGH
CLOUDS...ESPECIALLY FOR MIDDAY WED AND INTO THE AFTERNOON/EVE. LOWS
TONIGHT ARE NOT CLEAR CUT AS THE GFS MOS IS COOLER AND OTHER GUID IS
A BIT WARMER. I LIKE A BLEND WITH A LEAN TOWARD THE WARMER GUID DUE
TO SFC WINDS STAYING UP OVERNIGHT. SOME FREEZING TEMPS ARE POSSIBLE
ACROSS THE N HALF...BUT IF THAT OCCURS IT WILL BE BRIEF. HIGHS WED
WILL BE ON THE COOL SIDE AND RANGE FROM THE UPPER 40S N TO MID 50S
S. A COMBO OF CAA AND HIGH CLOUDS WILL KEEP TEMPS IN CHECK. IF THE
HIGH CLOUDS BECOME THICK ENOUGH...READINGS COULD FALL SHORT OF
EXPECTED VALUES.
WED NIGHT WILL BE THE COLDEST NIGHT THIS WEEK...BUT I WILL NOT GET
TOO AGGRESSIVE AND MUCH OF THE COOLING WILL DEPEND ON IF THE HIGH
CLOUDS EXIT OR THIN ENOUGH. ALL THE AVAILABLE GUID IS CLOSE WITH
UPPER 20S N TO LOWER 30S S AS THE RANGE. THU WILL BE A TAD WARMER AS
SOME MODIFICATION OCCURS THANKS TO A BIT MORE SUN WITH A MIX OF
CLOUDS AS WELL. /CME/
LONG TERM...THURSDAY NIGHT THROUGH NEXT MONDAY...
GLOBAL MODELS ARE REMARKABLY CONSISTENT CONSIDERING THE AMPLIFIED
PATTERN THAT IS FORECAST TO EVOLVE. A DEEP TROUGH ALONG THE EAST
COAST AT THE START OF THE PERIOD WILL SHIFT EAST AND ALLOW A RIDGE
TO MOVE ACROSS THE MS VALLEY THROUGH THE WEEKEND. FRIDAY WILL BE
SEASONABLY COOL...BUT THEN EXPECT TEMPERATURES TO WARM SOME SATURDAY
AND SUNDAY TO SLIGHTLY ABOVE CLIMATIC NORMALS AS SURFACE PRESSURES
FALL AND RETURN FLOW BEGINS TO DEVELOP.
EMPHASIS WILL THEN SHIFT TO THE SOUTHERN STREAM AND A SIGNIFICANT
SHORTWAVE TROUGH EXPECTED TO MOVE INTO THE LOWER MS VALLEY REGION
EARLY NEXT WEEK. MODEL DIFFERENCES START TO DEVELOP WITH HANDLING OF
THIS TROUGH AND HOW MUCH PHASING TAKES PLACE - THE ECWMF IS MORE
DISTINCT/SEPARATE AND THEREFORE A LITTLE SLOWER AND MORE ROBUST WITH
CONVECTIVE PRECIPITATION IN THE ARKLAMISS WHILE THE GFS/GEFS
INDICATE MORE ENERGY IN THE NORTHERN STREAM. THE AMPLIFIED PATTERN
MAY SUPPORT MORE OF A CLOSED OFF SOLUTION SUCH PER THE ECWMF...BUT
INSTABILITY WILL BE VERY LIMITED AS THE PRECEDING HIGH DOES NOT
ALLOW FOR MUCH OF A WINDOW FOR SIGNIFICANT WARM ADVECTION/MOISTURE
TRANSPORT. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 63 33 51 33 / 0 0 0 0
MERIDIAN 63 32 51 30 / 0 0 0 0
VICKSBURG 64 33 51 32 / 0 0 0 0
HATTIESBURG 66 35 55 33 / 0 0 0 0
NATCHEZ 64 35 52 34 / 0 0 0 0
GREENVILLE 56 32 48 31 / 0 0 0 0
GREENWOOD 56 31 49 30 / 0 0 0 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON MS
402 AM CST TUE DEC 9 2014
.SHORT TERM...FOCUS OF THIS SHORT TERM CONTINUES TO BE WITH THE
REINFORCING SHOT OF COOLER AIR FOR LATER TODAY. FROM THIS...THE MAIN
FORECAST ELEMENTS WILL BE ON TEMPS AND CLOUDS.
THE NOTICEABLE ARRIVAL OF THE COOLER AIR WILL NOT BE UNTIL LATER IN
THE AFTERNOON AND EVENING FOR THE CWA. PRIOR TO THAT...SFC WINDS
WILL BE OUT OF THE NW...BUT FULL SUNSHINE AND SOMEWHAT OF A FLAT LOW
LEVEL THERMAL AXIS WILL ALLOW FOR A BETTER WARMUP THAN PREV
EXPECTED. DUE TO THIS...AREAS SOUTH OF THE HWY 82 CORRIDOR SHOULD
PEAK BETWEEN 60-66 DEGREES AND I HAVE USED VALUES THAT WERE ON THE
UPPER END OF THE GUID ENVELOP. FOR LOCATIONS ALONG AND NORTH OF HWY
82...THIS IS MORE TRICKY AS THE PROGRESSION OF THE COOLER AIR LOOKS
TO ARRIVE HERE IN TIME TO LIMIT WARMING A BIT. A BLEND OF THE HI-RES
AND RAP MODELS WERE USED HERE AND HIGHS MAY ONLY REACH 53-58. AS FOR
CLOUDS...PREV EXPECTATIONS WERE FOR CLEAR SKIES. HOWEVER...THE
LATEST NAM/RAP INDICATE THAT FRONTAL LIFT ALONG WITH STRONG CAA WILL
SUPPORT AT LEAST A BKN DECK NEAR AND BEHIND THE FRONT.
FOR TONIGHT...THESE LOW CLOUDS SHOULD DISSIPATE DURING THE
OVER...BUT THEN BEGIN TO GET REPLACED BY INCREASING/THICKENING HIGH
CLOUDS...ESPECIALLY FOR MIDDAY WED AND INTO THE AFTERNOON/EVE. LOWS
TONIGHT ARE NOT CLEAR CUT AS THE GFS MOS IS COOLER AND OTHER GUID IS
A BIT WARMER. I LIKE A BLEND WITH A LEAN TOWARD THE WARMER GUID DUE
TO SFC WINDS STAYING UP OVERNIGHT. SOME FREEZING TEMPS ARE POSSIBLE
ACROSS THE N HALF...BUT IF THAT OCCURS IT WILL BE BRIEF. HIGHS WED
WILL BE ON THE COOL SIDE AND RANGE FROM THE UPPER 40S N TO MID 50S
S. A COMBO OF CAA AND HIGH CLOUDS WILL KEEP TEMPS IN CHECK. IF THE
HIGH CLOUDS BECOME THICK ENOUGH...READINGS COULD FALL SHORT OF
EXPECTED VALUES.
WED NIGHT WILL BE THE COLDEST NIGHT THIS WEEK...BUT I WILL NOT GET
TOO AGGRESSIVE AND MUCH OF THE COOLING WILL DEPEND ON IF THE HIGH
CLOUDS EXIT OR THIN ENOUGH. ALL THE AVAILABLE GUID IS CLOSE WITH
UPPER 20S N TO LOWER 30S S AS THE RANGE. THU WILL BE A TAD WARMER AS
SOME MODIFICATION OCCURS THANKS TO A BIT MORE SUN WITH A MIX OF
CLOUDS AS WELL. /CME/
.LONG TERM...THURSDAY NIGHT THROUGH NEXT MONDAY...
GLOBAL MODELS ARE REMARKABLY CONSISTENT CONSIDERING THE AMPLIFIED
PATTERN THAT IS FORECAST TO EVOLVE. A DEEP TROUGH ALONG THE EAST
COAST AT THE START OF THE PERIOD WILL SHIFT EAST AND ALLOW A RIDGE
TO MOVE ACROSS THE MS VALLEY THROUGH THE WEEKEND. FRIDAY WILL BE
SEASONABLY COOL...BUT THEN EXPECT TEMPERATURES TO WARM SOME SATURDAY
AND SUNDAY TO SLIGHTLY ABOVE CLIMATIC NORMALS AS SURFACE PRESSURES
FALL AND RETURN FLOW BEGINS TO DEVELOP.
EMPHASIS WILL THEN SHIFT TO THE SOUTHERN STREAM AND A SIGNIFICANT
SHORTWAVE TROUGH EXPECTED TO MOVE INTO THE LOWER MS VALLEY REGION
EARLY NEXT WEEK. MODEL DIFFERENCES START TO DEVELOP WITH HANDLING OF
THIS TROUGH AND HOW MUCH PHASING TAKES PLACE - THE ECWMF IS MORE
DISTINCT/SEPARATE AND THEREFORE A LITTLE SLOWER AND MORE ROBUST WITH
CONVECTIVE PRECIPITATION IN THE ARKLAMISS WHILE THE GFS/GEFS
INDICATE MORE ENERGY IN THE NORTHERN STREAM. THE AMPLIFIED PATTERN
MAY SUPPORT MORE OF A CLOSED OFF SOLUTION SUCH PER THE ECWMF...BUT
INSTABILITY WILL BE VERY LIMITED AS THE PRECEDING HIGH DOES NOT
ALLOW FOR MUCH OF A WINDOW FOR SIGNIFICANT WARM ADVECTION/MOISTURE
TRANSPORT. /EC/
&&
.AVIATION...TRICKY VIS FORECAST THIS MORNING AS PATCHY SHALLOW
GROUND FOG IS CAUSING SITES TO BOUNCE WITH IFR/MVFR/VFR VIS
CONDITIONS. THIS SHOULD IMPROVE BETWEEN 13-15Z WITH VFR CONDITIONS
EXPECTED ACROSS MUCH OF THE AREA FOR MUCH OF THE DAY. THE EXCEPTION
WILL BE ACROSS THE N HALF WHERE A MVFR CIG LOOKS TO OCCUR WITH THE
PASSAGE OF THE FRONT AFTER 20Z AND LINGER TO ABOUT 01-03Z. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 63 33 51 33 / 0 0 0 0
MERIDIAN 63 32 51 30 / 0 0 0 0
VICKSBURG 64 33 51 32 / 0 0 0 0
HATTIESBURG 66 35 55 33 / 0 0 0 0
NATCHEZ 64 35 52 34 / 0 0 0 0
GREENVILLE 56 32 48 31 / 0 0 0 0
GREENWOOD 56 31 49 30 / 0 0 0 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
CME/EC/
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1112 AM CST Tue Dec 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 315 AM CST Tue Dec 9 2014
Vort max which dropped across the region overnight is now working
its way into the TN valley, with associated cold front currently
dropping into far s counties of our CWA. Early morning 11-3.9 low
cloud imagery indicates an extensive area of ST and SC in the wake
of the front, with this low cloud deck extending into the upper
Mississippi Valley and upper Great Lakes with only a few minor
breaks noted.
While can`t rule out a bit of sunshine, believe clouds will dominate
much of the region today due to the extensive low level moisture
trapped beneath a fairly stout inversion, as suggested by 925mb RH
progs from both the RUC and NAM. Today will certainly be cooler
than yesterday, and I`ve attempted to try to limit diurnal swing
as clouds should definitely inhibit a big daytime temp swing.
However, if a solid cloud deck holds throughout the day going max
temps may still be a bit too warm.
Truett
.LONG TERM: (Tonight through Monday)
Issued at 315 AM CST Tue Dec 9 2014
(Tonight-Thursday)
Chilly and tranquil weather should continue during this time
frame, and the primary forecast concern is how short-term low
cloud trends will evolve heading into midweek. Given forecast
inversion and north-northeast low level flow forecast across the
area as surface ridge works into the upper Mississippi Valley,
believe low clouds will hold over the region tonight and will
likely have a tendency to hang tough through Wednesday, with some
additional mid level cloudiness spilling into the area as strong
but moisture-starved shortwave zips down the back side of the
large upper level low winding up over the east coast.
Temperatures should moderate a bit by Thursday with a slightly
warmer airmass and a bit more sunshine.
(Friday-Monday)
Medium range solutions take eastern U.S. low up the eastern
seaboard heading into the end of the week, allowing upper level
ridge to work into the central CONUS. Resultant warming of the
AMS over the mid-Mississippi Valley should provide a strong
rebound in temps across the FA, with highs in the 50s by the end
of the week.
UA pattern over the CONUS becomes even more progressive by late in
the period, allowing aforementioned ridge to push east and deep UA
trof over the western U.S. to sweep into the Plains. This could
mean some precip in our CWA by Sunday, with better chances by the
start of the new work week. This system should be a rain-maker for
our area due to the relatively mild AMS.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1053 AM CST Tue Dec 9 2014
Although there may be a few thin spots or holes in the shallow
low level stratus cloud deck, it appears that the low level cloud
ceiling will continue through the forecast period. The cloud
ceiling will rise to around 3000 feet at some of the taf sites
this afternoon, but then likely drop down to 1000-1500 feet late
tonight with patchy light fog possible as the n-nwly surface wind
becomes light nely tonight.
Specifics for KSTL: Cloud ceiling height should hover around
2500-3000 feet this afternoon, then likely drop to around
1000-1500 feet late tonight/early Wednesday morning. The ceiling
will graduallly rise to near 3000 feet again Wednesday afternoon.
N-nwly surface wind will veer around to a nely direction and
become light this evening as the surface ridge extending from MN
southwest into central KS shfits slowly eastward.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
518 AM CST Tue Dec 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 315 AM CST Tue Dec 9 2014
Vort max which dropped across the region overnight is now working
its way into the TN valley, with associated cold front currently
dropping into far s counties of our CWA. Early morning 11-3.9 low
cloud imagery indicates an extensive area of ST and SC in the wake
of the front, with this low cloud deck extending into the upper
Mississippi Valley and upper Great Lakes with only a few minor
breaks noted.
While can`t rule out a bit of sunshine, believe clouds will dominate
much of the region today due to the extensive low level moisture
trapped beneath a fairly stout inversion, as suggested by 925mb RH
progs from both the RUC and NAM. Today will certainly be cooler
than yesterday, and I`ve attempted to try to limit diurnal swing
as clouds should definitely inhibit a big daytime temp swing.
However, if a solid cloud deck holds throughout the day going max
temps may still be a bit too warm.
Truett
.LONG TERM: (Tonight through Monday)
Issued at 315 AM CST Tue Dec 9 2014
(Tonight-Thursday)
Chilly and tranquil weather should continue during this time
frame, and the primary forecast concern is how short-term low
cloud trends will evolve heading into midweek. Given forecast
inversion and north-northeast low level flow forecast across the
area as surface ridge works into the upper Mississippi Valley,
believe low clouds will hold over the region tonight and will
likely have a tendency to hang tough through Wednesday, with some
additional mid level cloudiness spilling into the area as strong
but moisture-starved shortwave zips down the back side of the
large upper level low winding up over the east coast.
Temperatures should moderate a bit by Thursday with a slightly
warmer airmass and a bit more sunshine.
(Friday-Monday)
Medium range solutions take eastern U.S. low up the eastern
seaboard heading into the end of the week, allowing upper level
ridge to work into the central CONUS. Resultant warming of the
AMS over the mid-Mississippi Valley should provide a strong
rebound in temps across the FA, with highs in the 50s by the end
of the week.
UA pattern over the CONUS becomes even more progressive by late in
the period, allowing aforementioned ridge to push east and deep UA
trof over the western U.S. to sweep into the Plains. This could
mean some precip in our CWA by Sunday, with better chances by the
start of the new work week. This system should be a rain-maker for
our area due to the relatively mild AMS.
Truett
&&
.AVIATION: (For the 12z TAFs through 12z Wednesday Morning)
Issued at 515 AM CST Tue Dec 9 2014
MVFR stratus has returned to the region in the wake of the cold
front and is expected to hang around through mid-week. Can`t rule
out ceiling dropping into IFR range, but not confident enought to
include in forecast at this time. North wind will become light as
surface high moves closer.
Specifics for KSTL:
MVFR stratus expected with north wind becoming light and variable
tonight.
CVKING
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
317 AM CST Tue Dec 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 315 AM CST Tue Dec 9 2014
Vort max which dropped across the region overnight is now working
its way into the TN valley, with associated cold front currently
dropping into far s counties of our CWA. Early morning 11-3.9 low
cloud imagery indicates an extensive area of ST and SC in the wake
of the front, with this low cloud deck extending into the upper
Mississippi Valley and upper Great Lakes with only a few minor
breaks noted.
While can`t rule out a bit of sunshine, believe clouds will dominate
much of the region today due to the extensive low level moisture
trapped beneath a fairly stout inversion, as suggested by 925mb RH
progs from both the RUC and NAM. Today will certainly be cooler
than yesterday, and I`ve attempted to try to limit diurnal swing
as clouds should definitely inhibit a big daytime temp swing.
However, if a solid cloud deck holds throughout the day going max
temps may still be a bit too warm.
Truett
.LONG TERM: (Tonight through Monday)
Issued at 315 AM CST Tue Dec 9 2014
(Tonight-Thursday)
Chilly and tranquil weather should continue during this time
frame, and the primary forecast concern is how short-term low
cloud trends will evolve heading into midweek. Given forecast
inversion and north-northeast low level flow forecast across the
area as surface ridge works into the upper Mississippi Valley,
believe low clouds will hold over the region tonight and will
likely have a tendency to hang tough through Wednesday, with some
additional mid level cloudiness spilling into the area as strong
but moisture-starved shortwave zips down the back side of the
large upper level low winding up over the east coast.
Temperatures should moderate a bit by Thursday with a slightly
warmer airmass and a bit more sunshine.
(Friday-Monday)
Medium range solutions take eastern U.S. low up the eastern
seaboard heading into the end of the week, allowing upper level
ridge to work into the central CONUS. Resultant warming of the
AMS over the mid-Mississippi Valley should provide a strong
rebound in temps across the FA, with highs in the 50s by the end
of the week.
UA pattern over the CONUS becomes even more progressive by late in
the period, allowing aforementioned ridge to push east and deep UA
trof over the western U.S. to sweep into the Plains. This could
mean some precip in our CWA by Sunday, with better chances by the
start of the new work week. This system should be a rain-maker for
our area due to the relatively mild AMS.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Tuesday Night)
Issued at 1128 PM CST Mon Dec 8 2014
Secondary cold front is making its way south across forecast area
as of 05z. It should move south of I-70 by 06z Tuesday. Plenty of
stratus associated with frontal boundary as cigs have dropped to
MVFR at KUIN and should at rest of taf sites by 09z Tuesday.
Though KCOU will be on western edge of cloud deck. Otherwise, MVFR
cigs to persist through rest of taf forecast period with gusty
north winds diminishing a bit just after sunrise. Surface ridge to
build back in by Tuesday evening with winds becoming northeasterly.
Specifics for KSTL:
Secondary cold front is making its way south across forecast area
as of 05z. It should move south of I-70 by 06z Tuesday. Plenty of
stratus associated with frontal boundary with cigs dropping to
MVFR by 09z Tuesday. MVFR cigs to persist through rest of taf
forecast period with gusty north winds diminishing a bit by 15z Tuesday.
Surface ridge to build back in by Tuesday evening with winds
becoming northeasterly by 03z Wednesday.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
619 PM CST WED DEC 10 2014
.SYNOPSIS...
ISSUED AT 329 PM CST WED DEC 10 2014
A STORM WITH HURRICANE FORCE WINDS IS APPROACHING THE ALEUTIANS
AND CAUSING A LARGE PORTION OF THE ALEUTIAN UPPER LEVEL LOW TO
SPLIT FUELING A POWERFUL PACIFIC STORM AIMED AT THE WEST COAST
TONIGHT AND THURSDAY. THIS STORM WILL MOVE THROUGH THE ROCKIES
FRIDAY AND SATURDAY AND REDEVELOP INTO A STRONG WINTER STORM
ACROSS THE CNTL PLAINS SUNDAY AND MONDAY. CONDITIONS ARE FAVORABLE
FOR THE DEVELOPMENT OF A PLAINS STORM AND THE FORECAST
CONCERNS...INCREASING MOISTURE...CLOUDS AND TEMPERATURES AHEAD OF
THE STORM. THE MODELS ARE COMING INTO REASONABLY GOOD AGREEMENT
FOR A GOOD CHANCE OF RAIN CHANGING TO SNOW SUNDAY...WITH SNOW
POSSIBLE MONDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 329 PM CST WED DEC 10 2014
LOW LEVEL MOISTURE AND RESULTANT STRATUS REMAIN TRAPPED BENEATH AN
INVERSION ACROSS PORTIONS OF CENTRAL INTO EASTERN NEBRASKA.
SOUNDINGS INDICATE THIS INVERSION WILL REMAIN WITH MOISTURE
REMAINING TRAPPED IN THE BOUNDARY LAYER. EXPECT STRATUS TO REMAIN IN
PLACE AND EXPAND SLIGHTLY WEST TONIGHT...AND AS CEILINGS LOWER
EXPECT AREAS OF FOG TO REDEVELOP. SOME LOCALLY DENSE FOG IN
POSSIBLE...ESPECIALLY ON THE WESTERN FRINGE OF THE STRATUS DECK.
OVERALL THERE HAS BEEN A SLIGHT INCREASE IN MOISTURE OVER THE PAST
24 HRS...WITH DEW POINTS IN THE MID 20S TO LOWER 30S THIS AFTERNOON
AT ALL LOCATIONS. EXPECT FROST TO FORM ONCE AGAIN TONIGHT AS THE
TEMPERATURE DROPS BELOW FREEZING.
INVERSION REMAINS IN PLACE ACROSS CENTRAL INTO EASTERN NEBRASKA
THURSDAY. STRATUS WILL BE SLOW TO ERODE ONCE AGAIN. IN FACT...WITH
THE SOUTHERLY LOW LEVEL FLOW CONTINUING TO SLOWLY ADVECT LOW LEVEL
MOISTURE NORTHWARD INTO THE AREA...IT MAY NOT DISSIPATE AT ALL. HAVE
LOWERED HIGHS A FEW DEGREES FOR AREAS AROUND ONEILL TO BROKEN BOW
AND EAST TO ACCOUNT FOR THIS POSSIBILITY. FARTHER WEST...MIXING
POTENTIAL IS MUCH BETTER...AND INHERITED HIGH TEMPERATURES IN THE
50S LOOK GOOD.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 329 PM CST WED DEC 10 2014
THURSDAY NIGHT THROUGH SATURDAY...THE MODELS INDICATE MOISTURE WILL
CONTINUE TO INCREASE TONIGHT THROUGH SATURDAY. THE MODELS SHOW QUITE
AN EXPANSIVE AREA OF STRATUS LASTING THROUGHOUT THE DAY SATURDAY.
THIS IS LIKELY THE RESULT OF THE APPROACHING STORM AND THE BACKED
FLOW ALOFT DRAWING MOISTURE FURTHER WEST THAN THE EARLIER MODEL
RUNS. THE MODELS ARE ALL ON BOARD WITH DRIZZLE SATURDAY MORNING AND
THE ECM SHOWS DRIZZLE FRIDAY MORNING...MAINLY ALONG AND EAST OF
HIGHWAY 83.
THE TEMPERATURE FORECAST IS COMING UNDER SCRUTINY GIVEN THE
INCREASING MOISTURE. CLOUD COVER WILL HAVE A BIG IMPACT ON
TEMPERATURES BOTH DAY AND NIGHT. LOWS SATURDAY MORNING WILL BE ABOVE
FREEZING IN MANY AREAS UNDER HEAVY STRATUS. NEAR OR ABOVE FREEZING
LOWS ARE EXPECTED EAST OF HIGHWAY 83 FRIDAY MORNING. HIGHS FRIDAY
AND SATURDAY HAVE BEEN LOWERED EAST OF HIGHWAY 83 WHERE LOW CLOUDS
ARE EXPECTED TO INTERFERE WITH THE HEATING CYCLE. HIGH CLOUDS WEST
SATURDAY WOULD ALSO HOLD DOWN TEMPERATURES. THE BEST GUESS ON HIGHS
FRIDAY ARE 60S WEST AND 50S EAST. 50S ARE EXPECTED ALL AREAS
SATURDAY BUT BOTH OF THESE TEMPERATURE FORECASTS ARE IN JEOPARDY
GIVEN THE TREND TOWARD GREATER CLOUD COVER IN THE MODELS.
SATURDAY NIGHT THROUGH WEDNESDAY...ALL MODELS EXCEPT THE ECM SHIFTED
THE TRACK OF THE H500 MB LOW NORTH SENDING HEAVY RAIN AND SNOW INTO
THE FCST AREA. THIS INCLUDES THE CIPS ANALOG...THE DGEX AND THE
PARALLEL GFS. THE ECM SHIFTED SOUTH OVER THE PREVIOUS RUN BUT STILL
INDICATES VERY GOOD MOISTURE TRANSPORT INTO THE FCST AREA EVEN
THOUGH THE PCPN FIELDS WOULD INDICATE OTHERWISE. POPS FOR SUNDAY
THROUGH MONDAY ARE 40 TO 50 PERCENT FOR THIS FORECAST AND LATER
FORECASTS CAN MARK THESE UP AS WARRANTED. THE LONG WAVE TROF WILL
COME ASHORE THE WEST COAST TONIGHT AND THE UPPER AIR NETWORK SHOULD
GET REASONABLY GOOD SAMPLING TO IMPROVE MODEL CONSENSUS STORM TRACK.
THE PTYPE IS RAIN CHANGING TO SNOW DURING THE DAY AND EVENING
SUNDAY. THE ECM...THE SLOWEST MODEL...SHOWS COLD AIR DROPPING INTO
WESTERN NEB AROUND NOON SUNDAY WHICH SHOULD CAUSE A CHANGEOVER TO
SNOW WEST OF HIGHWAY 83. THE GEM AND GFS ARE A BIT FASTER WITH THE
CHANGEOVER. ALL MODELS SHOW FREEZING RAIN AND SLEET ALONG OR NEAR
THE CHANGEOVER LINE AT SOME POINT...MAINLY SUNDAY NIGHT AND MONDAY.
H700MB ARE BELOW ZERO A DEGREE OR TWO SO THIS APPEARS UNLIKELY AT
THIS TIME.
TEMPERATURES WOULD LIKELY FALL OR REMAIN STEADY SUNDAY IN THE 30S
AND 40S. THERE IS A GOOD CHANCE THAT ARCTIC HIGH PRESSURE WILL FILL
IN BEHIND THE STORM MONDAY THROUGH WEDNESDAY. THE ECM AND TO A
LESSER EXTENT THE GFS...STILL SHOW THIS AIR STILL IN PLACE ON
WEDNESDAY. THUS HIGHS IN THE 30S AND LOWS IN THE TEENS AND SINGLE
DIGITS SHOULD PREVAIL ONCE THE STORM EXITS THE CNTL PLAINS LATE
MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 619 PM CST WED DEC 10 2014
IFR CONDITIONS HAVE BEEN INTRODUCED TO THE FORECAST AT KLBF AFTER
06Z. FORECAST 4SM BKN007 AFTER 08Z UNTIL 15Z. CONDITIONS COULD
BECOME LIFR ACCORDING TO LATEST HRRR AND RAP13 MESSCALE MODEL
FORECASTS. AT KVTN VFR CONDITIONS TO PREVAIL AS THE STRATUS AND
FOG WILL REMAIN EAST OF THE TERMINAL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CDC
SHORT TERM...TAYLOR
LONG TERM...CDC
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
546 PM CST WED DEC 10 2014
.SHORT TERM... (THIS EVENING THROUGH THURSDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THE PRIMARY FORECAST CONCERN WILL CENTER AROUND THE PROBABILITY OF
DENSE FOG AS EARLY AS THIS EVENING AND POSSIBLY PERSISTING UNTIL MID
MORNING ON THURSDAY. THERE IS THEN CONCERN AS TOO HOW QUICKLY THE
FOG AND LOW CLOUDS WILL SCATTER OUT OR IF WE WILL EVEN SEE ANY
SUNSHINE...WHICH HAS SIGNIFICANT IMPLICATIONS ON OUR THURSDAY HIGH
TEMPERATURE FORECAST.
TONIGHT...THE HRRR AND SREF BOTH INDICATE A MODEST CHANCE OF DENSE
FOG DEVELOPMENT WEST OF INTERSTATE 80 BEGINNING THIS EVENING.
CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE A DENSE FOG ADVISORY AT THIS
TIME...BUT WOULD CERTAINLY NOT BE SURPRISED IF AT LEAST SOME LOCAL
AREAS SEE DENSE FOG TONIGHT GIVEN THE HIGH LOW LEVEL RELATIVE
HUMIDITY. THE CLOUD CEILINGS SHOULD START TO LOWER AND THE FOG
DEVELOP ONCE WE SEE DIURNAL COOLING OF THE NEAR SFC LAYER THIS
EVENING. LOW LEVEL CLOUDS AND FOG WILL KEEP TEMPERATURES UP
SOME...AND WILL BE GOING ABOVE MODEL GUIDANCE...BUT STILL BELOW
FREEZING. THEREFORE...EXPECT SOME OF THAT FROZEN FOG AGAIN TONIGHT
ACROSS THE AREA RESULTING IN MORE WHITE TREES AND PERHAPS A FEW
SLICK SPOTS ON ELEVATED SURFACES.
THURSDAY...THE FOG WILL EVENTUALLY LIFT/BURN OFF...BUT THERE IS LESS
CERTAINTY AS TO HOW QUICKLY THE FOG WILL LIFT AND IF THE CLOUDS WILL
EVEN BE ABLE TO BURN OFF ACROSS THE ENTIRE AREA. IN FACT...AM GOING
TO GO MORE PESSIMISTIC WITH FORECAST HIGHS ON THURSDAY GIVEN
INCREASING BELIEF THAT LOW CLOUDS WILL HOLD THROUGH MUCH OF THE DAY
IF NOT ALL OF THE DAY FOR MANY LOCATIONS. EVEN IF THE LOW CLOUDS
BREAK UP SOME BY AFTERNOON...THERE WILL BE LITTLE TIME FOR MUCH
WARMING TO OCCUR. THE NAM MODEL HAS BEEN RATHER CONSISTENT WITH HIGH
RH VALUES INDICATIVE OF A LOW CLOUD DECK FROM AROUND 900 MB TO THE
SFC. THE CLOUD DECK SHOULD NOT BE THICK ENOUGH TO PRODUCE
DRIZZLE...BUT WILL IMPACT HIGHS. THEREFORE...WILL NOW BE CALLING FOR
FORECAST HIGHS IN THE LOWER 40S EAST OF HWY 281 TO THE MID AND UPPER
40S WEST OF HIGHWAY 281...WHICH IS A GOOD DEAL COOLER THAN WE HAD IN
THE FORECAST A FEW DAYS AGO.
.MID TERM...(THURSDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THIS 48-HOUR PERIOD IS EFFECTIVELY THE "RELATIVE CALM" BEFORE THE
POTENTIALLY MORE IMPACTFUL SUNDAY-MONDAY STORM SYSTEM DESCRIBED IN
THE LONG-TERM SECTION BELOW. EVEN SO...THIS IS LOOKING LIKE A
LARGELY DREARY...AND AT TIMES FOGGY/DRIZZLY PERIOD...AND THE ODDS OF
SEEING MUCH SUNSHINE ON FRIDAY AND SATURDAY ARE LOOKING PRETTY SLIM.
DESPITE THE OVERALL-GLOOMY WEATHER PATTERN...AT LEAST TEMPERATURES
WILL BE ON THE SEASONABLY MILD SIDE...WITH HIGHS FRI/SAT CURRENTLY
AIMED INTO THE 50S...AND LOWS FRIDAY NIGHT HOLDING UP INTO THE 40S
MOST AREAS...POTENTIALLY SETTING RECORD WARM LOW TEMPS FOR DEC. 13TH
AT OUR PRIMARY CLIMATE RECORD SITES GRAND ISLAND/HASTINGS. DESPITE
THE MILDER READINGS...THIS FORECAST CONTINUES THE TREND FROM
PREVIOUS ISSUANCES OF SHAVING ANOTHER 2-3 DEGREES OFF HIGHS
FRIDAY/SATURDAY...AND AS EVIDENCED BY WHAT HAPPENED JUST TODAY...ITS
QUITE POSSIBLE THAT FURTHER DOWNWARD ADJUSTMENTS MAY BE NEEDED IF
AREAS REMAIN SOCKED IN UNDER LOW STRATUS.
IN TERMS OF WEATHER HAZARDS...FORTUNATELY ANY DRIZZLE/LIGHT RAIN
THAT FALLS DURING THIS TIME FRAME SHOULD BE OF THE NON-FREEZING
VARIETY. THAT LEAVES NIGHT-TIME/MORNING FOG AS THE PARAMOUNT
CONCERN...AND WHETHER OR NOT IT BECOMES DENSE (VISIBILITY 1/4 MILE
OR LESS). ALTHOUGH THERE ARE SUGGESTIONS IN NAM/SREF VISIBILITY
PROGS THAT DENSE FOG IS A POSSIBILITY BOTH NIGHTS IN AT LEAST PARTS
OF THE CWA...ITS JUST TOO SOON TO PINPOINT WITH ANY CONFIDENCE...SO
WILL CALL FOR GENERIC "PATCHY" OR "AREAS" OF FOG AT THIS TIME AND
MENTION IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID) THAT VISIBILITY
REDUCTIONS TO LESS THAN 1 MILE ARE POSSIBLE (IF NOT PROBABLE).
GETTING INTO MORE DETAIL NOW IN 12-HOUR BLOCKS...
THURSDAY EVENING/NIGHT...THE BIG MID-UPPER LEVEL PICTURE FEATURES A
SEEMINGLY "QUIET" PATTERN WITH THE CENTRAL PLAINS DOMINATED BY A
LARGE SCALE RIDGE. HOWEVER...THERE IS MORE GOING ON DOWN CLOSER TO
THE SURFACE. MADE LITTLE CHANGE FROM PREVIOUS FORECAST HERE...AS
HAVE MAINTAINED EITHER A PATCHY OR AREAS OF FOG MENTION THROUGHOUT
THE NIGHT...AS MOIST SOUTHERLY FLOW PERSISTS. THE PRESENCE OF LIGHT-
BUT-STEADY 5-10 MPH BREEZES COULD WORK AGAINST WIDESPREAD DENSE FOG
ISSUES...BUT THAT IS YET TO BE SEEN. AS FOR DRIZZLE POTENTIAL...IT
IS LOOKING A BIT LESS FAVORABLE THAN IT DID 24 HOURS AGO DUE TO THE
DEPTH OF SATURATION TOPPING OUT CLOSER TO ONE-HALF KILOMETER (KM)
THAN 1 KM IN THE LATEST NAM FORECAST SOUNDINGS...BUT WAS UNWILLING
TO YANK IT FROM THE FORECAST YET AND WILL LET NEXT FEW SHIFTS TAKE
ANOTHER LOOK. DID HOWEVER "DOWNGRADE" THE PROBABILITY OF DRIZZLE
FROM CHANCE TO SLIGHT CHANCE...AND KEPT IT IN KS ZONES ONLY PRE-
MIDNIGHT...BEFORE EXPANDING IT NORTHWARD ACROSS THE MAJORITY OF NEB
ZONES POST-MIDNIGHT. ALL IN ALL THOUGH...FOG SHOULD BE MORE
PREVALENT THAN DRIZZLE. MADE LITTLE CHANGE TO LOW TEMPS...KEEPING
MOST OF THE CWA UP INTO THE MID- UPPER 30S...EXCEPT FOR COLDER
READINGS CLOSER TO 30 IN FAR NORTHERN/WESTERN COUNTIES.
FRIDAY DAYTIME...THE HEART OF THE MID-UPPER LEVEL RIDGE AXIS
TRANSITIONS OVER THE LOCAL AREA...BUT DOWN LOW THE STORY REMAINS
MUCH THE SAME. LEANING TOWARD THE 12Z NAM DEPICTION MORE THAN
ANYTHING...WIDESPREAD LOW STRATUS CLOUDS SHOULD CONTINUE TO
ENCOMPASS MOST IF NOT ALL OF THE CWA...AND EVEN THOUGH SKY COVER WAS
INCREASED IT COULD PROBABLY TREND HIGHER. OF COURSE...BRIEF POCKETS
OF SUNSHINE CANNOT BE COMPLETELY RULED OUT EITHER. SOUTHERLY BREEZES
GENERALLY 10-15 MPH WILL PREVAIL THROUGH THE DAY. AS FOR FOG/DRIZZLE
POTENTIAL...CONTINUED BOTH OF THESE ELEMENTS INTO THE FRIDAY MORNING
HOURS OUT OF THURSDAY NIGHT...BUT BASED ON THE LACK OF "SPLOTCHY
QPF" INDICATED BY THE 12Z NAM DURING THE AFTERNOON HOURS HAVE OPTED
TO KEEP FRIDAY AFTERNOON DRIZZLE/FOG FREE AT LEAST FOR NOW. AS
MENTIONED ABOVE...MADE MINOR DOWNWARD TWEAKS TO HIGH TEMPS...BUT
STILL AIMING FROM LOW 50S NORTHEAST TO MAINLY MID 50S SOUTHWEST.
FRIDAY NIGHT...BY THIS TIME THE LARGE SCALE RIDGE AXIS IS STARTING
TO DEPART EAST OF THE AREA...BUT THE LARGE/AMPLIFIED WESTERN TROUGH
STILL REMAINS WELL-WEST...WITH THE BASE OF THIS TROUGH ONLY REACHING
THE SOUTHERN CA/AZ BORDER AREA BY SUNRISE SATURDAY. NEAR/AT THE
SURFACE...THE SAME MOIST/WIDESPREAD CLOUDY AIRMASS CONTINUES...AND
BY THIS TIME MOISTURE DEPTH SHOULD BE INCREASING ENOUGH TO MAKE
DRIZZLE MORE LIKELY AND HAVE GONE WITH "CHANCE" WORDING HERE INSTEAD
OF JUST SLIGHT CHANCE AS THE NIGHT BEFORE. ALSO BLANKETED THE ENTIRE
CWA WITH AREAS OF FOG POTENTIAL. ASSUMING THAT TEMPS DURING THE
PRECEDING DAY WARM AS MUCH AS PROGGED...THERE SHOULD BE VERY LITTLE
DROP-OFF FRIDAY NIGHT...AND HAVE QUITE-MILD LOWS AIMED INTO THE LOW-
MID 40S MOST AREAS.
SATURDAY DAYTIME...IN SOME WAYS THIS RESEMBLES A SOMEWHAT
MILD/"HUMID" EARLY SPRING DAY...AS SURFACE DEWPOINTS ARE CURRENTLY
AIMED TO RISE WELL INTO THE MID-UPPER 40S AND POTENTIALLY EVEN LOW
50S IN SOME PLACES. ALTHOUGH THE MAIN VORT MAX WITHIN THE EXPANSIVE
WESTERN CONUS LOW CONTINUES TO SLOWLY APPROACH...CURRENT
NAM/GFS/ECMWF RUNS ONLY BRING IT TO NEAR THE 4-CORNERS AREA BY DAYS
END...WITH LITTLE IF ANY LARGE-SCALE FORCING INFLUENCING THE CENTRAL
PLAINS YET. THIS MEANS THAT ANY PRECIP CHANCES WILL CONTINUE TO BE
DRIVEN BY SHALLOW PROCESSES WITHIN THE LAYER STRATUS DECK. COMPARED
TO THE PREVIOUS 24-36 HOURS...SATURDAY DAYTIME APPEARS TO HAVE THE
BEST POTENTIAL FOR A MORE WIDESPREAD/POTENTIALLY EVEN MEASURABLE
DRIZZLE/LIGHT RAIN ACROSS MUCH OF THE AREA...AND THUS OPTED TO
CONTINUE AN OFFICIAL 20 PERCENT MEASURABLE POP IN THIS PERIOD. AS
WITH FRIDAY...SHAVED A FEW DEGREES OFF HIGHS AND MAYBE NOT QUITE
ENOUGH...BUT NOW HAVE MID-UPPER 50S ACROSS THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THE START OF THE LONG TERM PERIOD...00Z SUNDAY...HAS NOT SEEN ANY
SIGNIFICANT CHANGES IN THE MODELS...WITH A WELL AMPLIFIED PATTERN IN
PLACE ACROSS THE CONUS...AS RIDGING EXTENDS FROM ERN TX NORTH INTO
ONTARIO...WHILE TROUGHING DIGS SOUTH THROUGH THE ROCKIES. THE MAIN
UPPER LEVEL LOW PRESSURE SYSTEM WHICH WILL BEAR WATCHING IN THE
COMING DAYS IS EXPECTED TO BE IN PLACE OVER THE FOUR CORNERS REGION.
AT THE SURFACE...LOW PRESSURE REMAINS IN PLACE OVER ERN PORTIONS OF
CO...WITH A TROUGH AXIS EXTENDING N/NE INTO THE DAKOTAS...KEEPING
THE SOUTHERLY WINDS GOING ACROSS THE CWA. THE STREAM OF INCREASED
WARM AIR/MOISTURE ADVECTION NORTH INTO THE AREA...KEEPING PLENTY OF
LOW LEVEL CLOUD COVER AROUND...ALONG WITH THE CONTINUED POTENTIAL
DRIZZLE/LIGHT RAIN. OVERNIGHT LOWS SAT NIGHT/SUN MORNING WILL BE
MILD WITH 40S AND A FEW 50S CURRENTLY FORECAST.
SUNDAY AND MONDAY CERTAINLY THE MOST INTERESTING TIME TIME FRAME OF
THE PERIOD...AS WE SEE THE ARRIVAL OF THAT UPPER LEVEL LOW PRESSURE
SYSTEM...AND THE POTENTIAL FOR ACCUMULATING SNOWFALL. DURING THE
DAYTIME HOURS ON SUNDAY...THE LOW IS EXPECTED TO EMERGE OUT OF THE
ROCKIES AND ONTO THE PLAINS...ENDING UP BY 00Z MONDAY ROUGHLY OVER
THE OK/TX PANHANDLE AREA. HOW IT EVOLVES BEYOND THAT AND WHERE ITS
ULTIMATE TRACK ENDS UP WILL DRIVE WHAT OUR CWA SEES SUNDAY NIGHT
THROUGH MONDAY /PERHAPS LINGERING INTO MONDAY NIGHT?/.
PLENTY OF UNCERTAINTY REMAINS WITH THIS SYSTEM. PREVIOUS MODEL RUNS
HAD GENERALLY TAKEN THE SYSTEM ALONG A MORE SOUTHERLY PATH...LEAVING
OUR CWA MORE ON THE NRN EDGE OF THE MAIN ACTIVITY. LOOKING AT THE
12Z RUN OF MODELS TODAY...THE GFS/GEM HAVE A MORE NRN TRACK THROUGH
MONDAY MORNING...TAKING THE 500 AND ESP 700MB LOWS ACROSS CENTRAL
KS...IF NOT RIGHT OVER OUR SRN CWA...AND USHERS IN COLDER
AIR/TRANSITION TO SNOW EVERYWHERE QUICKER. THE LATEST RUN OF THE
ECMWF HOWEVER KEEPS THE TRACK MORE OVER NRN OK...AND IS A TOUCH
SLOWER WITH THE COLDER AIR. THE START OF THIS EVENT IS STILL 4 DAYS
OUT...SO PLENTY EARLY TO BE BUYING FULL IN TO ANY PARTICULAR MODEL
OR MODEL RUN...AS 24 HRS FROM NOW THEY MAY LOOK DIFFERENT.
HOWEVER...EITHER SOLUTION WOULD RESULT IN ACCUMULATING SNOWFALL FOR
THE CWA...DIFFERENCE IS IN WHERE THE HEAVIER /SEVERAL INCHES
POTENTIALLY/ COULD END UP. COMBINED WITH THE EXPECTED GUSTY
NORTHWEST WINDS BUILDING IN BEHIND A PASSING COLD...THOSE WITH
TRAVEL PLANS DURING THIS PERIOD REALLY NEED TO KEEP A CLOSE EYE ON
THE FORECAST IN THE COMING DAYS...LOT OF DETAILS YET TO BE IRONED
OUT. AS FAR AS HIGH TEMPERATURES GO...ON SUNDAY AHEAD OF THE FRONTAL
PASSAGE...HIGHS IN THE MID 40S TO MID 50S ARE CURRENTLY IN THE
FORECAST...WITH LOWER/MID 30S GOING FOR MONDAY.
DRY CONDITIONS RETURN TO THE FORECAST FOR TUESDAY AND WEDNESDAY...AS
UPPER LEVEL SHORTWAVE RIDGING BUILDS IN BEHIND THIS STORM SYSTEM.
CONFIDENCE IN TEMPS IS NOT HIGH....NOT EXPECTING A NOTABLE CHANGE IN
THE OVERALL AIR MASS...BUT SNOWFALL ON THE GROUND WOULD COMPLICATE
THINGS. CURRENT FORECAST HIGHS BOTH DAYS REMAIN IN THE 30S.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 533 PM CST WED DEC 10 2014
GENERALLY POOR AVIATION CONDITIONS ARE EXPECTED FOR THE NEXT 24
HOURS WITH LOW LEVEL STRATUS AND FOG PERSISTING THROUGH JUST
ABOUT THE ENTIRE PERIOD. EXPECT CIGS AND VSBYS TO DETERIORATE
QUICKLY OVER THE NEXT HOUR OR SO...WITH LIFR CONDITIONS BECOMING
LIKELY AFTER ABOUT MIDNIGHT. WITH PERSISTENT LIGHT SOUTH
SOUTHEASTERLY FLOW CONTINUING OVERNIGHT...ONCE LIFR CONDITIONS
DEVELOP...DO NOT EXPECT MUCH IMPROVEMENT UNTIL A FEW HOURS AFTER
SUNRISE THURSDAY MORNING. MAY SEE SOME SUN BREAK OUT AT EAR NEAR
THE END OF THE PERIOD AS THE WINDS TURN MORE SOUTHERLY...AND
INTRODUCED VFR CONDITIONS THERE AFT 11/21Z. MVFR CIGS ARE EXPECTED
TO REMAIN AT KGRI AS THE STRATUS IS EXPECTED TO BE MORE PERSISTENT
THE FURTHER EAST YOU GO.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...WESELY
LONG TERM...ADP
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1221 PM CST TUE DEC 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CST TUE DEC 9 2014
SYNOPTIC ANALYSIS OVERNIGHT INDICATES THE UPPER LEVEL TROUGH
CONTINUING TO SHIFT ACROSS THE OHIO RIVER VALLEY WHILE AN UPPER
LEVEL RIDGE HAS BEGUN TO BUILD ACROSS THE ROCKY MOUNTAINS. ALOFT...A
100+ KT JET CAN BE SEEN DIVING SOUTH ACROSS IOWA AND WESTERN
MISSOURI AROUND THE BASE OF THE TROUGH. IN THE MID LEVELS...HEIGHT
RISES SUGGEST THE BUILDING OF THE MID LEVEL RIDGE ACROSS THE
MIDWEST...AND SOME MINIMAL MID LEVEL MOISTURE PRESENT ACROSS THE
PLAINS. AT THE SURFACE...LOW PRESSURE CAN BE SEEN ACROSS THE GREAT
LAKES WHILE A LARGE AREA OF HIGH PRESSURE BEGINS TO SPREAD FROM
MANITOBA STRETCHING SOUTH INTO NEBRASKA. LATEST SATELLITE IMAGERY
SHOWS A LARGE AREA OF STRATUS CIRCULATING UNDER THE UPPER LEVEL
LOW...WITH STRATUS BANDS STRETCHING INTO PORTIONS OF CENTRAL
NEBRASKA. UNDER THESE BANDS...METAR SITES HAVE INDICATED CEILING
HEIGHTS NEAR 1500 FT AND VISIBILITIES AS LOW AS 1/4 MILE AT
VALENTINE.
FOR THE VERY NEAR SHORT TERM...THESE STRATUS BANDS WILL BE OF
CONCERN. SHORT TERM MODELS SUCH AS THE RAP...SREF...AND HRRR ALL
SUGGEST THAT REDUCED VISIBILITIES WILL BE VERY CLOSE TO OUR WESTERN
BORDER...WHILE THE GFS REMAINS DRY. AT THIS TIME...CONTINUED WITH
AREAS OF FOG IN THE FORECAST...BUT WILL CONTINUE TO MONITOR IN CASE
A DENSE FOG ADVISORY IS NEEDED. AS SUCH...AS THE HIGH PRESSURE/RIDGE
AXIS SWINGS THROUGH THE PLAINS...EXPECT WINDS TO SWITCH TO SOUTHERLY
AND HELP CLEAR OUT ANY FOG THAT DOES DEVELOP BY MID TO LATE MORNING.
THE MAIN FOCUS OF THE REST OF THE SHORT TERM PERIOD WILL CENTER ON
THE POSSIBILITY FOR FREEZING DRIZZLE AND FOG OVERNIGHT AND INTO
WEDNESDAY MORNING. AN UPPER LEVEL SHORT WAVE DISTURBANCE WILL
DEVELOP ACROSS THE NORTHERN ROCKIES AND SWING THROUGH THE CENTRAL
PLAINS OVERNIGHT. AT THE SURFACE...LIGHT SOUTH WINDS WILL SURGE LOW
LEVEL MOISTURE NORTHWARD ACROSS MUCH OF THE AREA. THIS COMBINED WITH
LIFT FROM THE UPPER LEVEL DISTURBANCE SHOULD PROMOTE FOG
DEVELOPMENT. HOWEVER...SOUNDINGS INDICATE VERY DRY MID LEVELS AND
BOTH THE NAM AND GFS SOLUTIONS SUGGESTING HIGHER BULK SHEAR VALUES
NEAR 10 KTS...ESPECIALLY ACROSS NORTH CENTRAL KANSAS AND THE STATE
LINE. THEREFORE...IT REMAINS A STRONG POSSIBILITY OF FREEZING
DRIZZLE ACROSS NORTH CENTRAL KANSAS AND SOUTHERN NEBRASKA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CST TUE DEC 9 2014
THE MODELS CONTINUE TO HAVE THE MOISTURE ACROSS THE AREA DURING THE
DAY WEDNESDAY AND EVEN INTO WEDNESDAY NIGHT. EXPECT THE FOG AND
FREEZING DRIZZLE FROM TUESDAY NIGHT TO CONTINUE INTO WEDNESDAY
MORNING. AS TEMPERATURES WARM DURING THE MORNING THE FREEZING
DRIZZLE SHOULD BECOME DRIZZLE. THE PRECIPITATION SHOULD REMAIN
MAINLY IN THE SOUTHEAST PART OF THE FORECAST AREA. WILL CONTINUE
WITH DRIZZLE IN THE SOUTHEAST DURING THE AFTERNOON. THE ONLY MODEL
THAT MOVES THE MOISTURE OFF TO THE EAST IS THE GFS...SO WILL KEEP
THE DRIZZLE INTO THE NIGHT TIME HOURS. IT SHOULD BE IN THE SOUTHEAST
AND SHOULD GRADUALLY END FROM WEST TO EAST DURING THE NIGHT.
THURSDAY AND BEYOND THE MODELS HAVE SEVERAL DIFFERENCES IN TIMING
AND STRENGTH OF THE SYSTEMS AND EVEN SOME RUN TO RUN
INCONSISTENCIES.
THERE IS AN UPPER LEVEL RIDGE THAT WILL MOVE THROUGH THE AREA
THURSDAY AND FRIDAY. EXPECT THE TEMPERATURES TO WARM UP AS THERE
WILL BE PARTLY CLOUDY SKIES AND WARM ADVECTION.
AN UPPER LEVEL SYSTEM IN THE ROCKIES WITH A DEVELOPING SURFACE LOW
ON THE HIGH PLAINS WILL BRING MOISTURE BACK TO THE AREA ON SATURDAY.
THERE WILL BE WARM ADVECTION AND TEMPERATURES WILL BE WARM ON
SATURDAY. THE SURFACE LOW AND COLD FRONT WILL MOVE THROUGH THE
FORECAST AREA SATURDAY NIGHT. THE COOLER AIR STARTS TO MOVE INTO THE
AREA ON SUNDAY AND TEMPERATURES WILL BE A LITTLE COOLER THAN
SATURDAY. THE QUESTION BECOMES PRECIPITATION CHANCES. FORECAST
SOUNDINGS SHOW THAT THERE WILL BE A DRY LAYER AND HAVE KEPT
PRECIPITATION IN THE SOUTHEAST...BUT THAT IS EVEN A LITTLE
QUESTIONABLE. BY SATURDAY NIGHT THE MID LEVELS MOISTEN UP SOME AND
THERE WILL BE A FEW MORE CLOUDS WITH MAYBE SOME RAIN IN THE EAST.
SUNDAY AND SUNDAY NIGHT LOOK LIKE BETTER CHANCES FOR SOME
PRECIPITATION. THIS IS THE FIRST RUN WHERE THE GFS AND THE ECMWF ARE
A LITTLE MORE CONSISTENT WITH THE UPPER LOW IN THE CENTRAL TO
SOUTHERN PLAINS. THE GFS IS FASTER THAN THE ECMWF. WILL KEEP
PRECIPITATION CHANCES FOR SUNDAY AND SUNDAY NIGHT...BRINGING UP THE
QUESTION OF PRECIPITATION TYPE. SUNDAY THE TEMPERATURES SHOULD BE
WARM ENOUGH THAT EXPECT RAIN BUT TEMPERATURES AT 850MB START TO COOL
LATE IN THE AFTERNOON. DURING THE NIGHT THE TEMPERATURES CONTINUE TO
COOL AND THE RAIN SHOULD MIX WITH AND MAYBE CHANGE TO SNOW DURING
THE NIGHT. THE UPPER LOW SHOULD MOVE TO THE EAST AND EXPECT DRY AND
COOL CONDITIONS FOR MONDAY.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1145 AM CST TUE DEC 9 2014
THE PRIMARY AVIATION CONCERN WILL CENTER AROUND THE POSSIBILITY OF
LOW CLOUDS AND FOG MOVING IN LATE TONIGHT...PRIMARILY AROUND DAWN.
THERE IS A VERY SLIGHT THREAT OF LIGHT DRIZZLE OR FREEZING
DRIZZLE. HOWEVER...THE CHANCE OF ANY PRECIPITATION IS TOO LOW TO
INCLUDE IN THE TAF AT THIS POINT IN TIME. IFR VISIBILITY AND
CEILINGS WILL ALSO BE POSSIBLE WEDNESDAY MORNING FROM AROUND DAWN
THROUGHOUT THE MORNING...BUT DIFFICULT TO DETERMINE HOW LOW THE
CEILINGS AND VISIBILITY WILL GET THIS FAR OUT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1123 AM CST TUE DEC 9 2014
.SYNOPSIS...
ISSUED AT 358 AM CST TUE DEC 9 2014
H5 ANALYSIS FROM EARLIER THIS EVENING HAD A DECENT UPPER LEVEL
DISTURBANCE OVER NRN ILLINOIS WITH A TROUGH EXTENDING SWD TO THE
FLORIDA PANHANDLE. FURTHER WEST...A BROAD RIDGE EXTENDED FROM THE
INTERMOUNTAIN WEST NORTH INTO THE YUKON OF CANADA. WITHIN THIS
RIDGE...A DISTURBANCE WAS NOTED OVER WESTERN MONTANA. CURRENT WV
IMAGERY AS OF 2 AM CST HAS THIS FEATURE NOW OVER EASTERN PORTIONS
OF MT. AT THE SURFACE...AN ELONGATED AREA OF HIGH PRESSURE
EXTENDED ACROSS THE EASTERN DAKOTAS INTO EASTERN NEBRASKA. FURTHER
WEST...A TROUGH OF LOW PRESSURE WAS PRESENT OVER EASTERN WYOMING
INTO NORTHERN COLORADO. AN AREA OF STRATUS AND FOG HAS DEVELOPED
ON THE WESTERN PERIPHERY OF THE HIGH OVERNIGHT...AND THIS AREA OF
CLOUDS AND FOG EXTENDED FROM NORTH CENTRAL NEBRASKA INTO CENTRAL
AND PORTIONS OF SWRN NEBRASKA. THE FOG WAS PRIMARILY ALONG THE
WESTERN EDGE OF THE STRATUS/LOW CLOUDS AND ROUGHLY EXTENDED FROM
VALENTINE TO AINSWORTH...SWD TO THEDFORD...NORTH PLATTE AND BROKEN
BOW. FURTHER WEST...SOME HIGH CLOUDS WERE MOVING INTO THE NEBRASKA
PANHANDLE AND FAR WESTERN PORTIONS OF THE FORECAST AREA ATTM.
UNDER MOSTLY CLOUDY SKIES...TEMPERATURES AS OF 3 AM CST...RANGED
FROM 15 AT NORTH PLATTE TO 25 AT BROKEN BOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST TUE DEC 9 2014
TODAY AND TONIGHT...THE FORECAST CHALLENGES OVER THE NEXT 24
HOURS...ARE TEMPERATURES TODAY...AS WELL AS FOG POTENTIAL THIS
MORNING...AS WELL AS TONIGHT. FOR TODAY...AS MENTIONED ABOVE...FOG
HAS DEVELOPED ALONG THE HIGHWAY 83 CORRIDOR...AS WELL AS ALONG A
LINE FROM AINSWORTH TO BROKEN BOW. ATTM...THE LATEST HI RES RUC
SOLN HAS THIS AREA OF FOG EXPANDING SLIGHTLY TO THE SOUTHWEST
TOWARD DAYBREAK. ONE WILDCARD IN THE DEGREE OF WESTWARD
DEVELOPMENT OF FOG...IS THE POTENTIAL IMPACT OF HIGH LEVEL
CLOUDINESS MOVING IN FROM THE WEST. ATTM...FOG VISBYS HAVE BEEN
GENERALLY IN THE 1 TO 5 MILE RANGE...SO WILL KEEP FOG MENTION AS
PATCHY THIS MORNING. BASED ON THE HRRR SOLN...FOG SHOULD BEGIN TO
DISSIPATE DURING THE MID TO LATE MORNING TIME FRAME...AND HAVE
EXTENDED THIS MENTION OF FOG INTO THE LATE MORNING HOURS GIVEN
THIS MODEL TREND. HIGH PRESSURE WILL BEGIN TO TRACK EAST LATER
TODAY INCREASING SRLY WINDS DURING THE AFTERNOON HOURS. FOR
LOCATIONS GENERALLY WEST OF HIGHWAY 61...THE WIND DIRECTION WILL
TAKE ON A WESTERLY COMPONENT...RESULTING IN SOME LIMITED DOWNSLOPE
AND WARMER HIGHS IN THE LOWER 50S. FURTHER EAST...THE COMBINATION
OF CLOUDS...SOUTHERLY AND SOUTHEASTERLY WINDS ON THE BACK SIDE OF
THE EXITING HIGH...WILL LIMIT HIGHS IN THE UPPER 30S IN THE FAR
NORTHEAST...TO THE 40S ALONG THE HIGHWAY 83 CORRIDOR. THE LATEST
MAV GUIDANCE HAS TRENDED COLDER FOR HIGHS OVER THE PAST 3
RUNS...AND HAS COME INTO BETTER AGREEMENT WITH THE COLDER MET
GUIDANCE. WITH THIS IN MIND...TRENDED HIGHS TDY SOME 2 TO 4
DEGREES COLDER THAN THE INHERITED FCST. FOR TONIGHT...LIGHT SRLY
WINDS WILL CONTINUE...PARTICULARLY IN THE EASTERN CWA. THE LATEST
NAM SOLN IS INDICATING NEAR SATURATION IN THE BOUNDARY LAYER
OVERNIGHT TONIGHT...ROUGHLY EAST OF A LINE FROM CURTIS...TO
ONEILL. INHERITED FCST HAD A MENTION OF PATCHY FOG OVERNIGHT IN
THESE AREAS AND IT WILL BE CONTINUED WITH THE CURRENT FCST
PACKAGE. OVERNIGHT LOWS WILL BE IN THE LOWER 20S...WITH SOME UPPER
TEENS IN THE PLATTE RIVER VALLEY GIVEN THE EXPECTED LIGHT WINDS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CST TUE DEC 9 2014
12Z WEDNESDAY AND BEYOND...MODELS REMAIN IN GOOD AGREEMENT THAT
AMPLIFIED UPPER RIDGING OVER THE CENTRAL CONUS WILL EVENTUALLY BREAK
DOWN/FORCED EAST AS A LONG WAVE TROUGH DIGS INTO THE WESTERN STATES
AND EVENTUALLY THE PLAINS. TEMPERATURES UNDER THE RIDGE WILL REMAIN
ABOVE AVERAGE...AND SHOULD WARM BY SEVERAL DEGREES EACH DAY. HIGHS
BY FRIDAY ARE ANTICIPATED TO REACH INTO THE 50S TO LOWER 60S FOR
MOST AREAS...POSSIBLY WARMER IF GREATER MIXING OCCURS.
SOUTHERLY WINDS WILL HELP INCREASE LOWER LEVEL MOISTURE WHICH COULD
PROVIDE FOR PATCHY FOG EACH MORNING...WEDNESDAY THROUGH SATURDAY.
THE DETERMINISTIC SOLUTIONS GENERATE LIGHT DZ/QPF ACROSS PORTIONS OF
OUR EAST THURSDAY...FRIDAY...AND SATURDAY...BUT THE MOISTURE
PROFILES ONLY FAVOR STRATUS AND/OR FOG AS THE DEPTH OF THE RETURN IS
RATHER SHALLOW.
CONCERNING THIS WEEKEND AND A POTENTIAL SYSTEM...WHAT A DIFFERENCE A
DAY MAKES. IN 24 HOURS THE GFS SOLUTION HAS TRENDED NORTH WITH THE
TRACK OF THIS WEEKENDS CLOSED H5 LOW BY HUNDREDS OF MILES. THE
MODEL GENERATED TRACK OF THE LOW YESTERDAY FAVORED THE BIG BEND
OF TEXAS ON SUNDAY...THEREAFTER TRACKING THE LOW OVER HEART OF TEXAS
THROUGH EARLY NEXT WEEK. TONIGHT...THE GFS IS FAVORING A SOLUTION
WHICH CLOSES OFF A LOW OVER NORTHERN NEW MEXICO...THEN TRACKING THE
LOW ACROSS THE PANHANDLES OF TEXAS AND OKLAHOMA...AND EVENTUALLY
TOWARD THE MID-MISSOURI VALLEY. IT SHOULD BE NOTED THAT THE MODEL
INDICATES THE MEAN TROUGH TAKING A NEGATIVE TILT AS IT EMERGES ON
THE PLAINS. COMPLICATING MATTERS...THE EUROPEAN CAMP AND NUMEROUS
GFS ENSEMBLES SUPPORT A SIMILAR TRACK INTO THE CENTRAL PLAINS /AT
LEAST INITIALLY/. SO FOR THE FIRST SUITE OF RUNS PROGGING THIS
SYSTEM...MODEL TO MODEL CONSISTENCY IS SHOWING SOME COHERENCE...BUT
RUN TO RUN CONSISTENCY IS SEVERELY LACKING. CONFIDENCE IN ANY ONE
PARTICULAR SOLUTION IS LOW...ESPECIALLY SINCE ALL LONG TERM GUIDANCE
GENERATES CONVECTION ACROSS THE SOUTHERN PLAINS AND TEXAS ON SUNDAY.
THE GFS SEEMS TO BE KEYING ON THE CONVECTIVE POTENTIAL...GENERATING
AN AREA OF PV DESTRUCTION OVER OUR SOUTH...AND SEVERELY LIMITING THE
QPF POTENTIAL ACROSS MUCH THE CWA. THE GFS HOWEVER DOES EVENTUALLY
GENERATE WRAP AROUND QPF SUNDAY AFTERNOON/EVENING ACROSS OUR SOUTH
AND EAST. THE WRAP AROUND IS IN QUESTION AS THE CONVECTION
/PROJECTED TO BE OVER EASTERN KANSAS/ WOULD ALLOW FOR AN ASSUMED
GREATER EASTWARD WOBBLE OF THE H7 LOW. SO INSTEAD OF THE MODEL
PROJECTED H7 LOW OVER NORTH CENTRAL KANSAS...THE MORE LIKELY
LOCATION WOULD BE EASTERN OR SOUTHEASTERN KANSAS. THE WRAP AROUND
WOULD THUS BE SHUNTED SOUTHEAST AS WELL. THE ECMWF IS
CONCERNING...GENERATING SIGNIFICANT SNOW ACROSS OUR SOUTHERN TIER ON
SUNDAY...BUT AGAIN...THE CONVECTION THAT THE MODEL IS GENERATING
PUTS ANY OF THE QPF ACROSS OUR CWA SEVERELY IN QUESTION. THE CR-INT
PROCEDURE REMAINS PESSIMISTIC IN THE QPF DEPARTMENT FOR SUNDAY AND
BEYOND...WHICH IS FAVORED AT THIS POINT...NO CHANGES WERE MADE TO
THE BLENDED FORECAST. BUT...LAST NIGHT MY FORECAST STATED THE
POTENTIAL WEEKEND STORM WAS LOOKING MORE LIKE A "DUD" FOR THE
CWA...AT THIS TIME I WISH TO RETRACT THOSE WORDS AND STATE THAT THIS
SYSTEM IS CERTAINLY WORTH WATCHING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1110 AM CST TUE DEC 9 2014
CURRENTLY PATCHY FOG AND LOW STRATUS IS OCCURRING TO THE EAST OF
THE HWY 83 CORRIDOR...THIS WILL NOT AFFECT THE KVTN OR KLBF SITES
AS THE COVERAGE SHOULD STAY OFF TO THE EAST AND CONTINUE TO
DISSIPATE DURING THE AFTERNOON HOURS. VFR CONDITIONS ARE EXPECTED
AS BROKEN HIGH CLOUDS WILL PERSIST THROUGH MUCH OF THE DAY. WINDS
WILL SHIFT OVERNIGHT FROM THE SOUTH TO THE SOUTHWEST AND SKIES
WILL BE MOSTLY CLEAR THROUGH THE OVERNIGHT INTO TOMORROW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...JACOBS
AVIATION...GOMEZ
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
557 AM CST TUE DEC 9 2014
.SYNOPSIS...
ISSUED AT 358 AM CST TUE DEC 9 2014
H5 ANALYSIS FROM EARLIER THIS EVENING HAD A DECENT UPPER LEVEL
DISTURBANCE OVER NRN ILLINOIS WITH A TROUGH EXTENDING SWD TO THE
FLORIDA PANHANDLE. FURTHER WEST...A BROAD RIDGE EXTENDED FROM THE
INTERMOUNTAIN WEST NORTH INTO THE YUKON OF CANADA. WITHIN THIS
RIDGE...A DISTURBANCE WAS NOTED OVER WESTERN MONTANA. CURRENT WV
IMAGERY AS OF 2 AM CST HAS THIS FEATURE NOW OVER EASTERN PORTIONS
OF MT. AT THE SURFACE...AN ELONGATED AREA OF HIGH PRESSURE
EXTENDED ACROSS THE EASTERN DAKOTAS INTO EASTERN NEBRASKA. FURTHER
WEST...A TROUGH OF LOW PRESSURE WAS PRESENT OVER EASTERN WYOMING
INTO NORTHERN COLORADO. AN AREA OF STRATUS AND FOG HAS DEVELOPED
ON THE WESTERN PERIPHERY OF THE HIGH OVERNIGHT...AND THIS AREA OF
CLOUDS AND FOG EXTENDED FROM NORTH CENTRAL NEBRASKA INTO CENTRAL
AND PORTIONS OF SWRN NEBRASKA. THE FOG WAS PRIMARILY ALONG THE
WESTERN EDGE OF THE STRATUS/LOW CLOUDS AND ROUGHLY EXTENDED FROM
VALENTINE TO AINSWORTH...SWD TO THEDFORD...NORTH PLATTE AND BROKEN
BOW. FURTHER WEST...SOME HIGH CLOUDS WERE MOVING INTO THE NEBRASKA
PANHANDLE AND FAR WESTERN PORTIONS OF THE FORECAST AREA ATTM.
UNDER MOSTLY CLOUDY SKIES...TEMPERATURES AS OF 3 AM CST...RANGED
FROM 15 AT NORTH PLATTE TO 25 AT BROKEN BOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST TUE DEC 9 2014
TODAY AND TONIGHT...THE FORECAST CHALLENGES OVER THE NEXT 24
HOURS...ARE TEMPERATURES TODAY...AS WELL AS FOG POTENTIAL THIS
MORNING...AS WELL AS TONIGHT. FOR TODAY...AS MENTIONED ABOVE...FOG
HAS DEVELOPED ALONG THE HIGHWAY 83 CORRIDOR...AS WELL AS ALONG A
LINE FROM AINSWORTH TO BROKEN BOW. ATTM...THE LATEST HI RES RUC
SOLN HAS THIS AREA OF FOG EXPANDING SLIGHTLY TO THE SOUTHWEST
TOWARD DAYBREAK. ONE WILDCARD IN THE DEGREE OF WESTWARD
DEVELOPMENT OF FOG...IS THE POTENTIAL IMPACT OF HIGH LEVEL
CLOUDINESS MOVING IN FROM THE WEST. ATTM...FOG VISBYS HAVE BEEN
GENERALLY IN THE 1 TO 5 MILE RANGE...SO WILL KEEP FOG MENTION AS
PATCHY THIS MORNING. BASED ON THE HRRR SOLN...FOG SHOULD BEGIN TO
DISSIPATE DURING THE MID TO LATE MORNING TIME FRAME...AND HAVE
EXTENDED THIS MENTION OF FOG INTO THE LATE MORNING HOURS GIVEN
THIS MODEL TREND. HIGH PRESSURE WILL BEGIN TO TRACK EAST LATER
TODAY INCREASING SRLY WINDS DURING THE AFTERNOON HOURS. FOR
LOCATIONS GENERALLY WEST OF HIGHWAY 61...THE WIND DIRECTION WILL
TAKE ON A WESTERLY COMPONENT...RESULTING IN SOME LIMITED DOWNSLOPE
AND WARMER HIGHS IN THE LOWER 50S. FURTHER EAST...THE COMBINATION
OF CLOUDS...SOUTHERLY AND SOUTHEASTERLY WINDS ON THE BACK SIDE OF
THE EXITING HIGH...WILL LIMIT HIGHS IN THE UPPER 30S IN THE FAR
NORTHEAST...TO THE 40S ALONG THE HIGHWAY 83 CORRIDOR. THE LATEST
MAV GUIDANCE HAS TRENDED COLDER FOR HIGHS OVER THE PAST 3
RUNS...AND HAS COME INTO BETTER AGREEMENT WITH THE COLDER MET
GUIDANCE. WITH THIS IN MIND...TRENDED HIGHS TDY SOME 2 TO 4
DEGREES COLDER THAN THE INHERITED FCST. FOR TONIGHT...LIGHT SRLY
WINDS WILL CONTINUE...PARTICULARLY IN THE EASTERN CWA. THE LATEST
NAM SOLN IS INDICATING NEAR SATURATION IN THE BOUNDARY LAYER
OVERNIGHT TONIGHT...ROUGHLY EAST OF A LINE FROM CURTIS...TO
ONEILL. INHERITED FCST HAD A MENTION OF PATCHY FOG OVERNIGHT IN
THESE AREAS AND IT WILL BE CONTINUED WITH THE CURRENT FCST
PACKAGE. OVERNIGHT LOWS WILL BE IN THE LOWER 20S...WITH SOME UPPER
TEENS IN THE PLATTE RIVER VALLEY GIVEN THE EXPECTED LIGHT WINDS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CST TUE DEC 9 2014
12Z WEDNESDAY AND BEYOND...MODELS REMAIN IN GOOD AGREEMENT THAT
AMPLIFIED UPPER RIDGING OVER THE CENTRAL CONUS WILL EVENTUALLY BREAK
DOWN/FORCED EAST AS A LONG WAVE TROUGH DIGS INTO THE WESTERN STATES
AND EVENTUALLY THE PLAINS. TEMPERATURES UNDER THE RIDGE WILL REMAIN
ABOVE AVERAGE...AND SHOULD WARM BY SEVERAL DEGREES EACH DAY. HIGHS
BY FRIDAY ARE ANTICIPATED TO REACH INTO THE 50S TO LOWER 60S FOR
MOST AREAS...POSSIBLY WARMER IF GREATER MIXING OCCURS.
SOUTHERLY WINDS WILL HELP INCREASE LOWER LEVEL MOISTURE WHICH COULD
PROVIDE FOR PATCHY FOG EACH MORNING...WEDNESDAY THROUGH SATURDAY.
THE DETERMINISTIC SOLUTIONS GENERATE LIGHT DZ/QPF ACROSS PORTIONS OF
OUR EAST THURSDAY...FRIDAY...AND SATURDAY...BUT THE MOISTURE
PROFILES ONLY FAVOR STRATUS AND/OR FOG AS THE DEPTH OF THE RETURN IS
RATHER SHALLOW.
CONCERNING THIS WEEKEND AND A POTENTIAL SYSTEM...WHAT A DIFFERENCE A
DAY MAKES. IN 24 HOURS THE GFS SOLUTION HAS TRENDED NORTH WITH THE
TRACK OF THIS WEEKENDS CLOSED H5 LOW BY HUNDREDS OF MILES. THE
MODEL GENERATED TRACK OF THE LOW YESTERDAY FAVORED THE BIG BEND
OF TEXAS ON SUNDAY...THEREAFTER TRACKING THE LOW OVER HEART OF TEXAS
THROUGH EARLY NEXT WEEK. TONIGHT...THE GFS IS FAVORING A SOLUTION
WHICH CLOSES OFF A LOW OVER NORTHERN NEW MEXICO...THEN TRACKING THE
LOW ACROSS THE PANHANDLES OF TEXAS AND OKLAHOMA...AND EVENTUALLY
TOWARD THE MID-MISSOURI VALLEY. IT SHOULD BE NOTED THAT THE MODEL
INDICATES THE MEAN TROUGH TAKING A NEGATIVE TILT AS IT EMERGES ON
THE PLAINS. COMPLICATING MATTERS...THE EUROPEAN CAMP AND NUMEROUS
GFS ENSEMBLES SUPPORT A SIMILAR TRACK INTO THE CENTRAL PLAINS /AT
LEAST INITIALLY/. SO FOR THE FIRST SUITE OF RUNS PROGGING THIS
SYSTEM...MODEL TO MODEL CONSISTENCY IS SHOWING SOME COHERENCE...BUT
RUN TO RUN CONSISTENCY IS SEVERELY LACKING. CONFIDENCE IN ANY ONE
PARTICULAR SOLUTION IS LOW...ESPECIALLY SINCE ALL LONG TERM GUIDANCE
GENERATES CONVECTION ACROSS THE SOUTHERN PLAINS AND TEXAS ON SUNDAY.
THE GFS SEEMS TO BE KEYING ON THE CONVECTIVE POTENTIAL...GENERATING
AN AREA OF PV DESTRUCTION OVER OUR SOUTH...AND SEVERELY LIMITING THE
QPF POTENTIAL ACROSS MUCH THE CWA. THE GFS HOWEVER DOES EVENTUALLY
GENERATE WRAP AROUND QPF SUNDAY AFTERNOON/EVENING ACROSS OUR SOUTH
AND EAST. THE WRAP AROUND IS IN QUESTION AS THE CONVECTION
/PROJECTED TO BE OVER EASTERN KANSAS/ WOULD ALLOW FOR AN ASSUMED
GREATER EASTWARD WOBBLE OF THE H7 LOW. SO INSTEAD OF THE MODEL
PROJECTED H7 LOW OVER NORTH CENTRAL KANSAS...THE MORE LIKELY
LOCATION WOULD BE EASTERN OR SOUTHEASTERN KANSAS. THE WRAP AROUND
WOULD THUS BE SHUNTED SOUTHEAST AS WELL. THE ECMWF IS
CONCERNING...GENERATING SIGNIFICANT SNOW ACROSS OUR SOUTHERN TIER ON
SUNDAY...BUT AGAIN...THE CONVECTION THAT THE MODEL IS GENERATING
PUTS ANY OF THE QPF ACROSS OUR CWA SEVERELY IN QUESTION. THE CR-INT
PROCEDURE REMAINS PESSIMISTIC IN THE QPF DEPARTMENT FOR SUNDAY AND
BEYOND...WHICH IS FAVORED AT THIS POINT...NO CHANGES WERE MADE TO
THE BLENDED FORECAST. BUT...LAST NIGHT MY FORECAST STATED THE
POTENTIAL WEEKEND STORM WAS LOOKING MORE LIKE A "DUD" FOR THE
CWA...AT THIS TIME I WISH TO RETRACT THOSE WORDS AND STATE THAT THIS
SYSTEM IS CERTAINLY WORTH WATCHING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 556 AM CST TUE DEC 9 2014
FOR THIS MORNING...PATCHY FOG IS LIKELY ALONG THE HIGHWAY 83
CORRIDOR FROM KLBF TO KVTN THROUGH THE LATE MORNING HOURS. AT THE
KVTN TERMINAL...VISBYS MAY DROP TO 1/2SM THROUGH 14Z THIS
MORNING...WITH VISBYS AROUND 3 SM POSSIBLE FROM 14 TO 16Z THIS
MORNING. SKIES WILL GRADUALLY CLEAR DURING THE AFTERNOON
HOURS...WITH MAINLY CLEAR SKIES PERSISTING THROUGH 12Z WEDNESDAY
MORNING. FOR THE KLBF TERMINAL...PATCHY FOG IS POSSIBLE THROUGH
MID MORNING WITH VISBYS AS LOW AS 2SM. SOME SCATTERED HIGH CLOUDS
POSSIBLE DURING THE AFTERNOON HOURS WITH CLEARING THEREAFTER.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...JACOBS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
514 AM CST TUE DEC 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CST TUE DEC 9 2014
SYNOPTIC ANALYSIS OVERNIGHT INDICATES THE UPPER LEVEL TROUGH
CONTINUING TO SHIFT ACROSS THE OHIO RIVER VALLEY WHILE AN UPPER
LEVEL RIDGE HAS BEGUN TO BUILD ACROSS THE ROCKY MOUNTAINS. ALOFT...A
100+ KT JET CAN BE SEEN DIVING SOUTH ACROSS IOWA AND WESTERN
MISSOURI AROUND THE BASE OF THE TROUGH. IN THE MID LEVELS...HEIGHT
RISES SUGGEST THE BUILDING OF THE MID LEVEL RIDGE ACROSS THE
MIDWEST...AND SOME MINIMAL MID LEVEL MOISTURE PRESENT ACROSS THE
PLAINS. AT THE SURFACE...LOW PRESSURE CAN BE SEEN ACROSS THE GREAT
LAKES WHILE A LARGE AREA OF HIGH PRESSURE BEGINS TO SPREAD FROM
MANITOBA STRETCHING SOUTH INTO NEBRASKA. LATEST SATELLITE IMAGERY
SHOWS A LARGE AREA OF STRATUS CIRCULATING UNDER THE UPPER LEVEL
LOW...WITH STRATUS BANDS STRETCHING INTO PORTIONS OF CENTRAL
NEBRASKA. UNDER THESE BANDS...METAR SITES HAVE INDICATED CEILING
HEIGHTS NEAR 1500 FT AND VISIBILITIES AS LOW AS 1/4 MILE AT
VALENTINE.
FOR THE VERY NEAR SHORT TERM...THESE STRATUS BANDS WILL BE OF
CONCERN. SHORT TERM MODELS SUCH AS THE RAP...SREF...AND HRRR ALL
SUGGEST THAT REDUCED VISIBILITIES WILL BE VERY CLOSE TO OUR WESTERN
BORDER...WHILE THE GFS REMAINS DRY. AT THIS TIME...CONTINUED WITH
AREAS OF FOG IN THE FORECAST...BUT WILL CONTINUE TO MONITOR IN CASE
A DENSE FOG ADVISORY IS NEEDED. AS SUCH...AS THE HIGH PRESSURE/RIDGE
AXIS SWINGS THROUGH THE PLAINS...EXPECT WINDS TO SWITCH TO SOUTHERLY
AND HELP CLEAR OUT ANY FOG THAT DOES DEVELOP BY MID TO LATE MORNING.
THE MAIN FOCUS OF THE REST OF THE SHORT TERM PERIOD WILL CENTER ON
THE POSSIBILITY FOR FREEZING DRIZZLE AND FOG OVERNIGHT AND INTO
WEDNESDAY MORNING. AN UPPER LEVEL SHORT WAVE DISTURBANCE WILL
DEVELOP ACROSS THE NORTHERN ROCKIES AND SWING THROUGH THE CENTRAL
PLAINS OVERNIGHT. AT THE SURFACE...LIGHT SOUTH WINDS WILL SURGE LOW
LEVEL MOISTURE NORTHWARD ACROSS MUCH OF THE AREA. THIS COMBINED WITH
LIFT FROM THE UPPER LEVEL DISTURBANCE SHOULD PROMOTE FOG
DEVELOPMENT. HOWEVER...SOUNDINGS INDICATE VERY DRY MID LEVELS AND
BOTH THE NAM AND GFS SOLUTIONS SUGGESTING HIGHER BULK SHEAR VALUES
NEAR 10 KTS...ESPECIALLY ACROSS NORTH CENTRAL KANSAS AND THE STATE
LINE. THEREFORE...IT REMAINS A STRONG POSSIBILITY OF FREEZING
DRIZZLE ACROSS NORTH CENTRAL KANSAS AND SOUTHERN NEBRASKA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CST TUE DEC 9 2014
THE MODELS CONTINUE TO HAVE THE MOISTURE ACROSS THE AREA DURING THE
DAY WEDNESDAY AND EVEN INTO WEDNESDAY NIGHT. EXPECT THE FOG AND
FREEZING DRIZZLE FROM TUESDAY NIGHT TO CONTINUE INTO WEDNESDAY
MORNING. AS TEMPERATURES WARM DURING THE MORNING THE FREEZING
DRIZZLE SHOULD BECOME DRIZZLE. THE PRECIPITATION SHOULD REMAIN
MAINLY IN THE SOUTHEAST PART OF THE FORECAST AREA. WILL CONTINUE
WITH DRIZZLE IN THE SOUTHEAST DURING THE AFTERNOON. THE ONLY MODEL
THAT MOVES THE MOISTURE OFF TO THE EAST IS THE GFS...SO WILL KEEP
THE DRIZZLE INTO THE NIGHT TIME HOURS. IT SHOULD BE IN THE SOUTHEAST
AND SHOULD GRADUALLY END FROM WEST TO EAST DURING THE NIGHT.
THURSDAY AND BEYOND THE MODELS HAVE SEVERAL DIFFERENCES IN TIMING
AND STRENGTH OF THE SYSTEMS AND EVEN SOME RUN TO RUN
INCONSISTENCIES.
THERE IS AN UPPER LEVEL RIDGE THAT WILL MOVE THROUGH THE AREA
THURSDAY AND FRIDAY. EXPECT THE TEMPERATURES TO WARM UP AS THERE
WILL BE PARTLY CLOUDY SKIES AND WARM ADVECTION.
AN UPPER LEVEL SYSTEM IN THE ROCKIES WITH A DEVELOPING SURFACE LOW
ON THE HIGH PLAINS WILL BRING MOISTURE BACK TO THE AREA ON SATURDAY.
THERE WILL BE WARM ADVECTION AND TEMPERATURES WILL BE WARM ON
SATURDAY. THE SURFACE LOW AND COLD FRONT WILL MOVE THROUGH THE
FORECAST AREA SATURDAY NIGHT. THE COOLER AIR STARTS TO MOVE INTO THE
AREA ON SUNDAY AND TEMPERATURES WILL BE A LITTLE COOLER THAN
SATURDAY. THE QUESTION BECOMES PRECIPITATION CHANCES. FORECAST
SOUNDINGS SHOW THAT THERE WILL BE A DRY LAYER AND HAVE KEPT
PRECIPITATION IN THE SOUTHEAST...BUT THAT IS EVEN A LITTLE
QUESTIONABLE. BY SATURDAY NIGHT THE MID LEVELS MOISTEN UP SOME AND
THERE WILL BE A FEW MORE CLOUDS WITH MAYBE SOME RAIN IN THE EAST.
SUNDAY AND SUNDAY NIGHT LOOK LIKE BETTER CHANCES FOR SOME
PRECIPITATION. THIS IS THE FIRST RUN WHERE THE GFS AND THE ECMWF ARE
A LITTLE MORE CONSISTENT WITH THE UPPER LOW IN THE CENTRAL TO
SOUTHERN PLAINS. THE GFS IS FASTER THAN THE ECMWF. WILL KEEP
PRECIPITATION CHANCES FOR SUNDAY AND SUNDAY NIGHT...BRINGING UP THE
QUESTION OF PRECIPITATION TYPE. SUNDAY THE TEMPERATURES SHOULD BE
WARM ENOUGH THAT EXPECT RAIN BUT TEMPERATURES AT 850MB START TO COOL
LATE IN THE AFTERNOON. DURING THE NIGHT THE TEMPERATURES CONTINUE TO
COOL AND THE RAIN SHOULD MIX WITH AND MAYBE CHANGE TO SNOW DURING
THE NIGHT. THE UPPER LOW SHOULD MOVE TO THE EAST AND EXPECT DRY AND
COOL CONDITIONS FOR MONDAY.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 457 AM CST TUE DEC 9 2014
AGAIN FOG AND STRATUS DEVELOPMENT REMAIN THE MAIN CONCERNS FOR THE
TAF PERIOD. LATEST SATELLITE IMAGERY SHOWS A VERY THIN BAND OF
STRATUS SPREADING FROM VALENTINE SOUTHWARD INTO THE LEXINGTON
AREA. THE EDGE OF THIS BAND APPEARS TO BE RIGHT OUTSIDE OF THE
CITY OF KEARNEY. SHORT TERM MODEL SOLUTIONS SUGGEST THAT IT WILL
NOT SPREAD EASTWARD. THUS...DECIDED TO KEEP VFR CONDITIONS AT THE
MOMENT FOR KEAR...ALTHOUGH IT BEARS MONITORING. FOR THE REST OF
THE DAY HIGH PRESSURE WILL ALLOW WINDS TO SHIFT TO SOUTHERLY BY
LATE MORNING. TOWARDS THE END OF THE PERIOD...AN UPPER LEVEL
DISTURBANCE WILL SHIFT PASS THE PLAINS...THIS COMBINED WITH LOW
LEVEL MOISTURE...LIGHT WINDS AT THE SURFACE...FOG DEVELOPMENT IS
POSSIBLE AGAIN TOMORROW MORNING. SOME MODELS ARE ALSO LEANING
TOWARDS FREEZING DRIZZLE...ALTHOUGH MORE LIKELY SOUTH OF
INTERSTATE 80. WILL NEED TO CONTINUE WATCHING FUTURE MODEL RUNS
FOR NORTHWARD EXPANSION OF FREEZING DRIZZLE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...SALTZMAN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
358 AM CST TUE DEC 9 2014
.SYNOPSIS...
ISSUED AT 358 AM CST TUE DEC 9 2014
H5 ANALYSIS FROM EARLIER THIS EVENING HAD A DECENT UPPER LEVEL
DISTURBANCE OVER NRN ILLINOIS WITH A TROUGH EXTENDING SWD TO THE
FLORIDA PANHANDLE. FURTHER WEST...A BROAD RIDGE EXTENDED FROM THE
INTERMOUNTAIN WEST NORTH INTO THE YUKON OF CANADA. WITHIN THIS
RIDGE...A DISTURBANCE WAS NOTED OVER WESTERN MONTANA. CURRENT WV
IMAGERY AS OF 2 AM CST HAS THIS FEATURE NOW OVER EASTERN PORTIONS
OF MT. AT THE SURFACE...AN ELONGATED AREA OF HIGH PRESSURE
EXTENDED ACROSS THE EASTERN DAKOTAS INTO EASTERN NEBRASKA. FURTHER
WEST...A TROUGH OF LOW PRESSURE WAS PRESENT OVER EASTERN WYOMING
INTO NORTHERN COLORADO. AN AREA OF STRATUS AND FOG HAS DEVELOPED
ON THE WESTERN PERIPHERY OF THE HIGH OVERNIGHT...AND THIS AREA OF
CLOUDS AND FOG EXTENDED FROM NORTH CENTRAL NEBRASKA INTO CENTRAL
AND PORTIONS OF SWRN NEBRASKA. THE FOG WAS PRIMARILY ALONG THE
WESTERN EDGE OF THE STRATUS/LOW CLOUDS AND ROUGHLY EXTENDED FROM
VALENTINE TO AINSWORTH...SWD TO THEDFORD...NORTH PLATTE AND BROKEN
BOW. FURTHER WEST...SOME HIGH CLOUDS WERE MOVING INTO THE NEBRASKA
PANHANDLE AND FAR WESTERN PORTIONS OF THE FORECAST AREA ATTM.
UNDER MOSTLY CLOUDY SKIES...TEMPERATURES AS OF 3 AM CST...RANGED
FROM 15 AT NORTH PLATTE TO 25 AT BROKEN BOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST TUE DEC 9 2014
TODAY AND TONIGHT...THE FORECAST CHALLENGES OVER THE NEXT 24
HOURS...ARE TEMPERATURES TODAY...AS WELL AS FOG POTENTIAL THIS
MORNING...AS WELL AS TONIGHT. FOR TODAY...AS MENTIONED ABOVE...FOG
HAS DEVELOPED ALONG THE HIGHWAY 83 CORRIDOR...AS WELL AS ALONG A
LINE FROM AINSWORTH TO BROKEN BOW. ATTM...THE LATEST HI RES RUC
SOLN HAS THIS AREA OF FOG EXPANDING SLIGHTLY TO THE SOUTHWEST
TOWARD DAYBREAK. ONE WILDCARD IN THE DEGREE OF WESTWARD
DEVELOPMENT OF FOG...IS THE POTENTIAL IMPACT OF HIGH LEVEL
CLOUDINESS MOVING IN FROM THE WEST. ATTM...FOG VISBYS HAVE BEEN
GENERALLY IN THE 1 TO 5 MILE RANGE...SO WILL KEEP FOG MENTION AS
PATCHY THIS MORNING. BASED ON THE HRRR SOLN...FOG SHOULD BEGIN TO
DISSIPATE DURING THE MID TO LATE MORNING TIME FRAME...AND HAVE
EXTENDED THIS MENTION OF FOG INTO THE LATE MORNING HOURS GIVEN
THIS MODEL TREND. HIGH PRESSURE WILL BEGIN TO TRACK EAST LATER
TODAY INCREASING SRLY WINDS DURING THE AFTERNOON HOURS. FOR
LOCATIONS GENERALLY WEST OF HIGHWAY 61...THE WIND DIRECTION WILL
TAKE ON A WESTERLY COMPONENT...RESULTING IN SOME LIMITED DOWNSLOPE
AND WARMER HIGHS IN THE LOWER 50S. FURTHER EAST...THE COMBINATION
OF CLOUDS...SOUTHERLY AND SOUTHEASTERLY WINDS ON THE BACK SIDE OF
THE EXITING HIGH...WILL LIMIT HIGHS IN THE UPPER 30S IN THE FAR
NORTHEAST...TO THE 40S ALONG THE HIGHWAY 83 CORRIDOR. THE LATEST
MAV GUIDANCE HAS TRENDED COLDER FOR HIGHS OVER THE PAST 3
RUNS...AND HAS COME INTO BETTER AGREEMENT WITH THE COLDER MET
GUIDANCE. WITH THIS IN MIND...TRENDED HIGHS TDY SOME 2 TO 4
DEGREES COLDER THAN THE INHERITED FCST. FOR TONIGHT...LIGHT SRLY
WINDS WILL CONTINUE...PARTICULARLY IN THE EASTERN CWA. THE LATEST
NAM SOLN IS INDICATING NEAR SATURATION IN THE BOUNDARY LAYER
OVERNIGHT TONIGHT...ROUGHLY EAST OF A LINE FROM CURTIS...TO
ONEILL. INHERITED FCST HAD A MENTION OF PATCHY FOG OVERNIGHT IN
THESE AREAS AND IT WILL BE CONTINUED WITH THE CURRENT FCST
PACKAGE. OVERNIGHT LOWS WILL BE IN THE LOWER 20S...WITH SOME UPPER
TEENS IN THE PLATTE RIVER VALLEY GIVEN THE EXPECTED LIGHT WINDS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CST TUE DEC 9 2014
12Z WEDNESDAY AND BEYOND...MODELS REMAIN IN GOOD AGREEMENT THAT
AMPLIFIED UPPER RIDGING OVER THE CENTRAL CONUS WILL EVENTUALLY BREAK
DOWN/FORCED EAST AS A LONG WAVE TROUGH DIGS INTO THE WESTERN STATES
AND EVENTUALLY THE PLAINS. TEMPERATURES UNDER THE RIDGE WILL REMAIN
ABOVE AVERAGE...AND SHOULD WARM BY SEVERAL DEGREES EACH DAY. HIGHS
BY FRIDAY ARE ANTICIPATED TO REACH INTO THE 50S TO LOWER 60S FOR
MOST AREAS...POSSIBLY WARMER IF GREATER MIXING OCCURS.
SOUTHERLY WINDS WILL HELP INCREASE LOWER LEVEL MOISTURE WHICH COULD
PROVIDE FOR PATCHY FOG EACH MORNING...WEDNESDAY THROUGH SATURDAY.
THE DETERMINISTIC SOLUTIONS GENERATE LIGHT DZ/QPF ACROSS PORTIONS OF
OUR EAST THURSDAY...FRIDAY...AND SATURDAY...BUT THE MOISTURE
PROFILES ONLY FAVOR STRATUS AND/OR FOG AS THE DEPTH OF THE RETURN IS
RATHER SHALLOW.
CONCERNING THIS WEEKEND AND A POTENTIAL SYSTEM...WHAT A DIFFERENCE A
DAY MAKES. IN 24 HOURS THE GFS SOLUTION HAS TRENDED NORTH WITH THE
TRACK OF THIS WEEKENDS CLOSED H5 LOW BY HUNDREDS OF MILES. THE
MODEL GENERATED TRACK OF THE LOW YESTERDAY FAVORED THE BIG BEND
OF TEXAS ON SUNDAY...THEREAFTER TRACKING THE LOW OVER HEART OF TEXAS
THROUGH EARLY NEXT WEEK. TONIGHT...THE GFS IS FAVORING A SOLUTION
WHICH CLOSES OFF A LOW OVER NORTHERN NEW MEXICO...THEN TRACKING THE
LOW ACROSS THE PANHANDLES OF TEXAS AND OKLAHOMA...AND EVENTUALLY
TOWARD THE MID-MISSOURI VALLEY. IT SHOULD BE NOTED THAT THE MODEL
INDICATES THE MEAN TROUGH TAKING A NEGATIVE TILT AS IT EMERGES ON
THE PLAINS. COMPLICATING MATTERS...THE EUROPEAN CAMP AND NUMEROUS
GFS ENSEMBLES SUPPORT A SIMILAR TRACK INTO THE CENTRAL PLAINS /AT
LEAST INITIALLY/. SO FOR THE FIRST SUITE OF RUNS PROGGING THIS
SYSTEM...MODEL TO MODEL CONSISTENCY IS SHOWING SOME COHERENCE...BUT
RUN TO RUN CONSISTENCY IS SEVERELY LACKING. CONFIDENCE IN ANY ONE
PARTICULAR SOLUTION IS LOW...ESPECIALLY SINCE ALL LONG TERM GUIDANCE
GENERATES CONVECTION ACROSS THE SOUTHERN PLAINS AND TEXAS ON SUNDAY.
THE GFS SEEMS TO BE KEYING ON THE CONVECTIVE POTENTIAL...GENERATING
AN AREA OF PV DESTRUCTION OVER OUR SOUTH...AND SEVERELY LIMITING THE
QPF POTENTIAL ACROSS MUCH THE CWA. THE GFS HOWEVER DOES EVENTUALLY
GENERATE WRAP AROUND QPF SUNDAY AFTERNOON/EVENING ACROSS OUR SOUTH
AND EAST. THE WRAP AROUND IS IN QUESTION AS THE CONVECTION
/PROJECTED TO BE OVER EASTERN KANSAS/ WOULD ALLOW FOR AN ASSUMED
GREATER EASTWARD WOBBLE OF THE H7 LOW. SO INSTEAD OF THE MODEL
PROJECTED H7 LOW OVER NORTH CENTRAL KANSAS...THE MORE LIKELY
LOCATION WOULD BE EASTERN OR SOUTHEASTERN KANSAS. THE WRAP AROUND
WOULD THUS BE SHUNTED SOUTHEAST AS WELL. THE ECMWF IS
CONCERNING...GENERATING SIGNIFICANT SNOW ACROSS OUR SOUTHERN TIER ON
SUNDAY...BUT AGAIN...THE CONVECTION THAT THE MODEL IS GENERATING
PUTS ANY OF THE QPF ACROSS OUR CWA SEVERELY IN QUESTION. THE CR-INT
PROCEDURE REMAINS PESSIMISTIC IN THE QPF DEPARTMENT FOR SUNDAY AND
BEYOND...WHICH IS FAVORED AT THIS POINT...NO CHANGES WERE MADE TO
THE BLENDED FORECAST. BUT...LAST NIGHT MY FORECAST STATED THE
POTENTIAL WEEKEND STORM WAS LOOKING MORE LIKE A "DUD" FOR THE
CWA...AT THIS TIME I WISH TO RETRACT THOSE WORDS AND STATE THAT THIS
SYSTEM IS CERTAINLY WORTH WATCHING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 618 PM CST MON DEC 8 2014
A BAND OF STRATUS ALONG THE BACKDOOR COLD FRONT WILL MOVE
SOUTHWEST INTO NORTH CENTRAL NEBRASKA THIS EVENING WITH CIGS
AROUND BKN020. THROUGH THE EARLY MORNING HOURS SOME FOG WITH MVFR
VISIBILITIES IS EXPECTED TO DEVELOP OVER SOUTHWEST NEBRASKA. THIS
FOG WILL BURN OFF EARLY SOME IFR CEILINGS ARE POSSIBLE BUT
SIGNATURE NOT REAL STRONG SO HAVE LEFT OUT OF NORTH PLATTE TAF FOR
NOW. WINDS BECOMING LIGHT AND VARIABLE OVER NIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...JACOBS
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
337 AM CST TUE DEC 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CST TUE DEC 9 2014
SYNOPTIC ANALYSIS OVERNIGHT INDICATES THE UPPER LEVEL TROUGH
CONTINUING TO SHIFT ACROSS THE OHIO RIVER VALLEY WHILE AN UPPER
LEVEL RIDGE HAS BEGUN TO BUILD ACROSS THE ROCKY MOUNTAINS. ALOFT...A
100+ KT JET CAN BE SEEN DIVING SOUTH ACROSS IOWA AND WESTERN
MISSOURI AROUND THE BASE OF THE TROUGH. IN THE MID LEVELS...HEIGHT
RISES SUGGEST THE BUILDING OF THE MID LEVEL RIDGE ACROSS THE
MIDWEST...AND SOME MINIMAL MID LEVEL MOISTURE PRESENT ACROSS THE
PLAINS. AT THE SURFACE...LOW PRESSURE CAN BE SEEN ACROSS THE GREAT
LAKES WHILE A LARGE AREA OF HIGH PRESSURE BEGINS TO SPREAD FROM
MANITOBA STRETCHING SOUTH INTO NEBRASKA. LATEST SATELLITE IMAGERY
SHOWS A LARGE AREA OF STRATUS CIRCULATING UNDER THE UPPER LEVEL
LOW...WITH STRATUS BANDS STETCHING INTO PORTIONS OF CENTRAL
NEBRASKA. UNDER THESE BANDS...METAR SITES HAVE INDICATED CEILING
HEIGHTS NEAR 1500 FT AND VISIBILITIES AS LOW AS 1/4 MILE AT
VALENTINE.
FOR THE VERY NEAR SHORT TERM...THESE STRATUS BANDS WILL BE OF
CONCERN. SHORT TERM MODELS SUCH AS THE RAP...SREF...AND HRRR ALL
SUGGEST THAT REDUCED VISIBILITIES WILL BE VERY CLOSE TO OUR WESTERN
BORDER...WHILE THE GFS REMAINS DRY. AT THIS TIME...CONTINUED WITH
AREAS OF FOG IN THE FORECAST...BUT WILL CONTINUE TO MONITOR IN CASE
A DENSE FOG ADVISORY IS NEEDED. AS SUCH...AS THE HIGH PRESSURE/RIDGE
AXIS SWINGS THROUGH THE PLAINS...EXPECT WINDS TO SWITCH TO SOUTHERLY
AND HELP CLEAR OUT ANY FOG THAT DOES DEVELOP BY MID TO LATE MORNING.
THE MAIN FOCUS OF THE REST OF THE SHORT TERM PERIOD WILL CENTER ON
THE POSSIBILITY FOR FREEZING DRIZZLE AND FOG OVERNIGHT AND INTO
WEDNESDAY MORNING. AN UPPER LEVEL SHORT WAVE DISTURBANCE WILL
DEVELOP ACROSS THE NORTHERN ROCKIES AND SWING THROUGH THE CENTRAL
PLAINS OVERNIGHT. AT THE SURFACE...LIGHT SOUTH WINDS WILL SURGE LOW
LEVEL MOISTURE NORTHWARD ACROSS MUCH OF THE AREA. THIS COMBINED WITH
LIFT FROM THE UPPER LEVEL DISTURBANCE SHOULD PROMOTE FOG
DEVELOPMENT. HOWEVER...SOUNDINGS INDICATE VERY DRY MID LEVELS AND
BOTH THE NAM AND GFS SOLUTIONS SUGGESTING HIGHER BULK SHEAR VALUES
NEAR 10 KTS...ESPECIALLY ACROSS NORTH CENTRAL KANSAS AND THE STATE
LINE. THEREFORE...IT REMAINS A STRONG POSSIBILITY OF FREEZING
DRIZZLE ACROSS NORTH CENTRAL KANSAS AND SOUTHERN NEBRASKA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CST TUE DEC 9 2014
THE MODELS CONTINUE TO HAVE THE MOISTURE ACROSS THE AREA DURING THE
DAY WEDNESDAY AND EVEN INTO WEDNESDAY NIGHT. EXPECT THE FOG AND
FREEZING DRIZZLE FROM TUESDAY NIGHT TO CONTINUE INTO WEDNESDAY
MORNING. AS TEMPERATURES WARM DURING THE MORNING THE FREEZING
DRIZZLE SHOULD BECOME DRIZZLE. THE PRECIPITATION SHOULD REMAIN
MAINLY IN THE SOUTHEAST PART OF THE FORECAST AREA. WILL CONTINUE
WITH DRIZZLE IN THE SOUTHEAST DURING THE AFTERNOON. THE ONLY MODEL
THAT MOVES THE MOISTURE OFF TO THE EAST IS THE GFS...SO WILL KEEP
THE DRIZZLE INTO THE NIGHT TIME HOURS. IT SHOULD BE IN THE SOUTHEAST
AND SHOULD GRADUALLY END FROM WEST TO EAST DURING THE NIGHT.
THURSDAY AND BEYOND THE MODELS HAVE SEVERAL DIFFERENCES IN TIMING
AND STRENGTH OF THE SYSTEMS AND EVEN SOME RUN TO RUN
INCONSISTENCIES.
THERE IS AN UPPER LEVEL RIDGE THAT WILL MOVE THROUGH THE AREA
THURSDAY AND FRIDAY. EXPECT THE TEMPERATURES TO WARM UP AS THERE
WILL BE PARTLY CLOUDY SKIES AND WARM ADVECTION.
AN UPPER LEVEL SYSTEM IN THE ROCKIES WITH A DEVELOPING SURFACE LOW
ON THE HIGH PLAINS WILL BRING MOISTURE BACK TO THE AREA ON SATURDAY.
THERE WILL BE WARM ADVECTION AND TEMPERATURES WILL BE WARM ON
SATURDAY. THE SURFACE LOW AND COLD FRONT WILL MOVE THROUGH THE
FORECAST AREA SATURDAY NIGHT. THE COOLER AIR STARTS TO MOVE INTO THE
AREA ON SUNDAY AND TEMPERATURES WILL BE A LITTLE COOLER THAN
SATURDAY. THE QUESTION BECOMES PRECIPITATION CHANCES. FORECAST
SOUNDINGS SHOW THAT THERE WILL BE A DRY LAYER AND HAVE KEPT
PRECIPITATION IN THE SOUTHEAST...BUT THAT IS EVEN A LITTLE
QUESTIONABLE. BY SATURDAY NIGHT THE MID LEVELS MOISTEN UP SOME AND
THERE WILL BE A FEW MORE CLOUDS WITH MAYBE SOME RAIN IN THE EAST.
SUNDAY AND SUNDAY NIGHT LOOK LIKE BETTER CHANCES FOR SOME
PRECIPITATION. THIS IS THE FIRST RUN WHERE THE GFS AND THE ECMWF ARE
A LITTLE MORE CONSISTENT WITH THE UPPER LOW IN THE CENTRAL TO
SOUTHERN PLAINS. THE GFS IS FASTER THAN THE ECMWF. WILL KEEP
PRECIPITATION CHANCES FOR SUNDAY AND SUNDAY NIGHT...BRINGING UP THE
QUESTION OF PRECIPITATION TYPE. SUNDAY THE TEMPERATURES SHOULD BE
WARM ENOUGH THAT EXPECT RAIN BUT TEMPERATURES AT 850MB START TO COOL
LATE IN THE AFTERNOON. DURING THE NIGHT THE TEMPERATURES CONTINUE TO
COOL AND THE RAIN SHOULD MIX WITH AND MAYBE CHANGE TO SNOW DURING
THE NIGHT. THE UPPER LOW SHOULD MOVE TO THE EAST AND EXPECT DRY AND
COOL CONDITIONS FOR MONDAY.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1114 PM CST MON DEC 8 2014
THE MAIN CONCERNS FOR BOTH THE KGRI AND KEAR TAF SITES DURING THE
PERIOD WILL CENTER AROUND A DEVELOPING STRATUS DECK OFF TO THE
NORTHEAST AS WELL AS SUBSEQUENT FOG AND STRATUS DEVELOPMENT DURING
THE EARLY MORNING HOURS TODAY. AS AN UPPER LEVEL LOW DEPARTS THE
GREAT LAKES REGION...A THIN STRATUS BAND HAS BEGUN TO SHIFT
SOUTHWEST ACROSS NEBRASKA. ALTHOUGH NOT A SOLID BAND...SITES UNDER
THE STRATUS ARE CURRENTLY OVC AT 1800 FT. EXPECT SITES TO WAIVER
AS THIS STRATUS DECK PASSES THUS WENT WITH A TEMPO GROUP. TOWARDS
THE MORNING HOURS...SURFACE HIGH PRESSURE WILL BUILD IN ACROSS THE
REGION ALLOWING FOR CALM WINDS. THIS COMBINED WITH MOISTURE AT THE
SURFACE AND RADIATIONAL COOLING WILL LIKELY PROMOTE FURTHER
STRATUS DEVELOPMENT AS WELL AS FOG POTENTIAL. CURRENT THINKING IS
THAT REDUCED VISIBILITIES WILL BE WORSE FURTHER WEST. WINDS WILL
SWITCH TO THE SOUTH AFTER THE PASSAGE OF THE HIGH PRESSURE SYSTEM
BY LATE MORNING ALLOWING FOR CLEARING OF ANY FOG AND STRATUS
DECK.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...SALTZMAN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1047 PM CST MON DEC 8 2014
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CST MON DEC 8 2014
THE PRIMARY FORECAST CONCERNS FOR TONIGHT AND TUESDAY ARE CLOUD
COVER AND RESULTING TEMPERATURES. ATTENTION TURNS MORE TOWARD THE
POTENTIAL FOR LOW CLOUDS/FOG/DRIZZLE WEDNESDAY INTO THURSDAY.
LARGE SCALE 500 MB PATTERN AT 12Z HAD THE FOLLOWING MAIN FEATURES.
A TROUGH WAS LOCATED TO OUR EAST/NORTHEAST...A RIDGE STRETCHED
FROM THE SOUTHERN ROCKIES INTO ALASKA AND A BROAD TROUGH WAS OUT
OVER THE PACIFIC. A CLOSED LOW SHOULD DEVELOP OUT OF THE TROUGH TO
OUR EAST IN THE EAST CENTRAL PART OF THE UNITED STATES BY TUESDAY
NIGHT. THAT FEATURE WILL THEN LIKELY WOBBLE INTO THE NORTHEAST
STATES INTO SATURDAY. IN OUR AREA...GENERAL RIDGING OCCURS IN THE
MID LEVELS BUT THERE WILL BE SOME SHORTWAVE ENERGY TRACKING EAST
THROUGH THE MEAN RIDGE...MAKING THE PATTERN A BIT MESSY. THE TROUGH
IN THE PACIFIC WILL BE PROGRESSIVE..AND BRING VERY WET WEATHER TO
MUCH OF THE WEST COAST THIS WEEK.
TONIGHT...CLOUD COVER IS PROBLEMATIC. LOW CLOUDS CURRENTLY IN A BAND
FROM NORTHERN IOWA ACROSS PARTS OF SOUTH DAKOTA AND INTO WESTERN
NORTH DAKOTA. THESE MAY TRY TO SINK SOUTHWARD INTO OUR AREA. THE MOST
RECENT RAP AND HRRR MODEL RUNS TEND TO DISSIPATE THIS
CLOUDINESS...BUT 12Z HIGH RESOLUTION NAM AND GFS DID BRING THE LOW
LEVEL MOISTURE SOUTHWARD. EVENING SHIFT WILL NEED TO MONITOR. A
COLD FRONT WAS ALREADY TRACKING SOUTHWARD INTO NORTHEAST NEBRASKA
AS OF EARLY THIS AFTERNOON AND WILL CONTINUE TO PUSH SOUTHWARD
THIS EVENING. COLD HIGH PRESSURE SHOULD BUILD IN BEHIND THE FRONT
FOR TONIGHT. WE EXPECT LOWS TO RANGE FROM THE UPPER TEENS NORTH TO
THE LOWER 20S SOUTH.
TUESDAY SHOULD BE COLDER THAN TODAY...WITH ONLY POOR TO FAIR MIXING.
NORTHEAST WINDS EARLY TURNING TO THE EAST OR SOUTHEAST DURING THE
DAY...AND HIGHS SHOULD TOP OUT MAINLY IN THE 30S. AS LOW LEVEL
SOUTHERLY FLOW STRENGTHENS...WE WILL HAVE TO MONITOR FOR DEVELOPMENT
OF LOW CLOUDS AND POSSIBLE DRIZZLE. THE BEST CHANCE FOR LIGHT RAIN
STAYS TO OUR SOUTH IN KANSAS FOR WEDNESDAY/WEDNESDAY NIGHT...BUT
AFTER COORDINATION WITH BORDERING OFFICES...ADDED SOME DRIZZLE INTO
OUR SOUTHERN COUNTIES FOR WEDNESDAY. THIS COULD BE FREEZING DRIZZLE
EARLY WEDNESDAY UNTIL TEMPERATURES RISE ABOVE 32 F. KEPT SOME
MENTION OF DRIZZLE INTO WEDNESDAY NIGHT. BEST LIFT MOVES INTO
SOUTHERN IOWA/NORTHERN MISSOURI FOR THURSDAY SO DID NOT INCLUDE
MENTION OF DRIZZLE IN THAT PERIOD. HIGHS THURSDAY SHOULD REACH
INTO THE 40S...POSSIBLY WARMER IF CLOUD COVER IS LESS THAN EXPECTED.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 320 PM CST MON DEC 8 2014
PATTERN IS A BIT MORE ACTIVE IN THIS PERIOD. 500 MB RIDGE WILL BE IN
PLACE FROM NEW MEXICO ACROSS OUR AREA AND INTO ONTARIO AT 12Z FRIDAY
...WITH MODELS IN GOOD AGREEMENT WITH STRENGTH AND LOCATION OF A
STRONG TROUGH ALONG THE WEST COAST. THE PATTERN OF LOW CLOUDS AND
DRIZZLE MAY CONTINUE INTO FRIDAY. WENT SOMEWHAT CONSERVATIVE FOR
HIGHS FRIDAY AND SATURDAY...MAINLY LOWER/MID 50S FRIDAY AND MID/
UPPER 50S SATURDAY.
INCREASING SOUTHWEST FLOW WILL TRANSPORT MOISTURE AND EVEN SOME
INSTABILITY INTO THE CENTRAL PLAINS FOR THE WEEKEND. HAVE SOME
MENTION OF SHOWERS FOR AT LEAST PARTS OF THE AREA FROM SATURDAY INTO
MONDAY...WITH HIGHEST CHANCES FOR SOUTHEAST NEBRASKA AND SOUTHWEST
IOWA. ONE MAIN MID LEVEL LOW TRACKS ALONG THE CANADIAN BORDER WHILE
THE OTHER MOVES EAST ACROSS NORTH TEXAS. THAT SHOULD KEEP THE
HEAVIEST PCPN AMOUNTS OUT OF OUR AREA.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1044 PM CST MON DEC 8 2014
BAND OF MVFR STRATUS IS THINNING AND DISSIPATING ON THE WESTERN
EDGE AND SHOULD BE CLEAR OF TAF SITES BY 06Z. HELD ONTO SCATTERED
MVFR CEILINGS AS BAND DISSIPATES...WITH NORTH WINDS AROUND
10-15KT EARLY IN THE PERIOD AND SLOWLY DECREASING THROUGH THE
NIGHT. FOR THE REST OF THE TAF PERIOD...SCATTERED CEILINGS AT OR
ABOVE 15KFT ARE POSSIBLE...WITH WINDS DROPPING TO LIGHT AND
VARIABLE AS HIGH PRESSURE MOVES ACROSS THE REGION.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...MAYES
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
335 PM EST TUE DEC 9 2014
.SYNOPSIS...
A VERY SLOWLY MOVING NOR EASTER WILL HAVE A LARGE IMPACT ON THE
REGION. MIXED PRECIPITATION WILL BEGIN TO MIX WITH AND CHANGE TO
SNOW TONIGHT. LIGHT SNOW ACCUMULATIONS ARE EXPECTED AREAWIDE THROUGH
THURSDAY MORNING...AS WELL AS SOME LIGHT ICE ACCUMULATIONS MAINLY AT
HIGHER ELEVATIONS.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
1 PM UPDATE...
SFC LOPRES HAS DROPPED DOWN TO NR 1000MB AS IT SPINS OFF THE JERSEY
SHORE. MODERATE TO HVY PCPN IS ONGOING ACRS ERN HALF OF CWA AS
EXPECTED BUT THERMAL PROFILES ARE TOO WARM FOR SNOW. SOME HIGHER
ELEVATION SITES ARE STILL RIGHT AT OR BLO FRZG AS OF 17Z WITH -FZRA
FALLING AT THESE LOCATIONS AND HEARING ABOUT NUMEROUS MOTOR VEHICLE
ACCIDENTS.
PCPN HAS ESSENTIALLY HIT A BRICK WALL AT THE I-81 CORRIDOR AND NOT
EXPECTING THIS TO MV MUCH FURTHER EAST THAN WHERE IT CURRENTLY IS
NOW UNTIL AFT 00Z. DEFORMATION BAND THAT THE MODELS WERE INSISTENT
WUD ROTATE WEST THRU THE EVNG HRS IS NOW LOOKING TO BE A FRACTURED
BAND OF MIXED PCPN.
H9 TEMPS PER LATEST RUC MODEL INDICATING BLYR TEMPS RMNG ISOTHERMAL
THRU 21Z THIS AFTN AND VRY SLOWLY DROPPING BYND THIS TIME. EXPECT A
MIXED BAG THRU BULK OF THE OVRNGT FOR SXNS EAST OF I-81 WITH CLD AIR
BEING PULLED IN FM THE WEST. ANOTHER WV FCST TO MV THRU NRN ZONES
AFT 06Z TONIGHT AND WITH MOISTURE FM LK ADDED IN EXPECT SVRL INCHES
OF SNOW TO FALL ACRS THE FINGER LKS BY 12Z. STORM TOTAL SNOWFALL
THRU THE OVRNGT IS NOW LOOKING TO BE MEAGER WITH A GNRL INCH OR TWO
ACRS THE BULK OF THE AREA AND POSSIBLY 2-4 INCHES IN HIGHER
ELEVATIONS OF SUSQUEHANNA REGION.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
315 PM UPDATE...
MOISTURE WL CONTINUE TO WRAP-ARND THE NOR`EASTER THRU THE SHORT
TERM. DEFORMATION BAND FINALLY GETTING ITS ACT TOGETHER CURRENTLY
AND WL ROTATE INTO THE FINGER LKS BY MORNING. ADDED MOISTURE OFF
OF THE LKS WL LKLY BRING 3-6 INCHES OF SNOW ACRS FINGER LKS AND
SUSQUEHANNA REGION DRG THE DAY WED THO AMNTS MAY BE SLIGHTLY
HIGHER, THUS HV OPTED TO KEEP WARNINGS GOING FOR CNTRL NY.
SYSTEM WL BCM VERTICALLY STACKED DRG THE DAY TOMORROW AND WITH NW
FLOW MVG DOWN ACRS THE LKS EXPECT SNOW TO CONTINUE ON WEDNESDAY.
ONLY QUESTION WL BE IS IF DRY SLOT WL MV IN FM THE EAST AND
DENDRITE ZONE WL LOSE MOISTURE DRG THE AFTN HRS BUT WL ALLOW
LATER SHIFTS DECIDE ON DROPPING HEADLINES EARLY.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
PERIOD BEGINS WITH PERSISTENT UPPER LOW WOBBLING AROUND OVER
EASTERN NEW YORK AND SOUTHERN NEW ENGLAND. THIS WILL PUT OUR AREA
IN A FAVORABLE LOCATION FOR PERIODS OF SNOW WRAPPING AROUND THE
UPPER LOW. HAVE GONE WITH LIKELY POPS FOR THURSDAY ACROSS NY AND
FAR NORTHERN PA WITH HIGH CHANCE DONE AROUND I-80 FOR SNOW
SHOWERS. 850 MB TEMPERATURES ARE FORECAST TO BE AROUND -6 TO -8 WITH
WARM ADVECTION FROM THE NORTH-NORTHEAST. THIS SHOULD BE COLD
ENOUGH FOR SOME LAKE ENHANCEMENT IN THE NNW FLOW. THIS PATTERN IS
USUALLY FAVORABLE FOR WIDESPREAD LIGHT TO MODERATE SNOWFALL ACROSS
OUR AREA ESPECIALLY ACROSS NY STATE WITH MANY AREAS PROBABLY STILL
GETTING ANOTHER COUPLE OF INCHES OF SNOW.
UPPER LOW REMAINS OVER NEW ENGLAND INTO SATURDAY. AS A RESULT
SCATTERED SNOW SHWOERS REMAIN IN THE FORECAST INTO SATURDAY ALONG
WITH BELOW NORMAL TEMPERATURES. COMPLETELY DRY WEATHER SHOULD
RETURN BY SUNDAY AND MONDAY ALONG WITH MODERATING TEMPERATURES.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
RAIN WITH POCKETS OF FREEZING RAIN WILL CHANGE TO SNOW AND SNOW
SHOWERS TONIGHT AS LOW PRESSURE REMAINS NEARLY STATIONARY ALONG
THE EAST COAST. SNOW SHOWERS WILL PERSIST THROUGH WEDNESDAY. CIGS
WILL BE MOSTLY MVFR WITH AREAS OF IFR ESPECIALLY ON HILL TOP
AIRPORTS SUCH AS ITH AND BGM. VSBYS WILL FALL TO IFR AS
PRECIPITATION CHANGES TO SNOW AND SNOW SHOWERS TONIGHT. WINDS WILL
BE LIGHT AND VARIABLE BECOMING NORTH AT 5 TO 10 KTS THIS AFTERNOON
THEN NORTHWEST AT 10 TO 15 KTS TONIGHT AND WEDNESDAY WITH GUSTS OF
20 TO 25 KTS WEDNESDAY.
OUTLOOK...
TUE NGT THROUGH WED...MVFR/IFR IN SNOW OR BLSN. NEAR AIRPORT MINS AT
TIMES IN BANDS OF HEAVY SNOW TUE NGT-EARLY WED.
THU/FRI...RESTRICTIONS POSSIBLE IN SHSN. BETTER CHC IN NY.
SAT...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR PAZ039-040.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR PAZ038-043-
044-047-048-072.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ009-
015>018-023-025-036-037-044>046-055>057.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR NYZ022-024-
062.
&&
$$
SYNOPSIS...PVF
NEAR TERM...PVF
SHORT TERM...PVF
LONG TERM...DJP/MSE
AVIATION...DJP/MSE
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
316 PM EST TUE DEC 9 2014
.SYNOPSIS...
A VERY SLOWLY MOVING NOR EASTER WILL HAVE A LARGE IMPACT ON THE
REGION. MIXED PRECIPITATION WILL BEGIN TO MIX WITH AND CHANGE TO
SNOW TONIGHT. LIGHT SNOW ACCUMULATIONS ARE EXPECTED AREAWIDE THROUGH
THURSDAY MORNING...AS WELL AS SOME LIGHT ICE ACCUMULATIONS MAINLY AT
HIGHER ELEVATIONS.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
1 PM UPDATE...
SFC LOPRES HAS DROPPED DOWN TO NR 1000MB AS IT SPINS OFF THE JERSEY
SHORE. MODERATE TO HVY PCPN IS ONGOING ACRS ERN HALF OF CWA AS
EXPECTED BUT THERMAL PROFILES ARE TOO WARM FOR SNOW. SOME HIGHER
ELEVATION SITES ARE STILL RIGHT AT OR BLO FRZG AS OF 17Z WITH -FZRA
FALLING AT THESE LOCATIONS AND HEARING ABOUT NUMEROUS MOTOR VEHICLE
ACCIDENTS.
PCPN HAS ESSENTIALLY HIT A BRICK WALL AT THE I-81 CORRIDOR AND NOT
EXPECTING THIS TO MV MUCH FURTHER EAST THAN WHERE IT CURRENTLY IS
NOW UNTIL AFT 00Z. DEFORMATION BAND THAT THE MODELS WERE INSISTENT
WUD ROTATE WEST THRU THE EVNG HRS IS NOW LOOKING TO BE A FRACTURED
BAND OF MIXED PCPN.
H9 TEMPS PER LATEST RUC MODEL INDICATING BLYR TEMPS RMNG ISOTHERMAL
THRU 21Z THIS AFTN AND VRY SLOWLY DROPPING BYND THIS TIME. EXPECT A
MIXED BAG THRU BULK OF THE OVRNGT FOR SXNS EAST OF I-81 WITH CLD AIR
BEING PULLED IN FM THE WEST. ANOTHER WV FCST TO MV THRU NRN ZONES
AFT 06Z TONIGHT AND WITH MOISTURE FM LK ADDED IN EXPECT SVRL INCHES
OF SNOW TO FALL ACRS THE FINGER LKS BY 12Z. STORM TOTAL SNOWFALL
THRU THE OVRNGT IS NOW LOOKING TO BE MEAGER WITH A GNRL INCH OR TWO
ACRS THE BULK OF THE AREA AND POSSIBLY 2-4 INCHES IN HIGHER
ELEVATIONS OF SUSQUEHANNA REGION.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
315 PM UPDATE...
MOISTURE WL CONTINUE TO WRAP-ARND THE NOR`EASTER THRU THE SHORT
TERM. DEFORMATION BAND FINALLY GETTING ITS ACT TOGETHER CURRENTLY
AND WL ROTATE INTO THE FINGER LKS BY MORNING. ADDED MOISTURE OFF
OF THE LKS WL LKLY BRING 3-6 INCHES OF SNOW ACRS FINGER LKS AND
SUSQUEHANNA REGION DRG THE DAY WED THO AMNTS MAY BE SLIGHTLY
HIGHER, THUS HV OPTED TO KEEP WARNINGS GOING FOR CNTRL NY.
SYSTEM WL BCM VERTICALLY STACKED DRG THE DAY TOMORROW AND WITH NW
FLOW MVG DOWN ACRS THE LKS EXPECT SNOW TO CONTINUE ON WEDNESDAY.
ONLY QUESTION WL BE IS IF DRY SLOT WL MV IN FM THE EAST AND
DENDRITE ZONE WL LOSE MOISTURE DRG THE AFTN HRS BUT WL ALLOW
LATER SHIFTS DECIDE ON DROPPING HEADLINES EARLY.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
3 PM UPDATE...
ON THURSDAY...LINGERING SNOW IS EXPECTED WITH MAINLY LOW
INTENSITIES. THE CYCLONE WILL STILL BE MOVING SLOWLY THROUGH
NORTHERN NEW ENGLAND WITH A PERSISTENT NORTHWEST FLOW ACROSS NY
AND PA.
THE NORTHWEST FLOW WILL ACTIVATE THE LAKES, BUT TO WHAT TO DEGREE?
INVERSION HEIGHTS ARE LOW AND WILL BE LOWERING THROUGHOUT THE
LATE AFTERNOON HOURS AND INTO THE EVENING. MOISTURE IS LIMITED
TOO. SO...WENT FOR SOMEWHAT HIGHER POPS DOWNWIND OF THE LAKES BUT
KEPT SNOW TOTALS ON THE LIGHT SIDE.
130 PM UPDATE...
LARGE STACKED LOW STILL OVER NEW ENGLAND ON THURSDAY. SNOW WILL
CONTINUE WITH THE GREATEST AMOUNTS OVER NY. NOT COLD ENOUGH FOR
SIGNIFICANT LAKE EFFECT BUT SOME ENHANCEMENT LIKELY THU AND FRI.
FRI NGT ON LOW MOVES EAST AND UL RIDGE AND SFC HIGH MOVES IN FROM
WEST. AS TYPICAL GFS FASTER THAN EURO. POPS LOW ENOUGH THAT KEPT
THE CWA DRY FRI NGT TO TUESDAY. SUNDAY TO MONDAY WAA INCREASES ON
THE BACK SIDE OF THE RIDGE SFC AND ALOFT. TEMPERATURES WITHIN 5
DEGREES OF AVERAGE.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
RAIN WITH POCKETS OF FREEZING RAIN WILL CHANGE TO SNOW AND SNOW
SHOWERS TONIGHT AS LOW PRESSURE REMAINS NEARLY STATIONARY ALONG
THE EAST COAST. SNOW SHOWERS WILL PERSIST THROUGH WEDNESDAY. CIGS
WILL BE MOSTLY MVFR WITH AREAS OF IFR ESPECIALLY ON HILL TOP
AIRPORTS SUCH AS ITH AND BGM. VSBYS WILL FALL TO IFR AS
PRECIPITATION CHANGES TO SNOW AND SNOW SHOWERS TONIGHT. WINDS WILL
BE LIGHT AND VARIABLE BECOMING NORTH AT 5 TO 10 KTS THIS AFTERNOON
THEN NORTHWEST AT 10 TO 15 KTS TONIGHT AND WEDNESDAY WITH GUSTS OF
20 TO 25 KTS WEDNESDAY.
OUTLOOK...
TUE NGT THROUGH WED...MVFR/IFR IN SNOW OR BLSN. NEAR AIRPORT MINS AT
TIMES IN BANDS OF HEAVY SNOW TUE NGT-EARLY WED.
THU/FRI...RESTRICTIONS POSSIBLE IN SHSN. BETTER CHC IN NY.
SAT...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR PAZ039-040.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR PAZ038-043-
044-047-048-072.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ009-
015>018-023-025-036-037-044>046-055>057.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR NYZ022-024-
062.
&&
$$
SYNOPSIS...PVF
NEAR TERM...PVF
SHORT TERM...PVF
LONG TERM...DJP/TAC
AVIATION...DJP/MSE
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
109 PM EST TUE DEC 9 2014
.SYNOPSIS...
A VERY SLOWLY MOVING NOR EASTER WILL HAVE A LARGE IMPACT ON THE
REGION. MIXED PRECIPITATION WILL BEGIN TO MIX WITH AND CHANGE TO
SNOW TONIGHT. LIGHT SNOW ACCUMULATIONS ARE EXPECTED AREAWIDE THROUGH
THURSDAY MORNING...AS WELL AS SOME LIGHT ICE ACCUMULATIONS MAINLY AT
HIGHER ELEVATIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
1 PM UPDATE...
SFC LOPRES HAS DROPPED DOWN TO NR 1000MB AS IT SPINS OFF THE JERSEY
SHORE. MODERATE TO HVY PCPN IS ONGOING ACRS ERN HALF OF CWA AS
EXPECTED BUT THERMAL PROFILES ARE TOO WARM FOR SNOW. SOME HIGHER
ELEVATION SITES ARE STILL RIGHT AT OR BLO FRZG AS OF 17Z WITH -FZRA
FALLING AT THESE LOCATIONS AND HEARING ABOUT NUMEROUS MOTOR VEHICLE
ACCIDENTS.
PCPN HAS ESSENTIALLY HIT A BRICK WALL AT THE I-81 CORRIDOR AND NOT
EXPECTING THIS TO MV MUCH FURTHER EAST THAN WHERE IT CURRENTLY IS
NOW UNTIL AFT 00Z. DEFORMATION BAND THAT THE MODELS WERE INSISTENT
WUD ROTATE WEST THRU THE EVNG HRS IS NOW LOOKING TO BE A FRACTURED
BAND OF MIXED PCPN.
H9 TEMPS PER LATEST RUC MODEL INDICATING BLYR TEMPS RMNG ISOTHERMAL
THRU 21Z THIS AFTN AND VRY SLOWLY DROPPING BYND THIS TIME. EXPECT A
MIXED BAG THRU BULK OF THE OVRNGT FOR SXNS EAST OF I-81 WITH CLD AIR
BEING PULLED IN FM THE WEST. ANOTHER WV FCST TO MV THRU NRN ZONES
AFT 06Z TONIGHT AND WITH MOISTURE FM LK ADDED IN EXPECT SVRL INCHES
OF SNOW TO FALL ACRS THE FINGER LKS BY 12Z. STORM TOTAL SNOWFALL
THRU THE OVRNGT IS NOW LOOKING TO BE MEAGER WITH A GNRL INCH OR TWO
ACRS THE BULK OF THE AREA AND POSSIBLY 2-4 INCHES IN HIGHER
ELEVATIONS OF SUSQUEHANNA REGION. WL DRASTICALLY BE REDUCING SNOW
TOTALS FOR THIS EVENT AND WL ALLOW LATER SHIFTS TO MAKE DECISION ON
WHETHER TO CANCEL OR DROP WARNINGS DOWN TO ADVISORY.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
425 AM UPDATE...
NOR` EASTER WILL CONTINUE TO IMPACT THE AREA...BECAUSE IT
BASICALLY RUNS INTO A BRICK WALL /IN THE FORM OF A VERY STRONG 1045MB
HIGH PRESSURE CENTER IN CANADA/ AND SO HAS NOWHERE TO GO.
REMAINS OF INITIAL DEFORMATION BAND WILL BE OVER THE CENTRAL
SOUTHERN TIER-FINGER LAKES AREA EARLY WEDNESDAY MORNING...WHILE
LIGHTER SNOW AND OR FREEZING RAIN-DRIZZLE OCCURS IN THE CENTRAL TO
EASTERN ZONES. HOWEVER...THE NOR` EASTER BECOMES VERTICALLY
STACKED...WHICH MEANS WE WILL BE VULNERABLE TO ADDITIONAL WAVES
ROTATING AROUND IT. MOST GUIDANCE SHOWS ANOTHER SUCH WAVE OF
MOISTURE SPINNING UP INTO NEW ENGLAND WEDNESDAY MORNING...THEN
WRAPPING BACK ACROSS OUR WEDNESDAY AFTERNOON THROUGH NIGHT. THIS
WILL KEEP /OR RETURN/ ACCUMULATING SNOWS ACROSS THE WARNING
AREA...HEAVIEST ACROSS OUR NEW YORK ZONES.
ALSO...THE STACKED LOW WILL WOBBLE AND THEN RELOCATE DIRECTLY OVER
OUR REGION /INSTEAD OF THE COAST/. NORTHWESTERLY WINDS WILL ADVECT
COLDER AIR ACROSS OUR REGION AS THIS OCCURS...SO THE SNOW WILL BE
OF A FLUFFIER LOWER WATER CONTENT TEXTURE WITH TIME /ESPECIALLY
WEDNESDAY NIGHT WITH TEMPERATURES FALLING THROUGH 20S/. IT WILL
BECOME MORE SUSCEPTIBLE TO BLOWING AND DRIFTING...THOUGH WINDS
THEMSELVES WILL LUCKILY DIMINISH WITH TIME AS WELL.
ALL TOLD...STORM SNOW TOTALS...HEAVILY DEPENDENT ON ELEVATION...ARE
EXPECTED TO WIDELY RANGE FROM ABOUT A HALF FOOT TO A FOOT OR
MORE...HIGHEST IN THE WESTERN CATSKILLS. POINTS OF UNCERTAINTY
INCLUDE EXACT POSITIONING AND INTENSITY OF THE MESOSCALE
BAND...HOW WELL THE PRIMARY BAND HANGS TOGETHER WHILE SHIFTING
WEST AWAY FROM CATSKILLS-POCONOS TONIGHT...AND HOW LOW THE
SNOWFALL-TO-LIQUID RATIOS WILL BE /AND THE IMPACT ON TOTALS/.
ESPECIALLY DURING THE FIRST HALF OF THE EVENT...THIS WILL NOT BE A
FLUFFY EAST-TO-SHOVEL SNOW...BUT RATHER...OF THE WET CRUSTY DENSE
KIND ESPECIALLY LOWER ELEVATIONS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
3 PM UPDATE...
ON THURSDAY...LINGERING SNOW IS EXPECTED WITH MAINLY LOW
INTENSITIES. THE CYCLONE WILL STILL BE MOVING SLOWLY THROUGH
NORTHERN NEW ENGLAND WITH A PERSISTENT NORTHWEST FLOW ACROSS NY
AND PA.
THE NORTHWEST FLOW WILL ACTIVATE THE LAKES, BUT TO WHAT TO DEGREE?
INVERSION HEIGHTS ARE LOW AND WILL BE LOWERING THROUGHOUT THE
LATE AFTERNOON HOURS AND INTO THE EVENING. MOISTURE IS LIMITED
TOO. SO...WENT FOR SOMEWHAT HIGHER POPS DOWNWIND OF THE LAKES BUT
KEPT SNOW TOTALS ON THE LIGHT SIDE.
130 PM UPDATE...
LARGE STACKED LOW STILL OVER NEW ENGLAND ON THURSDAY. SNOW WILL
CONTINUE WITH THE GREATEST AMOUNTS OVER NY. NOT COLD ENOUGH FOR
SIGNIFICANT LAKE EFFECT BUT SOME ENHANCEMENT LIKELY THU AND FRI.
FRI NGT ON LOW MOVES EAST AND UL RIDGE AND SFC HIGH MOVES IN FROM
WEST. AS TYPICAL GFS FASTER THAN EURO. POPS LOW ENOUGH THAT KEPT
THE CWA DRY FRI NGT TO TUESDAY. SUNDAY TO MONDAY WAA INCREASES ON
THE BACK SIDE OF THE RIDGE SFC AND ALOFT. TEMPERATURES WITHIN 5
DEGREES OF AVERAGE.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
RAIN WITH POCKETS OF FREEZING RAIN WILL CHANGE TO SNOW AND SNOW
SHOWERS TONIGHT AS LOW PRESSURE REMAINS NEARLY STATIONARY ALONG
THE EAST COAST. SNOW SHOWERS WILL PERSIST THROUGH WEDNESDAY. CIGS
WILL BE MOSTLY MVFR WITH AREAS OF IFR ESPECIALLY ON HILL TOP
AIRPORTS SUCH AS ITH AND BGM. VSBYS WILL FALL TO IFR AS
PRECIPITATION CHANGES TO SNOW AND SNOW SHOWERS TONIGHT. WINDS WILL
BE LIGHT AND VARIABLE BECOMING NORTH AT 5 TO 10 KTS THIS AFTERNOON
THEN NORTHWEST AT 10 TO 15 KTS TONIGHT AND WEDNESDAY WITH GUSTS OF
20 TO 25 KTS WEDNESDAY.
OUTLOOK...
TUE NGT THROUGH WED...MVFR/IFR IN SNOW OR BLSN. NEAR AIRPORT MINS AT
TIMES IN BANDS OF HEAVY SNOW TUE NGT-EARLY WED.
THU/FRI...RESTRICTIONS POSSIBLE IN SHSN. BETTER CHC IN NY.
SAT...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR PAZ038>040-
043-044-047-048-072.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ009-
015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...MDP
NEAR TERM...PVF
SHORT TERM...MDP
LONG TERM...DJP/TAC
AVIATION...DJP/MSE
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
101 PM EST TUE DEC 9 2014
.SYNOPSIS...
A VERY SLOWLY MOVING NOR EASTER WILL HAVE A LARGE IMPACT ON THE
REGION. MIXED PRECIPITATION WILL BEGIN TO MIX WITH AND CHANGE TO
SNOW TONIGHT. LIGHT SNOW ACCUMULATIONS ARE EXPECTED AREAWIDE THROUGH
THURSDAY MORNING...AS WELL AS SOME LIGHT ICE ACCUMULATIONS MAINLY AT
HIGHER ELEVATIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
1 PM UPDATE...
SFC LOPRES HAS DROPPED DOWN TO NR 1000MB AS IT SPINS OFF THE JERSEY
SHORE. MODERATE TO HVY PCPN IS ONGOING ACRS ERN HALF OF CWA AS
EXPECTED BUT THERMAL PROFILES ARE TOO WARM FOR SNOW. SOME HIGHER
ELEVATION SITES ARE STILL RIGHT AT OR BLO FRZG AS OF 17Z WITH -FZRA
FALLING AT THESE LOCATIONS AND HEARING ABOUT NUMEROUS MOTOR VEHICLE
ACCIDENTS.
PCPN HAS ESSENTIALLY HIT A BRICK WALL AT THE I-81 CORRIDOR AND NOT
EXPECTING THIS TO MV MUCH FURTHER EAST THAN WHERE IT CURRENTLY IS
NOW UNTIL AFT 00Z. DEFORMATION BAND THAT THE MODELS WERE INSISTENT
WUD ROTATE WEST THRU THE EVNG HRS IS NOW LOOKING TO BE A FRACTURED
BAND OF MIXED PCPN.
H9 TEMPS PER LATEST RUC MODEL INDICATING BLYR TEMPS RMNG ISOTHERMAL
THRU 21Z THIS AFTN AND VRY SLOWLY DROPPING BYND THIS TIME. EXPECT A
MIXED BAG THRU BULK OF THE OVRNGT FOR SXNS EAST OF I-81 WITH CLD AIR
BEING PULLED IN FM THE WEST. ANOTHER WV FCST TO MV THRU NRN ZONES
AFT 06Z TONIGHT AND WITH MOISTURE FM LK ADDED IN EXPECT SVRL INCHES
OF SNOW TO FALL ACRS THE FINGER LKS BY 12Z. STORM TOTAL SNOWFALL
THRU THE OVRNGT IS NOW LOOKING TO BE MEAGER WITH A GNRL INCH OR TWO
ACRS THE BULK OF THE AREA AND POSSIBLY 2-4 INCHES IN HIGHER
ELEVATIONS OF SUSQUEHANNA REGION. WL DRASTICALLY BE REDUCING SNOW
TOTALS FOR THIS EVENT AND WL ALLOW LATER SHIFTS TO MAKE DECISION ON
WHETHER TO CANCEL OR DROP WARNINGS DOWN TO ADVISORY.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
425 AM UPDATE...
NOR` EASTER WILL CONTINUE TO IMPACT THE AREA...BECAUSE IT
BASICALLY RUNS INTO A BRICK WALL /IN THE FORM OF A VERY STRONG 1045MB
HIGH PRESSURE CENTER IN CANADA/ AND SO HAS NOWHERE TO GO.
REMAINS OF INITIAL DEFORMATION BAND WILL BE OVER THE CENTRAL
SOUTHERN TIER-FINGER LAKES AREA EARLY WEDNESDAY MORNING...WHILE
LIGHTER SNOW AND OR FREEZING RAIN-DRIZZLE OCCURS IN THE CENTRAL TO
EASTERN ZONES. HOWEVER...THE NOR` EASTER BECOMES VERTICALLY
STACKED...WHICH MEANS WE WILL BE VULNERABLE TO ADDITIONAL WAVES
ROTATING AROUND IT. MOST GUIDANCE SHOWS ANOTHER SUCH WAVE OF
MOISTURE SPINNING UP INTO NEW ENGLAND WEDNESDAY MORNING...THEN
WRAPPING BACK ACROSS OUR WEDNESDAY AFTERNOON THROUGH NIGHT. THIS
WILL KEEP /OR RETURN/ ACCUMULATING SNOWS ACROSS THE WARNING
AREA...HEAVIEST ACROSS OUR NEW YORK ZONES.
ALSO...THE STACKED LOW WILL WOBBLE AND THEN RELOCATE DIRECTLY OVER
OUR REGION /INSTEAD OF THE COAST/. NORTHWESTERLY WINDS WILL ADVECT
COLDER AIR ACROSS OUR REGION AS THIS OCCURS...SO THE SNOW WILL BE
OF A FLUFFIER LOWER WATER CONTENT TEXTURE WITH TIME /ESPECIALLY
WEDNESDAY NIGHT WITH TEMPERATURES FALLING THROUGH 20S/. IT WILL
BECOME MORE SUSCEPTIBLE TO BLOWING AND DRIFTING...THOUGH WINDS
THEMSELVES WILL LUCKILY DIMINISH WITH TIME AS WELL.
ALL TOLD...STORM SNOW TOTALS...HEAVILY DEPENDENT ON ELEVATION...ARE
EXPECTED TO WIDELY RANGE FROM ABOUT A HALF FOOT TO A FOOT OR
MORE...HIGHEST IN THE WESTERN CATSKILLS. POINTS OF UNCERTAINTY
INCLUDE EXACT POSITIONING AND INTENSITY OF THE MESOSCALE
BAND...HOW WELL THE PRIMARY BAND HANGS TOGETHER WHILE SHIFTING
WEST AWAY FROM CATSKILLS-POCONOS TONIGHT...AND HOW LOW THE
SNOWFALL-TO-LIQUID RATIOS WILL BE /AND THE IMPACT ON TOTALS/.
ESPECIALLY DURING THE FIRST HALF OF THE EVENT...THIS WILL NOT BE A
FLUFFY EAST-TO-SHOVEL SNOW...BUT RATHER...OF THE WET CRUSTY DENSE
KIND ESPECIALLY LOWER ELEVATIONS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
3 PM UPDATE...
ON THURSDAY...LINGERING SNOW IS EXPECTED WITH MAINLY LOW
INTENSITIES. THE CYCLONE WILL STILL BE MOVING SLOWLY THROUGH
NORTHERN NEW ENGLAND WITH A PERSISTENT NORTHWEST FLOW ACROSS NY
AND PA.
THE NORTHWEST FLOW WILL ACTIVATE THE LAKES, BUT TO WHAT TO DEGREE?
INVERSION HEIGHTS ARE LOW AND WILL BE LOWERING THROUGHOUT THE
LATE AFTERNOON HOURS AND INTO THE EVENING. MOISTURE IS LIMITED
TOO. SO...WENT FOR SOMEWHAT HIGHER POPS DOWNWIND OF THE LAKES BUT
KEPT SNOW TOTALS ON THE LIGHT SIDE.
130 PM UPDATE...
LARGE STACKED LOW STILL OVER NEW ENGLAND ON THURSDAY. SNOW WILL
CONTINUE WITH THE GREATEST AMOUNTS OVER NY. NOT COLD ENOUGH FOR
SIGNIFICANT LAKE EFFECT BUT SOME ENHANCEMENT LIKELY THU AND FRI.
FRI NGT ON LOW MOVES EAST AND UL RIDGE AND SFC HIGH MOVES IN FROM
WEST. AS TYPICAL GFS FASTER THAN EURO. POPS LOW ENOUGH THAT KEPT
THE CWA DRY FRI NGT TO TUESDAY. SUNDAY TO MONDAY WAA INCREASES ON
THE BACK SIDE OF THE RIDGE SFC AND ALOFT. TEMPERATURES WITHIN 5
DEGREES OF AVERAGE.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SCATTERED FREEZING RAIN IS OVER AVP AND BGM THIS MORNING. A RAIN/FREEZING
RAIN MIX IS FORECAST TO SPREAD INTO ELM, SYR, ITH, AND RME BETWEEN
14Z AND 17Z, THEN CHANGE TO ALL RAIN FOR THE MID AFTERNOON.
WIDESPREAD MVFR CONDITIONS ARE FORECAST WITH THE PRECIPITATION
ARRIVAL. BGM AND ITH WILL LIKELY HAVE IFR CEILINGS.
THE PRECIPITATION WILL CHANGE TO SNOW DURING THE LATE AFTERNOON,
WITH IFR CONDITIONS FORECAST THROUGH THE EVENING AND OVERNIGHT
HOURS IN MODERATE SNOW.
OUTLOOK...
TUE NGT THROUGH WED...MVFR/IFR IN SNOW OR BLSN. NEAR AIRPORT MINS AT
TIMES IN BANDS OF HEAVY SNOW TUE NGT-EARLY WED.
THU/FRI...RESTRICTIONS POSSIBLE IN SHSN. BETTER CHC IN NY.
SAT...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR PAZ038>040-
043-044-047-048-072.
NY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR NYZ009-
015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...MDP
NEAR TERM...PVF
SHORT TERM...MDP
LONG TERM...DJP/TAC
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1010 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE VIRGINIA COAST WILL LIFT NORTH OF THE REGION
TODAY. HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTHWEST
WEDNESDAY AND THURSDAY AND REMAIN OVER THE REGION INTO THIS
WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
AS OF 1010 AM TUESDAY...MORNING UPDATE MAINLY TO CAPTURE PRECIP AND
T/TD TRENDS. THE SFC LOW IS LOCATED APPROX 100 MI E OF THE
DELMARVA PENINSULAR THIS MORNING AND WILL CONTINUE TO LIFT NORTH
TO OFF THE NJ COAST TODAY AS A SHARP UPPER TROUGH DIGS ALONG THE
EASTERN SEABOARD. DEEP MOISTURE CONTINUES TO LIFT N ACROSS THE
AREA AHEAD OF THE UPPER TROUGH WITH DRIZZLE/SPRINKLES MAINLY OVER
THE AREA. WRAP AROUND MOISTURE WILL CONTINUE TO BRING THE THREAT
OF LIGHT SHOWERS AS THE SFC LOW LIFTS NORTH OF THE AREA TODAY WITH
SOME RAIN NOTED NEAR ROCKY MOUNT AND LOUISBURG CURRENTLY. RAINFALL
AMOUNTS WILL BE LIGHT...GENERALLY LESS THAN A TENTH OF AN INCH.
MODEL SOUNDINGS INDICATE LOW CLOUDS AND BREEZY TO WINDY NORTHERLY
FLOW WILL PERSIST THROUGH THE MUCH DAY PRODUCING RAW CONDITIONS
WITH HIGHS IN THE MID TO UPPER 40S INLAND TO LOWER 50S ALONG THE
COAST.
THE HIGH SURF ADVISORY AND COASTAL FLOOD ADVISORY FOR THE OUTER
BANKS NORTH OF CAPE HATTERAS WILL END SHORTLY WITH REPORTS OF
OCEAN OVERWASH AGAIN FROM BUXTON NORTH TO PEA ISLAND.
&&
.SHORT TERM /TONIGHT/...
AS OF 330 AM TUE...THE UPPER TROUGH DEVELOPS INTO A CUT-OFF LOW
ACROSS THE MID ATLANTIC TONIGHT WHILE A ROBUST SHORTWAVE ROTATES
THROUGH THE BASE OF THE LOW AND ACROSS THE CAROLINAS. ENOUGH UPPER
LEVEL DYNAMICS AND WRAP AROUND MOISTURE TO CONTINUE RAIN CHANCES
TONIGHT...MAINLY THROUGH THE EVENING HOURS WITH BETTER CHANCES
NORTHERN SECTIONS. AFTER THE EMBEDDED SHORTWAVE MOVES OFFSHORE
LATE TONIGHT NWLY FLOW DEVELOPS BRINGING DRYING THROUGH THE COLUMN
WITH RAIN CHANCES DIMINISHING. AGAIN...RAINFALL AMOUNTS WILL BE
LIGHT WITH ONLY A FEW HUNDREDTHS EXPECTED. LOWS EXPECTED IN THE
MID TO UPPER 30S INLAND TO MID 40S COAST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 245 AM TUESDAY...DEEP MID-LEVEL TROUGH TO LINGER NEAR THE
NORTH CAROLINA COAST WEDNESDAY UNTIL LIFTING NORTH THURSDAY AS
THE UPPER LEVEL FLOW GRADUALLY BECOMES MORE ZONAL WITH THE TROUGH
AXIS GRADUALLY MOVING OFFSHORE BY LATE WEEK. AT THE SURFACE...LOW
PRESSURE OVER SOUTHERN NEW ENGLAND WILL SLOWLY MOVE NORTH AND
WEAKEN WITH A DOWNSLOPING W/WNW FLOW DEVELOPING ACROSS THE REGION
WEDNESDAY AND WEAKENING A BIT ON THURSDAY. SURFACE HIGH PRESSURE
THEN BUILDS EAST FOR LATE WEEK WITH AN UPPER RIDGE BUILDING NORTH
FROM THE GULF SUNDAY INTO MONDAY. THIS WILL MAKE FOR A DRY
FORECAST FOR WEDNESDAY INTO THE WEEKEND. TEMPERATURES...ESPECIALLY
MINIMUMS WILL BE BELOW NORMAL THURSDAY INTO SATURDAY WITH MANY
AREAS AT OR BELOW FREEZING...ESPECIALLY INLAND. DAYTIME HIGHS WILL
BE CHILLY...ESPECIALLY THURSDAY AND FRIDAY WITH HIGHS UPPER 40S TO
AROUND 50. AS THE UPPER HIGH BUILDS FROM THE SOUTH...TEMPERATURES
WARM TO NEAR OR SLIGHTLY ABOVE NORMAL LEVELS WITH LOWER 60S FOR
HIGHS BY MONDAY AND TUESDAY. MOISTURE STARTS TO CREEP NORTH FROM
THE GULF OF MEXICO WITH A CHANCE OF RAIN RETURNING TO THE REGION
BY TUESDAY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 630 AM TUESDAY...LOW PRES LIFTING NORTH JUST OFF THE VA COAST
THIS MORNING. BULK OF THE RAIN ASSOC WITH MID LEVEL ENERGY HAS
MOVED EAST OF THE TERMINALS WITH ABUNDANT LOW LEVEL MOISTURE
ALLOWING LIFR CONDITIONS TO PREVAIL. NW FLOW AND LOW LEVEL WRAP-
AROUND MOISTURE WILL PERSIST TODAY BRINGING A PROLONGED PERIOD OF
CIGS AOB IFR...AND POSSIBLY A FEW SHOWERS ACROSS THE AREA. SREF AND
NAM STILL APPEAR TO LIFT CIGS TO MVFR TOO QUICKLY THIS MORNING
WHILE THE GFS AND HRRR SOLUTIONS KEEP IFR CIGS THROUGH THE
AFTERNOON AND EVEN INTO THE EVENING FOR THE COASTAL TAF SITES.
MODEL SOUNDING SHOWING COOLING TEMPS ABOVE THE LOW LEVEL INVERSION
THROUGH THE AFTERNOON AND THINK THE GFS/HRRR MAY BE HOLDING ON TO
IFR CIGS A LITTLE TOO LONG AND HAVE ESSENTIALLY SPLIT THE
DIFFERENCE TIMING WISE FOR WHEN CIGS LIFT TO MVFR. MVFR CIGS WILL
LIKELY PERSIST THROUGH MUCH OF THE EVENING HOURS BUT MODEL
SOUNDINGS INDICATING SUBSTANTIAL DRYING THE COLUMN LATE TONIGHT AS
THE UPPER TROUGH LIFTS N AND DEVELOPS INTO A CUT-OFF LOW OVER THE
MID-ATLANTIC BRINGING NW FLOW ACROSS THE REGION AND EXPECT VFR
CONDITIONS TO RETURN AFTER MIDNIGHT.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 245 AM TUESDAY...WITH HIGH PRESSURE IN CONTROL AND A
DOWNSLOPING W/WNW SURFACE FLOW...EXPECT DRY CONDITIONS AND
GENERALLY VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. DEWPOINT
DEPRESSIONS AND LOW-LEVEL MIXING APPEARS TO BE SUFFICIENT TO
PRECLUDE MUCH IN THE WAY OF VISIBILITY-REDUCING FOG THROUGHOUT THE
PERIOD.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1010 AM TUESDAY...LATEST SURFACE AND BUOY DATA INDICATE NW
WINDS 10-20 KT WITH GUSTS TO 25 KT AT DUCK. SEAS REMAIN ELEVATED
9-12 FT NORTH OF OCRACOKE WITH 6-8 FT SOUTH. LOW PRESSURE OFF THE
DELMARVA PENINSULA THIS MORNING WILL LIFT NORTH TO OFF THE NJ
COAST TODAY. NW WINDS AROUND 15-25 KT THROUGHOUT THE COASTAL
WATERS AS THE LOW LIFTS NORTH OF THE AREA...WHICH IS EXPECTED TO
CONTINUE IN THIS GENERAL RANGE THROUGH THE SHORT TERM.
SEAS WILL VERY SLOWLY SUBSIDE THROUGH THE PERIOD...TO ABOUT 6-10
FT NORTH WHILE CONTINUING AROUND 5-8 FT SOUTHERN WATERS TONIGHT.
HAVE EXTENDED THE SCA FOR THE SOUNDS AND ALLIGATOR AS MODELS
INDICATING NW WINDS UP TO 25 KT CONTINUING ACROSS THE EASTERN
PORTIONS OF THESE ZONES THIS MORNING BUT OTHERWISE HAVE CONTINUED
THE SCA AS ADVERTISED.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 255 AM TUESDAY...WITH CYCLONIC FLOW AROUND LOW PRESSURE
MOVING ACROSS SOUTHERN NEW ENGLAND...EXPECT GUSTY WNW/NW WINDS
WEDNESDAY AND WEDNESDAY NIGHT BEFORE THE GRADIENT SUBSIDES A BIT
ON THURSDAY. SEAS WILL REMAIN ELEVATED...AS HIGH AS 10 FEET
WEDNESDAY AND WEDNESDAY NIGHT...BEFORE SUBSIDING BY THURSDAY
NIGHT. THE SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 PM
THURSDAY FOR THE NORTHERN AND SOUTHERN WATERS AND UNTIL 11 PM
THURSDAY FOR THE CENTRAL WATERS. LATEST SWAN AND WAVEWATCH
INDICATE THAT SEAS FINALLY DROP BELOW 6 FEET THURSDAY EVENING.
AFTER A BIT OF A LULL ON FRIDAY...WINDS/SEAS INCREASE AGAIN
SATURDAY AS GRADIENT IS PINCHED WITH SURFACE HIGH PRESSURE
BUILDING TO THE EAST AND SOME MINIMAL SMALL CRAFT ADVISORY
CONDITIONS WILL BE POSSIBLE ONCE AGAIN.
&&
.TIDES/COASTAL FLOODING...
AS OF 315 AM TUESDAY...LOW PRES TRACKING NORTH JUST OFF THE COAST
THIS MORNING BRINGING STRONG NLY WINDS ACROSS THE OBX WHICH...
COMBINED WITH LARGE HIGH ENERGY SEAS ON THE ORDER OF 10-15 FT WITH
PERIODS AROUND 12 SECONDS...WILL CONTINUE TO BRING LARGE SURF AND
WAVE RUN-UP ALONG THE BEACHES NORTH OF CAPE HATTERAS. OVERWASH
IS LIKELY AGAIN WITH THIS MORNINGS HIGH TIDE CYCLE...WHICH PEAKS
AROUND 9 AM. MOST VULNERABLE AREAS WILL BE WHERE THE DUNES HAVE
BREACHED DURING PREVIOUS HIGH TIDE CYCLES...INCLUDING KITTY
HAWK...PORTIONS OF PEA ISLAND INCLUDING THE S-CURVES AT MIRLO
BEACH...AND THE HOTELS IN BUXTON.
THE WINDS WILL SHIFT TO NW LATER THIS MORNING AS THE LOW BEGINS TO
LIFT NORTH OF THE AREA ALLOWING FOR GRADUALLY SUBSIDING SEAS AND
IMPROVING CONDITIONS WITH EACH SUBSEQUENT TIDE CYCLE. MINOR EFFECTS
MAY LINGER INTO WEDNESDAY MORNING WITH EXTRA-TROPICAL STORM SURGE
GUIDANCE INDICATING ABOVE NORMAL TIDES CONTINUING...BUT MUCH
IMPROVED CONDITIONS EXPECTED THURSDAY AND FRIDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HIGH SURF ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR NCZ103.
COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR NCZ103.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR AMZ130-
131-135.
SMALL CRAFT ADVISORY UNTIL 11 PM EST THURSDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THURSDAY FOR AMZ150-156-
158.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK/DAG
SHORT TERM...SK
LONG TERM...CTC
AVIATION...CTC/SK
MARINE...CTC/SK/DAG
TIDES/COASTAL FLOODING...SK
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
640 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE VIRGINIA COAST WILL LIFT NORTH OF THE REGION
TODAY. HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTHWEST
WEDNESDAY AND THURSDAY AND REMAIN OVER THE REGION INTO THIS
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM TUE...MORNING UPDATE MAINLY TO CAPTURE PRECIP AND
T/TD TRENDS. THE SFC LOW IS LOCATED APPROX 100 MI E OF VIRGINIA
BEACH EARLY THIS MORNING AND WILL CONTINUE TO LIFT NORTH TO OFF
THE NJ COAST TODAY AS A SHARP UPPER TROUGH DIGS ALONG THE EASTERN
SEABOARD. DEEP MOISTURE CONTINUES TO LIFT N ACROSS THE AREA AHEAD
OF THE UPPER TROUGH WITH LIGHT RAIN NOW MAINLY OVER DARE/HYDE
COUNTIES. HRRR LIFTS THE BULK OF THE RAINFALL NORTH OF THE AREA
BETWEEN 8-9 AM BUT WRAP AROUND MOISTURE WILL CONTINUE TO BRING THE
THREAT OF LIGHT SHOWERS AS THE SFC LOW LIFTS NORTH OF THE AREA
WITH BEST CHANCES NORTHERN AREAS. RAINFALL AMOUNTS WILL BE
LIGHT...GENERALLY LESS THAN A TENTH OF AN INCH. MODEL SOUNDINGS
INDICATE LOW CLOUDS AND BREEZY TO WINDY NORTHERLY FLOW WILL
PERSIST THROUGH THE MUCH DAY PRODUCING RAW CONDITIONS WITH HIGHS
IN THE MID TO UPPER 40S INLAND TO LOWER 50S ALONG THE COAST.
THE HIGH SURF ADVISORY AND COASTAL FLOOD ADVISORY FOR THE OUTER
BANKS NORTH OF CAPE HATTERAS CONTINUES THROUGH THE 9 AM HIGH TIDE
CYCLE. PLEASE SEE THE TIDES AND COASTAL FLOODING SECTION BELOW FOR
DETAILS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
AS OF 330 AM TUE...THE UPPER TROUGH DEVELOPS INTO A CUT-OFF LOW
ACROSS THE MID ATLANTIC TONIGHT WHILE A ROBUST SHORTWAVE ROTATES
THROUGH THE BASE OF THE LOW AND ACROSS THE CAROLINAS. ENOUGH UPPER
LEVEL DYNAMICS AND WRAP AROUND MOISTURE TO CONTINUE RAIN CHANCES
TONIGHT...MAINLY THROUGH THE EVENING HOURS WITH BETTER CHANCES
NORTHERN SECTIONS. AFTER THE EMBEDDED SHORTWAVE MOVES OFFSHORE
LATE TONIGHT NWLY FLOW DEVELOPS BRINGING DRYING THROUGH THE COLUMN
WITH RAIN CHANCES DIMINISHING. AGAIN...RAINFALL AMOUNTS WILL BE
LIGHT WITH ONLY A FEW HUNDREDTHS EXPECTED. LOWS EXPECTED IN THE
MID TO UPPER 30S INLAND TO MID 40S COAST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 245 AM TUESDAY...DEEP MID-LEVEL TROUGH TO LINGER NEAR THE
NORTH CAROLINA COAST WEDNESDAY UNTIL LIFTING NORTH THURSDAY AS
THE UPPER LEVEL FLOW GRADUALLY BECOMES MORE ZONAL WITH THE TROUGH
AXIS GRADUALLY MOVING OFFSHORE BY LATE WEEK. AT THE SURFACE...LOW
PRESSURE OVER SOUTHERN NEW ENGLAND WILL SLOWLY MOVE NORTH AND
WEAKEN WITH A DOWNSLOPING W/WNW FLOW DEVELOPING ACROSS THE REGION
WEDNESDAY AND WEAKENING A BIT ON THURSDAY. SURFACE HIGH PRESSURE
THEN BUILDS EAST FOR LATE WEEK WITH AN UPPER RIDGE BUILDING NORTH
FROM THE GULF SUNDAY INTO MONDAY. THIS WILL MAKE FOR A DRY
FORECAST FOR WEDNESDAY INTO THE WEEKEND. TEMPERATURES...ESPECIALLY
MINIMUMS WILL BE BELOW NORMAL THURSDAY INTO SATURDAY WITH MANY
AREAS AT OR BELOW FREEZING...ESPECIALLY INLAND. DAYTIME HIGHS WILL
BE CHILLY...ESPECIALLY THURSDAY AND FRIDAY WITH HIGHS UPPER 40S TO
AROUND 50. AS THE UPPER HIGH BUILDS FROM THE SOUTH...TEMPERATURES
WARM TO NEAR OR SLIGHTLY ABOVE NORMAL LEVELS WITH LOWER 60S FOR
HIGHS BY MONDAY AND TUESDAY. MOISTURE STARTS TO CREEP NORTH FROM
THE GULF OF MEXICO WITH A CHANCE OF RAIN RETURNING TO THE REGION
BY TUESDAY.
&&
.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 630 AM TUESDAY...LOW PRES LIFTING NORTH JUST OFF THE VA COAST
THIS MORNING. BULK OF THE RAIN ASSOC WITH MID LEVEL ENERGY HAS
MOVED EAST OF THE TERMINALS WITH ABUNDANT LOW LEVEL MOISTURE
ALLOWING LIFR CONDITIONS TO PREVAIL. NW FLOW AND LOW LEVEL WRAP-
AROUND MOISTURE WILL PERSIST TODAY BRINGING A PROLONGED PERIOD OF
CIGS AOB IFR...AND POSSIBLY A FEW SHOWERS ACROSS THE AREA. SREF AND
NAM STILL APPEAR TO LIFT CIGS TO MVFR TOO QUICKLY THIS MORNING
WHILE THE GFS AND HRRR SOLUTIONS KEEP IFR CIGS THROUGH THE
AFTERNOON AND EVEN INTO THE EVENING FOR THE COASTAL TAF SITES.
MODEL SOUNDING SHOWING COOLING TEMPS ABOVE THE LOW LEVEL INVERSION
THROUGH THE AFTERNOON AND THINK THE GFS/HRRR MAY BE HOLDING ON TO
IFR CIGS A LITTLE TOO LONG AND HAVE ESSENTIALLY SPLIT THE
DIFFERENCE TIMING WISE FOR WHEN CIGS LIFT TO MVFR. MVFR CIGS WILL
LIKELY PERSIST THROUGH MUCH OF THE EVENING HOURS BUT MODEL
SOUNDINGS INDICATING SUBSTANTIAL DRYING THE COLUMN LATE TONIGHT AS
THE UPPER TROUGH LIFTS N AND DEVELOPS INTO A CUT-OFF LOW OVER THE
MID-ATLANTIC BRINGING NW FLOW ACROSS THE REGION AND EXPECT VFR
CONDITIONS TO RETURN AFTER MIDNIGHT.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 245 AM TUESDAY...WITH HIGH PRESSURE IN CONTROL AND A
DOWNSLOPING W/WNW SURFACE FLOW...EXPECT DRY CONDITIONS AND
GENERALLY VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. DEWPOINT
DEPRESSIONS AND LOW-LEVEL MIXING APPEARS TO BE SUFFICIENT TO
PRECLUDE MUCH IN THE WAY OF VISIBILITY-REDUCING FOG THROUGHOUT THE
PERIOD.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 630 AM TUESDAY...LOW PRES APPROX 100 MI E OF VA BEACH EARLY
THIS MORNING WILL LIFT NORTH TO OFF THE NJ COAST TODAY. WINDS
BECOMING NW AROUND 15-25 KT THROUGHOUT THE COASTAL WATERS AS THE
LOW LIFTS NORTH OF THE AREA...WHICH IS EXPECTED TO CONTINUE IN
THIS GENERAL RANGE THROUGH THE SHORT TERM.
SEAS AROUND 10-14 FT NORTH OF OREGON INLET AND 5-8 FT SOUTH THIS
MORNING WILL VERY SLOWLY SUBSIDE THROUGH THE PERIOD...TO ABOUT
6-10 FT NORTH WHILE CONTINUING AROUND 5-8 FT SOUTHERN WATERS
TONIGHT. HAVE EXTENDED THE SCA FOR THE SOUNDS AND ALLIGATOR AS
MODELS INDICATING NW WINDS UP TO 25 KT CONTINUING ACROSS THE
EASTERN PORTIONS OF THESE ZONES THIS MORNING BUT OTHERWISE HAVE
CONTINUED THE SCA AS ADVERTISED.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 255 AM TUESDAY...WITH CYCLONIC FLOW AROUND LOW PRESSURE
MOVING ACROSS SOUTHERN NEW ENGLAND...EXPECT GUSTY WNW/NW WINDS
WEDNESDAY AND WEDNESDAY NIGHT BEFORE THE GRADIENT SUBSIDES A BIT
ON THURSDAY. SEAS WILL REMAIN ELEVATED...AS HIGH AS 10 FEET
WEDNESDAY AND WEDNESDAY NIGHT...BEFORE SUBSIDING BY THURSDAY
NIGHT. THE SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 PM
THURSDAY FOR THE NORTHERN AND SOUTHERN WATERS AND UNTIL 11 PM
THURSDAY FOR THE CENTRAL WATERS. LATEST SWAN AND WAVEWATCH
INDICATE THAT SEAS FINALLY DROP BELOW 6 FEET THURSDAY EVENING.
AFTER A BIT OF A LULL ON FRIDAY...WINDS/SEAS INCREASE AGAIN
SATURDAY AS GRADIENT IS PINCHED WITH SURFACE HIGH PRESSURE
BUILDING TO THE EAST AND SOME MINIMAL SMALL CRAFT ADVISORY
CONDITIONS WILL BE POSSIBLE ONCE AGAIN.
&&
.TIDES/COASTAL FLOODING...
AS OF 315 AM TUESDAY...LOW PRES TRACKING NORTH JUST OFF THE COAST
THIS MORNING BRINGING STRONG NLY WINDS ACROSS THE OBX WHICH...
COMBINED WITH LARGE HIGH ENERGY SEAS ON THE ORDER OF 10-15 FT WITH
PERIODS AROUND 12 SECONDS...WILL CONTINUE TO BRING LARGE SURF AND
WAVE RUN-UP ALONG THE BEACHES NORTH OF CAPE HATTERAS. OVERWASH
IS LIKELY AGAIN WITH THIS MORNINGS HIGH TIDE CYCLE...WHICH PEAKS
AROUND 9 AM. MOST VULNERABLE AREAS WILL BE WHERE THE DUNES HAVE
BREACHED DURING PREVIOUS HIGH TIDE CYCLES...INCLUDING KITTY
HAWK...PORTIONS OF PEA ISLAND INCLUDING THE S-CURVES AT MIRLO
BEACH...AND THE HOTELS IN BUXTON.
THE WINDS WILL SHIFT TO NW LATER THIS MORNING AS THE LOW BEGINS TO
LIFT NORTH OF THE AREA ALLOWING FOR GRADUALLY SUBSIDING SEAS AND
IMPROVING CONDITIONS WITH EACH SUBSEQUENT TIDE CYCLE. MINOR EFFECTS
MAY LINGER INTO WEDNESDAY MORNING WITH EXTRA-TROPICAL STORM SURGE
GUIDANCE INDICATING ABOVE NORMAL TIDES CONTINUING...BUT MUCH
IMPROVED CONDITIONS EXPECTED THURSDAY AND FRIDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HIGH SURF ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR NCZ103.
COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR NCZ103.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR AMZ130-
131-135.
SMALL CRAFT ADVISORY UNTIL 11 PM EST THURSDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THURSDAY FOR AMZ150-156-
158.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK
SHORT TERM...SK
LONG TERM...CTC
AVIATION...CTC/SK
MARINE...CTC/SK
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
338 PM CST TUE DEC 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 328 PM CST TUE DEC 9 2014
CHALLENGE CONTINUES TO BE EVOLUTION OF STRATUS DECK AND ITS IMPACT
ON TEMPS NOT ONLY TONIGHT BUT PROBABLY FOR THE NEXT FEW DAYS.
MODELS POOR WITH HANDLING THESE LOW LEVEL MOIST LAYERS IN THE COLD
SEASON...NOT MUCH CONFIDENCE WRT STRATUS AS A RESULT.
AFOREMENTIONED WARM UP BEGINS AS WEAK SHORT WAVE MOVES TO THE SE
TONIGHT AND 500MB HEIGHTS BEGIN TO BUILD. SFC WINDS TO REMAIN WELL
MIXED OVERNIGHT WITH WAA AS 850MB TEMPS BEGIN TO CLIMB...STRENGTHENING
THE INVERSION AND ALLOWING THE STRATUS DECK TO REMAIN ALL THE
WHILE LIMITING ANY FOG THAT WE SAW LAST NIGHT AS TEMPS FALL VERY
LITTLE OVERNIGHT.
WESTERN EDGE OF STRATUS DECK IS EXPECTED TO ERODE ACROSS THE DVL
BSN AND POSSIBLE INTO THE RRV. MID 30S IF CLOUDS SCT OUT OTHERWISE
THE UPR 20S CAN BE EXPECTED FOR WEDNESDAY MAX TEMPS. WEDNESDAY
NIGHT WILL CONTINUE TO SEE THE SOUTH WINDS AND DEAL WITH THE
THREAT OF A STRATUS DECK.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 328 PM CST TUE DEC 9 2014
THURSDAY TO FRIDAY RIDGING AT 500MB CONTINUES TO BUILD WITH
INCREASES THICKNESSES AND WARMING LOW LEVELS. HIGHS THURSDAY AND
FRIDAY WILL BE GOVERNED BY LOW LEVEL CLOUDS...MORE LIKELY THE
FARTHER EAST WHERE MIXING WILL BE LESS AND FLOW REMAINS TRULY
SOUTHERLY. THURSDAY MAX T 40S WEST MID 30S RRV AND LOW 30S EAST...FRIDAY
MORNING LOWS WILL BE NEAR NORMAL HIGHS WITH READINGS IN THE MID
20S WITH DAYTIME HIGHS INTO THE 40S RRV AND WEST WITH UPR 30S
EAST.
FRIDAY NIGHT THROUGH TUESDAY...THE UPPER RIDGING BUILDING OVER THE
UPPER MIDWEST WILL CONTINUE TO BRING WARMER THAN AVERAGE TEMPS INTO
THE WEEKEND. EVEN WITH CLOUDS LINGERING OVER THE EASTERN COUNTIES
THERE WILL BE ENOUGH WARM AIR MASS AND MOISTURE TO BRING TEMPS INTO
THE 30S AND EVEN SOME LOW 40S POSSIBLE IN THE SOUTH ON SATURDAY. THE
WINDS WILL SHIFT TO THE NORTHWEST AND START SCOURING OUT LOW LEVEL
MOISTURE ON SUNDAY...BUT WITH THE APPROACHING NORTHERN BRANCH
SHORTWAVE THERE WILL STILL BE CLOUDS AND AN INCREASING CHANCE FOR
PRECIP. WITH WARM TEMPS SATURDAY NIGHT AND SUNDAY KEPT A RAIN/SNOW
MIX IN THE SOUTH FOR NOW AND WILL REFINE AS THE TIME PERIOD GETS
CLOSER. AFTER THE COLD FRONT MOVES THROUGH ON SUNDAY...TEMPS WILL BE
CLOSER TO NORMAL WITH HIGHS IN THE 20S FOR MONDAY AND TUESDAY. THE
ECMWF HAS ANOTHER SHORTWAVE FOR TUESDAY WHILE THE GFS KEEPS RIDGING.
CONSIDERING NAEFS DOES NOT HAVE MUCH FOR PRECIP PROBABILITIES WILL
LEAN CLOSE TO ALLBLEND FOR NOW AND REMAIN DRY FOR THE EARLY PART OF
THE WORK WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1244 AM CST TUE DEC 9 2014
SOME OF THE LOW LEVEL CLOUDS HAVE CLEARED OUT OF THE NORTHERN RED
RIVER VALLEY AND THE DEVILS LAKE BASIN. HOWEVER...SOUTHERN LOCATIONS
ARE STILL SOCKED IN AND WINDS ARE FROM THE SOUTH...AND MORE STRATUS
IS OUT OVER WESTERN PORTIONS OF THE CWA. GFS AND SREF PROBABILITIES
ARE NOT HANDLING THE CURRENT LOW CLOUDS VERY WELL SO WILL DISREGARD
THOSE SOLUTIONS. THE NAM...HRRR...AND RAP ARE MUCH MORE PESSIMISTIC
FOR CIGS SO WILL LEAN IN THAT DIRECTION. THINK THAT THE SOUTHERN AND
EASTERN SPOTS THAT ARE STILL IFR WILL SEE SOME IMPROVEMENT TO MVFR
FOR A BRIEF PERIOD THIS AFTERNOON...BUT THEN GO BACK INTO THE SOUP
TONIGHT. THINK THERE SHOULD BE QUITE A LOT OF IFR CIGS...AND SOME
GUIDANCE IS PUTTING IN SOME VIS IN THE 3 TO 5SM RANGE...BUT WILL
JUST KEEP CIGS LOW FOR NOW AND ADD ANY VIS RESTRICTIONS LATER. WILL
CONTINUE TO KEEP STRATUS LINGERING OVER THE AREA THROUGH THE END OF
THE PERIOD AS THERE WILL BE SOUTH TO SOUTHEAST WINDS AT 10 TO 15 KTS
THAT WILL HAVE A TOUGH TIME SCOURING OUT CLOUDS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JK
LONG TERM...JK/JR
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1246 PM CST TUE DEC 9 2014
.UPDATE...
ISSUED AT 1244 AM CST TUE DEC 9 2014
TWEAKING SKY GRIDS AGAIN AS STRATUS DECK ACROSS THE DVL BASIN HAS
ERODED AND SKIES HAVE CLEARED. EXPECTING SOME LOW STRATUS TO
ADVECT NORTH NORTHWEST FROM MN SIDE OF RRV AS VISIBLE SATELLITE
SHOWS EDGE NEARING GFK. UNCERTAINTY ABOUNDS ON THE EVOLUTION OF
THE CLOUD DECK ACROSS E ND THIS EVENING AND OVERNIGHT.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 250 AM CST TUE DEC 9 2014
MAIN FORECAST CHALLENGES WILL BE DEALING WITH THE FOG/FLURRIES
AND LOW CLOUDS THAT CONTINUE TO PERSIST ACROSS MOST OF THE FA. AS
OF 3 AM QUITE A FEW STATIONS CONTINUED TO REPORT FOG OR FLURRIES
SO HAVE EXTENDED THE MENTION OF THESE THRU MID MORNING. ALSO KEPT
THE LOW CLOUDS ABOUT WHERE THEY WERE THRU MID MORNING AND THEN
TRIED TO FOLLOW A DECREASING TREND. WILL HAVE TO MONITOR THESE
THRU THE EARLY MORNING HOURS AND CONTINUE TO ADJUST IF NEED BE.
WITH THE SFC HIGH OVERHEAD AND LIGHT WINDS TURNING AROUND TO THE
SOUTH IN THE MORNING REALLY DO NOT EXPECT MUCH CHANGE IN THE
STATUS QUO. LARGER SCALE MODELS NOT HANDLING THESE DETAILS SO HAVE
LEANED MORE ON THE HIGH RESOLUTION RAP/HRRR. 850MB TEMPS CONTINUE
TO WARM TODAY GETTING TO ABOUT 2C-6C BY 00Z WED WHICH WILL ONLY
STRENGTHEN THE INVERSION...NOT HELPING TO GET RID OF THE LOW
CLOUDS. OF COURSE IF THE CLOUDS DO HANG AROUND LONGER THAN
EXPECTED THEY WILL HAVE A STAKE IN THE HIGH TEMP FORECAST. FOR NOW
PRETTY MUCH KEPT WITH THE PREVIOUS FORECAST WITH HIGHS IN THE LOW
TO MID 20S TODAY. THE SFC HIGH CONTINUES TO PUSH OFF TO THE EAST
TONIGHT WITH SOUTH WINDS STAYING UP. 850MB TEMPS CONTINUE TO RISE
TO ABOUT 6-8C BY 00Z THU WITH THE SOUTH WINDS CONTINUING. THESE
NOT FAVORABLE FOR A STRONG WARM UP AND THERE MAY STILL BE SOME
CLOUDS OVER THE AREA...SO TEMP FORECAST REMAINS TRICKY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 250 AM CST TUE DEC 9 2014
THE WARM 850MB TEMPS CONTINUE TO INCREASE OR TO ABOUT 10-12C BY
00Z FRI. STILL WILL HAVE SOUTH WINDS AND NOT VERY GOOD MIXING SO
KEPT HIGHS THU IN THE MID TO UPPER 30S.
FRIDAY-MONDAY...THE MAIN STORY WILL BE WELL ABOVE NORMAL
TEMPERATURES AT THE BEGINNING OF THIS PERIOD...FOLLOWED BY A COLD
FRONT AND MORE NORMAL TEMPERATURES TOWARD THE END OF THIS PERIOD.
GIVEN LACK OF SNOW COVER ACROSS A MAJORITY OF THE REGION...HOW WARM
DAYTIME TEMPERATURES GET WILL BE A CHALLENGE. THE OTHER CONCERN WILL
BE LOW STRATUS AND POTENTIALLY FOG/DRIZZLE/FREEZING DRIZZLE WITH THE
REGION WITHIN AN INVERTED TROUGH FROM A SOUTHERN SYSTEM LATER
SATURDAY INTO SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1244 AM CST TUE DEC 9 2014
SOME OF THE LOW LEVEL CLOUDS HAVE CLEARED OUT OF THE NORTHERN RED
RIVER VALLEY AND THE DEVILS LAKE BASIN. HOWEVER...SOUTHERN LOCATIONS
ARE STILL SOCKED IN AND WINDS ARE FROM THE SOUTH...AND MORE STRATUS
IS OUT OVER WESTERN PORTIONS OF THE CWA. GFS AND SREF PROBABILITIES
ARE NOT HANDLING THE CURRENT LOW CLOUDS VERY WELL SO WILL DISREGARD
THOSE SOLUTIONS. THE NAM...HRRR...AND RAP ARE MUCH MORE PESSIMISTIC
FOR CIGS SO WILL LEAN IN THAT DIRECTION. THINK THAT THE SOUTHERN AND
EASTERN SPOTS THAT ARE STILL IFR WILL SEE SOME IMPROVEMENT TO MVFR
FOR A BRIEF PERIOD THIS AFTERNOON...BUT THEN GO BACK INTO THE SOUP
TONIGHT. THINK THERE SHOULD BE QUITE A LOT OF IFR CIGS...AND SOME
GUIDANCE IS PUTTING IN SOME VIS IN THE 3 TO 5SM RANGE...BUT WILL
JUST KEEP CIGS LOW FOR NOW AND ADD ANY VIS RESTRICTIONS LATER. WILL
CONTINUE TO KEEP STRATUS LINGERING OVER THE AREA THROUGH THE END OF
THE PERIOD AS THERE WILL BE SOUTH TO SOUTHEAST WINDS AT 10 TO 15 KTS
THAT WILL HAVE A TOUGH TIME SCOURING OUT CLOUDS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JK
SHORT TERM...GODON
LONG TERM...GODON/TG
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1151 PM CST MON DEC 8 2014
.UPDATE...
ISSUED AT 1150 PM CST MON DEC 8 2014
FAIR AMOUNT OF LOW CLOUDS WERE ACROSS THE AREA AND LOW CLOUDS
CONTINUE TO MOVE IN FROM SOUTHERN ONTARIO. CLOUD DECK EXTENDS INTO
SOUTHERN MN AND INTO IA AND MAY KEEP AREA CLOUDY THROUGH TUE MORN.
SURFACE HIGH PRESSURE WAS LOCATED OVER NORTHEAST ND BETWEEN RUGBY
AND CANDO. THE HIGH PRESSURE SYSTEM WILL MOVE TO THE WESTERN GREAT
LAKES BY TUE AFTERNOON. NO CHANGE TO THE OVERNIGHT LOW TEMP.
UPDATE ISSUED AT 1000 PM CST MON DEC 8 2014
LOW LEVEL TRAJECTORY IS FROM THE NORTH/NORTHEAST. FOG LOOP INDICATED
CLOUDS OVER SOUTHERN ONTARIO CONTINUE TO ADVECT TO THE SOUTHWEST.
WILL HAVE TO RAISE TEMPS OVER THE MN SIDE WITH MORE CLOUDS FOR THE
REST OF THE NIGHT AND DECREASE OVER PARTS OF EASTERN ND.
UPDATE ISSUED AT 700 PM CST MON DEC 8 2014
SURFACE HIGH PRESSURE WAS LOCATED OVER THE CENTRAL DAKOTAS. WINDS
WERE DROPPING OFF OVER EASTERN NORTH DAKOTA WITH LOSS OF INSOLATION.
EXPECT TEMPS IN THE NORTHWEST ZONES TO DROP OFF QUICKLY THIS EVENING
WITH NO CLOUD COVER.
HOURLY TEMPS TWEAKED THIS EVENING WITH CLEARING MOVING IN FROM THE
NORTHWEST. LOW TEMPS DECREASED A BIT WITH CLEARING IN THE NORTH.
WILL UPDATE LOW TEMP ON NEXT UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 335 PM CST MON DEC 8 2014
CLOUD COVER TRENDS AND IF WE GET ANY FOG DEVELOPMENT TONIGHT ARE
THE MAIN FORECAST CONCERNS.
NORTHWESTERLY FLOW ALOFT CONTINUES AS THE UPPER TROUGH DIGS INTO
THE GREAT LAKES. THE SFC LOW HAS BEEN MOVING OFF OF THE ARROWHEAD
OF MN AND WILL CONTINUE TO HEAD EAST...ALLOWING HIGH PRESSURE TO
BUILD IN FROM ONTARIO INTO THE NORTHERN PLAINS TONIGHT. SOME
BREAKS IN THE CLOUDS HAVE STARTED IN THE NORTHERN AND WESTERN
CWA...WHICH THE RAP HAS A DECENT HANDLE ON. CLOUDS SHOULD
GRADUALLY CLEAR FROM NORTH TO SOUTH THIS EVENING...AND WE SHOULD
BE FAIRLY CLEAR BY MORNING. TEMPS WILL DROP INTO THE SINGLE
DIGITS...AND WINDS SHOULD BECOME FAIRLY LIGHT AS THE CENTER OF THE
HIGH MOVES OVER THE AREA. THE RAP AND HRRR HAVE SIGNS OF SOME
PATCHY FOG FORMATION...BUT ALONG WITH THE LIGHT WINDS AND CLEAR
SKIES WILL BE DRIER AIR AT THE SFC. THINK THAT CHANCES WILL NOT BE
HIGH ENOUGH FOR FOG TO INCLUDE IN THE GRIDS AT THIS POINT...BUT
WILL KEEP AN EYE ON IT.
TOMORROW...AN EMBEDDED SHORTWAVE WILL MOVE INTO SD...BUT
THE COLUMN WILL BE TOO DRY TO DO MUCH AND NONE OF THE MODELS ARE
PRODUCING ANY PRECIP. THE SFC HIGH WILL BEGIN TO MOVE OFF TO THE
EAST...AND RETURN FLOW WILL SET UP BY MORNING AND CONTINUE
THROUGHOUT THE DAY ON TUESDAY. WITH A COLD START AND 850MB TEMPS
STILL CLOSE TO ZERO EARLY IN THE DAY...TEMPS WILL STAY IN THE 20S
EVEN WITH WARM AIR ADVECTION. THE SOUTH WINDS AND WARM ADVECTION
WILL CONTINUE INTO TUESDAY NIGHT AS UPPER RIDGING BUILDS INTO THE
REGION. THERE SHOULD BE ENOUGH MIXING TO KEEP LOWS IN THE TEENS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 PM CST MON DEC 8 2014
WEDNESDAY THROUGH THURSDAY...UPPER RIDGING WILL CONTINUE TO BUILD
ACROSS THE NORTHERN PLAINS. SOUTHERN WINDS WILL CONTINUE AS THE
SFC TROUGH REMAINS TO OUR NORTHWEST...BRINGING 850MB TEMPS BACK UP
WELL ABOVE ZERO AND SOME CLOSE TO 10 C. THE SPOILER MAY BE IF WE
GET STRATUS COMING BACK UP AND REMAINING OVER THE REGION. THE NAM
WAS EVEN TRYING TO PUT SOME VERY LIGHT PRECIP OUT THURSDAY OVER
THE EASTERN COUNTIES. WILL LEAVE ANY DRIZZLE MENTION OUT FOR NOW
BUT BUMPED UP CLOUDS A BIT IN THE FAR EAST. HIGHS SHOULD SLOWLY
BECOME WARMER THROUGH WEDNESDAY AND THURSDAY...REACHING BACK
TOWARDS THE 30 MARK AND THEN INTO THE MID AND UPPER 30S ON
THURSDAY.
THURSDAY NIGHT TO MONDAY...MODELS CONTINUE TO AGREE ON 500MB RIDGING
ACROSS THE NORTHERN PLAINS FOR THE END OF THE WEEK. NAEFS SHOWS
850MB TEMPS RANGING FROM 2 TO 3 STANDARD DEVIATIONS ABOVE NORMAL
STARTING EARLY FRIDAY THROUGH LATE SATURDAY...AS 850MB TEMPS REACH
TO 12C TO 16C FRIDAY NIGHT. MODELS INDICATE WINDS FROM THE SOUTH
INSTEAD OF THE SFC WARMING SW OR WEST PLUS THE POTENTIAL FOR LOW
STRATUS LAYER ADVECTING NORTH KEEPING TEMPS COOLER SATURDAY. FOR NOW
WILL CONTINUE WITH A BLEND AS CLOUDS WILL MAKE OR BREAK TEMPS...EVEN
WITH LOW SUN ANGLE. UPR 30S TO 40 WITH CLOUDS...WITHOUT MID TO UPR
40S POSSIBLE FRIDAY AND SATURDAY. FROPA SUNDAY WILL BRING LIGHT PCPN
CHC TO THE FA AND BRING TEMPS DOWN TO NEAR NORMAL WITH HIGHS IN THE
LOW 20S BY MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1150 PM CST MON DEC 8 2014
IFR TO MVFR CIGS OF 7 TO 16 HUNDRED FT WERE ACROSS THE FORECAST
AREA. LOW LEVEL WINDS WILL BECOME SOUTHEAST BY TUE MORN AND LIKELY
ADVECT LOW LEVEL MOISTURE BACK INTO THE AREA. WILL KEEP IFR/MVFR
CIGS THROUGH TUE MORN AND MAY LAST INTO TUE AFTERNOON IN NORTHWEST
MN. EXPECT CIGS TO RISE INTO THE MVFR CATEGORY BY LATE TUE MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...HOPPES
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1143 PM EST MON DEC 8 2014
.SYNOPSIS...
A WEAKENING LOW NEAR LAKE SUPERIOR WILL DROP SOUTHEAST THROUGH THE
AREA TONIGHT TO MERGE WITH A LOW NEAR THE VIRGINIA COAST TUESDAY
MORNING THAT WILL STALL NEAR BOSTON THROUGH THURSDAY. HIGH PRESSURE
OVER THE UPPER MIDWEST WEDNESDAY WILL EVENTUALLY SPREAD UP THE OHIO
VALLEY BY THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
LATEST HRRR MODEL RIGHT ON TARGET WITH PRECIPITATION EXPANDING
NORTH INTO THE CENTRAL PORTIONS OF THE FORECAST AREA. MADE SOME
ADJUSTMENTS TO PRECIPITATION TO ACCOUNT FOR THIS ACTIVITY. COLDER
AIR PUSHING EAST WITH THE COLD FRONT OVERNIGHT AND WILL CHANGE
PRECIPITATION OVER TO SNOW FROM WEST TO EAST. TEMPERATURES STILL
LOOK REASONABLE AS DEW POINTS ARE CURRENTLY IN THE MIDDLE THIRTIES
BEHIND THE WEAK WARM FRONT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
THE SITUATION ON TUE LOOKS SIMILAR TO THE LATTER PART OF TONIGHT
WITH TEMPS NOT QUITE COLD ENOUGH TO SUPPORT JUST SNOW. CAN SEE THE
PRECIP WAVERING BACK AND FORTH ON TUE. BESIDES...THE PRECIP WILL BE
LIGHT SO THINK SNOW ACCUMULATION WILL STAY UNDER A HALF AN INCH.
BY TUE NIGHT...THE BETTER ENERGY AND DEEPER MOISTURE WILL BE
SHIFTING EAST TOWARD THE EAST COAST SYSTEM. TEMPS SHOULD BE GETTING
COLD ENOUGH FOR JUST SNOW BUT THE THREAT SHOULD BE SHIFTING INTO
MAINLY JUST THE SNOWBELT. TEMPS ALOFT ONLY GET COLD ENOUGH FOR A
LITTLE LAKE ENHANCEMENT. SNOW ACCUMULATION WILL MAINLY BE IN THE
SNOWBELT AND NEARBY AREAS WITH MAX AMOUNTS OF ABOUT 2 TO MAYBE 3
INCHES LOOKING POSSIBLE IN THE FAVORED AREAS OF THE SNOWBELT IN NW
PA.
THE WEATHER PATTERN WILL REMAIN NEARLY STALLED INTO THU SO NOT A LOT
WILL CHANGE THRU THEN. A GOOD CHANCE FOR LAKE ENHANCED SNOW SHOWERS
WILL PREVAIL THRU THU WITH ACCUMULATION AMOUNTS GENERALLY STAYING ON
THE LIGHTER SIDE WITH ABOUT 1 TO 3 INCHES POSSIBLE IN ANY GIVEN 12
HOUR PERIOD IN THE SNOWBELT WITH DUSTINGS OF ACCUMULATION POSSIBLE
IN NEARBY AREAS.
TEMPS WILL STAY ABOUT 5 DEGREE BELOW NORMAL THRU THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
GENERALLY DRY WITH A WARMING TREND FOR THIS PERIOD.
THE SURFACE RIDGE AND UPPER RIDGE WILL BE BUILDING IN ACROSS THE
AREA STARTING FRIDAY AND IT WILL MOVE EAST OF THE AREA BY MONDAY.
ON FRIDAY A WEAK SURFACE TROF WILL BRUSH THE EASTERN PORTION OF THE
FORECAST AREA. KEPT SLIGHT CHANCE POPS WITH A THREAT OF FLURRIES AND
POSSIBLY SPRINKLES IN THE AFTERNOON EAST OF CLEVELAND. THE 12Z
ECMWF IS A LITTLE MORE PESSIMISTIC IN CONTINUING SOME QPF ON FRIDAY
AS IT IS A LITTLE SLOWER IN MOVING IN THE RIDGE. AT THIS TIME
LEANING MAINLY DRY.
THE ECMWF MODEL WAS TRYING TO HINT AT SOME QPF OVER THE WEEKEND.
THIS DOES NOT SEEM REASONABLE BASED ON THE DRY AIR...RIDGING AND NO
OMEGA. THE GFS AND CANADIAN MODEL KEEPS IT DRY...SO WENT THAT
DIRECTION.
WENT CLOSE TO WPC GUIDANCE FOR THE TEMPERATURES. TEMPERATURES WILL
BECOME ABOVE NORMAL BY SUNDAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
IFR CEILINGS ARE MOVING INTO NW OHIO AND WILL CONTINUE TO MOVE
EASTWARD WITH A WEAKENING COLD FRONT. THERE IS SOME VERY LIGHT
RAIN/DRIZZLE OVER A LARGE PORTION OF THE AREA AND EXPECT THIS TO
CONTINUE THROUGH MUCH OF THE OVERNIGHT HOURS. THE KERI AREA WILL
LIKELY BE THE LATEST GETTING THE IFR CONDITIONS SINCE THERE WILL
BE A DECENT DOWNSLOPING COMPONENT THROUGH THE NIGHT.
A SECONDARY SURGE OF COOLER AIR WILL ARRIVE BY EARLY TUESDAY
AFTERNOON AS THE UPPER LEVEL TROUGH PASSES. WINDS WILL SHIFT
AROUND TO THE NORTH AS IT PASSES. SOME LIGHT RAIN MAY DEVELOP WITH
THE UPPER LEVEL TROUGH. TIMING AND INTENSITY IS UNCERTAIN SO ONLY
PLACED A VICINITY SHOWER IN THE TAFS AT THIS POINT. WILL HAVE TO
MONITOR FOR A CHANGE TO SNOW BY TUESDAY EVENING...ESPECIALLY NE
OHIO INTO NW PA.
.OUTLOOK...NON VFR MAINLY IN NE OHIO AND NW PA TUESDAY NIGHT INTO
THUR WITH LINGERING SNOW SHOWERS.
&&
.MARINE...
.SYNOPSIS...
A WEAKENING LOW NEAR LAKE SUPERIOR WILL DROP SOUTHEAST THROUGH THE
AREA TONIGHT TO MERGE WITH A LOW NEAR THE VIRGINIA COAST TUESDAY
MORNING THAT WILL STALL NEAR BOSTON THROUGH THURSDAY. HIGH PRESSURE
OVER THE UPPER MIDWEST WEDNESDAY WILL EVENTUALLY SPREAD UP THE OHIO
VALLEY BY THE WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ADAMS
NEAR TERM...LOMBARDY
SHORT TERM...ADAMS
LONG TERM...KIELTYKA
AVIATION...MULLEN
MARINE...MAYERS
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
932 PM CST WED DEC 10 2014
.UPDATE...
ADDED SPRINKLE WORDING TO ALL BUT FAR WESTERN OKLAHOMA AND
WESTERN NORTH TEXAS AS WEAK NWLY MID-LEVEL WAVE APPROACHES.
RAINFALL EXPECTED TO REMAIN VERY LIGHT AND BRIEF. AREAS OF FOG
EXPECTED ONCE AGAIN...WITH SOME DENSE FOG POSSIBLE OVER FAR
NORTHWEST OKLAHOMA. WITH STRATUS ENTRENCHED ACROSS THE
REGION...WILL BE HARDER FOR DENSE FOG TO DEVELOP BUT NOT OUT OF
THE QUESTION.
&&
.PREV DISCUSSION... /ISSUED 539 PM CST WED DEC 10 2014/
AVIATION...
AREAS OF LOW CLOUDS AND FOG WILL AGAIN BE ISSUES WITH THIS SET OF
TAFS. THE HRRR.. RAP AND SREF ARE NOT NEARLY AS BULLISH TODAY WITH
THE DENSE FOG ACROSS THE AREA AS RECENT NIGHTS BUT HIGHLIGHT THE
AREAS OF NORTHWEST OKLAHOMA /SPECIFICALLY KWWR AND POTENTIALLY
KGAG/ WITH THE HIGHEST CHANCE OF DENSE FOG. BUT THE MOS FROM THE
SYNOPTIC MODELS HIT THE FOG POSSIBILITY A LITTLE HIGHER THAN
RECENT NIGHTS. WILL CONFINE THE MENTION OF FG TO KGAG AND KWWR BUT
KEEP A TEMPO GROUP OF 1SM BR IN SOME OF THE OTHER TAF SITES.
REGARDLESS... CEILINGS WILL BE TRENDING DOWN THROUGHOUT THE AREA
OVERNIGHT SO EXPECT WIDESPREAD MVFR CONDITIONS WITH AREAS OF IFR.
THE CEILINGS WILL LIKELY LINGER INTO THE DAY THURSDAY AS LOW LEVEL
HUMIDITY INCREASES.
PREV DISCUSSION... /ISSUED 227 PM CST WED DEC 10 2014/
DISCUSSION...
FOR TONIGHT...AREAS OF DENSE FOG MAY DEVELOP...ESPECIALLY ACROSS
NORTHWEST OKLAHOMA IF CLOUDS CAN CLEAR SOME JUST BEFORE SUNSET.
OTHERWISE...WILL KEEP IN A CHANCE OF DRIZZLE OVER NORTH CENTRAL
OKLAHOMA...WHERE WEAK ASCENT AND HIGHER HUMIDITY WILL OCCUR
THROUGH AT LEAST MIDNIGHT.
LOW CLOUDS AND AREAS OF FOG WILL RETURN THURSDAY NIGHT INTO FRIDAY
AS MOISTURE OVER SOUTH TEXAS GRADUALLY INCREASES. ISENTROPIC
ASCENT WILL REMAIN WEAK...BUT SOUTH CENTRAL AND SOUTHEAST OKLAHOMA
WILL HAVE THE BEST OPPORTUNITY FOR VERY LIGHT RAIN SHOWERS OR
DRIZZLE.
SOUTHERLY WINDS WILL BEGIN TO INCREASE LATE FRIDAY INTO SATURDAY
AS A STRONG SYSTEM MOVES ACROSS CALIFORNIA. MODELS ARE SIMILAR IN
TRACKING THIS SYSTEM ACROSS NORTHERN OKLAHOMA/KANSAS ON SUNDAY.
THIS TRACK WILL BRING DRIER MID AND UPPER LEVEL AIR INTO SOUTHWEST
OKLAHOMA AND NORTH TEXAS AND LIMIT THE AMOUNT OF RAIN. STRONG
SOUTHWEST WINDS WILL ALSO DEVELOP GIVEN THE TIMING OF THE GFS.
ALTHOUGH WIND SHEAR WILL BECOME RATHER STRONG WITH THIS
SYSTEM...INSTABILITY IS EXPECTED TO REMAIN WEAK.
COLDER AND DRIER WEATHER CAN BE EXPECTED MONDAY INTO TUESDAY WITH
STRONG NORTHERLY WINDS MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 44 59 49 62 / 10 10 20 10
HOBART OK 45 60 49 64 / 10 10 10 10
WICHITA FALLS TX 46 64 51 68 / 10 10 10 10
GAGE OK 40 60 44 65 / 10 0 10 10
PONCA CITY OK 40 55 45 59 / 10 10 10 10
DURANT OK 44 55 48 64 / 10 20 30 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
11/26
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
539 PM CST WED DEC 10 2014
.AVIATION...
AREAS OF LOW CLOUDS AND FOG WILL AGAIN BE ISSUES WITH THIS SET OF
TAFS. THE HRRR.. RAP AND SREF ARE NOT NEARLY AS BULLISH TODAY WITH
THE DENSE FOG ACROSS THE AREA AS RECENT NIGHTS BUT HIGHLIGHT THE
AREAS OF NORTHWEST OKLAHOMA /SPECIFICALLY KWWR AND POTENTIALLY
KGAG/ WITH THE HIGHEST CHANCE OF DENSE FOG. BUT THE MOS FROM THE
SYNOPTIC MODELS HIT THE FOG POSSIBILITY A LITTLE HIGHER THAN
RECENT NIGHTS. WILL CONFINE THE MENTION OF FG TO KGAG AND KWWR BUT
KEEP A TEMPO GROUP OF 1SM BR IN SOME OF THE OTHER TAF SITES.
REGARDLESS... CEILINGS WILL BE TRENDING DOWN THROUGHOUT THE AREA
OVERNIGHT SO EXPECT WIDESPREAD MVFR CONDITIONS WITH AREAS OF IFR.
THE CEILINGS WILL LIKELY LINGER INTO THE DAY THURSDAY AS LOW LEVEL
HUMIDITY INCREASES.
&&
.PREV DISCUSSION... /ISSUED 227 PM CST WED DEC 10 2014/
DISCUSSION...
FOR TONIGHT...AREAS OF DENSE FOG MAY DEVELOP...ESPECIALLY ACROSS
NORTHWEST OKLAHOMA IF CLOUDS CAN CLEAR SOME JUST BEFORE SUNSET.
OTHERWISE...WILL KEEP IN A CHANCE OF DRIZZLE OVER NORTH CENTRAL
OKLAHOMA...WHERE WEAK ASCENT AND HIGHER HUMIDITY WILL OCCUR
THROUGH AT LEAST MIDNIGHT.
LOW CLOUDS AND AREAS OF FOG WILL RETURN THURSDAY NIGHT INTO FRIDAY
AS MOISTURE OVER SOUTH TEXAS GRADUALLY INCREASES. ISENTROPIC
ASCENT WILL REMAIN WEAK...BUT SOUTH CENTRAL AND SOUTHEAST OKLAHOMA
WILL HAVE THE BEST OPPORTUNITY FOR VERY LIGHT RAIN SHOWERS OR
DRIZZLE.
SOUTHERLY WINDS WILL BEGIN TO INCREASE LATE FRIDAY INTO SATURDAY
AS A STRONG SYSTEM MOVES ACROSS CALIFORNIA. MODELS ARE SIMILAR IN
TRACKING THIS SYSTEM ACROSS NORTHERN OKLAHOMA/KANSAS ON SUNDAY.
THIS TRACK WILL BRING DRIER MID AND UPPER LEVEL AIR INTO SOUTHWEST
OKLAHOMA AND NORTH TEXAS AND LIMIT THE AMOUNT OF RAIN. STRONG
SOUTHWEST WINDS WILL ALSO DEVELOP GIVEN THE TIMING OF THE GFS.
ALTHOUGH WIND SHEAR WILL BECOME RATHER STRONG WITH THIS
SYSTEM...INSTABILITY IS EXPECTED TO REMAIN WEAK.
COLDER AND DRIER WEATHER CAN BE EXPECTED MONDAY INTO TUESDAY WITH
STRONG NORTHERLY WINDS MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 45 59 49 62 / 10 10 20 10
HOBART OK 45 60 49 64 / 10 10 10 10
WICHITA FALLS TX 46 64 51 68 / 10 10 10 10
GAGE OK 41 60 44 65 / 10 0 10 10
PONCA CITY OK 42 55 45 59 / 10 10 10 10
DURANT OK 43 55 48 64 / 10 20 30 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1209 PM CST TUE DEC 9 2014
.DISCUSSION...
SEE AVIATION
&&
.AVIATION...
DENSE FOG ACROSS TERMINAL KSPS IS EXPECTED TO LIFT BY 20Z...AS A
WEAK COLD FRONT CONTINUES TO PUSH THROUGH. OTHERWISE ALL OTHER
TERMINALS SHOULD REMAIN UNDER VFR CONDITIONS THROUGH THE DAY. FOG
MAY REDEVELOP BY 10Z TONIGHT ACROSS MOST TERMINALS. IT IS POSSIBLE
THAT THE FOG COULD BECOME DENSE...ESPECIALLY SOUTH OF I-40.
&&
.PREV DISCUSSION... /ISSUED 1030 AM CST TUE DEC 9 2014/
DISCUSSION...
FOG HAS PERSISTED LONGER THAN ORIGINALLY ANTICIPATED NEAR THE RED
RIVER. WE STILL EXPECT IMPROVEMENT TO BEGIN WITHIN THE HOUR...AND
DENSE FOG SHOULD BE GONE FROM MOST OF OUR FORECAST AREA BY 11 AM.
THE DENSE FOG ADVISORY WAS EXTENDED UNTIL 11 AM.
THE REST OF THE FORECAST APPEARS TO BE IN GOOD SHAPE...AND NO
OTHER CHANGES ARE PLANNED FOR THIS MORNING.
PREV DISCUSSION... /ISSUED 531 AM CST TUE DEC 9 2014/
AVIATION...12Z TAF ISSUANCE...
IFR VISIBILITIES WILL PERSIST FOR AIRFIELDS ACROSS PORTIONS OF
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THROUGH MID TO LATE
MORNING AS AREAS OF DENSE FOG REMAIN SPREAD ACROSS THE REGION.
VISIBILITIES ARE EXPECTED TO IMPROVE THROUGH NOON... WITH WINDS
CONTINUING TO BACK TO THE EAST/SOUTHEAST THROUGH THE AFTN.
OVERNIGHT... LIGHT FOG MAY IMPACT VARIOUS SITES ACROSS PORTIONS OF
CENTRAL AND SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS ONCE AGAIN.
VISIBILITIES WILL LIKELY LINGER BETWEEN MVFR AND VFR... HOWEVER...
A POCKETS OF IFR WILL BE POSSIBLE.
JTK
PREV DISCUSSION... /ISSUED 258 AM CST TUE DEC 9 2014/
DISCUSSION...
IN RESPONSE TO VERY SHALLOW SFC MOISTURE ACROSS TEXOMA AND THE RED
RIVER VALLEY... DENSE FOG WILL REMAIN IN PLACE ACROSS SRN OK AND WRN
N TX. RECENT RAP AND HRRR OUTPUT OF VIS AND BOUNDARY LAYER RH VALUES
HINT AT FOG EXPANSION NORTHWARD INTO CENTRAL OK FOR AN HOUR OR TWO
NEAR SUNRISE BEFORE CONDITIONS IMPROVE THROUGH THE MID TO LATE
MORNING HOURS. IN RESPONSE TO THIS... HAVE MADE THE DECISION TO
EXTEND THE CURRENT DENSE FOG ADVISORY THROUGH 16Z (10AM CST). AT THE
MOMENT... NOT CONVINCED OF WIDESPREAD DENSE FOG REACHING FARTHER
NORTH THAN THE CURRENT ADVISORY. HOWEVER... SOME POCKETS OF SHORT
DURATION DENSE FOG WILL BE POSSIBLE OUTSIDE THE ADVISORY. WITH THAT
IN MIND... AND GIVEN THE CURRENT VIS TRENDS THROUGH 230AM CST...
THERE ARE NO PLANS TO EXPAND THE ADVISORY FARTHER NORTH AT THE
MOMENT. WE WILL CONTINUE TO WATCH VIS TRENDS CLOSELY THIS MORNING IN
THE EVENT AN EXPANSION IS NECESSARY.
FOR THE REST OF TODAY... HELPING CLEAR FOG SOUTHWARD THROUGH THE
MORNING WILL BE ANOTHER WEAK SFC BOUNDARY... MUCH LIKE THE ONE
YESTERDAY. WINDS WILL SLOWLY BACK TO THE EAST ACROSS NRN AND CENTRAL
OK THROUGH THE AFTN. TEMPS WILL CLIMB INTO THE 50S FOR HIGHS.
OVERNIGHT... AS THE H500 RIDGE BROADENS ACROSS THE WRN U.S... A WEAK
H500 SHORT WAVE TROUGH WILL CONTINUE TO APPROACH FROM THE WEST
ACROSS ERN NM AND WEST TX. THIS WILL OPEN UP SOME MODEST SFC
MOISTURE RETURN FROM THE GULF. PAIRED WITH SOME WEAK LL ISENTROPIC
ASCENT AS THE TROUGH SWINGS THROUGH... SOME LIGHT SHOWERS/DRIZZLE
MAY DEVELOP ACROSS THE RED RIVER VALLEY LATE WED INTO THU.
SLIGHT CHANCES FOR SHOWERS AND DRIZZLE ACROSS PORTIONS OF SOUTHERN
AND CENTRAL OK WILL CONTINUE THROUGH FRI AS THE RIDGE OVER THE
MIDWEST STRENGTHENS... LEAVING THE SRN PLAINS WITHIN THE WARM SECTOR
AND CONTINUAL SFC MOISTURE RETURN. OVERALL... MOST WILL REMAIN
DRY... WITH MILD TEMPERATURES CONTINUING.
FOR THE WEEKEND... LONG RANGE GUIDANCE... GFS/GFS13KM/ECMWF/CA...
HAVE CONTINUED TO SHOW DECENT CONTINUITY OVER THE PAST COUPLE RUNS
WITH RESPECT TO THE DEEP H500 TROUGH MOVING INTO THE PLAINS SAT.
INCREASED PRECIP CHCS SAT NIGHT INTO SUN. EXPECT SOME RUMBLES OF
THUNDER ON SUNDAY. A DECENT LOW... BUFR SOUNDINGS FROM KSPS TO KOUN
SHOW COLD TEMPS ALOFT... ENOUGH FOR SOME MINOR ELEVATED INSTABILITY
SUPPORTIVE OF SOME ISOLATED THUNDER WITHIN THE RAIN SHOWERS THAT
DEVELOP. NOT EXPECTING ANY SIGNIFICANT WEATHER... BUT THE POTENTIAL
FOR SOME WELCOME RAINFALL ACROSS THE REGION.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 55 36 55 45 / 0 0 10 10
HOBART OK 57 40 55 46 / 0 0 10 10
WICHITA FALLS TX 58 42 58 48 / 0 0 10 20
GAGE OK 54 37 54 42 / 0 0 10 10
PONCA CITY OK 48 32 50 42 / 0 0 10 20
DURANT OK 60 40 55 45 / 0 0 0 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
23/03/67
AREA FORECAST DISCUSSION
NWS NORMAN OK
1030 AM CST TUE DEC 9 2014
.DISCUSSION...
FOG HAS PERSISTED LONGER THAN ORIGINALLY ANTICIPATED NEAR THE RED
RIVER. WE STILL EXPECT IMPROVEMENT TO BEGIN WITHIN THE HOUR...AND
DENSE FOG SHOULD BE GONE FROM MOST OF OUR FORECAST AREA BY 11 AM.
THE DENSE FOG ADVISORY WAS EXTENDED UNTIL 11 AM.
THE REST OF THE FORECAST APPEARS TO BE IN GOOD SHAPE...AND NO
OTHER CHANGES ARE PLANNED FOR THIS MORNING.
&&
.PREV DISCUSSION... /ISSUED 531 AM CST TUE DEC 9 2014/
AVIATION...12Z TAF ISSUANCE...
IFR VISIBILITIES WILL PERSIST FOR AIRFIELDS ACROSS PORTIONS OF
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THROUGH MID TO LATE
MORNING AS AREAS OF DENSE FOG REMAIN SPREAD ACROSS THE REGION.
VISIBILITIES ARE EXPECTED TO IMPROVE THROUGH NOON... WITH WINDS
CONTINUING TO BACK TO THE EAST/SOUTHEAST THROUGH THE AFTN.
OVERNIGHT... LIGHT FOG MAY IMPACT VARIOUS SITES ACROSS PORTIONS OF
CENTRAL AND SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS ONCE AGAIN.
VISIBILITIES WILL LIKELY LINGER BETWEEN MVFR AND VFR... HOWEVER...
A POCKETS OF IFR WILL BE POSSIBLE.
JTK
PREV DISCUSSION... /ISSUED 258 AM CST TUE DEC 9 2014/
DISCUSSION...
IN RESPONSE TO VERY SHALLOW SFC MOISTURE ACROSS TEXOMA AND THE RED
RIVER VALLEY... DENSE FOG WILL REMAIN IN PLACE ACROSS SRN OK AND WRN
N TX. RECENT RAP AND HRRR OUTPUT OF VIS AND BOUNDARY LAYER RH VALUES
HINT AT FOG EXPANSION NORTHWARD INTO CENTRAL OK FOR AN HOUR OR TWO
NEAR SUNRISE BEFORE CONDITIONS IMPROVE THROUGH THE MID TO LATE
MORNING HOURS. IN RESPONSE TO THIS... HAVE MADE THE DECISION TO
EXTEND THE CURRENT DENSE FOG ADVISORY THROUGH 16Z (10AM CST). AT THE
MOMENT... NOT CONVINCED OF WIDESPREAD DENSE FOG REACHING FARTHER
NORTH THAN THE CURRENT ADVISORY. HOWEVER... SOME POCKETS OF SHORT
DURATION DENSE FOG WILL BE POSSIBLE OUTSIDE THE ADVISORY. WITH THAT
IN MIND... AND GIVEN THE CURRENT VIS TRENDS THROUGH 230AM CST...
THERE ARE NO PLANS TO EXPAND THE ADVISORY FARTHER NORTH AT THE
MOMENT. WE WILL CONTINUE TO WATCH VIS TRENDS CLOSELY THIS MORNING IN
THE EVENT AN EXPANSION IS NECESSARY.
FOR THE REST OF TODAY... HELPING CLEAR FOG SOUTHWARD THROUGH THE
MORNING WILL BE ANOTHER WEAK SFC BOUNDARY... MUCH LIKE THE ONE
YESTERDAY. WINDS WILL SLOWLY BACK TO THE EAST ACROSS NRN AND CENTRAL
OK THROUGH THE AFTN. TEMPS WILL CLIMB INTO THE 50S FOR HIGHS.
OVERNIGHT... AS THE H500 RIDGE BROADENS ACROSS THE WRN U.S... A WEAK
H500 SHORT WAVE TROUGH WILL CONTINUE TO APPROACH FROM THE WEST
ACROSS ERN NM AND WEST TX. THIS WILL OPEN UP SOME MODEST SFC
MOISTURE RETURN FROM THE GULF. PAIRED WITH SOME WEAK LL ISENTROPIC
ASCENT AS THE TROUGH SWINGS THROUGH... SOME LIGHT SHOWERS/DRIZZLE
MAY DEVELOP ACROSS THE RED RIVER VALLEY LATE WED INTO THU.
SLIGHT CHANCES FOR SHOWERS AND DRIZZLE ACROSS PORTIONS OF SOUTHERN
AND CENTRAL OK WILL CONTINUE THROUGH FRI AS THE RIDGE OVER THE
MIDWEST STRENGTHENS... LEAVING THE SRN PLAINS WITHIN THE WARM SECTOR
AND CONTINUAL SFC MOISTURE RETURN. OVERALL... MOST WILL REMAIN
DRY... WITH MILD TEMPERATURES CONTINUING.
FOR THE WEEKEND... LONG RANGE GUIDANCE... GFS/GFS13KM/ECMWF/CA...
HAVE CONTINUED TO SHOW DECENT CONTINUITY OVER THE PAST COUPLE RUNS
WITH RESPECT TO THE DEEP H500 TROUGH MOVING INTO THE PLAINS SAT.
INCREASED PRECIP CHCS SAT NIGHT INTO SUN. EXPECT SOME RUMBLES OF
THUNDER ON SUNDAY. A DECENT LOW... BUFR SOUNDINGS FROM KSPS TO KOUN
SHOW COLD TEMPS ALOFT... ENOUGH FOR SOME MINOR ELEVATED INSTABILITY
SUPPORTIVE OF SOME ISOLATED THUNDER WITHIN THE RAIN SHOWERS THAT
DEVELOP. NOT EXPECTING ANY SIGNIFICANT WEATHER... BUT THE POTENTIAL
FOR SOME WELCOME RAINFALL ACROSS THE REGION.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 55 36 55 45 / 0 0 10 10
HOBART OK 57 40 55 46 / 0 0 10 10
WICHITA FALLS TX 58 42 58 48 / 0 0 10 20
GAGE OK 54 37 54 42 / 0 0 10 10
PONCA CITY OK 48 32 50 42 / 0 0 10 20
DURANT OK 60 40 55 45 / 0 0 0 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR OKZ033>048-
050>052.
TX...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR TXZ083>090.
&&
$$
23/03
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
531 AM CST TUE DEC 9 2014
.AVIATION...12Z TAF ISSUANCE...
IFR VISIBILITIES WILL PERSIST FOR AIRFIELDS ACROSS PORTIONS OF
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THROUGH MID TO LATE
MORNING AS AREAS OF DENSE FOG REMAIN SPREAD ACROSS THE REGION.
VISIBILITIES ARE EXPECTED TO IMPROVE THROUGH NOON... WITH WINDS
CONTINUING TO BACK TO THE EAST/SOUTHEAST THROUGH THE AFTN.
OVERNIGHT... LIGHT FOG MAY IMPACT VARIOUS SITES ACROSS PORTIONS OF
CENTRAL AND SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS ONCE AGAIN.
VISIBILITIES WILL LIKELY LINGER BETWEEN MVFR AND VFR... HOWEVER...
A POCKETS OF IFR WILL BE POSSIBLE.
JTK
&&
.PREV DISCUSSION... /ISSUED 258 AM CST TUE DEC 9 2014/
DISCUSSION...
IN RESPONSE TO VERY SHALLOW SFC MOISTURE ACROSS TEXOMA AND THE RED
RIVER VALLEY... DENSE FOG WILL REMAIN IN PLACE ACROSS SRN OK AND WRN
N TX. RECENT RAP AND HRRR OUTPUT OF VIS AND BOUNDARY LAYER RH VALUES
HINT AT FOG EXPANSION NORTHWARD INTO CENTRAL OK FOR AN HOUR OR TWO
NEAR SUNRISE BEFORE CONDITIONS IMPROVE THROUGH THE MID TO LATE
MORNING HOURS. IN RESPONSE TO THIS... HAVE MADE THE DECISION TO
EXTEND THE CURRENT DENSE FOG ADVISORY THROUGH 16Z (10AM CST). AT THE
MOMENT... NOT CONVINCED OF WIDESPREAD DENSE FOG REACHING FARTHER
NORTH THAN THE CURRENT ADVISORY. HOWEVER... SOME POCKETS OF SHORT
DURATION DENSE FOG WILL BE POSSIBLE OUTSIDE THE ADVISORY. WITH THAT
IN MIND... AND GIVEN THE CURRENT VIS TRENDS THROUGH 230AM CST...
THERE ARE NO PLANS TO EXPAND THE ADVISORY FARTHER NORTH AT THE
MOMENT. WE WILL CONTINUE TO WATCH VIS TRENDS CLOSELY THIS MORNING IN
THE EVENT AN EXPANSION IS NECESSARY.
FOR THE REST OF TODAY... HELPING CLEAR FOG SOUTHWARD THROUGH THE
MORNING WILL BE ANOTHER WEAK SFC BOUNDARY... MUCH LIKE THE ONE
YESTERDAY. WINDS WILL SLOWLY BACK TO THE EAST ACROSS NRN AND CENTRAL
OK THROUGH THE AFTN. TEMPS WILL CLIMB INTO THE 50S FOR HIGHS.
OVERNIGHT... AS THE H500 RIDGE BROADENS ACROSS THE WRN U.S... A WEAK
H500 SHORT WAVE TROUGH WILL CONTINUE TO APPROACH FROM THE WEST
ACROSS ERN NM AND WEST TX. THIS WILL OPEN UP SOME MODEST SFC
MOISTURE RETURN FROM THE GULF. PAIRED WITH SOME WEAK LL ISENTROPIC
ASCENT AS THE TROUGH SWINGS THROUGH... SOME LIGHT SHOWERS/DRIZZLE
MAY DEVELOP ACROSS THE RED RIVER VALLEY LATE WED INTO THU.
SLIGHT CHANCES FOR SHOWERS AND DRIZZLE ACROSS PORTIONS OF SOUTHERN
AND CENTRAL OK WILL CONTINUE THROUGH FRI AS THE RIDGE OVER THE
MIDWEST STRENGTHENS... LEAVING THE SRN PLAINS WITHIN THE WARM SECTOR
AND CONTINUAL SFC MOISTURE RETURN. OVERALL... MOST WILL REMAIN
DRY... WITH MILD TEMPERATURES CONTINUING.
FOR THE WEEKEND... LONG RANGE GUIDANCE... GFS/GFS13KM/ECMWF/CA...
HAVE CONTINUED TO SHOW DECENT CONTINUITY OVER THE PAST COUPLE RUNS
WITH RESPECT TO THE DEEP H500 TROUGH MOVING INTO THE PLAINS SAT.
INCREASED PRECIP CHCS SAT NIGHT INTO SUN. EXPECT SOME RUMBLES OF
THUNDER ON SUNDAY. A DECENT LOW... BUFR SOUNDINGS FROM KSPS TO KOUN
SHOW COLD TEMPS ALOFT... ENOUGH FOR SOME MINOR ELEVATED INSTABILITY
SUPPORTIVE OF SOME ISOLATED THUNDER WITHIN THE RAIN SHOWERS THAT
DEVELOP. NOT EXPECTING ANY SIGNIFICANT WEATHER... BUT THE POTENTIAL
FOR SOME WELCOME RAINFALL ACROSS THE REGION.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 55 36 55 45 / 0 0 10 10
HOBART OK 57 40 55 46 / 0 0 10 10
WICHITA FALLS TX 58 42 58 48 / 0 0 10 20
GAGE OK 54 37 54 42 / 0 0 10 10
PONCA CITY OK 48 32 50 42 / 0 0 10 20
DURANT OK 60 40 55 45 / 0 0 0 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR OKZ033>048-
050>052.
TX...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR TXZ083>090.
&&
$$
30/04/04
AREA FORECAST DISCUSSION
NWS NORMAN OK
258 AM CST TUE DEC 9 2014
.DISCUSSION...
IN RESPONSE TO VERY SHALLOW SFC MOISTURE ACROSS TEXOMA AND THE RED
RIVER VALLEY... DENSE FOG WILL REMAIN IN PLACE ACROSS SRN OK AND WRN
N TX. RECENT RAP AND HRRR OUTPUT OF VIS AND BOUNDARY LAYER RH VALUES
HINT AT FOG EXPANSION NORTHWARD INTO CENTRAL OK FOR AN HOUR OR TWO
NEAR SUNRISE BEFORE CONDITIONS IMPROVE THROUGH THE MID TO LATE
MORNING HOURS. IN RESPONSE TO THIS... HAVE MADE THE DECISION TO
EXTEND THE CURRENT DENSE FOG ADVISORY THROUGH 16Z (10AM CST). AT THE
MOMENT... NOT CONVINCED OF WIDESPREAD DENSE FOG REACHING FARTHER
NORTH THAN THE CURRENT ADVISORY. HOWEVER... SOME POCKETS OF SHORT
DURATION DENSE FOG WILL BE POSSIBLE OUTSIDE THE ADVISORY. WITH THAT
IN MIND... AND GIVEN THE CURRENT VIS TRENDS THROUGH 230AM CST...
THERE ARE NO PLANS TO EXPAND THE ADVISORY FARTHER NORTH AT THE
MOMENT. WE WILL CONTINUE TO WATCH VIS TRENDS CLOSELY THIS MORNING IN
THE EVENT AN EXPANSION IS NECESSARY.
FOR THE REST OF TODAY... HELPING CLEAR FOG SOUTHWARD THROUGH THE
MORNING WILL BE ANOTHER WEAK SFC BOUNDARY... MUCH LIKE THE ONE
YESTERDAY. WINDS WILL SLOWLY BACK TO THE EAST ACROSS NRN AND CENTRAL
OK THROUGH THE AFTN. TEMPS WILL CLIMB INTO THE 50S FOR HIGHS.
OVERNIGHT... AS THE H500 RIDGE BROADENS ACROSS THE WRN U.S... A WEAK
H500 SHORT WAVE TROUGH WILL CONTINUE TO APPROACH FROM THE WEST
ACROSS ERN NM AND WEST TX. THIS WILL OPEN UP SOME MODEST SFC
MOISTURE RETURN FROM THE GULF. PAIRED WITH SOME WEAK LL ISENTROPIC
ASCENT AS THE TROUGH SWINGS THROUGH... SOME LIGHT SHOWERS/DRIZZLE
MAY DEVELOP ACROSS THE RED RIVER VALLEY LATE WED INTO THU.
SLIGHT CHANCES FOR SHOWERS AND DRIZZLE ACROSS PORTIONS OF SOUTHERN
AND CENTRAL OK WILL CONTINUE THROUGH FRI AS THE RIDGE OVER THE
MIDWEST STRENGTHENS... LEAVING THE SRN PLAINS WITHIN THE WARM SECTOR
AND CONTINUAL SFC MOISTURE RETURN. OVERALL... MOST WILL REMAIN
DRY... WITH MILD TEMPERATURES CONTINUING.
FOR THE WEEKEND... LONG RANGE GUIDANCE... GFS/GFS13KM/ECMWF/CA...
HAVE CONTINUED TO SHOW DECENT CONTINUITY OVER THE PAST COUPLE RUNS
WITH RESPECT TO THE DEEP H500 TROUGH MOVING INTO THE PLAINS SAT.
INCREASED PRECIP CHCS SAT NIGHT INTO SUN. EXPECT SOME RUMBLES OF
THUNDER ON SUNDAY. A DECENT LOW... BUFR SOUNDINGS FROM KSPS TO KOUN
SHOW COLD TEMPS ALOFT... ENOUGH FOR SOME MINOR ELEVATED INSTABILITY
SUPPORTIVE OF SOME ISOLATED THUNDER WITHIN THE RAIN SHOWERS THAT
DEVELOP. NOT EXPECTING ANY SIGNIFICANT WEATHER... BUT THE POTENTIAL
FOR SOME WELCOME RAINFALL ACROSS THE REGION.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 55 36 55 45 / 0 0 10 10
HOBART OK 57 40 55 46 / 0 0 10 10
WICHITA FALLS TX 58 42 58 48 / 0 0 10 20
GAGE OK 54 37 54 42 / 0 0 10 10
PONCA CITY OK 48 32 50 42 / 0 0 10 20
DURANT OK 60 40 55 45 / 0 0 0 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR OKZ036-037-
044>048-050>052.
TX...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR TXZ083>090.
&&
$$
30/04
AS MENTIONED IN THE AFTERNOON FORECAST DISCUSSION... WILL LIKELY
SEE AT LEAST PATCHY FOG DEVELOP TONIGHT... ESPECIALLY ACROSS THE
SOUTHERN HALF OF OKLAHOMA AND NORTH TEXAS. NAM MOS GUIDANCE...
HRRR AND RAP SUGGEST THAT VISIBILITIES LESS THAN 1/2SM WILL BE
POSSIBLE AT KSPS.. KLAW... KHBR AND PERHAPS NORTH UP TO KOUN...
KOKC AND KCSM. AT THE MOMENT... HAVE JUST PUT A TEMPO GROUP TO 1SM
OR 2SM AT SOME OF THE CENTRAL AND SOUTHERN SITES BUT WILL WATCH
TRENDS FOR INDICATION OF HIGHER CHANCES OF THE DENSE FOG.
PREV DISCUSSION... /ISSUED 358 PM CST MON DEC 8 2014/
DISCUSSION...
ONLY A SMALL AREA OF STRATUS REMAIN THIS AFTERNOON NEAR AND SOUTH
OF THE RED RIVER. EXPECT AT LEAST SOME PATCHY FOG TO DEVELOP SOUTH
OF I40 TONIGHT UNDER THE INFLUENCE OF LIGHT WINDS AND MOSTLY CLEAR
SKIES. AFTER SUNRISE TOMORROW...A COLD FRONT WILL MOVE INTO OK
ALTHOUGH IT WILL FEEL WARMER THAN THE LAST FEW DAYS WITH CLEAR
SKIES PRESENT. BY WED...SOUTH WINDS WILL RETURN BUT CLOUD COVER
WILL BEGIN TO INCREASE FROM WEST TO EAST AS TWO MINOR SHORTWAVE
TROUGH IMPACT THE REGION AND MOISTURE INCREASES. DRIZZLE APPEARS
POSSIBLE ALONG A STATIONARY BOUNDARY NEAR THE KS/OK BORDER THURS
AM...WITH PATCHY FOG AND A SCHC OF RAIN FOR MOST OTHER LOCATIONS.
LOW LEVEL MOISTURE WILL INCREASE THURS WITH SOUTH WINDS
PRESENT...AND CONTINUE THROUGH THIS WEEKEND. THIS WAA REGIME WILL
LIKELY RESULT IN MORE STRATUS...FOG...AND DRIZZLE THROUGH SATURDAY.
IT WILL ALSO RESULT IN A DIFFICULT TEMP FORECAST. FOR NOW...WILL
KEEP LOWS A FEW DEGREES WARMER AND HIGHS A FEW DEGREES LOWER
ANTICIPATING WIDESPREAD CLOUD COVER THROUGH THIS WEEKEND.
HOWEVER...LOCATIONS OUT WEST COULD CLIMB UP INTO THE 70S SATURDAY
OUTSIDE THE INFLUENCE OF THE CLOUDS/LIGHT RAIN/DRIZZLE WHERE 850MB
TEMPS COULD REACH THE MID TEENS.
RAIN CHANCES WILL INCREASE SIGNIFICANTLY LATE SAT THROUGH SUN AS A
DEEP TROUGH APPROACHES THE SOUTHERN PLAINS. WILL INCLUDE A SMALL
AREA OF LIKELY POPS WEST OF THE OKC METRO FOR NOW SUN...BUT GIVEN
AGREEMENT AND CONSISTENCY BETWEEN MODELS THESE WILL LIKELY
INCREASE OVER THE NEXT SEVERAL DAYS ESPECIALLY OVER THE CENTRAL
AND EASTERN ZONES.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 38 57 37 56 / 0 0 0 10
HOBART OK 38 58 40 57 / 0 0 0 10
WICHITA FALLS TX 39 62 42 62 / 0 0 0 10
GAGE OK 34 58 39 57 / 0 0 0 10
PONCA CITY OK 34 50 31 50 / 0 0 0 20
DURANT OK 40 62 38 57 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...DENSE FOG ADVISORY UNTIL 8 AM CST TUESDAY FOR OKZ036-037-044>048-
050>052.
TX...DENSE FOG ADVISORY UNTIL 8 AM CST TUESDAY FOR TXZ083>090.
&&
$$
99/99/01
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
214 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE FORMING EAST OF THE CAROLINA COAST WILL MOVE UP THE
EAST COAST AND BRING AN EXTENDED PERIOD OF WINTRY WEATHER TO THE
REGION. BLUSTERY NORTHWEST FLOW WITH AREAS OF SNOW SHOWERS WILL
FOLLOW THIS STORM FOR THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
PRECIP LIFTING NORTH INTO THE SC MTNS LATE THIS EVENING IN REGION
OF LG SCALE FORCING AHEAD OF LEAD SHORTWAVE OVR THE S APPALACHIANS.
SATL-DERIVED PWAT LOOP SHOWING DEEP LVL MOISTURE LIFTING NORTHWARD
THRU THE MID ATLANTIC REGION ALONG AXIS OF EASTERLY LL JET. HAVE
ACCELERATED THE ARRIVAL OF PRECIP BASED ON RADAR TRENDS AND ALSO
HAVE TRENDED PTYPE TO MOSTLY SNOW ACROSS THE SPINE OF THE
ALLEGHENIES BASED ON UPSTREAM REPORTS AND LATEST HRRR OUTPUT...WHICH
SUGGESTS A STRIPE OF A COUPLE INCHES OF SNOW IS NOW POSSIBLE LATE
TONIGHT FROM SOMERSET/BEDFORD CO NEWRD INTO THE CENTRAL MTNS.
FURTHER EAST...STILL THINKING A PERIOD OF FZRA IS MOST LIKELY OVR
THE SUSQ VALLEY EARLY TUE AM.
BLEND OF 18Z CONSALL AND LATEST LAMP/HRRR OUTPUT SUGGEST TEMPS BY
DAWN WILL RANGE FROM THE U20S OVR THE ALLEGHENY MTNS...TO PERHAPS
JUST ABV FREEZING OVR LANCASTER CO.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/...
STILL A VERY UNCERTAIN FORECAST DESPITE HOW CLOSE WE ARE TO THE
ONSET OF THINGS.
A LOW DEVELOPING OFF THE CAROLINA COAST WILL MOVE DUE NORTH AND UP
ALONG THE NJ COAST TUESDAY INTO WEDNESDAY. GIVEN THIS SLIGHTLY
OFFSHORE TRACK...EASTERN PA WILL BEAR THE BRUNT OF THE STORM WITH
THE POTENTIAL FOR HEAVY RAIN OVR SE PA...AND POSSIBLY SOME SIG
SNOW OVER THE HIGHER ELEVATIONS OF TIOGA/SULLIVAN/SCHUYLKILL
COUNTIES.
WILL LIKELY BE ABLE TO CANCEL WINT WX ADVISORY BEFORE 18Z...AS
NEARLY ALL GUIDANCE INDICATES TEMPS RISING WELL ABV FREEZING BY
LATE AM. MAIN CONCERN WILL BE THE EARLY AM COMMUTE FOR A MIXTURE
OF SNOW AND FZRA.
MAIN FCST ISSUE REMAINS HOW FAR WEST SIG PRECIP CAN BE DRAGGED
INTO CENTRAL PA. MODELS ARE CONSISTENT IN A PRETTY SHARP BACK EDGE
CUTTING OFF MOST OF THE PRECIP SOMEWHERE BETWEEN STATE COLLEGE AND
PERHAPS WILLIAMSPORT-HARRISBURG.
WITH THE UNCERTAINTY STILL HIGH...WE KEPT THE WINTER STORM WATCH
UP FOR OUR HIGHER ELEVATIONS FROM TIOGA SOUTH DOWN INTO SCHUYLKILL
COUNTY...EMPHASIZING THE BEST CHANCE FOR HEAVY WET SNOW BEING OVER
THOSE HIGHER ELEVATIONS. LATEST RAP...21Z SREF AND 00Z NAM ALL
SUGGEST ENOUGH WARM AIR OVERSPREADS EASTERN PA TO TURN THE BULK
OF THE PRECIP TO RAIN BTWN LATE AM AND TUE AFTN OVR OUR NE
COUNTIES. HOWEVER...DEVELOPING DEFORMATION BAND ON THE NW
PERIPHERY OF MID LVL LOW COULD STILL POTENTIALLY PRODUCE SIG SNOW
TUE NIGHT FROM TIOGA CO SOUTH THRU SCHUYLKILL CO.
THE LOW IS EXPECTED TO REACH THE NJ COAST AROUND MID DAY TUESDAY
AND SLOW DOWN OR EVEN STALL FOR PERHAPS A DAY OR MORE AS THE UPPER
LOW CAPTURES THE SYSTEM. WHILE MUCH OF OUR FORECAST AREA WILL
LIKELY WARM ENOUGH TO MAKE FOR JUST PLAIN RAIN DURING THE DAY
TUESDAY...THIS WILL EVENTUALLY CAUSE COLDER AIR TO COME IN AT ALL
LEVELS AND CHANGE THE MIXED PRECIP BACK TO MAINLY SNOW TUESDAY
NIGHT AND INTO WED.
IT`S STILL UNCLEAR HOW MUCH PRECIP WILL RESULT AS THE MODELS
DIFFER GREATLY ON THE DEVELOPMENT OF A POSSIBLE DEFORMATION ZONE.
THE SOLUTIONS FALL BETWEEN THE ECMWF THAT TARGETS MY NWRN ZONES
EVEN THROUGH WED INTO THURSDAY...TO THE GFS THAT SHOWS ALMOST NO
PRECIP WRAPPING BACK. I KEPT A GOOD CHANCE OF MAINLY LIGHT QPF IN
THE FORECAST THROUGH THURSDAY BEFORE TAPERING OFF THE ACTIVITY
FOR THE REMAINDER OF THE WEEK.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WITH THE LOW MOVING VERY SLOWLY IF AT ALL...THE CHANCES FOR AT
LEAST SOME LIGHT SNOW WILL REMAIN HIGH WEDNESDAY INTO THURSDAY.
I GENERALLY KEPT AMOUNTS LOW...DEPENDENT ON THE FORMATION OF THE
DEFORMATION ZONE MENTIONED EARLIER...OR NOT.
BY THE END OF THE WEEK GUIDANCE IS IN DECENT AGREEMENT FOR THE
UPPER LOW TO NUDGE EAST ENOUGH TO HAVE US BEGINNING TO ENJOY THE
INFLUENCE OF SOME RIDGING AND FAIRER CONDITIONS.
TEMPS WILL BE COOLER THAN NORMAL THROUGH THE END OF THE WEEK
BEFORE BEGINNING TO MODERATE FOR THE WEEKEND.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
LOW PRESSURE OFF THE SOUTHEAST COAST WILL TRACK NORTH
NORTHWESTWARD EARLY THIS MORNING AND DEEPEN JUST OFF THE NEW
JERSEY COAST THIS AFTERNOON...THEN DRIFT NORTH TOWARD LONG ISLAND
TONIGHT INTO WEDNESDAY. INITIAL SHOT OF MIXED PCPN /SN-PL-FZRA/
CURRENTLY IMPACTING AIRFIELDS ALONG AND SE OF AOO-UNV-IPT LINE
SHOULD START TO TRANSITION TO/MIX WITH RAIN BTWN 12-15Z. BFD AND
JST WILL BE ON THE FAR WRN EDGE OF THE INITIAL PCPN SHIELD ASSOCD
WITH THE DEVELOPING COASTAL STORM AND MAY NOT SEE ANY PCPN UNTIL
TONIGHT. CONFIDENCE IS HIGH IN WIDESPREAD LOW MVFR TO IFR CIGS AND
MEDIUM FOR TIMING AND PTYPE TRANSITIONS THROUGH MID MORNING. WENT
WITH -RASN OR -RA AS SIG WX TYPES FROM THE LATE MORNING THROUGH
THE AFTERNOON WITH LOW CONFIDENCE ON THE SN. THERE IS A BETTER
CHANCE OF ANOTHER PTYPE TRANSITION/MIX FROM MOSTLY RA TO SNRA OR
JUST ALL SN TONIGHT ON THE BACKSIDE OF DEEPENING LOW AND MAY
ADDRESS THIS WITH THE 12Z ISSUANCE. WINDS WILL BECOME A FACTOR AT
ERN SITES TONIGHT SUSTAINED AT 15-20KT WITH HIGHER GUSTS.
THIS STORM WILL BE SLOW MOVING AND CONTINUE TO INFLUENCE THE
WEATHER PATTERN IN CENTRAL PA THROUGH AT LEAST THURSDAY WITH
ANOTHER ROUND OF WRAP AROUND SNOWS POSSIBLE. RETURN OF HIGH
PRESSURE SHOULD SPELL SOME MARGINAL IMPROVEMENT INTO THE WEEKEND.
OUTLOOK...
WED-THU...MVFR/IFR IN PERIODS OF SNOW. STRONG N-NW WINDS 15-20KTS
WITH HIGHER GUSTS POSSIBLE.
FRI...MVFR CIGS/-SHSN NW...BCMG VFR EAST.
SAT...VFR WITH HIGH PRESSURE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM 5 AM EST EARLY THIS MORNING THROUGH
WEDNESDAY MORNING FOR PAZ037-041-042-053-058.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ010>012-017>019-024>028-033>036-045-046-049>052-056-057-059-
063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...LA CORTE
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
941 PM CST WED DEC 10 2014
.UPDATE...
ISSUED AT 930 PM CST WED DEC 10 2014
MADE SOME ADJUSTMENTS TO THE FORECAST THIS EVENING. SATELLITE
SHOWS LOW STRATUS EXPANDING WEST ACROSS MOST OF THE CWA AND THUS
INCREASED CLOUD OVER. RAP AND HRRR SEEM TO HAVE A GOOD HANDLE AND
SUGGEST THESE LOW CLOUDS END UP COVERING THE ENTIRE CWA...EXCEPT
POSSIBLY GREGORY COUNTY...AND REMAIN INTO AT LEAST THURSDAY
MORNING. WILL HAVE TO WATCH FOR POSSIBLE DENSE FOG FORMATION ON
THE WESTERN EDGE OF THIS STRATUS SHIELD NEAR CHAMBERLAIN...AS SOME
GUIDANCE SUGGESTS THIS IS A POSSIBILITY. GIVEN THE CLOUD
COVER...WARMED LOWS ACROSS THE AREA...AS DO NOT THINK WE WILL SEE
MUCH OF A CHANGE FROM CURRENT READINGS.
OTHER CONCERN IS FREEZING DRIZZLE. STRATUS DEPTH IS PRETTY
SHALLOW...HOWEVER SEEING SOME LIGHT FREEZING DRIZZLE CURRENTLY
OUT THERE. ENOUGH WEAK LIFT IN THE CLOUD LAYER COMBINED WITH CLOUD
TOP COOLING AFTER SUNSET ARE PROBABLY TO BLAME. AS WE GET TOWARDS
MORNING THE MOISTURE BECOMES EVEN SHALLOWER...SO THINK FREEZING
DRIZZLE WILL DECREASE...BUT WILL HAVE TO MONITOR. AT THIS TIME...THINK
THE SHALLOW CLOUD DEPTH WILL PREVENT DRIZZLE FROM BECOMING HEAVY
ENOUGH TO CAUSE ANY MAJOR ISSUES...SO WILL JUST HIGHLIGHT IN AN
SPS...WITH SOME SURFACES POSSIBLY BECOMING A BIT ICY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 234 PM CST WED DEC 10 2014
THE MAIN CONCERNS TONIGHT INTO THURSDAY WILL BE STRATUS. HAVE LEANED
MORE PESSIMISTIC WITH THE THOUGHTS ON CLOUDS. MODELS SHOWING LIGHT
WESTERLY FLOW IN THE 850MB TO 700MB WHICH IS CREATING WEAK WARM AIR
ADVECTION. BELOW THIS THE INVERSION IS STRENGTHENING AS LIGHT
SOUTHERLY TO SOUTHEAST FLOW INCREASES MOISTURE WHICH SHOULD MAKE IT
DIFFICULT FOR MORE THAN A FEW BREAKS TO DEVELOP IN THE STRATUS. IF
WE CAN GET A FEW BREAKS IN THE CLOUD COVER FOG MIGHT BECOME AN ISSUE
BUT FOR NOW BELIEVE THAT MOST OF THE FOG WILL BE IN THE 3 TO 6 MILE
RANGE. SO WITH CLOUDS EXPECTED TO REMAIN IN PLACE THROUGH THE NIGHT
INTO THURSDAY WENT AHEAD AND INCREASED LOWS A BIT TONIGHT AND
DECREASED HIGHS A BIT ON THURSDAY...ESPECIALLY EAST OF THE JAMES
RIVER VALLEY. SO LOWS MAINLY MID TO UPPER 20S AND HIGHS ON THURSDAY
FROM THE MID 30S IN THE FAR EASTERN CWA TO THE LOWER 50S AROUND
GREGORY COUNTY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 234 PM CST WED DEC 10 2014
LOW LEVEL MOISTURE AND STRATUS SEEMS DESTINED TO BE CAMPED OVER
THE SOUTHEAST CORNER OF OUR AREA WILL INTO THE COMING WEEKEND. AT
THIS TIME WE STILL SEEM LIKELY TO KEEP MOSTLY CLEAR SKIES WITH THE
WARMING OVER OUR FAR WESTERN FORECAST AREA...BUT IT IS LIKELY TO BE
A FAIRLY SMALL PART. STRATUS WILL REDEVELOP NORTH/NORTHWEST AGAIN
LATE THURSDAY NIGHT...AT WHICH TIME GREATER AND MUCH DEEPER LOW
LEVEL MOISTURE WILL BEGIN TO ADVECT INTO THE AREA FROM THE SOUTH.
THIS SHOULD LEAD TO FAIRLY SOLID STRATUS HANGING IN OVER THE
SOUTHEAST HALF OF THE AREA FRIDAY AFTERNOON AND EXPANDING A BUT
FURTHER BY SATURDAY. ALONG WITH THIS...WILL KEEP DRIZZLE AND FOG
MENTION SOUTHEAST HALF FOR LATE FRIDAY NIGHT AND SATURDAY. OBVIOUSLY
THE BIG QUESTION IS JUST HOW FAR NORTHWEST THE SOLID CLOUD COVER
WILL GET...AND COULD NOT RULE OUT IT GETTING OVER EVEN THE FAR WEST
FOR A WHILE.
TEMPERATURES WILL CONTINUE TO WARM...ESPECIALLY WITH THAT SURGE
FRIDAY. SOME RECORD HIGH TEMPERATURES SEEM POSSIBLE SOUTHWEST
FRIDAY AND/OR SATURDAY WITH SOME LOWER 60S LIKELY...WITH RECORD HIGH
MINIMUMS EAST BY SATURDAY WHILE DAYTIME TEMPERATURES EAST CREEP
SLOWLY TO NEAR 50...STILL UNSEASONABLY WARM OF COURSE. INTERESTING
TO HAVE DRIZZLE MENTIONED DURING THE NIGHT AT THIS TIME OF YEAR AND
IT WOULD NOT BE FREEZING.
ON A TOSS UP...WILL GO WITH THE LOW POPS IN THE EXTENDED GUIDANCE
AND CARRY PRECIPITATION AS LIGHT RAIN SATURDAY NIGHT AND SUNDAY. WE
ALL KNOW OF COURSE THAT DRIZZLE CAN GET THICK ENOUGH WITH DROPLETS
APPROACHING THE BORDERLINE ZONE TO GET MEASURABLE. BY SUNDAY THERE
COULD BE SOME HIGHER BASED LIGHT RAIN WITH THE APPROACHING WAVE AND
COLD FRONT.
WITH COLDER AIR MONDAY...SYSTEM SHOWN BY MODELS COULD BRING WET
SNOW. GFS SHOWS THE DECENT PRECIPITATION MONDAY AND MONDAY NIGHT
JUST SOUTH OF THE AREA WHILE THE EC IS CLOSE TO INTERSTATE
90...THOUGH IT HAS GONE A BIT SOUTH FROM ITS PREVIOUS RUN. WILL
KEEP POPS MOSTLY AT THE CHANCE LEVEL WITH SOME LIKELIES FAR SOUTH
AND NOT GO WITH A WHOPPER AT THIS TIME.
TUESDAY AND WEDNESDAY SHOULD BE DRY AND SEASONABLY COLD...UNLESS THE
MONDAY SYSTEM SLOWS DOWN A LOT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 541 PM CST WED DEC 10 2014
ASIDE FROM A CLEAR PATCH IN EASTERN NEBRASKA...WHICH APPEARS TO BE
SLOWLY FILLING IN WITH CLOUDS...THE ENTIRE EASTERN PLAINS IS MIRED
IN IFR TO MVFR STRATUS. AS LONG AS THE WINDS STAY OUT OF THE SOUTH
AND SOUTHEAST WHICH THEY WILL...THE STRATUS MAY BE REALLY TOUGH TO
SCOUR OUT OF HERE. THEREFORE KEPT KHON...KFSD AND KSUX ON THE
PESSIMISTIC SIDE OF IFR TO LOW END MVFR CONDITIONS THROUGH
THURSDAY. ANOTHER THING TO CONSIDER IS IF ANY LOCATION DID TRY TO
CLEAR OUT LATE TONIGHT...THEN LIFR AND VLIFR UNDER FOG WOULD BE A
MAJOR CONCERN.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...08
LONG TERM...
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1051 PM CST MON DEC 8 2014
.UPDATE...
ISSUED AT 904 PM CST MON DEC 8 2014
SHORT TERM CLOUD TRENDS HAVE BEEN CHALLENGING TO SAY THE LEAST.
STRONG PUSH OF CLEARING HAS OCCURRED FROM THE JAMES VALLEY
THROUGH I 29 CORRIDOR IN THE VICINITY OF THE LOW LEVEL RIDGE
AXIS... NARROWING AND BACKING BAND OF LOWER CLOUDS ACROSS THE FAR
WESTERN CWA...WHILE BREAKS HAVE DEVELOPED IN CLOUDS ACROSS THE
EAST...BUT FAR LESS IMPRESSIVELY. IN CLEARING...TEMPS HAVE FALLEN
MUCH FASTER AS HAVE THE WINDS...WHILE STILL GUSTY AND RELATIVELY
WARMER UNDER CLOUDS TO EAST. CLEARING WEDGE WILL CONTINUE TO WORK
SOUTHWARD LATE THIS EVENING WHILE A SLOWER BACKING TO NARROW BAND
OF LOW CLOUDS WORKS OUT OF SOUTH CENTRAL. WILL SEE CLOUDS AGAIN
INCREASE FROM THE NORTH ALONG/EAST OF THE I29 CORRIDOR AS FINAL
LOBE WRAPS SOUTHEAST ACROSS THE AREA...WITH GENERAL NORTH TO
NORTHEAST FLOW IN CLOUD BEARING LEVELS. DOWNSLOPE OFF THE RIDGE
WITH NARROWING MOISTURE DEPTH COULD CREATE A FEW ISSUES WORKING
CLOUDS MUCH SOUTHWEST PAST KFSD...AND EVEN TO KFSD. COULD POSSIBLY
SEE A FEW FLURRIES START TO FLUTTER THROUGH SKIES IN THE NORTHEAST
AFTER 08Z...BUT AT THIS POINT NOT MUCH MERIT IN THE MENTION WITH
TEMPS IN THE CLOUD LAYER SOMEWHAT MARGINAL.
HAVE TRIMMED A COUPLE OF LOWS DOWN A BIT IN VICINITY OF RIDGE AXIS
AND CLEARING...BUT IN GENERAL EVEN ADVECTION WILL TAKE LOWS TO
EARLIER LEVELS...JUST A BIT QUICKER OF A START THIS EVENING TO
THOSE ENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 244 PM CST MON DEC 8 2014
THE MAIN QUESTION THROUGH THIS EVENING IS THE STATUS OF THE LOW
CLOUD COVER WHICH HAD BEEN SPREADING SOUTH OVER THE AREA. THAT
SPREAD HAS DONE A NEAR HALT AS THE MOISTURE ADVECTION RUNS INTO THE
HEATED AIR NEAR THE MISSOURI RIVER. IT SEEMS WITH THE START OF
EARLY EVENING COOLING THAT THE DECK WOULD AGAIN START SPREADING
SOUTH. CLEARING OF THE LOW CLOUDS HAS CONTINUED TO PROGRESS SOUTH
ACROSS NORTH DAKOTA AND WAS STARTING TO GET INTO FAR NORTHERN SOUTH
DAKOTA AT 20Z. BOTH THE NAM AND RAP SUGGEST THE 925 MB FLOW WILL
CONTINUE TO GO STRAIGHT NORTHERLY AND CONTINUE THUS OVER THE AREA
THROUGH 06Z/MIDNIGHT...THOUGH DECREASING SLOWLY DURING THE
EVENING. EXPECT THIS WILL GIVE THE DRYING CONTINUED TRANSPORT
SOUTH ACROSS THE AREA DURING THE EVENING AND NOT ALLOW THE SOLID
CLOUD COVER TO GET ALL THE WAY TO THE RIVER...OR OF IT BRIEFLY
DOES...IT SHOULD CLEAR OUT AGAIN FAIRLY QUICKLY. AM PLANNING FOR A
LITTLE INCREASE IN THE LOW CLOUDS THERE BUT WITH THE WARM AIR
THERE CURRENTLY AND DRYING FROM THE NORTH DURING THE
EVENING...HAVE KEPT THE INCREASE VERY MODEST BEFORE IT CLEARS OUT
EVERYWHERE TONIGHT.
TEMPERATURES WILL COOL STEADILY TONIGHT GIVEN THE CLEARING AND
DROPOFF IN WINDS...WITH LOWS BEING REACH ABOUT SUNRISE AT 8 AM.
WINDS BY THEN SHOULD BE PRETTY LIGHT THOUGH WITH A 5 TO 5 MPH
NORTHERLY BREEZE IN THE EAST LINGERING TO SUNUP.
TUESDAY WILL BRING AN INCREASE IN HIGH AND SOME MIDDLE CLOUDS WITH
UPPER LEVEL SHORT WAVE DRIFTING INTO THE AREA. HAVE GONE PRETTY
CONSERVATIVE IN CLOUD COVER AND IF THEY HIGHER CLOUDS ARE THICK
ENOUGH IT COULD GET MOSTLY CLOUDY FOR PART OF THE DAY. IN ANY EVENT
HEATING BY THE DECEMBER SUN WILL NOT BE ABLE TO TAKE ADVANTAGE OF
MUCH OF THE WARMING UPSTAIRS EVEN WITH NO SNOW COVER...AND FORECAST
HIGHS WILL REMAIN AROUND 30 NORTHEAST TO THE LOWER 40S SOUTHWEST.
WINDS WILL BE FAIRLY LIGHT THOUGH...WITH THE DEVELOPING
SOUTHEASTERLY SURFACE BREEZE PICKING TO 10 PLUS IN THE AFTERNOON
WEST OF THE JAMES RIVER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 244 PM CST MON DEC 8 2014
MEDIUM AND EXTENDED FORECAST CONTINUES TO LOOK VERY WARM AND MOSTLY
DRY. TUESDAY NIGHT INTO WEDNESDAY...A MINOR SHORTWAVE WILL MOVE
ACROSS THE REGION. SOUNDINGS CONTINUE TO SHOW LIMITED MOISTURE WITH
THIS WAVE...WITH AN INCREASE IN MID-LVL CLOUDS AND VIRGA POSSIBLE
GIVEN DRY SUB-CLOUD LAYER.
THE WARMUP BEGINS TO BUILD ON WEDNESDAY BEHIND THIS SHORTWAVE
ENERGY. AS LOW LVL TEMPERATURES BUILD...SURFACE WINDS WILL SLOWLY
BEGIN TO VEER SOUTHWEST THROUGH THE DAY. WARM AIR WILL BE SLOW TO
MIX TO THE SURFACE ON WEDNESDAY...BUT NEAR 40 READINGS SHOULD BE
ATTAINABLE.
THURSDAY THROUGH SATURDAY LOOK TO BE VERY WARM AS DEEP
SOUTHWESTERLY FLOW PULLS BOTH MOISTURE AND WARM AIR OVER MUCH OF
THE CENTRAL CONUS. IT CONTINUES TO LOOK LIKE STRATUS WILL DEVELOP
AND MOVE NORTHWARD INTO THE REGION BY THURSDAY. TEMPERATURES WILL
PROGRESSIVELY WARM EACH AFTERNOON...WITH THE 40S LIKELY ON
THURSDAY AND 40S AND 50S ON FRIDAY. TEMPERATURES MAY NOT FALL VERY
FALL FRIDAY NIGHT INTO SATURDAY...AND CURRENT LOWS MAY STILL BE
TOO LOW. THE DEEP SOUTHERLY FLOW AND SUBSTANTIAL MOISTURE SHOULD
NOT ALLOW FOR ANY EXTREME JUMP ON SATURDAY...BUT A GRADUAL WARMING
INTO THE MID 50S AND POTENTIALLY EVEN DRIZZLE.
A COLD FRONT WILL SWING THROUGH THE AREA SATURDAY NIGHT INTO
SUNDAY...DROPPING TEMPERATURES BACK NEAR THEIR SEASONAL NORMALS. THE
CHANCES FOR PRECIPITATION AS THIS FRONT MOVES THROUGH CONTINUE TO
BE LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1051 PM CST MON DEC 8 2014
MVFR CEILINGS EXPECTED TO SLOWLY SHIFT SOUTH-SOUTHWESTWARD THROUGH
CENTRAL/EASTERN PORTIONS OF THE FORECAST AREA THROUGH THE MORNING.
MVFR CEILINGS MOST LIKELY TO AFFECT KFSD TAF LOCATION FOR PROLONGED
PERIOD THROUGH MID MORNING. LOWER CONFIDENCE FOR KHON/KSUX DUE TO
UNCERTAINTY REGARDING WESTWARD EXTENT OF THE LOWER CLOUD DECK.
MODELS PROJECT THE STRATUS LAYER TO GRADUALLY THIN WEST TO EAST
AFTER SUNRISE AS LOW LEVEL RIDGE AXIS WORKS THROUGH THE AREA. THUS
IMPROVEMENT TO VFR GRADUALLY EXPECTED ALONG I-29 CORRIDOR BY 16-18Z
WITH VFR CONDITIONS THEN PREVAILING THROUGH THE END OF THE PERIOD.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHAPMAN
SHORT TERM...
LONG TERM...DUX
AVIATION...JH
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
940 PM EST WED DEC 10 2014
.DISCUSSION...
CLOUDS HAVE BEGUN TO DISSIPATE ACROSS SW PARTS OF THE AREA...BUT
ARE REMAINING OVERCAST NORTH AND EAST. EXPECT THAT THE NORTHERN
HALF WILL REMAIN OVERCAST THROUGH THE NIGHT WERE MODELS SHOW 850 MB
COLD ADVECTION PERSISTING...AND WHERE THE MOUNTAINS CAN HELP TRAP
MOISTURE BELOW THE INVERSION. THE LATEST RAP SOUNDINGS APPEAR TO
ERODE THE CLOUDS TOO QUICKLY...AND PREFER THE NAM WHICH HOLDS
MOISTURE IN PLACE THROUGH THE MORNING. WILL MAKE SOME ADJUSTMENTS
TO SKY AND TEMPERATURE GRIDS...AND REMOVE THE SLIGHT CHANCE OF SNOW
SHOWERS NORTH AS RADAR LOOKS CLEAR.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1217 PM CST TUE DEC 9 2014
.UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE MENTIONING OF
MORNING WORDING IN THE ZONE FORECAST PRODUCT...TWEAK HRLY TEMPS...
DEWPOINT...WIND...AND SKY CONDITION GRID TRENDS...AND TRIM BACKED
TO MAINLY AREAS ACROSS PLATEAU REGION WHERE WINTRY MIX MIGHT OCCUR
THRU AFTERNOON HRS.
&&
.PREV DISCUSSION... /ISSUED 1154 AM CST TUE DEC 9 2014/
UPDATE...FOR 18Z AVIATION DISCUSSION.
AVIATION...18Z AVIATION DISCUSSION.
WITH LINGERING UPPER LEVEL TROUGH INFLUENCES AND THEN DEVELOPING NWLY FLOW
ALOFT...GENERALLY MVFR CEILINGS EXPECTED CKV/BNA THRU 10/18Z WITH NLY SFC
WINDS 5 TO 10 KTS...GUSTS TO 20KTS...POSSIBLE. MVFR CEILINGS SHOULD PERSIST
CSV THRU AT LEAST 10/03Z ALSO...WITH SOME LOWERING TO LOW END MVFR/HIGH END
IFR CEILINGS THRU 10/16Z. WEAK UPPER LEVEL DISTURBANCE WITHIN UPPER LEVEL
TROUGHING ACROSS PLATEAU REGION WILL CONTINUE TO RESULT IN POTENTIAL FOR
LIGHT WINTRY MIX THRU 10/03Z TRANSITIONING TO LIGHT SNOWFALL THRU AT LEAST
10/09Z...BUT ANY VSBY/IMPACTS TO AVIATION OPERATIONS MINIMAL AT BEST.
PREV DISCUSSION.../ISSUED 926 AM CST TUE DEC 9 2014/
UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS PER CURRENT HRLY TEMP...
DEWPOINT...WINDS...ALONG WITH HAVING TEMPS FALLING DURING THE
AFTERNOON HRS ACROSS PLATEAU REGION. OTHERWISE...CURRENT FORECAST
AND BELOW FORECAST REASONING REMAIN ON TRACK.
WE ARE STILL EXPERIENCING COMMS PROBLEMS HERE AT THE NWS NASHVILLE
OFFICE WHICH INCLUDES PHONE LINES WORKING OFF AN ON...INTERNET DOWN...
ALONG WITH NWR OUTAGES. TECHNICIANS ARE CONTINUE TO LOOK INTO
THIS PROBLEM AND APPOLOGIZE FOR ANY INCONVIENCES THAT IT HAS OR MIGHT
CAUSE THIS MORNING AND HOPE TO HAVE THIS FIXED AS SOON AS POSSIBLE.
PREV DISCUSSION.../ISSUED 649 AM CST TUE DEC 9 2014/
UPDATE...FOR 12Z TAFS.
AVIATION...
PLENTY OF LOW-LEVEL MOISTURE REMAINING ACROSS THE MID-STATE
BEHIND PASSING UPPER TROUGH. THIS WILL LEAVE PLENTY OF CLOUDS
ACROSS THE REGION...LARGELY AT VFR HEIGHTS BUT CLOUDS ARE
EXPECTED TO LOWER/REFORM OVERNIGHT AND THOSE MAY BE AOB 3KFT.
SOME LIGHT MIXED PCPN ALSO POSSIBLE CSV TODAY. WINDS ARE EXPECTED
TO BECOME QUITE GUSTY FOR THE NORTHWEST BY MIDDAY.
PREV DISCUSSION.../ISSUED 330 AM CST TUE DEC 9 2014/
DISCUSSION...
UPPER LEVEL SYSTEM OVER INDIANA WILL DROP SOUTHEASTWARD THIS
MORNING AND WILL MOVE ACROSS EASTERN TN THIS AFTERNOON. THOUGH THE
BETTER DEFORMATIONAL INFLUENCES WILL BE TO THE LEFT OF THE
TRACK...WE DO PICK UP SOME DESCENT CURVATURE AND SHEAR ON THE
RIGHT SIDE OF THE TRACK. LATEST SATELLITE IMAGERY SHOWS THE LOWER
TO MID LEVEL CLOUDINESS TO OUR NORTH ACROSS IL...IN AND NRN MO.
LATEST HRRR AND MODEL DATA BOTH CONCUR WITH SCATTERED LIGHT SHOWER
ACTIVITY ACROSS THE EASTERN PORTIONS OF THE MID STATE THROUGH
TODAY AND INTO TONIGHT. AN EXAMINATION OF FREEZING LEVELS DOES
SUPPORT SNOW FOR AREAS GENERALLY ABOVE 1500 FT MSL AFT 18Z TODAY.
BY 00Z THE ENTIRE EASTERN THIRD OF THE MID STATE...WHERE THE
CHANCES OF PRECIP EXISTS...WILL BE SNOW. AMOUNTS LOOK VERY LIGHT
AND NO ADVISORIES OR SPS PRODUCTS ARE NEEDED. FURTHERMORE...SFC
TEMPS SHOULD GENERALLY REMAIN ABOVE FREEZING UNTIL LATE TONIGHT.
A LOW CHANCE OF SNOWFALL WILL CONTINUE ACROSS THE EAST FOR TONIGHT
BUT AMOUNTS AGAIN WILL BE LIGHT.
FOR THE FCST...WILL INCLUDE A CHANCE OF RAIN AND SNOW EASTERN THIRD
FOR THIS MORNING...JUST RAIN SOUTHEAST. THIS AFTERNOON...WILL TREND
THE GRIDS TOWARD A CHANCE OF ALL SNOW FOR THE EASTERN AREA BY
EVENING. 850 MB TEMPS WILL BE WELL BELOW 0C AND FREEZING LEVELS
WILL BE DROPPING AS WELL AS SFC TEMPS WHICH WILL BE FALLING
THROUGH THE 30S.
IMPROVING CONDITIONS WILL OCCUR ON WEDNESDAY WITH PARTLY CLOUDY
SKIES EXPECTED. IN FACT...MOSTLY CLEAR AND MOSTLY SUNNY SKIES ARE ON
TAP FOR WED NT AND THU.
TEMPS THROUGH THE EXTENDED WILL REMAIN BELOW NORMAL AS A UNIFORM
NORTHERLY FLOW CONTINUES WITH ONLY A VERY SLOW INCREASE IN HEIGHT
VALUES.
IN THE EXTENDED FCST...HEIGHT VALUES WILL CONTINUE TO INCREASE WITH
A RIDGE AXIS REACHING THE AREA ON SATURDAY. THIS WILL EQUATE TO DRY
CONDITIONS AND A WARMING TREND. LATE IN THE EXTENDED HOWEVER...A
COLD FRONT WILL BRING AN INCREASE IN CLOUDINESS AND A LOW CHANCE OF
SHOWER ACTIVITY ON MONDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1154 AM CST TUE DEC 9 2014
.UPDATE...FOR 18Z AVIATION DISCUSSION.
&&
.AVIATION...18Z AVIATION DISCUSSION.
WITH LINGERING UPPER LEVEL TROUGH INFLUENCES AND THEN DEVELOPING NWLY FLOW
ALOFT...GENERALLY MVFR CEILINGS EXPECTED CKV/BNA THRU 10/18Z WITH NLY SFC
WINDS 5 TO 10 KTS...GUSTS TO 20KTS...POSSIBLE. MVFR CEILINGS SHOULD PERSIST
CSV THRU AT LEAST 10/03Z ALSO...WITH SOME LOWERING TO LOW END MVFR/HIGH END
IFR CEILINGS THRU 10/16Z. WEAK UPPER LEVEL DISTURBANCE WITHIN UPPER LEVEL
TROUGHING ACROSS PLATEAU REGION WILL CONTINUE TO RESULT IN POTENTIAL FOR
LIGHT WINTRY MIX THRU 10/03Z TRANSITIONING TO LIGHT SNOWFALL THRU AT LEAST
10/09Z...BUT ANY VSBY/IMPACTS TO AVIATION OPERATIONS MINIMAL AT BEST.
&&
.PREV DISCUSSION.../ISSUED 926 AM CST TUE DEC 9 2014/
UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS PER CURRENT HRLY TEMP...
DEWPOINT...WINDS...ALONG WITH HAVING TEMPS FALLING DURING THE
AFTERNOON HRS ACROSS PLATEAU REGION. OTHERWISE...CURRENT FORECAST
AND BELOW FORECAST REASONING REMAIN ON TRACK.
WE ARE STILL EXPERIENCING COMMS PROBLEMS HERE AT THE NWS NASHVILLE
OFFICE WHICH INCLUDES PHONE LINES WORKING OFF AN ON...INTERNET DOWN...
ALONG WITH NWR OUTAGES. TECHNICIANS ARE CONTINUE TO LOOK INTO
THIS PROBLEM AND APPOLOGIZE FOR ANY INCONVIENCES THAT IT HAS OR MIGHT
CAUSE THIS MORNING AND HOPE TO HAVE THIS FIXED AS SOON AS POSSIBLE.
PREV DISCUSSION.../ISSUED 649 AM CST TUE DEC 9 2014/
UPDATE...FOR 12Z TAFS.
AVIATION...
PLENTY OF LOW-LEVEL MOISTURE REMAINING ACROSS THE MID-STATE
BEHIND PASSING UPPER TROUGH. THIS WILL LEAVE PLENTY OF CLOUDS
ACROSS THE REGION...LARGELY AT VFR HEIGHTS BUT CLOUDS ARE
EXPECTED TO LOWER/REFORM OVERNIGHT AND THOSE MAY BE AOB 3KFT.
SOME LIGHT MIXED PCPN ALSO POSSIBLE CSV TODAY. WINDS ARE EXPECTED
TO BECOME QUITE GUSTY FOR THE NORTHWEST BY MIDDAY.
PREV DISCUSSION.../ISSUED 330 AM CST TUE DEC 9 2014/
DISCUSSION...
UPPER LEVEL SYSTEM OVER INDIANA WILL DROP SOUTHEASTWARD THIS
MORNING AND WILL MOVE ACROSS EASTERN TN THIS AFTERNOON. THOUGH THE
BETTER DEFORMATIONAL INFLUENCES WILL BE TO THE LEFT OF THE
TRACK...WE DO PICK UP SOME DESCENT CURVATURE AND SHEAR ON THE
RIGHT SIDE OF THE TRACK. LATEST SATELLITE IMAGERY SHOWS THE LOWER
TO MID LEVEL CLOUDINESS TO OUR NORTH ACROSS IL...IN AND NRN MO.
LATEST HRRR AND MODEL DATA BOTH CONCUR WITH SCATTERED LIGHT SHOWER
ACTIVITY ACROSS THE EASTERN PORTIONS OF THE MID STATE THROUGH
TODAY AND INTO TONIGHT. AN EXAMINATION OF FREEZING LEVELS DOES
SUPPORT SNOW FOR AREAS GENERALLY ABOVE 1500 FT MSL AFT 18Z TODAY.
BY 00Z THE ENTIRE EASTERN THIRD OF THE MID STATE...WHERE THE
CHANCES OF PRECIP EXISTS...WILL BE SNOW. AMOUNTS LOOK VERY LIGHT
AND NO ADVISORIES OR SPS PRODUCTS ARE NEEDED. FURTHERMORE...SFC
TEMPS SHOULD GENERALLY REMAIN ABOVE FREEZING UNTIL LATE TONIGHT.
A LOW CHANCE OF SNOWFALL WILL CONTINUE ACROSS THE EAST FOR TONIGHT
BUT AMOUNTS AGAIN WILL BE LIGHT.
FOR THE FCST...WILL INCLUDE A CHANCE OF RAIN AND SNOW EASTERN THIRD
FOR THIS MORNING...JUST RAIN SOUTHEAST. THIS AFTERNOON...WILL TREND
THE GRIDS TOWARD A CHANCE OF ALL SNOW FOR THE EASTERN AREA BY
EVENING. 850 MB TEMPS WILL BE WELL BELOW 0C AND FREEZING LEVELS
WILL BE DROPPING AS WELL AS SFC TEMPS WHICH WILL BE FALLING
THROUGH THE 30S.
IMPROVING CONDITIONS WILL OCCUR ON WEDNESDAY WITH PARTLY CLOUDY
SKIES EXPECTED. IN FACT...MOSTLY CLEAR AND MOSTLY SUNNY SKIES ARE ON
TAP FOR WED NT AND THU.
TEMPS THROUGH THE EXTENDED WILL REMAIN BELOW NORMAL AS A UNIFORM
NORTHERLY FLOW CONTINUES WITH ONLY A VERY SLOW INCREASE IN HEIGHT
VALUES.
IN THE EXTENDED FCST...HEIGHT VALUES WILL CONTINUE TO INCREASE WITH
A RIDGE AXIS REACHING THE AREA ON SATURDAY. THIS WILL EQUATE TO DRY
CONDITIONS AND A WARMING TREND. LATE IN THE EXTENDED HOWEVER...A
COLD FRONT WILL BRING AN INCREASE IN CLOUDINESS AND A LOW CHANCE OF
SHOWER ACTIVITY ON MONDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
926 AM CST TUE DEC 9 2014
.UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS PER CURRENT HRLY TEMP...
DEWPOINT...WINDS...ALONG WITH HAVING TEMPS FALLING DURING THE
AFTERNOON HRS ACROSS PLATEAU REGION. OTHERWISE...CURRENT FORECAST
AND BELOW FORECAST REASONING REMAIN ON TRACK.
WE ARE STILL EXPERIENCING COMMS PROBLEMS HERE AT THE NWS NASHVILLE
OFFICE WHICH INCLUDES PHONE LINES WORKING OFF AN ON...INTERNET DOWN...
ALONG WITH NWR OUTAGES. TECHNICIANS ARE CONTINUE TO LOOK INTO
THIS PROBLEM AND APPOLOGIZE FOR ANY INCONVIENCES THAT IT HAS OR MIGHT
CAUSE THIS MORNING AND HOPE TO HAVE THIS FIXED AS SOON AS POSSIBLE.
&&
.PREV DISCUSSION.../ISSUED 649 AM CST TUE DEC 9 2014/
UPDATE...FOR 12Z TAFS.
AVIATION...
PLENTY OF LOW-LEVEL MOISTURE REMAINING ACROSS THE MID-STATE
BEHIND PASSING UPPER TROUGH. THIS WILL LEAVE PLENTY OF CLOUDS
ACROSS THE REGION...LARGELY AT VFR HEIGHTS BUT CLOUDS ARE
EXPECTED TO LOWER/REFORM OVERNIGHT AND THOSE MAY BE AOB 3KFT.
SOME LIGHT MIXED PCPN ALSO POSSIBLE CSV TODAY. WINDS ARE EXPECTED
TO BECOME QUITE GUSTY FOR THE NORTHWEST BY MIDDAY.
PREV DISCUSSION.../ISSUED 330 AM CST TUE DEC 9 2014/
DISCUSSION...
UPPER LEVEL SYSTEM OVER INDIANA WILL DROP SOUTHEASTWARD THIS
MORNING AND WILL MOVE ACROSS EASTERN TN THIS AFTERNOON. THOUGH THE
BETTER DEFORMATIONAL INFLUENCES WILL BE TO THE LEFT OF THE
TRACK...WE DO PICK UP SOME DESCENT CURVATURE AND SHEAR ON THE
RIGHT SIDE OF THE TRACK. LATEST SATELLITE IMAGERY SHOWS THE LOWER
TO MID LEVEL CLOUDINESS TO OUR NORTH ACROSS IL...IN AND NRN MO.
LATEST HRRR AND MODEL DATA BOTH CONCUR WITH SCATTERED LIGHT SHOWER
ACTIVITY ACROSS THE EASTERN PORTIONS OF THE MID STATE THROUGH
TODAY AND INTO TONIGHT. AN EXAMINATION OF FREEZING LEVELS DOES
SUPPORT SNOW FOR AREAS GENERALLY ABOVE 1500 FT MSL AFT 18Z TODAY.
BY 00Z THE ENTIRE EASTERN THIRD OF THE MID STATE...WHERE THE
CHANCES OF PRECIP EXISTS...WILL BE SNOW. AMOUNTS LOOK VERY LIGHT
AND NO ADVISORIES OR SPS PRODUCTS ARE NEEDED. FURTHERMORE...SFC
TEMPS SHOULD GENERALLY REMAIN ABOVE FREEZING UNTIL LATE TONIGHT.
A LOW CHANCE OF SNOWFALL WILL CONTINUE ACROSS THE EAST FOR TONIGHT
BUT AMOUNTS AGAIN WILL BE LIGHT.
FOR THE FCST...WILL INCLUDE A CHANCE OF RAIN AND SNOW EASTERN THIRD
FOR THIS MORNING...JUST RAIN SOUTHEAST. THIS AFTERNOON...WILL TREND
THE GRIDS TOWARD A CHANCE OF ALL SNOW FOR THE EASTERN AREA BY
EVENING. 850 MB TEMPS WILL BE WELL BELOW 0C AND FREEZING LEVELS
WILL BE DROPPING AS WELL AS SFC TEMPS WHICH WILL BE FALLING
THROUGH THE 30S.
IMPROVING CONDITIONS WILL OCCUR ON WEDNESDAY WITH PARTLY CLOUDY
SKIES EXPECTED. IN FACT...MOSTLY CLEAR AND MOSTLY SUNNY SKIES ARE ON
TAP FOR WED NT AND THU.
TEMPS THROUGH THE EXTENDED WILL REMAIN BELOW NORMAL AS A UNIFORM
NORTHERLY FLOW CONTINUES WITH ONLY A VERY SLOW INCREASE IN HEIGHT
VALUES.
IN THE EXTENDED FCST...HEIGHT VALUES WILL CONTINUE TO INCREASE WITH
A RIDGE AXIS REACHING THE AREA ON SATURDAY. THIS WILL EQUATE TO DRY
CONDITIONS AND A WARMING TREND. LATE IN THE EXTENDED HOWEVER...A
COLD FRONT WILL BRING AN INCREASE IN CLOUDINESS AND A LOW CHANCE OF
SHOWER ACTIVITY ON MONDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
649 AM CST TUE DEC 9 2014
.UPDATE...FOR 12Z TAFS.
&&
.AVIATION...
PLENTY OF LOW-LEVEL MOISTURE REMAINING ACROSS THE MID-STATE
BEHIND PASSING UPPER TROUGH. THIS WILL LEAVE PLENTY OF CLOUDS
ACROSS THE REGION...LARGELY AT VFR HEIGHTS BUT CLOUDS ARE
EXPECTED TO LOWER/REFORM OVERNIGHT AND THOSE MAY BE AOB 3KFT.
SOME LIGHT MIXED PCPN ALSO POSSIBLE CSV TODAY. WINDS ARE EXPECTED
TO BECOME QUITE GUSTY FOR THE NORTHWEST BY MIDDAY.
&&
.PREV DISCUSSION... /ISSUED 330 AM CST TUE DEC 9 2014/
DISCUSSION...
UPPER LEVEL SYSTEM OVER INDIANA WILL DROP SOUTHEASTWARD THIS
MORNING AND WILL MOVE ACROSS EASTERN TN THIS AFTERNOON. THOUGH THE
BETTER DEFORMATIONAL INFLUENCES WILL BE TO THE LEFT OF THE
TRACK...WE DO PICK UP SOME DESCENT CURVATURE AND SHEAR ON THE
RIGHT SIDE OF THE TRACK. LATEST SATELLITE IMAGERY SHOWS THE LOWER
TO MID LEVEL CLOUDINESS TO OUR NORTH ACROSS IL...IN AND NRN MO.
LATEST HRRR AND MODEL DATA BOTH CONCUR WITH SCATTERED LIGHT SHOWER
ACTIVITY ACROSS THE EASTERN PORTIONS OF THE MID STATE THROUGH
TODAY AND INTO TONIGHT. AN EXAMINATION OF FREEZING LEVELS DOES
SUPPORT SNOW FOR AREAS GENERALLY ABOVE 1500 FT MSL AFT 18Z TODAY.
BY 00Z THE ENTIRE EASTERN THIRD OF THE MID STATE...WHERE THE
CHANCES OF PRECIP EXISTS...WILL BE SNOW. AMOUNTS LOOK VERY LIGHT
AND NO ADVISORIES OR SPS PRODUCTS ARE NEEDED. FURTHERMORE...SFC
TEMPS SHOULD GENERALLY REMAIN ABOVE FREEZING UNTIL LATE TONIGHT.
A LOW CHANCE OF SNOWFALL WILL CONTINUE ACROSS THE EAST FOR TONIGHT
BUT AMOUNTS AGAIN WILL BE LIGHT.
FOR THE FCST...WILL INCLUDE A CHANCE OF RAIN AND SNOW EASTERN THIRD
FOR THIS MORNING...JUST RAIN SOUTHEAST. THIS AFTERNOON...WILL TREND
THE GRIDS TOWARD A CHANCE OF ALL SNOW FOR THE EASTERN AREA BY
EVENING. 850 MB TEMPS WILL BE WELL BELOW 0C AND FREEZING LEVELS
WILL BE DROPPING AS WELL AS SFC TEMPS WHICH WILL BE FALLING
THROUGH THE 30S.
IMPROVING CONDITIONS WILL OCCUR ON WEDNESDAY WITH PARTLY CLOUDY
SKIES EXPECTED. IN FACT...MOSTLY CLEAR AND MOSTLY SUNNY SKIES ARE ON
TAP FOR WED NT AND THU.
TEMPS THROUGH THE EXTENDED WILL REMAIN BELOW NORMAL AS A UNIFORM
NORTHERLY FLOW CONTINUES WITH ONLY A VERY SLOW INCREASE IN HEIGHT
VALUES.
IN THE EXTENDED FCST...HEIGHT VALUES WILL CONTINUE TO INCREASE WITH
A RIDGE AXIS REACHING THE AREA ON SATURDAY. THIS WILL EQUATE TO DRY
CONDITIONS AND A WARMING TREND. LATE IN THE EXTENDED HOWEVER...A
COLD FRONT WILL BRING AN INCREASE IN CLOUDINESS AND A LOW CHANCE OF
SHOWER ACTIVITY ON MONDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
330 AM CST TUE DEC 9 2014
.DISCUSSION...
UPPER LEVEL SYSTEM OVER INDIANA WILL DROP SOUTHEASTWARD THIS
MORNING AND WILL MOVE ACROSS EASTERN TN THIS AFTERNOON. THOUGH THE
BETTER DEFORMATIONAL INFLUENCES WILL BE TO THE LEFT OF THE
TRACK...WE DO PICK UP SOME DESCENT CURVATURE AND SHEAR ON THE
RIGHT SIDE OF THE TRACK. LATEST SATELLITE IMAGERY SHOWS THE LOWER
TO MID LEVEL CLOUDINESS TO OUR NORTH ACROSS IL...IN AND NRN MO.
LATEST HRRR AND MODEL DATA BOTH CONCUR WITH SCATTERED LIGHT SHOWER
ACTIVITY ACROSS THE EASTERN PORTIONS OF THE MID STATE THROUGH
TODAY AND INTO TONIGHT. AN EXAMINATION OF FREEZING LEVELS DOES
SUPPORT SNOW FOR AREAS GENERALLY ABOVE 1500 FT MSL AFT 18Z TODAY.
BY 00Z THE ENTIRE EASTERN THIRD OF THE MID STATE...WHERE THE
CHANCES OF PRECIP EXISTS...WILL BE SNOW. AMOUNTS LOOK VERY LIGHT
AND NO ADVISORIES OR SPS PRODUCTS ARE NEEDED. FURTHERMORE...SFC
TEMPS SHOULD GENERALLY REMAIN ABOVE FREEZING UNTIL LATE TONIGHT.
A LOW CHANCE OF SNOWFALL WILL CONTINUE ACROSS THE EAST FOR TONIGHT
BUT AMOUNTS AGAIN WILL BE LIGHT.
FOR THE FCST...WILL INCLUDE A CHANCE OF RAIN AND SNOW EASTERN THIRD
FOR THIS MORNING...JUST RAIN SOUTHEAST. THIS AFTERNOON...WILL TREND
THE GRIDS TOWARD A CHANCE OF ALL SNOW FOR THE EASTERN AREA BY
EVENING. 850 MB TEMPS WILL BE WELL BELOW 0C AND FREEZING LEVELS
WILL BE DROPPING AS WELL AS SFC TEMPS WHICH WILL BE FALLING
THROUGH THE 30S.
IMPROVING CONDITIONS WILL OCCUR ON WEDNESDAY WITH PARTLY CLOUDY
SKIES EXPECTED. IN FACT...MOSTLY CLEAR AND MOSTLY SUNNY SKIES ARE ON
TAP FOR WED NT AND THU.
TEMPS THROUGH THE EXTENDED WILL REMAIN BELOW NORMAL AS A UNIFORM
NORTHERLY FLOW CONTINUES WITH ONLY A VERY SLOW INCREASE IN HEIGHT
VALUES.
IN THE EXTENDED FCST...HEIGHT VALUES WILL CONTINUE TO INCREASE WITH
A RIDGE AXIS REACHING THE AREA ON SATURDAY. THIS WILL EQUATE TO DRY
CONDITIONS AND A WARMING TREND. LATE IN THE EXTENDED HOWEVER...A
COLD FRONT WILL BRING AN INCREASE IN CLOUDINESS AND A LOW CHANCE OF
SHOWER ACTIVITY ON MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 43 32 43 29 / 10 05 05 05
CLARKSVILLE 42 30 42 27 / 10 05 05 05
CROSSVILLE 40 29 39 26 / 30 30 10 05
COLUMBIA 44 31 44 29 / 10 05 05 05
LAWRENCEBURG 45 30 44 27 / 10 05 05 05
WAVERLY 43 31 42 27 / 10 05 05 05
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
310 PM MST TUE DEC 9 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE OVER ARIZONA WILL SWEEP ACROSS THE AREA
TONIGHT AND TOMORROW...BRINGING WIDELY SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS TO THE REGION. DRY CONDITIONS WILL RETURN
FOR THURSDAY AND FRIDAY. TEMPERATURES WILL REMAIN WARM WITH HIGHS
IN THE UPPER 60S FOR THE LOWLANDS. A STRONGER STORM SYSTEM WILL
AFFECT THE AREA SATURDAY AND SUNDAY...BRINGING MOUNTAIN SNOW AND
LOWLAND RAIN SHOWERS TO THE AREA...ALONG WITH WINDY CONDITIONS.
&&
.DISCUSSION...
OUR SO-CALLED WEAK UPPER LEVEL DISTURBANCE HAS WOUND ITSELF UP
PRETTY TIGHTLY INTO A CLOSED H5 LOW OVER ARIZONA...WITH A FAIRLY
POTENT SHORTWAVE TROUGH/VORT MAX OUT AHEAD OF IT MOVING INTO SW
NEW MEXICO THIS AFTERNOON. FAIRLY STEEP MID-LEVEL LAPSE RATES HAVE
RESULTED IN MUCAPE VALUES OF AROUND 500 J/KG...AND THE RESULT HAS
BEEN DECEMBER THUNDERSTORMS OVER SW NEW MEXICO. THE STRONGEST
STORMS AND BEST COVERAGE HAS BEEN OVER THE GILA REGION...BUT NEW
STORMS ARE GOING UP IN CHIHUAHUA JUST TO THE SW OF SANTA TERESA.
RADAR HAD INDICATED A FINE-LINE IN THIS AREA...AND WE ARE
BEGINNING TO SEE PVA AHEAD OF THE LEADING VORT MAX.
LOW WET BULB ZERO HEIGHTS (IT IS DECEMBER AFTER ALL) WILL RESULT
IN SMALL HAIL... MAYBE EVEN UP TO HALF-INCH DIAMETER IN
STRONGER/HIGHER ELEVATION STORMS.
THE INSTABILITY AXIS WILL SHIFT EAST TOWARDS EL PASO OVERNIGHT...
AND WHILE NAM/GFS POPS REMAIN SPOTTY...NEITHER MODEL HAS HANDLED
PRECIP WITH THIS SYSTEM WELL. HAVE RAISED POPS INTO SCATTERED
CATEGORY THIS EVENING FOR THE EL PASO-LAS CRUCES CORRIDOR AND
POINTS EAST. THIS IS ALSO SUPPORTED BY SEVERAL HIGH-RES WRF
MODELS. THE HRRR HAS BEEN SOMEWHAT INCONSISTENT WITH CONVECTION
BUT SUGGESTS A FLARE-UP IN EASTERN OTERO AND HUDSPETH COUNTIES
OVERNIGHT AS WELL.
DRIER AIR ALOFT WILL LIMIT PRECIP CHANCES HEADING INTO TOMORROW.
BUT ISOLATED SHOWERS WILL REMAIN A RISK OVER CENTRAL AND EASTERN
PARTS OF THE FORECAST AREA AS THE UPPER LOW OPENS UP AND SHIFTS
EAST OF THE AREA.
TEMPERATURES WILL REMAIN SEVERAL DEGREES ABOVE NORMAL THROUGH THE
WEEK. ALMOST AS IMPRESSIVE AS THE THUNDERSTORMS WAS THE FACT THAT
WE MANAGED TO REACH THE UPPER-60S AT EL PASO DESPITE THICK HIGH
AND MID-LEVEL CLOUD COVER TODAY. EXPECT THE SAME HEADING INTO THE
WEEKEND AS HIGH AMPLITUDE UPPER RIDGE MOVES ACROSS THE AREA.
THIS HIGH AMPLITUDE PATTERN WILL CONTINUE FOR THE FORESEEABLE
FUTURE. ANOTHER DEEP TROUGH WILL MOVE INTO THE DESERT SOUTHWEST
WITH A CLOSED LOW FORMING OVER ARIZONA SATURDAY NIGHT. THE 12Z GFS
AND 00Z ECMWF HAVE SHIFTED A LITTLE FURTHER SOUTH WITH THE LOW
TRACK...NOW TAKING IT JUST NORTH OF EL PASO...WITH THE 12Z ECMWF A
LITTLE FURTHER NORTH AND RUNNING A LITTLE FASTER. THINGS ARE
LOOKING A LITTLE MORE FAVORABLE FOR MOUNTAIN SNOW WITH THIS
SYSTEM... ESPECIALLY OVER THE SACRAMENTOS...WITH SPOTTIER LOWLAND
PRECIP...MAINLY SATURDAY INTO SATURDAY NIGHT. EXPECT BREEZY TO
WINDY CONDITIONS OVER THE LOWLANDS AS WELL...WINDS WILL BE WEST
WHICH IS NOT IDEAL FOR LOW-LEVEL MOISTURE TRANSPORT...THUS LIMITED
QPF IS EXPECTED IN THE LOWLANDS.
&&
.AVIATION...VALID 09/00Z - 10/00Z...
A MINOR UPPER LEVEL DISTURBANCE WILL MOVE INTO SRN NMEX
TONIGHT/TUESDAY. 00Z-14Z: SCT-BKN120-160 BKN-OVC250. SE WINDS 3-8
KTS. 14Z-24Z: FEW-SCT060 BKN100-140 BKN-0VC200. WINDS ESE 5-10
KTS.
&&
.FIRE WEATHER...
A FAIRLY PROGRESSIVE UPPER AIR PATTERN WILL BRING A SERIES OF
TROUGHS ACROSS THE REGION THIS WEEK. DRY AND CONTINUED MILD
WEATHER CONDITIONS WITH INCREASING HIGH CLOUDINESS WILL OCCUR
TODAY AND TONIGHT. A WEAK UPPER LEVEL DISTURBANCE COMBINED WITH A
SURGE OF MOISTURE FROM THE SOUTHEAST WILL GENERATE A CHANCE OF
LIGHT RAIN SHOWERS FOR MUCH OF THE AREA TUESDAY THROUGH WEDNESDAY
MORNING. DRY CONDITIONS WITH CONTINUED WARM TEMPERATURES WILL
OCCUR THURSDAY AND FRIDAY. A LARGER AND STRONGER PACIFIC STORM
SYSTEM WILL BRING A CHANCE OF LOWLAND RAIN AND MOUNTAIN SNOW
SHOWERS TO THE AREA NEXT SATURDAY AND SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 45 68 46 68 45 / 30 10 0 0 0
SIERRA BLANCA 42 65 42 65 41 / 40 20 0 0 0
LAS CRUCES 42 67 41 68 40 / 30 10 0 0 0
ALAMOGORDO 39 67 39 67 39 / 30 20 0 0 0
CLOUDCROFT 31 51 30 51 34 / 30 20 0 0 0
TRUTH OR CONSEQUENCES 39 64 38 63 37 / 30 10 0 0 0
SILVER CITY 40 62 39 61 39 / 20 10 0 0 0
DEMING 40 67 37 66 37 / 20 0 0 0 0
LORDSBURG 39 67 36 64 37 / 10 0 0 0 0
WEST EL PASO METRO 48 67 48 67 45 / 30 10 0 0 0
DELL CITY 37 65 37 64 38 / 40 10 0 0 0
FORT HANCOCK 44 70 44 70 42 / 30 10 0 0 0
LOMA LINDA 43 64 44 63 43 / 30 10 0 0 0
FABENS 41 68 40 68 41 / 30 10 0 0 0
SANTA TERESA 42 67 42 67 41 / 20 10 0 0 0
WHITE SANDS HQ 44 67 45 68 44 / 30 10 0 0 0
JORNADA RANGE 37 67 36 67 35 / 30 10 0 0 0
HATCH 39 67 39 66 37 / 20 10 0 0 0
COLUMBUS 43 66 42 65 40 / 20 0 0 0 0
OROGRANDE 43 66 43 66 42 / 40 10 0 0 0
MAYHILL 38 59 35 59 38 / 30 20 0 0 0
MESCALERO 32 58 30 58 35 / 30 20 0 0 0
TIMBERON 34 58 34 58 36 / 30 20 0 0 0
WINSTON 34 60 35 59 34 / 30 10 0 0 0
HILLSBORO 40 64 41 63 39 / 30 10 0 0 0
SPACEPORT 35 66 34 65 35 / 20 10 0 0 0
LAKE ROBERTS 35 62 34 60 35 / 30 10 0 0 0
HURLEY 38 63 37 62 36 / 20 10 0 0 0
CLIFF 35 67 33 65 34 / 20 0 0 0 0
MULE CREEK 26 66 25 64 29 / 10 0 0 0 0
FAYWOOD 41 62 41 61 39 / 20 10 0 0 0
ANIMAS 39 70 37 68 38 / 10 0 0 0 0
HACHITA 37 68 34 67 35 / 10 0 0 0 0
ANTELOPE WELLS 39 70 36 69 35 / 10 0 0 0 0
CLOVERDALE 40 69 38 67 38 / 10 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
25-HARDIMAN/20-NOVLAN
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1204 PM CST TUE DEC 9 2014
.AVIATION...
/18Z TAFS/
CHALLENGES IN THE NEAR TERM WILL CONTINUE TO BE THE RESIDUAL AREAS
OF DENSE FOG ACROSS NORTH AND CENTRAL TEXAS THIS MORNING. AS
AMBIENT TEMPERATURES CONTINUE TO WARM THE NEXT FEW HOURS...EROSION
OF THE FOG BANK SHOULD OCCUR QUICKLY AND BRING AN END TO THE FOG
COMPLETELY FOR TODAY.
THE SURFACE HIGH PRESSURE RIDGE ACROSS THE AREA WILL SLOWLY SHIFT
EAST TOWARD THE ARKLATEX THROUGH TONIGHT. IFR/TEMPO LIFR CONDITIONS
WILL PERSIST THE FIRST HOUR...THEN EVENTUALLY GIVE WAY TO MOSTLY
SUNNY AND VFR CONDITIONS BY MID AFTERNOON.
WARMER TEMPERATURES AND INCREASE IN HIGH LEVEL CLOUDS SHOULD STALL
THE FOG FORMATION UNTIL AFTER MIDNIGHT TONIGHT. THE WIND DIRECTION
WILL VEER TO THE EAST/SOUTHEAST...BUT SPEEDS ARE EXPECTED TO REMAIN
VERY LIGHT. BUFR SOUNDINGS INDICATE SHALLOW MOISTURE IN THE NEAR-
SURFACE LAYER WHICH SHOULD RESULT IN MORE IFR AND POSSIBLY LIFR
CONDITIONS BEFORE SUNRISE WEDNESDAY. SOUTHEAST WINDS WILL INCREASE
TO NEAR 10 KTS BY LATE MORNING WEDNESDAY WITH WARMER TEMPERATURES
AND BETTER POTENTIAL TO MIX OUT FOG QUICKER THAN TODAY. THERE IS
A POSSIBILITY FOR A BRIEF DURATION OF DENSE FOG AND VLIFR CONDITIONS
AROUND SUNRISE...THOUGH WILL STAY CONSERVATIVE THIS FAR OUT IN THE
FORECAST WITH AN UPPER LEVEL SYSTEM APPROACHING AND HIGH CLOUDS
INCREASING ACROSS THE AREA.
WE WILL ADVERTISE PREVAILING IFR VSBYS/LIFR CIGS AT THIS TIME FROM
MIDNIGHT THROUGH MID MORNING WEDNESDAY AND ALLOW LATER FORECASTS
TO FINE TUNE FOR MORE LIMITED CONDITIONS IF THEY BECOME MORE
APPARENT LATER TODAY AND THIS EVENING ON SOUNDINGS AND MOS GUIDANCE.
05/
&&
.PREV DISCUSSION... /ISSUED 356 AM CST TUE DEC 9 2014/
AS OF 3 AM...WIDESPREAD DENSE FOG HAS SETTLED IN OVER ALL BUT THE
SOUTHERN ZONES WHERE HIGH CLOUDS WERE IMPEDING RADIATIVE HEAT LOSS
A BIT. STILL WE EXPECT FOG TO CONTINUE TO EXPAND SOUTHWARD BEFORE
SUNRISE. ACROSS THE NORTHERN 2/3RDS OF THE CWA...CONDITIONS ARE
EXTREMELY FAVORABLE FOR DENSE FOG AND IT IS LIKELY THAT IT WILL
BE SLOWER THAN USUAL TO LIFT AND BURN OFF. THE DENSE FOG ADVISORY
EXPIRES AT 10AM...BUT IT MAY NEED TO BE EXTENDED AN HOUR OR TWO
FROM I-20 NORTH. WINDS BELOW 850MB THIS MORNING ARE EXPECTED TO BE
VERY LIGHT...IF NOT NEARLY CALM...WHICH MEANS THE LOW ANGLE
DECEMBER SUN WILL BE THE ONLY THING WORKING TO LIFT THE FOG AND
LOW CLOUDS TODAY. CLOUDS WILL BE SLOWEST TO ERODE TODAY FROM
ROUGHLY I-20 TO THE RED RIVER...BUT OUT OF ALL OF THE MODEL
GUIDANCE...ONLY THE RUC HAS THESE CLOUDS HANGING IN THROUGH EARLY
AFTERNOON. OBVIOUSLY THE EXACT EROSION OF THE LOW CLOUDS WILL HAVE
HUGE IMPLICATIONS ON HIGH TEMPS TODAY...BUT AM LEANING TOWARD THE
RUC SOLUTION AND WILL KEEP TEMPS SEVERAL DEGREES BELOW TRADITIONAL
GUIDANCE FROM I-20 NORTHWARD. IF AND WHERE CLOUDS HOLD IN ALL
AFTERNOON...HIGHS WILL LIKELY ONLY BE IN THE LOWER 50S.
INCREASING MID-HIGH LEVEL MOISTURE/CLOUDS TONIGHT WILL LIMIT
RADIATIONAL COOLING AT THE SURFACE WHICH SHOULD NIX THE DENSE FOG
POTENTIAL. THIS MOISTURE WILL BE ARRIVING IN ADVANCE OF A WELL
DEFINED SHORTWAVE TROUGH THAT IS CURRENTLY NEAR BAJA. WHILE THIS
SYSTEM IS FORECAST TO WEAKEN AS IT ENTERS MORE CONFLUENT FLOW
ACROSS OUR REGION...WATER VAPOR LOOP SHOWS IT HAS TAPPED INTO A
HEALTHY AMOUNT OF MID-UPPER LEVEL PACIFIC MOISTURE AND IS SLINGING
IT INTO TEXAS. THE ECMWF/NAM ARE THE MOST AGGRESSIVE WITH
INCREASING MOISTURE PROFILES OVER OUR REGION WEDNESDAY AND
WEDNESDAY NIGHT...AND GIVEN THE LATEST SATELLITE TRENDS AM
INCLINED TO BELIEVE THEM. THEREFORE HAVE INCREASED THE CHANCES FOR
LIGHT RAIN SHOWERS WEDNESDAY AND INTO THURSDAY. THERE WILL BE A
LAYER OF DRIER AIR BELOW THIS MOISTURE THAT WILL KEEP PRECIP FROM
REACHING THE GROUND WEDNESDAY...BUT THIS LAYER SHOULD SATURATE
FROM TOP DOWN BY WEDNESDAY NIGHT. WE HAVE INTRODUCED SPRINKLES
INTO THE FORECAST WEDNESDAY AFTERNOON...AS MEASURABLE PRECIP WILL
BE UNLIKELY INITIALLY. THE BEST CHANCES OF MEASURABLE RAIN WILL
OCCUR WEDNESDAY NIGHT AND THURSDAY AND PRIMARILY OVER THE SOUTHERN
HALF OF THE CWA WHERE A TINY AMOUNT OF MID LEVEL INSTABILITY WILL
BE AVAILABLE. QPF WILL BE LOW WITH THIS SYSTEM AND WE EXPECT LESS
THAN 1/10 OF AN INCH. HIGHS WEDNESDAY AND THURSDAY LOOK TO REMAIN
SEASONABLY COOL AS THICK CLOUD COVER WILL INHIBIT DAYTIME WARMING.
AS THE SYSTEM EXITS THURSDAY EVENING...THE MID TO UPPER LEVELS
WILL DRY OUT SUBSTANTIALLY. HOWEVER THE LOW LEVELS WILL REMAIN
MOIST AND NEARLY SATURATED...WHICH WILL PROMOTE CONTINUED MOSTLY
CLOUDY SKIES WITH JUST A SLOW WARMING TREND INTO THE WEEKEND.
SOUTHERLY WINDS INCREASE SATURDAY AHEAD OF A STRONG UPPER LEVEL
TROUGH THAT WILL MOVE INTO THE FOUR CORNERS REGION. WHILE MODEL
GUIDANCE CONTINUES TO SHOW AN UPPER LEVEL LOW CLOSING OFF AT THE
BASE OF THE TROUGH...THEY HAVE SHIFTED THE TRACK FARTHER TO THE
NORTH THAN YESTERDAY/S MODEL RUNS. STILL...THE TRACK OF THIS
SYSTEM WOULD PLACE NORTH TEXAS IN A REGION OF STRONG DYNAMIC LIFT
AND GIVEN THE AMPLE LOW LEVEL MOISTURE ALREADY IN PLACE THIS
SHOULD RESULT IN A GOOD CHANCE OF WIDESPREAD RAIN SUNDAY AND/OR
SUNDAY NIGHT. WHILE SHEAR PROFILES ARE STRONG...SURFACE
INSTABILITY LOOKS TO BE VERY LIMITED AND SHOULD LIMIT THE SEVERE
WEATHER THREAT. 925MB THETA-E VALUES DO SUPPORT ENOUGH INSTABILITY
FOR THE INCLUSION OF THUNDERSTORMS IN THE FORECAST BUT MUCAPE
LOOKS TO BE LESS THAN 500 J/KG. RAIN CHANCES SHOULD END FROM WEST
TO EAST SUNDAY NIGHT WITH THE PASSAGE OF A COLD FRONT. TEMPS
WILL COOL BACK TO NEAR NORMAL FOR MONDAY...BUT WRAP-AROUND LOW
CLOUDS MAY KEEP MONDAY/S HIGHS COOLER THAN CURRENTLY ADVERTISED.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 44 61 51 59 / 0 5 10 20 20
WACO, TX 62 42 60 51 63 / 0 5 20 30 30
PARIS, TX 60 39 55 43 55 / 0 5 5 20 20
DENTON, TX 57 40 60 49 58 / 0 5 10 20 20
MCKINNEY, TX 58 39 59 48 58 / 0 5 10 20 20
DALLAS, TX 59 45 60 50 60 / 0 5 10 20 20
TERRELL, TX 60 42 60 48 59 / 0 5 10 20 20
CORSICANA, TX 61 44 62 50 59 / 0 5 10 30 30
TEMPLE, TX 64 45 62 52 64 / 0 5 20 30 30
MINERAL WELLS, TX 61 42 59 51 62 / 0 5 10 20 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR TXZ091>095-100>107-
115>123-129>135-141>148-156>162-174-175.
&&
$$
05/69
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1130 AM CST TUE DEC 9 2014
.AVIATION...
VFR CONDITIONS IN PLACE AND WILL REMAIN IN PLACE UNTIL AROUND
MIDNIGHT LOCAL TIME. AFTER THIS...AMPLE LOW LEVEL MOISTURE AND
LIGHT WIND WILL RESULT IN AREAS OF MVFR/IFR CEILINGS AT ALL TAF
SITES. AFTER MIDNIGHT...EXPECT CONDITIONS TO DROP DOWN INTO
IFR/LIFR RANGE WITH THE POTENTIAL FOR VLIFR AT ALL THREE
TERMINALS. CONFIDENCE IS INCREASING FOR THE DEVELOPMENT OF VLIFR
RANGE AND OPTED TO GO PREVAILING AT KLBB AND KPVW. THERE COULD BE
SOME DIFFERENCES IN TIMING AS WE GET CLOSER TO TONIGHT SO
ADJUSTMENTS MAY BE NECESSARY. LIFR CONDITIONS WILL LAST THROUGH
THE BETTER PART OF THE MORNING BEFORE WE SEE SOME IMPROVEMENT
AROUND 18Z TOMORROW.
JORDAN
&&
.PREV DISCUSSION... /ISSUED 530 AM CST TUE DEC 9 2014/
AVIATION...
THICK FOG CONTINUES IN AND OUT AT KCDS MAKING TAF FORECASTING A
BIT TEDIOUS. AT KLBB AND KPVW...WE EXPECT A LIGHT FOG TO ENVELOPE
THE AREA THROUGH MID MORNING THOUGH ALSO CANNOT COMPLETELY RULE OUT
DENSE FOG AS WELL. LATEST HRRR SOLUTIONS CONTINUE TO INSIST ON A
RISK OF VERY LOW VISIBILITY AT KLBB AND KPVW WHILE THE MUCH LARGER
DENSE FOG AREA CONTINUES ON THE HRRR RUNS FROM NEAR CHILDRESS TO
THE EAST AND SOUTH. SHOULD IMPROVE BOTH SITES TO IFR BY MID TO
LATE MORNING WITH ONLY HIGH CLOUDS MUCH OF THE DAY. TONIGHT WE
EXPECT A THICK BATCH OF LOW LEVEL MOISTURE TO SPREAD NORTHWARD
THROUGH KLBB AND POSSIBLY KCDS. TENTATIVE FORECAST FOR 18 HOURS
AND BEYOND WILL INDICATE PREVAILING MVFR CONDITIONS AT KPVW AND
KLBB. A RISK FOR MUCH WORSE CONDITIONS EXISTS BY 12Z WEDNESDAY BUT
WILL LEAVE DETAILS TO LATER FORECASTS. RMCQUEEN
PREV DISCUSSION... /ISSUED 331 AM CST TUE DEC 9 2014/
SHORT TERM...
A WEAK UPPER TROUGH CROSSING ARIZONA TODAY WILL EDGE INTO THE
SOUTHERN ROCKIES TONIGHT. MEAGER UPPER LEVEL LIFT WILL EDGE TOWARDS
THE WESTERN SOUTH PLAINS LATER TONIGHT WHILE A MASS OF 800MB TO
900MB MOISTURE WILL EXPAND ACROSS AREAS ON THE CAPROCK ESPECIALLY.
ALTHOUGH COUPLING WITH THE UPPER TROUGH IS NOT APPARENT...WE THINK
THERE COULD BE ADEQUATE LOW LEVEL LIFT TO SUPPORT A SLIGHT CHANCE OF
SHOWERS MAINLY IN THE WEST OR SOUTHWESTERN PART OF THE SOUTH PLAINS.
AND THIS LOW LEVEL MOISTURE INCREASE SHOULD FUEL ANOTHER BOUT OF FOG
FROM THE CAPROCK ACROSS THE SOUTHEAST PANHANDLE. INCREASE IN HIGH
CLOUDS TODAY SHOULD KNOCK A CATEGORY OFF HIGHS TODAY FROM YESTERDAY.
THE MOISTURE INCREASE TONIGHT SHOULD HOLD MINIMUMS QUITE A BIT ABOVE
NORMAL. PLAN TO MAINTAIN THIS MORNINGS DENSE FOG ADVISORY FOR SOME
PORTION OF THE ROLLING PLAINS...WILL ADD OR RETRACT AREAS AS NEEDED.
RMCQUEEN
LONG TERM...
THE WEAK UPPER LEVEL TROUGH MOVING TOWARDS THE AREA WILL PASS OVER
WEST TEXAS ON WEDNESDAY BUT WILL CONTINUE TO BRING MEAGER CHANCES
OF PRECIPITATION. A GOOD FETCH OF MID AND HIGH LEVEL MOISTURE IS
OBSERVED WITH THIS SHORT WAVE ON WATER VAPOR IMAGERY. GOOD LOW
LEVEL MOISTURE WILL REMAIN IN PLACE BUT WE WILL STILL HAVE TO
CONTEND WITH A NOTICEABLE DRY LAYER AROUND 700MB SIMILAR TO THE
SHORT WAVE TROUGH FROM A FEW DAYS AGO. WITH SUCH WEAK LIFT
ASSOCIATED WITH THIS SHORT WAVE NOT MUCH MORE THAN SPRINKLES OR
VERY LIGHT RAIN SHOWERS WILL BE LIKELY. WITHOUT ANY SIGNIFICANT
TROUGHS OR COLD FRONTS...LOW LEVEL MOISTURE WILL REMAIN ABUNDANT
THROUGH AT LEAST FRIDAY. DEW POINTS WILL BE INCREDIBLY HIGH FOR
DECEMBER AND MAY LEAD TO FOG EVERY MORNING THROUGH FRIDAY.
THE WEATHER CONDITIONS WILL CHANGE OVER THE WEEKEND WITH THE
APPROACH OF A MORE SIGNIFICANT TROUGH. MODELS ARE IN GOOD
AGREEMENT BUT CONTINUE TO BOUNCE AROUND WITH EACH MODEL
ITERATION. ENSEMBLES CONFIRM THE UNCERTAINTY WITH HIGH SPREAD IN
THE THEIR SOLUTIONS. UNFORTUNATELY...THIS SYSTEM IS TRENDING
PROGRESSIVE WITH ONLY A QUICK SHOT OF PRECIPITATION FROM SATURDAY
NIGHT INTO SUNDAY. LEE TROUGHING AHEAD OF THIS SYSTEM ON FRIDAY
AND SATURDAY WILL LEAD TO MORE FAMILIAR WARM...DRY...AND BREEZY
CONDITIONS. ALTHOUGH THE LARGE CAVEAT IN ALL OF THIS IS THAT THIS
SYSTEM IS STILL AROUND 3500 MILES AWAY OVER THE NORTH-CENTRAL
PACIFIC.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 62 42 58 37 65 / 0 10 10 10 0
TULIA 63 43 59 41 64 / 0 10 10 10 10
PLAINVIEW 64 43 59 40 64 / 0 10 10 10 10
LEVELLAND 63 47 60 42 64 / 0 10 10 10 10
LUBBOCK 63 46 60 42 65 / 0 10 10 10 10
DENVER CITY 63 47 59 42 63 / 0 10 10 10 10
BROWNFIELD 63 47 59 44 63 / 0 10 10 10 10
CHILDRESS 63 42 61 46 65 / 0 10 10 10 10
SPUR 64 46 62 47 64 / 0 10 10 10 10
ASPERMONT 64 45 63 49 65 / 0 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
624 AM CST TUE DEC 9 2014
.AVIATION...
...WIDESPREAD DENSE FOG EVENT UNDERWAY ACROSS MANY NORTH TEXAS AIRPORTS...
PRIMARY CHALLENGE THIS MORNING WILL BE TIMING THE DISSIPATION OF
LIFR AND IFR CEILINGS AND VISIBILITIES. OBSERVATIONS AT ALL 6 TAF
SITES INDICATED DENSE FOG WITH VISIBILITY VALUES AT OR BELOW ONE
QUARTER MILE. EVEN THOUGH THE FOG IS RELATIVELY SHALLOW...THE
DISSIPATION PROCESS IS LIKELY TO BE SLOW GIVEN THE VERY LIGHT LOW
LEVEL WINDS...TIME OF YEAR...AND THE WIDESPREAD NATURE OF THE
SURFACE-BASED CLOUD DECK.
EXPECT A RAPID IMPROVEMENT IN VISIBILITY AFTER 15Z /9 AM
CST/...BUT THE SUBSEQUENT IFR CEILINGS ARE LIKELY TO PERSIST UNTIL
18Z OR 19Z.
SURFACE WINDS WILL BE LIGHT AND VARIABLE THROUGH THE PERIOD AS
SURFACE RIDGE MOVES ACROSS THE REGION TODAY.
A REPEAT OF THE WIDESPREAD DENSE FOG IS NOT EXPECTED TONIGHT /
WEDNESDAY MORNING SINCE MID AND HIGH LEVEL CLOUD COVER WILL
INHIBIT RADIATIONAL COOLING.
09/GP
&&
.PREV DISCUSSION... /ISSUED 356 AM CST TUE DEC 9 2014/
AS OF 3 AM...WIDESPREAD DENSE FOG HAS SETTLED IN OVER ALL BUT THE
SOUTHERN ZONES WHERE HIGH CLOUDS WERE IMPEDING RADIATIVE HEAT LOSS
A BIT. STILL WE EXPECT FOG TO CONTINUE TO EXPAND SOUTHWARD BEFORE
SUNRISE. ACROSS THE NORTHERN 2/3RDS OF THE CWA...CONDITIONS ARE
EXTREMELY FAVORABLE FOR DENSE FOG AND IT IS LIKELY THAT IT WILL
BE SLOWER THAN USUAL TO LIFT AND BURN OFF. THE DENSE FOG ADVISORY
EXPIRES AT 10AM...BUT IT MAY NEED TO BE EXTENDED AN HOUR OR TWO
FROM I-20 NORTH. WINDS BELOW 850MB THIS MORNING ARE EXPECTED TO BE
VERY LIGHT...IF NOT NEARLY CALM...WHICH MEANS THE LOW ANGLE
DECEMBER SUN WILL BE THE ONLY THING WORKING TO LIFT THE FOG AND
LOW CLOUDS TODAY. CLOUDS WILL BE SLOWEST TO ERODE TODAY FROM
ROUGHLY I-20 TO THE RED RIVER...BUT OUT OF ALL OF THE MODEL
GUIDANCE...ONLY THE RUC HAS THESE CLOUDS HANGING IN THROUGH EARLY
AFTERNOON. OBVIOUSLY THE EXACT EROSION OF THE LOW CLOUDS WILL HAVE
HUGE IMPLICATIONS ON HIGH TEMPS TODAY...BUT AM LEANING TOWARD THE
RUC SOLUTION AND WILL KEEP TEMPS SEVERAL DEGREES BELOW TRADITIONAL
GUIDANCE FROM I-20 NORTHWARD. IF AND WHERE CLOUDS HOLD IN ALL
AFTERNOON...HIGHS WILL LIKELY ONLY BE IN THE LOWER 50S.
INCREASING MID-HIGH LEVEL MOISTURE/CLOUDS TONIGHT WILL LIMIT
RADIATIONAL COOLING AT THE SURFACE WHICH SHOULD NIX THE DENSE FOG
POTENTIAL. THIS MOISTURE WILL BE ARRIVING IN ADVANCE OF A WELL
DEFINED SHORTWAVE TROUGH THAT IS CURRENTLY NEAR BAJA. WHILE THIS
SYSTEM IS FORECAST TO WEAKEN AS IT ENTERS MORE CONFLUENT FLOW
ACROSS OUR REGION...WATER VAPOR LOOP SHOWS IT HAS TAPPED INTO A
HEALTHY AMOUNT OF MID-UPPER LEVEL PACIFIC MOISTURE AND IS SLINGING
IT INTO TEXAS. THE ECMWF/NAM ARE THE MOST AGGRESSIVE WITH
INCREASING MOISTURE PROFILES OVER OUR REGION WEDNESDAY AND
WEDNESDAY NIGHT...AND GIVEN THE LATEST SATELLITE TRENDS AM
INCLINED TO BELIEVE THEM. THEREFORE HAVE INCREASED THE CHANCES FOR
LIGHT RAIN SHOWERS WEDNESDAY AND INTO THURSDAY. THERE WILL BE A
LAYER OF DRIER AIR BELOW THIS MOISTURE THAT WILL KEEP PRECIP FROM
REACHING THE GROUND WEDNESDAY...BUT THIS LAYER SHOULD SATURATE
FROM TOP DOWN BY WEDNESDAY NIGHT. WE HAVE INTRODUCED SPRINKLES
INTO THE FORECAST WEDNESDAY AFTERNOON...AS MEASURABLE PRECIP WILL
BE UNLIKELY INITIALLY. THE BEST CHANCES OF MEASURABLE RAIN WILL
OCCUR WEDNESDAY NIGHT AND THURSDAY AND PRIMARILY OVER THE SOUTHERN
HALF OF THE CWA WHERE A TINY AMOUNT OF MID LEVEL INSTABILITY WILL
BE AVAILABLE. QPF WILL BE LOW WITH THIS SYSTEM AND WE EXPECT LESS
THAN 1/10 OF AN INCH. HIGHS WEDNESDAY AND THURSDAY LOOK TO REMAIN
SEASONABLY COOL AS THICK CLOUD COVER WILL INHIBIT DAYTIME WARMING.
AS THE SYSTEM EXITS THURSDAY EVENING...THE MID TO UPPER LEVELS
WILL DRY OUT SUBSTANTIALLY. HOWEVER THE LOW LEVELS WILL REMAIN
MOIST AND NEARLY SATURATED...WHICH WILL PROMOTE CONTINUED MOSTLY
CLOUDY SKIES WITH JUST A SLOW WARMING TREND INTO THE WEEKEND.
SOUTHERLY WINDS INCREASE SATURDAY AHEAD OF A STRONG UPPER LEVEL
TROUGH THAT WILL MOVE INTO THE FOUR CORNERS REGION. WHILE MODEL
GUIDANCE CONTINUES TO SHOW AN UPPER LEVEL LOW CLOSING OFF AT THE
BASE OF THE TROUGH...THEY HAVE SHIFTED THE TRACK FARTHER TO THE
NORTH THAN YESTERDAY/S MODEL RUNS. STILL...THE TRACK OF THIS
SYSTEM WOULD PLACE NORTH TEXAS IN A REGION OF STRONG DYNAMIC LIFT
AND GIVEN THE AMPLE LOW LEVEL MOISTURE ALREADY IN PLACE THIS
SHOULD RESULT IN A GOOD CHANCE OF WIDESPREAD RAIN SUNDAY AND/OR
SUNDAY NIGHT. WHILE SHEAR PROFILES ARE STRONG...SURFACE
INSTABILITY LOOKS TO BE VERY LIMITED AND SHOULD LIMIT THE SEVERE
WEATHER THREAT. 925MB THETA-E VALUES DO SUPPORT ENOUGH INSTABILITY
FOR THE INCLUSION OF THUNDERSTORMS IN THE FORECAST BUT MUCAPE
LOOKS TO BE LESS THAN 500 J/KG. RAIN CHANCES SHOULD END FROM WEST
TO EAST SUNDAY NIGHT WITH THE PASSAGE OF A COLD FRONT. TEMPS
WILL COOL BACK TO NEAR NORMAL FOR MONDAY...BUT WRAP-AROUND LOW
CLOUDS MAY KEEP MONDAY/S HIGHS COOLER THAN CURRENTLY ADVERTISED.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 44 61 51 59 / 0 5 10 20 20
WACO, TX 62 42 60 51 63 / 0 5 20 30 30
PARIS, TX 60 39 55 43 55 / 0 5 5 20 20
DENTON, TX 57 40 60 49 58 / 0 5 10 20 20
MCKINNEY, TX 58 39 59 48 58 / 0 5 10 20 20
DALLAS, TX 59 45 60 50 60 / 0 5 10 20 20
TERRELL, TX 60 42 60 48 59 / 0 5 10 20 20
CORSICANA, TX 61 44 62 50 59 / 0 5 10 30 30
TEMPLE, TX 64 45 62 52 64 / 0 5 20 30 30
MINERAL WELLS, TX 61 42 59 51 62 / 0 5 10 20 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR TXZ091>095-
100>107-115>123-129>135-141>148-156>162-174-175.
&&
$$
09/
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
530 AM CST TUE DEC 9 2014
.AVIATION...
THICK FOG CONTINUES IN AND OUT AT KCDS MAKING TAF FORECASTING A
BIT TEDIOUS. AT KLBB AND KPVW...WE EXPECT A LIGHT FOG TO ENVELOPE
THE AREA THROUGH MID MORNING THOUGH ALSO CANNOT COMPLETELY RULE OUT
DENSE FOG AS WELL. LATEST HRRR SOLUTIONS CONTINUE TO INSIST ON A
RISK OF VERY LOW VISIBILITY AT KLBB AND KPVW WHILE THE MUCH LARGER
DENSE FOG AREA CONTINUES ON THE HRRR RUNS FROM NEAR CHILDRESS TO
THE EAST AND SOUTH. SHOULD IMPROVE BOTH SITES TO IFR BY MID TO
LATE MORNING WITH ONLY HIGH CLOUDS MUCH OF THE DAY. TONIGHT WE
EXPECT A THICK BATCH OF LOW LEVEL MOISTURE TO SPREAD NORTHWARD
THROUGH KLBB AND POSSIBLY KCDS. TENTATIVE FORECAST FOR 18 HOURS
AND BEYOND WILL INDICATE PREVAILING MVFR CONDITIONS AT KPVW AND
KLBB. A RISK FOR MUCH WORSE CONDITIONS EXISTS BY 12Z WEDNESDAY BUT
WILL LEAVE DETAILS TO LATER FORECASTS. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 331 AM CST TUE DEC 9 2014/
SHORT TERM...
A WEAK UPPER TROUGH CROSSING ARIZONA TODAY WILL EDGE INTO THE
SOUTHERN ROCKIES TONIGHT. MEAGER UPPER LEVEL LIFT WILL EDGE TOWARDS
THE WESTERN SOUTH PLAINS LATER TONIGHT WHILE A MASS OF 800MB TO
900MB MOISTURE WILL EXPAND ACROSS AREAS ON THE CAPROCK ESPECIALLY.
ALTHOUGH COUPLING WITH THE UPPER TROUGH IS NOT APPARENT...WE THINK
THERE COULD BE ADEQUATE LOW LEVEL LIFT TO SUPPORT A SLIGHT CHANCE OF
SHOWERS MAINLY IN THE WEST OR SOUTHWESTERN PART OF THE SOUTH PLAINS.
AND THIS LOW LEVEL MOISTURE INCREASE SHOULD FUEL ANOTHER BOUT OF FOG
FROM THE CAPROCK ACROSS THE SOUTHEAST PANHANDLE. INCREASE IN HIGH
CLOUDS TODAY SHOULD KNOCK A CATEGORY OFF HIGHS TODAY FROM YESTERDAY.
THE MOISTURE INCREASE TONIGHT SHOULD HOLD MINIMUMS QUITE A BIT ABOVE
NORMAL. PLAN TO MAINTAIN THIS MORNINGS DENSE FOG ADVISORY FOR SOME
PORTION OF THE ROLLING PLAINS...WILL ADD OR RETRACT AREAS AS NEEDED.
RMCQUEEN
LONG TERM...
THE WEAK UPPER LEVEL TROUGH MOVING TOWARDS THE AREA WILL PASS OVER
WEST TEXAS ON WEDNESDAY BUT WILL CONTINUE TO BRING MEAGER CHANCES
OF PRECIPITATION. A GOOD FETCH OF MID AND HIGH LEVEL MOISTURE IS
OBSERVED WITH THIS SHORT WAVE ON WATER VAPOR IMAGERY. GOOD LOW
LEVEL MOISTURE WILL REMAIN IN PLACE BUT WE WILL STILL HAVE TO
CONTEND WITH A NOTICEABLE DRY LAYER AROUND 700MB SIMILAR TO THE
SHORT WAVE TROUGH FROM A FEW DAYS AGO. WITH SUCH WEAK LIFT
ASSOCIATED WITH THIS SHORT WAVE NOT MUCH MORE THAN SPRINKLES OR
VERY LIGHT RAIN SHOWERS WILL BE LIKELY. WITHOUT ANY SIGNIFICANT
TROUGHS OR COLD FRONTS...LOW LEVEL MOISTURE WILL REMAIN ABUNDANT
THROUGH AT LEAST FRIDAY. DEW POINTS WILL BE INCREDIBLY HIGH FOR
DECEMBER AND MAY LEAD TO FOG EVERY MORNING THROUGH FRIDAY.
THE WEATHER CONDITIONS WILL CHANGE OVER THE WEEKEND WITH THE
APPROACH OF A MORE SIGNIFICANT TROUGH. MODELS ARE IN GOOD
AGREEMENT BUT CONTINUE TO BOUNCE AROUND WITH EACH MODEL
ITERATION. ENSEMBLES CONFIRM THE UNCERTAINTY WITH HIGH SPREAD IN
THE THEIR SOLUTIONS. UNFORTUNATELY...THIS SYSTEM IS TRENDING
PROGRESSIVE WITH ONLY A QUICK SHOT OF PRECIPITATION FROM SATURDAY
NIGHT INTO SUNDAY. LEE TROUGHING AHEAD OF THIS SYSTEM ON FRIDAY
AND SATURDAY WILL LEAD TO MORE FAMILIAR WARM...DRY...AND BREEZY
CONDITIONS. ALTHOUGH THE LARGE CAVEAT IN ALL OF THIS IS THAT THIS
SYSTEM IS STILL AROUND 3500 MILES AWAY OVER THE NORTH-CENTRAL
PACIFIC.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 62 42 58 37 65 / 0 10 10 10 0
TULIA 63 43 59 41 64 / 0 10 10 10 10
PLAINVIEW 64 43 59 40 64 / 0 10 10 10 10
LEVELLAND 63 47 60 42 64 / 0 10 10 10 10
LUBBOCK 63 46 60 42 65 / 0 10 10 10 10
DENVER CITY 63 47 59 42 63 / 0 10 10 10 10
BROWNFIELD 63 47 59 44 63 / 0 10 10 10 10
CHILDRESS 63 42 61 46 65 / 0 10 10 10 10
SPUR 64 46 62 47 64 / 0 10 10 10 10
ASPERMONT 64 45 63 49 65 / 0 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: TXZ026-032-038-044.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
356 AM CST TUE DEC 9 2014
.DISCUSSION...
AS OF 3 AM...WIDESPREAD DENSE FOG HAS SETTLED IN OVER ALL BUT THE
SOUTHERN ZONES WHERE HIGH CLOUDS WERE IMPEDING RADIATIVE HEAT LOSS
A BIT. STILL WE EXPECT FOG TO CONTINUE TO EXPAND SOUTHWARD BEFORE
SUNRISE. ACROSS THE NORTHERN 2/3RDS OF THE CWA...CONDITIONS ARE
EXTREMELY FAVORABLE FOR DENSE FOG AND IT IS LIKELY THAT IT WILL
BE SLOWER THAN USUAL TO LIFT AND BURN OFF. THE DENSE FOG ADVISORY
EXPIRES AT 10AM...BUT IT MAY NEED TO BE EXTENDED AN HOUR OR TWO
FROM I-20 NORTH. WINDS BELOW 850MB THIS MORNING ARE EXPECTED TO BE
VERY LIGHT...IF NOT NEARLY CALM...WHICH MEANS THE LOW ANGLE
DECEMBER SUN WILL BE THE ONLY THING WORKING TO LIFT THE FOG AND
LOW CLOUDS TODAY. CLOUDS WILL BE SLOWEST TO ERODE TODAY FROM
ROUGHLY I-20 TO THE RED RIVER...BUT OUT OF ALL OF THE MODEL
GUIDANCE...ONLY THE RUC HAS THESE CLOUDS HANGING IN THROUGH EARLY
AFTERNOON. OBVIOUSLY THE EXACT EROSION OF THE LOW CLOUDS WILL HAVE
HUGE IMPLICATIONS ON HIGH TEMPS TODAY...BUT AM LEANING TOWARD THE
RUC SOLUTION AND WILL KEEP TEMPS SEVERAL DEGREES BELOW TRADITIONAL
GUIDANCE FROM I-20 NORTHWARD. IF AND WHERE CLOUDS HOLD IN ALL
AFTERNOON...HIGHS WILL LIKELY ONLY BE IN THE LOWER 50S.
INCREASING MID-HIGH LEVEL MOISTURE/CLOUDS TONIGHT WILL LIMIT
RADIATIONAL COOLING AT THE SURFACE WHICH SHOULD NIX THE DENSE FOG
POTENTIAL. THIS MOISTURE WILL BE ARRIVING IN ADVANCE OF A WELL
DEFINED SHORTWAVE TROUGH THAT IS CURRENTLY NEAR BAJA. WHILE THIS
SYSTEM IS FORECAST TO WEAKEN AS IT ENTERS MORE CONFLUENT FLOW
ACROSS OUR REGION...WATER VAPOR LOOP SHOWS IT HAS TAPPED INTO A
HEALTHY AMOUNT OF MID-UPPER LEVEL PACIFIC MOISTURE AND IS SLINGING
IT INTO TEXAS. THE ECMWF/NAM ARE THE MOST AGGRESSIVE WITH
INCREASING MOISTURE PROFILES OVER OUR REGION WEDNESDAY AND
WEDNESDAY NIGHT...AND GIVEN THE LATEST SATELLITE TRENDS AM
INCLINED TO BELIEVE THEM. THEREFORE HAVE INCREASED THE CHANCES FOR
LIGHT RAIN SHOWERS WEDNESDAY AND INTO THURSDAY. THERE WILL BE A
LAYER OF DRIER AIR BELOW THIS MOISTURE THAT WILL KEEP PRECIP FROM
REACHING THE GROUND WEDNESDAY...BUT THIS LAYER SHOULD SATURATE
FROM TOP DOWN BY WEDNESDAY NIGHT. WE HAVE INTRODUCED SPRINKLES
INTO THE FORECAST WEDNESDAY AFTERNOON...AS MEASURABLE PRECIP WILL
BE UNLIKELY INITIALLY. THE BEST CHANCES OF MEASURABLE RAIN WILL
OCCUR WEDNESDAY NIGHT AND THURSDAY AND PRIMARILY OVER THE SOUTHERN
HALF OF THE CWA WHERE A TINY AMOUNT OF MID LEVEL INSTABILITY WILL
BE AVAILABLE. QPF WILL BE LOW WITH THIS SYSTEM AND WE EXPECT LESS
THAN 1/10 OF AN INCH. HIGHS WEDNESDAY AND THURSDAY LOOK TO REMAIN
SEASONABLY COOL AS THICK CLOUD COVER WILL INHIBIT DAYTIME WARMING.
AS THE SYSTEM EXITS THURSDAY EVENING...THE MID TO UPPER LEVELS
WILL DRY OUT SUBSTANTIALLY. HOWEVER THE LOW LEVELS WILL REMAIN
MOIST AND NEARLY SATURATED...WHICH WILL PROMOTE CONTINUED MOSTLY
CLOUDY SKIES WITH JUST A SLOW WARMING TREND INTO THE WEEKEND.
SOUTHERLY WINDS INCREASE SATURDAY AHEAD OF A STRONG UPPER LEVEL
TROUGH THAT WILL MOVE INTO THE FOUR CORNERS REGION. WHILE MODEL
GUIDANCE CONTINUES TO SHOW AN UPPER LEVEL LOW CLOSING OFF AT THE
BASE OF THE TROUGH...THEY HAVE SHIFTED THE TRACK FARTHER TO THE
NORTH THAN YESTERDAY/S MODEL RUNS. STILL...THE TRACK OF THIS
SYSTEM WOULD PLACE NORTH TEXAS IN A REGION OF STRONG DYNAMIC LIFT
AND GIVEN THE AMPLE LOW LEVEL MOISTURE ALREADY IN PLACE THIS
SHOULD RESULT IN A GOOD CHANCE OF WIDESPREAD RAIN SUNDAY AND/OR
SUNDAY NIGHT. WHILE SHEAR PROFILES ARE STRONG...SURFACE
INSTABILITY LOOKS TO BE VERY LIMITED AND SHOULD LIMIT THE SEVERE
WEATHER THREAT. 925MB THETA-E VALUES DO SUPPORT ENOUGH INSTABILITY
FOR THE INCLUSION OF THUNDERSTORMS IN THE FORECAST BUT MUCAPE
LOOKS TO BE LESS THAN 500 J/KG. RAIN CHANCES SHOULD END FROM WEST
TO EAST SUNDAY NIGHT WITH THE PASSAGE OF A COLD FRONT. TEMPS
WILL COOL BACK TO NEAR NORMAL FOR MONDAY...BUT WRAP-AROUND LOW
CLOUDS MAY KEEP MONDAY/S HIGHS COOLER THAN CURRENTLY ADVERTISED.
TR.92
&&
.AVIATION...
/ISSUED 1148 PM CST MON DEC 8 2014/
CONCERNS...IFR/LIFR CONDITIONS LIKELY OVERNIGHT THROUGH 16Z AS
AREAS OF FOG CONTINUE TO DEVELOP. MVFR CONDITIONS 16Z THROUGH
18-20Z.
AREAS OF FOG DEVELOPED ACROSS NORTH AND CENTRAL TEXAS MONDAY
EVENING. VISIBILITIES HAVE BEEN VARIABLE FALLING BELOW 1 MILE AT
TIMES AND RISING TO 3-5SM. EXPECT VISIBILITIES OVERALL TO FALL TO
1 MILE OR LESS OVERNIGHT THROUGH MID MORNING TUESDAY AT THE TAF
SITES...SO HAVE PLACED 1 SM BR IN MOST OF THE METROPLEX
SITES...WITH A TEMPO 1/2SM 10-14Z. VISIBILITIES WILL LIKELY FALL
TO 1/4 MILE OR LESS AT TIMES BUT FOR NOW WILL JUST LEAVE THE
TEMPO 1/2SM. THE ONE INHIBITING FACTOR FOR DENSE FOG IS THE SHIELD
OF HIGH CLOUDS THAT WILL BE MOVING ACROSS THE REGION THROUGH
TUESDAY. EXPECT THE FOG TO DIMINISH BY LATE TUESDAY MORNING AND
VFR CONDITIONS ARE EXPECTED TO RETURN EARLY TUESDAY AFTERNOON.
WINDS WILL REMAIN LIGHT...MOSTLY NORTH TONIGHT AND NORTHEAST BY
TUESDAY AFTERNOON.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 44 61 51 59 / 0 5 10 20 20
WACO, TX 62 42 60 51 63 / 0 5 20 30 30
PARIS, TX 60 39 55 43 55 / 0 5 5 20 20
DENTON, TX 57 40 60 49 58 / 0 5 10 20 20
MCKINNEY, TX 58 39 59 48 58 / 0 5 10 20 20
DALLAS, TX 59 45 60 50 60 / 0 5 10 20 20
TERRELL, TX 60 42 60 48 59 / 0 5 10 20 20
CORSICANA, TX 61 44 62 50 59 / 0 5 10 30 30
TEMPLE, TX 64 45 62 52 64 / 0 5 20 30 30
MINERAL WELLS, TX 61 42 59 51 62 / 0 5 10 20 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR TXZ091>095-
100>107-115>123-129>135-141>148-156>162-174-175.
&&
$$
/
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
1135 PM CST MON DEC 8 2014
.AVIATION...
/06Z TAFS/
The aviation forecast remains problematic with regard to how
extensive the low stratus and fog development will be overnight
and early Tuesday morning in our forecast area. Goes 11-3.9 micron
satellite imagery, along with confirmation calls to county law
enforcement, indicates dense fog across the far northern part
of our area (Haskell and Throckmorton Counties). Temperature/
dewpoint spreads are decreasing farther south across our area
with radiational cooling, but thicker higher cloud coverage
is also overspreading our area from the west. The increasing
high cloudiness could delay and limit the development of
fog and low stratus overnight. At this time, have higher
confidence that the KABI site will be affected, and have
conditions degrading to low end IFR conditions at that site
after 08Z. Elswehere, leaning toward a patchy fog/low stratus
scenario with MVFR visibilities. We will continue to monitor and
make adjustments as needed. On Tuesday morning, any lingering low
stratus/fog is expected to break up/dissipate around mid-morning
with VFR conditions during the afternoon. Light winds overnight
and early Tuesday morning will become southeast at 4-7 kt on
Tuesday afternoon.
19
&&
.PREV DISCUSSION... /ISSUED 544 PM CST MON DEC 8 2014/
AVIATION...
/00Z TAFS/
Continuing along the lines of the previous TAF package, regarding
uncertainty with the extent of low stratus and fog development
tonight. The latest NAM12 and RUC13 indicate that fog and low
stratus may initially develop across our northeastern counties
early tonight, then develop (in a patchy nature) farther south and
west through the overnight hours. Could have IFR to LIFR
visibilities and ceilings at times, but with the uncertainty at
this time, going with a conservative approach with visibility
reductions, and by carrying scattered low cloud layers as opposed
to ceilings. Will monitor conditions throughout the evening and
tonight and will make adjustments as needed. Light winds will
continue tonight, and should eventually become southeast at 4-7 kt
on Tuesday afternoon.
PREV DISCUSSION... /ISSUED 325 PM CST Mon Dec 8 2014/
SHORT TERM...
(Tonight and Tuesday)
Skies have cleared across West Central Texas, allowing temperatures
to warm into the mid 60s to near 70 degrees this afternoon. Winds
remain light and variable across the region given the proximity to
the surface anticyclone. This surface high will remain in place
overnight but should shift far enough east to allow a return of weak
southerly winds.
With little change in the airmass and light winds in place across
the area, fog and low stratus is expected to develop again tonight.
This fog should remain patchy, and confidence is rather low
regarding what areas will actually see the most significant reduced
visibilities. Over the last two mornings, we have seen transient
dense fog develop in various locations, with visibilities down to
near zero at times. Fog is expected to lift in areas where low
clouds develop. Otherwise, expect low temperatures in the lower 40s,
possibly warming a few degrees if/when cloud cover develops. The
fly in the ointment is the anticipated increase in high clouds.
This could mitigate fog development.
Pleasant weather conditions are anticipated on Tuesday. High clouds
will continue to increase with southerly winds of 5 to 10 mph. No
precipitation is expected throughout the day with temperatures
warming into the mid and upper 60s.
Johnson
LONG TERM...
(Tuesday night through Monday)
As a weak upper ridge moves east of the area Tuesday night, a
weak upper short wave will move east over New Mexico giving the
forecast area our next chance of rainfall. The rainfall is
expected to be light and will expand eastward from the
southwestern CWA Tuesday night over the remaining CWA Wednesday
through Thursday. The chance of rainfall will end on Friday as
upper ridging builds over the area from the west in the wake of
the departing upper short wave. Highs on Wednesday will be in the
lower 60s warming into the Upper 60s to the lower 70s by Saturday.
Models are closing an upper low over southern New Mexico Saturday
night with the dryline tightening just west of the forecast area.
Forcing along the Pacific front/dryline Saturday night will bring
a chance of showers and thunderstorms over our western CWA
Saturday night, expanding through the remainder of the forecast
area through Sunday night. As the upper level system tracks east,
an associated cold front will move across the forecast area on
Sunday with cooler post-frontal highs on Monday ranging from the
upper 40s to the lower 50s.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 41 66 48 62 51 / 0 0 5 20 20
San Angelo 41 67 49 62 52 / 0 0 10 30 20
Junction 39 67 47 61 51 / 0 0 10 40 40
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1112 PM CST MON DEC 8 2014
.UPDATE...
AS EXPECTED...THE DENSE FOG HAS MOVED INTO THE FAR SOUTHEAST
ZONES...AS CONFIRMED BY A CALL TO ASPERMONT. THE FOG PROBABLY IS
NOT INTO COTTLE COUNTY JUST YET...BUT IT SHOULD EXPAND NORTH AND
WESTWARD INTO COTTLE COUNTY OVER THE NEXT FEW HOURS. GIVEN THIS
WE HAVE DECIDED TO ISSUE A DENSE FOG ADVISORY FOR COTTLE...KING
AND STONEWALL COUNTIES THROUGH 10 AM TUESDAY. NO OTHER CHANGES
HAVE BEEN MADE TO THE FORECAST ATTM.
&&
.PREV DISCUSSION... /ISSUED 935 PM CST MON DEC 8 2014/
UPDATE...
MINOR UPDATE TO ADJUST TEMPERATURES...DEWPOINT AND RH GRIDS
SLIGHTLY TO BETTER ACCOUNT FOR RECENT OBSERVATIONS AND TRENDS. WE
DID ALSO A MENTION OF DENSE FOG OVER THE EASTERN ROLLING PLAINS
BEFORE 06Z...WITH A MORE WIDESPREAD FOG MENTION THEREAFTER.
LATEST SATELLITE IMAGERY SHOWS AN EXPANDING AREA OF LOW CLOUDS AND
FOG EXTENDING FROM THE FAR EASTERN FRINGES OF THE SOUTHEASTERN CWA
INTO WESTERN NORTH TEXAS. KSPS HAS ALREADY REPORTED VISIBILITIES
DOWN TO 1/4 MILE IN FOG...AND WITH TEMPERATURES APPROACHING THE
DEWPOINT IN THE EASTERN ROLLING PLAINS...WE COULD SEE DENSE FOG
MATERIALIZE HERE TOO OVER THE NEXT FEW HOURS. ADDITIONALLY...THOUGH
PERHAPS LESS WIDESPREAD...FOG MAY BE POSSIBLE UP ON THE CAPROCK
LATER TONIGHT /WELL AFTER MIDNIGHT/. WE WILL CONTINUE TO MONITOR
THE PROGRESS OF THE FOG AND A DENSE FOG ADVISORY MAY BE NEEDED FOR
PARTS OF THE CWA LATER TONIGHT.
PREV DISCUSSION... /ISSUED 523 PM CST MON DEC 8 2014/
AVIATION...
THIN BUT RICH LOW LEVEL MOISTURE IN PLACE TO THE SOUTHEAST OF KLBB
AND SOUTH OF KCDS COULD BRING A PERIOD OF IFR CONDITIONS TO THE
TERMINALS TONIGHT. 18Z WRF-NAM NOT AS PESSIMISTIC AS ITS 12Z RUN
WHILE THE HRRR CONTINUES TO KEEP BEST POTENTIAL OFF THE CAPROCK AT
KCDS. ALSO SOME QUESTION OF HOW MUCH HIGH CLOUDS MIGHT AFFECT
COOLING AND THUS NARROWING OF TEMP-DEW SPREAD. WILL NOT MAKE MUCH
IN THE WAY OF CHANGE ATTM WITH EXPECTATION THAT RESTRICTIONS TO
VSBY AND/OR CIGS WILL BE NEAR OR AFTER 06Z. HOPEFULLY 00Z MODEL
RUNS AND LATER HI-RES RUNS WILL ADD CLARITY.
PREV DISCUSSION... /ISSUED 332 PM CST MON DEC 8 2014/
SHORT TERM...
RIDGING WILL PERSIST ACROSS OUR AREA OVER THE NEXT 24 HOURS WITH
VERY LITTLE...FROM A SYNOPTIC PERSPECTIVE...TO MAKE MUCH DIFFERENCE
IN SENSIBLE WEATHER. SOUTHERLY FLOW WILL PERSIST ALTHOUGH WE WILL
SEE A MORE SOUTHWESTERLY COMPONENTS ESPECIALLY WEST OF THE
ESCARPMENT. THAT SAID...SPEEDS SHOULD BE QUITE LIGHT AND POTENTIAL
FOR FOG WILL EXIST AREA WIDE. HOWEVER...THE MOST LIKELY LOCATION
FOR DENSE FOG WILL BE ACROSS THE ROLLING PLAINS. YET...GIVEN THE
INCREASING HIGH LEVEL CLOUDINESS APPARENT TO OUR WEST...EVEN THAT IS
NOT GUARANTEED. SO...WILL STICK WITH MENTION OF FOG /PATCHY WEST TO
AREAS EAST/ TONIGHT AND ALLOW THE OVERNIGHT SHIFTS TO ASSESS THE
POTENTIAL FOR LOW VISIBILITIES. TEMPERATURES SHOULD REMAIN WITHIN A
FEW DEGREES OF WHAT WE SAW DURING THE PREVIOUS 24 HOURS.
LONG TERM...
MENTIONABLE POPS HAVE BEEN REMOVED FOR WEDNESDAY THROUGH THURSDAY AS
CHANCES LOOK TO BE MORE UNLIKELY. WHILE THERE WILL BE AMPLE MOISTURE
AT THE LOW AND UPPER LEVELS...DRY AIR ASSOCIATED WITH SUBSIDENCE
BETWEEN 800 AND 600 MB WILL PREVENT WHAT LITTLE PRECIP THAT MAY
OCCUR FROM REACHING THE SURFACE. IN ADDITION TO DRY AIR...LIFT
ASSOCIATED WITH AN APPROACHING SHORTWAVE WILL BE WEAK AT BEST.
DESPITE A LACK OF PRECIP LOW LEVEL STRATUS WILL BE IN PLACE THROUGH
WEDNESDAY INTO LATE THURSDAY MORNING. ALONG WITH STRATUS FOG WILL
POSSIBLE ACROSS MUCH OF THE FA BOTH WEDNESDAY AND THURSDAY MORNING.
FOG HAS BEEN LEFT OUT OF THE GRIDS FOR FRIDAY MORNING AS WINDS ARE
EXPECTED TO TURN TO THE SOUTHWEST AS A LEE TROF APPROACHES THE AREA
WHICH SHOULD HELP KEEP SURFACE RH VALUES LOWER. STRATUS SHOULD ALSO
NOT BE AN ISSUE FRIDAY MORNING WITH MOSTLY DRY AIR WILL BE SITTING
OVER THE REGION.
BY FRIDAY AFTERNOON AN ELONGATED TROF WILL BE POSITIONED OVER THE
PACIFIC COAST WITH THE LEE TROF DIGGING FURTHER SOUTHWARD.
CONTINUOUS SURFACE WINDS OUT OF THE SOUTHWEST WILL HELP WARM TEMPS
TO NEAR 70 ON FRIDAY AND SATURDAY. THE UPPER LEVEL TROF SHOULD BE
NEAR THE FOOTHILLS OF THE ROCKIES BY LATE SATURDAY AND SHOULD BEGIN
TO ELONGATE FURTHER SOUTHWARD. THE GFS HAS BEEN FAIRLY CONSISTENT WITH
PINCHING OFF THE LOWER HALF OF THE TROF MAKING A CLOSED LOW WHICH
WOULD GIVE THE REGION A DECENT SHOT AT PRECIP. UNTIL THE MORE RECENT
12Z RUN THE ECMWF SHOWED A SIMILAR BUT SLOWER SOLUTION. THE 12Z
ECMWF KEEPS THE LOW CLOSED OFF ALONG THE US/CA BORDER WITH AN OPEN
TROF IN THE SOUTH-CENTRAL CONUS. THOUGH THE TROF REMAINS OPEN IT
MATCHES THE SPEED OF THE GFS ALMOST PERFECTLY. FOR NOW PRECIP
CHANCES HAVE BEEN KEPT IN THE FORECAST STARTING LATE SATURDAY WITH
HIGH POPS EXISTING OVER THE ROLLING PLAINS. THE BIGGER CHALLENGE
COMES WITH PRECIP TYPE LATE SUNDAY AFTER A COLD FRONT PUSHES INTO
THE REGION PENDING THAT THE LOW IS CLOSED. BOTH MODELS SHOW 850 MB
TEMPS REMAIN ABOVE FREEZING BUT NOT BY MUCH. THE 00Z RUN OF THE
ECMWF SHOWED 850 MB TEMPS DOWN TO -5C. SNOW WOULD NOT BE OUT OF
THE REALM OF POSSIBILITY IF TEMPS CAN COOL DOWN FAST ENOUGH...BUT
FOR NOW THE MENTION WILL BE FOR RAIN OR SNOW. REGARDLESS OF PRECIP
TEMPERATURES SHOULD BE NOTICEABLY COLDER BEHIND THE FRONT WITH
HIGHS AVERAGING IN THE MID 40S ON MONDAY WITH LOWS DIPPING BACK
DOWN BELOW FREEZING FOR MUCH OF THE AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 35 61 41 60 38 / 0 0 10 10 10
TULIA 35 61 42 59 42 / 0 0 10 10 10
PLAINVIEW 35 61 43 59 41 / 0 0 10 10 10
LEVELLAND 38 61 42 59 43 / 0 0 10 10 10
LUBBOCK 39 63 44 59 43 / 0 0 10 10 10
DENVER CITY 43 61 44 59 43 / 0 0 10 10 10
BROWNFIELD 40 61 44 59 45 / 0 0 10 10 10
CHILDRESS 39 66 43 62 47 / 0 0 10 10 10
SPUR 38 64 44 62 48 / 0 0 10 10 10
ASPERMONT 39 66 45 63 50 / 0 0 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST TUESDAY FOR THE FOLLOWING
ZONES: TXZ032-038-044.
&&
$$
07/23
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
145 PM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE COAST OF VIRGINIA WILL DEEPEN AS IT SHIFTS
UP TOWARD THE JERSEY COAST BY TUESDAY AFTERNOON. A TROUGH OF LOW
PRESSURE WILL MOVE THROUGH THE GREAT LAKES REGION AND MERGE WITH
THE COASTAL LOW BY TUESDAY NIGHT OVER NEW ENGLAND. ONCE THIS
HAPPENS OUR AREA WILL STAY IN A NORTHWEST FLOW THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1145 AM EST TUESDAY...
FORECAST AREA WILL BE IN BETWEEN THE UPPER TROUGH TO OUR WEST AND
THE SURFACE CYCLONE NEAR THE NEW JERSEY COAST. RIBBON OF DRYING IS
EVIDENT IN THE SATELLITE PIX WITH DRY AIR RESULTING IN SOME SUNNY
BREAKS RUNNING N-S THROUGH THE CENTER OF OUR CWA. CLOUDS FROM THE
UPPER TROUGH WERE ENTERING OUR WESTERN CWA...WHERE MOSTLY CLOUDY
SKIES WILL PREVAIL THROUGH THE AFTERNOON. MOSTLY CLOUDY CONDITIONS
WHERE ALSO FOUND ACROSS OUR EASTERN CWA WITH AN AREA OF RAIN STILL
PIVOTING THROUGH AREAS EAST OF HIGHWAY 29.
LATEST HRRR KEEPS DEFORMATION PRECIP ASSOCIATED WITH THE COASTAL
CYCLONE CONFINED TO OUR FAR EASTERN CWA FOR THE REMAINDER OF THE
AFTERNOON BEFORE PIVOTING SOUTHEAST AND AWAY FROM THE AREA. RAISED
POPS FOR PLACES LIKE SOUTH BOSTON TO ACCOUNT FOR THIS LINGERING
ACTIVITY. IN THE WESTERN CWA...DO NOT FORESEE MUCH ACTIVITY UNTIL
MUCH COLDER AIR FROM THE UPPER TROF ARRIVES LATER TONIGHT. UNTIL
THEN ANY PRECIP IN OUR UPSLOPE AREAS OF WRN GREENBRIER AND THE
HIGH COUNTRY OF NC WILL BE LIGHT.
8H TEMPS WILL START TO DROP FROM WEST TO EAST THIS AFTERNOON.
IN SPITE OF THE INCREASING CAA...SUNNY BREAKS JUST LEE OF THE
MOUNTAINS SHOULD ALLOW TEMPERATURES TO TEST 50 FROM MARTINSVILLE
TO GREENSBORO AND INCLUDING MOUNT AIRY AND WILKSBORO NC. WARMEST
READINGS WILL BE FOUND WITHIN THIS CORRIDOR THIS AFTERNOON.
ELSEWHERE...VARIED AMOUNTS OF CLOUDINESS WILL KEEP READINGS
LOWER.
FOR TONIGHT...COLDER AIR FROM THE PASSAGE OF THE UPPER TROUGH WILL
PENETRATE THE MOUNTAINS...850 TEMPS FALLING INTO THE M4-M8 DEG C
RANGE ACROSS THE WESTERN SLOPES. THIS WILL THEN FAVOR ACCUMULATING
UPSLOPE SNOW SHOWERS. ELSEWHERE...CLOUDS AND FLURRIES WILL LIKELY
BE FOUND AS FAR EAST AS THE BLUE RIDGE...DOWNSLOPE FLOW PROMOTING
LESS CLOUD COVER AND NO PRECIP FARTHER EAST.
AS FOR SNOWFALL AMOUNTS IN THE HIGH COUNTRY OF OUR WESTERN CWA...
MODELS INDICATE LIGHT AMOUNTS. SHALLOW DEPTH TO THE MOISTURE
PROFILES SUGGEST THE 1 TO 3 INCH RANGE. ATTM NO HEADLINES PLANNED
UNLESS NEW MODEL RUNS INDICATE MORE QPF.
ALSO FOR TONIGHT...WINDS INCREASE. BLUSTERY...BUT LESS THAN
ADVISORY THRESHOLDS.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM EST TUESDAY...
SURFACE LOW PRESSURE NEAR LONG ISLAND WEDNESDAY MORNING WILL MOVE
SLOWLY NORTH INTO THE INTERIOR OF NEW ENGLAND BY THURSDAY NIGHT.
NORTHWEST FLOW WILL CONTINUE FOR OUR AREA WITH A PROLONGED PERIOD OF
UPSLOPE RAIN/SNOW SHOWERS FOR THE PREFERRED AREAS OF SOUTHEAST WEST
VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA.
THERE WILL BE SOME DOWNWIND ISOLATED TO SCATTERED SHOWERS EAST TO
NEAR THE CREST OF THE BLUE RIDGE. AS TIME PROGRESSES THROUGH
THURSDAY...COVERAGE OF THE RAIN/SNOW SHOWERS WILL DECREASE AS
PROGRESSIVELY DRIER AIR WORKS ITS WAY INTO THE REGION. GUSTY
NORTHWEST WINDS MAY BE POSSIBLE ACROSS THE HIGHER TERRAIN
ESPECIALLY ABOVE 3K FEET WITH GUSTS BELOW WIND ADVISORY LEVELS.
SOME LIGHT ACCUMULATING SNOW IS POSSIBLE IN THE FAVORED UPSLOPE
LOCATIONS. SNOWFALL TOTALS DURING THIS PORTION OF THE FORECAST WILL
BE GREATEST ACROSS WESTERN GREENBRIER COUNTY WEST VIRGINIA WITH A 1
TO 3 INCH RANGE. THE REMAINDER OF THE PREFERRED UPSLOPE REGION OF
SOUTHEAST WEST VIRGINIA WILL MAINLY BE UNDER AN INCH. CAN NOT RULE
OUT AROUND ONE INCH FOR THE HIGHER TERRAIN OF WESTERN ASHE AND
WATAUGA COUNTIES IN NORTHWEST NORTH CAROLINA. LIGHTER TOTALS
EXPECTED ACROSS THE REST OF THE MOUNTAINS. HIGH PRESSURE WILL BUILD
EAST INTO OUR AREA BY THURSDAY NIGHT INTO FRIDAY MORNING.
TEMPERATURES DURING THE PERIOD WILL AVERAGE A FEW DEGREES BELOW
NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EST MONDAY...
MODELS ARE NOW IN THE SAME BALLPARK FOR THE EXTENDED...JUST NOT SURE
IF THE GAME IS FOOTBALL OR SOCCER. EVOLUTION TO A HIGHLY AMPLIFIED
UPPER PATTERN WITH DEVELOPMENT OF A CLOSED LOW DOING A SIT AND SPIN
OVER THE NORTHEAST US IS A FAVORED SOLUTION THROUGH THE END OF THE
WEEK. BEGIN TO SEE SIGNIFICANT DIFFERENCES AS WE HEAD INTO THE
WEEKEND WITH GFS BEING TYPICALLY MORE PROGRESSIVE AND EURO DIGGING
IN ITS HEELS. BY MONDAY UPPER RIDGE AXIS SHOULD BE CROSSING THE
REGION AS NEXT SOUTHERN STREAM CLOSED LOW APPROACHES FROM THE LOWER
MISSISSIPPI VALLEY.
EVEN WITH THE MODEL DIFFERENCES...IMPACTS ON SENSIBLE WEATHER
ELEMENTS THROUGH THE EXTENDED WILL BE SMALL. NW FLOW UPSLOPE SNOW
SHOWERS ACROSS THE FAR WRN SLOPES OF THE BLUE RIDGE WILL BE WINDING
DOWN THURSDAY NIGHT AS SFC HIGH SLIDES IN FROM THE WEST. MAYBE SOME
FLURRIES FAR WRN SLOPES THROUGH THE END OF THE WEEK...BUT LOOKING
LIKE QUIET WEATHER ELSEWHERE. WE THEN GET INTO SOME WEAK LIFT AS A
LIGHT WARM AIR ADVECTION PATTERN SETS UP SATURDAY NIGHT THROUGH
SUNDAY. THIS MAY BE ENOUGH TO GET SOME SPRINKLES GOING BUT NOTHING
TOO EXCITING...AND GIVEN THE MODEL UNCERTAINTY THIS FAR OUT WILL GO
WITH POPS NO HIGHER THAN SLIGHT CHC CONFINED TO WEST OF THE BLUE
RIDGE. EXPECT A WARMING TREND FROM BELOW NORMAL FRIDAY TO ABOVE
NORMAL BY THE START OF NEXT WEEK.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AS OF 130 PM EST TUESDAY...
THE HRRR/NAM MAINTAINS AN AREA OF LOW LEVEL MOISTURE AND LOW CIGS
JUST EAST OF KLYH-KDAN LINE THROUGH THIS EVENING BEFORE MOVING IT
EAST AND OFF THE COAST LATE TONIGHT. ASIDE FROM THIS AREA OF
MOISTURE ASSOCIATED WITH THE COASTAL CYCLONE...FOCUS FOR THE RNK
CWA WILL TURN TOWARD THE WEST WHERE CONSIDERABLE MOISTURE WAS
BECOMING BANKED UP AGAINST THE WEST SIDE OF THE APPALACHIAN
MOUNTAINS. MODELS INDICATE THIS MOISTURE WILL REMAIN IN PLACE
THROUGH AT LEAST WEDNESDAY NIGHT.
THAT SAID...MVFR TO PREVAIL ACROSS THE MOUNTAINS THE NEXT 24-48
HOURS PER MOIST NORTHWEST FLOW RESULTING IN 1-3KFT CIGS. VSBYS
TONIGHT THROUGH WEDNESDAY WILL BECOME RESTRICTED ATTMS PER
DEVELOPMENT OF SNOW SHOWERS AND FLURRIES...ESP THE WESTERN SLOPES
VCNTY OF TNB-BLF AND JUST WEST OF LWB. EAST OF THE HIGHER
MOUNTAINS...NORTHWEST WINDS WILL RESULT IN GRADUAL CLEARING WITH
RETURN OF VFR.
WINDS SHOULD ALSO PICK UP QUITE A BIT FOR TONIGHT AND
WEDNESDAY...BLUSTERY ATTMS. GUSTS OF 18-25KTS WILL BE COMMON
WEDNESDAY.
EXTENDED DISCUSSION...
SNOW SHOWERS AND MVFR UPSLOPE CLOUDS WILL CONTINUE IN SOUTHEAST
WEST VIRGINIA THROUGH THURSDAY MORNING. VFR CONDITIONS ARE
EXPECTED IN THE EAST. GUSTY WINDS ARE LIKELY THROUGH WEDNESDAY
NIGHT.
THURSDAY NIGHT THROUGH SATURDAY...ASIDE FOR SOME LINGERING MVFR
CLOUDINESS IN THE WV MOUNTAINS THURSDAY...HIGH PRESSURE WILL BUILD
OVER THE MID ATLANTIC THURSDAY THROUGH SATURDAY WITH VFR AND
DIMINISHING WINDS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...PM
SHORT TERM...KK
LONG TERM...MBS
AVIATION...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1204 PM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE COAST OF VIRGINIA WILL DEEPEN AS IT SHIFTS
UP TOWARD THE JERSEY COAST BY TUESDAY AFTERNOON. A TROUGH OF LOW
PRESSURE WILL MOVE THROUGH THE GREAT LAKES REGION AND MERGE WITH
THE COASTAL LOW BY TUESDAY NIGHT OVER NEW ENGLAND. ONCE THIS
HAPPENS OUR AREA WILL STAY IN A NORTHWEST FLOW THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1145 AM EST TUESDAY...
FORECAST AREA WILL BE IN BETWEEN THE UPPER TROUGH TO OUR WEST AND
THE SURFACE CYCLONE NEAR THE NEW JERSEY COAST. RIBBON OF DRYING IS
EVIDENT IN THE SATELLITE PIX WITH DRY AIR RESULTING IN SOME SUNNY
BREAKS RUNNING N-S THROUGH THE CENTER OF OUR CWA. CLOUDS FROM THE
UPPER TROUGH WERE ENTERING OUR WESTERN CWA...WHERE MOSTLY CLOUDY
SKIES WILL PREVAIL THROUGH THE AFTERNOON. MOSTLY CLOUDY CONDITIONS
WHERE ALSO FOUND ACROSS OUR EASTERN CWA WITH AN AREA OF RAIN STILL
PIVOTING THROUGH AREAS EAST OF HIGHWAY 29.
LATEST HRRR KEEPS DEFORMATION PRECIP ASSOCIATED WITH THE COASTAL
CYCLONE CONFINED TO OUR FAR EASTERN CWA FOR THE REMAINDER OF THE
AFTERNOON BEFORE PIVOTING SOUTHEAST AND AWAY FROM THE AREA. RAISED
POPS FOR PLACES LIKE SOUTH BOSTON TO ACCOUNT FOR THIS LINGERING
ACTIVITY. IN THE WESTERN CWA...DO NOT FORESEE MUCH ACTIVITY UNTIL
MUCH COLDER AIR FROM THE UPPER TROF ARRIVES LATER TONIGHT. UNTIL
THEN ANY PRECIP IN OUR UPSLOPE AREAS OF WRN GREENBRIER AND THE
HIGH COUNTRY OF NC WILL BE LIGHT.
8H TEMPS WILL START TO DROP FROM WEST TO EAST THIS AFTERNOON.
IN SPITE OF THE INCREASING CAA...SUNNY BREAKS JUST LEE OF THE
MOUNTAINS SHOULD ALLOW TEMPERATURES TO TEST 50 FROM MARTINSVILLE
TO GREENSBORO AND INCLUDING MOUNT AIRY AND WILKSBORO NC. WARMEST
READINGS WILL BE FOUND WITHIN THIS CORRIDOR THIS AFTERNOON.
ELSEWHERE...VARIED AMOUNTS OF CLOUDINESS WILL KEEP READINGS
LOWER.
FOR TONIGHT...COLDER AIR FROM THE PASSAGE OF THE UPPER TROUGH WILL
PENETRATE THE MOUNTAINS...850 TEMPS FALLING INTO THE M4-M8 DEG C
RANGE ACROSS THE WESTERN SLOPES. THIS WILL THEN FAVOR ACCUMULATING
UPSLOPE SNOW SHOWERS. ELSEWHERE...CLOUDS AND FLURRIES WILL LIKELY
BE FOUND AS FAR EAST AS THE BLUE RIDGE...DOWNSLOPE FLOW PROMOTING
LESS CLOUD COVER AND NO PRECIP FARTHER EAST.
AS FOR SNOWFALL AMOUNTS IN THE HIGH COUNTRY OF OUR WESTERN CWA...
MODELS INDICATE LIGHT AMOUNTS. SHALLOW DEPTH TO THE MOISTURE
PROFILES SUGGEST THE 1 TO 3 INCH RANGE. ATTM NO HEADLINES PLANNED
UNLESS NEW MODEL RUNS INDICATE MORE QPF.
ALSO FOR TONIGHT...WINDS INCREASE. BLUSTERY...BUT LESS THAN
ADVISORY THRESHOLDS.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM EST TUESDAY...
SURFACE LOW PRESSURE NEAR LONG ISLAND WEDNESDAY MORNING WILL MOVE
SLOWLY NORTH INTO THE INTERIOR OF NEW ENGLAND BY THURSDAY NIGHT.
NORTHWEST FLOW WILL CONTINUE FOR OUR AREA WITH A PROLONGED PERIOD OF
UPSLOPE RAIN/SNOW SHOWERS FOR THE PREFERRED AREAS OF SOUTHEAST WEST
VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA.
THERE WILL BE SOME DOWNWIND ISOLATED TO SCATTERED SHOWERS EAST TO
NEAR THE CREST OF THE BLUE RIDGE. AS TIME PROGRESSES THROUGH
THURSDAY...COVERAGE OF THE RAIN/SNOW SHOWERS WILL DECREASE AS
PROGRESSIVELY DRIER AIR WORKS ITS WAY INTO THE REGION. GUSTY
NORTHWEST WINDS MAY BE POSSIBLE ACROSS THE HIGHER TERRAIN
ESPECIALLY ABOVE 3K FEET WITH GUSTS BELOW WIND ADVISORY LEVELS.
SOME LIGHT ACCUMULATING SNOW IS POSSIBLE IN THE FAVORED UPSLOPE
LOCATIONS. SNOWFALL TOTALS DURING THIS PORTION OF THE FORECAST WILL
BE GREATEST ACROSS WESTERN GREENBRIER COUNTY WEST VIRGINIA WITH A 1
TO 3 INCH RANGE. THE REMAINDER OF THE PREFERRED UPSLOPE REGION OF
SOUTHEAST WEST VIRGINIA WILL MAINLY BE UNDER AN INCH. CAN NOT RULE
OUT AROUND ONE INCH FOR THE HIGHER TERRAIN OF WESTERN ASHE AND
WATAUGA COUNTIES IN NORTHWEST NORTH CAROLINA. LIGHTER TOTALS
EXPECTED ACROSS THE REST OF THE MOUNTAINS. HIGH PRESSURE WILL BUILD
EAST INTO OUR AREA BY THURSDAY NIGHT INTO FRIDAY MORNING.
TEMPERATURES DURING THE PERIOD WILL AVERAGE A FEW DEGREES BELOW
NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EST MONDAY...
MODELS ARE NOW IN THE SAME BALLPARK FOR THE EXTENDED...JUST NOT SURE
IF THE GAME IS FOOTBALL OR SOCCER. EVOLUTION TO A HIGHLY AMPLIFIED
UPPER PATTERN WITH DEVELOPMENT OF A CLOSED LOW DOING A SIT AND SPIN
OVER THE NORTHEAST US IS A FAVORED SOLUTION THROUGH THE END OF THE
WEEK. BEGIN TO SEE SIGNIFICANT DIFFERENCES AS WE HEAD INTO THE
WEEKEND WITH GFS BEING TYPICALLY MORE PROGRESSIVE AND EURO DIGGING
IN ITS HEELS. BY MONDAY UPPER RIDGE AXIS SHOULD BE CROSSING THE
REGION AS NEXT SOUTHERN STREAM CLOSED LOW APPROACHES FROM THE LOWER
MISSISSIPPI VALLEY.
EVEN WITH THE MODEL DIFFERENCES...IMPACTS ON SENSIBLE WEATHER
ELEMENTS THROUGH THE EXTENDED WILL BE SMALL. NW FLOW UPSLOPE SNOW
SHOWERS ACROSS THE FAR WRN SLOPES OF THE BLUE RIDGE WILL BE WINDING
DOWN THURSDAY NIGHT AS SFC HIGH SLIDES IN FROM THE WEST. MAYBE SOME
FLURRIES FAR WRN SLOPES THROUGH THE END OF THE WEEK...BUT LOOKING
LIKE QUIET WEATHER ELSEWHERE. WE THEN GET INTO SOME WEAK LIFT AS A
LIGHT WARM AIR ADVECTION PATTERN SETS UP SATURDAY NIGHT THROUGH
SUNDAY. THIS MAY BE ENOUGH TO GET SOME SPRINKLES GOING BUT NOTHING
TOO EXCITING...AND GIVEN THE MODEL UNCERTAINTY THIS FAR OUT WILL GO
WITH POPS NO HIGHER THAN SLIGHT CHC CONFINED TO WEST OF THE BLUE
RIDGE. EXPECT A WARMING TREND FROM BELOW NORMAL FRIDAY TO ABOVE
NORMAL BY THE START OF NEXT WEEK.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
AS OF 650 AM EST TUESDAY...
FOLLOWED A BLEND OF THE SREF AND NAM THIS MORNING WITH TRENDS
TOWARD VFR BY LATE MORNING FROM ROA EAST...THOUGH DAN MAY TAKE
UNTIL 18Z TO GO VFR. MEANWHILE...NW FLOW AND UPPER LOW WILL BE
KEEPING CIGS MVFR OR WORSE OVER THE MTNS. HAVE POCKETS OF DENSE
FOG AT BLF...WITH MVFR FOG AT LWB/BCB. THINK THE FOG WILL CLEAR
OUT SOON...LEAVING BEHIND AN MVFR CIG...AT BLF/LWB...WITH BCB
GOING TO VFR FOR A FEW HOURS THIS AFTERNOON.
AS THE UPPER LOW MOVES ACROSS TO OUR SOUTH AND EAST THIS AFTERNOON
LOOK FOR RAIN AND SNOW SHOWERS TO INCREASE FOR SE WV INTO THE NC
MTNS. WILL HAVE BLF STAYING MVFR THROUGH THE PERIOD CHANGING TO
ALL SNOW BY 02Z TONIGHT. COULD SEE SOME CIGS DROP BELOW 1KFT.
LWB IS GOING TO ALSO BE MVFR...THOUGH A SMALL WINDOW OF VFR CIGS
MAY OCCUR THIS AFTERNOON BEFORE THE NW FLOW GETS GOING.
BCB MAY SEE A FEW FLURRIES TONIGHT WHILE CIGS DROP BACK TO JUST
UNDER 3KFT.
WINDS SHOULD ALSO PICK UP LATER TODAY AND ESPECIALLY LATE TONIGHT
AS THE LOW OFF THE MID ATLANTIC COAST DEEPENS. SOME GUSTS OVER 20
KTS POSSIBLE BY WED MORNING.
EXTENDED DISCUSSION...
SNOW SHOWERS AND MVFR UPSLOPE CLOUDS WILL CONTINUE IN SOUTHEAST
WEST VIRGINIA THROUGH THURSDAY MORNING. VFR CONDITIONS ARE
EXPECTED IN THE EAST. GUSTY WINDS ARE LIKELY THROUGH WEDNESDAY
NIGHT.
THURSDAY NIGHT THROUGH SATURDAY...ASIDE FOR SOME LINGERING MVFR
CLOUDINESS IN THE WV MOUNTAINS THURSDAY...HIGH PRESSURE WILL BUILD
OVER THE MID ATLANTIC THURSDAY THROUGH SATURDAY WITH VFR AND
DIMINISHING WINDS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...PM
SHORT TERM...KK
LONG TERM...MBS
AVIATION...AMS/PM/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
731 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE COAST OF VIRGINIA WILL DEEPEN AS IT SHIFTS
UP TOWARD THE JERSEY COAST BY TUESDAY AFTERNOON. A TROUGH OF LOW
PRESSURE WILL MOVE THROUGH THE GREAT LAKES REGION AND MERGE WITH
THE COASTAL LOW BY TUESDAY NIGHT OVER NEW ENGLAND. ONCE THIS
HAPPENS OUR AREA WILL STAY IN A NORTHWEST FLOW THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 720 AM EST TUESDAY...
WILL BE LETTING THE REST OF THE WINTER WX ADVISORY EXPIRE AT 8 AM.
NO PRECIP TO SPEAK OF IN THE COLDER AREAS THIS MORNING...BUT THERE
REMAINS PATCHY DZ/FZDZ OR FOG. THINK AS THE NW/N FLOW INCREASES
WILL SEE THE SRN SHENANDOAH VALLEY/HIGHLANDS SCOUR OUT...BUT
MODELS DO CONTINUE TO HINT AT A NARROW BAND OF PRECIP ROTATING
BACK ACROSS THE FOOTHILLS AND PIEDMONT OF VA...ALONG AND NORTH OF
AN AMHERST TO HALIFAX LINE BY LATE MORNING...BUT APPEARS TEMPS
WILL BE ABOVE FREEZING THEN...SO NO WINTER PTYPE CONCERNS.
FURTHER WEST...SLOWER TIMING OVERALL WITH UPPER LOW MOVING ACROSS
KY...AND PRECIP ARRIVING IN THE MTNS. LOOKS LIKE THE LATEST RAP IS
NOT THAT FAR OFF AND WILL START TO SEE PRECIP MAINLY RAIN...SOME
SNOW SHOWERS MOVING INTO THE MTNS OF NC/FAR SW VA AND SE WV BEFORE
NOON.
NOT TOO MUCH ELSE CHANGED IN THE FORECAST THRU THE DAY.
PREVIOUS DISCUSSION AT 330 AM TODAY...
UPPER LOW CLOSING OFF ACROSS THE OHIO VALLEY THIS MORNING WILL TRACK
INTO THE SOUTHEAST MOUNTAINS OF KY BY MIDDAY TURNING THE UPPER FLOW
MORE SOUTHERLY...AND ENHANCING THE SFC LOW MOVING NWD TOWARD THE
DELMARVA. FOR US...THIS UPPER LOW WILL BRING SOME DRYING BEFORE WE
GET THE SFC WINDS TURNED AROUND MORE TOWARD THE NW WITH LOW LVL
MOISTURE BANKED UP ACROSS THE WRN CWA. AT THE SAME TIME...THE MODELS
ARE ENHANCING A BACK EDGE BAND OF PRECIP TOWARD OUR NERN CWA THIS
AFTERNOON ROUGHLY FROM AMHERST COUNTY SOUTHEAST TO CHARLOTTE COUNTY.
MADE ADJUSTMENTS TO THE FORECAST TO HANG ONTO CHANCE POPS THROUGH
THE DAY.
THIS MORNING THE WINTRY PRECIP HAS ALL BUT ENDED AS TEMPS REMAIN
STUCK IN THE LOWER TO MID 30S. COLDEST TEMPS LIE WEST OF THE BLUE
RIDGE...AND MORE AWAY FROM WHERE ANY SUBSTANTIAL PRECIP IS FALLING.
THERE WILL BE SOME PATCHY SLEET/SNOW OVER THE SRN SHENANDOAH VLY
THIS MORNING INTO THE ALLEGHANYS AND BLUE RIDGE NORTH OF
ROANOKE...SO WILL MAINTAIN THE ADVISORY HERE...WHILE VIRGINIA DOT
CONTINUES TO SHOW MINOR ACCUMULATION ON ROADS GENERALLY FROM
COVINGTON TO LEXINGTON AND NORTH. WILL CANCEL THE ADVISORY FROM NEW
CASTLE TO ROANOKE TO ROCKY MOUNT SOUTH. POTENTIAL FOR CANCELLING
FURTHER NORTH EARLY IF ALL PRECIP EXITS SOONER.
PERUSING THE ROAD TEMPS VIA DOT...MOST IN OUR CWA ARE JUST ABOVE
FREEZING...OF COURSE THIS DOES NOT COVER THE SECONDARY HIGHWAYS...SO
SOME BRIDGES AND OVERPASSES COULD HAVE A FEW SLICK SPOTS.
IN ADDITION...THERE IS SOME THICK FOG ALONG THE MOUNTAINS...AND SOME
RIME ICING COULD OCCUR AND ALSO LEAD TO PATCHY SLICK SPOTS AT
ELEVATIONS ABOVE 2500 FT WEST ALONG AND WEST OF THE BLUE RIDGE.
8H TEMPS WILL START TO DROP FROM WEST TO EAST BY THIS AFTERNOON.
THIS MORNING THE 0C ISOTHERM LIES OVER SE WV SOUTH INTO FAR SW VA.
BY MIDDAY IT SHOULD BE TO THE BLUE RIDGE...THEN EAST OF THE CWA
EARLY THIS EVENING AS THE UPPER LOW SLIDES ACROSS THE CAROLINAS.
THIS PATH DRIVES THE COLDER AIR FIRST INTO THE NC MTNS THEN
NORTH...AND SEEMS TO FAVOR HIGHER POPS FOR THE NC MTNS FIRST AS
WELL...THEN AS THE LOW MOVES NE OVER THE MID ATLANTIC TONIGHT THE
NEXT VORT SHIFTS ACROSS THE WV MTNS...AND CONTINUES THE SNOW
SHOWERS HERE.
MODELS INDICATE LIGHT AMOUNTS AS THE TRAJECTORIES DO NOT FAVOR
MAXIMUM UPSLOPE ENHANCEMENT...BUT STILL A 1 TO 3 INCH RANGE IS
EXPECTED...WITH THE HIGHER END...3 INCHES OVER THE NW SECTIONS OF
GREENBRIER COUNTY. AT THIS TIME...THERE WILL BE NO HEADLINES
ADDED...FOR THE UPSLOPE THOUGH COULD SEE WRN GREENBRIER GET ADDED
LATER TODAY IF MODEL SOLUTIONS FAVOR MORE QPF.
FOR HIGHS TODAY WENT CLOSE TO WHAT WE HAD PREVIOUSLY. TEMPS WILL BE
STEADY OR COULD SLOWLY RISE IN THE WEST BEFORE THE STRONG CAA
ARRIVES WITH THE UPPER LOW...BUT STILL KEEPING THE MOUNTAINS IN THE
30S...WITH AROUND 40 ACROSS THE NRV...AND MID TO UPPER 40S
EAST...ESPECIALLY IF CLEARING TAKES SHAPE. THINK THE SRN CWA EAST OF
THE BLUE RIDGE IN NC THRU SOUTHSIDE VA COULD SEE SOME SUN AT TIME
THIS AFTERNOON.
TONIGHT...WINDS PICK UP LATE AND WITH CLOUDS IN THE WEST AND 8H
TEMPS AROUND -6C...SHOULD SEE LOWS IN THE MID TO UPPER 20S...WHILE
WINDS ALSO KEEP THE EASTERN CWA MIXED ENOUGH TO BRING THEM DOWN INTO
THE LOWER TO MID 30S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM EST TUESDAY...
SURFACE LOW PRESSURE NEAR LONG ISLAND WEDNESDAY MORNING WILL MOVE
SLOWLY NORTH INTO THE INTERIOR OF NEW ENGLAND BY THURSDAY NIGHT.
NORTHWEST FLOW WILL CONTINUE FOR OUR AREA WITH A PROLONGED PERIOD OF
UPSLOPE RAIN/SNOW SHOWERS FOR THE PREFERRED AREAS OF SOUTHEAST WEST
VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA.
THERE WILL BE SOME DOWNWIND ISOLATED TO SCATTERED SHOWERS EAST TO
NEAR THE CREST OF THE BLUE RIDGE. AS TIME PROGRESSES THROUGH
THURSDAY...COVERAGE OF THE RAIN/SNOW SHOWERS WILL DECREASE AS
PROGRESSIVELY DRIER AIR WORKS ITS WAY INTO THE REGION. GUSTY
NORTHWEST WINDS MAY BE POSSIBLE ACROSS THE HIGHER TERRAIN
ESPECIALLY ABOVE 3K FEET WITH GUSTS BELOW WIND ADVISORY LEVELS.
SOME LIGHT ACCUMULATING SNOW IS POSSIBLE IN THE FAVORED UPSLOPE
LOCATIONS. SNOWFALL TOTALS DURING THIS PORTION OF THE FORECAST WILL
BE GREATEST ACROSS WESTERN GREENBRIER COUNTY WEST VIRGINIA WITH A 1
TO 3 INCH RANGE. THE REMAINDER OF THE PREFERRED UPSLOPE REGION OF
SOUTHEAST WEST VIRGINIA WILL MAINLY BE UNDER AN INCH. CAN NOT RULE
OUT AROUND ONE INCH FOR THE HIGHER TERRAIN OF WESTERN ASHE AND
WATAUGA COUNTIES IN NORTHWEST NORTH CAROLINA. LIGHTER TOTALS
EXPECTED ACROSS THE REST OF THE MOUNTAINS. HIGH PRESSURE WILL BUILD
EAST INTO OUR AREA BY THURSDAY NIGHT INTO FRIDAY MORNING.
TEMPERATURES DURING THE PERIOD WILL AVERAGE A FEW DEGREES BELOW
NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EST MONDAY...
MODELS ARE NOW IN THE SAME BALLPARK FOR THE EXTENDED...JUST NOT SURE
IF THE GAME IS FOOTBALL OR SOCCER. EVOLUTION TO A HIGHLY AMPLIFIED
UPPER PATTERN WITH DEVELOPMENT OF A CLOSED LOW DOING A SIT AND SPIN
OVER THE NORTHEAST US IS A FAVORED SOLUTION THROUGH THE END OF THE
WEEK. BEGIN TO SEE SIGNIFICANT DIFFERENCES AS WE HEAD INTO THE
WEEKEND WITH GFS BEING TYPICALLY MORE PROGRESSIVE AND EURO DIGGING
IN ITS HEELS. BY MONDAY UPPER RIDGE AXIS SHOULD BE CROSSING THE
REGION AS NEXT SOUTHERN STREAM CLOSED LOW APPROACHES FROM THE LOWER
MISSISSIPPI VALLEY.
EVEN WITH THE MODEL DIFFERENCES...IMPACTS ON SENSIBLE WEATHER
ELEMENTS THROUGH THE EXTENDED WILL BE SMALL. NW FLOW UPSLOPE SNOW
SHOWERS ACROSS THE FAR WRN SLOPES OF THE BLUE RIDGE WILL BE WINDING
DOWN THURSDAY NIGHT AS SFC HIGH SLIDES IN FROM THE WEST. MAYBE SOME
FLURRIES FAR WRN SLOPES THROUGH THE END OF THE WEEK...BUT LOOKING
LIKE QUIET WEATHER ELSEWHERE. WE THEN GET INTO SOME WEAK LIFT AS A
LIGHT WARM AIR ADVECTION PATTERN SETS UP SATURDAY NIGHT THROUGH
SUNDAY. THIS MAY BE ENOUGH TO GET SOME SPRINKLES GOING BUT NOTHING
TOO EXCITING...AND GIVEN THE MODEL UNCERTAINTY THIS FAR OUT WILL GO
WITH POPS NO HIGHER THAN SLIGHT CHC CONFINED TO WEST OF THE BLUE
RIDGE. EXPECT A WARMING TREND FROM BELOW NORMAL FRIDAY TO ABOVE
NORMAL BY THE START OF NEXT WEEK.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
AS OF 650 AM EST TUESDAY...
FOLLOWED A BLEND OF THE SREF AND NAM THIS MORNING WITH TRENDS
TOWARD VFR BY LATE MORNING FROM ROA EAST...THOUGH DAN MAY TAKE
UNTIL 18Z TO GO VFR. MEANWHILE...NW FLOW AND UPPER LOW WILL BE
KEEPING CIGS MVFR OR WORSE OVER THE MTNS. HAVE POCKETS OF DENSE
FOG AT BLF...WITH MVFR FOG AT LWB/BCB. THINK THE FOG WILL CLEAR
OUT SOON...LEAVING BEHIND AN MVFR CIG...AT BLF/LWB...WITH BCB
GOING TO VFR FOR A FEW HOURS THIS AFTERNOON.
AS THE UPPER LOW MOVES ACROSS TO OUR SOUTH AND EAST THIS AFTERNOON
LOOK FOR RAIN AND SNOW SHOWERS TO INCREASE FOR SE WV INTO THE NC
MTNS. WILL HAVE BLF STAYING MVFR THROUGH THE PERIOD CHANGING TO
ALL SNOW BY 02Z TONIGHT. COULD SEE SOME CIGS DROP BELOW 1KFT.
LWB IS GOING TO ALSO BE MVFR...THOUGH A SMALL WINDOW OF VFR CIGS
MAY OCCUR THIS AFTERNOON BEFORE THE NW FLOW GETS GOING.
BCB MAY SEE A FEW FLURRIES TONIGHT WHILE CIGS DROP BACK TO JUST
UNDER 3KFT.
WINDS SHOULD ALSO PICK UP LATER TODAY AND ESPECIALLY LATE TONIGHT
AS THE LOW OFF THE MID ATLANTIC COAST DEEPENS. SOME GUSTS OVER 20
KTS POSSIBLE BY WED MORNING.
EXTENDED DISCUSSION...
SNOW SHOWERS AND MVFR UPSLOPE CLOUDS WILL CONTINUE IN SOUTHEAST
WEST VIRGINIA THROUGH THURSDAY MORNING. VFR CONDITIONS ARE
EXPECTED IN THE EAST. GUSTY WINDS ARE LIKELY THROUGH WEDNESDAY
NIGHT.
THURSDAY NIGHT THROUGH SATURDAY...ASIDE FOR SOME LINGERING MVFR
CLOUDINESS IN THE WV MOUNTAINS THURSDAY...HIGH PRESSURE WILL BUILD
OVER THE MID ATLANTIC THURSDAY THROUGH SATURDAY WITH VFR AND
DIMINISHING WINDS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR VAZ019-
020-023-024-034-035.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WP
SHORT TERM...KK
LONG TERM...MBS
AVIATION...AMS/PM/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
127 AM EST TUE DEC 9 2014
.SYNOPSIS...
LOW PRESSURE OFF THE COAST OF VIRGINIA WILL DEEPEN AS IT SHIFTS
UP TOWARD THE JERSEY COAST BY TUESDAY AFTERNOON. A TROUGH OF LOW
PRESSURE WILL MOVE THROUGH THE GREAT LAKES REGION AND MERGE WITH
THE COASTAL LOW BY TUESDAY NIGHT OVER NEW ENGLAND. ONCE THIS
HAPPENS OUR AREA WILL STAY IN A NORTHWEST FLOW THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 110 AM EST TUESDAY...
RADAR SHOWING EDGE OF SOLID PRECIP ALONG/EAST OF THE BLUE RIDGE
FROM PATRICK COUNTY VA NORTH INTO THE SOUTHERN SHENANDOAH
VALLEY...WITH JUST SCATTERED POCKETS OF PRECIP WEST. WITH THE SW
CWA CLEARING OF PRECIP CANCELLED THE WINTER WX ADVISORY FROM
PULASKI AND WYTHE SOUTH TO CARROLL AND GRAYSON. SOME PATCHY
DRIZZLE/FREEZING DRIZZLE STILL POSSIBLE FOR ANOTHER FEW HOURS BUT
OVERALL THREAT OF ICY ROADS IS TOO LOW TO HAVE AN ADVISORY.
REST OF THE ADVISORY AREA WILL REMAIN IN EFFECT TIL 8 AM...THOUGH
IF THINGS CLEAR OUT SOONER...A FEW MORE COUNTIES COULD BE CLEARED
BY 4 AM.
TEMPS ARE RUNNING GENERALLY JUST BELOW FREEZING ALONG AND WEST OF
THE BLUE RIDGE TO THE UPPER 30S OUT EAST.
THE 00Z NAM AND THE LATEST RAP WERE SHOWING MOST OF THE QPF
STAYING TOWARD LYH AND NORTHEAST AS WE HEAD THROUGH THE MORNING.
WHERE THE ADVISORY IS IN PLACE...ONLY LIGHT AMOUNTS ARE EXPECTED.
PREVIOUS VALID DISCUSSION....
NEXT ROUND OF PRECIP IN THE WEST WILL HOLD OFF TIL AROUND OR AFTER
DAYBREAK WHEN THE UPPER TROUGH PASSES AND THE UPSLOPE SNOW
SHOWERS BEGIN.
FOR TUESDAY...THE FLOW TURNS QUICKLY NORTHWEST BEHIND DEEPENING
SURFACE CYCLONE AND INCREASING COLD ADVECTION...WITH SHOWERY
PRECIPITATION IN FAVORED UPSLOPE AREAS OF OUR WESTERN CWA...
ESPECIALLY LATE IN DAY.
TEMPERATURES WILL STRUGGLE TO WARM TUESDAY PER INCREASING COLD AIR
ADVECTION...BUT THINK WE MANAGE THE 40S MOST AREAS...WITH THE
EXCEPTION OF THE MOUNTAINS WHERE CLOUDS AND DEVELOPING SHOWERY
PRECIPITATION WILL PUT A DRAG ON THE THERMOMETER. BY THE END OF
THE DAY...AN INCH OR TWO OF SNOW IS POSSIBLE IN NORTHWEST
GREENBRIER COUNTY...AND ALONG THE WESTERN SLOPES INTO THE HIGH
COUNTRY OF NC. ELSEWHERE...MAYBE SOME FLURRIES OR SPRINKLES BUT
THATS ABOUT IT. BIGGEST DEVELOPMENT WILL BE THE INCREASE IN
NORTHWESTERLY WINDS WHICH WILL BECOME BLUSTERY AS WE PROGRESS
INTO TUESDAY NIGHT.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
AS OF 400 PM EST MONDAY...
THE STRENGTHENING UPPER LOW IS PROGGED TO CROSS THE REGION TUESDAY
EVENING. THIS WILL QUICKLY BRING AN END TO ANY WARM NOSE CONCERNS IN
THE LOWER THERMAL PROFILE AS A COLD FRONT CROSSES THE REGION. BEHIND
THE FRONT NORTHWEST WINDS WILL BECOME GUSTY AS THE PRESSURE GRADIENT
TIGHTENS IN ASSOCIATION WITH THE DEVELOPING NOREASTER. THIS WILL
BRING A PROLONGED PERIOD OF UPSLOPE RAIN/SNOW SHOWERS TO THE
PREFERRED AREAS OF SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN
MOUNTAINS OF NORTH CAROLINA. THERE WILL BE SOME DOWNWIND ISOLATED TO
SCATTERED ACTIVITY EAST TO NEAR THE CREST OF THE BLUE RIDGE. AS TIME
PROGRESSES THROUGH THURSDAY...COVERAGE OF THE RAIN/SNOW SHOWERS WILL
DECREASE AS PROGRESSIVELY DRIER AIR WORKS ITS WAY INTO THE REGION.
SOME OF THE HIGHER WIND GUSTS WILL BE AT ELEVATIONS ABOVE 3000 FT
MSL AND REACH THE 30 TO 40 MPH RANGE.
SNOWFALL TOTALS DURING THIS PORTION OF THE FORECAST WILL BE GREATEST
ACROSS WESTERN GREENBRIER COUNTY WV WITH A 1 TO 4 INCH RANGE. THE
REMAINDER OF THE PREFERRED UPSLOPE REGION OF SOUTHEAST WEST VIRGINIA
WILL MAINLY BE UNDER AN INCH. THE HIGHER TERRAIN OF WESTERN ASHE AND
WATAUGA COUNTIES NC WILL EXPERIENCE AROUND ONE INCH DURING THIS
TIME FRAME. OTHER SNOWFALL TOTALS WILL BE MAINLY A FEW TENTHS
OVER PARTS OF THE MOUNTAIN EMPIRE REGION OF SOUTHWEST VIRGINIA AND
OTHER PORTIONS OF ASHE AND WATAUGA COUNTY NC.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 400 PM EST MONDAY...
MODELS ARE NOW IN THE SAME BALLPARK FOR THE EXTENDED...JUST NOT SURE
IF THE GAME IS FOOTBALL OR SOCCER. EVOLUTION TO A HIGHLY AMPLIFIED
UPPER PATTERN WITH DEVELOPMENT OF A CLOSED LOW DOING A SIT AND SPIN
OVER THE NORTHEAST US IS A FAVORED SOLUTION THROUGH THE END OF THE
WEEK. BEGIN TO SEE SIGNIFICANT DIFFERENCES AS WE HEAD INTO THE
WEEKEND WITH GFS BEING TYPICALLY MORE PROGRESSIVE AND EURO DIGGING
IN ITS HEELS. BY MONDAY UPPER RIDGE AXIS SHOULD BE CROSSING THE
REGION AS NEXT SOUTHERN STREAM CLOSED LOW APPROACHES FROM THE LOWER
MISSISSIPPI VALLEY.
EVEN WITH THE MODEL DIFFERENCES...IMPACTS ON SENSIBLE WEATHER
ELEMENTS THROUGH THE EXTENDED WILL BE SMALL. NW FLOW UPSLOPE SNOW
SHOWERS ACROSS THE FAR WRN SLOPES OF THE BLUE RIDGE WILL BE WINDING
DOWN THURSDAY NIGHT AS SFC HIGH SLIDES IN FROM THE WEST. MAYBE SOME
FLURRIES FAR WRN SLOPES THROUGH THE END OF THE WEEK...BUT LOOKING
LIKE QUIET WEATHER ELSEWHERE. WE THEN GET INTO SOME WEAK LIFT AS A
LIGHT WARM AIR ADVECTION PATTERN SETS UP SATURDAY NIGHT THROUGH
SUNDAY. THIS MAY BE ENOUGH TO GET SOME SPRINKLES GOING BUT NOTHING
TOO EXCITING...AND GIVEN THE MODEL UNCERTAINTY THIS FAR OUT WILL GO
WITH POPS NO HIGHER THAN SLIGHT CHC CONFINED TO WEST OF THE BLUE
RIDGE. EXPECT A WARMING TREND FROM BELOW NORMAL FRIDAY TO ABOVE
NORMAL BY THE START OF NEXT WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 1150 PM EST MONDAY...
LOW PRESSURE DEVELOPING OFF THE SOUTHEAST WILL SLIDE UP THE
MIDDLE ATLANTIC COAST AND PUSH MOISTURE INTO THE REGION AS IT
GOES. SYSTEM WILL BE PULLING AWAY FROM THE REGION AS E HEAD
TOWARD DAYBREAK AND THIS WILL ALLOW WINDS TO BACK AROUND TO THE
NW. EXPECT WESTERN EDGE OF PRECIPITATION TO REACH KDAN/KROA/KLYH
AROUND 10Z/5AM. UNTIL THEN HIGH CONFIDENCE OF LIFR CEILINGS.
PROLONGED UPSLOPE PATTERN WEST OF THE BLUE RIDGE WITH LOWER
CLOUDS AND SOME SHOWERY PRECIP...WITH DOWNSLOPE AND IMPROVEMENT
EAST OF THE RIDGE WILL DEVELOP BY 18Z. AS THE COASTAL LOW DEEPENS...NW
WINDS WILL BE ON THE INCREASE. LATEST GUIDANCE SUGGESTING MORE
LIGHT PRECIPITATION MAY ROTATE AROUND THE LOW BACK INTO KLYH AND
KDAN TUESDAY AFTERNOON. MODERATE CONFIDENCE WITH THIS SCENARIO.
EXTENDED DISCUSSION...
SNOW SHOWERS AND MVFR UPSLOPE CLOUDS WILL CONTINUE IN SOUTHEAST
WEST VIRGINIA THROUGH THURSDAY MORNING. VFR CONDITIONS ARE
EXPECTED IN THE EAST. GUSTY WINDS ARE LIKELY THROUGH WEDNESDAY
NIGHT.
THURSDAY NIGHT THROUGH SATURDAY...ASIDE FOR SOME LINGERING MVFR
CLOUDINESS IN THE WV MOUNTAINS THURSDAY...HIGH PRESSURE WILL BUILD
OVER THE MID ATLANTIC THURSDAY THROUGH SATURDAY WITH VFR AND
DIMINISHING WINDS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR VAZ014-
017>020-022>024-032>035.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PM/WP
NEAR TERM...AMS/PM/WP
SHORT TERM...DS
LONG TERM...MBS
AVIATION...MBS/PM
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
926 PM PST WED DEC 10 2014
.UPDATE...SHORT TERM AND AVIATION
STORM STILL ON TRACK TO BRING STRONG WINDS TONIGHT AND THURSDAY
WITH HEAVY SNOW TO THE SIERRA LATE THURSDAY INTO FRIDAY. RAIN HAS
MOVED INTO PARTS OF NORTHEAST CA AHEAD OF MAIN STORM WITH NEARLY A
QUARTER INCH AT PLUMAS-EUREKA STATE PARK. MEANWHILE, WINDS WERE
INCREASING WITH GUSTS APPROACHING 90 MPH OVER SIERRA RIDGES AND
GUSTS 30-35 MPH IN SOME LOWER ELEVATION SITES.
A COUPLE OF THINGS TO NOTE WITH THE 00Z GFS/NAM MODEL DATA. 1)
STORM IS ELONGATING A BIT AND THUS THE MODELS ARE SLOWING THE
ARRIVAL OF HEAVIEST PRECIPITATION BY A FEW HOURS PLACING THE
LEADING EDGE IN THE TAHOE BASIN AROUND SUNDOWN TO A COUPLE OF
HOURS LATER ON THURSDAY, AND INTO MAMMOTH AFTER MIDNIGHT, EARLY
FRIDAY. 2) THE PIVOT POINT OF BAND IS A LITTLE FURTHER SOUTH IN
NORTHERN MONO-ALPINE COUNTIES. THIS PIVOT POINT WILL BE THE
LOCATION OF LONGEST DURATION OF SNOWFALL AND THEREFORE THE
HIGHEST SNOWFALL AMOUNTS. CURRENT FORECAST REPRESENTS A 1 TO 2
FEET ACCUMULATION ALONG THE CREST WITH LOCALLY 3 FEET. THE LOCALLY
THREE FEET WILL MOST LIKELY OCCUR NEAR THIS PIVOT POINT.
FOR AVIATION, ONE THING TO WATCH FOR IS ROTORS AT KRNO/KCXP, AS
THE HRRR IS INDICATING SOME LIGHT EAST TO SOUTHEAST WINDS IN THE
MORNING. OUR 06Z TAFS WILL CONTINUE TO INDICATE GRADIENT DRIVEN
WINDS WITH HIGH SUSTAINED WIND SPEEDS. HOWEVER, THERE IS A LOW
CHANCE FOR PERIODS OF ERRATIC WINDS IF THESE ROTORS SET UP OVER
THE AIRPORT. THE NAM WAS SHOWING A RATHER IMPRESSIVE SIGNATURE IN
THE RH FIELDS FROM 700-400MB THURSDAY MORNING ALONG WITH CRITICAL
LAYER WHERE WIND SPEEDS DROPPED TO 25KT AT 500MB. SO PERIODIC
STRONGER DOWNSLOPE GUSTS TO 60KT OR HIGHER ARE POSSIBLE. HOHMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 238 PM PST WED DEC 10 2014/
SYNOPSIS...
A SIGNIFICANT WINTER STORM WILL IMPACT THE REGION TONIGHT THROUGH
FRIDAY. STRONG DAMAGING WINDS ARE LIKELY LATE TONIGHT AND THURSDAY
WITH RAIN AND HEAVY SIERRA SNOW THURSDAY AFTERNOON INTO FRIDAY.
LONG TRAVEL DELAYS ARE LIKELY IN THE SIERRA THURSDAY AND FRIDAY.
CONDITIONS WILL IMPROVE OVER THE WEEKEND AS HIGH PRESSURE BUILDS
OVER THE WEST.
SHORT TERM...
NO BIG CHANGES TO THE FORECAST AS A WINTER STORM MOVES INTO
NORTHEASTERN CALIFORNIA THIS EVENING. INITIAL IMPACT WILL BE A
STRONG TO DAMAGING WIND EVENT STARTING LATE TONIGHT AND
PERSISTING INTO THURSDAY. RAIN AND SNOW WILL BE THE SECOND IMPACT
WITH SIGNIFICANT ACCUMULATIONS IN THE SIERRA THURSDAY AFTERNOON
INTO FRIDAY. HIGH WIND WARNINGS AND WINTER STORM WARNINGS REMAIN
IN EFFECT.
THE MODELS HAVE BECOME A BIT MORE AMPLIFIED AND TRENDED SLIGHTLY
FARTHER WEST WITH THE SYSTEM DUE TO A JET SEGMENT ON THE BACK
SIDE OF THE SYSTEM. THIS IS LEADING TO A MORE SOUTHERLY FLOW
AHEAD OF THE SYSTEM WITH A SLOWER START TIME FOR THE PRECIPITATION
REACHING AREAS SOUTH OF I-80 IN THE SIERRA. THIS IS ALSO SHOWING
UP AS SLIGHTLY LOWER PRECIPITATION (RAIN AND MELTED SNOW) TOTALS
DUE TO LESS FAVORABLE UPSLOPE FLOW ALONG THE SIERRA CREST AND THE
CORE OF THE MOISTURE PLUME REMAINING OVER THE SACRAMENTO/SAN
JOAQUIN VALLEYS.
..WINDS...
HIGH CONFIDENCE IN A STRONG WIND EVENT, DOWNSLOPE SIGNATURES
REMAIN IN THE MODEL DATA WITH PEAK GUSTS OF 50-70 MPH FROM
SURPRISE VALLEY/NORTHERN WASHOE COUNTY, SOUTH INTO EASTERN LASSEN
COUNTY, THE TAHOE BASIN, WESTERN NEVADA AND MONO COUNTY. GUSTS IN WIND
PRONE LOCATIONS ALONG HIGHWAY 395 WILL REACH 70 TO 90 MPH WITH PEAK
SIERRA RIDGE WINDS OF 100-140 MPH. FOR PERSHING, CHURCHILL AND
MINERAL COUNTIES, WINDS WILL INCREASE THURSDAY MORNING WITH AREAS
OF BLOWING DUST OFF THE DRY LAKE BEDS IMPACTING TRAVEL ON I-80,
US-50 AND US-95.
STRONG WINDS WILL START IN THE TAHOE BASIN BY LATE THIS EVENING,
THEN MIX DOWN INTO THE WIND PRONE AREAS ALONG US-395 AROUND SUNRISE
THURSDAY MORNING. THE SLOWER PROGRESSION OF THE SYSTEM MAY ALSO
MEAN A LONGER DURATION OF STRONG TO DAMAGING WINDS INTO THURSDAY
EVENING, ESPECIALLY FOR WESTERN NEVADA.
..PRECIPITATION...
LIGHT RAIN WILL START IN WESTERN LASSEN COUNTY THIS EVENING, THEN
SLOWLY SPREAD SOUTH AND EAST ON THURSDAY. HEAVIEST PRECIPITATION
BAND WILL OCCUR IN LASSEN/PLUMAS/SIERRA COUNTIES THURSDAY
AFTERNOON, IN THE TAHOE BASIN THURSDAY EVENING TO EARLY FRIDAY
MORNING AND THURSDAY NIGHT AND FRIDAY FOR MONO COUNTY. STILL
LOOKING AT 2-3 INCHES OF PRECIPITATION ALONG THE SIERRA CREST,
WITH 1-2 INCHES EAST OF THE CREST TO A LINE FROM SUSANVILLE, TO
THE CARSON RANGE EAST OF LAKE TAHOE, TO HIGHWAY 395 IN MONO
COUNTY.
SNOW LEVELS WILL START AT 6500-7500 FEET NORTH OF US-50 AND
7000-8000 FEET SOUTH OF US-50. SNOW LEVELS WILL GRADUALLY LOWER
THURSDAY AND THURSDAY NIGHT AS HEAVY PRECIPITATION MOVES INTO THE
AREA. SNOW LEVELS SHOULD BOTTOM OUT AT 5000-6000 FEET FRIDAY
MORNING AS THE PRECIPITATION TAPERS OFF TO SHOWERS ON FRIDAY.
NO CHANGE TO THE SNOW AMOUNTS FOR THE SIERRA WITH 1-3 FEET ALONG
THE SIERRA AND 6-14 INCHES BETWEEN 6000 AND 7000 FEET, INCLUDING
THE TAHOE BASIN. PLEASE REFER TO THE WINTER STORM WARNINGS FOR
DETAILS ON SNOW AMOUNTS. SNOW RATIOS IN THE HEAVY PRECIPITATION
BAND WILL STAY ON THE LOW SIDE, RANGING FROM 8:1 TO 10:1, DUE TO
THE LACK OF COLD AIR. HOURLY SNOW RATES MAY ALSO PEAK AT 2-3
INCHES PER HOUR ALONG THE CREST THURSDAY EVENING TO FRIDAY
MORNING. WHITEOUT CONDITIONS ARE LIKELY OVER THE SIERRA PASSES
THURSDAY EVENING TO FRIDAY MORNING.
FOR WESTERN NEVADA BEST CHANCE FOR RAIN AND SNOW IS THURSDAY NIGHT
AS THE SLOW MOVING FRONT SWINGS INLAND WITH SHOWERS PERSISTING
THROUGH FRIDAY. SNOW LEVELS SHOULD REMAIN ABOVE 5000 FEET, WITH
LIGHT ACCUMULATIONS POSSIBLE IN THE FOOTHILLS AND VIRGINIA CITY
HIGHLANDS ABOVE 5500 FEET.
ONE SIDE NOTE...IF THE MODELS CONTINUE TO TREND TO THE WEST WITH
THE MAIN MOISTURE PLUME, THEN PRECIPITATION TOTALS EAST OF THE
SIERRA CREST COULD BE MUCH LESS THAN LISTED ABOVE. BRONG
LONG TERM...SATURDAY THROUGH WEDNESDAY...
THE MAIN AREA OF LOW PRESSURE WILL BEGIN TO EXIT THE REGION ON
SATURDAY, BUT THERE IS A SLIGHT CHANCE FOR LIGHT SHOWERS TO LINGER.
SHORTWAVE RIDGE FOLLOWS ON SUNDAY WITH TEMPERATURES ALOFT WARMING
AND THE AIR MASS DRYING AND BECOMING STABLE. WITH WEAK INVERSIONS IN
PLACE, MIXING WILL BE POOR AND EXPECT THAT LOWER ELEVATION VALLEYS
WILL BE SLOW TO WARM. THEREFORE HAVE KEPT HIGH TEMPERATURES NEAR TO
SLIGHTLY BELOW NORMAL SATURDAY AND SUNDAY.
AN ELONGATED AREA OF LOW PRESSURE APPROACHES THE WEST COAST MONDAY,
MOVING INLAND DURING THE DAY BASED ON THE GFS, OR MONDAY NIGHT BASED
ON THE EC. THESE ARE BOTH SLIGHTLY FASTER THAN THE MODEL RUNS
YESTERDAY. THIS SYSTEM IS FAIRLY DISJOINTED AND DOES NOT APPEAR
TO HAVE ENOUGH ORGANIZATION TO BRING SIGNIFICANT PRECIPITATION TO
THE REGION, ESPECIALLY WITH A POSSIBLE SPLIT OF THE LOW AS THE JET
DIGS SOUTH. EVEN SO, ADDITIONAL LIGHT RAIN AND SNOW IS POSSIBLE
FOR MONDAY INTO TUESDAY, WITH THE BEST CHANCES ALONG THE SIERRA
AND ACROSS NORTHERN WASHOE COUNTY. THE EC IS QUICK TO BRING A
SECONDARY SHORTWAVE ACROSS NORTHERN CALIFORNIA/NEVADA WEDNESDAY,
WHICH IS SIMILAR TO THE 06Z GFS. THE 12Z GFS, HOWEVER, DAMPENS THE
AMPLITUDE OF THE WAVE AND KEEPS IT FARTHER NORTH, WHICH WOULD NOT
BRING AS MUCH PRECIPITATION TO THE REGION. HAVE KEPT CHANCES FOR
PRECIPITATION IN THE FORECAST THROUGH THE PERIOD TO ACCOUNT FOR
ANY UNCERTAINTY, ESPECIALLY BECAUSE THE PATTERN LOOKS TO REMAIN
UNSETTLED THROUGH THE END OF NEXT WEEK. DJ
AVIATION...
WINDS WILL BEGIN TO INCREASE THIS AFTERNOON AND EVENING BECOMING
STRONG AND GUSTY BY THURSDAY MORNING AS AN AREA OF LOW PRESSURE
APPROACHES THE SIERRA AND NORTHWEST NEVADA. THIS HAS THE POTENTIAL
TO BE THE STRONGEST WIND EVENT THE AREA HAS SEEN IN SEVERAL YEARS.
SOUTHERLY WINDS SUSTAINED 35 TO 45 KTS WITH GUSTS 55 TO 70 KTS
AND RIDGE GUSTS OVER 100 KTS ARE POSSIBLE FOR MUCH OF THE SIERRA AND
WESTERN NEVADA. PEAK WINDS FOR AIRPORTS NORTH OF HIGHWAY 50,
INCLUDING KRNO, KTVL, KTRK, AND KCXP WILL BE APPROXIMATELY AROUND 4
AM THROUGH 6 PM THURSDAY. SOUTH OF THERE, INCLUDING KMMH, THE
STRONG WINDS WILL POSSIBLY LAST THROUGH MIDNIGHT. WINDS ARE FAIRLY
UNIDIRECTIONAL, MAKING DIRECTIONAL LLWS LESS OF A CONCERN,
HOWEVER, SPEED SHEAR IS POSSIBLE, ESPECIALLY BELOW 5000 FEET AGL.
SIGNIFICANT TURBULENCE IS LIKELY ALONG WITH BLOWING DUST ACROSS
THE CARSON SINK.
THIS STORM WILL ALSO BRING MOUNTAIN SNOW AND VALLEY RAIN TO THE AREA
LATE TONIGHT INTO FRIDAY. EXPECT PRECIPITATION TO REACH NORTHEAST
CALIFORNIA LATE TONIGHT, SPREADING INTO THE SIERRA THURSDAY MORNING
AND INTO WESTERN NEVADA THURSDAY NIGHT. 4 TO 10 INCHES OF TOTAL SNOW
ACCUMULATION IS LIKELY ON THE RUNWAYS AT KTRK, KTVL, AND KMMH, WITH
THE POTENTIAL FOR MORE IF SNOW LEVELS DROP QUICKER. THE COMBINATION
OF WIND AND SNOW COULD MAKE FOR NEAR WHITE OUT CONDITIONS ON
APPROACH INTO SIERRA AIRPORTS, ESPECIALLY THURSDAY NIGHT WHEN
SNOWFALL RATES IN THE HIGH SIERRA COULD REACH 1-3 INCHES PER HOUR.
FOR NORTHWEST NEVADA, LOWER CIGS AND RAIN WILL BRING PERIODS OF
MVFR-IFR CONDITIONS ALONG WITH TERRAIN OBSCURATION. DJ
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY NVZ003-005.
HIGH WIND WARNING UNTIL 1 PM PST THURSDAY NVZ002.
WINTER STORM WARNING FROM 1 PM THURSDAY TO 1 PM PST FRIDAY
NVZ002.
WIND ADVISORY FROM 4 AM THURSDAY TO 4 AM PST FRIDAY NVZ001-004.
CA...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY CAZ070-071.
WINTER STORM WARNING FROM 10 AM THURSDAY TO 10 AM PST FRIDAY
ABOVE 5000 FEET FOR CAZ071.
HIGH WIND WARNING UNTIL 4 PM PST THURSDAY CAZ073.
WINTER STORM WARNING FROM 4 PM THURSDAY TO 4 PM PST FRIDAY
CAZ073.
HIGH WIND WARNING UNTIL 1 PM PST THURSDAY CAZ072.
WINTER STORM WARNING FROM 1 PM THURSDAY TO 1 PM PST FRIDAY
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1207 AM EST THU DEC 11 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 341 PM EST WED DEC 10 2014
A QUIET WEATHER PATTERN WILL BE PLACE OVER CENTRAL INDIANA WITH
SLOWLY WARMING TEMPERATURES AND DRY CONDITIONS THROUGH THE WEEKEND.
THE NEXT CHANCE FOR PRECIPITATION WILL ARRIVE ON MONDAY WITH LOW
PRESSURE MOVING THIS WAY FROM THE PLAINS AND TEMPERATURES LOOK WARM
ENOUGH FOR THIS TO BE RAIN.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 950 PM EST WED DEC 10 2014
.UPDATE...SATELLITE LOOPS INDICATED PARTIAL CLEARING HAS REACHED THE
COUNTIES JUST NORTHEAST OF MUNCIE AND KOKOMO AT 02Z AND RAP 925 MB
RH FIELDS INDICATE DRIER AIR SHOULD SPREAD INTO NORTHEAST AND EAST
CENTRAL PARTS OF OUR FORECAST AREA OVERNIGHT AND INTO THURSDAY.
AS A RESULT WILL FOLLOW THIS TREND TO INDICATE PARTIAL CLEARING
ACROSS OUR NORTHEAST AND EAST CENTRAL SECTIONS LATER TONIGHT.
RAP INDICATES THE WESTERN HALF OF OUR REGION SHOULD REMAIN CLOUDY
OVERNIGHT. LOWERED MINIMUM TEMPERATURES A FEW DEGREES TONIGHT IN
AREAS WHERE SOME CLEARING IS EXPECTED. OTHERWISE...LITTLE CHANGE TO
THE REST OF THE FORECAST.
PREVIOUS NEAR TERM DISCUSSION FOLLOWS...
SATELLITE LOOP INDICATES SOME SCATTERING/CLEARING COULD WORK ITS
WAY IN FROM THE NORTH EARLY TONIGHT. HOWEVER CYCLONIC
FLOW...AMPLE LOW LEVEL MOISTURE AND TRAPPING INVERSION WILL NOT
ALLOW THIS TO LAST FOR LONG. EXPECT THESE CONDITIONS TO CAUSE ANY
AREAS THAT CLEAR TO FILL BACK IN WITH CLOUDS AND THUS KEPT MOSTLY TO
COMPLETELY CLOUDY SKIES OVER THE AREA THROUGH THE NIGHT. LEANED
WARMER THAN GUIDANCE BY A COUPLE DEGREES DUE TO EXPECTED CLOUD COVER.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 950 PM EST WED DEC 10 2014
.UPDATE...OVER AREAS THAT CLEAR TONIGHT...MODEL SOUNDINGS INDICATE
CONTINUED DRYING IN LOWER LEVELS SHOULD CONTINUE INTO THURSDAY.
THUS IT SEEMS UNLIKELY THAT CLOUDS WILL RETURN OVER NORTHEAST OR
EAST CENTRAL SECTIONS ON THURSDAY. AS A RESULT...DECIDED TO UPDATE
SKY COVER GRIDS FOR THURSDAY TO REELECT THIS TREND. LEFT WESTERN
SECTIONS UNCHANGED AS FLOW OFF OF LAKE MICHIGAN MAY KEEP CLOUDS
THERE.
PREVIOUS SHORT TERM DISCUSSION FOLLOWS...
MODELS ARE IN GOOD AGREEMENT AND GENERALLY USED A CONSENSUS WITH THE
EXCEPTION OF CLOUD COVER...WHICH THE MODELS AND GUIDANCE TEND TO
CLEAR MUCH TOO QUICKLY IN THIS PATTERN. FOR THURSDAY AND THURSDAY
NIGHT...EVEN THOUGH HIGH PRESSURE IS TRYING TO BUILD IN...TRAPPING
INVERSION OVER HIGH LOW LEVEL MOISTURE SHOULD KEEP STRATUS DECK IN
PLACE OVER THE AREA FOR MOSTLY CLOUDY SKIES LASTING INTO THURSDAY
NIGHT. COULD SEE SOME SCATTERING THURSDAY NIGHT BUT THEN FILLING
BACK IN TO MOSTLY CLOUDY BY FRIDAY AFTERNOON FOR PARTS OF THE AREA.
WITH UPPER RIDGING BUILDING TOWARD THE AREA AND HIGH PRESSURE EXPECT
DRY CONDITIONS. FOR TEMPERATURES LEANED CLOSER TO RAW MODEL NUMBERS
WITH COOLER HIGHS AND WARMER LOWS DUE TO CLOUD COVER. SHOULD STILL
SEE A SLOW WARMING TREND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 156 PM EST WED DEC 10 2014
UPCOMING PRECIP LOOKS TO MOVE THROUGH THE AREA AS A CLOSED LOW
MONDAY INTO TUESDAY. ENSEMBLES HAVE PRETTY GOOD CONSENSUS ON THIS
EVENT SO POPS WERE INCREASED TO JUST SHY OF LIKELY. OTHERWISE WARMER
THAN NORMAL TEMPS TO BEGIN THE PERIOD WILL END UP NORMAL TO BELOW
NORMAL BY MID WEEK NEXT WEEK. ALLBLEND GUIDANCE SEEMED TO INITIALIZE
THIS PATTERN WELL AND DID NOT NEED TO ALTER THE FORECAST TOO MUCH.
&&
.AVIATION /DISCUSSION FOR THE 11/0600Z TAF ISSUANCE/...
ISSUED AT 1141 PM EST WED DEC 10 2014
PERSISTENT INVERSION CONTINUES TO PREVENT CLOUDS FROM SCATTERING
OUT. AS A RESULT...MVFR CONDITIONS WILL CONTINUE THROUGH WED 15Z.
AT THAT POINT...THERE SHOULD BE IMPROVEMENT TO VFR CATEGORY WITH
MORE RAPID CLEARING THIS AFTERNOON. WINDS WILL GENERALLY BE
WEST/NORTHWESTERLY AT 5 TO 10 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/JH
SHORT TERM...CP/JH
LONG TERM....SMF
AVIATION...TDUD
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AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
309 AM EST THU DEC 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM EST THU DEC 11 2014
07Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING INTO KENTUCKY...THOUGH
A LAYER OF STRATOCU CLOUDS REMAIN...BLANKETING THE CWA AND KEEPING
TEMPERATURES FROM FALLING OFF TOO FAST THIS NIGHT. READINGS AT 2 AM
VARIED FROM THE UPPER 20S ON THE RIDGES TO THE LOWER 30S IN THE
VALLEYS WHILE DEWPOINTS HAD FALLEN TO THE LOWER 20S FOR MOST OF THE
AREA. CAA CONTINUES ON NORTH TO NORTHWEST WINDS OF 5 TO 10 KTS...WITH
A COUPLE OF HIGHER GUSTS NOTED ON THE RIDGES.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT FOR THE SHORT TERM
PORTION OF THE FORECAST AS THEY ALL DEPICT THE BLOCKING LOW IN PLACE
OVER SOUTHERN NEW ENGLAND ONLY SLOWLY PIVOTING AWAY TO THE NORTHEAST
THROUGH THE PERIOD. LOCALLY...THIS WILL ALLOW HEIGHTS TO GRADUALLY
RISE OVER EASTERN KENTUCKY...BUT NOT BEFORE ONE FINAL BATCH OF ENERGY
SHIFTS SOUTHEAST OF THE AREA THIS MORNING. OTHERWISE...A QUIET
PATTERN WILL ENSUE WITH LITTLE IN THE WAY OF ENERGY AFFECTING THE
STATE IN NORTH TO NORTHWEST FLOW LATER TODAY AND THROUGH THE DAY
FRIDAY. GIVEN THE MODEL AGREEMENT HAVE FOLLOWED THE HIGHER RESOLUTION
NAM12 AND HRRR MOST CLOSELY FOR WX DETAILS IN THE SHORT TERM.
THE MAIN QUESTION TODAY WILL BE HOW QUICKLY THE LOW CLOUDS IN PLACE
OVER THE AREA WILL BREAK UP. THE TIME HEIGHTS FROM THE NAM SUGGESTS
THAT THEY WOULD LINGER INTO THE AFTERNOON...HOWEVER...THE RECENT
SATELLITE LOOP SHOW CLEARING PUSHING QUICKLY SOUTH FROM NORTHERN
OHIO. ACCORDINGLY...HAVE BROUGHT THE LOWER PERCENTAGES OF CLOUD
COVER INTO EAST KENTUCKY A BIT SOONER THAN THE PREVIOUS FORECAST AND
THE NAM12 DEPICTION. OTHERWISE...MOSTLY CLEAR SKIES WILL BE THE RULE
THROUGH FRIDAY ONCE THAT DRIER AIR MOVES INTO THE CWA. THIS WILL LEAD
TO A SMALL TO MODERATE RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT...
WITH THE HIGH CENTER JUST TO THE WEST OF THE CWA. ONLY A SLOW
MODERATION OF THIS HIGH CAN BE EXPECTED SO HIGHS TODAY AND TOMORROW
WILL STILL BE ON THE CHILLY SIDE OF NORMAL...THOUGH FRIDAY WILL BE
SEVERAL DEGREES WARMER THAN TODAY WITH MORE SUNSHINE.
USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND GRIDS WITH
SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT. AS FOR POPS AND WX...
KEPT THEM LOW AND NON-EXISTENT THROUGH FRIDAY GIVEN THE HIGH PRESSURE
REGIME NOW IN PLACE...IN LINE WITH MOS GUIDANCE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 AM EST THU DEC 11 2014
THERE WAS GOOD MODEL AGREEMENT IN THE EXTENDED PORTION OF THE
FORECAST. BOTH THE GFS AND ECMWF BEGIN THE PERIOD WITH A LARGE RIDGE
OF HIGH PRESSURE SITUATED ACROSS A LARGE PORTION OF THE CENTRAL AND
EASTERN CONUS FROM FRIDAY NIGHT THROUGH MONDAY. THIS RIDGE LOOKS TO
BE QUITE STRONG AND THE MODELS DO NOT BEGIN MOVING IT OFF TO THE
EAST UNTIL MONDAY NIGHT...AS A FAIRLY WELL DEVELOPED AREA OF LOW
PRESSURE TAKES SHAPE OVER THE CENTRAL PLAINS. AS THIS SYSTEM BEGINS
TO MOVE EAST...THE RIDGE WILL FINALLY BEGIN TO GIVE GROUND AND MOVE
OFF TO OUR EAST AND EVENTUALLY THROUGH THE MID ATLANTIC REGION AND
OUT TO SEA BY EARLY TUESDAY MORNING. AS THE CENTRAL PLAINS
APPROACHES...CLOUD COVER WILL BE ON THE INCREASE MONDAY AFTERNOON
AND EVENING. TEMPERATURES WILL WARM UP QUITE NICELY ON MONDAY...AS
SOUTHERLY WINDS AHEAD OF THE APPROACHING SYSTEM BRING WARM MOIST AIR
OFF THE GULF OF MEXICO INTO THE REGION. BASED ON THE LATEST TIME
HEIGHT CROSS SECTIONS...IT APPEARS THAT PRECIPITATION ONSET WILL
HOLD UNTIL AROUND 0Z ON TUESDAY...OR UNTIL THE SHORTWAVE MOVES OUT
OF THE CENTRAL MISSISSIPPI VALLEY REGION AND ACROSS THE OHIO AND
TENNESSEE VALLEYS. THE WAVE LOOKS TO BE FAIRLY PROGRESSIVE...WITH
THE BEST CHANCES FOR RAIN OCCURRING MONDAY NIGHT AND TUESDAY.
UPSLOPE FLOW AND RESIDUAL MOISTURE BEHIND THE DEPARTING LOW WILL
KEEP A CHANCE OF SCATTERED RAIN SHOWERS IN THE FORECAST THROUGH
WEDNESDAY MORNING.
TEMPERATURES TO BEGIN THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL...WITH FORECAST HIGHS ON SATURDAY AND SUNDAY TOPPING OUT IN
THE MID 40S. MONDAY LOOKS TO BE WARMER THAN NORMAL IN THE RETURN
FLOW OFF THE GULF...WITH HIGHS ON MONDAY EXPECTED TO RISE INTO THE
LOW TO MID 50S ACROSS THE AREA. THE WEATHER WILL BE SLIGHTLY COOLER
ON TUESDAY DUE TO WIDESPREAD CLOUD COVER AND PRECIPITATION. HIGHS ON
MONDAY ARE EXPECTED TO TOP OUT AROUND 50. ONCE WINDS SHIFT TO THE
NORTHWEST BEHIND THE DEPARTING SYSTEM...COLDER AIR WILL BEGIN TO
SPILL INTO THE AREA...ALLOWING FOR HIGHS IN THE LOW TO MID 40S ON
WEDNESDAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 20S AND LOWER 30S
FRIDAY THROUGH SUNDAY NIGHT...BEFORE CLOUD COVER MOVES BACK IN AND
WINDS SHIFT TO THE SOUTH. THE MERCURY WILL NOT FALL AS MUCH MONDAY
NIGHT AND TUESDAY NIGHT DUE TO THE INFLUENCE OF CLOUD COVER AND
SOUTHERLY WINDS. LOWS THOSE TWO NIGHTS SHOULD ONLY FALL INTO THE
UPPER 30S FOR MOST FOLKS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1240 AM EST THU DEC 11 2014
NORTHWEST FLOW WILL TEND TO KEEP THE LOW STRATOCU DECK IN PLACE
THROUGH THE FIRST PART OF THE TAF FORECAST. CIGS WILL HOLD JUST ON
THE MVFR SIDE OF THE LINE AROUND 2500 FEET. AFTER SUNRISE...CIGS ARE
EXPECTED TO TREND TOWARDS IMPROVING CONDITIONS AND VFR TERRITORY
BEFORE BREAKING UP COMPLETELY INTO EARLY AFTERNOON. WINDS WILL
GENERALLY FLOW OUT OF THE NORTHWEST THROUGH THE PERIOD AT AROUND 5
KTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
308 AM EST Thu Dec 11 2014
.SHORT TERM (Now through Friday)...
Issued at 304 AM EST Thu Dec 11 2014
Clouds are again the main challenge with this forecast package.
Overcast conditions continued early this morning across southern
Indiana and central Kentucky. However, dry low level air was
punching from Quebec through Michigan into Indiana and Ohio on the
back side of cyclonic circulation over New England. By 3am the
clearing line had made it down to the I-70 corridor from
Indianapolis to Columbus. The HRRR has been doing the best job
overnight with this clearing line, with some support from 0.5km RH
progs from the GFS. These models bring the clearing line into
central and eastern parts of the LMK CWA over the course of the day,
and we`ll time it as such in the grids. West of I-65 is more of a
question mark, with models wanting to clear skies there as well but
satellite showing less clearing and more cloudiness upstream of
those areas. So, will hold on to the clouds longer in the west than
in the east.
High temperatures today should be around 40 degrees with northwest
breezes this morning becoming westerly this afternoon.
Tonight high pressure will build into the middle Mississippi and
lower Ohio Valleys. The models clear our skies out, which normally
makes sense with domes of high pressure. However, the high is
currently over the upper Mississippi Valley where it`s...cloudy.
So, there is some question whether or not we`ll really clear out
tonight. Even the wetter model solutions give us mostly clear
skies, though, so will lean on the side of fewer clouds for the
overnight hours at this time. It will be interesting to watch the
clouds to our northwest today to see if they slide southeast along
with the high or not. Big potential for a busted forecast tonight
re: sky cover.
Low temperatures tonight will depend a lot on how much cloud we end
up with. For now will stick with mid 20s. Warmer if we stay cloudy.
On Friday that high pressure system will be right on top of us,
giving us partly cloudy skies and high temperatures in the middle
and upper 40s with light winds.
.LONG TERM (Friday Night through Wednesday)...
Issued at 235 AM Thu Dec 11 2014
The upper level pattern by Friday night is expected remain highly
amplified across the CONUS, with a closed low across New England and
a deepening shortwave trough pushing into California. In between,
the blocking pattern will enhance the ridge through the central
Plains into southern Canada. At the surface, high pressure will
remain across the Mid-Mississippi and Ohio River Valleys.
Forecast challenge Friday night into Saturday is focused on cloud
cover and its impacts on temperatures. Despite very dry air above
850 mb, we`ll be dealing with some low-level moisture issues. 11.00z
guidance, particularly the NAM and GEM, suggest a strong inversion
sets up through about 925 mb, or the lowest 2500 ft, with increasing
saturation Friday night. A stratus deck would push into the region
from Upper MS River Valley based on model RH fields and would
persist through the day on Saturday. SREF probabilities for this
deck developing are currently running at or above 70 percent,
especially across the northern half of the local area. Models this
time of year struggle with low-level moisture, but given the
environmental setup, the fact that stratus is already present across
much of the central and northern Plains and the majority of the
models showing this solution, confidence is higher than average. As
such, increased cloud cover during this period and tempered the
diurnal temperature trend as well, favoring the warmer guidance for
Saturday morning lows and cooler guidance for highs.
Going into Sunday, clouds will once again be the main issue to deal
with across the Ohio Valley. Soundings differ in terms of the
strength, but all show the low level inversion remaining in place
around 925 mb, strongest along the KY/IN border and points north.
The surface high and upper level ridge axis are expected to be
directly over the region, resulting in an impressive light wind
layer /less than 10 kts through 25 kft/. If stratus is around, there
won`t be much wind to push/scour/mix it out. Again, increased cloud
cover some and lowered highs/raised lows, especially north of the KY
parkways.
By early next week, the major West Coast storm system will move
across the southern Plains and lift toward the Ohio Valley. The last
several cycles of model runs have shown high variability in the
track of this system, but the 11.00z runs seem to have come
together, bringing the system through Missouri and right across
KY/IN. Rain chances will spread in Monday, becoming likely Monday
night into Tuesday morning, then clearing out late Tuesday.
Confidence continues to increase, so POPs were adjusted higher. In
the wake of this system, a period of drier weather and seasonable
temperatures looks likely followed by the possibility of another
southern stream storm system for late next week into the following
weekend.
&&
.AVIATION (06Z TAF Update)...
Issued at 1230 AM EST Thu Dec 11 2014
Clouds remain the main TAF problem. High-end MVFR ceilings
continue to dominate from the Missouri Valley through the Ohio
Valley to New England. However, dry air around 800m streaming
from eastern Canada into the Great Lakes is starting to punch
southward behind the big East Coast storm`s circulation. While the
main thrust of this dry air will be into Ohio for the next several
hours, eventually it should make it down to LEX, and then SDF, and
then BWG over the course of the day. Attempting to time clearing of
stratus is fraught with peril, but going on satellite trends and the
HRRR (which verified very well at 04Z with the clearing line), will
bring VFR conditions into the northern TAF sites late this morning,
and to BWG by mid afternoon. The remainder of the TAF period will
then be quiet.
Surface winds will come in from the northwest this morning, shifting
to the west at 5 to 10 knots this afternoon ahead of a dome of high
pressure over the middle Mississippi Valley.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........13
Long Term.........ZBT
Aviation..........13
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1201 AM EST THU DEC 11 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 332 PM EST WED DEC 10 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG
STRETCHING FM THE DESERT SW NEWD TOWARD HUDSON BAY...SUPPORTING A
SFC RDG AXIS FM JAMES BAY SWWD INTO WI. LOCAL 12Z RAOBS UNDER THIS
RDG AXIS SHOW A SHARP INVRN BTWN ABOUT H925 AND H95...WITH HI RH BLO
THIS SHARP INVRN. SFC OBS/STLT IMAGERY INDICATE THE LO CLDS HAVE
FINALLY DISSIPATED OVER UPR MI CLOSER TO THE CORE OF DRIER LLVL AIR
IN ONTARIO. THE LO CLD IS MORE EXTENSIVE OVER MN AND THE SW HALF OF
WI...CLOSER TO SOMEWHAT HIER INVRN TO H9/DEEPER LLVL MSTR SHOWN ON
THE 12Z MPX RAOB. THERE ARE SOME HI CLDS STREAMING ACRS THE CWA IN
THE NNW FLOW E OF UPR RDG AXIS...BUT THE 12Z INL/YPL RAOBS ARE SO
DRY IN THE MID LVLS THESE CLDS ARE THIN...AND THERE IS NO PCPN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LO CLD TRENDS/IMPACT
ON TEMPS.
TNGT...AS THE SFC HI PRES CENTER NEAR JAMES BAY SHIFTS TO THE NE...
ANOTHER HI CENTER AT THE SW EDGE OF THE RDG AXIS OVER WI IS PROGGED
TO BECOME THE DOMINANT FEATURE ON THE LLVL WIND FIELD OVER THE UPR
LKS. THE RESULT WL BE A SHIFT IN LLVL WIND DIRECTION TO A MORE W-NW
FLOW. THIS CHANGE SHOULD ALLOW A RETURN OF THE MORE EXTENSIVE LO
CLDS NOW DOMINATING MN AND WRN LK SUP. THE LO CLDS WL SLOWEST IN
RETURNING TO THE E AND SCENTRAL CWA...SO EXPECT THE LOWEST MIN TEMPS
NEAR THE LO END OF GUIDANCE IN THIS AREA. SINCE THESE LO TEMPS ARE
FCST TO FALL THRU FAIRLY HI DEWPTS OBSVD THIS AFTN WITH LGT WINDS
UNDER THE HI PRES RDG...ADDED SOME FOG TO SOME PLACES IN THESE
AREAS. ALSO OPTED TO INCLUDE A MENTION OF SOME FLURRIES/FREEZING DZ
OVER THE KEWEENAW LATE WITH A MORE PRONOUNCED UPSLOPE W WIND
COMPONENT WITHIN SHALLOW MSTR WEDGE/ LOWEST TEMPS NEAR -7C AT LO
INVRN BASE INADEQUATE TO ENSURE ICE CRYSTAL FORMATION.
THU...WITH LLVL NW FLOW REMAINING IN PLACE UNDER PERSISTENT UPR
RDG/LARGE SCALE SUBSIDENCE...EXPECT THE MOST LO CLD COVER IN AREAS
OVER THE W AND E DOWNWIND OF LK SUP. LINGERING FOG/FREEZING DZ AND
FLURRIES EARLY IN THE DAY SHOULD DISSIPATE BY LATE MRNG. THE
SCENTRAL CWA INFLUENCED BY THE DOWNSLOPE NW FLOW WL SEE THE MOST
SUNSHINE. MIXING TO JUST H925 YIELDS HI TEMPS RISING INTO THE 30S IN
THESE AREAS THAT HAVE MORE SUN...BUT MAX TEMPS SHOULD BE LOWER WHERE
THERE ARE MORE CLDS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 402 PM EST WED DEC 10 2014
THE ANOMALOUS UPPER RIDGE WILL BE OVER THE UPPER MISSISSIPPI VALLEY
AT THE START OF THE LONG TERM PERIOD AND SLOWLY SHIFT EAST ACROSS
THE UPPER GREAT LAKES REGION THROUGH THE FIRST HALF OF THE WEEKEND.
IN FACT...00Z NAEFS ENSEMBLE MEAN 500MB HEIGHT VALUES EXCEED
ANYTHING SEEN DURING THIS TIME OF YEAR BETWEEN 1979-2009 ON THE
CFSR. THUS...THE AREA WILL BE EXPERIENCING ABOVE NORMAL TEMPERATURES
DURING THAT PERIOD. THE HIGH PRESSURE RIDGE THAT WILL BE OVER THE
AREA TO START THE PERIOD (FROM A HIGH CENTERED IN THE MID
MISSISSIPPI VALLEY) WILL BE SLOWLY SINKING SOUTHEAST THROUGH THE
SOUTHEASTERN STATES THROUGH SATURDAY LEADING TO THE RIDGE TO
LOOSEN ITS GRIP ON THE AREA. BEFORE THAT OCCURS...THAT WARMING
PERIOD WILL SEE HIGHS GRADUALLY RISING THROUGH THE 30S FOR THE REST
OF THE WEEK AND IN THE UPPER 30S AND LOWER 40S ON SATURDAY. THE ONE
ITEM OF CONCERN DURING THIS PERIOD WILL BE THE POTENTIAL FOR LOW
CLOUDS BENEATH THE SUBSIDENCE INVERSION. ALTHOUGH THE AREA BROKE
OUT OF THE LOW CLOUDS TODAY...THE MODELS ARE INDICATING THE LOW
CLOUDS OVER MINNESOTA TO REMAIN IN PLACE AND SLOWLY SHIFT BACK
TOWARDS THE AREA THURSDAY NIGHT INTO FRIDAY AS THE RIDGE AXIS
SHIFTS THROUGH. THERE IS STILL SOME MODEL VARIABILITY IN THE
SOLUTIONS WITH THIS...BUT LIKE THE IDEA SHOWN BY THE PREVIOUS SHIFT
WITH GENERALLY MOSTLY CLOUDY CONDITIONS MOVING OVER THE AREA ON
THURSDAY NIGHT AND THEN GRADUALLY DIMINISHING ON FRIDAY.
AS THE RIDGE BEGINS TO SHIFT EAST OF THE AREA ON
SATURDAY...SOUTHWESTERLY FLOW WILL BEGIN TO DEVELOP OVER THE AREA
AND PULL ABUNDANT LOW LEVEL MOISTURE OVER THE U.P. FOR SATURDAY
NIGHT AND CONTINUING UNTIL A SURFACE TROUGH SWEEPS THROUGH THE AREA
SUNDAY NIGHT INTO MONDAY MORNING. THAT WILL LEAD TO A GENERALLY
DREARY PERIOD WITH LOW CLOUDS AND OCCASIONAL DRIZZLE/FOG. WILL LEAN
ON THE BETTER PERFORMING RAW MODEL GUIDANCE (IN THESE LOW CLOUD
SITUATIONS) FOR OVERNIGHT LOWS THIS WEEKEND...WHICH SHOULD KEEP
TEMPERATURES AT OR ABOVE FREEZING FROM SATURDAY THROUGH SUNDAY
NIGHT. THUS...IF ANY DRIZZLE OCCURS IT SHOULD STAY IN LIQUID FORM
UNLESS IF FALLS ON ANY UNTREATED OR EXISTING COLD SURFACES.
THE ELONGATED SURFACE TROUGH (STRETCHING FROM A LOW IN THE CENTRAL
PLAINS TO ANOTHER LOW NEAR JAMES BAY) WILL SHIFT THROUGH THE AREA
LATE SUNDAY NIGHT INTO MONDAY MORNING. THIS WILL LEAD TO COLDER AIR
GRADUALLY SHIFTING INTO THE AREA MONDAY INTO MONDAY NIGHT. AS THE
COLDER AIR MOVES INTO THE AREA...WILL SHOW A WEST/EAST TRANSITION TO
MORE FROZEN PRECIPITATION MONDAY INTO MONDAY EVENING. DEPENDING
ON THE TIMING OF THE COLD AIR ARRIVAL...MAY BE SOME STRUGGLE FOR ICE
CRYSTALS INITIALLY UNTIL THE DEEPER MOISTURE AND COLDER AIR
ARRIVE...GENERALLY ON MONDAY NIGHT.
ONE INTERESTING ITEM FOR THE FIRST PART OF NEXT WEEK IS THE
INTERACTION OF THE SHORTWAVE TIED TO THE SURFACE LOW MOVING
OUT OF THE CENTRAL PLAINS AND ANOTHER DROPPING SOUTHEAST OUT OF
CENTRAL CANADA. THE MODELS VARY ON THE HANDLING OF THESE WAVES
TUESDAY INTO WEDNESDAY...BUT EITHER WAY IT APPEARS THAT THERE WILL
BE LINGERING UPPER LEVEL ENERGY AND SURFACE TROUGH OVER THE GREAT
LAKES REGION FOR TUESDAY AND DEPARTING WEDNESDAY (WHILE AN
AREA OF HIGH PRESSURE MOVES INTO THE UPPER MISSISSIPPI VALLEY).
THESE VARYING SOLUTIONS LEAD TO A WIDE VARIETY OF IDEAS ON WHEN THE
COLD AIR MOVES IN AND HOW COLD THE 850MB TEMPS WILL BE TUESDAY INTO
WEDNESDAY. LOOKING AT THE 850MB TEMP ENSEMBLE MEMBERS/MEAN...THERE
IS AN EXTREMELY LARGE SPREAD IN GEFS MEMBERS WITH THE MEAN
SIGNIFICANTLY WARMER THAN THE 12Z GFS. THE 00Z ECMWF ENSEMBLE MEAN
ALSO SHOWS A LITTLE WARMER IDEA FOR THAT PERIOD...BUT THEN THE 12Z
ECMWF TRENDED COLDER AND TOWARDS THE 12Z GFS. WITH MODELS USUALLY
STRUGGLING ON THE INTERACTION OF SHORTWAVES AT THAT TIME
RANGE...HAVE LOW CONFIDENCE IN THE FORECAST FOR EARLY NEXT WEEK AND
WILL FOLLOW A GENERAL CONSENSUS (ALTHOUGH SLIGHTLY WARMER LOW LEVEL
TEMPS) THAN SHOWN BY THE RAW MODELS. THEREFORE...WILL SHOW LOW END
CHANCE POPS TO SHOW THE POTENTIAL FOR LES. IF THE COLDER
TEMPERATURES PAN OUT AND WITH NORTHERLY FLOW IN PLACE...COULD SEE
PERIODS OF STRONGER LAKE EFFECT SNOW IN THOSE SNOW BELTS TUESDAY
INTO WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1201 AM EST THU DEC 11 2014
THE LOWEST LIFR CONDITIONS WITH SOME FZDZ/ FLURRIES WL IMPACT CMX
LATE TNGT/THU MRNG...WHEN AND WHERE THE W WIND WL PRESENT A SHARPER
UPSLOPE WIND COMPONENT. WITH A DOWNSLOPE WIND...SAW HAS THE BEST
CHANCE TO AVOID THE LOWER CONDITIONS FOR A LONGER TIME AND WILL KEEP
THEM VFR UNTIL THU EVENING WHEN LOW CLOUDS COULD COME IN THEN. IWD
WILL STAY LIFR THROUGH THE PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 332 PM EST WED DEC 10 2014
LIGHT WINDS UNDER A SURFACE HI PRES RIDGE WILL BECOME NW AND
INCREASE UP TO 20-25 KTS ON THU AND THU NIGHT AS A HI CENTER
STRENGTHENS IN THE MID MISSISSIPPI RIVER VALLEY. AS THIS HI SHIFTS
TO THE E THRU THE WEEKEND...THIS FLOW WILL BACK TO THE SW BUT REMAIN
RELATIVELY LIGHT WITH UNUSUALLY HI STABILITY OVER THE WATERS.
FOLLOWING THE PASSAGE OF A COLD FRONT ON MON...N WINDS WILL INCREASE
UP TO 25-30 KTS UNDER TIGHTENING PRES GRADIENT AHEAD OF HI PRES
MOVING INTO SCENTRAL CANADA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...07
MARINE...KC
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
259 AM CST Thu Dec 11 2014
...Cloudy Skies with Areas of Drizzle and Fog Expected Through the
Weekend...
.SHORT TERM...(Today and Tonight)
Issued at 236 AM CST THU DEC 11 2014
It is a cold and dreary morning across the Missouri Ozarks with
temperatures mainly in the middle 30s. The showers associated with
an exiting shortwave are still lingering mainly for areas along
and south of I-44 this morning. Have followed closely with the
Hi-Res short term models like the RUC and WRF with the evolution
of these scattered showers through 12z. Thinking is this will move
out of southern Missouri by 12z this morning. The remainder of the
area will continue to see patchy drizzle and light fog this morning.
Cloudy skies are here to stay for a while along with drizzle and
light fog from time to time through the end of the week.
Temperatures today will not budge much with highs only in the
lower to middle 40s expected today. Low clouds...areas of drizzle
and light fog can be expected once again this evening through
early Friday morning...especially for areas along and west of
Highway 65 and on top of the Ozark Plateau.
.LONG TERM...(Friday through Wednesday)
Issued at 236 AM CST THU DEC 11 2014
Friday will be a touch milder with highs in the lower 50s and
upper 50s to near 60 by Saturday. Like mentioned before...clouds
are here to stay through the weekend. The ground temperature will
be colder than the air temperature Friday night and again on
Saturday night with milder and moist air moving over that cold
ground. The SREF probabilities for fog development is higher for
those nights. There could be some localized dense fog potential
along with more drizzle. The forecast soundings show a completely
saturated air column from the ground up to 5k feet.
The potent storm system affecting the west coast of the country
the next day or so will be affecting our weather late Sunday into
Monday. A strong and vertically stacked low pressure system will
move across the south central Plains region Sunday night. This
will bring widespread rain and possibly isolated thunder to the
area late Sunday through Monday. No severe weather is expected
with this system. Average rainfall expected will be around an inch.
Showers or drizzle will lingering on the back side of the exiting
storm system Monday afternoon through Tuesday. Temperatures will
be knocked back down to more seasonable levels early and middle of
next week with a somewhat zonal flow expected in the upper levels.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1048 PM CST WED DEC 10 2014
Scattered showers continue across the forecast area this evening
and will continue with VCSH wording in initial hours of the 06z
TAF. Ceilings will continue to lower during the overnight with
low end MVFR into IFR conditions expected. While ceilings will
likely improve back into MVFR on Thursday, not expected to get
back to VFR through the period.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Lindenberg
AREA FORECAST DISCUSSION
NWS BILLINGS MT
300 AM MST THU DEC 11 2014
.SHORT TERM...VALID FOR TDY AND FRI...
DRY AND VERY WARM SOUTHWEST FLOW OF AIR WILL BE OVER THE REGION
TODAY TROUGH FRIDAY. THE ONLY WEATHER OF CONCERN WILL BE GUSTY
WINDS DEVELOPING IN THE GAP FLOW AREAS TODAY THROUGH FRIDAY. LEE-
SIDE SURFACE TROUGH DEVELOPING AS A DEEP UPPER TROUGH OF LOW
PRESSURE MOVES ONTO THE WEST COAST. THIS WILL BRING PERIODS OF
GUSTY WINDS TO LIVINGSTON AND NEAR NYE BUT THEY ARE EXPECTED TO
REMAIN BELOW ADVISORY CRITERIA. LOCAL GUIDANCE AND HRRR 80M WINDS
ALSO INDICATING WINDS TO REMAIN BELOW ADVISORY CRITERIA WITH THE
STRONGEST WINDS IN THE RANGE OF 40KTS. STRONG PUSH OF PACIFIC AIR
INTO THE AREA BOTH TODAY AND FRIDAY WITH 850 MB TEMPERATURES
PROGGED AT +14C TO +16C. THIS WILL BRING VERY MILD AFTERNOON
READINGS OF MID TO UPPER 50S ACROSS THE FORECAST AREA. WARMEST DAY
STILL LOOKS TO BE FRIDAY AS GOOD MIXING TAKING PLACE AHEAD OF A
PACIFIC COOL FRONT. TEMPERATURES SHOULD AGAIN REACH INTO THE 50S
TO LOWER 60S. THE ONLY FLY IN THE OINTMENT FOR FRIDAY HIGH
TEMPERATURES IS IF COOLER AIR BEGINS DRAINING OUT OF THE BIGHORN
BASIN AND DOWN THE CLARKS FORK VALLEY. BUFKIT SHOWING THIS A
POSSIBILITY SO ONLY TWEAKED TEMPERATURES SLIGHTLY FOR TOMORROW.
TROUGH APPROACHING THE AREA FRIDAY NIGHT AND WILL SPREAD LIGHT
RAIN AND SNOW SHOWERS INTO OUR WESTERN ZONES. MODELS STILL TAKING
STRONGEST FORCING SOUTH OF OUR AREA AND HAVE CONTINUED JUST
SCATTERED POPS FRIDAY NIGHT. RICHMOND
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MODELS HAVE BEEN CONSISTENT FROM RUN-TO-RUN OVER THE LAST DAY
WITH THE SYNOPTIC SCALE PATTERN THAT WILL AFFECT THE REGION DURING
THE EXTENDED PERIOD. ENSEMBLES DID NOTE SOME SPREAD IN THE
NORTHERN PORTION OF THE TROUGH THAT AFFECTS THE AREA THIS WEEKEND.
THERE WERE ALSO SOME DIFFERENCES IN THE FINER DETAILS OF THE
PATTERN BETWEEN THE MODELS.
PACIFIC TROUGH OFF THE W COAST THIS MORNING IN SATELLITE IMAGERY
WILL EVOLVE INTO A SPLITTING TROUGH AS IT APPROACHES THE REGION
ON SAT. THE WEAKER NORTHERN PART OF THE TROUGH WILL MOVE ACROSS
THE FORECAST AREA THROUGH SUN. THE GFS DEPICTS THIS FEATURE AS A
WEAK TROUGH...WHILE THE CANADIAN AND ECMWF SHOW A WEAK CUTOFF LOW
OVER SE ID/SW MT/W WY. THE MODELS DID AGREE IN THE EVOLUTION OF
THE SYSTEM/S MOISTURE AND COLD FRONTAL MOVEMENT THROUGH SAT NIGHT.
ON SUN...THE ECMWF WANTED TO HOLD ONTO MOISTURE OVER THE AREA
WHILE THE OTHER MODELS DRIED OUT THE AIRMASS. FOLLOWED THE
PREVIOUS FORECAST CLOSELY...GIVEN UNCERTAINTY IN THE
DETAILS...WITH LOW POPS OVERSPREADING THE PLAINS THROUGH SAT NIGHT
AND HIGHER POPS IN THE MOUNTAINS. BEGAN TO DRY OUT THE AREA ON
SUN.
ECMWF CONTINUED TO HOLD ONTO MOISTURE AND ASSOCIATED QPF THROUGH
MON NIGHT...DESPITE AN UPPER RIDGE MOVING OVER THE AREA. KEPT THE
FORECAST MAINLY DRY MON AND MON NIGHT. DIFFERENCES CONTINUED
BETWEEN MODELS ON TUE WITH ECMWF MOVING THE UPPER RIDGE OUT FASTER
THAN THE GFS. WENT DRY TUE WITH LOW MOUNTAIN POPS TUE NIGHT.
ANOTHER SPLITTING TROUGH WAS FORECAST TO MOVE INTO THE AREA WED
THROUGH THU. MOISTURE LOOKED GENERALLY CONFINED TO THE MOUNTAINS.
THE ECMWF BEGAN TO RUN COLDER THAN THE GFS BEGINNING ON MON...SO
WENT WITH A COMPROMISE FOR TEMPERATURES. SAT WILL BE WARM BEFORE
THE FRONT CROSSES THE AREA...WITH HIGHS IN THE LOWER 50S. EXPECT
HIGHS TO RUN IN THE 30S TO AROUND 40 DEGREES FOR THE REST OF THE
PERIOD. ARTHUR
&&
.AVIATION...
EXPECT LLWS OVER KBIL EARLY THIS MORNING AND AGAIN TONIGHT. OVER
KLVM...EXPECT LLWS TONIGHT. OTHERWISE...VFR WILL PREVAIL OVER THE
AREA TODAY THROUGH TONIGHT. ARTHUR
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 058 040/058 037/050 030/040 023/039 023/039 022/039
0/U 00/N 02/W 32/W 11/B 11/B 11/B
LVM 061 045/061 038/050 026/040 020/040 020/040 022/040
0/N 00/N 23/W 22/J 11/B 11/B 11/B
HDN 058 029/060 029/052 027/041 019/040 018/040 016/038
0/U 00/B 02/W 32/J 21/B 01/B 11/B
MLS 053 028/054 031/050 030/037 022/037 021/036 016/034
0/U 00/B 01/B 22/J 11/B 00/B 11/B
4BQ 059 029/060 033/054 029/039 021/039 023/039 016/037
0/U 00/B 01/B 22/W 21/B 11/B 11/B
BHK 056 032/057 032/051 027/036 020/036 020/033 014/031
0/U 00/U 00/B 22/J 22/J 00/B 01/B
SHR 061 030/063 031/052 026/038 018/039 018/038 016/038
0/U 00/B 02/W 33/J 21/B 11/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
350 AM CST THU DEC 11 2014
.SYNOPSIS...
ISSUED AT 350 AM CST THU DEC 11 2014
H5 ANALYSIS TONIGHT HAS AN AREA OF LOW PRESSURE CENTERED OVER NEW
YORK CITY WITH A TROUGH EXTENDING SWD INTO THE WESTERN ATLANTIC.
FURTHER WEST...A POSITIVELY TILTED RIDGE EXTENDED FROM THE FOUR
CORNERS INTO WESTERN ONTARIO. WEST OF THE RIDGE...A TROUGH OF LOW
PRESSURE EXTENDED FROM THE GULF OF ALASKA SWD INTO THE EASTERN
PACIFIC. CURRENT WV IMAGERY...HAS A DECENT PLUME OF MOISTURE
EXTENDING FROM CALIFORNIA...NWD INTO WESTERN MONTANA AND THE
PRAIRIE PROVINCES OF CANADA. A SECONDARY MOISTURE TAP EXTENDED
ACROSS MEXICO INTO THE GULF OF MEXICO AND THE GULF COAST STATES.
ACROSS SOUTH DAKOTA AND NEBRASKA...DRY AIR ALOFT WAS NOTED. AT
THE SURFACE...HIGH PRESSURE REMAINED ANCHORED ACROSS THE UPPER
MIDWEST...WHILE A WEAK SURFACE TROUGH EXTENDED FROM SERN MT INTO
EASTERN WYOMING AND NERN COLORADO. LIGHT SRLY WINDS WERE PRESENT
ACROSS THE PLAINS STATES WITH LOW LEVEL MOISTURE FLOWING NORTH
INTO CENTRAL AND EASTERN NEBRASKA TONIGHT. LOW LEVEL CLOUDS AND
DENSE FOG WERE PRESENT EAST OF A LINE FROM HAYES CENTER...TO
TRYON...TO BASSETT AND NAPER. VISBYS ACROSS PORTIONS OF CENTRAL
AND SOUTHWESTERN NEBRASKA HAVE DROPPED TO UNDER A HALF A MILE
OVERNIGHT AND A DENSE FOG ADVISORY WAS IN EFFECT FOR LOCATIONS
EAST AND SOUTH OF A LINE FROM HAYES CENTER...TO SUTHERLAND...TO
DUNNING AND TAYLOR. TEMPERATURES VARIED WIDELY TONIGHT WITH
READINGS AROUND 20 IN THE EASTERN PANHANDLE...TO THE MIDDLE 30S
IN THE NORTHEASTERN FORECAST AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST THU DEC 11 2014
IN THE SHORT TERM...FOG THIS MORNING AND TONIGHT...AND ITS
IMPACTS ON HIGHS TODAY AND LOWS TONIGHT WILL BE THE MAIN
FORECASTING CONCERNS. FOR THIS MORNING...LIGHT SRLY WINDS AND A
SERIOUS LACK OF MIXING...WILL LENGTHEN THE DURATION OF FOG THIS
MORNING. A GLANCE AT THE HRRR AND NAM 12 VISBY PRODUCTS...HAVE
THIS BURNING OFF DURING THE 16Z TO 18Z TIME FRAME. FOR LOCATIONS
GENERALLY ALONG AND WEST OF A LINE FROM CURTIS...TO NORTH
PLATTE...TO BASSETT...HIGHS ARE EXPECTED TO REACH THE 50S TO
AROUND 60 IN THE PANHANDLE. FURTHER EAST HOWEVER...STRATUS WILL
PERSIST INTO THE EARLY AFTERNOON HOURS...WHICH WILL HOLD TEMPS
BACK INTO THE 40S. FORTUNATELY...WITH THE VERY DRY AIR ALOFT AND
AN EXPECTED LACK OF HIGH LEVEL CLOUDINESS TODAY...THINKING HERE
IS THAT THE FOG/STRATUS SHOULD BURN OFF FROM WEST TO EAST TDY.
ALBEIT...LATER IN THE EAST...THUS THE COOLER TEMPS. FOR
TONIGHT...BL CONDITIONS WILL MOISTEN QUICKLY AFTER SUNSET AND
WITH INCREASED BL MOISTURE PUSHING NORTH INTO CENTRAL AND EASTERN
PORTIONS OF THE FORECAST AREA OVERNIGHT...FOG POTENTIAL IS VERY
HIGH ONCE AGAIN. THE LATEST NAM BL RH PROGS AND VISBY PRODUCT IS
INDICATING A HIGH POTENTIAL FOR FOG/STRATUS DEVELOPMENT EAST OF A
LINE FROM WAUNETA...TO MULLEN...TO SPRINGVIEW. WITH GOOD
CONFIDENCE AND LITTLE CHANGE IN THE SURFACE PATTERN...IE. SURFACE
HIGH TO THE EAST AND LIGHT SRLY WINDS...HAVE INSERTED AREAS OF
FOG TONIGHT ALONG AND EAST OF THE BEFORE MENTIONED LINE. IN
ADDITION...RAISED MIN TEMPS EAST OF THIS LINE...GIVEN THE
EXPECTED MOISTURE ADVECTION. WEST OF THE LINE...CLEAR
SKIES...WILL LEAD TO SEASONAL LOWS IN THE 20S IN THE PANHANDLE
AND NORTHWESTERN SANDHILLS. LIKE TONIGHT...ON THE WESTERN
PERIPHERY OF THE FOG FIELD...VISBYS MAY DROP DOWN TO A MILE OR
LESS AND A DENSE FOG ADVZY MAY BE NEEDED. WILL ADVISE THE
ONCOMING SHIFT OF THE POSSIBLE NEED FOR THIS WITH THE AFTERNOON
FCST PACKAGE. ONE FINAL NOTE WITH RESPECT TO DRIZZLE...LOOKED
CLOSELY AT FCST SOUNDINGS FOR TONIGHT...AND THE SATURATED LAYER
IS VERY SHALLOW AT AROUND 500 TO 700 FT THICK TONIGHT. COULDN/T
FIND ANY LIFT IN THIS MOIST LAYER...SO WILL LEAVE OUT A MENTION
OF DRIZZLE FOR THE TONIGHT PERIOD.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CST THU DEC 11 2014
MAIN CONCERN WILL BE THE EFFECTS OF INCREASING MOISTURE AHEAD OF
THE TROUGH FRIDAY INTO SATURDAY...THEN DETERMINING THE TRACK OF
THE LOW PRESSURE SYSTEM ACROSS THE SOUTHERN/CENTRAL PLAINS. ALSO
TIMING THE COOLER AIR SUNDAY INTO MONDAY BEHIND THE SYSTEM.
FRIDAY WILL SEE THE UPPER LEVEL LOW COME ON SHORE ACROSS THE PAC
COAST...MEANWHILE A RIDGE BUILDS ACROSS THE PLAINS. SURFACE HIGH
SETTLES OVER THE MISS RVR VALLEY. SOUTHERLY WINDS ON THE WEST
SIDE OF THE HIGH WILL TAP GULF MOISTURE AND BRING IT NORTHWARD.
THE RICH BL MOISTURE REMAINS...ALTHOUGH IT WILL STILL BE SHALLOW
FOR THE CWA ON FRIDAY. MORNING FOG WILL ERODE FROM THE
WEST...ALTHOUGH NOT EXPECTED A CLEARING DAY FOR ALL. THIS MAKES
FOR A TRICKY FORECAST AS CLOUDS WILL LIKELY LIMIT MIXING...AND
KEEP TEMPS DOWN. HIGHS IN THE 60S ACROSS THE WEST...WITH
50S...MAYBE SOME 40S IN THE EAST.
THE TROUGH WILL PUSH ACROSS THE DESERT SOUTHWEST SATURDAY. STILL
VERY WARM ALOFT...AND MORE MOISTURE ARRIVES WITH THE SOUTHERLY
WINDS. MOIST TRANSPORT VECTORS ARE FAVORABLE TO INCREASE THE
DEPTH OF THE BL MOISTURE. ALSO SEEING A LITTLE LIFT IN THE RICH
BL...AND WILL INCLUDE SOME DRIZZLE FRIDAY NIGHT INTO SATURDAY
MORNING. THE BLANKET OF CLOUDS WILL HELP TO KEEP TEMPS ABOVE
FREEZING...SO ONLY INCLUDE DZ IN THE FORECAST NOW. THE WARM
AIR/MOIST ADVECTION CONTINUES DURING THE DAY...AND EXPECT CLOUDS
TO REMAIN THROUGH THE DAY. THIS WILL LIMIT THE MIXING AND
FORECAST HIGHS ARE BELOW GUIDANCE...WHICH COULD STILL BE TOO WARM
PENDING HOW THE WAA OVERCOMES THE CLOUDS. ALSO BUFKIT SOUNDINGS
SUGGEST SOME BETTER /ALBEIT ONLY A LITTLE/ OMEGA AS THE DEPTH OF
THE MOISTURE LAYER INCREASE. COULD BE ENOUGH FOR A LITTLE HEAVIER
DRIZZLE AND WORDED THE FORECAST FOR LIGHT RAIN IN THE EAST.
BY SUNDAY THE SYSTEM WILL PUSH ACROSS TH ROCKIES AND LIFT ACROSS
THE PLAINS. STILL SOME TIMING/TRACK ISSUES...WITH THE LATEST
ROUND OF MODELS ALL TAKING THE TRACK A LITTLE FURTHER SOUTH FROM
EARLIER RUNS. STILL HAVE ENOUGH LL MOISTURE IN PLACE WHICH WILL
BE AIDED BY SOME WRAP AROUND MOISTURE/LIFT WHICH SHOULD PRODUCE
SOME LIGHT PRECIP. ALSO GOING TO SEE TEMPS FALLING AS COOLER AIR
GETS DRAW INTO THE SYSTEM. BEST LIFT IS ALONG THE SOUTHERN BORDER
AND TO THE SOUTH AND EAST...WHICH BRINGS CONCERN TO AMOUNT OF QPF
FOR THE CWA. IT LOOKS BETTER FOR AT LEAST SOME LIGHT
PRECIP...ALTHOUGH ONLY A SLIGHT SHIFT NORTHWARD COULD PLACE SOME
MORE SIGNIFICANT QPF FOR THE CWA. ALL IN ALL...STILL NOT VERY
CONFIDENT ON AMOUNT OF QPF FOR THE CWA. ALSO MODELS SLOWED THE
COLD AIR PUSH WHICH LESSENS CONFIDENCE ON TIMING THE CHANGE OVER
FROM RAIN TO SNOW SUNDAY INTO MONDAY.
LINGERING WRAP AROUND SNOW MONDAY NIGHT ACROSS N CENTRAL...THEN
WEAK RIDGING WILL HELP TO REDUCE CLOUDS FOR MID WEEK. THE ACTIVE
PATTERN CONTINUES WITH ANOTHER TROUGH DIGGING INTO THE DESERT
SOUTHWEST BY WEDNESDAY. EYES WILL BEGIN TO MONITOR THIS AS IT
CROSSES THE SOUTHERN/CENTRAL PLAINS TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1145 PM CST WED DEC 10 2014
LIFR CONDITIONS FORECAST AT KLBF UNTIL 16Z THURSDAY. CEILINGS AND
VISIBILITY SHOULD IMPROVE OR BECOME UNRESTRICTED BY 18Z. A
RETURNING SURGE OF MOISTURE WILL AGAIN BRING AT LEAST IFR
CONDITIONS BY 03Z/12TH. AT KVTN UNRESTRICTED CEILINGS AND VISIBILITY
FORECAST.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ037-038-
059-070-071.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...MASEK
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
344 AM CST THU DEC 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST THU DEC 11 2014
ALOFT: THE FLOW IS COMPLEX BUT ESSENTIALLY A RIDGE AXIS EXTENDED
FROM THE DESERT SW UP INTO THE CANADIAN PRAIRIES. THIS RIDGE WILL
SLOWLY CREEP TO THE E THRU TONIGHT WHILE REMAINING JUST W OF THE
FCST AREA. BY SUNRISE FRI...A POTENT SHORTWAVE TROF WILL BE MOVING
ONSHORE INTO SRN CA. THIS WILL BE PROVIDE THE BEST CHANCE FOR
MEANINGFUL PRECIP WE HAVE SEEN HERE SINCE LATE OCT. SEE BELOW FOR
THE DETAILS.
SURFACE: HIGH PRES WAS OVER THE UPPER MS VALLEY. IT WILL REMAIN
OVER THE MS VALLEY BUT GRADUALLY SINK S THRU TONIGHT.
NOW THRU SUNRISE: CLOUDY WITH SLOWLY DECREASING VSBYS...
ESPECIALLY ALONG AND W OF HWY 283. TEMPS HOLD STEADY IN THE LOW-
MID 30S.
FOG: BELIEVE VERIFYING THE FOG ADVISORY COULD BE SHAKY IN SOME
PLACES. DENSE FOG IS MOST LIKELY WITHIN 50 MILES ON EITHER SIDE OF
THE STRATUS EDGE. AREAS E OF HWY 183 ARE PROBABLY TOO FAR INTO THE
STRATUS AND BELIEVE VSBYS SHOULD BE NO WORSE THAN MVFR /3-5 MI/.
SO THE ERN ROW OF COUNTIES WAS TRIMMED OFF THE ADVISORY FROM
BUFFALO DOWN TO OSBORNE. THE ONLY COUNTIES I AM CONFIDENT IN
LEAVING DENSE FOG ARE DAWSON/GOSPER/FURNAS. PHELPS/HARLAN/
PHILLIPS/ROOKS ARE LOW CONFIDENCE. DID EXTEND THE ADVISORY THRU 10
AM AS IT IS VERY DIFFICULT TO GET RID OF FOG/DENSE FOG BEFORE LATE
AM THIS TIME OF YEAR.
TODAY: CLOUDY TO START WITH AREAS OF FOG W OF HWY 183 THRU
MIDDAY. EXPECT SOME SLOW IMPROVEMENT AND IT SHOULD BEGIN FROM THE
W WHERE THE STRATUS IS SHALLOWER. I HAVE THE ENTIRE FCST AREA
EVENTUALLY TURNING P/CLOUDY THIS AFTERNOON AND THIS COULD BE
OVERLY OPTIMISTIC...ESPECIALLY FOR PARTS OF THE AREA E OF HWY 281
WHERE THE STRATUS COULD LINGER THE ENTIRE DAY.
DESPITE THE WARM LOOK ALOFT...A SHALLOW COOL AIR MASS WAS IN
PLACE.
850 MB TEMPS WERE VERY WARM. IF NOT FOR THE SHALLOW COOL AIR MASS
AND STRATUS...TEMPS WOULD BE IN THE 60S TODAY. THE LOW-LVLS ARE
HIGHLY INVERTED /WARMER AIR ALOFT AND COLDER NEAR THE SFC/.
USED THE NAM LOW CLOUD PRODUCT FOR THE BASIS OF THE FCST WHICH
SUPPORTS FCSTR PATTERN RECOGNITION. HRRR LOW CLOUD PRODUCT IS ALSO
SUPPORTIVE.
HIGH TEMPS ARE LOW CONFIDENCE W OF HWY 183. WHILE MIXING WILL
INITIALLY BE SUPPRESSED...THE WRN EDGE OF THE STRATUS/FOG WILL BE
ERODED AND EXPECT THAT CLOUDS WILL BREAK-UP AND DECREASE FROM THE
W. AREAS W OF HWY 183 STAND THE BEST CHANCE FOR THE GREATEST
AMOUNT OF SUN TODAY. WHERE CLEARING OCCURS WILL PLAY A SUBSTANTIAL
ROLE IN HOW WARM TEMPS GET. WHILE IT`S NOT IN THE FCST...LOW 50S
WOULD BE POSSIBLE.
TONIGHT: ANY AREAS THAT ARE P/CLOUDY OR M/CLEAR WILL CLOUD BACK
OVER. HARD TO GET A HANDLE ON FOG POTENTIAL BECAUSE IT WILL HINGE
ON WHAT IS LEFT OF THE STRATUS AT SUNSET. FOR NOW PLAYED IT
SIMILAR TO THE PREVIOUS FCST WITH FOG DEVELOPING EARLY EVENING AND
EXPANDING. DRZL WAS WITHDRAWN FROM THE FCST AS MOISTURE JUST DOES
NOT APPEAR DEEP ENOUGH IN CROSS SECTIONS/SOUNDINGS.
LOW TEMPS WILL PROBABLY OCCUR WELL BEFORE MIDNIGHT...BEFORE FOG/
STRATUS OVERTAKE THE FCST AREA. ONCE THAT OCCURS...TEMPS SHOULD
FLAT-LINE OR EVEN SLOWLY CLIMB.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 344 AM CST THU DEC 11 2014
THIS SECTION WILL UPDATE SOON.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THU NIGHT)
ISSUED AT 1144 PM CST WED DEC 10 2014
REST OF TONIGHT: MVFR STRATUS CIGS WILL GRADUALLY DECAY TO IFR
AND EVENTUALLY LIFR. VSBYS ARE LOWER CERTAIN. SINCE STRATUS HAS
ALREADY INVADED AND ENVELOPED MUCH OF THE REGION...THE POTENTIAL
FOR IFR FOG LOOKS LOW. THIS IS SUPPORTED COMPARING THE CURRENT OBS
TO SIMILAR PAST SITUATIONS. FOR NOW MAINTAINED CONTINUITY WITH THE
PREVIOUS TAF ISSUANCE AT EAR WITH 1/4SM FG OVC002 BUT THIS MAY BE
TOO PESSIMISTIC. LIGHT S WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM
THU: LIFR STRATUS CIGS 300-500 FT AND MVFR VSBYS WILL GRADUALLY
IMPROVE AFTER 16Z...BUT IT WILL BE TOUGH TO GET RID OF THE
STRATUS. CURRENT LOW CLOUD GUIDANCE FROM THE 18Z NAM INDICATES
STRATUS SHOULD BREAK UP 20Z-22Z WITH A BRIEF PERIOD OF VFR
POSSIBLE LATE. S WINDS 10 KTS OR LESS. CONFIDENCE: MEDIUM
THU EVE: PROBABLY VFR TO START BUT CONDITIONS WILL BE FAVORABLE
FOR STRATUS TO REFORM WITH NO APPRECIABLE CHANGE IN THE WX
SITUATION. FCST GUIDANCE DOES NOT APPEAR TO BE HANDLING IT WELL
AND IS IN CONFLICT. NOT SURE IF THIS TURNS OUT A FOG OR A STRATUS
PROBLEM. THE MODIFIED RICHARDSON NUMBER SUGGESTS STRATUS BUT IT
WILL DEPEND ON HOW MUCH RADIATIONAL COOLING OCCURS JUST AFTER
SUNSET. CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ060-072-
073-082-083.
KS...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR KSZ005-017.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1201 AM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 1201 AM CST THU DEC 11 2014
MADE SOME RATHER SUBSTANTIAL CHANGES THRU SUNRISE. FCST TEMPS/
DWPTS WERE RUNNING SEVERAL DEGS BELOW REALITY. FCST GUIDANCE IS
NOT HANDLING THE SITUATION WELL EITHER. THE 4KM WRF-ARW IS THE
ONLY GUIDANCE SIMILAR TO WHAT I BELIEVE WILL HAPPEN. LOW CLOUDS
WILL KEEP TEMPS FROM GOING ANYWHERE. SO ESSENTIALLY ONLY LOWERED
TEMPS A COUPLE DEGS FROM CURRENT OBS. THIS RAISED LOW TEMPS 3-5F
MOST LOCATIONS.
UPDATE ISSUED AT 1144 PM CST WED DEC 10 2014
WE SOCKED IN WITH LOW STRATUS AND CIGS SHOULD CONT TO CASCADE
DOWNWARD THRU THE NIGHT. AS IS TYPICAL...VSBYS ARE LOWEST NEAR ITS
EDGE...W OF HWY 283. A DENSE FOG ADVISORY WAS ISSUED AT 934 PM AND
CONTS AS POSTED AND INCLUDES AREA ALONG AND/OR JUST W OF HWY 281.
THE MAIN CONCERN OVERNIGHT IS THE ERN ROW OF COUNTIES IN THE
ADVISORY /BUFFALO DOWN TO OSBORNE/. THESE COUNTIES MAY BE TOO FAR
AWAY FROM THE STRATUS EDGE FOR DENSE FOG. WE WILL RE-EVALUATE THIS
POTENTIAL LATER TONIGHT AND MAY NEED TO TRIM SOME COUNTIES.
THE FCST FOR THU INTO THU NIGHT WILL BE FOCUSED ON STRATUS/FOG
POTENTIAL. IT WILL BE SLOW...BUT WE SHOULD EVENTUALLY LOSE MOST OF
THE STRATUS THU AFTERNOON. BUT WITH IT REMAINING CLOSE BY AND
SUPPRESSED TEMP/DWPT SPREADS LIKELY TODAY...EXPECT IT TO MOVE BACK
IN AND/OR REFORM TONIGHT.
SO WE WILL BE PLAYING THE SKY COVER FAIRLY PESSIMISTIC THRU
TONIGHT.
&&
.SHORT TERM... (THIS EVENING THROUGH THURSDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THE PRIMARY FORECAST CONCERN WILL CENTER AROUND THE PROBABILITY OF
DENSE FOG AS EARLY AS THIS EVENING AND POSSIBLY PERSISTING UNTIL MID
MORNING ON THURSDAY. THERE IS THEN CONCERN AS TOO HOW QUICKLY THE
FOG AND LOW CLOUDS WILL SCATTER OUT OR IF WE WILL EVEN SEE ANY
SUNSHINE...WHICH HAS SIGNIFICANT IMPLICATIONS ON OUR THURSDAY HIGH
TEMPERATURE FORECAST.
TONIGHT...THE HRRR AND SREF BOTH INDICATE A MODEST CHANCE OF DENSE
FOG DEVELOPMENT WEST OF INTERSTATE 80 BEGINNING THIS EVENING.
CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE A DENSE FOG ADVISORY AT THIS
TIME...BUT WOULD CERTAINLY NOT BE SURPRISED IF AT LEAST SOME LOCAL
AREAS SEE DENSE FOG TONIGHT GIVEN THE HIGH LOW LEVEL RELATIVE
HUMIDITY. THE CLOUD CEILINGS SHOULD START TO LOWER AND THE FOG
DEVELOP ONCE WE SEE DIURNAL COOLING OF THE NEAR SFC LAYER THIS
EVENING. LOW LEVEL CLOUDS AND FOG WILL KEEP TEMPERATURES UP
SOME...AND WILL BE GOING ABOVE MODEL GUIDANCE...BUT STILL BELOW
FREEZING. THEREFORE...EXPECT SOME OF THAT FROZEN FOG AGAIN TONIGHT
ACROSS THE AREA RESULTING IN MORE WHITE TREES AND PERHAPS A FEW
SLICK SPOTS ON ELEVATED SURFACES.
THURSDAY...THE FOG WILL EVENTUALLY LIFT/BURN OFF...BUT THERE IS LESS
CERTAINTY AS TO HOW QUICKLY THE FOG WILL LIFT AND IF THE CLOUDS WILL
EVEN BE ABLE TO BURN OFF ACROSS THE ENTIRE AREA. IN FACT...AM GOING
TO GO MORE PESSIMISTIC WITH FORECAST HIGHS ON THURSDAY GIVEN
INCREASING BELIEF THAT LOW CLOUDS WILL HOLD THROUGH MUCH OF THE DAY
IF NOT ALL OF THE DAY FOR MANY LOCATIONS. EVEN IF THE LOW CLOUDS
BREAK UP SOME BY AFTERNOON...THERE WILL BE LITTLE TIME FOR MUCH
WARMING TO OCCUR. THE NAM MODEL HAS BEEN RATHER CONSISTENT WITH HIGH
RH VALUES INDICATIVE OF A LOW CLOUD DECK FROM AROUND 900 MB TO THE
SFC. THE CLOUD DECK SHOULD NOT BE THICK ENOUGH TO PRODUCE
DRIZZLE...BUT WILL IMPACT HIGHS. THEREFORE...WILL NOW BE CALLING FOR
FORECAST HIGHS IN THE LOWER 40S EAST OF HWY 281 TO THE MID AND UPPER
40S WEST OF HIGHWAY 281...WHICH IS A GOOD DEAL COOLER THAN WE HAD IN
THE FORECAST A FEW DAYS AGO.
.MID TERM...(THURSDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THIS 48-HOUR PERIOD IS EFFECTIVELY THE "RELATIVE CALM" BEFORE THE
POTENTIALLY MORE IMPACTFUL SUNDAY-MONDAY STORM SYSTEM DESCRIBED IN
THE LONG-TERM SECTION BELOW. EVEN SO...THIS IS LOOKING LIKE A
LARGELY DREARY...AND AT TIMES FOGGY/DRIZZLY PERIOD...AND THE ODDS OF
SEEING MUCH SUNSHINE ON FRIDAY AND SATURDAY ARE LOOKING PRETTY SLIM.
DESPITE THE OVERALL-GLOOMY WEATHER PATTERN...AT LEAST TEMPERATURES
WILL BE ON THE SEASONABLY MILD SIDE...WITH HIGHS FRI/SAT CURRENTLY
AIMED INTO THE 50S...AND LOWS FRIDAY NIGHT HOLDING UP INTO THE 40S
MOST AREAS...POTENTIALLY SETTING RECORD WARM LOW TEMPS FOR DEC. 13TH
AT OUR PRIMARY CLIMATE RECORD SITES GRAND ISLAND/HASTINGS. DESPITE
THE MILDER READINGS...THIS FORECAST CONTINUES THE TREND FROM
PREVIOUS ISSUANCES OF SHAVING ANOTHER 2-3 DEGREES OFF HIGHS
FRIDAY/SATURDAY...AND AS EVIDENCED BY WHAT HAPPENED JUST TODAY...ITS
QUITE POSSIBLE THAT FURTHER DOWNWARD ADJUSTMENTS MAY BE NEEDED IF
AREAS REMAIN SOCKED IN UNDER LOW STRATUS.
IN TERMS OF WEATHER HAZARDS...FORTUNATELY ANY DRIZZLE/LIGHT RAIN
THAT FALLS DURING THIS TIME FRAME SHOULD BE OF THE NON-FREEZING
VARIETY. THAT LEAVES NIGHT-TIME/MORNING FOG AS THE PARAMOUNT
CONCERN...AND WHETHER OR NOT IT BECOMES DENSE (VISIBILITY 1/4 MILE
OR LESS). ALTHOUGH THERE ARE SUGGESTIONS IN NAM/SREF VISIBILITY
PROGS THAT DENSE FOG IS A POSSIBILITY BOTH NIGHTS IN AT LEAST PARTS
OF THE CWA...ITS JUST TOO SOON TO PINPOINT WITH ANY CONFIDENCE...SO
WILL CALL FOR GENERIC "PATCHY" OR "AREAS" OF FOG AT THIS TIME AND
MENTION IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID) THAT VISIBILITY
REDUCTIONS TO LESS THAN 1 MILE ARE POSSIBLE (IF NOT PROBABLE).
GETTING INTO MORE DETAIL NOW IN 12-HOUR BLOCKS...
THURSDAY EVENING/NIGHT...THE BIG MID-UPPER LEVEL PICTURE FEATURES A
SEEMINGLY "QUIET" PATTERN WITH THE CENTRAL PLAINS DOMINATED BY A
LARGE SCALE RIDGE. HOWEVER...THERE IS MORE GOING ON DOWN CLOSER TO
THE SURFACE. MADE LITTLE CHANGE FROM PREVIOUS FORECAST HERE...AS
HAVE MAINTAINED EITHER A PATCHY OR AREAS OF FOG MENTION THROUGHOUT
THE NIGHT...AS MOIST SOUTHERLY FLOW PERSISTS. THE PRESENCE OF LIGHT-
BUT-STEADY 5-10 MPH BREEZES COULD WORK AGAINST WIDESPREAD DENSE FOG
ISSUES...BUT THAT IS YET TO BE SEEN. AS FOR DRIZZLE POTENTIAL...IT
IS LOOKING A BIT LESS FAVORABLE THAN IT DID 24 HOURS AGO DUE TO THE
DEPTH OF SATURATION TOPPING OUT CLOSER TO ONE-HALF KILOMETER (KM)
THAN 1 KM IN THE LATEST NAM FORECAST SOUNDINGS...BUT WAS UNWILLING
TO YANK IT FROM THE FORECAST YET AND WILL LET NEXT FEW SHIFTS TAKE
ANOTHER LOOK. DID HOWEVER "DOWNGRADE" THE PROBABILITY OF DRIZZLE
FROM CHANCE TO SLIGHT CHANCE...AND KEPT IT IN KS ZONES ONLY PRE-
MIDNIGHT...BEFORE EXPANDING IT NORTHWARD ACROSS THE MAJORITY OF NEB
ZONES POST-MIDNIGHT. ALL IN ALL THOUGH...FOG SHOULD BE MORE
PREVALENT THAN DRIZZLE. MADE LITTLE CHANGE TO LOW TEMPS...KEEPING
MOST OF THE CWA UP INTO THE MID- UPPER 30S...EXCEPT FOR COLDER
READINGS CLOSER TO 30 IN FAR NORTHERN/WESTERN COUNTIES.
FRIDAY DAYTIME...THE HEART OF THE MID-UPPER LEVEL RIDGE AXIS
TRANSITIONS OVER THE LOCAL AREA...BUT DOWN LOW THE STORY REMAINS
MUCH THE SAME. LEANING TOWARD THE 12Z NAM DEPICTION MORE THAN
ANYTHING...WIDESPREAD LOW STRATUS CLOUDS SHOULD CONTINUE TO
ENCOMPASS MOST IF NOT ALL OF THE CWA...AND EVEN THOUGH SKY COVER WAS
INCREASED IT COULD PROBABLY TREND HIGHER. OF COURSE...BRIEF POCKETS
OF SUNSHINE CANNOT BE COMPLETELY RULED OUT EITHER. SOUTHERLY BREEZES
GENERALLY 10-15 MPH WILL PREVAIL THROUGH THE DAY. AS FOR FOG/DRIZZLE
POTENTIAL...CONTINUED BOTH OF THESE ELEMENTS INTO THE FRIDAY MORNING
HOURS OUT OF THURSDAY NIGHT...BUT BASED ON THE LACK OF "SPLOTCHY
QPF" INDICATED BY THE 12Z NAM DURING THE AFTERNOON HOURS HAVE OPTED
TO KEEP FRIDAY AFTERNOON DRIZZLE/FOG FREE AT LEAST FOR NOW. AS
MENTIONED ABOVE...MADE MINOR DOWNWARD TWEAKS TO HIGH TEMPS...BUT
STILL AIMING FROM LOW 50S NORTHEAST TO MAINLY MID 50S SOUTHWEST.
FRIDAY NIGHT...BY THIS TIME THE LARGE SCALE RIDGE AXIS IS STARTING
TO DEPART EAST OF THE AREA...BUT THE LARGE/AMPLIFIED WESTERN TROUGH
STILL REMAINS WELL-WEST...WITH THE BASE OF THIS TROUGH ONLY REACHING
THE SOUTHERN CA/AZ BORDER AREA BY SUNRISE SATURDAY. NEAR/AT THE
SURFACE...THE SAME MOIST/WIDESPREAD CLOUDY AIRMASS CONTINUES...AND
BY THIS TIME MOISTURE DEPTH SHOULD BE INCREASING ENOUGH TO MAKE
DRIZZLE MORE LIKELY AND HAVE GONE WITH "CHANCE" WORDING HERE INSTEAD
OF JUST SLIGHT CHANCE AS THE NIGHT BEFORE. ALSO BLANKETED THE ENTIRE
CWA WITH AREAS OF FOG POTENTIAL. ASSUMING THAT TEMPS DURING THE
PRECEDING DAY WARM AS MUCH AS PROGGED...THERE SHOULD BE VERY LITTLE
DROP-OFF FRIDAY NIGHT...AND HAVE QUITE-MILD LOWS AIMED INTO THE LOW-
MID 40S MOST AREAS.
SATURDAY DAYTIME...IN SOME WAYS THIS RESEMBLES A SOMEWHAT
MILD/"HUMID" EARLY SPRING DAY...AS SURFACE DEWPOINTS ARE CURRENTLY
AIMED TO RISE WELL INTO THE MID-UPPER 40S AND POTENTIALLY EVEN LOW
50S IN SOME PLACES. ALTHOUGH THE MAIN VORT MAX WITHIN THE EXPANSIVE
WESTERN CONUS LOW CONTINUES TO SLOWLY APPROACH...CURRENT
NAM/GFS/ECMWF RUNS ONLY BRING IT TO NEAR THE 4-CORNERS AREA BY DAYS
END...WITH LITTLE IF ANY LARGE-SCALE FORCING INFLUENCING THE CENTRAL
PLAINS YET. THIS MEANS THAT ANY PRECIP CHANCES WILL CONTINUE TO BE
DRIVEN BY SHALLOW PROCESSES WITHIN THE LAYER STRATUS DECK. COMPARED
TO THE PREVIOUS 24-36 HOURS...SATURDAY DAYTIME APPEARS TO HAVE THE
BEST POTENTIAL FOR A MORE WIDESPREAD/POTENTIALLY EVEN MEASURABLE
DRIZZLE/LIGHT RAIN ACROSS MUCH OF THE AREA...AND THUS OPTED TO
CONTINUE AN OFFICIAL 20 PERCENT MEASURABLE POP IN THIS PERIOD. AS
WITH FRIDAY...SHAVED A FEW DEGREES OFF HIGHS AND MAYBE NOT QUITE
ENOUGH...BUT NOW HAVE MID-UPPER 50S ACROSS THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THE START OF THE LONG TERM PERIOD...00Z SUNDAY...HAS NOT SEEN ANY
SIGNIFICANT CHANGES IN THE MODELS...WITH A WELL AMPLIFIED PATTERN IN
PLACE ACROSS THE CONUS...AS RIDGING EXTENDS FROM ERN TX NORTH INTO
ONTARIO...WHILE TROUGHING DIGS SOUTH THROUGH THE ROCKIES. THE MAIN
UPPER LEVEL LOW PRESSURE SYSTEM WHICH WILL BEAR WATCHING IN THE
COMING DAYS IS EXPECTED TO BE IN PLACE OVER THE FOUR CORNERS REGION.
AT THE SURFACE...LOW PRESSURE REMAINS IN PLACE OVER ERN PORTIONS OF
CO...WITH A TROUGH AXIS EXTENDING N/NE INTO THE DAKOTAS...KEEPING
THE SOUTHERLY WINDS GOING ACROSS THE CWA. THE STREAM OF INCREASED
WARM AIR/MOISTURE ADVECTION NORTH INTO THE AREA...KEEPING PLENTY OF
LOW LEVEL CLOUD COVER AROUND...ALONG WITH THE CONTINUED POTENTIAL
DRIZZLE/LIGHT RAIN. OVERNIGHT LOWS SAT NIGHT/SUN MORNING WILL BE
MILD WITH 40S AND A FEW 50S CURRENTLY FORECAST.
SUNDAY AND MONDAY CERTAINLY THE MOST INTERESTING TIME TIME FRAME OF
THE PERIOD...AS WE SEE THE ARRIVAL OF THAT UPPER LEVEL LOW PRESSURE
SYSTEM...AND THE POTENTIAL FOR ACCUMULATING SNOWFALL. DURING THE
DAYTIME HOURS ON SUNDAY...THE LOW IS EXPECTED TO EMERGE OUT OF THE
ROCKIES AND ONTO THE PLAINS...ENDING UP BY 00Z MONDAY ROUGHLY OVER
THE OK/TX PANHANDLE AREA. HOW IT EVOLVES BEYOND THAT AND WHERE ITS
ULTIMATE TRACK ENDS UP WILL DRIVE WHAT OUR CWA SEES SUNDAY NIGHT
THROUGH MONDAY /PERHAPS LINGERING INTO MONDAY NIGHT?/.
PLENTY OF UNCERTAINTY REMAINS WITH THIS SYSTEM. PREVIOUS MODEL RUNS
HAD GENERALLY TAKEN THE SYSTEM ALONG A MORE SOUTHERLY PATH...LEAVING
OUR CWA MORE ON THE NRN EDGE OF THE MAIN ACTIVITY. LOOKING AT THE
12Z RUN OF MODELS TODAY...THE GFS/GEM HAVE A MORE NRN TRACK THROUGH
MONDAY MORNING...TAKING THE 500 AND ESP 700MB LOWS ACROSS CENTRAL
KS...IF NOT RIGHT OVER OUR SRN CWA...AND USHERS IN COLDER
AIR/TRANSITION TO SNOW EVERYWHERE QUICKER. THE LATEST RUN OF THE
ECMWF HOWEVER KEEPS THE TRACK MORE OVER NRN OK...AND IS A TOUCH
SLOWER WITH THE COLDER AIR. THE START OF THIS EVENT IS STILL 4 DAYS
OUT...SO PLENTY EARLY TO BE BUYING FULL IN TO ANY PARTICULAR MODEL
OR MODEL RUN...AS 24 HRS FROM NOW THEY MAY LOOK DIFFERENT.
HOWEVER...EITHER SOLUTION WOULD RESULT IN ACCUMULATING SNOWFALL FOR
THE CWA...DIFFERENCE IS IN WHERE THE HEAVIER /SEVERAL INCHES
POTENTIALLY/ COULD END UP. COMBINED WITH THE EXPECTED GUSTY
NORTHWEST WINDS BUILDING IN BEHIND A PASSING COLD...THOSE WITH
TRAVEL PLANS DURING THIS PERIOD REALLY NEED TO KEEP A CLOSE EYE ON
THE FORECAST IN THE COMING DAYS...LOT OF DETAILS YET TO BE IRONED
OUT. AS FAR AS HIGH TEMPERATURES GO...ON SUNDAY AHEAD OF THE FRONTAL
PASSAGE...HIGHS IN THE MID 40S TO MID 50S ARE CURRENTLY IN THE
FORECAST...WITH LOWER/MID 30S GOING FOR MONDAY.
DRY CONDITIONS RETURN TO THE FORECAST FOR TUESDAY AND WEDNESDAY...AS
UPPER LEVEL SHORTWAVE RIDGING BUILDS IN BEHIND THIS STORM SYSTEM.
CONFIDENCE IN TEMPS IS NOT HIGH....NOT EXPECTING A NOTABLE CHANGE IN
THE OVERALL AIR MASS...BUT SNOWFALL ON THE GROUND WOULD COMPLICATE
THINGS. CURRENT FORECAST HIGHS BOTH DAYS REMAIN IN THE 30S.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1144 PM CST WED DEC 10 2014
REST OF TONIGHT: MVFR STRATUS CIGS WILL GRADUALLY DECAY TO IFR
AND EVENTUALLY LIFR. VSBYS ARE LOWER CERTAIN. SINCE STRATUS HAS
ALREADY INVADED AND ENVELOPED MUCH OF THE REGION...THE POTENTIAL
FOR IFR FOG LOOKS LOW. THIS IS SUPPORTED COMPARING THE CURRENT OBS
TO SIMILAR PAST SITUATIONS. FOR NOW MAINTAINED CONTINUITY WITH THE
PREVIOUS TAF ISSUANCE AT EAR WITH 1/4SM FG OVC002 BUT THIS MAY BE
TOO PESSIMISTIC. LIGHT S WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM
THU: LIFR STRATUS CIGS 300-500 FT AND MVFR VSBYS WILL GRADUALLY
IMPROVE AFTER 16Z...BUT IT WILL BE TOUGH TO GET RID OF THE
STRATUS. CURRENT LOW CLOUD GUIDANCE FROM THE 18Z NAM INDICATES
STRATUS SHOULD BREAK UP 20Z-22Z WITH A BRIEF PERIOD OF VFR
POSSIBLE LATE. S WINDS 10 KTS OR LESS. CONFIDENCE: MEDIUM
THU EVE: PROBABLY VFR TO START BUT CONDITIONS WILL BE FAVORABLE
FOR STRATUS TO REFORM WITH NO APPRECIABLE CHANGE IN THE WX
SITUATION. FCST GUIDANCE DOES NOT APPEAR TO BE HANDLING IT WELL
AND IS IN CONFLICT. NOT SURE IF THIS TURNS OUT A FOG OR A STRATUS
PROBLEM. THE MODIFIED RICHARDSON NUMBER SUGGESTS STRATUS BUT IT
WILL DEPEND ON HOW MUCH RADIATIONAL COOLING OCCURS JUST AFTER
SUNSET. CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR NEZ060-061-
072>074-082>084.
KS...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR KSZ005-006-017-
018.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...WESELY
LONG TERM...ADP
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1144 PM CST WED DEC 10 2014
.UPDATE...
ISSUED AT 1144 PM CST WED DEC 10 2014
WE SOCKED IN WITH LOW STRATUS AND CIGS SHOULD CONT TO CASCADE
DOWNWARD THRU THE NIGHT. AS IS TYPICAL...VSBYS ARE LOWEST NEAR ITS
EDGE...W OF HWY 283. A DENSE FOG ADVISORY WAS ISSUED AT 934 PM AND
CONTS AS POSTED AND INCLUDES AREA ALONG AND/OR JUST W OF HWY 281.
THE MAIN CONCERN OVERNIGHT IS THE ERN ROW OF COUNTIES IN THE
ADVISORY /BUFFALO DOWN TO OSBORNE/. THESE COUNTIES MAY BE TOO FAR
AWAY FROM THE STRATUS EDGE FOR DENSE FOG. WE WILL RE-EVALUATE THIS
POTENTIAL LATER TONIGHT AND MAY NEED TO TRIM SOME COUNTIES.
THE FCST FOR THU INTO THU NIGHT WILL BE FOCUSED ON STRATUS/FOG
POTENTIAL. IT WILL BE SLOW...BUT WE SHOULD EVENTUALLY LOSE MOST OF
THE STRATUS THU AFTERNOON. BUT WITH IT REMAINING CLOSE BY AND
SUPPRESSED TEMP/DWPT SPREADS LIKELY TODAY...EXPECT IT TO MOVE BACK
IN AND/OR REFORM TONIGHT.
SO WE WILL BE PLAYING THE SKY COVER FAIRLY PESSIMISTIC THRU
TONIGHT.
&&
.SHORT TERM... (THIS EVENING THROUGH THURSDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THE PRIMARY FORECAST CONCERN WILL CENTER AROUND THE PROBABILITY OF
DENSE FOG AS EARLY AS THIS EVENING AND POSSIBLY PERSISTING UNTIL MID
MORNING ON THURSDAY. THERE IS THEN CONCERN AS TOO HOW QUICKLY THE
FOG AND LOW CLOUDS WILL SCATTER OUT OR IF WE WILL EVEN SEE ANY
SUNSHINE...WHICH HAS SIGNIFICANT IMPLICATIONS ON OUR THURSDAY HIGH
TEMPERATURE FORECAST.
TONIGHT...THE HRRR AND SREF BOTH INDICATE A MODEST CHANCE OF DENSE
FOG DEVELOPMENT WEST OF INTERSTATE 80 BEGINNING THIS EVENING.
CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE A DENSE FOG ADVISORY AT THIS
TIME...BUT WOULD CERTAINLY NOT BE SURPRISED IF AT LEAST SOME LOCAL
AREAS SEE DENSE FOG TONIGHT GIVEN THE HIGH LOW LEVEL RELATIVE
HUMIDITY. THE CLOUD CEILINGS SHOULD START TO LOWER AND THE FOG
DEVELOP ONCE WE SEE DIURNAL COOLING OF THE NEAR SFC LAYER THIS
EVENING. LOW LEVEL CLOUDS AND FOG WILL KEEP TEMPERATURES UP
SOME...AND WILL BE GOING ABOVE MODEL GUIDANCE...BUT STILL BELOW
FREEZING. THEREFORE...EXPECT SOME OF THAT FROZEN FOG AGAIN TONIGHT
ACROSS THE AREA RESULTING IN MORE WHITE TREES AND PERHAPS A FEW
SLICK SPOTS ON ELEVATED SURFACES.
THURSDAY...THE FOG WILL EVENTUALLY LIFT/BURN OFF...BUT THERE IS LESS
CERTAINTY AS TO HOW QUICKLY THE FOG WILL LIFT AND IF THE CLOUDS WILL
EVEN BE ABLE TO BURN OFF ACROSS THE ENTIRE AREA. IN FACT...AM GOING
TO GO MORE PESSIMISTIC WITH FORECAST HIGHS ON THURSDAY GIVEN
INCREASING BELIEF THAT LOW CLOUDS WILL HOLD THROUGH MUCH OF THE DAY
IF NOT ALL OF THE DAY FOR MANY LOCATIONS. EVEN IF THE LOW CLOUDS
BREAK UP SOME BY AFTERNOON...THERE WILL BE LITTLE TIME FOR MUCH
WARMING TO OCCUR. THE NAM MODEL HAS BEEN RATHER CONSISTENT WITH HIGH
RH VALUES INDICATIVE OF A LOW CLOUD DECK FROM AROUND 900 MB TO THE
SFC. THE CLOUD DECK SHOULD NOT BE THICK ENOUGH TO PRODUCE
DRIZZLE...BUT WILL IMPACT HIGHS. THEREFORE...WILL NOW BE CALLING FOR
FORECAST HIGHS IN THE LOWER 40S EAST OF HWY 281 TO THE MID AND UPPER
40S WEST OF HIGHWAY 281...WHICH IS A GOOD DEAL COOLER THAN WE HAD IN
THE FORECAST A FEW DAYS AGO.
.MID TERM...(THURSDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THIS 48-HOUR PERIOD IS EFFECTIVELY THE "RELATIVE CALM" BEFORE THE
POTENTIALLY MORE IMPACTFUL SUNDAY-MONDAY STORM SYSTEM DESCRIBED IN
THE LONG-TERM SECTION BELOW. EVEN SO...THIS IS LOOKING LIKE A
LARGELY DREARY...AND AT TIMES FOGGY/DRIZZLY PERIOD...AND THE ODDS OF
SEEING MUCH SUNSHINE ON FRIDAY AND SATURDAY ARE LOOKING PRETTY SLIM.
DESPITE THE OVERALL-GLOOMY WEATHER PATTERN...AT LEAST TEMPERATURES
WILL BE ON THE SEASONABLY MILD SIDE...WITH HIGHS FRI/SAT CURRENTLY
AIMED INTO THE 50S...AND LOWS FRIDAY NIGHT HOLDING UP INTO THE 40S
MOST AREAS...POTENTIALLY SETTING RECORD WARM LOW TEMPS FOR DEC. 13TH
AT OUR PRIMARY CLIMATE RECORD SITES GRAND ISLAND/HASTINGS. DESPITE
THE MILDER READINGS...THIS FORECAST CONTINUES THE TREND FROM
PREVIOUS ISSUANCES OF SHAVING ANOTHER 2-3 DEGREES OFF HIGHS
FRIDAY/SATURDAY...AND AS EVIDENCED BY WHAT HAPPENED JUST TODAY...ITS
QUITE POSSIBLE THAT FURTHER DOWNWARD ADJUSTMENTS MAY BE NEEDED IF
AREAS REMAIN SOCKED IN UNDER LOW STRATUS.
IN TERMS OF WEATHER HAZARDS...FORTUNATELY ANY DRIZZLE/LIGHT RAIN
THAT FALLS DURING THIS TIME FRAME SHOULD BE OF THE NON-FREEZING
VARIETY. THAT LEAVES NIGHT-TIME/MORNING FOG AS THE PARAMOUNT
CONCERN...AND WHETHER OR NOT IT BECOMES DENSE (VISIBILITY 1/4 MILE
OR LESS). ALTHOUGH THERE ARE SUGGESTIONS IN NAM/SREF VISIBILITY
PROGS THAT DENSE FOG IS A POSSIBILITY BOTH NIGHTS IN AT LEAST PARTS
OF THE CWA...ITS JUST TOO SOON TO PINPOINT WITH ANY CONFIDENCE...SO
WILL CALL FOR GENERIC "PATCHY" OR "AREAS" OF FOG AT THIS TIME AND
MENTION IN THE HAZARDOUS WEATHER OUTLOOK (HWOGID) THAT VISIBILITY
REDUCTIONS TO LESS THAN 1 MILE ARE POSSIBLE (IF NOT PROBABLE).
GETTING INTO MORE DETAIL NOW IN 12-HOUR BLOCKS...
THURSDAY EVENING/NIGHT...THE BIG MID-UPPER LEVEL PICTURE FEATURES A
SEEMINGLY "QUIET" PATTERN WITH THE CENTRAL PLAINS DOMINATED BY A
LARGE SCALE RIDGE. HOWEVER...THERE IS MORE GOING ON DOWN CLOSER TO
THE SURFACE. MADE LITTLE CHANGE FROM PREVIOUS FORECAST HERE...AS
HAVE MAINTAINED EITHER A PATCHY OR AREAS OF FOG MENTION THROUGHOUT
THE NIGHT...AS MOIST SOUTHERLY FLOW PERSISTS. THE PRESENCE OF LIGHT-
BUT-STEADY 5-10 MPH BREEZES COULD WORK AGAINST WIDESPREAD DENSE FOG
ISSUES...BUT THAT IS YET TO BE SEEN. AS FOR DRIZZLE POTENTIAL...IT
IS LOOKING A BIT LESS FAVORABLE THAN IT DID 24 HOURS AGO DUE TO THE
DEPTH OF SATURATION TOPPING OUT CLOSER TO ONE-HALF KILOMETER (KM)
THAN 1 KM IN THE LATEST NAM FORECAST SOUNDINGS...BUT WAS UNWILLING
TO YANK IT FROM THE FORECAST YET AND WILL LET NEXT FEW SHIFTS TAKE
ANOTHER LOOK. DID HOWEVER "DOWNGRADE" THE PROBABILITY OF DRIZZLE
FROM CHANCE TO SLIGHT CHANCE...AND KEPT IT IN KS ZONES ONLY PRE-
MIDNIGHT...BEFORE EXPANDING IT NORTHWARD ACROSS THE MAJORITY OF NEB
ZONES POST-MIDNIGHT. ALL IN ALL THOUGH...FOG SHOULD BE MORE
PREVALENT THAN DRIZZLE. MADE LITTLE CHANGE TO LOW TEMPS...KEEPING
MOST OF THE CWA UP INTO THE MID- UPPER 30S...EXCEPT FOR COLDER
READINGS CLOSER TO 30 IN FAR NORTHERN/WESTERN COUNTIES.
FRIDAY DAYTIME...THE HEART OF THE MID-UPPER LEVEL RIDGE AXIS
TRANSITIONS OVER THE LOCAL AREA...BUT DOWN LOW THE STORY REMAINS
MUCH THE SAME. LEANING TOWARD THE 12Z NAM DEPICTION MORE THAN
ANYTHING...WIDESPREAD LOW STRATUS CLOUDS SHOULD CONTINUE TO
ENCOMPASS MOST IF NOT ALL OF THE CWA...AND EVEN THOUGH SKY COVER WAS
INCREASED IT COULD PROBABLY TREND HIGHER. OF COURSE...BRIEF POCKETS
OF SUNSHINE CANNOT BE COMPLETELY RULED OUT EITHER. SOUTHERLY BREEZES
GENERALLY 10-15 MPH WILL PREVAIL THROUGH THE DAY. AS FOR FOG/DRIZZLE
POTENTIAL...CONTINUED BOTH OF THESE ELEMENTS INTO THE FRIDAY MORNING
HOURS OUT OF THURSDAY NIGHT...BUT BASED ON THE LACK OF "SPLOTCHY
QPF" INDICATED BY THE 12Z NAM DURING THE AFTERNOON HOURS HAVE OPTED
TO KEEP FRIDAY AFTERNOON DRIZZLE/FOG FREE AT LEAST FOR NOW. AS
MENTIONED ABOVE...MADE MINOR DOWNWARD TWEAKS TO HIGH TEMPS...BUT
STILL AIMING FROM LOW 50S NORTHEAST TO MAINLY MID 50S SOUTHWEST.
FRIDAY NIGHT...BY THIS TIME THE LARGE SCALE RIDGE AXIS IS STARTING
TO DEPART EAST OF THE AREA...BUT THE LARGE/AMPLIFIED WESTERN TROUGH
STILL REMAINS WELL-WEST...WITH THE BASE OF THIS TROUGH ONLY REACHING
THE SOUTHERN CA/AZ BORDER AREA BY SUNRISE SATURDAY. NEAR/AT THE
SURFACE...THE SAME MOIST/WIDESPREAD CLOUDY AIRMASS CONTINUES...AND
BY THIS TIME MOISTURE DEPTH SHOULD BE INCREASING ENOUGH TO MAKE
DRIZZLE MORE LIKELY AND HAVE GONE WITH "CHANCE" WORDING HERE INSTEAD
OF JUST SLIGHT CHANCE AS THE NIGHT BEFORE. ALSO BLANKETED THE ENTIRE
CWA WITH AREAS OF FOG POTENTIAL. ASSUMING THAT TEMPS DURING THE
PRECEDING DAY WARM AS MUCH AS PROGGED...THERE SHOULD BE VERY LITTLE
DROP-OFF FRIDAY NIGHT...AND HAVE QUITE-MILD LOWS AIMED INTO THE LOW-
MID 40S MOST AREAS.
SATURDAY DAYTIME...IN SOME WAYS THIS RESEMBLES A SOMEWHAT
MILD/"HUMID" EARLY SPRING DAY...AS SURFACE DEWPOINTS ARE CURRENTLY
AIMED TO RISE WELL INTO THE MID-UPPER 40S AND POTENTIALLY EVEN LOW
50S IN SOME PLACES. ALTHOUGH THE MAIN VORT MAX WITHIN THE EXPANSIVE
WESTERN CONUS LOW CONTINUES TO SLOWLY APPROACH...CURRENT
NAM/GFS/ECMWF RUNS ONLY BRING IT TO NEAR THE 4-CORNERS AREA BY DAYS
END...WITH LITTLE IF ANY LARGE-SCALE FORCING INFLUENCING THE CENTRAL
PLAINS YET. THIS MEANS THAT ANY PRECIP CHANCES WILL CONTINUE TO BE
DRIVEN BY SHALLOW PROCESSES WITHIN THE LAYER STRATUS DECK. COMPARED
TO THE PREVIOUS 24-36 HOURS...SATURDAY DAYTIME APPEARS TO HAVE THE
BEST POTENTIAL FOR A MORE WIDESPREAD/POTENTIALLY EVEN MEASURABLE
DRIZZLE/LIGHT RAIN ACROSS MUCH OF THE AREA...AND THUS OPTED TO
CONTINUE AN OFFICIAL 20 PERCENT MEASURABLE POP IN THIS PERIOD. AS
WITH FRIDAY...SHAVED A FEW DEGREES OFF HIGHS AND MAYBE NOT QUITE
ENOUGH...BUT NOW HAVE MID-UPPER 50S ACROSS THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 245 PM CST WED DEC 10 2014
THE START OF THE LONG TERM PERIOD...00Z SUNDAY...HAS NOT SEEN ANY
SIGNIFICANT CHANGES IN THE MODELS...WITH A WELL AMPLIFIED PATTERN IN
PLACE ACROSS THE CONUS...AS RIDGING EXTENDS FROM ERN TX NORTH INTO
ONTARIO...WHILE TROUGHING DIGS SOUTH THROUGH THE ROCKIES. THE MAIN
UPPER LEVEL LOW PRESSURE SYSTEM WHICH WILL BEAR WATCHING IN THE
COMING DAYS IS EXPECTED TO BE IN PLACE OVER THE FOUR CORNERS REGION.
AT THE SURFACE...LOW PRESSURE REMAINS IN PLACE OVER ERN PORTIONS OF
CO...WITH A TROUGH AXIS EXTENDING N/NE INTO THE DAKOTAS...KEEPING
THE SOUTHERLY WINDS GOING ACROSS THE CWA. THE STREAM OF INCREASED
WARM AIR/MOISTURE ADVECTION NORTH INTO THE AREA...KEEPING PLENTY OF
LOW LEVEL CLOUD COVER AROUND...ALONG WITH THE CONTINUED POTENTIAL
DRIZZLE/LIGHT RAIN. OVERNIGHT LOWS SAT NIGHT/SUN MORNING WILL BE
MILD WITH 40S AND A FEW 50S CURRENTLY FORECAST.
SUNDAY AND MONDAY CERTAINLY THE MOST INTERESTING TIME TIME FRAME OF
THE PERIOD...AS WE SEE THE ARRIVAL OF THAT UPPER LEVEL LOW PRESSURE
SYSTEM...AND THE POTENTIAL FOR ACCUMULATING SNOWFALL. DURING THE
DAYTIME HOURS ON SUNDAY...THE LOW IS EXPECTED TO EMERGE OUT OF THE
ROCKIES AND ONTO THE PLAINS...ENDING UP BY 00Z MONDAY ROUGHLY OVER
THE OK/TX PANHANDLE AREA. HOW IT EVOLVES BEYOND THAT AND WHERE ITS
ULTIMATE TRACK ENDS UP WILL DRIVE WHAT OUR CWA SEES SUNDAY NIGHT
THROUGH MONDAY /PERHAPS LINGERING INTO MONDAY NIGHT?/.
PLENTY OF UNCERTAINTY REMAINS WITH THIS SYSTEM. PREVIOUS MODEL RUNS
HAD GENERALLY TAKEN THE SYSTEM ALONG A MORE SOUTHERLY PATH...LEAVING
OUR CWA MORE ON THE NRN EDGE OF THE MAIN ACTIVITY. LOOKING AT THE
12Z RUN OF MODELS TODAY...THE GFS/GEM HAVE A MORE NRN TRACK THROUGH
MONDAY MORNING...TAKING THE 500 AND ESP 700MB LOWS ACROSS CENTRAL
KS...IF NOT RIGHT OVER OUR SRN CWA...AND USHERS IN COLDER
AIR/TRANSITION TO SNOW EVERYWHERE QUICKER. THE LATEST RUN OF THE
ECMWF HOWEVER KEEPS THE TRACK MORE OVER NRN OK...AND IS A TOUCH
SLOWER WITH THE COLDER AIR. THE START OF THIS EVENT IS STILL 4 DAYS
OUT...SO PLENTY EARLY TO BE BUYING FULL IN TO ANY PARTICULAR MODEL
OR MODEL RUN...AS 24 HRS FROM NOW THEY MAY LOOK DIFFERENT.
HOWEVER...EITHER SOLUTION WOULD RESULT IN ACCUMULATING SNOWFALL FOR
THE CWA...DIFFERENCE IS IN WHERE THE HEAVIER /SEVERAL INCHES
POTENTIALLY/ COULD END UP. COMBINED WITH THE EXPECTED GUSTY
NORTHWEST WINDS BUILDING IN BEHIND A PASSING COLD...THOSE WITH
TRAVEL PLANS DURING THIS PERIOD REALLY NEED TO KEEP A CLOSE EYE ON
THE FORECAST IN THE COMING DAYS...LOT OF DETAILS YET TO BE IRONED
OUT. AS FAR AS HIGH TEMPERATURES GO...ON SUNDAY AHEAD OF THE FRONTAL
PASSAGE...HIGHS IN THE MID 40S TO MID 50S ARE CURRENTLY IN THE
FORECAST...WITH LOWER/MID 30S GOING FOR MONDAY.
DRY CONDITIONS RETURN TO THE FORECAST FOR TUESDAY AND WEDNESDAY...AS
UPPER LEVEL SHORTWAVE RIDGING BUILDS IN BEHIND THIS STORM SYSTEM.
CONFIDENCE IN TEMPS IS NOT HIGH....NOT EXPECTING A NOTABLE CHANGE IN
THE OVERALL AIR MASS...BUT SNOWFALL ON THE GROUND WOULD COMPLICATE
THINGS. CURRENT FORECAST HIGHS BOTH DAYS REMAIN IN THE 30S.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1144 PM CST WED DEC 10 2014
REST OF TONIGHT: MVFR STRATUS CIGS WILL GRADUALLY DECAY TO IFR
AND EVENTUALLY LIFR. VSBYS ARE LOWER CERTAIN. SINCE STRATUS HAS
ALREADY INVADED AND ENVELOPED MUCH OF THE REGION...THE POTENTIAL
FOR IFR FOG LOOKS LOW. THIS IS SUPPORTED COMPARING THE CURRENT OBS
TO SIMILAR PAST SITUATIONS. FOR NOW MAINTAINED CONTINUITY WITH THE
PREVIOUS TAF ISSUANCE AT EAR WITH 1/4SM FG OVC002 BUT THIS MAY BE
TOO PESSIMISTIC. LIGHT S WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM
THU: LIFR STRATUS CIGS 300-500 FT AND MVFR VSBYS WILL GRADUALLY
IMPROVE AFTER 16Z...BUT IT WILL BE TOUGH TO GET RID OF THE
STRATUS. CURRENT LOW CLOUD GUIDANCE FROM THE 18Z NAM INDICATES
STRATUS SHOULD BREAK UP 20Z-22Z WITH A BRIEF PERIOD OF VFR
POSSIBLE LATE. S WINDS 10 KTS OR LESS. CONFIDENCE: MEDIUM
THU EVE: PROBABLY VFR TO START BUT CONDITIONS WILL BE FAVORABLE
FOR STRATUS TO REFORM WITH NO APPRECIABLE CHANGE IN THE WX
SITUATION. FCST GUIDANCE DOES NOT APPEAR TO BE HANDLING IT WELL
AND IS IN CONFLICT. NOT SURE IF THIS TURNS OUT A FOG OR A STRATUS
PROBLEM. THE MODIFIED RICHARDSON NUMBER SUGGESTS STRATUS BUT IT
WILL DEPEND ON HOW MUCH RADIATIONAL COOLING OCCURS JUST AFTER
SUNSET. CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR NEZ060-061-
072>074-082>084.
KS...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR KSZ005-006-017-
018.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...WESELY
LONG TERM...ADP
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
402 AM CST THU DEC 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST THU DEC 11 2014
CLOUDS...CLOUDS...CLOUDS! SATELLITE IMAGERY INDICATES LOW-LEVEL
CLOUDS ARE RETURNING FROM THE SOUTHERN SOURCE REGION AND HAVE
OVERTAKEN ALL BUT THE FAR NORTHWEST FA. LOW-LEVEL FLOW DOES NOT
DEVIATE MUCH UNTIL A SFC TROUGH/COLD FRONT IN THE LONG TERM
PERIOD. SOME GUIDANCE INDICATES 925MB RH LOWERING DURING THE
DAYTIME HOURS...BUT 950MB RH REMAINING HIGH. THERE MAY BE SOME
BREAKS IN THE CLOUDS DURING THE DAYTIME HOURS...BUT MOSTLY CLOUDY
CONDITIONS SHOULD PREVAIL. RAP CIG GUIDANCE INDICATES CLOUDS WILL
HOLD TOUGH. OBVIOUSLY...KEEPING LOW CLOUDS IN PLACE WILL HAMPER
TEMPERATURES. THE LONG ADVERTISED WARM-UP LOOKS GOOD AT 4000-5000
FEET ABOVE THE SURFACE...BUT NOT WHERE MOST PEOPLE ACTUALLY LIVE.
THUS...SIGNIFICANTLY LOWERED MAX TEMPS. FOG ALSO
POSSIBLE...ALTHOUGH DO NOT ANTICIPATE DENSE FOG AS SFC WINDS
REMAIN AT LEAST 10 KNOTS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 402 AM CST THU DEC 11 2014
FRIDAY NIGHT-SATURDAY NIGHT...SURFACE TROUGH APPROACHES AND MOVES
THROUGH THE REGION. THIS WILL INCREASE LOW LEVEL MOISTURE EVEN
FURTHER (SFC DEWPOINTS INTO THE MID-UPPER 30S...POSSIBLY 40F). LOW
CLOUDS LIKELY WILL REMAIN...WITH DRIZZLE BECOMING POSSIBLE WITH
WEAK LOW LEVEL LIFT AHEAD OF THE SFC TROUGH. AGAIN...LOWERED MAX
TEMP FOR SATURDAY CONSIDERING EXPECTED LOW CLOUDS...ALTHOUGH NOT AS
MUCH AS PREVIOUS DAYS CONSIDERING THE HIGHER DEWPOINT VALUES.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH REMAINS OVER THE EASTERN
PACIFIC WHILE THE LONG WAVE RIDGE WAS OVER THE NORTHERN PLAINS.
PATTERN DE AMPLIFIES A BIT. LONG WAVE RIDGE RE DEVELOPS OVER THE
ROCKIES AND SHIFTS INTO THE HIGH PLAINS BY THE END OF THE PERIOD.
THE GFS WAS FASTER THAN THE ECMWF THROUGH THE PERIOD. BOTH GFS AND
ECMWF WERE TRENDING SLIGHTLY SLOWER OVER THE LAST COUPLE MODEL
RUNS. WILL PREFER THE ECMWF.
TROUGH OVER THE EASTERN PACIFIC WILL MOVE ACROSS SOUTHERN CANADA BY
SUN/MON AND BRING COOLER AIR T THE AREA.
LITTLE CHANGE TO TEMPS. A DEGREE OR SO HIGHER FOR SUN AND MON AND A
DEGREE LOWER FOR TUE. NO CHANGE FOR WED COMPARED TO YESTERDAYS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1125 PM CST WED DEC 10 2014
IFR CIGS CONTINUE TO SPREAD NORTH ACROSS MOST OF NORTHEAST ND.
HAVE WENT PREDOMINANT IFR FOR ALL SITES EAST OF DVL THROUGH EARLY
TO MID AFTN...AND THROUGH 06Z FRIDAY FOR MN SITES. DVL WILL BE ON
THE EDGE OF A CLEAR/IFR LINE BY MORNING AND IF THEY TREND ANY
FURTHER WEST...WILL NEED TO BE ADJUSTED FOR CIGS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
342 AM CST THU DEC 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST THU DEC 11 2014
CLOUDS...CLOUDS...CLOUDS! SATELLITE IMAGERY INDICATES LOW-LEVEL
CLOUDS ARE RETURNING FROM THE SOUTHERN SOURCE REGION AND HAVE
OVERTAKEN ALL BUT THE FAR NORTHWEST FA. LOW-LEVEL FLOW DOES NOT
DEVIATE MUCH UNTIL A SFC TROUGH/COLD FRONT IN THE LONG TERM
PERIOD. SOME GUIDANCE INDICATES 925MB RH LOWERING DURING THE
DAYTIME HOURS...BUT 950MB RH REMAINING HIGH. THERE MAY BE SOME
BREAKS IN THE CLOUDS DURING THE DAYTIME HOURS...BUT MOSTLY CLOUDY
CONDITIONS SHOULD PREVAIL. RAP CIG GUIDANCE INDICATES CLOUDS WILL
HOLD TOUGH. OBVIOUSLY...KEEPING LOW CLOUDS IN PLACE WILL HAMPER
TEMPERATURES. THE LONG ADVERTISED WARM-UP LOOKS GOOD AT 4000-5000
FEET ABOVE THE SURFACE...BUT NOT WHERE MOST PEOPLE ACTUALLY LIVE.
THUS...SIGNIFICANTLY LOWERED MAX TEMPS. FOG ALSO
POSSIBLE...ALTHOUGH DO NOT ANTICIPATE DENSE FOG AS SFC WINDS
REMAIN AT LEAST 10 KNOTS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 AM CST THU DEC 11 2014
FRIDAY NIGHT-SATURDAY NIGHT...SURFACE TROUGH APPROACHES AND MOVES
THROUGH THE REGION. THIS WILL INCREASE LOW LEVEL MOISTURE EVEN
FURTHER (SFC DEWPOINTS INTO THE MID-UPPER 30S...POSSIBLY 40F). LOW
CLOUDS LIKELY WILL REMAIN...WITH DRIZZLE BECOMING POSSIBLE WITH
WEAK LOW LEVEL LIFT AHEAD OF THE SFC TROUGH. AGAIN...LOWERED MAX
TEMP FOR SATURDAY CONSIDERING EXPECTED LOW CLOUDS...ALTHOUGH NOT AS
MUCH AS PREVIOUS DAYS CONSIDERING THE HIGHER DEWPOINT VALUES.
SUNDAY-WEDNESDAY...WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1125 PM CST WED DEC 10 2014
IFR CIGS CONTINUE TO SPREAD NORTH ACROSS MOST OF NORTHEAST ND.
HAVE WENT PREDOMINANT IFR FOR ALL SITES EAST OF DVL THROUGH EARLY
TO MID AFTN...AND THROUGH 06Z FRIDAY FOR MN SITES. DVL WILL BE ON
THE EDGE OF A CLEAR/IFR LINE BY MORNING AND IF THEY TREND ANY
FURTHER WEST...WILL NEED TO BE ADJUSTED FOR CIGS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...SPEICHER
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1128 PM CST WED DEC 10 2014
.AVIATION...
ALTHOUGH MOST AIRPORTS ARE VFR RIGHT NOW... CEILINGS WILL CONTINUE
TO LOWER OVER THE NEXT FEW HOURS WITH MVFR AND AREAS OF IFR
CEILINGS EXPECTED. HRRR IS STILL POINTING TO THE CHANCE OF DENSE
FOG AT KWWR AND KGAG... BUT CURRENT STRATUS AND OTHER MODELS ARE
MUCH LESS AGGRESSIVE AND OVERALL THE SIGNAL IS MUCH LESS THAN
RECENT NIGHTS.
&&
.PREV DISCUSSION... /ISSUED 932 PM CST WED DEC 10 2014/
UPDATE...
ADDED SPRINKLE WORDING TO ALL BUT FAR WESTERN OKLAHOMA AND
WESTERN NORTH TEXAS AS WEAK NWLY MID-LEVEL WAVE APPROACHES.
RAINFALL EXPECTED TO REMAIN VERY LIGHT AND BRIEF. AREAS OF FOG
EXPECTED ONCE AGAIN...WITH SOME DENSE FOG POSSIBLE OVER FAR
NORTHWEST OKLAHOMA. WITH STRATUS ENTRENCHED ACROSS THE
REGION...WILL BE HARDER FOR DENSE FOG TO DEVELOP BUT NOT OUT OF
THE QUESTION.
PREV DISCUSSION... /ISSUED 539 PM CST WED DEC 10 2014/
AVIATION...
AREAS OF LOW CLOUDS AND FOG WILL AGAIN BE ISSUES WITH THIS SET OF
TAFS. THE HRRR.. RAP AND SREF ARE NOT NEARLY AS BULLISH TODAY WITH
THE DENSE FOG ACROSS THE AREA AS RECENT NIGHTS BUT HIGHLIGHT THE
AREAS OF NORTHWEST OKLAHOMA /SPECIFICALLY KWWR AND POTENTIALLY
KGAG/ WITH THE HIGHEST CHANCE OF DENSE FOG. BUT THE MOS FROM THE
SYNOPTIC MODELS HIT THE FOG POSSIBILITY A LITTLE HIGHER THAN
RECENT NIGHTS. WILL CONFINE THE MENTION OF FG TO KGAG AND KWWR BUT
KEEP A TEMPO GROUP OF 1SM BR IN SOME OF THE OTHER TAF SITES.
REGARDLESS... CEILINGS WILL BE TRENDING DOWN THROUGHOUT THE AREA
OVERNIGHT SO EXPECT WIDESPREAD MVFR CONDITIONS WITH AREAS OF IFR.
THE CEILINGS WILL LIKELY LINGER INTO THE DAY THURSDAY AS LOW LEVEL
HUMIDITY INCREASES.
PREV DISCUSSION... /ISSUED 227 PM CST WED DEC 10 2014/
DISCUSSION...
FOR TONIGHT...AREAS OF DENSE FOG MAY DEVELOP...ESPECIALLY ACROSS
NORTHWEST OKLAHOMA IF CLOUDS CAN CLEAR SOME JUST BEFORE SUNSET.
OTHERWISE...WILL KEEP IN A CHANCE OF DRIZZLE OVER NORTH CENTRAL
OKLAHOMA...WHERE WEAK ASCENT AND HIGHER HUMIDITY WILL OCCUR
THROUGH AT LEAST MIDNIGHT.
LOW CLOUDS AND AREAS OF FOG WILL RETURN THURSDAY NIGHT INTO FRIDAY
AS MOISTURE OVER SOUTH TEXAS GRADUALLY INCREASES. ISENTROPIC
ASCENT WILL REMAIN WEAK...BUT SOUTH CENTRAL AND SOUTHEAST OKLAHOMA
WILL HAVE THE BEST OPPORTUNITY FOR VERY LIGHT RAIN SHOWERS OR
DRIZZLE.
SOUTHERLY WINDS WILL BEGIN TO INCREASE LATE FRIDAY INTO SATURDAY
AS A STRONG SYSTEM MOVES ACROSS CALIFORNIA. MODELS ARE SIMILAR IN
TRACKING THIS SYSTEM ACROSS NORTHERN OKLAHOMA/KANSAS ON SUNDAY.
THIS TRACK WILL BRING DRIER MID AND UPPER LEVEL AIR INTO SOUTHWEST
OKLAHOMA AND NORTH TEXAS AND LIMIT THE AMOUNT OF RAIN. STRONG
SOUTHWEST WINDS WILL ALSO DEVELOP GIVEN THE TIMING OF THE GFS.
ALTHOUGH WIND SHEAR WILL BECOME RATHER STRONG WITH THIS
SYSTEM...INSTABILITY IS EXPECTED TO REMAIN WEAK.
COLDER AND DRIER WEATHER CAN BE EXPECTED MONDAY INTO TUESDAY WITH
STRONG NORTHERLY WINDS MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 44 59 49 62 / 10 10 20 10
HOBART OK 45 60 49 64 / 10 10 10 10
WICHITA FALLS TX 46 64 51 68 / 10 10 10 10
GAGE OK 40 60 44 65 / 10 0 10 10
PONCA CITY OK 40 55 45 59 / 10 10 10 10
DURANT OK 44 55 48 64 / 10 20 30 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1042 PM CST WED DEC 10 2014
.UPDATE...
ISSUED AT 930 PM CST WED DEC 10 2014
MADE SOME ADJUSTMENTS TO THE FORECAST THIS EVENING. SATELLITE
SHOWS LOW STRATUS EXPANDING WEST ACROSS MOST OF THE CWA AND THUS
INCREASED CLOUD OVER. RAP AND HRRR SEEM TO HAVE A GOOD HANDLE AND
SUGGEST THESE LOW CLOUDS END UP COVERING THE ENTIRE CWA...EXCEPT
POSSIBLY GREGORY COUNTY...AND REMAIN INTO AT LEAST THURSDAY
MORNING. WILL HAVE TO WATCH FOR POSSIBLE DENSE FOG FORMATION ON
THE WESTERN EDGE OF THIS STRATUS SHIELD NEAR CHAMBERLAIN...AS SOME
GUIDANCE SUGGESTS THIS IS A POSSIBILITY. GIVEN THE CLOUD
COVER...WARMED LOWS ACROSS THE AREA...AS DO NOT THINK WE WILL SEE
MUCH OF A CHANGE FROM CURRENT READINGS.
OTHER CONCERN IS FREEZING DRIZZLE. STRATUS DEPTH IS PRETTY
SHALLOW...HOWEVER SEEING SOME LIGHT FREEZING DRIZZLE CURRENTLY
OUT THERE. ENOUGH WEAK LIFT IN THE CLOUD LAYER COMBINED WITH CLOUD
TOP COOLING AFTER SUNSET ARE PROBABLY TO BLAME. AS WE GET TOWARDS
MORNING THE MOISTURE BECOMES EVEN SHALLOWER...SO THINK FREEZING
DRIZZLE WILL DECREASE...BUT WILL HAVE TO MONITOR. AT THIS TIME...THINK
THE SHALLOW CLOUD DEPTH WILL PREVENT DRIZZLE FROM BECOMING HEAVY
ENOUGH TO CAUSE ANY MAJOR ISSUES...SO WILL JUST HIGHLIGHT IN AN
SPS...WITH SOME SURFACES POSSIBLY BECOMING A BIT ICY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 234 PM CST WED DEC 10 2014
THE MAIN CONCERNS TONIGHT INTO THURSDAY WILL BE STRATUS. HAVE LEANED
MORE PESSIMISTIC WITH THE THOUGHTS ON CLOUDS. MODELS SHOWING LIGHT
WESTERLY FLOW IN THE 850MB TO 700MB WHICH IS CREATING WEAK WARM AIR
ADVECTION. BELOW THIS THE INVERSION IS STRENGTHENING AS LIGHT
SOUTHERLY TO SOUTHEAST FLOW INCREASES MOISTURE WHICH SHOULD MAKE IT
DIFFICULT FOR MORE THAN A FEW BREAKS TO DEVELOP IN THE STRATUS. IF
WE CAN GET A FEW BREAKS IN THE CLOUD COVER FOG MIGHT BECOME AN ISSUE
BUT FOR NOW BELIEVE THAT MOST OF THE FOG WILL BE IN THE 3 TO 6 MILE
RANGE. SO WITH CLOUDS EXPECTED TO REMAIN IN PLACE THROUGH THE NIGHT
INTO THURSDAY WENT AHEAD AND INCREASED LOWS A BIT TONIGHT AND
DECREASED HIGHS A BIT ON THURSDAY...ESPECIALLY EAST OF THE JAMES
RIVER VALLEY. SO LOWS MAINLY MID TO UPPER 20S AND HIGHS ON THURSDAY
FROM THE MID 30S IN THE FAR EASTERN CWA TO THE LOWER 50S AROUND
GREGORY COUNTY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 234 PM CST WED DEC 10 2014
LOW LEVEL MOISTURE AND STRATUS SEEMS DESTINED TO BE CAMPED OVER
THE SOUTHEAST CORNER OF OUR AREA WILL INTO THE COMING WEEKEND. AT
THIS TIME WE STILL SEEM LIKELY TO KEEP MOSTLY CLEAR SKIES WITH THE
WARMING OVER OUR FAR WESTERN FORECAST AREA...BUT IT IS LIKELY TO BE
A FAIRLY SMALL PART. STRATUS WILL REDEVELOP NORTH/NORTHWEST AGAIN
LATE THURSDAY NIGHT...AT WHICH TIME GREATER AND MUCH DEEPER LOW
LEVEL MOISTURE WILL BEGIN TO ADVECT INTO THE AREA FROM THE SOUTH.
THIS SHOULD LEAD TO FAIRLY SOLID STRATUS HANGING IN OVER THE
SOUTHEAST HALF OF THE AREA FRIDAY AFTERNOON AND EXPANDING A BUT
FURTHER BY SATURDAY. ALONG WITH THIS...WILL KEEP DRIZZLE AND FOG
MENTION SOUTHEAST HALF FOR LATE FRIDAY NIGHT AND SATURDAY. OBVIOUSLY
THE BIG QUESTION IS JUST HOW FAR NORTHWEST THE SOLID CLOUD COVER
WILL GET...AND COULD NOT RULE OUT IT GETTING OVER EVEN THE FAR WEST
FOR A WHILE.
TEMPERATURES WILL CONTINUE TO WARM...ESPECIALLY WITH THAT SURGE
FRIDAY. SOME RECORD HIGH TEMPERATURES SEEM POSSIBLE SOUTHWEST
FRIDAY AND/OR SATURDAY WITH SOME LOWER 60S LIKELY...WITH RECORD HIGH
MINIMUMS EAST BY SATURDAY WHILE DAYTIME TEMPERATURES EAST CREEP
SLOWLY TO NEAR 50...STILL UNSEASONABLY WARM OF COURSE. INTERESTING
TO HAVE DRIZZLE MENTIONED DURING THE NIGHT AT THIS TIME OF YEAR AND
IT WOULD NOT BE FREEZING.
ON A TOSS UP...WILL GO WITH THE LOW POPS IN THE EXTENDED GUIDANCE
AND CARRY PRECIPITATION AS LIGHT RAIN SATURDAY NIGHT AND SUNDAY. WE
ALL KNOW OF COURSE THAT DRIZZLE CAN GET THICK ENOUGH WITH DROPLETS
APPROACHING THE BORDERLINE ZONE TO GET MEASURABLE. BY SUNDAY THERE
COULD BE SOME HIGHER BASED LIGHT RAIN WITH THE APPROACHING WAVE AND
COLD FRONT.
WITH COLDER AIR MONDAY...SYSTEM SHOWN BY MODELS COULD BRING WET
SNOW. GFS SHOWS THE DECENT PRECIPITATION MONDAY AND MONDAY NIGHT
JUST SOUTH OF THE AREA WHILE THE EC IS CLOSE TO INTERSTATE
90...THOUGH IT HAS GONE A BIT SOUTH FROM ITS PREVIOUS RUN. WILL
KEEP POPS MOSTLY AT THE CHANCE LEVEL WITH SOME LIKELIES FAR SOUTH
AND NOT GO WITH A WHOPPER AT THIS TIME.
TUESDAY AND WEDNESDAY SHOULD BE DRY AND SEASONABLY COLD...UNLESS THE
MONDAY SYSTEM SLOWS DOWN A LOT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1041 PM CST WED DEC 10 2014
WITH ABUNDANT STRATUS THROUGHOUT THE EASTERN PLAINS...COUPLED WITH
SURFACE AND LOW LEVEL WINDS REMAINING OUT OF THE SOUTH TO
SOUTHEAST...06Z TAFS WILL LIKELY REFLECT A CONTINUATION OF
WIDESPREAD LIFR TO IFR CONDITIONS THROUGH THURSDAY. CONDITIONS AT
KSUX MAY BE A BIT BETTER...WHEREAS THAT AREA IS RECEIVING MORE
MVFR CONDITIONS. BUT LATE TONIGHT...HAVE THEM NOTCHING DOWN INTO
THE IFR CATEGORY BEFORE GOING LOWER END MVFR TOWARD MIDDAY
THURSDAY. VISIBILITIES ARE A LITTLE HARDER TO ASCERTAIN FOR THE
REST OF TONIGHT AS THERE WILL BE SOME AREAS OF VERY LIGHT
FREEZING DRIZZLE. SO FAR DID NOT INCLUDE THE MENTION OF LIGHT
FREEZING DRIZZLE IN THE TAFS AS IT MAY NOT BE DETECTED ON SENSORS
IT IS SO LIGHT. BUT IT COULD AID IN REDUCING VISIBILITIES AT TIMES
TO AROUND 1 TO 2 MILES...WELL IN THE IFR CATEGORY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...08
LONG TERM...
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS RENO NV
314 AM PST THU DEC 11 2014
.SYNOPSIS...
A SIGNIFICANT WINTER STORM WILL PRODUCE VERY WINDY CONDITIONS OVER
THE REGION TODAY AND TONIGHT. HEAVY RAIN AND SNOW WILL MAINLY
AFFECT NORTHEAST CALIFORNIA TODAY, THEN SPREAD ACROSS THE SIERRA
AND WESTERN NEVADA TONIGHT AND FRIDAY. MAINLY DRY AND COOL
CONDITIONS ARE EXPECTED THIS WEEKEND AS HIGH PRESSURE RETURNS TO
CALIFORNIA AND NEVADA.
&&
.SHORT TERM...
WINDS HAVE BEGUN TO PICK UP IN THE TAHOE BASIN AND FAR WESTERN
NEVADA, WITH GUSTS TO 50 MPH AROUND TRUCKEE, AND 35-45 MPH
BETWEEN RENO AND CARSON CITY. RIDGE GUSTS ALONG THE SIERRA CREST
WEST OF TAHOE HAVE INCREASED TO NEAR 100 MPH. THIS IS JUST THE
START OF THE HIGH WIND EVENT WHICH HAS BEEN ADVERTISED FOR THE
PAST FEW DAYS, AND ALL WARNINGS AND ADVISORIES WILL REMAIN INTACT.
AREAS OF BLOWING DUST HAVE BEEN INCLUDED FOR MUCH OF WESTERN
NEVADA AND EASTERN MONO COUNTY FROM LATE MORNING THROUGH THIS
EVENING, AS MEANINGFUL PRECIPITATION IS NOT EXPECTED TO ARRIVE IN
THESE AREAS UNTIL LATER TONIGHT.
PRECIPITATION SO FAR HAS GENERALLY BEEN CONFINED TO NORTHEAST
CALIFORNIA WHERE RAINFALL BETWEEN 0.50 AND 1 INCH HAS BEEN
MEASURED IN CENTRAL PLUMAS COUNTY AND WESTERN LASSEN COUNTY. THESE
AREAS ARE EXPECTED TO RECEIVE THE LION`S SHARE OF THE RAIN AND
HIGH ELEVATION SNOW FOR MUCH OF TODAY AS MODEL GUIDANCE PULLS THE
MAIN MOISTURE FEED NORTH OF INTERSTATE 80 FOR MUCH OF TODAY.
RECENT RUNS OF THE HRRR MODEL ARE SIMILAR TO THE OPERATIONAL
MODELS, ALTHOUGH A SHORT PERIOD OF RAIN MAY BRUSH ACROSS THE
TRUCKEE-TAHOE VICINITY EARLY THIS MORNING. SNOW LEVELS FROM
PROFILER DATA WEST OF THE SIERRA CREST HAVE GENERALLY HOVERED
AROUND 8500 FEET, EXCEPT DIPPING BELOW 8000 FEET WITHIN HEAVIER
PRECIP BANDS. WE RAISED SNOW LEVELS ABOVE 8000 FEET FOR TAHOE AND
DELAYED DROPPING THE SNOW LEVEL BELOW 7000 FEET UNTIL MID-LATE
AFTERNOON.
FOR NORTHEAST CALIFORNIA, PRECIPITATION WILL GENERALLY FALL AS
RAIN EXCEPT FOR THE HIGHER MOUNTAINS OF WESTERN LASSEN COUNTY
THROUGH TODAY. TRAVEL IMPACTS ARE MORE LIKELY FOR HIGHER ELEVATION
ROADS HIGHWAY 44 WEST OF SUSANVILLE, FREDONYER SUMMIT AND YUBA
PASS BY LATE AFTERNOON OR EARLY EVENING.
FOR TONIGHT, THE MAIN IMPACTS TRANSITION FROM STRONG WINDS TO
HEAVY SIERRA SNOW AND VALLEY RAIN. A RAPID WORSENING OF TRAVEL
CONDITIONS IS EXPECTED EARLY THIS EVENING FOR THE MAIN PASSES
ALONG THE CREST INCLUDING I-80 AND HIGHWAY 50, THEN SPREADING
SOUTH ACROSS ALPINE AND MONO COUNTY LATER THIS EVENING. SNOW
AMOUNTS MAY NOT BE QUITE AS HIGH DUE TO A SHORTER DURATION OF
HEAVY SNOW. HOWEVER, SNOWFALL RATES COULD BE AS HIGH AS 3 INCHES
PER HOUR ABOVE 7000 FEET AND UP TO 2 INCHES PER HOUR IN THE TAHOE
BASIN AFTER THE COLD FRONT PASSES THROUGH DURING THE EVENING.
STEADY SNOW SHOULD CONTINUE THROUGH MID MORNING FRIDAY AROUND
TAHOE, AND INTO THE EARLY AFTERNOON FOR MONO COUNTY BEFORE
TAPERING TO SNOW SHOWERS. MORE INFORMATION ON SNOW AMOUNTS ARE
INCLUDED IN OUR WINTER STORM STATEMENTS.
FOR WESTERN NV, THE BEST CHANCES FOR RAIN WILL ARRIVE AFTER
MIDNIGHT AND CONTINUE THROUGH FRIDAY MORNING. THE GFS AND ECMWF
ARE PROJECTING AROUND 0.50 INCH AROUND RENO-SPARKS, WITH LOCALLY
HIGHER AMOUNTS UP TO 1 INCH POSSIBLE SOUTH OF CARSON CITY. IN
CONTRAST, THE NAM SHOWS MORE SHADOWING WITH PRECIP TOTALS OF 0.25
INCH OR LESS FOR RENO-CARSON-DOUGLAS. DUE TO THE DEEP MOISTURE
AND STRONG FORCING ALONG AND BEHIND THE FRONT, WE ARE FAVORING
THE HIGHER RAIN TOTALS AT THIS TIME. BY FRIDAY, SNOW LEVELS DROP
TO 5000-5500 FEET AS PRECIP WINDS DOWN WITH POSSIBLE LIGHT
ACCUMULATIONS ABOVE 5500 FEET, BUT LITTLE TO NO ACCUMULATION IS
EXPECTED FOR THE HEAVILY POPULATED AREAS OF WESTERN NEVADA.
SNOW SHOWERS WILL CONTINUE DIMINISHING FRIDAY NIGHT AND END BY
SATURDAY MORNING FROM WEST CENTRAL NV TO MONO COUNTY, WITH LITTLE
TO NO ADDITIONAL ACCUMULATIONS EXPECTED. DAYTIME TEMPS WILL BE
NOTABLY COOLER ON SATURDAY BUT NEAR MID DECEMBER NORMALS WITH
HIGHS MAINLY IN THE 40S FOR LOWER ELEVATIONS AND AROUND 40 FOR
SIERRA VALLEYS. MJD
.LONG TERM...SUNDAY THROUGH WEDNESDAY...
LIMITED CHANGES WERE MADE TO THE EXTENDED FORECAST AS MODELS
REMAIN AT ODDS WITH EACH OVER ON THE DETAILS...BUT THE INDIVIDUAL
MODELS ARE CONSISTENT WITH THEMSELVES.
SHORT WAVE RIDGE OVERHEAD SUNDAY SHOULD BRING DRY WEATHER WITH LIGHT
WINDS. BUT A LACK OF MIXING WILL KEEP HIGH TEMPS IN THE VALLEYS FROM
CLIMBING ABOVE AVERAGE.
OPERATIONAL MODELS CONTINUE TO BRING THE NEXT SYSTEM INTO THE REGION
ANYWHERE FROM LATE SUNDAY EVENING...GEM...TO MONDAY AFTERNOON...
ECMWF. GFS IS BETWEEN THOSE TWO. THIS TROUGH IS COMING IN AS AN
ELONGATED SYSTEM WITH A HINT THAT A JET STREAK ROUNDING THE BASE OF
THE TROUGH WILL EITHER FORM A SECONDARY LOW SOUTH OF THE BAY AREA OR
PRODUCE A WEAKLY NEGATIVELY TILTED TROUGH. EITHER SOLUTION WOULD
TEND TO SLOW THE APPROACH OF THE MAIN TROUGH AND PCPN. FOR NOW HAVE
EDGED CLOSER TO ECMWF SOLUTION WITH THIS FEATURE.
OPERATIONAL MODELS ALSO SHOW A SECONDARY SHORT WAVE MOVING THROUGH
THE MAIN LONG WAVE TUESDAY. ECMWF KEEPS THE PATTERN STORMY THROUGH
WEDNESDAY IN WEAK WNW FLOW WHILE THE 00Z GFS SHOWED A BREAK IN THE
SERIES OF SHORT WAVES FOR WEDNESDAY. NOW THE 06Z GFS IS TRENDED MORE
TOWARD THE ECMWF.
BOTTOM LINE. WE SHOULD SEE AT LEAST LOW END POPS IN THE EXTENDED
EVERY DAY STARTING MONDAY. BECAUSE THESE SYSTEMS START
COOLER...SNOW LEVELS WILL BE LOW ENOUGH TO PRODUCE SOME SNOW AT
THE VALLEY FLOORS OF WESTERN NEVADA IF THESE SOLUTIONS HOLD. NONE
OF THESE SYSTEMS HAVE IMPRESSIVE AMOUNTS OF QPF...BUT AT LEAST THE
SIERRA SHOULD ADD A LITTLE TO THE HIGH ELEVATION SNOW PACK.
HIGH TEMPS EACH DAY SHOULD BE AT OR BELOW AVERAGE DUE TO PCPN AND
CLOUD COVER. 20
&&
.AVIATION...
SOUTHERLY GRADIENT WINDS STARTING TO INCREASE QUICKLY THROUGH THE
SIERRA...FAR NORTHEAST CALIFORNIA AND WESTERN NEVADA THIS MORNING.
GUSTS OVER THE SIERRA RIDGES HAVE ALREADY TOPPED 90 KTS WHILE SOME
SIERRA VALLEYS AND AREAS EAST OF THE SIERRA ARE SEEING GUSTS IN THE
45-50 KT RANGE. THIS SHOULD CONTINUE THROUGH THE MORNING HOURS AND
WILL LIKELY SPREAD A BIT FARTHER EAST...ALTHOUGH EAST OF HIGHWAY 95
THE STRONGEST GUSTS MAY NOT TOP 40-45 KT.
GUSTS UPWARDS OF 60-65 KTS ARE POSSIBLE THROUGH THIS EVENING BEFORE
THEY BEGIN TO DECREASE A BIT OVERNIGHT FOR FAR WESTERN NEVADA AND
THE SIERRA. UNIDIRECTIONAL FLOW FROM THE SFC UP TO ABOUT 5000 FT SHOULD
LIMIT DIRECTIONAL SHEAR...BUT THERE IS STILL LIKELY TO BE SOME SPEED
SHEAR THROUGH THE FIRST 4000-5000 FT. TURBULENCE SHOULD BE
WIDESPREAD TODAY AND WILL LIKELY BECOME QUITE ROUGH ON APPROACH AND
AT LOWER TO MID FLIGHT LEVELS OVER THE SIERRA AND TO THE EAST TODAY.
RAIN AND VERY HIGH ELEVATION SNOW HAS MOVED INTO NORTHERN AND FAR
NORTHEAST CALIFORNIA THIS MORNING. THE SHIELD OF PCPN SHOULD DRIFT
SOUTHEAST LATER TODAY AND TONIGHT...DRIVING CIGS TO IFR/MVFR
CONDITIONS AS IT MOVES. LATER THIS EVENING SNOW LEVELS BEGIN TO
DROP IN THE SIERRA FROM HIGHWAY 50 NORTH WITH ACCUMULATING SNOWS
ON SIERRA RUNWAYS. SNOW LEVELS FALL THROUGH MONO COUNTY OVERNIGHT.
BY FRIDAY MORNING WE COULD HAVE 4 TO 12 INCHES ON RUNWAYS IN THE
SIERRA...HIGHER AMOUNTS IF SNOW LEVELS FALL FASTER THROUGH THE
EVENING.
BOTTOM LINE...VERY STRONG WINDS AT THE SFC AND ALOFT TODAY WITH
WIDESPREAD TURBULENCE. DETERIORATING CIGS/VSBYS THROUGH THE
AFTERNOON AND EVENING. MOUNTAIN OBSCURATIONS DEVELOPING ALONG WITH
IFR CONDITIONS IN SNOW OVERNIGHT THROUGH THE SIERRA. LOWERED CIGS
AND RAIN IN WESTERN NEVADA VALLEYS. SNOW ACCUMULATIONS OF 4 TO 12
INCHES LIKELY FOR SIERRA RUNWAYS BY FRIDAY MORNING. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY NVZ003-005.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON NVZ002.
WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO 1 PM PST FRIDAY
NVZ002.
WIND ADVISORY UNTIL 4 AM PST FRIDAY NVZ001-004.
CA...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY CAZ070-071.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 10 AM PST FRIDAY
ABOVE 5000 FEET FOR CAZ071.
HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING CAZ073.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 4 PM PST FRIDAY
CAZ073.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON CAZ072.
WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO 1 PM PST FRIDAY
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
548 AM CST THU DEC 11 2014
.SHORT TERM...
338 AM CST
THROUGH FRIDAY...
AS AN INDICATION OF THE QUIET PERIOD OF WEATHER WE CURRENTLY ARE
EXPERIENCING...THE MAIN FOCUS OF THIS FORECAST PACKAGE AND THE
WEATHER ELEMENT THAT GENERATED THE MOST DISCUSSION BETWEEN
NEIGHBORING OFFICES IS SKY COVER. SO NOT A LOT GOING ON IN THE NEAR
TERM...BUT SKY COVER IS A BIT CHALLENGING AND OF COURSE HAS
RAMIFICATIONS FOR DAYTIME HIGHS AND OVERNIGHT LOWS.
MODELS HAVE NOT REALLY BEEN HANDLING THE SKY TRENDS ALL THAT
WELL...THOUGH LOW LEVELS OF THE NAM AROUND 975 TO 925MB ARE PROBABLY
COMING THE CLOSEST IN DEPICTING THE ONGOING CLOUDINESS. LIKELY
CONTRIBUTING TO MODEL CONFUSION IS THE FACT THAT THE EMBEDDED
CLOUDINESS IS TRAPPED BELOW A STEEP INVERSION UNDER THE AXIS OF THE
STRONG SFC RIDGE SITTING TO OUR WEST...WHILE CLOUDS ARE BEING
SCOURED OUT UNDER THE BETTER MIXED CIRCULATION AROUND THE BACK SIDE
OF THE LOW SITTING OVER NEW ENGLAND. EVEN IF SOME OF THIS MOISTURE
UNDER THE INVERSION DOES BEGIN TO MIX OUT...THERE STILL IS ENOUGH
CYCLONIC FLOW ALOFT AND POCKETS OF SHORTWAVE ENERGY TO SUPPORT THE
IDEA OF CONTINUED CLOUDINESS INTO THE WEEKEND. IF NOTHING
ELSE...PERSISTENCE HAS SO FAR PROVEN EFFECTIVE IN THIS REGIME...SO
DAYTIME HIGHS WILL BE NUDGED SLIGHTLY DOWNWARD AND OVERNIGHT LOWS
SLIGHTLY UPWARD UNTIL BETTER SIGNALS OF CLEARING WOULD INDICATE
OTHERWISE.
LENNING
&&
.LONG TERM...
338 AM CST
FRIDAY NIGHT THROUGH THURSDAY...
FRIDAY NIGHT AND SATURDAY WILL REMAIN DRY AND WE MAY FINALLY SEE A
BIT OF CLEARING AS THE RIDGE AXIS SLOWLY MOVES OVERHEAD...BUT AM
NOT WILLING TO DEVIATE MUCH FROM PERSISTENCE UNTIL THIS ACTUALLY
STARTS HAPPENING. BY SATURDAY NIGHT INTO SUNDAY...AND MORE SO ON
MONDAY INTO TUESDAY...MOISTURE STARTS MAKING A RETURN TO THE AREA
ON THE BACK SIDE OF THE RIDGE THAT HAS FINALLY SLID TO OUR
EAST....THOUGH POPS REMAIN LOW IN THE SLIGHT CHANCE RANGE THROUGH
SUNDAY.
ON MONDAY THE ECMWF AND GFS BOTH SUGGEST THE PRESENCE OF AN
APPROACHING LOW TRACKING ALONG THE 37TH PARALLEL...AND A TROUGH OR
FRONTAL ZONE EXTENDING NORTH OF THIS FEATURE INTO CANADA. ALTHOUGH
THE LOW CENTER MAY PASS TO OUR SOUTH...THERE IS ENOUGH MILD AIR
WRAPPED UP WITH THIS SYSTEM THAT RAIN IS AGAIN THE MOST LIKELY FORM
OF PRECIPITATION AT LEAST UNTIL THE TRAILING RIDGE PUSHES COLDER AIR
INTO THE AREA ON TUESDAY AND WEDNESDAY...AT WHICH POINT MESOSCALE
LAKE EFFECTS WOULD BE THE PRIMARY DRIVER OF LIFT AND SATURATION.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* MVFR CIGS OF 1500-2500 FEET TONIGHT AND TIMING OF IMPROVEMENT ON
THURSDAY.
KREIN
//DISCUSSION...UPDATED 12Z...
AS THE CENTER OF SFC HIGH PRESSURE SAGS SOUTH THROUGH WRN IL AND
INTO THE LOWER OHIO VALLEY...WINDS ACROSS THE REGION ARE BACKING
THROUGH NORTHWESTERLY WITH SPEEDS AT OR SLIGHTLY BELOW 10KT. THE
MAIN CONCERN FOR THE PERIOD WILL BE MVFR CIGS. A PERISITENT LOW
LEVEL INVERSION IS PREVENTING AND DEEP LAYER MIXING AND ANTICIPTE
THAT THE MVFR CIGS WILL HANG IN THROUGH THE PERIOD...DESPITE THE
TRENDS IN THE MODEL GUIDANCE TO WANT TO SCATTER OUT BY THIS
AFTERNOON. FORECAST SOUNDINGS INDICATE THAT THE INVERSION WILL
PERSIST THROUGH THE AFTERNOON AND LIFT WITH DAYTIME WARMING...SO
BASES SHOULD LIFT TO HIGHER END MVFR...BUT THE INVERSION SHOULD
REMAIN STRONG ENOUGH TO PREVENT ANY DEEP LAYER MIXING THAT WOULD
ALLOW FOR CIGS TO IMPROVE. SO WILL MAINTAIN THE MVFR CONDTIONS
THROUGH THE PERIOD.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM CONFIDENCE IN CIGS REMAINING MVFR THROUGH THE PERIOD.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. WX NIL.
SATURDAY...VFR. WX NIL.
SUNDAY...SLIGHT CHANCE RAIN.
MONDAY...CHANCE RAIN. CHANCE MVFR CIGS.
TUESDAY...CHANCE RAIN MIXING WITH SNOW LATE.
WEDNESDAY...VFR. WX NIL.
KREIN
&&
.MARINE...
315 AM CST
PERSISTENT NWLY FLOW WILL CONTINUE OVER THE NEXT FEW DAYS AS HIGH
PRESSURE BUILDS ACROSS THE MISSISSIPPI VALLEY AND WESTERN GREAT
LAKE S REGION AND DEEP LOW PRESSURE SLOWLY MOVES THROUGH NEW
ENGLAND. THE HIGH PRESSURE WILL GRADUALLY SLIDE SOUTH INTO THE
LOWER OHIO VALLEY AND LOWER MISSISSIPPI VALLEY AS A TROUGH OF LOW
PRESSURE DEVELOPS OVER THE NORTHERN PLAINS AND THE NEW ENGLAND LOW
BEGINS TO LIFT OUT TO THE NORTHEAST. WINDS OVER THE LAKE WILL
GRADUALLY BACK THROUGH WESTERLY TO SOUTHWESTERLY BY SATURDAY
NIGHT. A MODERATE GRADIENT WILL REMAIN IN PLACE OVER THE LAKE
THROUGH THE PERIOD WITH WINDS GENERALLY IN THE 15-25 KT RANGE WITH
OCNL PERIODS OF 30KT WINDS.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
540 AM CST Thu Dec 11 2014
.SHORT TERM...(Today)
ISSUED AT 336 AM CST THU DEC 11 2014
Little relief from the cloud cover is expected today. Some clearing
has developed over lower Michigan and northern Indiana, but NW
surface winds will not be conducive to pulling that dry air into
Illinois. An expansive area of clouds remains entrenched across the
Midwest back to the eastern Dakotas and south to Texas. Besides an
isolated break in the clouds this afternoon in eastern areas, it
looks likely that the strong low level temperature inversion will
provide cloudy skies for at least another day.
Diurnal temperature swings yesterday were only 4 degrees in most
areas, and similar conditions are expected today with little to no
airmass change and little to no sunshine. Will keep highs in the mid
to upper 30s with light northwest winds under stalled high pressure.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 336 AM CST THU DEC 11 2014
Clouds that will not go away...that is the first and major issue
with this forecast. Considering the strength of the inversion in the
forecast soundings...the satellite imagery, and the persistence
forecast, have completely ignored the modeled sky cover. Keeping
the majority of the forecast in the shorter term covered in stratus.
As a result, adjusting the temperatures a bit to cooler in the day
time and warmer in the overnights. Southerly winds kicking in on
Friday though will help with WAA without too much in the way of
sunshine. Temps over the weekend well above normal, though cloudy.
Best chances to see broken clouds may be on Saturday before clouding
up again in advance of the next system.
Precip chances return late in the weekend...Sunday night...and into
the first of the work week, though the confidence in the upper air
pattern is low. Have been too many iterations about handling the
500mb low/trof. That being said, the surface forecast remains rain,
just a question of when. The timing of the low and the track are
starting to diverge yet again, though the models are wet Monday and
Monday night...now lingering into Tuesday. Best chances are Monday
and Monday night, with some warm advection showers possible late
Sunday night.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 540 AM CST THU DEC 11 2014
The NAM/GFS/HRRR all continue to advertise some clearing across
central IL today. The HRRR shows clearing developing near CMI
around 19z and expanding toward PIA and SPI the rest of the
afternoon. The subsidence inversion remains as strong as it has
been the last few days, and the depth of the cloud layer remains
at 1.5-2k feet. While a few breaks may develop today, especially
toward CMI, we will continue the cloudy MVFR forecast until
satellite and obs confirm changes in that pattern. Winds will
be light northwest this morning, with a shift toward more westerly
by afternoon, as a surface ridge axis shifts just east of the
area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS TOPEKA KS
927 AM CST Thu Dec 11 2014
.UPDATE...
Issued at 927 AM CST THU DEC 11 2014
Did a quick update to maintain overcast skies through the day. RAP
forecast soundings fail to mix out the boundary layer and maintain
the low level saturation through the day. Given the expanse of the
low level stratus, think it is more likely for the clouds to
remain in place than the chance to see the sun this afternoon.
Also the RAP and NAM keep some hint of weak isentropic upglide
through the afternoon along and south of I-70. This could aid in
keeping a light mist or drizzle going into the afternoon. Have not
done anything with afternoon highs since winds still appear to
veer to the southeast with a chance for some warm air advection.
If surface winds remain out of the east, forecast highs may be a
little optimistic.
&&
.SHORT TERM...(Today and Tonight)
Issued at 331 AM CST THU DEC 11 2014
Northerly flow aloft was in place across the central U.S. as a
strong closed-off low was centered over the New England area and a ridge
axis was situated over the Rockies. Water vapor imagery showed a
weak embedded shortwave over Kansas that was slowly sliding
southeastward. Some isentropic lift on the 290K-300K surface was
noted with this shortwave. This lift combined with continued
low-level saturation resulted in areas of drizzle developing early
this morning across much of the southeastern two-thirds of the forecast
area. With temperatures holding fairly steady around 34F-35F and
dewpoint temperatures generally around 33F-34F, do not anticipate
wet-bulb cooling to drop temperatures below freezing in this region
so expect this light precipitation to stay in the form of drizzle.
The only area worth watching is across far northeast Kansas along
the Kansas/Nebraska border where surface and dewpoint temperatures
are a couple of degrees cooler. If any of this drizzle were to
extend that far north then some light freezing drizzle and some
resultant slick spots on the roadways would be possible. In addition
to the drizzle, this low-level saturation combined with light
easterly winds due to the surface high located just east of the area
will result in areas of fog remaining in place across the forecast
area through mid to late morning.
Expect these areas of drizzle to persist through the morning hours,
but model soundings show some dry air working into the area just
above the surface by this afternoon so may see a brief break in the
drizzle. While the cloud cover may thin out some across north
central Kansas, still expect overcast skies to prevail through the
day with light southeasterly winds helping to boost afternoon
temperatures a few degrees warmer than yesterday, into the low 40s.
Model soundings show the dry air just above the surface becoming
saturated once again and should keep this low-level saturation in
place through the overnight hours tonight. As a result, expect areas
of drizzle to develop once again along with areas of fog, especially
across far northern Kansas near the Kansas/Nebraska border. With
overcast skies in place and winds veering more toward the
south-southeast, overnight low temperatures should only drop into
the mid 30s to around 40 degrees from north to south. As a result,
this very light precipitation should stay in the form of light
drizzle.
.LONG TERM...(Friday through Wednesday)
Issued at 331 AM CST THU DEC 11 2014
A deepening upper level trough will move off the eastern Pacific and
into the western CONUS Friday and Saturday resulting in a ridge
building across the Plains. Southerly flow will commence ahead of
the approaching system along with a moderation in temperatures
through the weekend. Forecast sounding continue to show the low
level moisture will continue in the low levels and increase in
depth. Also temperatures through the column continue to warm with
temps reaching around 11 Celsius at 850 MB on Saturday. Temperatures
will warm into the 50s Friday and Saturday with some 60s on Sunday
in the warm advection pattern.
On Friday will continue to see areas of drizzle and fog especially
in the morning when there is upward vertical motion in the moist
layer, however by afternoon the lift decreases and expect cloudy
skies to continue through the afternoon and early evening before the
next round of drizzle and fog develops Friday night and early
Saturday. The clouds will keep temperatures from falling much
overnight with lows in the 40s Saturday morning and in the 50s
Sunday morning.
There is still discrepancy between the models with the handling of
the upper trough moving through the Plains late in the weekend into
Monday. The GFS is faster than the GEM and ECMWF and is also a
little further north. Have continued to lean in the direction of the
ECMWF and the ECMWF mean as well as the GEM which are in closer
agreement. This will affect how quickly cold air will arrive for any
change over or mix with snow. The colder air looks to hold off in
the north central Kansas counties of the forecast area until the
latter part of the day on Monday. With a good conveyor of moisture
around the upper level system, the deformation zone sets up across
the forecast Sunday night and Monday which will yield moderate
rainfall amounts. Some areas could see 1+ inches. Have removed
mention of thunderstorms for Sunday afternoon as elevated
instability is forecast to be southwest of the forecast area.
The upper trough moves out Monday night with the cold air
overspreading the rest of the forecast area. Currently will continue
with a rain and snow mix, but areas in north central Kansas and near
the Nebraska border may change over to all snow before precipitation
ends. Little accumulation of wintry precipitation is expected at
this time. Dry weather is expected for Tuesday and Wednesday with
highs in the 30s and lows in the 20s. Another storm system will move
across the western CONUS Wednesday with precipitation developing
over the forecast area Wednesday night as energy ejects out into the
Plains.
&&
.AVIATION...(For the 12Z TAFs through 12Z Friday Morning)
Issued at 555 AM CST THU DEC 11 2014
For the 12Z TAFs, periods of drizzle and areas of fog will result in
continued IFR to LIFR conditions through the end of the TAF period.
While visibilities will gradually improve through the morning,
CIGS should only improve to high-end IFR conditions but cannot rule
out some brief periods of low-end MVFR CIGS this afternoon. Drizzle
should develop once again by tonight with more widespread areas of
fog developing overnight into Friday morning with at least LIFR
conditions possible.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...Wolters
SHORT TERM...Hennecke
LONG TERM...53
AVIATION...Hennecke
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1043 AM EST Thu Dec 11 2014
...Forecast Update...
Issued at 1042 AM EST Thu Dec 11 2014
Clearing over southern Michigan and much of eastern IN and Ohio has
worked southward into the eastern parts of the forecast area.
Partly sunny skies were noted in areas along and east of
I-65...while mostly cloudy skies lingered out across the west.
Expect more partial clearing to take place through the afternoon
hours, though our far western sections may end up staying mostly
cloudy for much of the day. While clearing has taken place this
morning, expect cold air stratocumulus to redevelop some, but
overall, partly sunny conditions should remain. Despite the
sunshine, temperatures will remain cold with highs topping out in
the upper 30s in the east with some lower 40s possible down across
the KY/TN border region.
Current forecast has this well in hand. However, we did adjust the
hourly temperatures and dewpoints slightly to better match up with
current observations. Also made some minor adjustments to the cloud
cover based on latest satellite imagery and trends.
.SHORT TERM (Now through Friday)...
Issued at 304 AM EST Thu Dec 11 2014
Clouds are again the main challenge with this forecast package.
Overcast conditions continued early this morning across southern
Indiana and central Kentucky. However, dry low level air was
punching from Quebec through Michigan into Indiana and Ohio on the
back side of cyclonic circulation over New England. By 3am the
clearing line had made it down to the I-70 corridor from
Indianapolis to Columbus. The HRRR has been doing the best job
overnight with this clearing line, with some support from 0.5km RH
progs from the GFS. These models bring the clearing line into
central and eastern parts of the LMK CWA over the course of the day,
and we`ll time it as such in the grids. West of I-65 is more of a
question mark, with models wanting to clear skies there as well but
satellite showing less clearing and more cloudiness upstream of
those areas. So, will hold on to the clouds longer in the west than
in the east.
High temperatures today should be around 40 degrees with northwest
breezes this morning becoming westerly this afternoon.
Tonight high pressure will build into the middle Mississippi and
lower Ohio Valleys. The models clear our skies out, which normally
makes sense with domes of high pressure. However, the high is
currently over the upper Mississippi Valley where it`s...cloudy.
So, there is some question whether or not we`ll really clear out
tonight. Even the wetter model solutions give us mostly clear
skies, though, so will lean on the side of fewer clouds for the
overnight hours at this time. It will be interesting to watch the
clouds to our northwest today to see if they slide southeast along
with the high or not. Big potential for a busted forecast tonight
re: sky cover.
Low temperatures tonight will depend a lot on how much cloud we end
up with. For now will stick with mid 20s. Warmer if we stay cloudy.
On Friday that high pressure system will be right on top of us,
giving us partly cloudy skies and high temperatures in the middle
and upper 40s with light winds.
.LONG TERM (Friday Night through Wednesday)...
Issued at 235 AM Thu Dec 11 2014
The upper level pattern by Friday night is expected remain highly
amplified across the CONUS, with a closed low across New England and
a deepening shortwave trough pushing into California. In between,
the blocking pattern will enhance the ridge through the central
Plains into southern Canada. At the surface, high pressure will
remain across the Mid-Mississippi and Ohio River Valleys.
Forecast challenge Friday night into Saturday is focused on cloud
cover and its impacts on temperatures. Despite very dry air above
850 mb, we`ll be dealing with some low-level moisture issues. 11.00z
guidance, particularly the NAM and GEM, suggest a strong inversion
sets up through about 925 mb, or the lowest 2500 ft, with increasing
saturation Friday night. A stratus deck would push into the region
from Upper MS River Valley based on model RH fields and would
persist through the day on Saturday. SREF probabilities for this
deck developing are currently running at or above 70 percent,
especially across the northern half of the local area. Models this
time of year struggle with low-level moisture, but given the
environmental setup, the fact that stratus is already present across
much of the central and northern Plains and the majority of the
models showing this solution, confidence is higher than average. As
such, increased cloud cover during this period and tempered the
diurnal temperature trend as well, favoring the warmer guidance for
Saturday morning lows and cooler guidance for highs.
Going into Sunday, clouds will once again be the main issue to deal
with across the Ohio Valley. Soundings differ in terms of the
strength, but all show the low level inversion remaining in place
around 925 mb, strongest along the KY/IN border and points north.
The surface high and upper level ridge axis are expected to be
directly over the region, resulting in an impressive light wind
layer /less than 10 kts through 25 kft/. If stratus is around, there
won`t be much wind to push/scour/mix it out. Again, increased cloud
cover some and lowered highs/raised lows, especially north of the KY
parkways.
By early next week, the major West Coast storm system will move
across the southern Plains and lift toward the Ohio Valley. The last
several cycles of model runs have shown high variability in the
track of this system, but the 11.00z runs seem to have come
together, bringing the system through Missouri and right across
KY/IN. Rain chances will spread in Monday, becoming likely Monday
night into Tuesday morning, then clearing out late Tuesday.
Confidence continues to increase, so POPs were adjusted higher. In
the wake of this system, a period of drier weather and seasonable
temperatures looks likely followed by the possibility of another
southern stream storm system for late next week into the following
weekend.
&&
.AVIATION (12Z TAF Update)...
Issued at 625 AM EST Thu Dec 11 2014
Clouds remain the main TAF problem. High-end MVFR ceilings
continue to dominate from the Missouri Valley through the Ohio
Valley to New England. However, dry air around 800m streaming from
eastern Canada into the Great Lakes is punching southward behind the
big East Coast storm`s circulation. While the main thrust of this
dry air will be into Ohio for the next several hours, eventually it
should make it down to LEX, and then SDF, and then BWG over the
course of the day. Attempting to time clearing of stratus is
fraught with peril, but going on satellite trends and the HRRR
(which verified very well at 11Z with the clearing line), will bring
VFR conditions into the northern TAF sites by lunch time, and to BWG
by mid afternoon. This is an hour or two later than the previous TAF
package at SDF and LEX.
The remainder of the TAF period will then be quiet.
Surface winds will come in from the northwest this morning, shifting
to the west at 5 to 10 knots this afternoon ahead of a dome of high
pressure over the middle Mississippi Valley. Winds will be nearly
calm tonight as the high moves in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........MJ
Short Term.....13
Long Term......ZBT
Aviation.......13
AREA FORECAST DISCUSSION
NWS JACKSON KY
1001 AM EST THU DEC 11 2014
.UPDATE...
ISSUED AT 1001 AM EST THU DEC 11 2014
UPDATED THE SKY GRIDS BASED ON LATEST MODEL RUNS AND TRENDS IN
SATELLITE IMAGERY. CLEARING SHOULD PROGRESS THROUGH THE REMAINDER OF
THE AREA DURING THE DAY...WITH CLEAR OR MOSTLY CLEAR SKIES THEN
PERSISTING THROUGH FRIDAY.
UPDATE ISSUED AT 620 AM EST THU DEC 11 2014
DID A QUICK TOUCH UP ON THE HOURLY T/TD AND SKY GRIDS TO REFLECT THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM EST THU DEC 11 2014
07Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING INTO KENTUCKY...THOUGH
A LAYER OF STRATOCU CLOUDS REMAIN...BLANKETING THE CWA AND KEEPING
TEMPERATURES FROM FALLING OFF TOO FAST THIS NIGHT. READINGS AT 2 AM
VARIED FROM THE UPPER 20S ON THE RIDGES TO THE LOWER 30S IN THE
VALLEYS WHILE DEW POINTS HAD FALLEN TO THE LOWER 20S FOR MOST OF THE
AREA. CAA CONTINUES ON NORTH TO NORTHWEST WINDS OF 5 TO 10 KTS...WITH
A COUPLE OF HIGHER GUSTS NOTED ON THE RIDGES.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT FOR THE SHORT TERM
PORTION OF THE FORECAST AS THEY ALL DEPICT THE BLOCKING LOW IN PLACE
OVER SOUTHERN NEW ENGLAND ONLY SLOWLY PIVOTING AWAY TO THE NORTHEAST
THROUGH THE PERIOD. LOCALLY...THIS WILL ALLOW HEIGHTS TO GRADUALLY
RISE OVER EASTERN KENTUCKY...BUT NOT BEFORE ONE FINAL BATCH OF ENERGY
SHIFTS SOUTHEAST OF THE AREA THIS MORNING. OTHERWISE...A QUIET
PATTERN WILL ENSUE WITH LITTLE IN THE WAY OF ENERGY AFFECTING THE
STATE IN NORTH TO NORTHWEST FLOW LATER TODAY AND THROUGH THE DAY
FRIDAY. GIVEN THE MODEL AGREEMENT HAVE FOLLOWED THE HIGHER RESOLUTION
NAM12 AND HRRR MOST CLOSELY FOR WX DETAILS IN THE SHORT TERM.
THE MAIN QUESTION TODAY WILL BE HOW QUICKLY THE LOW CLOUDS IN PLACE
OVER THE AREA WILL BREAK UP. THE TIME HEIGHTS FROM THE NAM SUGGESTS
THAT THEY WOULD LINGER INTO THE AFTERNOON...HOWEVER...THE RECENT
SATELLITE LOOP SHOW CLEARING PUSHING QUICKLY SOUTH FROM NORTHERN
OHIO. ACCORDINGLY...HAVE BROUGHT THE LOWER PERCENTAGES OF CLOUD
COVER INTO EAST KENTUCKY A BIT SOONER THAN THE PREVIOUS FORECAST AND
THE NAM12 DEPICTION. OTHERWISE...MOSTLY CLEAR SKIES WILL BE THE RULE
THROUGH FRIDAY ONCE THAT DRIER AIR MOVES INTO THE CWA. THIS WILL LEAD
TO A SMALL TO MODERATE RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT...
WITH THE HIGH CENTER JUST TO THE WEST OF THE CWA. ONLY A SLOW
MODERATION OF THIS HIGH CAN BE EXPECTED SO HIGHS TODAY AND TOMORROW
WILL STILL BE ON THE CHILLY SIDE OF NORMAL...THOUGH FRIDAY WILL BE
SEVERAL DEGREES WARMER THAN TODAY WITH MORE SUNSHINE.
USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND GRIDS WITH
SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT. AS FOR POPS AND WX...
KEPT THEM LOW AND NON-EXISTENT THROUGH FRIDAY GIVEN THE HIGH PRESSURE
REGIME NOW IN PLACE...IN LINE WITH MOS GUIDANCE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 AM EST THU DEC 11 2014
THERE WAS GOOD MODEL AGREEMENT IN THE EXTENDED PORTION OF THE
FORECAST. BOTH THE GFS AND ECMWF BEGIN THE PERIOD WITH A LARGE RIDGE
OF HIGH PRESSURE SITUATED ACROSS A LARGE PORTION OF THE CENTRAL AND
EASTERN CONUS FROM FRIDAY NIGHT THROUGH MONDAY. THIS RIDGE LOOKS TO
BE QUITE STRONG AND THE MODELS DO NOT BEGIN MOVING IT OFF TO THE
EAST UNTIL MONDAY NIGHT...AS A FAIRLY WELL DEVELOPED AREA OF LOW
PRESSURE TAKES SHAPE OVER THE CENTRAL PLAINS. AS THIS SYSTEM BEGINS
TO MOVE EAST...THE RIDGE WILL FINALLY BEGIN TO GIVE GROUND AND MOVE
OFF TO OUR EAST AND EVENTUALLY THROUGH THE MID ATLANTIC REGION AND
OUT TO SEA BY EARLY TUESDAY MORNING. AS THE CENTRAL PLAINS
APPROACHES...CLOUD COVER WILL BE ON THE INCREASE MONDAY AFTERNOON
AND EVENING. TEMPERATURES WILL WARM UP QUITE NICELY ON MONDAY...AS
SOUTHERLY WINDS AHEAD OF THE APPROACHING SYSTEM BRING WARM MOIST AIR
OFF THE GULF OF MEXICO INTO THE REGION. BASED ON THE LATEST TIME
HEIGHT CROSS SECTIONS...IT APPEARS THAT PRECIPITATION ONSET WILL
HOLD UNTIL AROUND 0Z ON TUESDAY...OR UNTIL THE SHORTWAVE MOVES OUT
OF THE CENTRAL MISSISSIPPI VALLEY REGION AND ACROSS THE OHIO AND
TENNESSEE VALLEYS. THE WAVE LOOKS TO BE FAIRLY PROGRESSIVE...WITH
THE BEST CHANCES FOR RAIN OCCURRING MONDAY NIGHT AND TUESDAY.
UPSLOPE FLOW AND RESIDUAL MOISTURE BEHIND THE DEPARTING LOW WILL
KEEP A CHANCE OF SCATTERED RAIN SHOWERS IN THE FORECAST THROUGH
WEDNESDAY MORNING.
TEMPERATURES TO BEGIN THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL...WITH FORECAST HIGHS ON SATURDAY AND SUNDAY TOPPING OUT IN
THE MID 40S. MONDAY LOOKS TO BE WARMER THAN NORMAL IN THE RETURN
FLOW OFF THE GULF...WITH HIGHS ON MONDAY EXPECTED TO RISE INTO THE
LOW TO MID 50S ACROSS THE AREA. THE WEATHER WILL BE SLIGHTLY COOLER
ON TUESDAY DUE TO WIDESPREAD CLOUD COVER AND PRECIPITATION. HIGHS ON
MONDAY ARE EXPECTED TO TOP OUT AROUND 50. ONCE WINDS SHIFT TO THE
NORTHWEST BEHIND THE DEPARTING SYSTEM...COLDER AIR WILL BEGIN TO
SPILL INTO THE AREA...ALLOWING FOR HIGHS IN THE LOW TO MID 40S ON
WEDNESDAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 20S AND LOWER 30S
FRIDAY THROUGH SUNDAY NIGHT...BEFORE CLOUD COVER MOVES BACK IN AND
WINDS SHIFT TO THE SOUTH. THE MERCURY WILL NOT FALL AS MUCH MONDAY
NIGHT AND TUESDAY NIGHT DUE TO THE INFLUENCE OF CLOUD COVER AND
SOUTHERLY WINDS. LOWS THOSE TWO NIGHTS SHOULD ONLY FALL INTO THE
UPPER 30S FOR MOST FOLKS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 635 AM EST THU DEC 11 2014
NORTHWEST FLOW CONTINUES TO KEEP THE LOW STRATOCU DECK IN PLACE OVER
EASTERN KENTUCKY THIS MORNING. CIGS ARE HOLDING JUST ON THE MVFR SIDE
OF THE LINE BETWEEN 2000 AND 2500 FEET. FOLLOWING SUNRISE...CIGS ARE
EXPECTED TO TREND TOWARDS IMPROVING CONDITIONS AND VFR TERRITORY
BEFORE BREAKING UP COMPLETELY INTO EARLY AFTERNOON FOR MOST OF THE
AVIATION SITES. WINDS WILL GENERALLY FLOW OUT OF THE NORTHWEST
THROUGH THE PERIOD AT AROUND 5 KTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
635 AM EST THU DEC 11 2014
.UPDATE...
ISSUED AT 620 AM EST THU DEC 11 2014
DID A QUICK TOUCH UP ON THE HOURLY T/TD AND SKY GRIDS TO REFLECT THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM EST THU DEC 11 2014
07Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING INTO KENTUCKY...THOUGH
A LAYER OF STRATOCU CLOUDS REMAIN...BLANKETING THE CWA AND KEEPING
TEMPERATURES FROM FALLING OFF TOO FAST THIS NIGHT. READINGS AT 2 AM
VARIED FROM THE UPPER 20S ON THE RIDGES TO THE LOWER 30S IN THE
VALLEYS WHILE DEWPOINTS HAD FALLEN TO THE LOWER 20S FOR MOST OF THE
AREA. CAA CONTINUES ON NORTH TO NORTHWEST WINDS OF 5 TO 10 KTS...WITH
A COUPLE OF HIGHER GUSTS NOTED ON THE RIDGES.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT FOR THE SHORT TERM
PORTION OF THE FORECAST AS THEY ALL DEPICT THE BLOCKING LOW IN PLACE
OVER SOUTHERN NEW ENGLAND ONLY SLOWLY PIVOTING AWAY TO THE NORTHEAST
THROUGH THE PERIOD. LOCALLY...THIS WILL ALLOW HEIGHTS TO GRADUALLY
RISE OVER EASTERN KENTUCKY...BUT NOT BEFORE ONE FINAL BATCH OF ENERGY
SHIFTS SOUTHEAST OF THE AREA THIS MORNING. OTHERWISE...A QUIET
PATTERN WILL ENSUE WITH LITTLE IN THE WAY OF ENERGY AFFECTING THE
STATE IN NORTH TO NORTHWEST FLOW LATER TODAY AND THROUGH THE DAY
FRIDAY. GIVEN THE MODEL AGREEMENT HAVE FOLLOWED THE HIGHER RESOLUTION
NAM12 AND HRRR MOST CLOSELY FOR WX DETAILS IN THE SHORT TERM.
THE MAIN QUESTION TODAY WILL BE HOW QUICKLY THE LOW CLOUDS IN PLACE
OVER THE AREA WILL BREAK UP. THE TIME HEIGHTS FROM THE NAM SUGGESTS
THAT THEY WOULD LINGER INTO THE AFTERNOON...HOWEVER...THE RECENT
SATELLITE LOOP SHOW CLEARING PUSHING QUICKLY SOUTH FROM NORTHERN
OHIO. ACCORDINGLY...HAVE BROUGHT THE LOWER PERCENTAGES OF CLOUD
COVER INTO EAST KENTUCKY A BIT SOONER THAN THE PREVIOUS FORECAST AND
THE NAM12 DEPICTION. OTHERWISE...MOSTLY CLEAR SKIES WILL BE THE RULE
THROUGH FRIDAY ONCE THAT DRIER AIR MOVES INTO THE CWA. THIS WILL LEAD
TO A SMALL TO MODERATE RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT...
WITH THE HIGH CENTER JUST TO THE WEST OF THE CWA. ONLY A SLOW
MODERATION OF THIS HIGH CAN BE EXPECTED SO HIGHS TODAY AND TOMORROW
WILL STILL BE ON THE CHILLY SIDE OF NORMAL...THOUGH FRIDAY WILL BE
SEVERAL DEGREES WARMER THAN TODAY WITH MORE SUNSHINE.
USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND GRIDS WITH
SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT. AS FOR POPS AND WX...
KEPT THEM LOW AND NON-EXISTENT THROUGH FRIDAY GIVEN THE HIGH PRESSURE
REGIME NOW IN PLACE...IN LINE WITH MOS GUIDANCE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 AM EST THU DEC 11 2014
THERE WAS GOOD MODEL AGREEMENT IN THE EXTENDED PORTION OF THE
FORECAST. BOTH THE GFS AND ECMWF BEGIN THE PERIOD WITH A LARGE RIDGE
OF HIGH PRESSURE SITUATED ACROSS A LARGE PORTION OF THE CENTRAL AND
EASTERN CONUS FROM FRIDAY NIGHT THROUGH MONDAY. THIS RIDGE LOOKS TO
BE QUITE STRONG AND THE MODELS DO NOT BEGIN MOVING IT OFF TO THE
EAST UNTIL MONDAY NIGHT...AS A FAIRLY WELL DEVELOPED AREA OF LOW
PRESSURE TAKES SHAPE OVER THE CENTRAL PLAINS. AS THIS SYSTEM BEGINS
TO MOVE EAST...THE RIDGE WILL FINALLY BEGIN TO GIVE GROUND AND MOVE
OFF TO OUR EAST AND EVENTUALLY THROUGH THE MID ATLANTIC REGION AND
OUT TO SEA BY EARLY TUESDAY MORNING. AS THE CENTRAL PLAINS
APPROACHES...CLOUD COVER WILL BE ON THE INCREASE MONDAY AFTERNOON
AND EVENING. TEMPERATURES WILL WARM UP QUITE NICELY ON MONDAY...AS
SOUTHERLY WINDS AHEAD OF THE APPROACHING SYSTEM BRING WARM MOIST AIR
OFF THE GULF OF MEXICO INTO THE REGION. BASED ON THE LATEST TIME
HEIGHT CROSS SECTIONS...IT APPEARS THAT PRECIPITATION ONSET WILL
HOLD UNTIL AROUND 0Z ON TUESDAY...OR UNTIL THE SHORTWAVE MOVES OUT
OF THE CENTRAL MISSISSIPPI VALLEY REGION AND ACROSS THE OHIO AND
TENNESSEE VALLEYS. THE WAVE LOOKS TO BE FAIRLY PROGRESSIVE...WITH
THE BEST CHANCES FOR RAIN OCCURRING MONDAY NIGHT AND TUESDAY.
UPSLOPE FLOW AND RESIDUAL MOISTURE BEHIND THE DEPARTING LOW WILL
KEEP A CHANCE OF SCATTERED RAIN SHOWERS IN THE FORECAST THROUGH
WEDNESDAY MORNING.
TEMPERATURES TO BEGIN THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL...WITH FORECAST HIGHS ON SATURDAY AND SUNDAY TOPPING OUT IN
THE MID 40S. MONDAY LOOKS TO BE WARMER THAN NORMAL IN THE RETURN
FLOW OFF THE GULF...WITH HIGHS ON MONDAY EXPECTED TO RISE INTO THE
LOW TO MID 50S ACROSS THE AREA. THE WEATHER WILL BE SLIGHTLY COOLER
ON TUESDAY DUE TO WIDESPREAD CLOUD COVER AND PRECIPITATION. HIGHS ON
MONDAY ARE EXPECTED TO TOP OUT AROUND 50. ONCE WINDS SHIFT TO THE
NORTHWEST BEHIND THE DEPARTING SYSTEM...COLDER AIR WILL BEGIN TO
SPILL INTO THE AREA...ALLOWING FOR HIGHS IN THE LOW TO MID 40S ON
WEDNESDAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 20S AND LOWER 30S
FRIDAY THROUGH SUNDAY NIGHT...BEFORE CLOUD COVER MOVES BACK IN AND
WINDS SHIFT TO THE SOUTH. THE MERCURY WILL NOT FALL AS MUCH MONDAY
NIGHT AND TUESDAY NIGHT DUE TO THE INFLUENCE OF CLOUD COVER AND
SOUTHERLY WINDS. LOWS THOSE TWO NIGHTS SHOULD ONLY FALL INTO THE
UPPER 30S FOR MOST FOLKS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 635 AM EST THU DEC 11 2014
NORTHWEST FLOW CONTINUES TO KEEP THE LOW STRATOCU DECK IN PLACE OVER
EASTERN KENTUCKY THIS MORNING. CIGS ARE HOLDING JUST ON THE MVFR SIDE
OF THE LINE BETWEEN 2000 AND 2500 FEET. FOLLOWING SUNRISE...CIGS ARE
EXPECTED TO TREND TOWARDS IMPROVING CONDITIONS AND VFR TERRITORY
BEFORE BREAKING UP COMPLETELY INTO EARLY AFTERNOON FOR MOST OF THE
AVIATION SITES. WINDS WILL GENERALLY FLOW OUT OF THE NORTHWEST
THROUGH THE PERIOD AT AROUND 5 KTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
625 AM EST Thu Dec 11 2014
...Updated Aviation Discussion...
.SHORT TERM (Now through Friday)...
Issued at 304 AM EST Thu Dec 11 2014
Clouds are again the main challenge with this forecast package.
Overcast conditions continued early this morning across southern
Indiana and central Kentucky. However, dry low level air was
punching from Quebec through Michigan into Indiana and Ohio on the
back side of cyclonic circulation over New England. By 3am the
clearing line had made it down to the I-70 corridor from
Indianapolis to Columbus. The HRRR has been doing the best job
overnight with this clearing line, with some support from 0.5km RH
progs from the GFS. These models bring the clearing line into
central and eastern parts of the LMK CWA over the course of the day,
and we`ll time it as such in the grids. West of I-65 is more of a
question mark, with models wanting to clear skies there as well but
satellite showing less clearing and more cloudiness upstream of
those areas. So, will hold on to the clouds longer in the west than
in the east.
High temperatures today should be around 40 degrees with northwest
breezes this morning becoming westerly this afternoon.
Tonight high pressure will build into the middle Mississippi and
lower Ohio Valleys. The models clear our skies out, which normally
makes sense with domes of high pressure. However, the high is
currently over the upper Mississippi Valley where it`s...cloudy.
So, there is some question whether or not we`ll really clear out
tonight. Even the wetter model solutions give us mostly clear
skies, though, so will lean on the side of fewer clouds for the
overnight hours at this time. It will be interesting to watch the
clouds to our northwest today to see if they slide southeast along
with the high or not. Big potential for a busted forecast tonight
re: sky cover.
Low temperatures tonight will depend a lot on how much cloud we end
up with. For now will stick with mid 20s. Warmer if we stay cloudy.
On Friday that high pressure system will be right on top of us,
giving us partly cloudy skies and high temperatures in the middle
and upper 40s with light winds.
.LONG TERM (Friday Night through Wednesday)...
Issued at 235 AM Thu Dec 11 2014
The upper level pattern by Friday night is expected remain highly
amplified across the CONUS, with a closed low across New England and
a deepening shortwave trough pushing into California. In between,
the blocking pattern will enhance the ridge through the central
Plains into southern Canada. At the surface, high pressure will
remain across the Mid-Mississippi and Ohio River Valleys.
Forecast challenge Friday night into Saturday is focused on cloud
cover and its impacts on temperatures. Despite very dry air above
850 mb, we`ll be dealing with some low-level moisture issues. 11.00z
guidance, particularly the NAM and GEM, suggest a strong inversion
sets up through about 925 mb, or the lowest 2500 ft, with increasing
saturation Friday night. A stratus deck would push into the region
from Upper MS River Valley based on model RH fields and would
persist through the day on Saturday. SREF probabilities for this
deck developing are currently running at or above 70 percent,
especially across the northern half of the local area. Models this
time of year struggle with low-level moisture, but given the
environmental setup, the fact that stratus is already present across
much of the central and northern Plains and the majority of the
models showing this solution, confidence is higher than average. As
such, increased cloud cover during this period and tempered the
diurnal temperature trend as well, favoring the warmer guidance for
Saturday morning lows and cooler guidance for highs.
Going into Sunday, clouds will once again be the main issue to deal
with across the Ohio Valley. Soundings differ in terms of the
strength, but all show the low level inversion remaining in place
around 925 mb, strongest along the KY/IN border and points north.
The surface high and upper level ridge axis are expected to be
directly over the region, resulting in an impressive light wind
layer /less than 10 kts through 25 kft/. If stratus is around, there
won`t be much wind to push/scour/mix it out. Again, increased cloud
cover some and lowered highs/raised lows, especially north of the KY
parkways.
By early next week, the major West Coast storm system will move
across the southern Plains and lift toward the Ohio Valley. The last
several cycles of model runs have shown high variability in the
track of this system, but the 11.00z runs seem to have come
together, bringing the system through Missouri and right across
KY/IN. Rain chances will spread in Monday, becoming likely Monday
night into Tuesday morning, then clearing out late Tuesday.
Confidence continues to increase, so POPs were adjusted higher. In
the wake of this system, a period of drier weather and seasonable
temperatures looks likely followed by the possibility of another
southern stream storm system for late next week into the following
weekend.
&&
.AVIATION (12Z TAF Update)...
Issued at 625 AM EST Thu Dec 11 2014
Clouds remain the main TAF problem. High-end MVFR ceilings
continue to dominate from the Missouri Valley through the Ohio
Valley to New England. However, dry air around 800m streaming from
eastern Canada into the Great Lakes is punching southward behind the
big East Coast storm`s circulation. While the main thrust of this
dry air will be into Ohio for the next several hours, eventually it
should make it down to LEX, and then SDF, and then BWG over the
course of the day. Attempting to time clearing of stratus is
fraught with peril, but going on satellite trends and the HRRR
(which verified very well at 11Z with the clearing line), will bring
VFR conditions into the northern TAF sites by lunch time, and to BWG
by mid afternoon. This is an hour or two later than the previous TAF
package at SDF and LEX.
The remainder of the TAF period will then be quiet.
Surface winds will come in from the northwest this morning, shifting
to the west at 5 to 10 knots this afternoon ahead of a dome of high
pressure over the middle Mississippi Valley. Winds will be nearly
calm tonight as the high moves in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........13
Long Term.........ZBT
Aviation..........13
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
524 AM CST Thu Dec 11 2014
...12z Aviation Forecast Update...
.SHORT TERM...(Today and Tonight)
Issued at 236 AM CST THU DEC 11 2014
It is a cold and dreary morning across the Missouri Ozarks with
temperatures mainly in the middle 30s. The showers associated with
an exiting shortwave are still lingering mainly for areas along
and south of I-44 this morning. Have followed closely with the
Hi-Res short term models like the RUC and WRF with the evolution
of these scattered showers through 12z. Thinking is this will move
out of southern Missouri by 12z this morning. The remainder of the
area will continue to see patchy drizzle and light fog this morning.
Cloudy skies are here to stay for a while along with drizzle and
light fog from time to time through the end of the week.
Temperatures today will not budge much with highs only in the
lower to middle 40s expected today. Low clouds...areas of drizzle
and light fog can be expected once again this evening through
early Friday morning...especially for areas along and west of
Highway 65 and on top of the Ozark Plateau.
.LONG TERM...(Friday through Wednesday)
Issued at 236 AM CST THU DEC 11 2014
Friday will be a touch milder with highs in the lower 50s and
upper 50s to near 60 by Saturday. Like mentioned before...clouds
are here to stay through the weekend. The ground temperature will
be colder than the air temperature Friday night and again on
Saturday night with milder and moist air moving over that cold
ground. The SREF probabilities for fog development is higher for
those nights. There could be some localized dense fog potential
along with more drizzle. The forecast soundings show a completely
saturated air column from the ground up to 5k feet.
The potent storm system affecting the west coast of the country
the next day or so will be affecting our weather late Sunday into
Monday. A strong and vertically stacked low pressure system will
move across the south central Plains region Sunday night. This
will bring widespread rain and possibly isolated thunder to the
area late Sunday through Monday. No severe weather is expected
with this system. Average rainfall expected will be around an inch.
Showers or drizzle will lingering on the back side of the exiting
storm system Monday afternoon through Tuesday. Temperatures will
be knocked back down to more seasonable levels early and middle of
next week with a somewhat zonal flow expected in the upper levels.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 506 AM CST THU DEC 11 2014
Low ceilings and visibilities will be a factor for pilots flying in
and out of area airports especially for tonight. For JLN and
SGF...expect mostly low end MVFR ceilings and visibilities for
today with a good signal of IFR conditions...possibly LIFR tonight.
There will be occasional mist or light drizzle.
For BBG...expected some possible LIFR ceilings this morning then
low end MVFR for today and back to IFR conditions tonight with
drizzle. There is some indication for possible LIFR visibilities
tonight with fog less than a 1sm but confidence is not high enough
to mention in TAFs at this time. Winds will be light southeasterly
about 5 knots.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Griffin
AREA FORECAST DISCUSSION
NWS BILLINGS MT
903 AM MST THU DEC 11 2014
.UPDATE...
RIDGE AXIS HAS SHIFTED EAST ALLOWING FOR INCREASED HIGH CLOUD OVER
THE REGION. GUSTY WINDS EXIST IN THE GAP AREAS PER THE LEE SIDE
TROFFING...WITH RECENT GUSTS TO 52 MPH AT A LIVINGSTON DOT SITE
AND IN ALL LIKELIHOOD SIMILAR GUSTS AT NYE. THE BACKED GRADIENT IS
SUPPORTING PURE GAP FLOW SO NOT MUCH WIND AT BIG TIMBER AND
HARLOWTON THIS MORNING. HAVE ADJUSTED WINDS AND SKY COVER TO
MATCH CURRENT CONDITIONS. TEMPS TODAY WILL BE SOMEWHAT HINDERED BY
THE CLOUD COVER BUT WE SHOULD STILL SEE WIDESPREAD 50S WITH LOWER
60S IN THE AREAS NOT AFFECTED BY COOLER DRAINAGE OR SHELTERED
MIXING...WITH 850MB TEMPS ON THE ORDER OF A BALMY +14C. JKL
&&
.SHORT TERM...VALID FOR TDY AND FRI...
DRY AND VERY WARM SOUTHWEST FLOW OF AIR WILL BE OVER THE REGION
TODAY TROUGH FRIDAY. THE ONLY WEATHER OF CONCERN WILL BE GUSTY
WINDS DEVELOPING IN THE GAP FLOW AREAS TODAY THROUGH FRIDAY. LEE-
SIDE SURFACE TROUGH DEVELOPING AS A DEEP UPPER TROUGH OF LOW
PRESSURE MOVES ONTO THE WEST COAST. THIS WILL BRING PERIODS OF
GUSTY WINDS TO LIVINGSTON AND NEAR NYE BUT THEY ARE EXPECTED TO
REMAIN BELOW ADVISORY CRITERIA. LOCAL GUIDANCE AND HRRR 80M WINDS
ALSO INDICATING WINDS TO REMAIN BELOW ADVISORY CRITERIA WITH THE
STRONGEST WINDS IN THE RANGE OF 40KTS. STRONG PUSH OF PACIFIC AIR
INTO THE AREA BOTH TODAY AND FRIDAY WITH 850 MB TEMPERATURES
PROGGED AT +14C TO +16C. THIS WILL BRING VERY MILD AFTERNOON
READINGS OF MID TO UPPER 50S ACROSS THE FORECAST AREA. WARMEST DAY
STILL LOOKS TO BE FRIDAY AS GOOD MIXING TAKING PLACE AHEAD OF A
PACIFIC COOL FRONT. TEMPERATURES SHOULD AGAIN REACH INTO THE 50S
TO LOWER 60S. THE ONLY FLY IN THE OINTMENT FOR FRIDAY HIGH
TEMPERATURES IS IF COOLER AIR BEGINS DRAINING OUT OF THE BIGHORN
BASIN AND DOWN THE CLARKS FORK VALLEY. BUFKIT SHOWING THIS A
POSSIBILITY SO ONLY TWEAKED TEMPERATURES SLIGHTLY FOR TOMORROW.
TROUGH APPROACHING THE AREA FRIDAY NIGHT AND WILL SPREAD LIGHT
RAIN AND SNOW SHOWERS INTO OUR WESTERN ZONES. MODELS STILL TAKING
STRONGEST FORCING SOUTH OF OUR AREA AND HAVE CONTINUED JUST
SCATTERED POPS FRIDAY NIGHT. RICHMOND
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MODELS HAVE BEEN CONSISTENT FROM RUN-TO-RUN OVER THE LAST DAY
WITH THE SYNOPTIC SCALE PATTERN THAT WILL AFFECT THE REGION DURING
THE EXTENDED PERIOD. ENSEMBLES DID NOTE SOME SPREAD IN THE
NORTHERN PORTION OF THE TROUGH THAT AFFECTS THE AREA THIS WEEKEND.
THERE WERE ALSO SOME DIFFERENCES IN THE FINER DETAILS OF THE
PATTERN BETWEEN THE MODELS.
PACIFIC TROUGH OFF THE W COAST THIS MORNING IN SATELLITE IMAGERY
WILL EVOLVE INTO A SPLITTING TROUGH AS IT APPROACHES THE REGION
ON SAT. THE WEAKER NORTHERN PART OF THE TROUGH WILL MOVE ACROSS
THE FORECAST AREA THROUGH SUN. THE GFS DEPICTS THIS FEATURE AS A
WEAK TROUGH...WHILE THE CANADIAN AND ECMWF SHOW A WEAK CUTOFF LOW
OVER SE ID/SW MT/W WY. THE MODELS DID AGREE IN THE EVOLUTION OF
THE SYSTEM/S MOISTURE AND COLD FRONTAL MOVEMENT THROUGH SAT NIGHT.
ON SUN...THE ECMWF WANTED TO HOLD ONTO MOISTURE OVER THE AREA
WHILE THE OTHER MODELS DRIED OUT THE AIRMASS. FOLLOWED THE
PREVIOUS FORECAST CLOSELY...GIVEN UNCERTAINTY IN THE
DETAILS...WITH LOW POPS OVERSPREADING THE PLAINS THROUGH SAT NIGHT
AND HIGHER POPS IN THE MOUNTAINS. BEGAN TO DRY OUT THE AREA ON
SUN.
ECMWF CONTINUED TO HOLD ONTO MOISTURE AND ASSOCIATED QPF THROUGH
MON NIGHT...DESPITE AN UPPER RIDGE MOVING OVER THE AREA. KEPT THE
FORECAST MAINLY DRY MON AND MON NIGHT. DIFFERENCES CONTINUED
BETWEEN MODELS ON TUE WITH ECMWF MOVING THE UPPER RIDGE OUT FASTER
THAN THE GFS. WENT DRY TUE WITH LOW MOUNTAIN POPS TUE NIGHT.
ANOTHER SPLITTING TROUGH WAS FORECAST TO MOVE INTO THE AREA WED
THROUGH THU. MOISTURE LOOKED GENERALLY CONFINED TO THE MOUNTAINS.
THE ECMWF BEGAN TO RUN COLDER THAN THE GFS BEGINNING ON MON...SO
WENT WITH A COMPROMISE FOR TEMPERATURES. SAT WILL BE WARM BEFORE
THE FRONT CROSSES THE AREA...WITH HIGHS IN THE LOWER 50S. EXPECT
HIGHS TO RUN IN THE 30S TO AROUND 40 DEGREES FOR THE REST OF THE
PERIOD. ARTHUR
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL TODAY WITH NO AVIATION HAZARDS
EXPECTED. LOW LEVEL WIND SHEAR MAY DEVELOP TONIGHT FOR AREAS FROM
BILLINGS WEST INTO THE FOOTHILLS...INCLUDING KLVM AND KBIL.
CHAMBERS
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 058 040/058 037/050 030/040 023/039 023/039 022/039
0/B 00/N 02/W 32/W 11/B 11/B 11/B
LVM 061 045/061 038/050 026/040 020/040 020/040 022/040
0/N 00/N 23/W 22/J 11/B 11/B 11/B
HDN 058 029/060 029/052 027/041 019/040 018/040 016/038
0/B 00/B 02/W 32/J 21/B 01/B 11/B
MLS 053 028/054 031/050 030/037 022/037 021/036 016/034
0/U 00/B 01/B 22/J 11/B 00/B 11/B
4BQ 059 029/060 033/054 029/039 021/039 023/039 016/037
0/U 00/B 01/B 22/W 21/B 11/B 11/B
BHK 056 032/057 032/051 027/036 020/036 020/033 014/031
0/U 00/U 00/B 22/J 22/J 00/B 01/B
SHR 061 030/063 031/052 026/038 018/039 018/038 016/038
0/U 00/B 02/W 33/J 21/B 11/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
951 AM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 942 AM CST THU DEC 11 2014
THE FOG IS SLOW TO LIFT ACROSS OUR WEST WHERE A DENSE FOG ADVISORY
REMAINS IN EFFECT. HAVE ELECTED TO EXTEND THE DENSE FOG ADVISORY
THROUGH NOON GIVEN CONTINUING REPORTS OF ONE QUARTER MILE OR LESS
VISIBILITY OVER PORTIONS OF THE ADVISORY AREA. FOG COULD LINGER
INTO THE EARLY AFTERNOON HOURS...ALTHOUGH IT LIKELY WILL NO LONGER
BE DENSE BY AFTERNOON.
THE 09Z SREF IS INDICATING NEARLY A 100 PERCENT CHANCE OF
VISIBILITY REDUCTIONS TO LESS THAN 1 MILE ACROSS MUCH OF OUR AREA
AGAIN LATER THIS EVENING INTO TONIGHT. IT IS BECOMING MORE LIKELY
THAT WE WILL SEE AN EVEN MORE WIDESPREAD AREA OF DENSE FOG THIS
EVENING INTO TONIGHT WITH VISIBILITY RANGING FROM NEAR ZERO TO ONE
QUARTER OF A MILE. A NEW DENSE FOG ADVISORY MAY EVENTUALLY BE
WARRANTED FOR LATER THIS EVENING/TONIGHT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST THU DEC 11 2014
ALOFT: THE FLOW IS COMPLEX BUT ESSENTIALLY A RIDGE AXIS EXTENDED
FROM THE DESERT SW UP INTO THE CANADIAN PRAIRIES. THIS RIDGE WILL
SLOWLY CREEP TO THE E THRU TONIGHT WHILE REMAINING JUST W OF THE
FCST AREA. BY SUNRISE FRI...A POTENT SHORTWAVE TROF WILL BE MOVING
ONSHORE INTO SRN CA. THIS WILL BE PROVIDE THE BEST CHANCE FOR
MEANINGFUL PRECIP WE HAVE SEEN HERE SINCE LATE OCT. SEE BELOW FOR
THE DETAILS.
SURFACE: HIGH PRES WAS OVER THE UPPER MS VALLEY. IT WILL REMAIN
OVER THE MS VALLEY BUT GRADUALLY SINK S THRU TONIGHT.
NOW THRU SUNRISE: CLOUDY WITH SLOWLY DECREASING VSBYS...
ESPECIALLY ALONG AND W OF HWY 283. TEMPS HOLD STEADY IN THE LOW-
MID 30S.
FOG: BELIEVE VERIFYING THE FOG ADVISORY COULD BE SHAKY IN SOME
PLACES. DENSE FOG IS MOST LIKELY WITHIN 50 MILES ON EITHER SIDE OF
THE STRATUS EDGE. AREAS E OF HWY 183 ARE PROBABLY TOO FAR INTO THE
STRATUS AND BELIEVE VSBYS SHOULD BE NO WORSE THAN MVFR /3-5 MI/.
SO THE ERN ROW OF COUNTIES WAS TRIMMED OFF THE ADVISORY FROM
BUFFALO DOWN TO OSBORNE. THE ONLY COUNTIES I AM CONFIDENT IN
LEAVING DENSE FOG ARE DAWSON/GOSPER/FURNAS. PHELPS/HARLAN/
PHILLIPS/ROOKS ARE LOW CONFIDENCE. DID EXTEND THE ADVISORY THRU 10
AM AS IT IS VERY DIFFICULT TO GET RID OF FOG/DENSE FOG BEFORE LATE
AM THIS TIME OF YEAR.
TODAY: CLOUDY TO START WITH AREAS OF FOG W OF HWY 183 THRU
MIDDAY. EXPECT SOME SLOW IMPROVEMENT AND IT SHOULD BEGIN FROM THE
W WHERE THE STRATUS IS SHALLOWER. I HAVE THE ENTIRE FCST AREA
EVENTUALLY TURNING P/CLOUDY THIS AFTERNOON AND THIS COULD BE
OVERLY OPTIMISTIC...ESPECIALLY FOR PARTS OF THE AREA E OF HWY 281
WHERE THE STRATUS COULD LINGER THE ENTIRE DAY.
DESPITE THE WARM LOOK ALOFT...A SHALLOW COOL AIR MASS WAS IN
PLACE.
850 MB TEMPS WERE VERY WARM. IF NOT FOR THE SHALLOW COOL AIR MASS
AND STRATUS...TEMPS WOULD BE IN THE 60S TODAY. THE LOW-LVLS ARE
HIGHLY INVERTED /WARMER AIR ALOFT AND COLDER NEAR THE SFC/.
USED THE NAM LOW CLOUD PRODUCT FOR THE BASIS OF THE FCST WHICH
SUPPORTS FCSTR PATTERN RECOGNITION. HRRR LOW CLOUD PRODUCT IS ALSO
SUPPORTIVE.
HIGH TEMPS ARE LOW CONFIDENCE W OF HWY 183. WHILE MIXING WILL
INITIALLY BE SUPPRESSED...THE WRN EDGE OF THE STRATUS/FOG WILL BE
ERODED AND EXPECT THAT CLOUDS WILL BREAK-UP AND DECREASE FROM THE
W. AREAS W OF HWY 183 STAND THE BEST CHANCE FOR THE GREATEST
AMOUNT OF SUN TODAY. WHERE CLEARING OCCURS WILL PLAY A SUBSTANTIAL
ROLE IN HOW WARM TEMPS GET. WHILE IT`S NOT IN THE FCST...LOW 50S
WOULD BE POSSIBLE.
TONIGHT: ANY AREAS THAT ARE P/CLOUDY OR M/CLEAR WILL CLOUD BACK
OVER. HARD TO GET A HANDLE ON FOG POTENTIAL BECAUSE IT WILL HINGE
ON WHAT IS LEFT OF THE STRATUS AT SUNSET. FOR NOW PLAYED IT
SIMILAR TO THE PREVIOUS FCST WITH FOG DEVELOPING EARLY EVENING AND
EXPANDING. DRZL WAS WITHDRAWN FROM THE FCST AS MOISTURE JUST DOES
NOT APPEAR DEEP ENOUGH IN CROSS SECTIONS/SOUNDINGS.
LOW TEMPS WILL PROBABLY OCCUR WELL BEFORE MIDNIGHT...BEFORE FOG/
STRATUS OVERTAKE THE FCST AREA. ONCE THAT OCCURS...TEMPS SHOULD
FLAT-LINE OR EVEN SLOWLY CLIMB.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 504 AM CST THU DEC 11 2014
FOR FRIDAY THROUGH SATURDAY NIGHT...THE EXPECTED DRIZZLE AND FOG
IS STILL ON...ONLY I HIT THE DRIZZLE A LITTLE HARDER IN WORDING AS
SIGNALS ARE QUITE STRONG...ESPECIALLY ON SATURDAY. FOR
TEMPERATURES...I DID BUMP LOWS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT WITH THE EXTENSIVE STRATUS EXPECTED. SATURDAY NIGHT COULD BE
QUITE WARM WITH SOME LOCATIONS IN THE CENTRAL AND SOUTHEAST NOT
DROPPING BELOW THE LOWER 50S.
FOR THE BIG SHOW...THE EXPECTED TROUGH WILL MOVE OUT OF THE
ROCKIES ON SUNDAY. TIMING AMONG NUMERICAL MODELS IS INITIALLY
SIMILAR AS THE WAVE MOVES OUT OF THE ROCKIES AND CONTINUED WARM
AIR EXISTS FOR OUR AREA AHEAD OF THE TROUGH AND THE SUBSEQUENT
DEVELOPING ASSOCIATED LOW. ALTHOUGH THERE ARE SOME FAIRLY MINOR
TRACK DIFFERENCES THROUGH THE SOUTHERN PLAINS...THE REAL POTENTIAL
FOR A BUST WILL BE HOW QUICKLY THE TROUGH AXIS MAKES ITS WAY EAST.
THE ECMWF CONTINUES TO LAG A BIT COMPARED TO OTHER NUMERICAL
MODELS AND FRANKLY...I BUY THAT. IN YEARS PAST...SIMILAR
SITUATIONS HAVE OCCURRED AND THE SLOWER SOLUTION SEEMS TO OFTEN
TIMES BE THE WAY TO GO...ESPECIALLY CONSIDERING THAT ITS THE OFT
MORE RELIABLE ECMWF FOR THE EXTENDED IN THIS CASE. THIS LEADS ME
TO BELIEVE THAT THE COLDER AIR WILL BE SLOWER TO MOVE IN AND I
HAVE BUMPED UP HIGHS A TAD ON MONDAY FROM THE PREVIOUS
FORECAST...WHICH COULD CUT INTO OUR SNOW POTENTIAL AS COLD AIR
MIGHT NOT MAKE IT HERE IN TIME TO PRODUCE AS MUCH SNOW.
HOWEVER...EVEN THE SLOWER ECMWF INDICATES THAT OUR FAR WEST/NORTH
COULD BE IN FOR SOME SNOW AS EARLY AS SUNDAY NIGHT AND CONTINUING
INTO MONDAY...ALTHOUGH THE FARTHER NORTHWEST ONE GOES...THE LESS
POTENTIAL QPF THERE WILL BE. WE ARE STILL FAR ENOUGH OUT THAT
THERE IS INCREDIBLE UNCERTAINTY HERE. I LEFT MUCH OF THE
SUPERBLEND INITIALIZED GRIDS FOR MONDAY NIGHT AND BEYOND IN TACT.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z FRI MORNING)
ISSUED AT 529 AM CST THU DEC 11 2014
TODAY: STRATUS CIGS WILL FURTHER LOWER TO 300-500 FT WITH MVFR
VSBYS. THERE IS SOME POTENTIAL FOR 1/2SM FG AT EAR. VSBY WILL
GRADUALLY IMPROVE AFTER 16Z WITH STRATUS LIFTING CIGS...BUT IT
WILL BE TOUGH TO GET RID OF THE STRATUS. CURRENT LOW CLOUD
GUIDANCE FROM THE 00Z NAM INDICATES SOME POTENTIAL FOR STRATUS
TO BREAK UP 20Z-03Z WITH A BRIEF PERIOD OF VFR POSSIBLE LATE. S
WINDS 10 KTS OR LESS. CONFIDENCE: MEDIUM
THU EVE: PROBABLY VFR TO START BUT CONDITIONS WILL BE FAVORABLE
FOR STRATUS AND/OR FOG TO REFORM. FCST GUIDANCE IS NOT HANDLING
THIS WELL. NOT SURE IF FOG OR STRATUS DOMINATES. THE MODIFIED
RICHARDSON NUMBER SUGGESTS STRATUS BUT IT WILL DEPEND ON HOW MUCH
RADIATIONAL COOLING OCCURS JUST AFTER SUNSET. S WINDS UNDER 10
KTS. CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR NEZ060-072-073-082-
083.
KS...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR KSZ005-017.
&&
$$
UPDATE...WESELY
SHORT TERM...HALBLAUB
LONG TERM...HEINLEIN
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
534 AM CST THU DEC 11 2014
.SYNOPSIS...
ISSUED AT 350 AM CST THU DEC 11 2014
H5 ANALYSIS TONIGHT HAS AN AREA OF LOW PRESSURE CENTERED OVER NEW
YORK CITY WITH A TROUGH EXTENDING SWD INTO THE WESTERN ATLANTIC.
FURTHER WEST...A POSITIVELY TILTED RIDGE EXTENDED FROM THE FOUR
CORNERS INTO WESTERN ONTARIO. WEST OF THE RIDGE...A TROUGH OF LOW
PRESSURE EXTENDED FROM THE GULF OF ALASKA SWD INTO THE EASTERN
PACIFIC. CURRENT WV IMAGERY...HAS A DECENT PLUME OF MOISTURE
EXTENDING FROM CALIFORNIA...NWD INTO WESTERN MONTANA AND THE
PRAIRIE PROVINCES OF CANADA. A SECONDARY MOISTURE TAP EXTENDED
ACROSS MEXICO INTO THE GULF OF MEXICO AND THE GULF COAST STATES.
ACROSS SOUTH DAKOTA AND NEBRASKA...DRY AIR ALOFT WAS NOTED. AT
THE SURFACE...HIGH PRESSURE REMAINED ANCHORED ACROSS THE UPPER
MIDWEST...WHILE A WEAK SURFACE TROUGH EXTENDED FROM SERN MT INTO
EASTERN WYOMING AND NERN COLORADO. LIGHT SRLY WINDS WERE PRESENT
ACROSS THE PLAINS STATES WITH LOW LEVEL MOISTURE FLOWING NORTH
INTO CENTRAL AND EASTERN NEBRASKA TONIGHT. LOW LEVEL CLOUDS AND
DENSE FOG WERE PRESENT EAST OF A LINE FROM HAYES CENTER...TO
TRYON...TO BASSETT AND NAPER. VISBYS ACROSS PORTIONS OF CENTRAL
AND SOUTHWESTERN NEBRASKA HAVE DROPPED TO UNDER A HALF A MILE
OVERNIGHT AND A DENSE FOG ADVISORY WAS IN EFFECT FOR LOCATIONS
EAST AND SOUTH OF A LINE FROM HAYES CENTER...TO SUTHERLAND...TO
DUNNING AND TAYLOR. TEMPERATURES VARIED WIDELY TONIGHT WITH
READINGS AROUND 20 IN THE EASTERN PANHANDLE...TO THE MIDDLE 30S
IN THE NORTHEASTERN FORECAST AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST THU DEC 11 2014
IN THE SHORT TERM...FOG THIS MORNING AND TONIGHT...AND ITS
IMPACTS ON HIGHS TODAY AND LOWS TONIGHT WILL BE THE MAIN
FORECASTING CONCERNS. FOR THIS MORNING...LIGHT SRLY WINDS AND A
SERIOUS LACK OF MIXING...WILL LENGTHEN THE DURATION OF FOG THIS
MORNING. A GLANCE AT THE HRRR AND NAM 12 VISBY PRODUCTS...HAVE
THIS BURNING OFF DURING THE 16Z TO 18Z TIME FRAME. FOR LOCATIONS
GENERALLY ALONG AND WEST OF A LINE FROM CURTIS...TO NORTH
PLATTE...TO BASSETT...HIGHS ARE EXPECTED TO REACH THE 50S TO
AROUND 60 IN THE PANHANDLE. FURTHER EAST HOWEVER...STRATUS WILL
PERSIST INTO THE EARLY AFTERNOON HOURS...WHICH WILL HOLD TEMPS
BACK INTO THE 40S. FORTUNATELY...WITH THE VERY DRY AIR ALOFT AND
AN EXPECTED LACK OF HIGH LEVEL CLOUDINESS TODAY...THINKING HERE
IS THAT THE FOG/STRATUS SHOULD BURN OFF FROM WEST TO EAST TDY.
ALBEIT...LATER IN THE EAST...THUS THE COOLER TEMPS. FOR
TONIGHT...BL CONDITIONS WILL MOISTEN QUICKLY AFTER SUNSET AND
WITH INCREASED BL MOISTURE PUSHING NORTH INTO CENTRAL AND EASTERN
PORTIONS OF THE FORECAST AREA OVERNIGHT...FOG POTENTIAL IS VERY
HIGH ONCE AGAIN. THE LATEST NAM BL RH PROGS AND VISBY PRODUCT IS
INDICATING A HIGH POTENTIAL FOR FOG/STRATUS DEVELOPMENT EAST OF A
LINE FROM WAUNETA...TO MULLEN...TO SPRINGVIEW. WITH GOOD
CONFIDENCE AND LITTLE CHANGE IN THE SURFACE PATTERN...IE. SURFACE
HIGH TO THE EAST AND LIGHT SRLY WINDS...HAVE INSERTED AREAS OF
FOG TONIGHT ALONG AND EAST OF THE BEFORE MENTIONED LINE. IN
ADDITION...RAISED MIN TEMPS EAST OF THIS LINE...GIVEN THE
EXPECTED MOISTURE ADVECTION. WEST OF THE LINE...CLEAR
SKIES...WILL LEAD TO SEASONAL LOWS IN THE 20S IN THE PANHANDLE
AND NORTHWESTERN SANDHILLS. LIKE TONIGHT...ON THE WESTERN
PERIPHERY OF THE FOG FIELD...VISBYS MAY DROP DOWN TO A MILE OR
LESS AND A DENSE FOG ADVZY MAY BE NEEDED. WILL ADVISE THE
ONCOMING SHIFT OF THE POSSIBLE NEED FOR THIS WITH THE AFTERNOON
FCST PACKAGE. ONE FINAL NOTE WITH RESPECT TO DRIZZLE...LOOKED
CLOSELY AT FCST SOUNDINGS FOR TONIGHT...AND THE SATURATED LAYER
IS VERY SHALLOW AT AROUND 500 TO 700 FT THICK TONIGHT. COULDN/T
FIND ANY LIFT IN THIS MOIST LAYER...SO WILL LEAVE OUT A MENTION
OF DRIZZLE FOR THE TONIGHT PERIOD.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CST THU DEC 11 2014
MAIN CONCERN WILL BE THE EFFECTS OF INCREASING MOISTURE AHEAD OF
THE TROUGH FRIDAY INTO SATURDAY...THEN DETERMINING THE TRACK OF
THE LOW PRESSURE SYSTEM ACROSS THE SOUTHERN/CENTRAL PLAINS. ALSO
TIMING THE COOLER AIR SUNDAY INTO MONDAY BEHIND THE SYSTEM.
FRIDAY WILL SEE THE UPPER LEVEL LOW COME ON SHORE ACROSS THE PAC
COAST...MEANWHILE A RIDGE BUILDS ACROSS THE PLAINS. SURFACE HIGH
SETTLES OVER THE MISS RVR VALLEY. SOUTHERLY WINDS ON THE WEST
SIDE OF THE HIGH WILL TAP GULF MOISTURE AND BRING IT NORTHWARD.
THE RICH BL MOISTURE REMAINS...ALTHOUGH IT WILL STILL BE SHALLOW
FOR THE CWA ON FRIDAY. MORNING FOG WILL ERODE FROM THE
WEST...ALTHOUGH NOT EXPECTED A CLEARING DAY FOR ALL. THIS MAKES
FOR A TRICKY FORECAST AS CLOUDS WILL LIKELY LIMIT MIXING...AND
KEEP TEMPS DOWN. HIGHS IN THE 60S ACROSS THE WEST...WITH
50S...MAYBE SOME 40S IN THE EAST.
THE TROUGH WILL PUSH ACROSS THE DESERT SOUTHWEST SATURDAY. STILL
VERY WARM ALOFT...AND MORE MOISTURE ARRIVES WITH THE SOUTHERLY
WINDS. MOIST TRANSPORT VECTORS ARE FAVORABLE TO INCREASE THE
DEPTH OF THE BL MOISTURE. ALSO SEEING A LITTLE LIFT IN THE RICH
BL...AND WILL INCLUDE SOME DRIZZLE FRIDAY NIGHT INTO SATURDAY
MORNING. THE BLANKET OF CLOUDS WILL HELP TO KEEP TEMPS ABOVE
FREEZING...SO ONLY INCLUDE DZ IN THE FORECAST NOW. THE WARM
AIR/MOIST ADVECTION CONTINUES DURING THE DAY...AND EXPECT CLOUDS
TO REMAIN THROUGH THE DAY. THIS WILL LIMIT THE MIXING AND
FORECAST HIGHS ARE BELOW GUIDANCE...WHICH COULD STILL BE TOO WARM
PENDING HOW THE WAA OVERCOMES THE CLOUDS. ALSO BUFKIT SOUNDINGS
SUGGEST SOME BETTER /ALBEIT ONLY A LITTLE/ OMEGA AS THE DEPTH OF
THE MOISTURE LAYER INCREASE. COULD BE ENOUGH FOR A LITTLE HEAVIER
DRIZZLE AND WORDED THE FORECAST FOR LIGHT RAIN IN THE EAST.
BY SUNDAY THE SYSTEM WILL PUSH ACROSS TH ROCKIES AND LIFT ACROSS
THE PLAINS. STILL SOME TIMING/TRACK ISSUES...WITH THE LATEST
ROUND OF MODELS ALL TAKING THE TRACK A LITTLE FURTHER SOUTH FROM
EARLIER RUNS. STILL HAVE ENOUGH LL MOISTURE IN PLACE WHICH WILL
BE AIDED BY SOME WRAP AROUND MOISTURE/LIFT WHICH SHOULD PRODUCE
SOME LIGHT PRECIP. ALSO GOING TO SEE TEMPS FALLING AS COOLER AIR
GETS DRAW INTO THE SYSTEM. BEST LIFT IS ALONG THE SOUTHERN BORDER
AND TO THE SOUTH AND EAST...WHICH BRINGS CONCERN TO AMOUNT OF QPF
FOR THE CWA. IT LOOKS BETTER FOR AT LEAST SOME LIGHT
PRECIP...ALTHOUGH ONLY A SLIGHT SHIFT NORTHWARD COULD PLACE SOME
MORE SIGNIFICANT QPF FOR THE CWA. ALL IN ALL...STILL NOT VERY
CONFIDENT ON AMOUNT OF QPF FOR THE CWA. ALSO MODELS SLOWED THE
COLD AIR PUSH WHICH LESSENS CONFIDENCE ON TIMING THE CHANGE OVER
FROM RAIN TO SNOW SUNDAY INTO MONDAY.
LINGERING WRAP AROUND SNOW MONDAY NIGHT ACROSS N CENTRAL...THEN
WEAK RIDGING WILL HELP TO REDUCE CLOUDS FOR MID WEEK. THE ACTIVE
PATTERN CONTINUES WITH ANOTHER TROUGH DIGGING INTO THE DESERT
SOUTHWEST BY WEDNESDAY. EYES WILL BEGIN TO MONITOR THIS AS IT
CROSSES THE SOUTHERN/CENTRAL PLAINS TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 533 AM CST THU DEC 11 2014
FOR THE KLBF TERMINAL...AREAS OF FOG WITH VISBYS DOWN TO 1/2SM ARE
LIKELY THROUGH 16Z THIS MORNING. VISBYS WILL INCREASE TO 3SM FROM
16Z TO 18Z...WITH VISBYS ABOVE 6SM THEREAFTER. VISBYS WILL BEGIN
TO DECREASE AFTER 04Z TONIGHT AND MAY DROP DOWN TO 1/2SM
OVERNIGHT. CIGS WILL BE UNDER 300 FT AGL THIS MORNING WITH CLEAR
SKIES EXPECTED THIS AFTERNOON. LOW CLOUDS ARE EXPECTED ONCE AGAIN
THIS EVENING WITH CIGS DROPPING DOWN TO 200 FT AGL AFTER 06Z
TONIGHT. FOR THE KVTN TERMINAL...EXPECT CLEAR SKIES OVER THE NEXT
24 HOURS WITH SOUTHWESTERLY WINDS OF AROUND 10 KTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ037-038-
059-070-071.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...MASEK
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
529 AM CST THU DEC 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST THU DEC 11 2014
ALOFT: THE FLOW IS COMPLEX BUT ESSENTIALLY A RIDGE AXIS EXTENDED
FROM THE DESERT SW UP INTO THE CANADIAN PRAIRIES. THIS RIDGE WILL
SLOWLY CREEP TO THE E THRU TONIGHT WHILE REMAINING JUST W OF THE
FCST AREA. BY SUNRISE FRI...A POTENT SHORTWAVE TROF WILL BE MOVING
ONSHORE INTO SRN CA. THIS WILL BE PROVIDE THE BEST CHANCE FOR
MEANINGFUL PRECIP WE HAVE SEEN HERE SINCE LATE OCT. SEE BELOW FOR
THE DETAILS.
SURFACE: HIGH PRES WAS OVER THE UPPER MS VALLEY. IT WILL REMAIN
OVER THE MS VALLEY BUT GRADUALLY SINK S THRU TONIGHT.
NOW THRU SUNRISE: CLOUDY WITH SLOWLY DECREASING VSBYS...
ESPECIALLY ALONG AND W OF HWY 283. TEMPS HOLD STEADY IN THE LOW-
MID 30S.
FOG: BELIEVE VERIFYING THE FOG ADVISORY COULD BE SHAKY IN SOME
PLACES. DENSE FOG IS MOST LIKELY WITHIN 50 MILES ON EITHER SIDE OF
THE STRATUS EDGE. AREAS E OF HWY 183 ARE PROBABLY TOO FAR INTO THE
STRATUS AND BELIEVE VSBYS SHOULD BE NO WORSE THAN MVFR /3-5 MI/.
SO THE ERN ROW OF COUNTIES WAS TRIMMED OFF THE ADVISORY FROM
BUFFALO DOWN TO OSBORNE. THE ONLY COUNTIES I AM CONFIDENT IN
LEAVING DENSE FOG ARE DAWSON/GOSPER/FURNAS. PHELPS/HARLAN/
PHILLIPS/ROOKS ARE LOW CONFIDENCE. DID EXTEND THE ADVISORY THRU 10
AM AS IT IS VERY DIFFICULT TO GET RID OF FOG/DENSE FOG BEFORE LATE
AM THIS TIME OF YEAR.
TODAY: CLOUDY TO START WITH AREAS OF FOG W OF HWY 183 THRU
MIDDAY. EXPECT SOME SLOW IMPROVEMENT AND IT SHOULD BEGIN FROM THE
W WHERE THE STRATUS IS SHALLOWER. I HAVE THE ENTIRE FCST AREA
EVENTUALLY TURNING P/CLOUDY THIS AFTERNOON AND THIS COULD BE
OVERLY OPTIMISTIC...ESPECIALLY FOR PARTS OF THE AREA E OF HWY 281
WHERE THE STRATUS COULD LINGER THE ENTIRE DAY.
DESPITE THE WARM LOOK ALOFT...A SHALLOW COOL AIR MASS WAS IN
PLACE.
850 MB TEMPS WERE VERY WARM. IF NOT FOR THE SHALLOW COOL AIR MASS
AND STRATUS...TEMPS WOULD BE IN THE 60S TODAY. THE LOW-LVLS ARE
HIGHLY INVERTED /WARMER AIR ALOFT AND COLDER NEAR THE SFC/.
USED THE NAM LOW CLOUD PRODUCT FOR THE BASIS OF THE FCST WHICH
SUPPORTS FCSTR PATTERN RECOGNITION. HRRR LOW CLOUD PRODUCT IS ALSO
SUPPORTIVE.
HIGH TEMPS ARE LOW CONFIDENCE W OF HWY 183. WHILE MIXING WILL
INITIALLY BE SUPPRESSED...THE WRN EDGE OF THE STRATUS/FOG WILL BE
ERODED AND EXPECT THAT CLOUDS WILL BREAK-UP AND DECREASE FROM THE
W. AREAS W OF HWY 183 STAND THE BEST CHANCE FOR THE GREATEST
AMOUNT OF SUN TODAY. WHERE CLEARING OCCURS WILL PLAY A SUBSTANTIAL
ROLE IN HOW WARM TEMPS GET. WHILE IT`S NOT IN THE FCST...LOW 50S
WOULD BE POSSIBLE.
TONIGHT: ANY AREAS THAT ARE P/CLOUDY OR M/CLEAR WILL CLOUD BACK
OVER. HARD TO GET A HANDLE ON FOG POTENTIAL BECAUSE IT WILL HINGE
ON WHAT IS LEFT OF THE STRATUS AT SUNSET. FOR NOW PLAYED IT
SIMILAR TO THE PREVIOUS FCST WITH FOG DEVELOPING EARLY EVENING AND
EXPANDING. DRZL WAS WITHDRAWN FROM THE FCST AS MOISTURE JUST DOES
NOT APPEAR DEEP ENOUGH IN CROSS SECTIONS/SOUNDINGS.
LOW TEMPS WILL PROBABLY OCCUR WELL BEFORE MIDNIGHT...BEFORE FOG/
STRATUS OVERTAKE THE FCST AREA. ONCE THAT OCCURS...TEMPS SHOULD
FLAT-LINE OR EVEN SLOWLY CLIMB.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 504 AM CST THU DEC 11 2014
FOR FRIDAY THROUGH SATURDAY NIGHT...THE EXPECTED DRIZZLE AND FOG
IS STILL ON...ONLY I HIT THE DRIZZLE A LITTLE HARDER IN WORDING AS
SIGNALS ARE QUITE STRONG...ESPECIALLY ON SATURDAY. FOR
TEMPERATURES...I DID BUMP LOWS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT WITH THE EXTENSIVE STRATUS EXPECTED. SATURDAY NIGHT COULD BE
QUITE WARM WITH SOME LOCATIONS IN THE CENTRAL AND SOUTHEAST NOT
DROPPING BELOW THE LOWER 50S.
FOR THE BIG SHOW...THE EXPECTED TROUGH WILL MOVE OUT OF THE
ROCKIES ON SUNDAY. TIMING AMONG NUMERICAL MODELS IS INITIALLY
SIMILAR AS THE WAVE MOVES OUT OF THE ROCKIES AND CONTINUED WARM
AIR EXISTS FOR OUR AREA AHEAD OF THE TROUGH AND THE SUBSEQUENT
DEVELOPING ASSOCIATED LOW. ALTHOUGH THERE ARE SOME FAIRLY MINOR
TRACK DIFFERENCES THROUGH THE SOUTHERN PLAINS...THE REAL POTENTIAL
FOR A BUST WILL BE HOW QUICKLY THE TROUGH AXIS MAKES ITS WAY EAST.
THE ECMWF CONTINUES TO LAG A BIT COMPARED TO OTHER NUMERICAL
MODELS AND FRANKLY...I BUY THAT. IN YEARS PAST...SIMILAR
SITUATIONS HAVE OCCURRED AND THE SLOWER SOLUTION SEEMS TO OFTEN
TIMES BE THE WAY TO GO...ESPECIALLY CONSIDERING THAT ITS THE OFT
MORE RELIABLE ECMWF FOR THE EXTENDED IN THIS CASE. THIS LEADS ME
TO BELIEVE THAT THE COLDER AIR WILL BE SLOWER TO MOVE IN AND I
HAVE BUMPED UP HIGHS A TAD ON MONDAY FROM THE PREVIOUS
FORECAST...WHICH COULD CUT INTO OUR SNOW POTENTIAL AS COLD AIR
MIGHT NOT MAKE IT HERE IN TIME TO PRODUCE AS MUCH SNOW.
HOWEVER...EVEN THE SLOWER ECMWF INDICATES THAT OUR FAR WEST/NORTH
COULD BE IN FOR SOME SNOW AS EARLY AS SUNDAY NIGHT AND CONTINUING
INTO MONDAY...ALTHOUGH THE FARTHER NORTHWEST ONE GOES...THE LESS
POTENTIAL QPF THERE WILL BE. WE ARE STILL FAR ENOUGH OUT THAT
THERE IS INCREDIBLE UNCERTAINTY HERE. I LEFT MUCH OF THE
SUPERBLEND INITIALIZED GRIDS FOR MONDAY NIGHT AND BEYOND IN TACT.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z FRI MORNING)
ISSUED AT 529 AM CST THU DEC 11 2014
TODAY: STRATUS CIGS WILL FURTHER LOWER TO 300-500 FT WITH MVFR
VSBYS. THERE IS SOME POTENTIAL FOR 1/2SM FG AT EAR. VSBY WILL
GRADUALLY IMPROVE AFTER 16Z WITH STRATUS LIFTING CIGS...BUT IT
WILL BE TOUGH TO GET RID OF THE STRATUS. CURRENT LOW CLOUD
GUIDANCE FROM THE 00Z NAM INDICATES SOME POTENTIAL FOR STRATUS
TO BREAK UP 20Z-03Z WITH A BRIEF PERIOD OF VFR POSSIBLE LATE. S
WINDS 10 KTS OR LESS. CONFIDENCE: MEDIUM
THU EVE: PROBABLY VFR TO START BUT CONDITIONS WILL BE FAVORABLE
FOR STRATUS AND/OR FOG TO REFORM. FCST GUIDANCE IS NOT HANDLING
THIS WELL. NOT SURE IF FOG OR STRATUS DOMINATES. THE MODIFIED
RICHARDSON NUMBER SUGGESTS STRATUS BUT IT WILL DEPEND ON HOW MUCH
RADIATIONAL COOLING OCCURS JUST AFTER SUNSET. S WINDS UNDER 10
KTS. CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ060-072-
073-082-083.
KS...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR KSZ005-017.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...HEINLEIN
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
505 AM CST THU DEC 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST THU DEC 11 2014
ALOFT: THE FLOW IS COMPLEX BUT ESSENTIALLY A RIDGE AXIS EXTENDED
FROM THE DESERT SW UP INTO THE CANADIAN PRAIRIES. THIS RIDGE WILL
SLOWLY CREEP TO THE E THRU TONIGHT WHILE REMAINING JUST W OF THE
FCST AREA. BY SUNRISE FRI...A POTENT SHORTWAVE TROF WILL BE MOVING
ONSHORE INTO SRN CA. THIS WILL BE PROVIDE THE BEST CHANCE FOR
MEANINGFUL PRECIP WE HAVE SEEN HERE SINCE LATE OCT. SEE BELOW FOR
THE DETAILS.
SURFACE: HIGH PRES WAS OVER THE UPPER MS VALLEY. IT WILL REMAIN
OVER THE MS VALLEY BUT GRADUALLY SINK S THRU TONIGHT.
NOW THRU SUNRISE: CLOUDY WITH SLOWLY DECREASING VSBYS...
ESPECIALLY ALONG AND W OF HWY 283. TEMPS HOLD STEADY IN THE LOW-
MID 30S.
FOG: BELIEVE VERIFYING THE FOG ADVISORY COULD BE SHAKY IN SOME
PLACES. DENSE FOG IS MOST LIKELY WITHIN 50 MILES ON EITHER SIDE OF
THE STRATUS EDGE. AREAS E OF HWY 183 ARE PROBABLY TOO FAR INTO THE
STRATUS AND BELIEVE VSBYS SHOULD BE NO WORSE THAN MVFR /3-5 MI/.
SO THE ERN ROW OF COUNTIES WAS TRIMMED OFF THE ADVISORY FROM
BUFFALO DOWN TO OSBORNE. THE ONLY COUNTIES I AM CONFIDENT IN
LEAVING DENSE FOG ARE DAWSON/GOSPER/FURNAS. PHELPS/HARLAN/
PHILLIPS/ROOKS ARE LOW CONFIDENCE. DID EXTEND THE ADVISORY THRU 10
AM AS IT IS VERY DIFFICULT TO GET RID OF FOG/DENSE FOG BEFORE LATE
AM THIS TIME OF YEAR.
TODAY: CLOUDY TO START WITH AREAS OF FOG W OF HWY 183 THRU
MIDDAY. EXPECT SOME SLOW IMPROVEMENT AND IT SHOULD BEGIN FROM THE
W WHERE THE STRATUS IS SHALLOWER. I HAVE THE ENTIRE FCST AREA
EVENTUALLY TURNING P/CLOUDY THIS AFTERNOON AND THIS COULD BE
OVERLY OPTIMISTIC...ESPECIALLY FOR PARTS OF THE AREA E OF HWY 281
WHERE THE STRATUS COULD LINGER THE ENTIRE DAY.
DESPITE THE WARM LOOK ALOFT...A SHALLOW COOL AIR MASS WAS IN
PLACE.
850 MB TEMPS WERE VERY WARM. IF NOT FOR THE SHALLOW COOL AIR MASS
AND STRATUS...TEMPS WOULD BE IN THE 60S TODAY. THE LOW-LVLS ARE
HIGHLY INVERTED /WARMER AIR ALOFT AND COLDER NEAR THE SFC/.
USED THE NAM LOW CLOUD PRODUCT FOR THE BASIS OF THE FCST WHICH
SUPPORTS FCSTR PATTERN RECOGNITION. HRRR LOW CLOUD PRODUCT IS ALSO
SUPPORTIVE.
HIGH TEMPS ARE LOW CONFIDENCE W OF HWY 183. WHILE MIXING WILL
INITIALLY BE SUPPRESSED...THE WRN EDGE OF THE STRATUS/FOG WILL BE
ERODED AND EXPECT THAT CLOUDS WILL BREAK-UP AND DECREASE FROM THE
W. AREAS W OF HWY 183 STAND THE BEST CHANCE FOR THE GREATEST
AMOUNT OF SUN TODAY. WHERE CLEARING OCCURS WILL PLAY A SUBSTANTIAL
ROLE IN HOW WARM TEMPS GET. WHILE IT`S NOT IN THE FCST...LOW 50S
WOULD BE POSSIBLE.
TONIGHT: ANY AREAS THAT ARE P/CLOUDY OR M/CLEAR WILL CLOUD BACK
OVER. HARD TO GET A HANDLE ON FOG POTENTIAL BECAUSE IT WILL HINGE
ON WHAT IS LEFT OF THE STRATUS AT SUNSET. FOR NOW PLAYED IT
SIMILAR TO THE PREVIOUS FCST WITH FOG DEVELOPING EARLY EVENING AND
EXPANDING. DRZL WAS WITHDRAWN FROM THE FCST AS MOISTURE JUST DOES
NOT APPEAR DEEP ENOUGH IN CROSS SECTIONS/SOUNDINGS.
LOW TEMPS WILL PROBABLY OCCUR WELL BEFORE MIDNIGHT...BEFORE FOG/
STRATUS OVERTAKE THE FCST AREA. ONCE THAT OCCURS...TEMPS SHOULD
FLAT-LINE OR EVEN SLOWLY CLIMB.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 504 AM CST THU DEC 11 2014
FOR FRIDAY THROUGH SATURDAY NIGHT...THE EXPECTED DRIZZLE AND FOG IS
STILL ON...ONLY I HIT THE DRIZZLE A LITTLE HARDER IN WORDING AS
SIGNALS ARE QUITE STRONG...ESPECIALLY ON SATURDAY. FOR
TEMPERATURES...I DID BUMP LOWS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT WITH THE EXTENSIVE STRATUS EXPECTED. SATURDAY NIGHT COULD BE
QUITE WARM WITH SOME LOCATIONS IN THE CENTRAL AND SOUTHEAST NOT
DROPPING BELOW THE LOWER 50S.
FOR THE BIG SHOW...THE EXPECTED TROUGH WILL MOVE OUT OF THE ROCKIES
ON SUNDAY. TIMING AMONG NUMERICAL MODELS IS INITIALLY SIMILAR AS THE
WAVE MOVES OUT OF THE ROCKIES AND CONTINUED WARM AIR EXISTS FOR OUR
AREA AHEAD OF THE TROUGH AND THE SUBSEQUENT DEVELOPING ASSOCIATED
LOW. ALTHOUGH THERE ARE SOME FAIRLY MINOR TRACK DIFFERENCES THROUGH
THE SOUTHERN PLAINS...THE REAL POTENTIAL FOR A BUST WILL BE HOW
QUICKLY THE TROUGH AXIS MAKES ITS WAY EAST. THE ECMWF CONTINUES TO
LAG A BIT COMPARED TO OTHER NUMERICAL MODELS AND FRANKLY...I BUY
THAT. IN YEARS PAST...SIMILAR SITUATIONS HAVE OCCURRED AND THE
SLOWER SOLUTION SEEMS TO OFTEN TIMES BE THE WAY TO GO...ESPECIALLY
CONSIDERING THAT ITS THE OFT MORE RELIABLE ECMWF FOR THE EXTENDED IN
THIS CASE. THIS LEADS ME TO BELIEVE THAT THE COLDER AIR WILL BE
SLOWER TO MOVE IN AND I HAVE BUMPED UP HIGHS A TAD ON MONDAY FROM
THE PREVIOUS FORECAST...WHICH COULD CUT INTO OUR SNOW POTENTIAL AS
COLD AIR MIGHT NOT MAKE IT HERE IN TIME TO PRODUCE AS MUCH SNOW.
HOWEVER...EVEN THE SLOWER ECMWF INDICATES THAT OUR FAR WEST/NORTH
COULD BE IN FOR SOME SNOW AS EARLY AS SUNDAY NIGHT AND CONTINUING
INTO MONDAY...ALTHOUGH THE FARTHER NORTHWEST ONE GOES...THE LESS
POTENTIAL QPF THERE WILL BE. WE ARE STILL FAR ENOUGH OUT THAT THERE
IS INCREDIBLE UNCERTAINTY HERE. I LEFT MUCH OF THE SUPERBLEND
INITIALIZED GRIDS FOR MONDAY NIGHT AND BEYOND IN TACT.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THU NIGHT)
ISSUED AT 1144 PM CST WED DEC 10 2014
REST OF TONIGHT: MVFR STRATUS CIGS WILL GRADUALLY DECAY TO IFR
AND EVENTUALLY LIFR. VSBYS ARE LOWER CERTAIN. SINCE STRATUS HAS
ALREADY INVADED AND ENVELOPED MUCH OF THE REGION...THE POTENTIAL
FOR IFR FOG LOOKS LOW. THIS IS SUPPORTED COMPARING THE CURRENT OBS
TO SIMILAR PAST SITUATIONS. FOR NOW MAINTAINED CONTINUITY WITH THE
PREVIOUS TAF ISSUANCE AT EAR WITH 1/4SM FG OVC002 BUT THIS MAY BE
TOO PESSIMISTIC. LIGHT S WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM
THU: LIFR STRATUS CIGS 300-500 FT AND MVFR VSBYS WILL GRADUALLY
IMPROVE AFTER 16Z...BUT IT WILL BE TOUGH TO GET RID OF THE
STRATUS. CURRENT LOW CLOUD GUIDANCE FROM THE 18Z NAM INDICATES
STRATUS SHOULD BREAK UP 20Z-22Z WITH A BRIEF PERIOD OF VFR
POSSIBLE LATE. S WINDS 10 KTS OR LESS. CONFIDENCE: MEDIUM
THU EVE: PROBABLY VFR TO START BUT CONDITIONS WILL BE FAVORABLE
FOR STRATUS TO REFORM WITH NO APPRECIABLE CHANGE IN THE WX
SITUATION. FCST GUIDANCE DOES NOT APPEAR TO BE HANDLING IT WELL
AND IS IN CONFLICT. NOT SURE IF THIS TURNS OUT A FOG OR A STRATUS
PROBLEM. THE MODIFIED RICHARDSON NUMBER SUGGESTS STRATUS BUT IT
WILL DEPEND ON HOW MUCH RADIATIONAL COOLING OCCURS JUST AFTER
SUNSET. CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ060-072-
073-082-083.
KS...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR KSZ005-017.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...HEINLEIN
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
939 AM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 936 AM CST THU DEC 11 2014
EXTENDED FOG MENTION INTO LATE MORNING AND RAISED MAXIMUM
TEMPERATURES IN THE VALLEY A DEGREE OR SO. NO OTHER CHANGES.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST THU DEC 11 2014
CLOUDS...CLOUDS...CLOUDS! SATELLITE IMAGERY INDICATES LOW-LEVEL
CLOUDS ARE RETURNING FROM THE SOUTHERN SOURCE REGION AND HAVE
OVERTAKEN ALL BUT THE FAR NORTHWEST FA. LOW-LEVEL FLOW DOES NOT
DEVIATE MUCH UNTIL A SFC TROUGH/COLD FRONT IN THE LONG TERM
PERIOD. SOME GUIDANCE INDICATES 925MB RH LOWERING DURING THE
DAYTIME HOURS...BUT 950MB RH REMAINING HIGH. THERE MAY BE SOME
BREAKS IN THE CLOUDS DURING THE DAYTIME HOURS...BUT MOSTLY CLOUDY
CONDITIONS SHOULD PREVAIL. RAP CIG GUIDANCE INDICATES CLOUDS WILL
HOLD TOUGH. OBVIOUSLY...KEEPING LOW CLOUDS IN PLACE WILL HAMPER
TEMPERATURES. THE LONG ADVERTISED WARM-UP LOOKS GOOD AT 4000-5000
FEET ABOVE THE SURFACE...BUT NOT WHERE MOST PEOPLE ACTUALLY LIVE.
THUS...SIGNIFICANTLY LOWERED MAX TEMPS. FOG ALSO
POSSIBLE...ALTHOUGH DO NOT ANTICIPATE DENSE FOG AS SFC WINDS
REMAIN AT LEAST 10 KNOTS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 402 AM CST THU DEC 11 2014
FRIDAY NIGHT-SATURDAY NIGHT...SURFACE TROUGH APPROACHES AND MOVES
THROUGH THE REGION. THIS WILL INCREASE LOW LEVEL MOISTURE EVEN
FURTHER (SFC DEWPOINTS INTO THE MID-UPPER 30S...POSSIBLY 40F). LOW
CLOUDS LIKELY WILL REMAIN...WITH DRIZZLE BECOMING POSSIBLE WITH
WEAK LOW LEVEL LIFT AHEAD OF THE SFC TROUGH. AGAIN...LOWERED MAX
TEMP FOR SATURDAY CONSIDERING EXPECTED LOW CLOUDS...ALTHOUGH NOT AS
MUCH AS PREVIOUS DAYS CONSIDERING THE HIGHER DEWPOINT VALUES.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH REMAINS OVER THE EASTERN
PACIFIC WHILE THE LONG WAVE RIDGE WAS OVER THE NORTHERN PLAINS.
PATTERN DE AMPLIFIES A BIT. LONG WAVE RIDGE RE DEVELOPS OVER THE
ROCKIES AND SHIFTS INTO THE HIGH PLAINS BY THE END OF THE PERIOD.
THE GFS WAS FASTER THAN THE ECMWF THROUGH THE PERIOD. BOTH GFS AND
ECMWF WERE TRENDING SLIGHTLY SLOWER OVER THE LAST COUPLE MODEL
RUNS. WILL PREFER THE ECMWF.
TROUGH OVER THE EASTERN PACIFIC WILL MOVE ACROSS SOUTHERN CANADA BY
SUN/MON AND BRING COOLER AIR T THE AREA.
LITTLE CHANGE TO TEMPS. A DEGREE OR SO HIGHER FOR SUN AND MON AND A
DEGREE LOWER FOR TUE. NO CHANGE FOR WED COMPARED TO YESTERDAYS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 625 AM CST THU DEC 11 2014
LIFR/IFR CIGS LIKELY THROUGH THE PERIOD. CONFIDENCE IS RAPIDLY
INCREASING THAT THESE LOW CIGS WILL CONTINUE FOR THE FORESEEABLE
FUTURE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
625 AM CST THU DEC 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST THU DEC 11 2014
CLOUDS...CLOUDS...CLOUDS! SATELLITE IMAGERY INDICATES LOW-LEVEL
CLOUDS ARE RETURNING FROM THE SOUTHERN SOURCE REGION AND HAVE
OVERTAKEN ALL BUT THE FAR NORTHWEST FA. LOW-LEVEL FLOW DOES NOT
DEVIATE MUCH UNTIL A SFC TROUGH/COLD FRONT IN THE LONG TERM
PERIOD. SOME GUIDANCE INDICATES 925MB RH LOWERING DURING THE
DAYTIME HOURS...BUT 950MB RH REMAINING HIGH. THERE MAY BE SOME
BREAKS IN THE CLOUDS DURING THE DAYTIME HOURS...BUT MOSTLY CLOUDY
CONDITIONS SHOULD PREVAIL. RAP CIG GUIDANCE INDICATES CLOUDS WILL
HOLD TOUGH. OBVIOUSLY...KEEPING LOW CLOUDS IN PLACE WILL HAMPER
TEMPERATURES. THE LONG ADVERTISED WARM-UP LOOKS GOOD AT 4000-5000
FEET ABOVE THE SURFACE...BUT NOT WHERE MOST PEOPLE ACTUALLY LIVE.
THUS...SIGNIFICANTLY LOWERED MAX TEMPS. FOG ALSO
POSSIBLE...ALTHOUGH DO NOT ANTICIPATE DENSE FOG AS SFC WINDS
REMAIN AT LEAST 10 KNOTS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 402 AM CST THU DEC 11 2014
FRIDAY NIGHT-SATURDAY NIGHT...SURFACE TROUGH APPROACHES AND MOVES
THROUGH THE REGION. THIS WILL INCREASE LOW LEVEL MOISTURE EVEN
FURTHER (SFC DEWPOINTS INTO THE MID-UPPER 30S...POSSIBLY 40F). LOW
CLOUDS LIKELY WILL REMAIN...WITH DRIZZLE BECOMING POSSIBLE WITH
WEAK LOW LEVEL LIFT AHEAD OF THE SFC TROUGH. AGAIN...LOWERED MAX
TEMP FOR SATURDAY CONSIDERING EXPECTED LOW CLOUDS...ALTHOUGH NOT AS
MUCH AS PREVIOUS DAYS CONSIDERING THE HIGHER DEWPOINT VALUES.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH REMAINS OVER THE EASTERN
PACIFIC WHILE THE LONG WAVE RIDGE WAS OVER THE NORTHERN PLAINS.
PATTERN DE AMPLIFIES A BIT. LONG WAVE RIDGE RE DEVELOPS OVER THE
ROCKIES AND SHIFTS INTO THE HIGH PLAINS BY THE END OF THE PERIOD.
THE GFS WAS FASTER THAN THE ECMWF THROUGH THE PERIOD. BOTH GFS AND
ECMWF WERE TRENDING SLIGHTLY SLOWER OVER THE LAST COUPLE MODEL
RUNS. WILL PREFER THE ECMWF.
TROUGH OVER THE EASTERN PACIFIC WILL MOVE ACROSS SOUTHERN CANADA BY
SUN/MON AND BRING COOLER AIR T THE AREA.
LITTLE CHANGE TO TEMPS. A DEGREE OR SO HIGHER FOR SUN AND MON AND A
DEGREE LOWER FOR TUE. NO CHANGE FOR WED COMPARED TO YESTERDAYS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 625 AM CST THU DEC 11 2014
LIFR/IFR CIGS LIKELY THROUGH THE PERIOD. CONFIDENCE IS RAPIDLY
INCREASING THAT THESE LOW CIGS WILL CONTINUE FOR THE FORESEEABLE
FUTURE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1010 AM EST THU DEC 11 2014
.SYNOPSIS...
HIGH PRESSURE AND A DRY AIRMASS WILL START TO MOVE IN FROM THE
WEST TODAY. DRY WEATHER WILL CONTINUE THROUGH THE WEEKEND AS THE
HIGH TRAVELS EASTWARD ACROSS THE OHIO VALLEY. LOW PRESSURE IS
FORECAST TO PROVIDE A CHANCE OF RAIN NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DRY AIR WRAPPING IN FROM THE NORTH AROUND THE EAST COAST STORM
BROUGHT CLEARING SKIES TO THE REGION OVERNIGHT. THERE IS STILL
ABUNDANT LOW LEVEL MOISTURE OVER MUCH OF INDIANA HOWEVER. WHAT WILL
HAPPEN TO THAT MOISTURE IS THE BIG QUESTION. FLOW AROUND THE
BUILDING HIGH PRESSURE SHOULD KEEP THE BULK OF THAT MOISTURE TO
THE WEST...BUT SOME SCATTERED CU COULD TRY AND DEVELOP DURING THE
AFTERNOON.
DESPITE THE SUNSHINE TODAY...TEMPERATURES WILL BE SLIGHTLY BELOW
NORMAL...WITH TEMPERATURES PUSHING INTO THE MID TO UPPER 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
COASTAL SYSTEM WILL GRADUALLY MOVE EAST WHILE A RIDGE BUILDS INTO
THE OHIO VALLEY. THIS PATTERN WILL RESULT IN CONTINUING DRY
WEATHER. MAINLY SUNNY SKIES ARE EXPECTED FOR FRIDAY UNDER
SUBSIDENCE. MODELS INDICATE LIMITED MOISTURE ADVECTION AROUND THE
CREST OF THE RIDGE BY SATURDAY AFTERNOON...WHICH MAY CAUSE CLOUDS
TO INCREASE.
TEMPERATURES WILL SHOW A SLIGHT WARMING TREND AS THE AIRMASS HEATS
UP GRADUALLY. HIGHS WILL RANGE FROM THE MID 30S TO LOWER 40S ON
FRIDAY...INCREASING TO THE LOW TO MID 40S ON SATURDAY. SPLIT THE
DIFFERENCE BETWEEN THE COOLER MET AND WARMER MAV MOS GUIDANCE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WELL-DEFINED TROUGH-RIDGE-TROUGH SETUP WILL BE IN PLACE ACROSS
THE COUNTRY...AND WITH THE RIDGE EXPECTED TO MOVE SLOWLY THROUGH
THE OHIO VALLEY...DRY CONDITIONS ARE FAVORED THROUGH THE WEEKEND.
AS THE NEXT TROUGH APPROACHES...CHANCES FOR PRECIPITATION WILL
INCREASE MONDAY INTO TUESDAY.
THIS PATTERN ALSO FAVORS WARM ADVECTION...WITH GRADUALLY WARMING
TEMPERATURES EXPECTED THROUGH AT LEAST MONDAY. HIGHS ON SUNDAY AND
MONDAY WILL LIKELY BE AT LEAST 5 DEGREES ABOVE NORMAL.
AS THE NEW WEEK BEGINS...ATTENTION WILL FOCUS ON THE TROUGH
INITIALLY OVER THE WESTERN SECTIONS OF THE COUNTRY. AS A JET STREAK
AROUND THE BASE OF THE TROUGH MOVES ASHORE...EVENTUALLY A SURFACE
LOW IS FORECAST TO DEVELOP...ASSOCIATED WITH A MID-LEVEL LOW MOVING
OUT OF THE FOUR CORNERS. HOWEVER...THE TIMING AND STRENGTH OF THIS
SYSTEM REMAINS A SOURCE OF INCONSISTENCY IN THE MODELS...WHICH IS
NOT ESPECIALLY SURPRISING GIVEN THE VARIABLES GOING INTO ITS
DEVELOPMENT. GFS ENSEMBLE MEMBERS CONTINUE TO SHOW SIGNIFICANT
SPREAD IN BOTH THE DEVELOPMENT OF THE MID-LEVEL LOW AND THE
BREAKDOWN OF THE RIDGE OVER THE MISSISSIPPI AND OHIO VALLEY REGIONS.
IN TERMS OF THE OPERATIONAL MODELS...THE OVERALL TREND HAS BEEN FOR
A TRACK FURTHER NORTH THAN IN PREVIOUS RUNS...FAVORING A SLIGHTLY
WETTER SOLUTION FOR THE OHIO VALLEY. THE 12Z GFS IS THE FASTEST OF
THE MAIN SOLUTIONS...WITH THE 12Z ECMWF COMING IN SLOWER...AND THE
12Z GEM A FAIR COMPROMISE BETWEEN THE TWO. POPS WERE INCREASED A
LITTLE BIT THROUGH THIS PERIOD (MAINLY MONDAY NIGHT AND EARLY
TUESDAY). IN ADDITION...THE NORTHWARD TREND AT LEAST INTRODUCES THE
QUESTION OF WHETHER OR NOT SOME ELEVATED INSTABILITY COULD
DEVELOP...THOUGH THUNDER WAS NOT ADDED TO THE FORECAST BASED ON THE
MODEL RUNS TODAY.
DEPENDING ON THE EXACT TIMING OF THE SYSTEM...ADVECTION IN THE
VICINITY OF THE SURFACE LOW COULD KEEP TEMPERATURES SOMEWHAT WARM ON
MONDAY NIGHT AND POSSIBLY INTO TUESDAY. HOWEVER...ONCE THE LOW
PASSES...COLD ADVECTION ON THE BACK SIDE WILL PROVIDE FOR A RETURN
TO COOLER CONDITIONS FOR THE MIDDLE OF THE WEEK.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
LARGE MID LEVEL LOW MEANDERS OVER NEW ENGLAND WITH RIDGE BUILDING
OVER THE NATIONS MID SECTION THRU THE TAF FCST PERIOD. THIS PLACES
THE OHIO VALLEY IN NORTHERLY FLOW. LATEST SATL IMGRY SHOWS A WEDGE
OF CLEARING PUSHING SOUTH THRU OHIO. LATEST RAP 925 MB HAS GOOD
HANDLE ON THIS CLEARING WEDGE. EXPECT MAINLY VFR CONDITIONS EARLY
THIS MORNING WITH THE EXCEPTION OF MVFR FOG AT KDAY. THIS FOG WILL
QUICKLY IMPROVE. RAP SHOWS LOW CLOUDS OVER INDIANA COMING BACK
INTO SW OHIO THIS AFTN. HAVE A TEMPO GROUP MENTIONING MVFR CIGS AT
KCVG/KLUK/KDAY AND KILN. SFC HIGH PRESSURE OVER THE UPR MS VLY TO
BUILD SOUTH EAST NOSING INTO OHIO LATER TODAY INTO TONIGHT. THIS
HIGH WILL PROVIDE MAINLY CLEAR SKY CONDITIONS OVERNIGHT.
NORTHWEST WINDS WILL UP TO 12 KTS WILL BECOME WESTERLY AT 10 KTS
OR LESS OVERNIGHT.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO/SITES
NEAR TERM...SITES
SHORT TERM...CONIGLIO
LONG TERM...HATZOS
AVIATION...AR
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
645 AM EST THU DEC 11 2014
.SYNOPSIS...
HIGH PRESSURE AND A DRY AIRMASS WILL START TO MOVE IN FROM THE
WEST TODAY. DRY WEATHER WILL CONTINUE THROUGH THE WEEKEND AS THE
HIGH TRAVELS EASTWARD ACROSS THE OHIO VALLEY. LOW PRESSURE IS
FORECAST TO PROVIDE A CHANCE OF RAIN NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AREA IS UNDER A NORTHWEST FLOW BETWEEN A COASTAL LOW AND A
MISSISSIPPI VALLEY HIGH. SATELLITE IMAGERY SHOWS A CLEARING TREND
ARRIVING WITH THE LOW LEVEL FLOW. ACCORDING TO MODELS...CLOUDS
WILL DISSIPATE ACROSS THE ENTIRE AREA...GIVING MOSTLY SUNNY SKIES
TODAY. COLD ADVECTION OFFSET BY LOW ANGLE INSOLATION WILL YIELD
HIGH TEMPERATURES IN THE MID TO UPPER 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
COASTAL SYSTEM WILL GRADUALLY MOVE EAST WHILE A RIDGE BUILDS INTO
THE OHIO VALLEY. THIS PATTERN WILL RESULT IN CONTINUING DRY
WEATHER. MAINLY SUNNY SKIES ARE EXPECTED FOR FRIDAY UNDER
SUBSIDENCE. MODELS INDICATE LIMITED MOISTURE ADVECTION AROUND THE
CREST OF THE RIDGE BY SATURDAY AFTERNOON...WHICH MAY CAUSE CLOUDS
TO INCREASE.
TEMPERATURES WILL SHOW A SLIGHT WARMING TREND AS THE AIRMASS HEATS
UP GRADUALLY. HIGHS WILL RANGE FROM THE MID 30S TO LOWER 40S ON
FRIDAY...INCREASING TO THE LOW TO MID 40S ON SATURDAY. SPLIT THE
DIFFERENCE BETWEEN THE COOLER MET AND WARMER MAV MOS GUIDANCE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WELL-DEFINED TROUGH-RIDGE-TROUGH SETUP WILL BE IN PLACE ACROSS
THE COUNTRY...AND WITH THE RIDGE EXPECTED TO MOVE SLOWLY THROUGH
THE OHIO VALLEY...DRY CONDITIONS ARE FAVORED THROUGH THE WEEKEND.
AS THE NEXT TROUGH APPROACHES...CHANCES FOR PRECIPITATION WILL
INCREASE MONDAY INTO TUESDAY.
THIS PATTERN ALSO FAVORS WARM ADVECTION...WITH GRADUALLY WARMING
TEMPERATURES EXPECTED THROUGH AT LEAST MONDAY. HIGHS ON SUNDAY AND
MONDAY WILL LIKELY BE AT LEAST 5 DEGREES ABOVE NORMAL.
AS THE NEW WEEK BEGINS...ATTENTION WILL FOCUS ON THE TROUGH
INITIALLY OVER THE WESTERN SECTIONS OF THE COUNTRY. AS A JET STREAK
AROUND THE BASE OF THE TROUGH MOVES ASHORE...EVENTUALLY A SURFACE
LOW IS FORECAST TO DEVELOP...ASSOCIATED WITH A MID-LEVEL LOW MOVING
OUT OF THE FOUR CORNERS. HOWEVER...THE TIMING AND STRENGTH OF THIS
SYSTEM REMAINS A SOURCE OF INCONSISTENCY IN THE MODELS...WHICH IS
NOT ESPECIALLY SURPRISING GIVEN THE VARIABLES GOING INTO ITS
DEVELOPMENT. GFS ENSEMBLE MEMBERS CONTINUE TO SHOW SIGNIFICANT
SPREAD IN BOTH THE DEVELOPMENT OF THE MID-LEVEL LOW AND THE
BREAKDOWN OF THE RIDGE OVER THE MISSISSIPPI AND OHIO VALLEY REGIONS.
IN TERMS OF THE OPERATIONAL MODELS...THE OVERALL TREND HAS BEEN FOR
A TRACK FURTHER NORTH THAN IN PREVIOUS RUNS...FAVORING A SLIGHTLY
WETTER SOLUTION FOR THE OHIO VALLEY. THE 12Z GFS IS THE FASTEST OF
THE MAIN SOLUTIONS...WITH THE 12Z ECMWF COMING IN SLOWER...AND THE
12Z GEM A FAIR COMPROMISE BETWEEN THE TWO. POPS WERE INCREASED A
LITTLE BIT THROUGH THIS PERIOD (MAINLY MONDAY NIGHT AND EARLY
TUESDAY). IN ADDITION...THE NORTHWARD TREND AT LEAST INTRODUCES THE
QUESTION OF WHETHER OR NOT SOME ELEVATED INSTABILITY COULD
DEVELOP...THOUGH THUNDER WAS NOT ADDED TO THE FORECAST BASED ON THE
MODEL RUNS TODAY.
DEPENDING ON THE EXACT TIMING OF THE SYSTEM...ADVECTION IN THE
VICINITY OF THE SURFACE LOW COULD KEEP TEMPERATURES SOMEWHAT WARM ON
MONDAY NIGHT AND POSSIBLY INTO TUESDAY. HOWEVER...ONCE THE LOW
PASSES...COLD ADVECTION ON THE BACK SIDE WILL PROVIDE FOR A RETURN
TO COOLER CONDITIONS FOR THE MIDDLE OF THE WEEK.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
LARGE MID LEVEL LOW MEANDERS OVER NEW ENGLAND WITH RIDGE BUILDING
OVER THE NATIONS MID SECTION THRU THE TAF FCST PERIOD. THIS PLACES
THE OHIO VALLEY IN NORTHERLY FLOW. LATEST SATL IMGRY SHOWS A WEDGE
OF CLEARING PUSHING SOUTH THRU OHIO. LATEST RAP 925 MB HAS GOOD
HANDLE ON THIS CLEARING WEDGE. EXPECT MAINLY VFR CONDITIONS EARLY
THIS MORNING WITH THE EXCEPTION OF MVFR FOG AT KDAY. THIS FOG WILL
QUICKLY IMPROVE. RAP SHOWS LOW CLOUDS OVER INDIANA COMING BACK
INTO SW OHIO THIS AFTN. HAVE A TEMPO GROUP MENTIONING MVFR CIGS AT
KCVG/KLUK/KDAY AND KILN. SFC HIGH PRESSURE OVER THE UPR MS VLY TO
BUILD SOUTH EAST NOSING INTO OHIO LATER TODAY INTO TONIGHT. THIS
HIGH WILL PROVIDE MAINLY CLEAR SKY CONDITIONS OVERNIGHT.
NORTHWEST WINDS WILL UP TO 12 KTS WILL BECOME WESTERLY AT 10 KTS
OR LESS OVERNIGHT.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO
SHORT TERM...CONIGLIO
LONG TERM...HATZOS
AVIATION...AR
AREA FORECAST DISCUSSION
NWS MEDFORD OR
408 AM PST THU DEC 11 2014
.SHORT TERM...A STRONG LOW PRESSURE IS LOCATED ABOUT 250 MILES
OFF THE OREGON CALIFORNIA COAST BORDER. THIS LOW PRESSURE IS
FORECAST TO APPROACH THE SOUTHERN OREGON COAST THIS MORNING AND
MOVE NORTH ALONG THE OREGON COAST DURING THE AFTERNOON. THIS LOW
IS FORECAST TO BE AROUND 975 TO 980 MB AS IT NEARS THE SOUTHERN
OREGON COAST TODAY. IT WILL BRING A STRONG PRESSURE GRADIENT
AS WELL AS STRONG LOW AND MID LEVEL JETS INTO THE AREA...RESULTING
IN VERY STRONG GUSTY WINDS DEVELOPING OVER MUCH OF THE AREA THIS
MORNING INTO THIS AFTERNOON.
WINDS HAVE BEGUN TO INCREASE EARLY THIS MORNING WITH GUSTY SOUTH
TO SOUTHEAST WINDS DEVELOPING ALONG THE COAST, OVER THE MOUNTAINS
AND INLAND INTO SOME VALLEY LOCATIONS, INCLUDING THE SHASTA AND
ROGUE VALLEYS. OBSERVATIONS ALSO SHOW GALE FORCE WINDS DEVELOPING
IN THE SOUTHERN COASTAL WATERS EARLY THIS MORNING. WINDS ARE
EXPECTED TO RISE TO STORM FORCE IN THE COASTAL WATERS WITH AREAS
OF HIGH WINDS EXPECTED ALONG THE COAST AND INLAND.
CURRENT MODELS ARE IN GOOD AGREEMENT WITH THE TIMING AND TRACK OF
THE LOW AND SHOW THIS LOW APPROACHING WITHIN 100 NM OF THE COAST,
CENTERED OFF CAPE BLANCO BY LATE THIS MORNING. THEN SHIFTING
NORTH DURING THE AFTERNOON ALONG THE CENTRAL OREGON COAST. THE
NAM REMAINS SLIGHTLY SLOWER THAN THE OTHER MODELS WITH THE TRACK
OF THIS LOW AND HAVE LEANED TOWARDS A COMBINATION OF THE GFS AND
ECMWF AS WELL THE HIGH RESOLUTION NMW AND RAP MODELS. THESE
MODELS BRING A SOUTH 70 TO 80 KT 925 MB JET ALONG THE COAST WITH
THE PASSAGE OF THE LOW. THIS WILL ALLOW HIGH WINDS TO DEVELOP IN
COASTAL AREAS, INITIALLY ALONG THE SOUTH COAST EARLY THIS
MORNING, THEN SPREADING ALONG THE ENTIRE SOUTHERN OREGON COAST IN
THE MID TO LATE MORNING AND CONTINUING INTO THE AFTERNOON. PEAK
WINDS ALONG THE COAST ARE EXPECTED TO BE AROUND 40 TO 55 MPH WITH
FREQUENT GUSTS OF 60 TO 70 MPH AND OCCASIONAL GUSTS TO 80 MPH OR
POSSIBLY HIGHER. WINDS ARE EXPECTED TO DECREASE FROM SOUTH TO
NORTH IN THE MID TO LATE AFTERNOON ALONG THE COAST.
INLAND AREAS WILL ALSO SEE STRONG GUSTY WINDS THIS MORNING INTO
THIS AFTERNOON AS A MID LEVEL JET OF AROUND 80 KT MOVES OVER THIS
AREA THIS MORNING INTO THIS AFTERNOON. STRONGEST WINDS ARE
EXPECTED IN THE SHASTA VALLEY, SOUTHERN ROGUE VALLEY, OVER THE
CASCADES AND SISKIYOUS, AND EAST OF THE CASCADES. THESE AREAS ARE
EXPECTED TO EXPERIENCE VERY STRONG, AND POTENTIALLY DAMAGING,
WINDS GUSTING TO AROUND 60 TO 70 MPH AND LOCALLY HIGHER. ALTHOUGH
THESE AREAS WILL SEE THE STRONGEST WINDS AND GREATEST IMPACTS,
EXPECT MOST THE AREA TO SEE VERY GUSTY WINDS TODAY. WIND WARNINGS
AND WIND ADVISORIES ARE IN PLACE THROUGH THIS AFTERNOON ACROSS
MOST THE AREA.
IN ADDITION TO STRONG GUSTY WINDS, MODERATE TO LOCALLY HEAVY RAIN
WILL MOVE INTO THE AREA WITH THIS LOW PASSAGE. THIS MAY BRING THE
POTENTIAL FOR FLOODING IMPACTS TO WESTERN PORTIONS OF THE AREA.
AN AREAL FLOOD WATCH REMAINS IN EFFECT FOR COASTAL AREAS AND A
FLASH FLOOD WATCH IS IN EFFECT FOR THE WILDFIRE BURN SCARS IN
WESTERN SISKIYOU. MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED THIS
MORNING ALONG THE COAST, ESPECIALLY IN CURRY COUNTY. THIS RAIN
COMBINED WITH RAINFALL FROM YESTERDAYS STORM, MAY ALLOW FOR SMALL
STREAM OR LOCALIZED URBAN FLOODING ALONG THE COAST. IN WESTERN
SISKIYOU COUNTY, MODERATE TO HEAVY RAINFALL IS ALSO EXPECTED THIS
MORNING AND MAY BRING THE POTENTIAL FOR FLASH FLOODING IN THE
WILDFIRE BURN SCAR AREAS.
THIS EVENING AND TONIGHT, WINDS ARE EXPECTED TO DIMINISH OVER THE
AREA AS THE LOW SHIFTS NORTH. AN UPPER TROUGH WILL PUSH INTO THE
AREA FROM THE WEST THIS EVENING INTO FRIDAY. THIS WILL BRING A
COOL AND SHOWERY AIR MASS TO THE AREA THROUGH FRIDAY.
SNOW LEVELS ARE EXPECTED TO LOWER FROM 7000 FEET THIS MORNING TO
AROUND 6000 FT THIS AFTERNOON AS COLD AIR MOVES INTO THE AREA
BEHIND THE LOW. THEN AS AN UPPER TROUGH PUSHES INLAND TONIGHT
EXPECT SNOW LEVELS TO LOWER DOWN TO 5000 FT...WITH SNOW LEVELS OF
AROUND 4500 TO 5000 FT ON FRIDAY. THESE LOWER SNOW LEVELS
COMBINED WITH SHOWER ACTIVITY WILL BRING SOME LIGHT SNOW
ACCUMULATIONS TO HIGHER ELEVATIONS. UPPER MOUNTAINS, ABOVE 7000
FT ELEVATION, WILL SEE SIGNIFICANT SNOW AMOUNTS TODAY INTO
TONIGHT.
THE COLD AIR ALOFT ASSOCIATED WITH THE LOW WILL ALSO BRING A
CHANCE OF ISOLATED THUNDERSTORMS TO THE COAST AND COASTAL WATERS
TODAY. THEN AS THE UPPER TROUGH MOVES INTO THE AREA, EXPECT THIS
SLIGHT CHANCE FOR THUNDERSTORMS TO EXTEND INLAND TONIGHT INTO
FRIDAY INTO AREAS WEST OF THE CASCADES.
&&
.AVIATION...BASED ON THE 11/06Z TAF CYCLE...WINDS HAVE TEMPORARILY
DECREASED THIS EVENING, BUT WILL INCREASE AGAIN TONIGHT AS STRONG
LOW PRESSURE MOVES NEAR THE COAST. MODERATE TO STRONG WINDS ARE
GOING TO BE THE MAIN CONCERN FOR ALL TERMINALS THURSDAY WITH WIND
SPEED SHEAR. IT WILL BE A CLOSE CALL FOR WIND SPEED SHEAR AT KLAMATH
FALLS AND LATER SHIFTS WILL WANT TO TAKE ANOTHER LOOK AT THIS. VFR
CIGS ARE EXPECTED, BUT LOCAL MVFR CIGS/VSBYS ARE POSSIBLE THURSDAY
IN HEAVIER RAIN WITH HIGHER TERRAIN OBSCURED. -PETRUCELLI
&&
.MARINE...UPDATED 200 AM PST THU DEC 11 2014...WINDS WILL INCREASE
THROUGH THIS MORNING AS A SURFACE LOW DEEPENS OFFSHORE, THEN MOVES
NORTH THROUGH THE COASTAL WATERS THIS AFTERNOON. EXPECT ANOTHER
ROUND OF STORM FORCE WINDS, WITH HURRICANE FORCE GUSTS
POSSIBLE, ESPECIALLY IN THE VICINITY OF CAPE BLANCO.
MEANWHILE...HEAVY LONG PERIOD WEST SWELL WILL COMBINE WITH STRONG
SOUTHERLY CHOP TO PRODUCE VERY STEEP AND HAZARDOUS SEAS THROUGH THIS
AFTERNOON. COMBINED SEAS WILL BUILD TO HEIGHTS IN EXCESS OF 25 FEET,
WITH BREAKING WAVES OF OVER 30 FEET EXPECTED NEAR SHORE,
SHOALS, AND OTHER SHALLOW WATER AREAS.
THIS WILL BE A VERY STRONG STORM. ALL MARITIME AND COASTAL INTERESTS
SHOULD TAKE ALL PRECAUTIONS NECESSARY TO PRESERVE LIFE AND
PROPERTY...AS SIGNIFICANT DAMAGE IS POSSIBLE TO UNSECURED AND
EXPOSED EQUIPMENT AND INFRASTRUCTURE. IT IS STRONGLY RECOMMENDED
THAT ALL VESSELS REMAIN IN SAFE HARBOR UNTIL CONDITIONS IMPROVE THIS
EVENING.
BEYOND THURSDAY...WINDS WILL DIMINISH...BUT UNSETTLED WEATHER WILL
CONTINUE THROUGH THE NEXT WEEK. SEAS WILL GRADUALLY SUBSIDE THROUGH
THE NEXT SEVERAL DAYS, REMAINING ABOVE SMALL CRAFT CRITERIA THROUGH
AT LEAST SATURDAY. EXPECT ANOTHER ROUND OF STRONG WINDS AND HEAVY
SEAS AS THE NEXT FRONTAL SYSTEM ENTERS THE COASTAL WATERS THIS
WEEKEND. THERE IS ALSO THE POTENTIAL FOR HEAVY LONG PERIOD SWELL TO
RETURN TO THE AREA EARLY NEXT WEEK. -BPN
&&
.PREV LONG TERM DISCUSSION... /ISSUED 252 PM PST WED DEC 10 2014/
LONG TERM...FRIDAY THROUGH WEDNESDAY...ON FRIDAY A BROAD UPPER
TROUGH WILL REMAIN OVER THE NORTHWEST WITH SCATTERED TO NUMEROUS
SHOWERS AND SNOW LEVELS BETWEEN 4500-5000 FEET. COULD SEE UP TO A
FEW INCHES OF ACCUMULATION OVER THE HIGHER TERRAIN EAST OF THE
CASCADES. THERE IS SOME UNCERTAINTY WITH POTENTIALLY HIGHER SNOW
AMOUNTS AS A SURFACE LOW SHOULD TRACK SOUTH TO NORTH INTO SOUTHEAST
OREGON WITH POTENTIAL HEAVIER AMOUNTS OVER LAKE COUNTY. COULD NEED
TO BUMP TOTALS THERE IN UPCOMING FORECASTS. FRIDAY NIGHT THROUGH
SATURDAY THINGS WILL SETTLE DOWN CONSIDERABLY WITH SOME MORNING
VALLEY FOG DEVELOPING IN AREAS UNDER SHORTWAVE RIDGING. BOTH THE
EURO AND GFS SOLUTIONS ARE BRINGING IN ANOTHER UPPER TROUGH TO THE
COAST LATER SUNDAY THROUGH MONDAY WITH SHOWER CHANCES INCREASING
MAINLY ACROSS THE COAST AND NORTHWEST CALIFORNIA. THIS TROUGH SHOULD
TRAVERSE THE REGION MONDAY NIGHT THROUGH TUESDAY WITH SHOWERS
BECOMING MORE NUMEROUS. ADDITIONAL SHORT WAVE ENERGY WILL TARGET THE
NORTHWEST WITH A FAIR DEGREE OF UNCERTAINTY IN TIMING OF EVENTS AT
THIS POINT. SOLUTIONS ARE POINTING TO THE POTENTIAL FOR UP TO A
COUPLE BOUTS OF GUSTY SOUTH WINDS AT THE COAST MONDAY-TUESDAY.
STAVISH
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ029>031-624-625.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ021-022-615-618-619.
FLOOD WATCH UNTIL 1 PM PST THIS AFTERNOON FOR
ORZ021>024-615-616-618-619.
HIGH SURF ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ021-022-615-618-619.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ023-025-616-617-620-623.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR
ORZ027-028-617-621-623.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR ORZ026-622.
CA...HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
CAZ083>085-284-285.
FLASH FLOOD WATCH UNTIL 10 AM PST THIS MORNING FOR
CAZ080-081-280-281.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR CAZ081-281.
WIND ADVISORY FROM 1 PM TO 4 PM PST THIS AFTERNOON FOR
CAZ081-281.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 PM THIS EVENING
TO 4 AM PST SUNDAY FOR PZZ350-356-370-376.
STORM WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
PZZ350-356-370-376.
HAZARDOUS SEAS WARNING UNTIL 10 PM PST THIS EVENING FOR
PZZ350-356.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR PZZ310.
FLOOD WATCH UNTIL 1 PM PST THIS AFTERNOON FOR PZZ310.
HAZARDOUS SEAS WARNING UNTIL 10 PM PST THIS EVENING FOR
PZZ370-376.
$$
CC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
814 AM EST THU DEC 11 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL SPIN OVER THE NORTHEASTERN UNITED STATES
THROUGH SATURDAY. NORTHWEST FLOW OFF THE LAKES AND EVEN SOME
MOISTURE WRAPPING ALL THE WAY AROUND THE LOW WILL CREATE LIGHT
BUT NEARLY CONSTANT SNOW OVER THE NORTHERN MOUNTAINS AND
ALLEGHENIES INTO FRIDAY. RIDGING AND HIGH PRESSURE WILL SLOWLY
TRANSLATE EASTWARD TO REPLACE THE UPPER LOW OVER THE WEEKEND.
TEMPERATURES WILL MODERATE AND THE WEATHER REMAIN
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
COLD CONVEYOR BELT DEFORMATION SNOWFALL WITH SEVERAL EXTENSIVE
AND ENHANCED NW/SE BANDS CONTINUES TO IMPACT MUCH OF CENTRAL AND
EASTERN PA AT DAYBREAK. HIGH RES WRF ARW AND HRRR INDICATE THE
LIKELIHOOD OF THE BANDS PIVOTING A BIT MORE TO THE SOUTH THIS
MORNING...AND STAYING FOCUSED CLOSE TO THE RT 322 CORRIDOR...AND
POINTS TO THE EAST IN CENTRAL PENN. DUE TO MODEL AND UPPER AIR SOUNDINGS
THERE IS A POCKET OF WARM AIR ALOFT...ESPECIALLY IN AREAS OF WEAK
FORCING. DUE TO THIS AREAS OF FREEZING DRIZZLE REMAINS POSSIBLE AS
SOUTH AS BLAIR...HUNTINGDON AND CAMBRIA COUNTIES. BLACK ICE IS
POSSIBLE ON UNTREATED SURFACES WHICH COULD MAKE DRIVING
HAZARDOUS.
EXPANDED THE WINTER WEATHER ADVISORY FURTHER WEST AND SOUTH TO
INCLUDE THE LAURELS AND CENTRAL MOUNTAINS...ALSO ACROSS MUCH OF
THE LOWER SUSQ VALLEY /WHILE ALSO EXTENDING IT IN TIME THROUGH 18Z
TODAY/.
NUMEROUS REPORTS OF 2-4 INCHES OVERNIGHT ACROSS THE CENTRAL MTNS
AND SUSQ VALLEY. EXPECT AT LEAST ANOTHER INCH OR TWO OF SNOW TO
FALL INTO THE EARLY AFTERNOON WITH LOCALIZED ADDITIONAL 3 INCH
AMOUNTS. HEAVIER...AND MORE PERSISTENT SYNOPTIC/COLD CONVEYOR
SNOWS WILL DRIFT ACROSS THE NW MTNS AND STAY THERE INTO EARLY
THIS EVENING...WITH LAKE AND OROGRAPHIC ENHANCEMENT CAUSING 3 OR 4
INCHES TO FALL TODAY /IN ADDITION TO THE FEW INCHES OVERNIGHT.
TOTAL SNOW MAY BE TEETERING ON 24 HOUR WARNING CRITERIA OF 8
INCHES NEAR AND TO THE WEST OF KBFD BY THIS AFTERNOON.
TO COMPLICATE MATTERS...AREAS OF FREEZING DRIZZLE HAVE OCCURRED
DURING LULLS IN THE SNOWFALL /I.E. BETWEEN THE SLOWLY SWWD
DRIFTING SNOW BANDS/.
PREVIOUS DISCUSSION...
THE PRIMARY CONCERN FOR SIGNIFICANT SNOW WILL SHIFT TO THE NW
MTNS...AND PERHAPS SOME LOCATIONS AS FAR SE AS THE ALLEGHENY FRONT
IN CENTRAL PENN LATE THIS MORNING AND THIS AFTERNOON. MEAN SFC-850
MB FLOW WILL BACK ANOTHER 10-15 DEG TODAY /TO AROUND 310
DEG/...AND THE HEIGHT OF THE SUBSIDENCE INVERSION RISES TO AROUND
5 KFT AGL. THIS FAVORABLE THERMAL...AND SHEAR PROFILE WITH MDTLY
STRONG WINDS OF 30-40 KTS IN THE 2-5 KFT AGL LAYER WILL HELP TO
FORM AND DIRECT SOME WELL-DEFINED SNOW BANDS WELL INLAND.
ADDITIONAL SNOWFALL OF 4-6 INCHES CAN BE EXPECTED INVOF KFD OVER
THE NEXT 15 HRS.
HIGH TEMPS TODAY WILL ONLY RISE ABOUT 3-4F FROM THEIR EARLY
MORNING LOWS - AROUND 20F ACROSS THE NRN AND WRN MTNS...AND MID TO
UPPER 20S ELSEWHERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
THE PLUME OF DEEP MOISTURE/SNOWFALL GETS WEAKER AS THE UPPER LOW
STARTS TO SLIDE TO THE EAST TOWARD THE NEW ENG COAST.
THEREFORE...THERE SHOULD BE A DIMINISHING INTENSITY AND COVERAGE
TO THE SNOW...AND MAINLY JUST LAKE EFFECT LEFT FOR TONIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
THE LOW WILL CONTINUE TO MOVE SLOWLY NORTHWARD...WITH
PRECIPITATION POSSIBLE IN MINOR ACCUMULATIONS INTO FRIDAY MORNING.
HOWEVER ONCE THE NORTHWESTERLY FLOW CUTS OFF EARLY FRIDAY...THE
PRECIP WILL FADE WITH ONLY THE NW MTNS STILL RECEIVING LIGHT
SNOWFALL.
THE LATEST MID TO LONG RANGE MODELS ARE IN FAIR AGREEMENT INTO
FRIDAY NIGHT BUT THEN BEGIN TO DIVERGE ON THE TIMING AND MOVEMENT
OF THE LARGE UPPER LEVEL LOW. THE NAM AND GEFS ENSEMBLES HAS IT
STALLING OVER THE NORTHEAST...AND THEN DIVING SOUTHEASTWARD.
HOWEVER THE LATEST GFS AND EC GUIDANCE ARE IN DECENT AGREEMENT FOR
THE UPPER LOW TO NUDGE EASTWARD AND CONTINUE TO MOVE TO THE
NORTHEAST. THROUGH THIS TIMEFRAME A RIDGE WILL BUILD OVER THE
GREAT LAKES AND SLOWLY MOVE EASTWARD. THIS WILL BRING WARMER
TEMPERATURES AND MILD WEATHER FOR THE REGION THROUGH THE WEEKEND
AND INTO EARLY NEXT WEEK. A WARMER PATTERN WILL CONTINUE THROUGH
THE FIRST HALF OF NEXT WEEK WITH THE NEXT CHANCE FOR PRECIPITATION
BEING TUESDAY INT WEDNESDAY.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
A DEEP STORM SYSTEM OVER NEW ENGLAND THIS MORNING WILL
BE SLOW TO MOVE AWAY THE NEXT FEW DAYS.
THIS SYSTEM WILL KEEP GUSTY WINDS...BANDS OF SNOW...AND AT
TIMES MVFR TO LIFR CONDITIONS ACROSS THE AREA TODAY AND
TONIGHT.
CONDITIONS WILL SLOWLY IMPROVE FOR FRIDAY INTO THE WEEKEND...AS
HIGH PRESSURE BUILDS EASTWARD FROM THE PLAINS.
OUTLOOK...
FRI...MVFR/IFR IN -SHSN NORTH/WEST. MVFR TO VFR CENTRAL AND EAST.
SAT...MVFR CIGS/-SHSN EARLY WEST...BCMG VFR.
SUN-MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ006-010>012-017>019-024>028-037-041-042-045-046-049>053-
056>059-066.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ004-
005.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT/CERU
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/LAMBERT
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
704 AM EST THU DEC 11 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL SPIN OVER THE NORTHEASTERN UNITED STATES
THROUGH SATURDAY. NORTHWEST FLOW OFF THE LAKES AND EVEN SOME
MOISTURE WRAPPING ALL THE WAY AROUND THE LOW WILL CREATE LIGHT
BUT NEARLY CONSTANT SNOW OVER THE NORTHERN MOUNTAINS AND
ALLEGHENIES INTO FRIDAY. RIDGING AND HIGH PRESSURE WILL SLOWLY
TRANSLATE EASTWARD TO REPLACE THE UPPER LOW OVER THE WEEKEND.
TEMPERATURES WILL MODERATE AND THE WEATHER REMAIN
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
COLD CONVEYOR BELT DEFORMATION SNOWFALL WITH SEVERAL EXTENSIVE
AND ENHANCED NW/SE BANDS CONTINUES TO IMPACT MUCH OF CENTRAL AND
EASTERN PA AT DAYBREAK. HIGH RES WRF ARW AND HRRR INDICATE THE
LIKELIHOOD OF THE BANDS PIVOTING A BIT MORE TO THE SOUTH THIS
MORNING...AND STAYING FOCUSED CLOSE TO THE RT 322 CORRIDOR...AND
POINTS TO THE EAST IN CENTRAL PENN.
EXPANDED THE WINTER WEATHER ADVISORY FURTHER WEST AND ALSO ACROSS
MUCH OF THE LOWER SUSQ VALLEY /WHILE ALSO EXTENDING IT IN TIME
THROUGH 18Z TODAY/.
NUMEROUS REPORTS OF 2-4 INCHES OVERNIGHT ACROSS THE CENTRAL MTNS
AND SUSQ VALLEY. EXPECT AT LEAST ANOTHER INCH OR TWO OF SNOW TO
FALL INTO THE EARLY AFTERNOON WITH LOCALIZED ADDITIONAL 3 INCH
AMOUNTS. HEAVIER...AND MORE PERSISTENT SYNOPTIC/COLD CONVEYOR
SNOWS WILL DRIFT ACROSS THE NW MTNS AND STAY THERE INTO EARLY
THIS EVENING...WITH LAKE AND OROGRAPHIC ENHANCEMENT CAUSING 3 OR 4
INCHES TO FALL TODAY /IN ADDITION TO THE FEW INCHES OVERNIGHT.
TOTAL SNOW MAY BE TEETERING ON 24 HOUR WARNING CRITERIA OF 8
INCHES NEAR AND TO THE WEST OF KBFD BY THIS AFTERNOON.
TO COMPLICATE MATTERS...AREAS OF FREEZING DRIZZLE HAVE OCCURRED
DURING LULLS IN THE SNOWFALL /I.E. BETWEEN THE SLOWLY SWWD
DRIFTING SNOW BANDS/.
...PREVIOUS DISCUSSION...
THE PRIMARY CONCERN FOR SIGNIFICANT SNOW WILL SHIFT TO THE NW
MTNS...AND PERHAPS SOME LOCATIONS AS FAR SE AS THE ALLEGHENY FRONT
IN CENTRAL PENN LATE THIS MORNING AND THIS AFTERNOON. MEAN SFC-850
MB FLOW WILL BACK ANOTHER 10-15 DEG TODAY /TO AROUND 310
DEG/...AND THE HEIGHT OF THE SUBSIDENCE INVERSION RISES TO AROUND
5 KFT AGL. THIS FAVORABLE THERMAL...AND SHEAR PROFILE WITH MDTLY
STRONG WINDS OF 30-40 KTS IN THE 2-5 KFT AGL LAYER WILL HELP TO
FORM AND DIRECT SOME WELL-DEFINED SNOW BANDS WELL INLAND.
ADDITIONAL SNOWFALL OF 4-6 INCHES CAN BE EXPECTED INVOF KFD OVER
THE NEXT 15 HRS.
HIGH TEMPS TODAY WILL ONLY RISE ABOUT 3-4F FROM THEIR EARLY
MORNING LOWS - AROUND 20F ACROSS THE NRN AND WRN MTNS...AND MID TO
UPPER 20S ELSEWHERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
THE PLUME OF DEEP MOISTURE/SNOWFALL GETS WEAKER AS THE UPPER LOW
STARTS TO SLIDE TO THE EAST TOWARD THE NEW ENG COAST.
THEREFORE...THERE SHOULD BE A DIMINISHING INTENSITY AND COVERAGE
TO THE SNOW...AND MAINLY JUST LAKE EFFECT LEFT FOR TONIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
THE LOW WILL CONTINUE TO MOVE SLOWLY NORTHWARD...WITH
PRECIPITATION POSSIBLE IN MINOR ACCUMULATIONS INTO FRIDAY MORNING.
HOWEVER ONCE THE NORTHWESTERLY FLOW CUTS OFF EARLY FRIDAY...THE
PRECIP WILL FADE WITH ONLY THE NW MTNS STILL RECEIVING LIGHT
SNOWFALL.
THE LATEST MID TO LONG RANGE MODELS ARE IN FAIR AGREEMENT INTO
FRIDAY NIGHT BUT THEN BEGIN TO DIVERGE ON THE TIMING AND MOVEMENT
OF THE LARGE UPPER LEVEL LOW. THE NAM AND GEFS ENSEMBLES HAS IT
STALLING OVER THE NORTHEAST...AND THEN DIVING SOUTHEASTWARD.
HOWEVER THE LATEST GFS AND EC GUIDANCE ARE IN DECENT AGREEMENT FOR
THE UPPER LOW TO NUDGE EASTWARD AND CONTINUE TO MOVE TO THE
NORTHEAST. THROUGH THIS TIMEFRAME A RIDGE WILL BUILD OVER THE
GREAT LAKES AND SLOWLY MOVE EASTWARD. THIS WILL BRING WARMER
TEMPERATURES AND MILD WEATHER FOR THE REGION THROUGH THE WEEKEND
AND INTO EARLY NEXT WEEK. A WARMER PATTERN WILL CONTINUE THROUGH
THE FIRST HALF OF NEXT WEEK WITH THE NEXT CHANCE FOR PRECIPITATION
BEING TUESDAY INT WEDNESDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
A DEEP STORM SYSTEM OVER NEW ENGLAND THIS MORNING WILL
BE SLOW TO MOVE AWAY THE NEXT FEW DAYS.
THIS SYSTEM WILL KEEP GUSTY WINDS...BANDS OF SNOW...AND AT
TIMES MVFR TO LIFR CONDITIONS ACROSS THE AREA TODAY AND
TONIGHT.
CONDITIONS WILL SLOWLY IMPROVE FOR FRIDAY INTO THE WEEKEND...AS
HIGH PRESSURE BUILDS EASTWARD FROM THE PLAINS.
OUTLOOK...
FRI...MVFR/IFR IN -SHSN NORTH/WEST. MVFR TO VFR CENTRAL AND EAST.
SAT...MVFR CIGS/-SHSN EARLY WEST...BCMG VFR.
SUN-MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ006-010>012-017>019-027-028-037-041-042-045-046-049>053-
056>059-066.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ004-
005.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/LAMBERT
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS RENO NV
1239 PM PST THU DEC 11 2014
.UPDATE...
STRONG WINDS CONTINUE ACROSS WESTERN NEVADA AND THE EASTERN
SIERRA WITH NUMEROUS POWER OUTAGES...LARGE TREES DOWNED...AND
DAMAGE TO CAR PORTS AND FENCES. WE RECENTLY RECEIVED A REPORT OF A
106 MPH WIND GUST WITH DAMAGE TO HOMES INCLUDING WINDOWS BEING
BLOW OUT IN LUNDY CANYON NEAR THE JUNCTION OF CA-167 AND US-395 IN
MONO COUNTY.
RAIN AND SNOW CONTINUE TO MOVE INTO THE TAHOE BASIN THIS AFTERNOON
WITH SNOW LEVELS LOWERING TO 6500 TO 7000 FEET. HEAVY SNOW HAS
STARTED AT DONNER SUMMIT WITH AT LEAST A COUPLE INCHES OF
ACCUMULATIONS IN THE LAST HOUR. ACCUMULATIONS WILL BEGIN ON ECHO
SUMMIT AND CARSON PASS IN THE NEXT HOUR OR TWO. LIGHT SNOW IS ALSO
OCCURRING ALONG THE CREST IN MONO COUNTY AS FAR SOUTH AS MAMMOTH
MOUNTAIN. ONCE THE HEAVY SNOW STARTS, ACCUMULATIONS OF 2-4 INCHES
PER HOUR ARE LIKELY WITH HEAVY SNOW PERSISTING THROUGH TONIGHT
AROUND THE LAKE TAHOE BASIN, ALPINE COUNTY AND MONO COUNTY.
THE WINTER STORM WARNING FOR THE TAHOE BASIN BEGINS AT 1 PM. THE
WINTER STORM WARNING FOR MONO COUNTY BEGINS AT 7PM, BUT HEAVY SNOW
WILL PROBABLY START BEFORE THEN, SO MAY BUMP UP THE START TIME
CLOSER TO 4 PM. BRONG
&&
.SYNOPSIS...
A SIGNIFICANT WINTER STORM IS PRODUCING STRONG AND DAMAGING WINDS.
HEAVY RAIN AND SNOW WILL CONTINUE TO SPREAD SOUTH ALONG THE SIERRA
THE TODAY AND TONIGHT...WITH LIGHT RAIN SNOW ACROSS WESTERN NEVADA
TONIGHT. HIGH PRESSURE WILL BUILD OVER THE WEST THIS WEEKEND WITH
ADDITIONAL STORMS POSSIBLE NEXT WEEK.
&&
.PREVIOUS DISCUSSION... /ISSUED 913 AM PST THU DEC 11 2014/
UPDATE...
ONGOING HIGH WIND EVENT WITH REPORTS OF GUSTS TO 70 TO 90 MPH
ACROSS THE SIERRA AND WESTERN NEVADA. A PEAK GUST OF 93 MPH HAS
BEEN REPORTED BY A WEATHER SPOTTER IN DOUGLAS COUNTY. DOWNED TREES
HAVE BEEN REPORTED IN NORTH LAKE TAHOE, WITH DAMAGE REPORTS ACROSS
WESTERN NEVADA AS WELL. WINDS MAY START TO DIMINISH IN THE
NORTHERN SIERRA WITH PRECIPITATION MOVING INTO THE REGION LATE
THIS MORNING. WINDS ACROSS WESTERN NEVADA WILL REMAIN STRONG AND
GUSTY THROUGH THIS EVENING. BLOWING DUST HAS BEEN REPORTED AROUND
RENO- CARSON WITH AREAS OF VERY LOW VISIBILITY ALONG US-50 AND
I-80 IN LYON, PERSHING AND CHURCHILL COUNTIES.
PROFILERS, WEB CAMS AND SPOTTERS HAVE REPORTED SNOW LEVELS DOWN
TO 7000 FEET IN THE TAHOE BASIN AS LIGHT RAIN AND SNOW IS
IMPACTING I-80. SNOW LEVELS ARE DOWN NEAR 5500 FEET ACROSS LASSEN
AND PLUMAS COUNTIES WHERE HEAVY PRECIPITATION HAS BEEN OCCURRING
SINCE YESTERDAY EVENING. STORM TOTALS REMAIN ON TRACK ALONG THE
SIERRA CREST, WHERE 1-3 FEET OF SNOW WILL ACCUMULATE TODAY AND
TONIGHT. SNOW AMOUNTS MAY DROP OFF QUICKLY EAST OF THE CREST AS
THE MAIN PRECIPITATION BAND PIVOTS TO A NORTH-SOUTH ORIENTATION
AS THE MAIN LOW DIGS DOWN THE CALIFORNIA COAST TODAY. NO OTHER
CHANGES TO THE FORECAST FOR NOW. ADDITIONAL UPDATES WILL BE COMING
THROUGH THE DAY AS WIND WARNINGS ARE REPLACED BY WINTER STORM
WARNINGS IN THE SIERRA. BRONG
SYNOPSIS...
A SIGNIFICANT WINTER STORM IS PRODUCING STRONG AND DAMAGING
WINDS. HEAVY RAIN AND SNOW WILL CONTINUE TO SPREAD SOUTH ALONG
THE SIERRA THE TODAY AND TONIGHT...WITH LIGHT RAIN SNOW ACROSS
WESTERN NEVADA TONIGHT. HIGH PRESSURE WILL BUILD OVER THE WEST
THIS WEEKEND WITH ADDITIONAL STORMS POSSIBLE NEXT WEEK.
PREVIOUS DISCUSSION... /ISSUED 314 AM PST THU DEC 11 2014/
SHORT TERM...
WINDS HAVE BEGUN TO PICK UP IN THE TAHOE BASIN AND FAR WESTERN
NEVADA, WITH GUSTS TO 50 MPH AROUND TRUCKEE, AND 35-45 MPH
BETWEEN RENO AND CARSON CITY. RIDGE GUSTS ALONG THE SIERRA CREST
WEST OF TAHOE HAVE INCREASED TO NEAR 100 MPH. THIS IS JUST THE
START OF THE HIGH WIND EVENT WHICH HAS BEEN ADVERTISED FOR THE
PAST FEW DAYS, AND ALL WARNINGS AND ADVISORIES WILL REMAIN INTACT.
AREAS OF BLOWING DUST HAVE BEEN INCLUDED FOR MUCH OF WESTERN
NEVADA AND EASTERN MONO COUNTY FROM LATE MORNING THROUGH THIS
EVENING, AS MEANINGFUL PRECIPITATION IS NOT EXPECTED TO ARRIVE IN
THESE AREAS UNTIL LATER TONIGHT.
PRECIPITATION SO FAR HAS GENERALLY BEEN CONFINED TO NORTHEAST
CALIFORNIA WHERE RAINFALL BETWEEN 0.50 AND 1 INCH HAS BEEN
MEASURED IN CENTRAL PLUMAS COUNTY AND WESTERN LASSEN COUNTY. THESE
AREAS ARE EXPECTED TO RECEIVE THE LION`S SHARE OF THE RAIN AND
HIGH ELEVATION SNOW FOR MUCH OF TODAY AS MODEL GUIDANCE PULLS THE
MAIN MOISTURE FEED NORTH OF INTERSTATE 80 FOR MUCH OF TODAY.
RECENT RUNS OF THE HRRR MODEL ARE SIMILAR TO THE OPERATIONAL
MODELS, ALTHOUGH A SHORT PERIOD OF RAIN MAY BRUSH ACROSS THE
TRUCKEE-TAHOE VICINITY EARLY THIS MORNING. SNOW LEVELS FROM
PROFILER DATA WEST OF THE SIERRA CREST HAVE GENERALLY HOVERED
AROUND 8500 FEET, EXCEPT DIPPING BELOW 8000 FEET WITHIN HEAVIER
PRECIP BANDS. WE RAISED SNOW LEVELS ABOVE 8000 FEET FOR TAHOE AND
DELAYED DROPPING THE SNOW LEVEL BELOW 7000 FEET UNTIL MID-LATE
AFTERNOON.
FOR NORTHEAST CALIFORNIA, PRECIPITATION WILL GENERALLY FALL AS
RAIN EXCEPT FOR THE HIGHER MOUNTAINS OF WESTERN LASSEN COUNTY
THROUGH TODAY. TRAVEL IMPACTS ARE MORE LIKELY FOR HIGHER ELEVATION
ROADS HIGHWAY 44 WEST OF SUSANVILLE, FREDONYER SUMMIT AND YUBA
PASS BY LATE AFTERNOON OR EARLY EVENING.
FOR TONIGHT, THE MAIN IMPACTS TRANSITION FROM STRONG WINDS TO
HEAVY SIERRA SNOW AND VALLEY RAIN. A RAPID WORSENING OF TRAVEL
CONDITIONS IS EXPECTED EARLY THIS EVENING FOR THE MAIN PASSES
ALONG THE CREST INCLUDING I-80 AND HIGHWAY 50, THEN SPREADING
SOUTH ACROSS ALPINE AND MONO COUNTY LATER THIS EVENING. SNOW
AMOUNTS MAY NOT BE QUITE AS HIGH DUE TO A SHORTER DURATION OF
HEAVY SNOW. HOWEVER, SNOWFALL RATES COULD BE AS HIGH AS 3 INCHES
PER HOUR ABOVE 7000 FEET AND UP TO 2 INCHES PER HOUR IN THE TAHOE
BASIN AFTER THE COLD FRONT PASSES THROUGH DURING THE EVENING.
STEADY SNOW SHOULD CONTINUE THROUGH MID MORNING FRIDAY AROUND
TAHOE, AND INTO THE EARLY AFTERNOON FOR MONO COUNTY BEFORE
TAPERING TO SNOW SHOWERS. MORE INFORMATION ON SNOW AMOUNTS ARE
INCLUDED IN OUR WINTER STORM STATEMENTS.
FOR WESTERN NV, THE BEST CHANCES FOR RAIN WILL ARRIVE AFTER
MIDNIGHT AND CONTINUE THROUGH FRIDAY MORNING. THE GFS AND ECMWF
ARE PROJECTING AROUND 0.50 INCH AROUND RENO-SPARKS, WITH LOCALLY
HIGHER AMOUNTS UP TO 1 INCH POSSIBLE SOUTH OF CARSON CITY. IN
CONTRAST, THE NAM SHOWS MORE SHADOWING WITH PRECIP TOTALS OF 0.25
INCH OR LESS FOR RENO-CARSON-DOUGLAS. DUE TO THE DEEP MOISTURE
AND STRONG FORCING ALONG AND BEHIND THE FRONT, WE ARE FAVORING
THE HIGHER RAIN TOTALS AT THIS TIME. BY FRIDAY, SNOW LEVELS DROP
TO 5000-5500 FEET AS PRECIP WINDS DOWN WITH POSSIBLE LIGHT
ACCUMULATIONS ABOVE 5500 FEET, BUT LITTLE TO NO ACCUMULATION IS
EXPECTED FOR THE HEAVILY POPULATED AREAS OF WESTERN NEVADA.
SNOW SHOWERS WILL CONTINUE DIMINISHING FRIDAY NIGHT AND END BY
SATURDAY MORNING FROM WEST CENTRAL NV TO MONO COUNTY, WITH LITTLE
TO NO ADDITIONAL ACCUMULATIONS EXPECTED. DAYTIME TEMPS WILL BE
NOTABLY COOLER ON SATURDAY BUT NEAR MID DECEMBER NORMALS WITH
HIGHS MAINLY IN THE 40S FOR LOWER ELEVATIONS AND AROUND 40 FOR
SIERRA VALLEYS. MJD
LONG TERM...SUNDAY THROUGH WEDNESDAY...
LIMITED CHANGES WERE MADE TO THE EXTENDED FORECAST AS MODELS
REMAIN AT ODDS WITH EACH OVER ON THE DETAILS...BUT THE INDIVIDUAL
MODELS ARE CONSISTENT WITH THEMSELVES.
SHORT WAVE RIDGE OVERHEAD SUNDAY SHOULD BRING DRY WEATHER WITH LIGHT
WINDS. BUT A LACK OF MIXING WILL KEEP HIGH TEMPS IN THE VALLEYS FROM
CLIMBING ABOVE AVERAGE.
OPERATIONAL MODELS CONTINUE TO BRING THE NEXT SYSTEM INTO THE REGION
ANYWHERE FROM LATE SUNDAY EVENING...GEM...TO MONDAY AFTERNOON...
ECMWF. GFS IS BETWEEN THOSE TWO. THIS TROUGH IS COMING IN AS AN
ELONGATED SYSTEM WITH A HINT THAT A JET STREAK ROUNDING THE BASE OF
THE TROUGH WILL EITHER FORM A SECONDARY LOW SOUTH OF THE BAY AREA OR
PRODUCE A WEAKLY NEGATIVELY TILTED TROUGH. EITHER SOLUTION WOULD
TEND TO SLOW THE APPROACH OF THE MAIN TROUGH AND PCPN. FOR NOW HAVE
EDGED CLOSER TO ECMWF SOLUTION WITH THIS FEATURE.
OPERATIONAL MODELS ALSO SHOW A SECONDARY SHORT WAVE MOVING THROUGH
THE MAIN LONG WAVE TUESDAY. ECMWF KEEPS THE PATTERN STORMY THROUGH
WEDNESDAY IN WEAK WNW FLOW WHILE THE 00Z GFS SHOWED A BREAK IN THE
SERIES OF SHORT WAVES FOR WEDNESDAY. NOW THE 06Z GFS IS TRENDED MORE
TOWARD THE ECMWF.
BOTTOM LINE. WE SHOULD SEE AT LEAST LOW END POPS IN THE EXTENDED
EVERY DAY STARTING MONDAY. BECAUSE THESE SYSTEMS START
COOLER...SNOW LEVELS WILL BE LOW ENOUGH TO PRODUCE SOME SNOW AT
THE VALLEY FLOORS OF WESTERN NEVADA IF THESE SOLUTIONS HOLD. NONE
OF THESE SYSTEMS HAVE IMPRESSIVE AMOUNTS OF QPF...BUT AT LEAST THE
SIERRA SHOULD ADD A LITTLE TO THE HIGH ELEVATION SNOW PACK.
HIGH TEMPS EACH DAY SHOULD BE AT OR BELOW AVERAGE DUE TO PCPN AND
CLOUD COVER. 20
AVIATION...
SOUTHERLY GRADIENT WINDS STARTING TO INCREASE QUICKLY THROUGH THE
SIERRA...FAR NORTHEAST CALIFORNIA AND WESTERN NEVADA THIS MORNING.
GUSTS OVER THE SIERRA RIDGES HAVE ALREADY TOPPED 90 KTS WHILE SOME
SIERRA VALLEYS AND AREAS EAST OF THE SIERRA ARE SEEING GUSTS IN THE
45-50 KT RANGE. THIS SHOULD CONTINUE THROUGH THE MORNING HOURS AND
WILL LIKELY SPREAD A BIT FARTHER EAST...ALTHOUGH EAST OF HIGHWAY 95
THE STRONGEST GUSTS MAY NOT TOP 40-45 KT.
GUSTS UPWARDS OF 60-65 KTS ARE POSSIBLE THROUGH THIS EVENING BEFORE
THEY BEGIN TO DECREASE A BIT OVERNIGHT FOR FAR WESTERN NEVADA AND
THE SIERRA. UNIDIRECTIONAL FLOW FROM THE SFC UP TO ABOUT 5000 FT SHOULD
LIMIT DIRECTIONAL SHEAR...BUT THERE IS STILL LIKELY TO BE SOME SPEED
SHEAR THROUGH THE FIRST 4000-5000 FT. TURBULENCE SHOULD BE
WIDESPREAD TODAY AND WILL LIKELY BECOME QUITE ROUGH ON APPROACH AND
AT LOWER TO MID FLIGHT LEVELS OVER THE SIERRA AND TO THE EAST TODAY.
RAIN AND VERY HIGH ELEVATION SNOW HAS MOVED INTO NORTHERN AND FAR
NORTHEAST CALIFORNIA THIS MORNING. THE SHIELD OF PCPN SHOULD DRIFT
SOUTHEAST LATER TODAY AND TONIGHT...DRIVING CIGS TO IFR/MVFR
CONDITIONS AS IT MOVES. LATER THIS EVENING SNOW LEVELS BEGIN TO
DROP IN THE SIERRA FROM HIGHWAY 50 NORTH WITH ACCUMULATING SNOWS
ON SIERRA RUNWAYS. SNOW LEVELS FALL THROUGH MONO COUNTY OVERNIGHT.
BY FRIDAY MORNING WE COULD HAVE 4 TO 12 INCHES ON RUNWAYS IN THE
SIERRA...HIGHER AMOUNTS IF SNOW LEVELS FALL FASTER THROUGH THE
EVENING.
BOTTOM LINE...VERY STRONG WINDS AT THE SFC AND ALOFT TODAY WITH
WIDESPREAD TURBULENCE. DETERIORATING CIGS/VSBYS THROUGH THE
AFTERNOON AND EVENING. MOUNTAIN OBSCURATIONS DEVELOPING ALONG WITH
IFR CONDITIONS IN SNOW OVERNIGHT THROUGH THE SIERRA. LOWERED CIGS
AND RAIN IN WESTERN NEVADA VALLEYS. SNOW ACCUMULATIONS OF 4 TO 12
INCHES LIKELY FOR SIERRA RUNWAYS BY FRIDAY MORNING. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY NVZ003-005.
WINTER STORM WARNING UNTIL 1 PM PST FRIDAY NVZ002.
WIND ADVISORY UNTIL 4 AM PST FRIDAY NVZ001-004.
CA...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY CAZ070-071.
WINTER STORM WARNING UNTIL 10 AM PST FRIDAY ABOVE 5000 FEET FOR
CAZ071.
HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING CAZ073.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 4 PM PST FRIDAY
CAZ073.
WINTER STORM WARNING UNTIL 1 PM PST FRIDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
913 AM PST THU DEC 11 2014
.UPDATE...
ONGOING HIGH WIND EVENT WITH REPORTS OF GUSTS TO 70 TO 90 MPH
ACROSS THE SIERRA AND WESTERN NEVADA. A PEAK GUST OF 93 MPH HAS
BEEN REPORTED BY A WEATHER SPOTTER IN DOUGLAS COUNTY. DOWNED TREES
HAVE BEEN REPORTED IN NORTH LAKE TAHOE, WITH DAMAGE REPORTS ACROSS
WESTERN NEVADA AS WELL. WINDS MAY START TO DIMINISH IN THE
NORTHERN SIERRA WITH PRECIPITATION MOVING INTO THE REGION LATE
THIS MORNING. WINDS ACROSS WESTERN NEVADA WILL REMAIN STRONG AND
GUSTY THROUGH THIS EVENING. BLOWING DUST HAS BEEN REPORTED AROUND
RENO- CARSON WITH AREAS OF VERY LOW VISIBILITY ALONG US-50 AND
I-80 IN LYON, PERSHING AND CHURCHILL COUNTIES.
PROFILERS, WEB CAMS AND SPOTTERS HAVE REPORTED SNOW LEVELS DOWN
TO 7000 FEET IN THE TAHOE BASIN AS LIGHT RAIN AND SNOW IS
IMPACTING I-80. SNOW LEVELS ARE DOWN NEAR 5500 FEET ACROSS LASSEN
AND PLUMAS COUNTIES WHERE HEAVY PRECIPITATION HAS BEEN OCCURRING
SINCE YESTERDAY EVENING. STORM TOTALS REMAIN ON TRACK ALONG THE
SIERRA CREST, WHERE 1-3 FEET OF SNOW WILL ACCUMULATE TODAY AND
TONIGHT. SNOW AMOUNTS MAY DROP OFF QUICKLY EAST OF THE CREST AS
THE MAIN PRECIPITATION BAND PIVOTS TO A NORTH-SOUTH ORIENTATION
AS THE MAIN LOW DIGS DOWN THE CALIFORNIA COAST TODAY. NO OTHER
CHANGES TO THE FORECAST FOR NOW. ADDITIONAL UPDATES WILL BE COMING
THROUGH THE DAY AS WIND WARNINGS ARE REPLACED BY WINTER STORM
WARNINGS IN THE SIERRA. BRONG
&&
.SYNOPSIS...
A SIGNIFICANT WINTER STORM IS PRODUCING STRONG AND DAMAGING
WINDS. HEAVY RAIN AND SNOW WILL CONTINUE TO SPREAD SOUTH ALONG
THE SIERRA THE TODAY AND TONIGHT...WITH LIGHT RAIN SNOW ACROSS
WESTERN NEVADA TONIGHT. HIGH PRESSURE WILL BUILD OVER THE WEST
THIS WEEKEND WITH ADDITIONAL STORMS POSSIBLE NEXT WEEK.
&&
.PREVIOUS DISCUSSION... /ISSUED 314 AM PST THU DEC 11 2014/
SHORT TERM...
WINDS HAVE BEGUN TO PICK UP IN THE TAHOE BASIN AND FAR WESTERN
NEVADA, WITH GUSTS TO 50 MPH AROUND TRUCKEE, AND 35-45 MPH
BETWEEN RENO AND CARSON CITY. RIDGE GUSTS ALONG THE SIERRA CREST
WEST OF TAHOE HAVE INCREASED TO NEAR 100 MPH. THIS IS JUST THE
START OF THE HIGH WIND EVENT WHICH HAS BEEN ADVERTISED FOR THE
PAST FEW DAYS, AND ALL WARNINGS AND ADVISORIES WILL REMAIN INTACT.
AREAS OF BLOWING DUST HAVE BEEN INCLUDED FOR MUCH OF WESTERN
NEVADA AND EASTERN MONO COUNTY FROM LATE MORNING THROUGH THIS
EVENING, AS MEANINGFUL PRECIPITATION IS NOT EXPECTED TO ARRIVE IN
THESE AREAS UNTIL LATER TONIGHT.
PRECIPITATION SO FAR HAS GENERALLY BEEN CONFINED TO NORTHEAST
CALIFORNIA WHERE RAINFALL BETWEEN 0.50 AND 1 INCH HAS BEEN
MEASURED IN CENTRAL PLUMAS COUNTY AND WESTERN LASSEN COUNTY. THESE
AREAS ARE EXPECTED TO RECEIVE THE LION`S SHARE OF THE RAIN AND
HIGH ELEVATION SNOW FOR MUCH OF TODAY AS MODEL GUIDANCE PULLS THE
MAIN MOISTURE FEED NORTH OF INTERSTATE 80 FOR MUCH OF TODAY.
RECENT RUNS OF THE HRRR MODEL ARE SIMILAR TO THE OPERATIONAL
MODELS, ALTHOUGH A SHORT PERIOD OF RAIN MAY BRUSH ACROSS THE
TRUCKEE-TAHOE VICINITY EARLY THIS MORNING. SNOW LEVELS FROM
PROFILER DATA WEST OF THE SIERRA CREST HAVE GENERALLY HOVERED
AROUND 8500 FEET, EXCEPT DIPPING BELOW 8000 FEET WITHIN HEAVIER
PRECIP BANDS. WE RAISED SNOW LEVELS ABOVE 8000 FEET FOR TAHOE AND
DELAYED DROPPING THE SNOW LEVEL BELOW 7000 FEET UNTIL MID-LATE
AFTERNOON.
FOR NORTHEAST CALIFORNIA, PRECIPITATION WILL GENERALLY FALL AS
RAIN EXCEPT FOR THE HIGHER MOUNTAINS OF WESTERN LASSEN COUNTY
THROUGH TODAY. TRAVEL IMPACTS ARE MORE LIKELY FOR HIGHER ELEVATION
ROADS HIGHWAY 44 WEST OF SUSANVILLE, FREDONYER SUMMIT AND YUBA
PASS BY LATE AFTERNOON OR EARLY EVENING.
FOR TONIGHT, THE MAIN IMPACTS TRANSITION FROM STRONG WINDS TO
HEAVY SIERRA SNOW AND VALLEY RAIN. A RAPID WORSENING OF TRAVEL
CONDITIONS IS EXPECTED EARLY THIS EVENING FOR THE MAIN PASSES
ALONG THE CREST INCLUDING I-80 AND HIGHWAY 50, THEN SPREADING
SOUTH ACROSS ALPINE AND MONO COUNTY LATER THIS EVENING. SNOW
AMOUNTS MAY NOT BE QUITE AS HIGH DUE TO A SHORTER DURATION OF
HEAVY SNOW. HOWEVER, SNOWFALL RATES COULD BE AS HIGH AS 3 INCHES
PER HOUR ABOVE 7000 FEET AND UP TO 2 INCHES PER HOUR IN THE TAHOE
BASIN AFTER THE COLD FRONT PASSES THROUGH DURING THE EVENING.
STEADY SNOW SHOULD CONTINUE THROUGH MID MORNING FRIDAY AROUND
TAHOE, AND INTO THE EARLY AFTERNOON FOR MONO COUNTY BEFORE
TAPERING TO SNOW SHOWERS. MORE INFORMATION ON SNOW AMOUNTS ARE
INCLUDED IN OUR WINTER STORM STATEMENTS.
FOR WESTERN NV, THE BEST CHANCES FOR RAIN WILL ARRIVE AFTER
MIDNIGHT AND CONTINUE THROUGH FRIDAY MORNING. THE GFS AND ECMWF
ARE PROJECTING AROUND 0.50 INCH AROUND RENO-SPARKS, WITH LOCALLY
HIGHER AMOUNTS UP TO 1 INCH POSSIBLE SOUTH OF CARSON CITY. IN
CONTRAST, THE NAM SHOWS MORE SHADOWING WITH PRECIP TOTALS OF 0.25
INCH OR LESS FOR RENO-CARSON-DOUGLAS. DUE TO THE DEEP MOISTURE
AND STRONG FORCING ALONG AND BEHIND THE FRONT, WE ARE FAVORING
THE HIGHER RAIN TOTALS AT THIS TIME. BY FRIDAY, SNOW LEVELS DROP
TO 5000-5500 FEET AS PRECIP WINDS DOWN WITH POSSIBLE LIGHT
ACCUMULATIONS ABOVE 5500 FEET, BUT LITTLE TO NO ACCUMULATION IS
EXPECTED FOR THE HEAVILY POPULATED AREAS OF WESTERN NEVADA.
SNOW SHOWERS WILL CONTINUE DIMINISHING FRIDAY NIGHT AND END BY
SATURDAY MORNING FROM WEST CENTRAL NV TO MONO COUNTY, WITH LITTLE
TO NO ADDITIONAL ACCUMULATIONS EXPECTED. DAYTIME TEMPS WILL BE
NOTABLY COOLER ON SATURDAY BUT NEAR MID DECEMBER NORMALS WITH
HIGHS MAINLY IN THE 40S FOR LOWER ELEVATIONS AND AROUND 40 FOR
SIERRA VALLEYS. MJD
LONG TERM...SUNDAY THROUGH WEDNESDAY...
LIMITED CHANGES WERE MADE TO THE EXTENDED FORECAST AS MODELS
REMAIN AT ODDS WITH EACH OVER ON THE DETAILS...BUT THE INDIVIDUAL
MODELS ARE CONSISTENT WITH THEMSELVES.
SHORT WAVE RIDGE OVERHEAD SUNDAY SHOULD BRING DRY WEATHER WITH LIGHT
WINDS. BUT A LACK OF MIXING WILL KEEP HIGH TEMPS IN THE VALLEYS FROM
CLIMBING ABOVE AVERAGE.
OPERATIONAL MODELS CONTINUE TO BRING THE NEXT SYSTEM INTO THE REGION
ANYWHERE FROM LATE SUNDAY EVENING...GEM...TO MONDAY AFTERNOON...
ECMWF. GFS IS BETWEEN THOSE TWO. THIS TROUGH IS COMING IN AS AN
ELONGATED SYSTEM WITH A HINT THAT A JET STREAK ROUNDING THE BASE OF
THE TROUGH WILL EITHER FORM A SECONDARY LOW SOUTH OF THE BAY AREA OR
PRODUCE A WEAKLY NEGATIVELY TILTED TROUGH. EITHER SOLUTION WOULD
TEND TO SLOW THE APPROACH OF THE MAIN TROUGH AND PCPN. FOR NOW HAVE
EDGED CLOSER TO ECMWF SOLUTION WITH THIS FEATURE.
OPERATIONAL MODELS ALSO SHOW A SECONDARY SHORT WAVE MOVING THROUGH
THE MAIN LONG WAVE TUESDAY. ECMWF KEEPS THE PATTERN STORMY THROUGH
WEDNESDAY IN WEAK WNW FLOW WHILE THE 00Z GFS SHOWED A BREAK IN THE
SERIES OF SHORT WAVES FOR WEDNESDAY. NOW THE 06Z GFS IS TRENDED MORE
TOWARD THE ECMWF.
BOTTOM LINE. WE SHOULD SEE AT LEAST LOW END POPS IN THE EXTENDED
EVERY DAY STARTING MONDAY. BECAUSE THESE SYSTEMS START
COOLER...SNOW LEVELS WILL BE LOW ENOUGH TO PRODUCE SOME SNOW AT
THE VALLEY FLOORS OF WESTERN NEVADA IF THESE SOLUTIONS HOLD. NONE
OF THESE SYSTEMS HAVE IMPRESSIVE AMOUNTS OF QPF...BUT AT LEAST THE
SIERRA SHOULD ADD A LITTLE TO THE HIGH ELEVATION SNOW PACK.
HIGH TEMPS EACH DAY SHOULD BE AT OR BELOW AVERAGE DUE TO PCPN AND
CLOUD COVER. 20
AVIATION...
SOUTHERLY GRADIENT WINDS STARTING TO INCREASE QUICKLY THROUGH THE
SIERRA...FAR NORTHEAST CALIFORNIA AND WESTERN NEVADA THIS MORNING.
GUSTS OVER THE SIERRA RIDGES HAVE ALREADY TOPPED 90 KTS WHILE SOME
SIERRA VALLEYS AND AREAS EAST OF THE SIERRA ARE SEEING GUSTS IN THE
45-50 KT RANGE. THIS SHOULD CONTINUE THROUGH THE MORNING HOURS AND
WILL LIKELY SPREAD A BIT FARTHER EAST...ALTHOUGH EAST OF HIGHWAY 95
THE STRONGEST GUSTS MAY NOT TOP 40-45 KT.
GUSTS UPWARDS OF 60-65 KTS ARE POSSIBLE THROUGH THIS EVENING BEFORE
THEY BEGIN TO DECREASE A BIT OVERNIGHT FOR FAR WESTERN NEVADA AND
THE SIERRA. UNIDIRECTIONAL FLOW FROM THE SFC UP TO ABOUT 5000 FT SHOULD
LIMIT DIRECTIONAL SHEAR...BUT THERE IS STILL LIKELY TO BE SOME SPEED
SHEAR THROUGH THE FIRST 4000-5000 FT. TURBULENCE SHOULD BE
WIDESPREAD TODAY AND WILL LIKELY BECOME QUITE ROUGH ON APPROACH AND
AT LOWER TO MID FLIGHT LEVELS OVER THE SIERRA AND TO THE EAST TODAY.
RAIN AND VERY HIGH ELEVATION SNOW HAS MOVED INTO NORTHERN AND FAR
NORTHEAST CALIFORNIA THIS MORNING. THE SHIELD OF PCPN SHOULD DRIFT
SOUTHEAST LATER TODAY AND TONIGHT...DRIVING CIGS TO IFR/MVFR
CONDITIONS AS IT MOVES. LATER THIS EVENING SNOW LEVELS BEGIN TO
DROP IN THE SIERRA FROM HIGHWAY 50 NORTH WITH ACCUMULATING SNOWS
ON SIERRA RUNWAYS. SNOW LEVELS FALL THROUGH MONO COUNTY OVERNIGHT.
BY FRIDAY MORNING WE COULD HAVE 4 TO 12 INCHES ON RUNWAYS IN THE
SIERRA...HIGHER AMOUNTS IF SNOW LEVELS FALL FASTER THROUGH THE
EVENING.
BOTTOM LINE...VERY STRONG WINDS AT THE SFC AND ALOFT TODAY WITH
WIDESPREAD TURBULENCE. DETERIORATING CIGS/VSBYS THROUGH THE
AFTERNOON AND EVENING. MOUNTAIN OBSCURATIONS DEVELOPING ALONG WITH
IFR CONDITIONS IN SNOW OVERNIGHT THROUGH THE SIERRA. LOWERED CIGS
AND RAIN IN WESTERN NEVADA VALLEYS. SNOW ACCUMULATIONS OF 4 TO 12
INCHES LIKELY FOR SIERRA RUNWAYS BY FRIDAY MORNING. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY NVZ003-005.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON NVZ002.
WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO 1 PM PST FRIDAY
NVZ002.
WIND ADVISORY UNTIL 4 AM PST FRIDAY NVZ001-004.
CA...HIGH WIND WARNING UNTIL 4 AM PST FRIDAY CAZ070-071.
WINTER STORM WARNING UNTIL 10 AM PST FRIDAY ABOVE 5000 FEET FOR
CAZ071.
HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING CAZ073.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 4 PM PST FRIDAY
CAZ073.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON CAZ072.
WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO 1 PM PST FRIDAY
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
825 AM PST Thu Dec 11 2014
.Synopsis...
A Strong Pacific storm impacts the area into Friday bringing
heavy precipitation including significant mountain snow and strong
winds. A mainly dry weekend is expected with the next chance of
precipitation early next week.
&&
.Discussion...
Strong Pacific storm impacting NorCal this morning. Satellite
imagery showing deepening low center, near 977 mb, about 130 nm
off the southern Oregon coast with associated frontal system
extending through WA/OR/CA. Baroclinic zone tapping into
atmospheric river extending from CA southwestward into Hawaii.
Blended TPW showing PWs peaking near 1.8 inches along the NorCal
coast. Very tight pressure gradient extends from low center
through Central Cal. Warm sector precip has occurred overnight
with strong SE winds. As a result, strong isentropic lift and
favorable orographics into the Shasta basin have lead to
impressive rainfall amounts with some rain gauges reporting over
4.5 inches of rain with about 2.5 inches at Redding ASOS. KRDD
also reported a wind gust at 63 mph this morning as the cold front
moved into the area. Farther south, near the Bay Area, several
NCFR (narrow cold frontal bands) seen on radar along leading edge
of cold front indicating strong low level southerly jet. Both the
KBBX and KDAX VAD profilers showing 65 kt SE winds at 2K ft above
the surface. Strongest winds expected along the front this morning
as it moves inland with downed trees and power outages continuing.
Heavy precip over the northern CWA attm will spread south and
east today as the atmospheric river sags south over the CWA. Urban
flood warning issued for northern/northwestern portions of the CWA
already and additional ones likely for the southern half latter
this morning. Instability progs indicating thunderstorm chances
today look unlikely.
Very strong winds occurring in the mountains this morning with
KBLU reporting a gust to 69 mph. Snow levels however remain high
attm, above 8000 feet, but will gradually lower from north to
south today into tonight as colder air is ushered into the area.
3KM HRRR showing heaviest precip in the Lassen Park/Western Plumas
area through 00z Friday and over the Northern Sierra Nevada this
afternoon into tonight. Snow levels will lower to around 4000 to
5000 feet by Friday morning with several feet of snow expected
over the higher terrain.
Front drops south of the CWA tonight then associated upper trough
moves through Friday keeping unstable conditions over Interior
NorCal. Showers and isolated thunderstorms expected with best
instability depicted over the Coastal range, Delta and Southern Sac
Valley into the San Joaquin Valley. Trough axis moves through
Friday night then upper ridging progged over the weekend with
drier weather and valley fog.
PCH
&&
.Extended Discussion (Monday through Thursday)
Ridge shifts off to the east Monday ahead of an offshore upper level
trough that will swing into the area Monday into midweek. As
several waves drop SE in the flow, chances for precipitation will
return. Model differences remain in timing and strength of trough
and associated shortwaves so have continued with chance of precip
through midweek. The system will be weaker than this week`s with
less precip but colder with lower snow levels. Valley daytime
temps will be in the 50s with 30s to 40s in the foothills and
mountains. CEO
&&
.Aviation...
Strong Pacific front offshore will be moving inland today. Wet
and very windy conditions will spread over the TAF sites today.
Already MVFR cigs/vsbys in RDD/RBL will spread over Sac area and
SCK TAF sites during afternoon and evening. Main band of moderate
to heavy rain will cause IFR conditions. Southerly winds
increasing over TAF sites peaking between 15z-20z with gusts up
to 55 kts possible in the Valley. Airport Weather Warnings have
been issued for Redding and Stockton Airports for the winds. IFR
and areas of LIFR conditions developing over the Siernev obscuring
terrain. Snow levels 7000-8000 ft lowering to around 5000 ft
Thursday evening.
&&
.STO Watches/Warnings/Advisories...
high wind warning until 2 pm pst this afternoon west slope
northern sierra nevada...western plumas county/lassen park.
flood watch through friday evening burney basin / eastern shasta
county...central sacramento valley...clear lake/southern lake
county...mountains southwestern shasta county to northern lake
county...northeast foothills/sacramento valley...northern
sacramento valley...shasta lake area / northern shasta county...
western plumas county/lassen park.
flood watch through friday evening carquinez strait and delta...
motherlode...northern san joaquin valley...southern sacramento
valley...west slope northern sierra nevada.
blizzard warning until 4 am pst friday above 6500 feet in the
west slope northern sierra nevada.
high wind warning until 2 pm pst this afternoon burney basin /
eastern shasta county...carquinez strait and delta...central
sacramento valley...clear lake/southern lake county...
motherlode...mountains southwestern shasta county to northern
lake county...northeast foothills/sacramento valley...northern
sacramento valley...northern san joaquin valley...shasta lake
area / northern shasta county...southern sacramento valley.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1128 AM CST THU DEC 11 2014
.SHORT TERM...
338 AM CST
THROUGH FRIDAY...
AS AN INDICATION OF THE QUIET PERIOD OF WEATHER WE CURRENTLY ARE
EXPERIENCING...THE MAIN FOCUS OF THIS FORECAST PACKAGE AND THE
WEATHER ELEMENT THAT GENERATED THE MOST DISCUSSION BETWEEN
NEIGHBORING OFFICES IS SKY COVER. SO NOT A LOT GOING ON IN THE NEAR
TERM...BUT SKY COVER IS A BIT CHALLENGING AND OF COURSE HAS
RAMIFICATIONS FOR DAYTIME HIGHS AND OVERNIGHT LOWS.
MODELS HAVE NOT REALLY BEEN HANDLING THE SKY TRENDS ALL THAT
WELL...THOUGH LOW LEVELS OF THE NAM AROUND 975 TO 925MB ARE PROBABLY
COMING THE CLOSEST IN DEPICTING THE ONGOING CLOUDINESS. LIKELY
CONTRIBUTING TO MODEL CONFUSION IS THE FACT THAT THE EMBEDDED
CLOUDINESS IS TRAPPED BELOW A STEEP INVERSION UNDER THE AXIS OF THE
STRONG SFC RIDGE SITTING TO OUR WEST...WHILE CLOUDS ARE BEING
SCOURED OUT UNDER THE BETTER MIXED CIRCULATION AROUND THE BACK SIDE
OF THE LOW SITTING OVER NEW ENGLAND. EVEN IF SOME OF THIS MOISTURE
UNDER THE INVERSION DOES BEGIN TO MIX OUT...THERE STILL IS ENOUGH
CYCLONIC FLOW ALOFT AND POCKETS OF SHORTWAVE ENERGY TO SUPPORT THE
IDEA OF CONTINUED CLOUDINESS INTO THE WEEKEND. IF NOTHING
ELSE...PERSISTENCE HAS SO FAR PROVEN EFFECTIVE IN THIS REGIME...SO
DAYTIME HIGHS WILL BE NUDGED SLIGHTLY DOWNWARD AND OVERNIGHT LOWS
SLIGHTLY UPWARD UNTIL BETTER SIGNALS OF CLEARING WOULD INDICATE
OTHERWISE.
LENNING
&&
.LONG TERM...
338 AM CST
FRIDAY NIGHT THROUGH THURSDAY...
FRIDAY NIGHT AND SATURDAY WILL REMAIN DRY AND WE MAY FINALLY SEE A
BIT OF CLEARING AS THE RIDGE AXIS SLOWLY MOVES OVERHEAD...BUT AM
NOT WILLING TO DEVIATE MUCH FROM PERSISTENCE UNTIL THIS ACTUALLY
STARTS HAPPENING. BY SATURDAY NIGHT INTO SUNDAY...AND MORE SO ON
MONDAY INTO TUESDAY...MOISTURE STARTS MAKING A RETURN TO THE AREA
ON THE BACK SIDE OF THE RIDGE THAT HAS FINALLY SLID TO OUR
EAST....THOUGH POPS REMAIN LOW IN THE SLIGHT CHANCE RANGE THROUGH
SUNDAY.
ON MONDAY THE ECMWF AND GFS BOTH SUGGEST THE PRESENCE OF AN
APPROACHING LOW TRACKING ALONG THE 37TH PARALLEL...AND A TROUGH OR
FRONTAL ZONE EXTENDING NORTH OF THIS FEATURE INTO CANADA. ALTHOUGH
THE LOW CENTER MAY PASS TO OUR SOUTH...THERE IS ENOUGH MILD AIR
WRAPPED UP WITH THIS SYSTEM THAT RAIN IS AGAIN THE MOST LIKELY FORM
OF PRECIPITATION AT LEAST UNTIL THE TRAILING RIDGE PUSHES COLDER AIR
INTO THE AREA ON TUESDAY AND WEDNESDAY...AT WHICH POINT MESOSCALE
LAKE EFFECTS WOULD BE THE PRIMARY DRIVER OF LIFT AND SATURATION.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* PERIODS OF MVFR CIGS.
BMD
//DISCUSSION...UPDATED 18Z...
RIDGE OF HIGH PRESSURE IS CENTERED ALONG THE MID AND UPPER
MISSISSIPPI VALLEY THIS AFTERNOON WITH BROAD AREA OF IFR/MVFR
STRATUS IN PLACE ACROSS MUCH OF THE REGION. THE EASTERN EDGE HAS
BEEN ERODING THOUGH...WITH THE CLEARING LINE ADVANCING AT LEAST
TEMPORARILY OVER THE CHICAGO TERMINALS. IT IS EXPECTED THAT THIS
CLEARING WILL SLOW BY LATE AFTERNOON...THE MVFR CIGS SHOULD BEGIN TO
SPREAD BACK EAST OVER THE TERMINALS THROUGH THE REMAINDER OF THE
NIGHT. ONCE AGAIN EXPECT LOWER END MVFR AND POSSIBLY SOME IFR IN THE
AREA. WINDS SHOULD BE FAIRLY LIGHT AND GENERALLY OUT OF THE WEST
THROUGH THE PERIOD.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN MVFR OVERSPREADING TERMINALS AGAIN
LATE THIS AFTERNOON OR THIS EVENING AND PERSISTING OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. WX NIL.
SATURDAY...VFR. WX NIL.
SUNDAY...SLIGHT CHANCE RAIN.
MONDAY...CHANCE RAIN. CHANCE MVFR CIGS.
TUESDAY...CHANCE RAIN MIXING WITH SNOW LATE.
WEDNESDAY...VFR. WX NIL.
KREIN
&&
.MARINE...
315 AM CST
PERSISTENT NWLY FLOW WILL CONTINUE OVER THE NEXT FEW DAYS AS HIGH
PRESSURE BUILDS ACROSS THE MISSISSIPPI VALLEY AND WESTERN GREAT
LAKE S REGION AND DEEP LOW PRESSURE SLOWLY MOVES THROUGH NEW
ENGLAND. THE HIGH PRESSURE WILL GRADUALLY SLIDE SOUTH INTO THE
LOWER OHIO VALLEY AND LOWER MISSISSIPPI VALLEY AS A TROUGH OF LOW
PRESSURE DEVELOPS OVER THE NORTHERN PLAINS AND THE NEW ENGLAND LOW
BEGINS TO LIFT OUT TO THE NORTHEAST. WINDS OVER THE LAKE WILL
GRADUALLY BACK THROUGH WESTERLY TO SOUTHWESTERLY BY SATURDAY
NIGHT. A MODERATE GRADIENT WILL REMAIN IN PLACE OVER THE LAKE
THROUGH THE PERIOD WITH WINDS GENERALLY IN THE 15-25 KT RANGE WITH
OCNL PERIODS OF 30KT WINDS.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1031 AM CST Thu Dec 11 2014
.UPDATE...
ISSUED AT 1025 AM CST THU DEC 11 2014
No major updates were made to the current forecast as it appears
to be on track. However...will continue to monitor the cloud
cover as some clearing has already begun near Terre Haute IN and
in the Chicago metro area. Skies will remain cloudy for right now
with further updates later if clearing trend appears to extend
into the CWA. May need to adjust temperatures a little later if
clearing develops...but feel those look to be on track for the
time being as well.
&&
.SHORT TERM...(Today)
ISSUED AT 336 AM CST THU DEC 11 2014
Little relief from the cloud cover is expected today. Some clearing
has developed over lower Michigan and northern Indiana, but NW
surface winds will not be conducive to pulling that dry air into
Illinois. An expansive area of clouds remains entrenched across the
Midwest back to the eastern Dakotas and south to Texas. Besides an
isolated break in the clouds this afternoon in eastern areas, it
looks likely that the strong low level temperature inversion will
provide cloudy skies for at least another day.
Diurnal temperature swings yesterday were only 4 degrees in most
areas, and similar conditions are expected today with little to no
airmass change and little to no sunshine. Will keep highs in the mid
to upper 30s with light northwest winds under stalled high pressure.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 336 AM CST THU DEC 11 2014
Clouds that will not go away...that is the first and major issue
with this forecast. Considering the strength of the inversion in the
forecast soundings...the satellite imagery, and the persistence
forecast, have completely ignored the modeled sky cover. Keeping
the majority of the forecast in the shorter term covered in stratus.
As a result, adjusting the temperatures a bit to cooler in the day
time and warmer in the overnights. Southerly winds kicking in on
Friday though will help with WAA without too much in the way of
sunshine. Temps over the weekend well above normal, though cloudy.
Best chances to see broken clouds may be on Saturday before clouding
up again in advance of the next system.
Precip chances return late in the weekend...Sunday night...and into
the first of the work week, though the confidence in the upper air
pattern is low. Have been too many iterations about handling the
500mb low/trof. That being said, the surface forecast remains rain,
just a question of when. The timing of the low and the track are
starting to diverge yet again, though the models are wet Monday and
Monday night...now lingering into Tuesday. Best chances are Monday
and Monday night, with some warm advection showers possible late
Sunday night.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 540 AM CST THU DEC 11 2014
The NAM/GFS/HRRR all continue to advertise some clearing across
central IL today. The HRRR shows clearing developing near CMI
around 19z and expanding toward PIA and SPI the rest of the
afternoon. The subsidence inversion remains as strong as it has
been the last few days, and the depth of the cloud layer remains
at 1.5-2k feet. While a few breaks may develop today, especially
toward CMI, we will continue the cloudy MVFR forecast until
satellite and obs confirm changes in that pattern. Winds will
be light northwest this morning, with a shift toward more westerly
by afternoon, as a surface ridge axis shifts just east of the
area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ALW
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS DES MOINES IA
338 PM CST THU DEC 11 2014
.SHORT TERM /TONIGHT/...
ISSUED AT 337 PM CST THU DEC 11 2014
CLOUDS AND TEMPERATURES WILL CONTINUE TO BE THE FORECAST PROBLEM
TONIGHT AND LIKELY FOR THE FORESEEABLE FUTURE. SOUNDINGS SHOW AN
UNBREAKABLE INVERSION THAT ACTUALLY STRENGTHENS TONIGHT. I SEE NO
REASON WHY LOW CLOUDS AND FOG SHOULD NOT CONTINUE THROUGH THE
OVERNIGHT AND BEYOND. LAST NIGHT THERE WERE ISOLATED AREAS OF
DENSE FOG WHERE VISIBILITIES DROPPED TO A QUARTER MILE OR SO AS
WELL AS SOME PATCHY FREEZING DRIZZLE THAT OCCURRED FOR A COUPLE
HOURS THIS MORNING. THIS SCENARIO WILL LIKELY REPEAT TONIGHT. THE
QUESTION BECOMES WILL IT BE WIDESPREAD ENOUGH FOR AN ADVISORY.
I DO EXPECT SOME EXPANSION OF LOCATIONS THAT EXPERIENCE DENSE FOG
HOWEVER IT MAY NOT BE WIDESPREAD ENOUGH FOR AN ADVISORY AND THUS DID
NOT PUT ONE OUT. I WILL HOWEVER ADVISE THE EVENING SHIFT THAT ONE
ACROSS THE NORTHWEST OR FAR NORTH MAY BE NECESSARY LATE TONIGHT.
TAKING A LOOK AT THE 925MB MOISTURE ADVECTION YOU CAN SEE THAT THE
BETTER ADVECTION OCCURS BETWEEN 09Z AND 12Z INTO FRIDAY MORNING.
THE NAM IS THE MORE AGGRESSIVE WITH THIS BUT THE RAP ALSO INCREASES
THE MOISTURE ADVECTION DURING THIS TIME...JUST FURTHER NW. TAKING A
LOOK AT THE HRRR AVIATION FLIGHT RULE PARAMETER AND VISIBILITY AND
THE HOPWRF VISIBILITY THEY CONFIRM THAT LOWER VISIBILITIES OCCUR
ACROSS THE NW MAINLY AFTER 09Z. IF DENSE FOG WERE TO OCCUR IT WOULD
MOST LIKELY BE NEAR THE END OF THE PERIOD INTO FRIDAY MORNING.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 337 PM CST THU DEC 11 2014
AREAS OF FOG ARE EXPECTED FRIDAY MORNING. PATCHES OF FREEZING
DRIZZLE/MIST THIS MORNING WILL BE A CONCERN AGAIN FRIDAY MORNING
OVER NORTHERN IOWA. LOW LEVEL MOISTURE DEPTHS WILL BE SUPPRESSED A
BIT FROM AROUND 2.5 KFT TODAY TO AROUND 2 KFT FRIDAY MORNING. THAT
SAID...LOW LEVEL COLLISION COALESCENCE SHOULD STILL BE ONGOING
ENOUGH FROM MOISTURE ADVECTION FOR A FEW PATCHES OF MIST OR
DRIZZLE TO OCCUR AND COULD CAUSE A FEW ICY SPOTS ON ROADWAYS.
OTHERWISE...THE WARMING PROCESS WILL REMAIN SLOW ON FRIDAY AS THE
UPPER INVERSION KEEPS MOISTURE BELOW TRAPPED AND WILL KEEP
WIDESPREAD STRATUS DECK IN PLACE. HIGH TEMPERATURE POTENTIAL WILL
BE DIRECTLY CORRELATED TO LOW LEVEL MOISTURE ADVECTION PROCESSES.
HIGH TEMPERATURES WILL NOT STRAY FAR FROM DEWPOINT VALUES AND HAVE
CONTINUE TO TEMPER HIGHS. TEMPERATURES WILL BE STEADY TO RISING
FRIDAY NIGHT. THE LOW LEVEL MOISTURE PLUME WILL CONTINUE TO ADVECT
IN AND DEEPEN SATURDAY INTO SATURDAY NIGHT. NORTHERN IOWA MAY HAVE
DENSE FOG DEVELOP FRIDAY NIGHT AND MAY NOT HAVE MUCH IMPROVEMENT
THROUGH SUNDAY. MORE WIDESPREAD AREAS OF DRIZZLE ARE EXPECTED TO
DEVELOP LATE SATURDAY THROUGH SUNDAY. THE DRIZZLE WILL BE HEAVY
ENOUGH FOR SOME ACCUMULATIONS THROUGH THIS PERIOD. HAVE REMOVED
RAIN MENTION THROUGH SUNDAY WITH THE MID LEVELS REMAINING QUITE
DRY HOWEVER STILL EXPECTING A DREARY DAY WITH DRIZZLE AND FOG.
SOME POTENTIAL FOR SOUTHERN IOWA TO HAVE A PERIOD OF SUN ON
SATURDAY AND SUNDAY. IF THAT OCCURS...CERTAINLY COULD HAVE EVEN
WARMER TEMPERATURES. DEWPOINTS BY SATURDAY NIGHT INTO SUNDAY WILL
RISE INTO THE 40S TO EVEN 50S OVER THE SOUTH THUS AGAIN OVERNIGHT
TEMPERATURES WILL BE STEADY TO SLOWLY RISING.
THE THERMAL RIDGE WILL BEGIN TO DEGRADE BY LATE SUNDAY AS AN UPPER
LOW APPROACHES FROM THE SOUTHWEST AND ANOTHER UPPER LEVEL SYSTEM
DROPS INTO SOUTH CENTRAL CANADA. LEE SIDE CYCLOGENESIS WILL
COMMENCE OVER SOUTHEAST COLORADO AND THE OKLAHOMA/TEXAS PANHANDLES
ON SUNDAY. THIS LOW PRESSURE SYSTEM IS EXPECTED TO IMPACT IOWA
MONDAY THROUGH TUESDAY. STILL A LOT OF GUIDANCE VARIABILITY TO THE
TRACK OF THE LOW PRESSURE WITH THE 12Z ECMWF MUCH FARTHER NORTH
THAN PREVIOUS RUNS. THE SYSTEM MOVING SOUTH FROM SOUTH CENTRAL
CANADA WILL CONTINUE TO SQUASH THE UPPER RIDGE AND WILL LIMIT THE
AMOUNT OF NORTHEAST CURVATURE POTENTIAL FOR THE UPPER LEVEL SYSTEM
AND ITS SURFACE REFLECTION. THIS WOULD FAVOR THE MORE SOUTHERLY
SOLUTIONS WITH THE GFS AND ITS ENSEMBLE MEAN SOLUTION A GOOD
MEDIUM AND PREFERRED. MIXED PHASE PRECIPITATION IS LIKELY AS THE
COOLER AIR MOVES IN FROM THE WEST/NW AND DO NOT EXPECT A STRAIGHT
RAIN TO SNOW TRANSITION. LIKELY TO HAVE A BRIEF PERIOD OF FREEZING
RAIN AND SLEET IN BETWEEN LATE MONDAY OVER THE NORTHWEST THEN
ACROSS THE ENTIRE AREA MONDAY NIGHT. SNOW LIKELY WILL LINGER INTO
TUESDAY BEFORE THE SYSTEM DEPARTS. COULD MEET WINTER HEADLINE
CRITERIA OVER PORTIONS OF CENTRAL AND NORTHWEST IOWA AND WILL
CONTINUE TO HIGHLIGHT THE POTENTIAL IN THE HWO. SEASONAL
TEMPERATURES WITH NO SIGNIFICANT WEATHER IS FORECAST WEDNESDAY AND
THURSDAY.
&&
.AVIATION...11/18Z
ISSUED AT 1128 AM CST THU DEC 11 2014
A VERY STEEP INVERSION WILL KEEP LOW LEVEL MOISTURE IN PLACE FOR
THE FORESEEABLE FUTURE THUS EXPECT LOW MVFR TO IFR CIGS AND VSBYS
THROUGH THE FORECAST PERIOD. THERE MAY BE A COUPLE PERIODS WHERE A
SLIGHT IMPROVEMENT OCCURS BUT FOR THAT WILL NOT BE THE RULE.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...DONAVON
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1251 PM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 1247 PM CST THU DEC 11 2014
THE WEAK DECEMBER SUN HAS MANAGED TO BREAK UP THE 1 KFT THICK
CLOUD LAYER ACROSS THE AREA. THE CLEARING WILL ALSO ALLOW
TEMPERATURES TO CLIMB A BIT MORE AS WELL. CLOUDS SHOULD BEGIN
REDEVELOPING BY LATE AFTERNOON WITH A TREND TOWARD CLOUDY
CONDITIONS BY OR SHORTLY AFTER SUNSET...SIMILAR TO YESTERDAY. THUS
THE FORECAST HAS BEEN UPDATED TO RAISE TEMPERATURES AND REDUCE
CLOUD COVER THROUGH MID AFTERNOON.
UPDATE ISSUED AT 1037 AM CST THU DEC 11 2014
PER AIRCRAFT REPORTS THE CLOUD DECK IS ROUGHLY 1 KFT THICK.
HOWEVER...TRENDS FROM THE RAP INDICATE THE STRENGTH OF THE
INVERSION WILL INCREASE AS THE DAY PROGRESSES.
THEREFORE THE FORECAST HAS BEEN UPDATED TO LOWER MAX TEMPERATURES
SEVERAL DEGREES AND TO GO WITH COMPLETELY CLOUDY SKIES. A THINNING
IN SATELLITE MOVING EAST ACROSS IOWA MAY ALLOW A VERY BRIEF PEEK
OF FILTERED SUN BUT IT WILL BE EXCEEDINGLY BRIEF.
A REPORT OF A VERY FINE SNOW/DRIZZLE MIX FROM THE ALTOONA AREA
SUGGESTS THE POTENTIAL OF SOME EXTREMELY ISOLATED FLURRIES/DRIZZLE
THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 305 AM CST THU DEC 11 2014
EXTENSIVE AREA OF STRATUS BLANKETS MUCH OF THE MIDWEST WITH ALL RAOBS
AT 00Z/11 INDICATING A STRONG INVERSION AT AROUND 900 MB TRAPPING THE
LOW LEVEL MOISTURE BELOW. HIGH PRESSURE AT THE SURFACE WAS PROVIDING
CALM WINDS WITH 3 AM TEMPERATURES IN THE DVN CWA IN THE 23 TO 30 RANGE.
ELSEWHERE...A MAJOR STORM SYSTEM WAS SLAMMING INTO THE PACIFIC NORTHWEST
AND INTO NORTHERN CA...WHILE ANOTHER LARGE STORM SYSTEM WAS CENTERED
OVER NEW ENGLAND. AN UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN
ROCKIES TO SOUTHWEST ONTARIO. GULF MOISTURE WAS RETURNING TO SOUTH
TX WHILE THE 850 MB +10C ISOTHERM EXTENDED FROM KBIS TO KFWD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST THU DEC 11 2014
FORECAST FOCUS ON CLOUDS AND TEMPERATURES.
PERSISTENCE FORECASTING SEEMS THE WAY TO GO IN THE SHORT TERM AS
HIGH PRESSURE AT THE SURFACE REMAINS LOCKED IN PLACE...KEEPING
WINDS LIGHT TO CALM. FORECAST SOUNDINGS INDICATE THE STRONG
INVERSION TO REMAIN AS WARMING OCCURS ALOFT WHICH WILL KEEP THE
STRATUS TRAPPED UNDER THE INVERSION. THERE MAY BE SOME BRIEF SMALL
BREAKS IN THE OVERCAST BUT FOR THE MOST PART THIS IS A CLOUDY FORECAST.
GUIDANCE REALLY STRUGGLING WITH THE CLOUDS WITH THE MAV THE WORST
SHOWING CLEAR SKIES THROUGH THIS PERIOD. AT LEAST THE MET IS SOMEWHAT
CLOSER TO REALITY. AS FAR AS TEMPERATURES ARE CONCERNED THIS MAKES
THE MAV GUIDANCE UNRELIABLE (MAXES TOO WARM/MINS TOO COLD) WITH THE
MET BETTER IN SHOWING A SMALLER DIURNAL TREND DUE TO CLOUD COVER.
BOTTOM LINE IS I WILL FORECAST MAXIMUM TEMPERATURES TODAY IN THE
LOWER TO MID 30S...WITH LOWS TONIGHT 25 TO 30. ONCE AGAIN PERSISTENCE
FORECASTING APPEARS TO BE THE NAME OF THE GAME. WITH HIGH PRESSURE
OVER THE AREA AND MOISTURE QUITE SHALLOW POPS WILL BE ZERO.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 305 AM CST THU DEC 11 2014
OVERVIEW...A LARGE UPPER-LEVEL LOW SPINNING OVER THE NE U.S...HAS
SET UP A BLOCKING PATTERN ACROSS THE MIDWEST FORCING MAIN UPPER JET
FROM THE WEST COAST NORTHEASTWARD INTO WESTERN AND NORTHERN CANADA.
CONSEQUENTLY...SFC LOW PRESSURE WILL REMAIN ORGANIZED OVER WESTERN
PART OF NORTH AMERICA ALLOWING SOUTHERLY FLOW TO DEVELOP ACROSS THE
CENTRAL U.S. SFC TEMPS WILL PEAK INTO THE 50S FOR THE UPCOMING
WEEKEND AS THE 500 MB RIDGE AXIS ALIGNS WITH THE MISSISSIPPI VALLEY
REGION AND SOUTHERLY WINDS ADVECT 850 MB TO AROUND +10 C.
FRIDAY...FORECAST SOUNDINGS HAVE SATURATED LAYER BETWEEN 925-950 MB
WHICH MEANS STUBBORN STRATUS DECK WILL CONTINUE TO HOLD TEMPS DOWN.
HIGHS ARE FORECAST NEAR 40 F WITH MID 40S FAR SOUTHERN CWA THANKS TO
STEADY SOUTHERLY FLOW. 850 MB TEMPS NUDGING CLOSE TO +10 C WILL BE A
SIGN OF A SIGNIFICANT PATTERN CHANGE TO COME.
SATURDAY AND SUNDAY...VERY MILD FOR MID DECEMBER. CURRENT FORECAST
HIGHS ARE MID TO UPPER 40S ACROSS THE NORTH TO MID 50S IN THE SOUTH
WITH 1000-500 MB THICKNESS PEAKING NEAR 560 DAM. THE STRENGTH OF THE
RIDGE IS QUITE IMPRESSIVE. THE NAEFS 500 MB HEIGHT RETURN INTERVAL
FORECAST...IS FOR HEIGHTS THIS ANOMALOUSLY HIGH (576 DAM NEAR THE
DVN CWA) TO OCCUR ABOUT ONCE EVERY 20-30 YEARS DURING MID DECEMBER.
CONTINUED LOW-LEVEL MOISTURE ADVECTION MAY EVENTUALLY RESULT IN
AREAS OF FOG/DZ ESPECIALLY LATER SUNDAY/SUNDAY NIGHT. NEGATIVE OMEGA
IS VIRTUALLY NONEXISTENT UNTIL LATER SUNDAY AFTN SO DZ/-RA CHANCES
WILL INCREASE AT THAT TIME.
MONDAY AND TUESDAY...ECMWF HAS UPPER JET AND MID-LEVEL VORTICITY MAX
TRACKING ACROSS N. ARKANSAS INTO TENNESSEE WHILE THE GFS IS FURTHER
NORTH ACROSS S. MISSOURI INTO INDIANA. EITHER WAY...THE BAROCLINIC
ZONE IS WEAK AND PRECIP IS RELATIVELY LIGHT AS IT MOVES THROUGH.
ECMWF FAVORS THE SOUTHERN HALF OF THE DVN CWA FOR THE STEADIER
-RA...THE GFS IS MORE UNIFORM ACROSS THE CWA. BOTH MODELS INDICATE
RAIN TO BE PREDOMINATE PRECIP TYPE. LITTLE TO NO MOISTURE IS LEFT BY
THE TIME THE COLUMN IS COLD ENOUGH FOR SNOW ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1122 AM CST THU DEC 11 2014
WIDESPREAD MVFR CONDITIONS WILL CONTINUE THROUGH 00Z/12 WITH A 1
KFT THICK CLOUD DECK TRAPPED UNDER AN INVERSION. AFTER 00Z/12
CONDITIONS WILL DETERIORATE TO WIDESPREAD IFR CONDITIONS WITH
POCKETS OF LIFR CONDITIONS POSSIBLE. ADDITIONAL LOW LEVEL MOISTURE
FLOWING INTO THE AREA MAY PRODUCE LIFR CONDITIONS THAT ARE MORE
WIDESPREAD PRIOR TO SUNRISE FRIDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...UTTECH
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1126 AM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 1037 AM CST THU DEC 11 2014
PER AIRCRAFT REPORTS THE CLOUD DECK IS ROUGHLY 1 KFT THICK.
HOWEVER...TRENDS FROM THE RAP INDICATE THE STRENGTH OF THE
INVERSION WILL INCREASE AS THE DAY PROGRESSES.
THEREFORE THE FORECAST HAS BEEN UPDATED TO LOWER MAX TEMPERATURES
SEVERAL DEGREES AND TO GO WITH COMPLETELY CLOUDY SKIES. A THINNING
IN SATELLITE MOVING EAST ACROSS IOWA MAY ALLOW A VERY BRIEF PEEK
OF FILTERED SUN BUT IT WILL BE EXCEEDINGLY BRIEF.
A REPORT OF A VERY FINE SNOW/DRIZZLE MIX FROM THE ALTOONA AREA
SUGGESTS THE POTENTIAL OF SOME EXTREMELY ISOLATED FLURRIES/DRIZZLE
THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 305 AM CST THU DEC 11 2014
EXTENSIVE AREA OF STRATUS BLANKETS MUCH OF THE MIDWEST WITH ALL RAOBS
AT 00Z/11 INDICATING A STRONG INVERSION AT AROUND 900 MB TRAPPING THE
LOW LEVEL MOISTURE BELOW. HIGH PRESSURE AT THE SURFACE WAS PROVIDING
CALM WINDS WITH 3 AM TEMPERATURES IN THE DVN CWA IN THE 23 TO 30 RANGE.
ELSEWHERE...A MAJOR STORM SYSTEM WAS SLAMMING INTO THE PACIFIC NORTHWEST
AND INTO NORTHERN CA...WHILE ANOTHER LARGE STORM SYSTEM WAS CENTERED
OVER NEW ENGLAND. AN UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN
ROCKIES TO SOUTHWEST ONTARIO. GULF MOISTURE WAS RETURNING TO SOUTH
TX WHILE THE 850 MB +10C ISOTHERM EXTENDED FROM KBIS TO KFWD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST THU DEC 11 2014
FORECAST FOCUS ON CLOUDS AND TEMPERATURES.
PERSISTENCE FORECASTING SEEMS THE WAY TO GO IN THE SHORT TERM AS
HIGH PRESSURE AT THE SURFACE REMAINS LOCKED IN PLACE...KEEPING
WINDS LIGHT TO CALM. FORECAST SOUNDINGS INDICATE THE STRONG
INVERSION TO REMAIN AS WARMING OCCURS ALOFT WHICH WILL KEEP THE
STRATUS TRAPPED UNDER THE INVERSION. THERE MAY BE SOME BRIEF SMALL
BREAKS IN THE OVERCAST BUT FOR THE MOST PART THIS IS A CLOUDY FORECAST.
GUIDANCE REALLY STRUGGLING WITH THE CLOUDS WITH THE MAV THE WORST
SHOWING CLEAR SKIES THROUGH THIS PERIOD. AT LEAST THE MET IS SOMEWHAT
CLOSER TO REALITY. AS FAR AS TEMPERATURES ARE CONCERNED THIS MAKES
THE MAV GUIDANCE UNRELIABLE (MAXES TOO WARM/MINS TOO COLD) WITH THE
MET BETTER IN SHOWING A SMALLER DIURNAL TREND DUE TO CLOUD COVER.
BOTTOM LINE IS I WILL FORECAST MAXIMUM TEMPERATURES TODAY IN THE
LOWER TO MID 30S...WITH LOWS TONIGHT 25 TO 30. ONCE AGAIN PERSISTENCE
FORECASTING APPEARS TO BE THE NAME OF THE GAME. WITH HIGH PRESSURE
OVER THE AREA AND MOISTURE QUITE SHALLOW POPS WILL BE ZERO.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 305 AM CST THU DEC 11 2014
OVERVIEW...A LARGE UPPER-LEVEL LOW SPINNING OVER THE NE U.S...HAS
SET UP A BLOCKING PATTERN ACROSS THE MIDWEST FORCING MAIN UPPER JET
FROM THE WEST COAST NORTHEASTWARD INTO WESTERN AND NORTHERN CANADA.
CONSEQUENTLY...SFC LOW PRESSURE WILL REMAIN ORGANIZED OVER WESTERN
PART OF NORTH AMERICA ALLOWING SOUTHERLY FLOW TO DEVELOP ACROSS THE
CENTRAL U.S. SFC TEMPS WILL PEAK INTO THE 50S FOR THE UPCOMING
WEEKEND AS THE 500 MB RIDGE AXIS ALIGNS WITH THE MISSISSIPPI VALLEY
REGION AND SOUTHERLY WINDS ADVECT 850 MB TO AROUND +10 C.
FRIDAY...FORECAST SOUNDINGS HAVE SATURATED LAYER BETWEEN 925-950 MB
WHICH MEANS STUBBORN STRATUS DECK WILL CONTINUE TO HOLD TEMPS DOWN.
HIGHS ARE FORECAST NEAR 40 F WITH MID 40S FAR SOUTHERN CWA THANKS TO
STEADY SOUTHERLY FLOW. 850 MB TEMPS NUDGING CLOSE TO +10 C WILL BE A
SIGN OF A SIGNIFICANT PATTERN CHANGE TO COME.
SATURDAY AND SUNDAY...VERY MILD FOR MID DECEMBER. CURRENT FORECAST
HIGHS ARE MID TO UPPER 40S ACROSS THE NORTH TO MID 50S IN THE SOUTH
WITH 1000-500 MB THICKNESS PEAKING NEAR 560 DAM. THE STRENGTH OF THE
RIDGE IS QUITE IMPRESSIVE. THE NAEFS 500 MB HEIGHT RETURN INTERVAL
FORECAST...IS FOR HEIGHTS THIS ANOMALOUSLY HIGH (576 DAM NEAR THE
DVN CWA) TO OCCUR ABOUT ONCE EVERY 20-30 YEARS DURING MID DECEMBER.
CONTINUED LOW-LEVEL MOISTURE ADVECTION MAY EVENTUALLY RESULT IN
AREAS OF FOG/DZ ESPECIALLY LATER SUNDAY/SUNDAY NIGHT. NEGATIVE OMEGA
IS VIRTUALLY NONEXISTENT UNTIL LATER SUNDAY AFTN SO DZ/-RA CHANCES
WILL INCREASE AT THAT TIME.
MONDAY AND TUESDAY...ECMWF HAS UPPER JET AND MID-LEVEL VORTICITY MAX
TRACKING ACROSS N. ARKANSAS INTO TENNESSEE WHILE THE GFS IS FURTHER
NORTH ACROSS S. MISSOURI INTO INDIANA. EITHER WAY...THE BAROCLINIC
ZONE IS WEAK AND PRECIP IS RELATIVELY LIGHT AS IT MOVES THROUGH.
ECMWF FAVORS THE SOUTHERN HALF OF THE DVN CWA FOR THE STEADIER
-RA...THE GFS IS MORE UNIFORM ACROSS THE CWA. BOTH MODELS INDICATE
RAIN TO BE PREDOMINATE PRECIP TYPE. LITTLE TO NO MOISTURE IS LEFT BY
THE TIME THE COLUMN IS COLD ENOUGH FOR SNOW ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1122 AM CST THU DEC 11 2014
WIDESPREAD MVFR CONDITIONS WILL CONTINUE THROUGH 00Z/12 WITH A 1
KFT THICK CLOUD DECK TRAPPED UNDER AN INVERSION. AFTER 00Z/12
CONDITIONS WILL DETERIORATE TO WIDESPREAD IFR CONDITIONS WITH
POCKETS OF LIFR CONDITIONS POSSIBLE. ADDITIONAL LOW LEVEL MOISTURE
FLOWING INTO THE AREA MAY PRODUCE LIFR CONDITIONS THAT ARE MORE
WIDESPREAD PRIOR TO SUNRISE FRIDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...UTTECH
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1043 AM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 1037 AM CST THU DEC 11 2014
PER AIRCRAFT REPORTS THE CLOUD DECK IS ROUGHLY 1 KFT THICK.
HOWEVER...TRENDS FROM THE RAP INDICATE THE STRENGTH OF THE
INVERSION WILL INCREASE AS THE DAY PROGRESSES.
THEREFORE THE FORECAST HAS BEEN UPDATED TO LOWER MAX TEMPERATURES
SEVERAL DEGREES AND TO GO WITH COMPLETELY CLOUDY SKIES. A THINNING
IN SATELLITE MOVING EAST ACROSS IOWA MAY ALLOW A VERY BRIEF PEEK
OF FILTERED SUN BUT IT WILL BE EXCEEDINGLY BRIEF.
A REPORT OF A VERY FINE SNOW/DRIZZLE MIX FROM THE ALTOONA AREA
SUGGESTS THE POTENTIAL OF SOME EXTREMELY ISOLATED FLURRIES/DRIZZLE
THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 305 AM CST THU DEC 11 2014
EXTENSIVE AREA OF STRATUS BLANKETS MUCH OF THE MIDWEST WITH ALL RAOBS
AT 00Z/11 INDICATING A STRONG INVERSION AT AROUND 900 MB TRAPPING THE
LOW LEVEL MOISTURE BELOW. HIGH PRESSURE AT THE SURFACE WAS PROVIDING
CALM WINDS WITH 3 AM TEMPERATURES IN THE DVN CWA IN THE 23 TO 30 RANGE.
ELSEWHERE...A MAJOR STORM SYSTEM WAS SLAMMING INTO THE PACIFIC NORTHWEST
AND INTO NORTHERN CA...WHILE ANOTHER LARGE STORM SYSTEM WAS CENTERED
OVER NEW ENGLAND. AN UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN
ROCKIES TO SOUTHWEST ONTARIO. GULF MOISTURE WAS RETURNING TO SOUTH
TX WHILE THE 850 MB +10C ISOTHERM EXTENDED FROM KBIS TO KFWD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST THU DEC 11 2014
FORECAST FOCUS ON CLOUDS AND TEMPERATURES.
PERSISTENCE FORECASTING SEEMS THE WAY TO GO IN THE SHORT TERM AS
HIGH PRESSURE AT THE SURFACE REMAINS LOCKED IN PLACE...KEEPING
WINDS LIGHT TO CALM. FORECAST SOUNDINGS INDICATE THE STRONG
INVERSION TO REMAIN AS WARMING OCCURS ALOFT WHICH WILL KEEP THE
STRATUS TRAPPED UNDER THE INVERSION. THERE MAY BE SOME BRIEF SMALL
BREAKS IN THE OVERCAST BUT FOR THE MOST PART THIS IS A CLOUDY FORECAST.
GUIDANCE REALLY STRUGGLING WITH THE CLOUDS WITH THE MAV THE WORST
SHOWING CLEAR SKIES THROUGH THIS PERIOD. AT LEAST THE MET IS SOMEWHAT
CLOSER TO REALITY. AS FAR AS TEMPERATURES ARE CONCERNED THIS MAKES
THE MAV GUIDANCE UNRELIABLE (MAXES TOO WARM/MINS TOO COLD) WITH THE
MET BETTER IN SHOWING A SMALLER DIURNAL TREND DUE TO CLOUD COVER.
BOTTOM LINE IS I WILL FORECAST MAXIMUM TEMPERATURES TODAY IN THE
LOWER TO MID 30S...WITH LOWS TONIGHT 25 TO 30. ONCE AGAIN PERSISTENCE
FORECASTING APPEARS TO BE THE NAME OF THE GAME. WITH HIGH PRESSURE
OVER THE AREA AND MOISTURE QUITE SHALLOW POPS WILL BE ZERO.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 305 AM CST THU DEC 11 2014
OVERVIEW...A LARGE UPPER-LEVEL LOW SPINNING OVER THE NE U.S...HAS
SET UP A BLOCKING PATTERN ACROSS THE MIDWEST FORCING MAIN UPPER JET
FROM THE WEST COAST NORTHEASTWARD INTO WESTERN AND NORTHERN CANADA.
CONSEQUENTLY...SFC LOW PRESSURE WILL REMAIN ORGANIZED OVER WESTERN
PART OF NORTH AMERICA ALLOWING SOUTHERLY FLOW TO DEVELOP ACROSS THE
CENTRAL U.S. SFC TEMPS WILL PEAK INTO THE 50S FOR THE UPCOMING
WEEKEND AS THE 500 MB RIDGE AXIS ALIGNS WITH THE MISSISSIPPI VALLEY
REGION AND SOUTHERLY WINDS ADVECT 850 MB TO AROUND +10 C.
FRIDAY...FORECAST SOUNDINGS HAVE SATURATED LAYER BETWEEN 925-950 MB
WHICH MEANS STUBBORN STRATUS DECK WILL CONTINUE TO HOLD TEMPS DOWN.
HIGHS ARE FORECAST NEAR 40 F WITH MID 40S FAR SOUTHERN CWA THANKS TO
STEADY SOUTHERLY FLOW. 850 MB TEMPS NUDGING CLOSE TO +10 C WILL BE A
SIGN OF A SIGNIFICANT PATTERN CHANGE TO COME.
SATURDAY AND SUNDAY...VERY MILD FOR MID DECEMBER. CURRENT FORECAST
HIGHS ARE MID TO UPPER 40S ACROSS THE NORTH TO MID 50S IN THE SOUTH
WITH 1000-500 MB THICKNESS PEAKING NEAR 560 DAM. THE STRENGTH OF THE
RIDGE IS QUITE IMPRESSIVE. THE NAEFS 500 MB HEIGHT RETURN INTERVAL
FORECAST...IS FOR HEIGHTS THIS ANOMALOUSLY HIGH (576 DAM NEAR THE
DVN CWA) TO OCCUR ABOUT ONCE EVERY 20-30 YEARS DURING MID DECEMBER.
CONTINUED LOW-LEVEL MOISTURE ADVECTION MAY EVENTUALLY RESULT IN
AREAS OF FOG/DZ ESPECIALLY LATER SUNDAY/SUNDAY NIGHT. NEGATIVE OMEGA
IS VIRTUALLY NONEXISTENT UNTIL LATER SUNDAY AFTN SO DZ/-RA CHANCES
WILL INCREASE AT THAT TIME.
MONDAY AND TUESDAY...ECMWF HAS UPPER JET AND MID-LEVEL VORTICITY MAX
TRACKING ACROSS N. ARKANSAS INTO TENNESSEE WHILE THE GFS IS FURTHER
NORTH ACROSS S. MISSOURI INTO INDIANA. EITHER WAY...THE BAROCLINIC
ZONE IS WEAK AND PRECIP IS RELATIVELY LIGHT AS IT MOVES THROUGH.
ECMWF FAVORS THE SOUTHERN HALF OF THE DVN CWA FOR THE STEADIER
-RA...THE GFS IS MORE UNIFORM ACROSS THE CWA. BOTH MODELS INDICATE
RAIN TO BE PREDOMINATE PRECIP TYPE. LITTLE TO NO MOISTURE IS LEFT BY
THE TIME THE COLUMN IS COLD ENOUGH FOR SNOW ON TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 530 AM CST THU DEC 11 2014
PERSISTENT LOW STRATUS CLOUDS WILL CONTINUE THROUGH THIS TAF
PERIOD AS SUBSIDENCE INVERSION STRENGTHENS. EXPECT MVFR FOR CIGS
NEAR 1500 FT AGL THIS MORNING LOWERING TO IFR AS EARLY AS THE LATE
MORNING AT KDBQ AND BY THE EVENING AT KCID AND KMLI. THERE IS ALSO
THE POTENTIAL FOR PATCHY FOG DEVELOPMENT TONIGHT SO HAVE VSBYS
DROPPING TO MVFR AT ALL TERMINALS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...UTTECH
AVIATION...UTTECH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
254 PM CST Thu Dec 11 2014
.SHORT TERM...(This Evening through Friday)
Issued at 252 PM CST THU DEC 11 2014
20Z water vapor imagery shows a mid level ridge from the southern
Rockies into the northern plains. A weak shortwave was noted moving
south over the area on the back side of the closed low over the
northeast. However there is not much deep layer vertical motion with
this wave as indicated by the persistent stratus deck trapped within
a low level inversion. At the surface, ridging over the MS river
valley and low pressure along the lee of the Rockies has formed a
favorable pattern for gulf moisture to return north. This is also
aiding in the persistence of the low clouds and mist.
For tonight and Friday, models show little change in the pattern
with low level moisture continuing to advect north into the area.
Additionally weak subsidence on the back side of the shortwave aloft
is likely to reinforce the low level inversion through the day Friday
making it unlikely the boundary layer will mix out. Therefore the
forecast is for continued dreary weather. The NAM and RAP show low
level isentropic upglide redeveloping early this evening. Because of
this think areas of mist and drizzle are likely to redevelop. The
good news with all of this is temperatures are not expected to cool
much if any tonight due to a lack of radiational cooling and
continued low level moisture and warm air advection. The forecast
has temps pretty much holding steady in the upper 30s to around 40.
So the weather is expected to have little impact to daily activities
and the only impact of concern may be some restricted visibilities
from fog. However think that widespread dense fog will be mitigated
by the stratus already in place. Have been conservative with highs
Friday expecting overcast skies to hold strong. Although southerly
winds and warm air advection should help warm temps into the lower
50s.
.LONG TERM...(Friday Night through Thursday)
Issued at 252 PM CST THU DEC 11 2014
Low level moisture advection increases northward Friday evening as
high pressure shifts east. Surface trough develops over the
Rockies resulting in increasing winds around 10 to 15 mph during the
afternoon Saturday. Winds do not appear particularly strong enough
to overcome the persistent stratus deck, with increasing moisture
raising dewpoints into the lower 50s. Thermal ridge stretched from
western Texas through the Midwest advects h85 temps near 13C by
Sunday morning. Above normal highs remain on track with readings in
the upper 50s to low 60s this weekend. Insulation from the stratus
may keep lows near the record warm levels as overnight lows fall
into the upper 40s to lower 50s.
In terms of precipitation Saturday, forecast soundings show brief
periods of enhanced lift within the cloud deck where light drizzle
or rain showers are possible. Surface winds hold or increase
slightly Saturday evening into Sunday as the upper shortwave trough
deepens east towards the four corners region. Adjusted precip
chances for rainfall Sunday afternoon as latest guidance is trending
the upper trough a tad slower, arriving in the late afternoon across
north central areas...spreading into all of northeast Kansas during
the evening. Bulk of the light to moderate rainfall exits by Monday
morning while models still hint at an enhanced deformation zone
setting up over eastern Nebraska and the northern half of the CWA.
There is some uncertainty on guidance as latest runs remain in
disagreement on the track of the upper trough and therefore how far
south additional precip occurs on Monday. At this time, held highest
chances north of Interstate 70 where falling temps Monday afternoon
and evening may switch rain over to a rain and snow mix. Rainfall
accumulations by the end of the event may range from a quarter up to
an inch for most locations. Accumulating snowfall is not anticipated
as below freezing temps do not arrive until after precipitation
exits.
Surface high pressure builds into the area Tuesday and Wednesday
where our best bet for sunny skies exists. Temperatures fall back to
more seasonal values with highs in the 40s and lows in the 20s and
30s. This pattern unfortunately does not last long as stratus
returns with the amplification of a slow-moving longwave trough
developing to the southwest. Vorticity maxima embedded within the
mean flow ejects into the central plains Wednesday evening and Thursday.
Much uncertainty remains with this system however the cooler airmass
in place hints at a possible rain and snow mix for much of the area
during this time. This system is not notably strong but will
continue to watch trends in upcoming days.
&&
.AVIATION...(For the 18Z TAFs through 18Z Friday Afternoon)
Issued at 1112 AM CST THU DEC 11 2014
12Z model runs do not show much hope for improvement from the IFR
and LIFR conditions as a low sun angle and lack of insolation make
it difficult to mix out the boundary layer. With the surface
ridge axis to the east and winds gradually veering, low level
moisture is progged to continue to advect north. The forecast is
based on persistence and recent history and think that as the
inversion strengthens this evening that isentropic upglide within
the weak low level warm air advection pattern will lead to areas
of drizzle and fog once again.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...67
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1112 AM CST Thu Dec 11 2014
...AVIATION UPDATE...
.UPDATE...
Issued at 927 AM CST THU DEC 11 2014
Did a quick update to maintain overcast skies through the day. RAP
forecast soundings fail to mix out the boundary layer and maintain
the low level saturation through the day. Given the expanse of the
low level stratus, think it is more likely for the clouds to
remain in place than the chance to see the sun this afternoon.
Also the RAP and NAM keep some hint of weak isentropic upglide
through the afternoon along and south of I-70. This could aid in
keeping a light mist or drizzle going into the afternoon. Have not
done anything with afternoon highs since winds still appear to
veer to the southeast with a chance for some warm air advection.
If surface winds remain out of the east, forecast highs may be a
little optimistic.
&&
.SHORT TERM...(Today and Tonight)
Issued at 331 AM CST THU DEC 11 2014
Northerly flow aloft was in place across the central U.S. as a
strong closed-off low was centered over the New England area and a ridge
axis was situated over the Rockies. Water vapor imagery showed a
weak embedded shortwave over Kansas that was slowly sliding
southeastward. Some isentropic lift on the 290K-300K surface was
noted with this shortwave. This lift combined with continued
low-level saturation resulted in areas of drizzle developing early
this morning across much of the southeastern two-thirds of the forecast
area. With temperatures holding fairly steady around 34F-35F and
dewpoint temperatures generally around 33F-34F, do not anticipate
wet-bulb cooling to drop temperatures below freezing in this region
so expect this light precipitation to stay in the form of drizzle.
The only area worth watching is across far northeast Kansas along
the Kansas/Nebraska border where surface and dewpoint temperatures
are a couple of degrees cooler. If any of this drizzle were to
extend that far north then some light freezing drizzle and some
resultant slick spots on the roadways would be possible. In addition
to the drizzle, this low-level saturation combined with light
easterly winds due to the surface high located just east of the area
will result in areas of fog remaining in place across the forecast
area through mid to late morning.
Expect these areas of drizzle to persist through the morning hours,
but model soundings show some dry air working into the area just
above the surface by this afternoon so may see a brief break in the
drizzle. While the cloud cover may thin out some across north
central Kansas, still expect overcast skies to prevail through the
day with light southeasterly winds helping to boost afternoon
temperatures a few degrees warmer than yesterday, into the low 40s.
Model soundings show the dry air just above the surface becoming
saturated once again and should keep this low-level saturation in
place through the overnight hours tonight. As a result, expect areas
of drizzle to develop once again along with areas of fog, especially
across far northern Kansas near the Kansas/Nebraska border. With
overcast skies in place and winds veering more toward the
south-southeast, overnight low temperatures should only drop into
the mid 30s to around 40 degrees from north to south. As a result,
this very light precipitation should stay in the form of light
drizzle.
.LONG TERM...(Friday through Wednesday)
Issued at 331 AM CST THU DEC 11 2014
A deepening upper level trough will move off the eastern Pacific and
into the western CONUS Friday and Saturday resulting in a ridge
building across the Plains. Southerly flow will commence ahead of
the approaching system along with a moderation in temperatures
through the weekend. Forecast sounding continue to show the low
level moisture will continue in the low levels and increase in
depth. Also temperatures through the column continue to warm with
temps reaching around 11 Celsius at 850 MB on Saturday. Temperatures
will warm into the 50s Friday and Saturday with some 60s on Sunday
in the warm advection pattern.
On Friday will continue to see areas of drizzle and fog especially
in the morning when there is upward vertical motion in the moist
layer, however by afternoon the lift decreases and expect cloudy
skies to continue through the afternoon and early evening before the
next round of drizzle and fog develops Friday night and early
Saturday. The clouds will keep temperatures from falling much
overnight with lows in the 40s Saturday morning and in the 50s
Sunday morning.
There is still discrepancy between the models with the handling of
the upper trough moving through the Plains late in the weekend into
Monday. The GFS is faster than the GEM and ECMWF and is also a
little further north. Have continued to lean in the direction of the
ECMWF and the ECMWF mean as well as the GEM which are in closer
agreement. This will affect how quickly cold air will arrive for any
change over or mix with snow. The colder air looks to hold off in
the north central Kansas counties of the forecast area until the
latter part of the day on Monday. With a good conveyor of moisture
around the upper level system, the deformation zone sets up across
the forecast Sunday night and Monday which will yield moderate
rainfall amounts. Some areas could see 1+ inches. Have removed
mention of thunderstorms for Sunday afternoon as elevated
instability is forecast to be southwest of the forecast area.
The upper trough moves out Monday night with the cold air
overspreading the rest of the forecast area. Currently will continue
with a rain and snow mix, but areas in north central Kansas and near
the Nebraska border may change over to all snow before precipitation
ends. Little accumulation of wintry precipitation is expected at
this time. Dry weather is expected for Tuesday and Wednesday with
highs in the 30s and lows in the 20s. Another storm system will move
across the western CONUS Wednesday with precipitation developing
over the forecast area Wednesday night as energy ejects out into the
Plains.
&&
.AVIATION...(For the 18Z TAFs through 18Z Friday Afternoon)
Issued at 1112 AM CST THU DEC 11 2014
12Z model runs do not show much hope for improvement from the IFR
and LIFR conditions as a low sun angle and lack of insolation make
it difficult to mix out the boundary layer. With the surface
ridge axis to the east and winds gradually veering, low level
moisture is progged to continue to advect north. The forecast is
based on persistence and recent history and think that as the
inversion strengthens this evening that isentropic upglide within
the weak low level warm air advection pattern will lead to areas
of drizzle and fog once again.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...Wolters
SHORT TERM...Hennecke
LONG TERM...53
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS JACKSON KY
117 PM EST THU DEC 11 2014
.UPDATE...
ISSUED AT 117 PM EST THU DEC 11 2014
CLOUDS HAVE ENTIRELY DRIED UP...AND HAVE UPDATED THE FORECAST TO GO
WITH SUNNY FOR THE REST OF THE AFTERNOON. TEMPS LOOK ON TRACK.
UPDATE ISSUED AT 1001 AM EST THU DEC 11 2014
UPDATED THE SKY GRIDS BASED ON LATEST MODEL RUNS AND TRENDS IN
SATELLITE IMAGERY. CLEARING SHOULD PROGRESS THROUGH THE REMAINDER OF
THE AREA DURING THE DAY...WITH CLEAR OR MOSTLY CLEAR SKIES THEN
PERSISTING THROUGH FRIDAY.
UPDATE ISSUED AT 620 AM EST THU DEC 11 2014
DID A QUICK TOUCH UP ON THE HOURLY T/TD AND SKY GRIDS TO REFLECT THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM EST THU DEC 11 2014
07Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING INTO KENTUCKY...THOUGH
A LAYER OF STRATOCU CLOUDS REMAIN...BLANKETING THE CWA AND KEEPING
TEMPERATURES FROM FALLING OFF TOO FAST THIS NIGHT. READINGS AT 2 AM
VARIED FROM THE UPPER 20S ON THE RIDGES TO THE LOWER 30S IN THE
VALLEYS WHILE DEW POINTS HAD FALLEN TO THE LOWER 20S FOR MOST OF THE
AREA. CAA CONTINUES ON NORTH TO NORTHWEST WINDS OF 5 TO 10 KTS...WITH
A COUPLE OF HIGHER GUSTS NOTED ON THE RIDGES.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT FOR THE SHORT TERM
PORTION OF THE FORECAST AS THEY ALL DEPICT THE BLOCKING LOW IN PLACE
OVER SOUTHERN NEW ENGLAND ONLY SLOWLY PIVOTING AWAY TO THE NORTHEAST
THROUGH THE PERIOD. LOCALLY...THIS WILL ALLOW HEIGHTS TO GRADUALLY
RISE OVER EASTERN KENTUCKY...BUT NOT BEFORE ONE FINAL BATCH OF ENERGY
SHIFTS SOUTHEAST OF THE AREA THIS MORNING. OTHERWISE...A QUIET
PATTERN WILL ENSUE WITH LITTLE IN THE WAY OF ENERGY AFFECTING THE
STATE IN NORTH TO NORTHWEST FLOW LATER TODAY AND THROUGH THE DAY
FRIDAY. GIVEN THE MODEL AGREEMENT HAVE FOLLOWED THE HIGHER RESOLUTION
NAM12 AND HRRR MOST CLOSELY FOR WX DETAILS IN THE SHORT TERM.
THE MAIN QUESTION TODAY WILL BE HOW QUICKLY THE LOW CLOUDS IN PLACE
OVER THE AREA WILL BREAK UP. THE TIME HEIGHTS FROM THE NAM SUGGESTS
THAT THEY WOULD LINGER INTO THE AFTERNOON...HOWEVER...THE RECENT
SATELLITE LOOP SHOW CLEARING PUSHING QUICKLY SOUTH FROM NORTHERN
OHIO. ACCORDINGLY...HAVE BROUGHT THE LOWER PERCENTAGES OF CLOUD
COVER INTO EAST KENTUCKY A BIT SOONER THAN THE PREVIOUS FORECAST AND
THE NAM12 DEPICTION. OTHERWISE...MOSTLY CLEAR SKIES WILL BE THE RULE
THROUGH FRIDAY ONCE THAT DRIER AIR MOVES INTO THE CWA. THIS WILL LEAD
TO A SMALL TO MODERATE RIDGE TO VALLEY TEMPERATURE SPLIT TONIGHT...
WITH THE HIGH CENTER JUST TO THE WEST OF THE CWA. ONLY A SLOW
MODERATION OF THIS HIGH CAN BE EXPECTED SO HIGHS TODAY AND TOMORROW
WILL STILL BE ON THE CHILLY SIDE OF NORMAL...THOUGH FRIDAY WILL BE
SEVERAL DEGREES WARMER THAN TODAY WITH MORE SUNSHINE.
USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND GRIDS WITH
SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT. AS FOR POPS AND WX...
KEPT THEM LOW AND NON-EXISTENT THROUGH FRIDAY GIVEN THE HIGH PRESSURE
REGIME NOW IN PLACE...IN LINE WITH MOS GUIDANCE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 AM EST THU DEC 11 2014
THERE WAS GOOD MODEL AGREEMENT IN THE EXTENDED PORTION OF THE
FORECAST. BOTH THE GFS AND ECMWF BEGIN THE PERIOD WITH A LARGE RIDGE
OF HIGH PRESSURE SITUATED ACROSS A LARGE PORTION OF THE CENTRAL AND
EASTERN CONUS FROM FRIDAY NIGHT THROUGH MONDAY. THIS RIDGE LOOKS TO
BE QUITE STRONG AND THE MODELS DO NOT BEGIN MOVING IT OFF TO THE
EAST UNTIL MONDAY NIGHT...AS A FAIRLY WELL DEVELOPED AREA OF LOW
PRESSURE TAKES SHAPE OVER THE CENTRAL PLAINS. AS THIS SYSTEM BEGINS
TO MOVE EAST...THE RIDGE WILL FINALLY BEGIN TO GIVE GROUND AND MOVE
OFF TO OUR EAST AND EVENTUALLY THROUGH THE MID ATLANTIC REGION AND
OUT TO SEA BY EARLY TUESDAY MORNING. AS THE CENTRAL PLAINS
APPROACHES...CLOUD COVER WILL BE ON THE INCREASE MONDAY AFTERNOON
AND EVENING. TEMPERATURES WILL WARM UP QUITE NICELY ON MONDAY...AS
SOUTHERLY WINDS AHEAD OF THE APPROACHING SYSTEM BRING WARM MOIST AIR
OFF THE GULF OF MEXICO INTO THE REGION. BASED ON THE LATEST TIME
HEIGHT CROSS SECTIONS...IT APPEARS THAT PRECIPITATION ONSET WILL
HOLD UNTIL AROUND 0Z ON TUESDAY...OR UNTIL THE SHORTWAVE MOVES OUT
OF THE CENTRAL MISSISSIPPI VALLEY REGION AND ACROSS THE OHIO AND
TENNESSEE VALLEYS. THE WAVE LOOKS TO BE FAIRLY PROGRESSIVE...WITH
THE BEST CHANCES FOR RAIN OCCURRING MONDAY NIGHT AND TUESDAY.
UPSLOPE FLOW AND RESIDUAL MOISTURE BEHIND THE DEPARTING LOW WILL
KEEP A CHANCE OF SCATTERED RAIN SHOWERS IN THE FORECAST THROUGH
WEDNESDAY MORNING.
TEMPERATURES TO BEGIN THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL...WITH FORECAST HIGHS ON SATURDAY AND SUNDAY TOPPING OUT IN
THE MID 40S. MONDAY LOOKS TO BE WARMER THAN NORMAL IN THE RETURN
FLOW OFF THE GULF...WITH HIGHS ON MONDAY EXPECTED TO RISE INTO THE
LOW TO MID 50S ACROSS THE AREA. THE WEATHER WILL BE SLIGHTLY COOLER
ON TUESDAY DUE TO WIDESPREAD CLOUD COVER AND PRECIPITATION. HIGHS ON
MONDAY ARE EXPECTED TO TOP OUT AROUND 50. ONCE WINDS SHIFT TO THE
NORTHWEST BEHIND THE DEPARTING SYSTEM...COLDER AIR WILL BEGIN TO
SPILL INTO THE AREA...ALLOWING FOR HIGHS IN THE LOW TO MID 40S ON
WEDNESDAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 20S AND LOWER 30S
FRIDAY THROUGH SUNDAY NIGHT...BEFORE CLOUD COVER MOVES BACK IN AND
WINDS SHIFT TO THE SOUTH. THE MERCURY WILL NOT FALL AS MUCH MONDAY
NIGHT AND TUESDAY NIGHT DUE TO THE INFLUENCE OF CLOUD COVER AND
SOUTHERLY WINDS. LOWS THOSE TWO NIGHTS SHOULD ONLY FALL INTO THE
UPPER 30S FOR MOST FOLKS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 117 PM EST THU DEC 11 2014
VFR WILL PREVAIL THROUGH THE PERIOD. WINDS OUT OF THE WNW WILL GUST
AROUND 15 KTS IN OUR NORTHERN COUNTIES EARLY THIS AFTERNOON...BUT
WILL BE NEGLIGIBLE TONIGHT INTO FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1202 PM EST Thu Dec 11 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1042 AM EST Thu Dec 11 2014
Clearing over southern Michigan and much of eastern IN and Ohio has
worked southward into the eastern parts of the forecast area.
Partly sunny skies were noted in areas along and east of
I-65...while mostly cloudy skies lingered out across the west.
Expect more partial clearing to take place through the afternoon
hours, though our far western sections may end up staying mostly
cloudy for much of the day. While clearing has taken place this
morning, expect cold air stratocumulus to redevelop some, but
overall, partly sunny conditions should remain. Despite the
sunshine, temperatures will remain cold with highs topping out in
the upper 30s in the east with some lower 40s possible down across
the KY/TN border region.
Current forecast has this well in hand. However, we did adjust the
hourly temperatures and dewpoints slightly to better match up with
current observations. Also made some minor adjustments to the cloud
cover based on latest satellite imagery and trends.
.SHORT TERM (Now through Friday)...
Issued at 304 AM EST Thu Dec 11 2014
Clouds are again the main challenge with this forecast package.
Overcast conditions continued early this morning across southern
Indiana and central Kentucky. However, dry low level air was
punching from Quebec through Michigan into Indiana and Ohio on the
back side of cyclonic circulation over New England. By 3am the
clearing line had made it down to the I-70 corridor from
Indianapolis to Columbus. The HRRR has been doing the best job
overnight with this clearing line, with some support from 0.5km RH
progs from the GFS. These models bring the clearing line into
central and eastern parts of the LMK CWA over the course of the day,
and we`ll time it as such in the grids. West of I-65 is more of a
question mark, with models wanting to clear skies there as well but
satellite showing less clearing and more cloudiness upstream of
those areas. So, will hold on to the clouds longer in the west than
in the east.
High temperatures today should be around 40 degrees with northwest
breezes this morning becoming westerly this afternoon.
Tonight high pressure will build into the middle Mississippi and
lower Ohio Valleys. The models clear our skies out, which normally
makes sense with domes of high pressure. However, the high is
currently over the upper Mississippi Valley where it`s...cloudy.
So, there is some question whether or not we`ll really clear out
tonight. Even the wetter model solutions give us mostly clear
skies, though, so will lean on the side of fewer clouds for the
overnight hours at this time. It will be interesting to watch the
clouds to our northwest today to see if they slide southeast along
with the high or not. Big potential for a busted forecast tonight
re: sky cover.
Low temperatures tonight will depend a lot on how much cloud we end
up with. For now will stick with mid 20s. Warmer if we stay cloudy.
On Friday that high pressure system will be right on top of us,
giving us partly cloudy skies and high temperatures in the middle
and upper 40s with light winds.
.LONG TERM (Friday Night through Wednesday)...
Issued at 235 AM Thu Dec 11 2014
The upper level pattern by Friday night is expected remain highly
amplified across the CONUS, with a closed low across New England and
a deepening shortwave trough pushing into California. In between,
the blocking pattern will enhance the ridge through the central
Plains into southern Canada. At the surface, high pressure will
remain across the Mid-Mississippi and Ohio River Valleys.
Forecast challenge Friday night into Saturday is focused on cloud
cover and its impacts on temperatures. Despite very dry air above
850 mb, we`ll be dealing with some low-level moisture issues. 11.00z
guidance, particularly the NAM and GEM, suggest a strong inversion
sets up through about 925 mb, or the lowest 2500 ft, with increasing
saturation Friday night. A stratus deck would push into the region
from Upper MS River Valley based on model RH fields and would
persist through the day on Saturday. SREF probabilities for this
deck developing are currently running at or above 70 percent,
especially across the northern half of the local area. Models this
time of year struggle with low-level moisture, but given the
environmental setup, the fact that stratus is already present across
much of the central and northern Plains and the majority of the
models showing this solution, confidence is higher than average. As
such, increased cloud cover during this period and tempered the
diurnal temperature trend as well, favoring the warmer guidance for
Saturday morning lows and cooler guidance for highs.
Going into Sunday, clouds will once again be the main issue to deal
with across the Ohio Valley. Soundings differ in terms of the
strength, but all show the low level inversion remaining in place
around 925 mb, strongest along the KY/IN border and points north.
The surface high and upper level ridge axis are expected to be
directly over the region, resulting in an impressive light wind
layer /less than 10 kts through 25 kft/. If stratus is around, there
won`t be much wind to push/scour/mix it out. Again, increased cloud
cover some and lowered highs/raised lows, especially north of the KY
parkways.
By early next week, the major West Coast storm system will move
across the southern Plains and lift toward the Ohio Valley. The last
several cycles of model runs have shown high variability in the
track of this system, but the 11.00z runs seem to have come
together, bringing the system through Missouri and right across
KY/IN. Rain chances will spread in Monday, becoming likely Monday
night into Tuesday morning, then clearing out late Tuesday.
Confidence continues to increase, so POPs were adjusted higher. In
the wake of this system, a period of drier weather and seasonable
temperatures looks likely followed by the possibility of another
southern stream storm system for late next week into the following
weekend.
&&
.AVIATION (18Z TAF Update)...
Issued at 1202 PM EST Thu Dec 11 2014
Cloud deck continues to scour out from east to west this afternoon.
Most of the clearing has been east of a KSDF to KBWG line. However,
the clearing has been working westward with time and we should start
to see much of our CWA clearing out in the next few hours. VFR
conditions are expected at KSDF and KLEX this afternoon and tonight
as skies look to be mostly clear. A light northwest wind will be
seen this afternoon but will become light and variable this evening
and through the overnight period. At KBWG, we`ll continue to see
some MVFR ceilings for the next hour or so and then we should see
ceilings lift to VFR by 11/19Z. Mainly clear skies are expected
later this afternoon and tonight at KBWG with light and variable
winds.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........MJ
Short Term.....13
Long Term......ZBT
Aviation.......MJ
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
302 PM EST THU DEC 11 2014
.SYNOPSIS...
LOW PRESSURE WILL REMAIN OVER NEW ENGLAND INTO SATURDAY. HIGH
PRESSURE WILL BUILD OVER THE MID-ATLANTIC DURING THE WEEKEND BEFORE
MOVING OFF TO OUR EAST EARLY NEXT WEEK. LOW PRESSURE AND ITS
ASSOCIATED COLD FRONT WILL CROSS THE REGION TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 19Z...SPRAWLING LOW IS CENTERED OVER VT PER WATER VAPOR
IMAGERY. THE OCCLUSION HAS WRAPPED AROUND THIS AGING LOW AND ARCS
FROM NEWFOUNDLAND...LABRADOR...QUEBEC...LAKE ERIE...PA...AND ACROSS
THE CENTRAL MID-ATLANTIC. THE HRRR MODEL HAS DONE A GOOD JOB OF
HAVING SOME PRECIP OVER THE AREA...PARTICULARLY EAST OF DC TODAY.
HOWEVER...THE INTENSITY OF THE SNOW BAND WAS NOT PROGGED WELL.
DOWNSLOPING WLY FLOW WAS TO HAVE DIMINISHED THE SNOW AS IT MOVED
SOUTH FROM BALTIMORE. CONVERGENCE LED TO MODERATE SNOW OVER GREATER
BALTIMORE WHERE TEMPERATURES DROPPED TO AROUND FREEZING WITH A
COUPLE TENTHS INCH SNOWFALL PER WEB/TRAFFIC CAMS. A SECONDARY BAND
DROPPED SOUTH OF THE MASON-DIXON...BUT HAS MAINLY WEAKENED.
LIGHT SNOW AND FLURRIES WILL CONTINUE INTO THE EVENING OVER THE
EASTERN THIRD OF THE CWA (EAST FROM DC) AS DEEP FLOW BECOMES MORE
NWLY. TEMPERATURES WILL MODERATE A BIT IN THE REST OF THE AFTERNOON
AS ACCUMULATING PRECIP ENDS.
RIDGE OVER CNTRL CONUS CONTINUES TO SQUEEZE THE NEW ENGLAND LOW
TONIGHT...SHUNTING PRECIP EAST OF THE CWA. DRY CONDITIONS CAN THEN
BE EXPECTED THROUGH FRIDAY. NWLY FLOW CONTINUES TO GUST OVERNIGHT TO
AROUND 20 MPH...THEN 25 MPH FRIDAY. MIN TEMPS SUBFREEZING...
GENERALLY AROUND 30F. MAX FRIDAY A LITTLE WARMER THAN TODAY WITH
MORE SUN...LOW TO MID 40S...50F SOUTH OF KCHO.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
HIGH PRESSURE WILL BE SPRAWLED ACROSS THE OHIO VALLEY FRIDAY NIGHT
THROUGH SATURDAY NIGHT. UPPER LEVEL RIDGE OVER THE SOUTHEAST CONUS
WILL PROVIDE LITTLE STEERING FLOW...SO THE HIGH WILL MIGRATE VERY
SLOWLY EWD DURING THIS TIME. NAM SUGGESTS POSSIBLE UPSLOPE SLOW
SATURDAY AND SATURDAY NIGHT AS THE ORIENTATION OF THE HIGH MAY DRAW
IN SOME MOISTURE FROM THE LOWER GREAT LAKES. THIS IS NOT SUPPORTED
BY GFS...AND CAPPED POPS BELOW SCHC FOR NOW. COOL ADVECTION WILL
CONTINUE UNDER NW WINDS. SOME GUSTS UP TO 20KT POSSIBLE DURING THE
DAYLIGHT HOURS SATURDAY...MORESO ACROSS NRN MD. IN TERMS OF
TEMPS...NEAR NORMAL LOWS EXPECTED FRIDAY NIGHT...IN THE 20S ACROSS
MOST OF THE FORECAST AREA. HIGHS SATURDAY WILL BE IN THE MID-UPPER
40S...WITH SOME SPOTS POSSIBLY REACHING 50. LOWS IN THE UPPER 20S TO
LOW 30S SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL MOVE OVERHEAD SUNDAY AND REMAIN THERE THROUGH THE
DAY MONDAY. THIS WILL KEEP SKIES MOSTLY SUNNY AND TEMPS NEAR NORMAL
BOTH DAYS. SOUTHERN STREAM LOW PRESSURE WILL APPROACH THE AREA AS
THE HIGH SLIDES SOUTH AND CLOUDS WILL GRADUALLY INCREASE TUESDAY.
THE UPPER LEVEL SHORT WAVE THAT THE LOW IS RIDING ALONG WILL LIFT
RAPIDLY ALONG THE DOWNSTREAM SIDE OF A BROAD TROUGH...AND THE
SURFACE LOW WILL FOLLOW SUIT...LIFTING THROUGH THE GREAT LAKES. AS
IS THE CASE TYPICALLY WITH THESE QUICKLY LIFTING LOWS...THE SURFACE
COLD FRONT WILL WEAKEN RAPIDLY AND PROGRESS SLOWLY...RESULTING IN
VERY LITTLE RAINFALL SURVIVING THE JOURNEY ACROSS THE APPALACHIANS.
CHANCE POPS KEPT MAINLY WEST OF I-95 TUESDAY.
CHILLY NORTHWESTERLY FLOW WILL FILL IN AS THE DETERIORATING COLD
FRONT MOVES OFF THE COAST WEDNESDAY. LIGHT UPSLOPE SNOW SHOWERS ARE
POSSIBLE FOR THE POTOMAC HIGHLANDS DURING THIS TIME. TEMPS WILL DIP
A BIT BELOW NORMAL FOR WEDNESDAY AND THURSDAY WILL BE A CHILLY
DECEMBER DAY. PREVIOUS MODEL RUNS BROUGHT A UPPER LEVEL LOW THROUGH
THE AREA FOR THE END OF NEXT WORKWEEK...BUT THAT IS NO LONGER THE
CASE...SO HAVE CONTINUED TO LEAVE POPS OUT OF THE FORECAST
THURSDAY.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
MVFR CONDS POSSIBLE IN ANY REMAINING SNOW OVER DC METROS BEFORE
TAPERING OFF/SHIFTING EAST THROUGH THIS EVENING. WLY/NWLY GUSTS OF
20 TO 25 KT THIS EVENING...BRIEF LULL LATE TONIGHT...THEN NWLY GUSTS
25 KT AGAIN FRIDAY.
VFR CONDITIONS EXPECTED FRIDAY NIGHT THROUGH SATURDAY NIGHT. NW
WINDS AROUND 10KT SATURDAY...POSSIBLY GUSTING TO 15KT AT TIMES.
OVERNIGHT WINDS LESS THAN 10KT. VFR THEN INTO NEXT WEEK UNDER HIGH
PRESSURE.
&&
.MARINE...
SCA FOR ALL WATERS THROUGH FRIDAY EVENING AS STRONG PRESSURE
GRADIENT PERSISTS. NWLY FLOW WILL CONTINUE TO GUST AROUND 25 KT
THROUGH THIS TIME.
NWLY FLOW WILL CONTINUE FRIDAY NIGHT THROUGH SATURDAY NIGHT WITH THE
WATERS BETWEEN A MARITIME LOW AND HIGH PRESSURE OVER THE OHIO
VALLEY. WINDS ON THE BAY WILL REMAIN AT OR NEAR SMALL CRAFT
ADVISORY CRITERIA INTO SUNDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ530>534-
537-539>541-543.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
ANZ535-536-538-542.
&&
$$
SYNOPSIS...BAJ
NEAR TERM...BAJ
SHORT TERM...KS
LONG TERM...CEB
AVIATION...BAJ/KS/CEB
MARINE...BAJ/KS/CEB
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1231 PM CST Thu Dec 11 2014
.SHORT TERM...(Today and Tonight)
Issued at 236 AM CST THU DEC 11 2014
It is a cold and dreary morning across the Missouri Ozarks with
temperatures mainly in the middle 30s. The showers associated with
an exiting shortwave are still lingering mainly for areas along
and south of I-44 this morning. Have followed closely with the
Hi-Res short term models like the RUC and WRF with the evolution
of these scattered showers through 12z. Thinking is this will move
out of southern Missouri by 12z this morning. The remainder of the
area will continue to see patchy drizzle and light fog this morning.
Cloudy skies are here to stay for a while along with drizzle and
light fog from time to time through the end of the week.
Temperatures today will not budge much with highs only in the
lower to middle 40s expected today. Low clouds...areas of drizzle
and light fog can be expected once again this evening through
early Friday morning...especially for areas along and west of
Highway 65 and on top of the Ozark Plateau.
.LONG TERM...(Friday through Wednesday)
Issued at 236 AM CST THU DEC 11 2014
Friday will be a touch milder with highs in the lower 50s and
upper 50s to near 60 by Saturday. Like mentioned before...clouds
are here to stay through the weekend. The ground temperature will
be colder than the air temperature Friday night and again on
Saturday night with milder and moist air moving over that cold
ground. The SREF probabilities for fog development is higher for
those nights. There could be some localized dense fog potential
along with more drizzle. The forecast soundings show a completely
saturated air column from the ground up to 5k feet.
The potent storm system affecting the west coast of the country
the next day or so will be affecting our weather late Sunday into
Monday. A strong and vertically stacked low pressure system will
move across the south central Plains region Sunday night. This
will bring widespread rain and possibly isolated thunder to the
area late Sunday through Monday. No severe weather is expected
with this system. Average rainfall expected will be around an inch.
Showers or drizzle will lingering on the back side of the exiting
storm system Monday afternoon through Tuesday. Temperatures will
be knocked back down to more seasonable levels early and middle of
next week with a somewhat zonal flow expected in the upper levels.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1225 PM CST THU DEC 11 2014
High pressure east of the region will keep the region in MVFR
flight conditions as surface flow remains from the southeast.
Conditions at all area terminals will fall to IFR or occasionally
LIFR conditions with Ceilings and visibilities being impacted. The
06 to 16Z period will see the lowest flight categories with the
greatest impacts with 1/2 to 1/4SM Visibilities and Vertical
Visibilities as 100ft at all locations.
Limited improvements are expected through mid day Friday.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Hatch
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1236 PM CST THU DEC 11 2014
.SYNOPSIS...
ISSUED AT 350 AM CST THU DEC 11 2014
H5 ANALYSIS TONIGHT HAS AN AREA OF LOW PRESSURE CENTERED OVER NEW
YORK CITY WITH A TROUGH EXTENDING SWD INTO THE WESTERN ATLANTIC.
FURTHER WEST...A POSITIVELY TILTED RIDGE EXTENDED FROM THE FOUR
CORNERS INTO WESTERN ONTARIO. WEST OF THE RIDGE...A TROUGH OF LOW
PRESSURE EXTENDED FROM THE GULF OF ALASKA SWD INTO THE EASTERN
PACIFIC. CURRENT WV IMAGERY...HAS A DECENT PLUME OF MOISTURE
EXTENDING FROM CALIFORNIA...NWD INTO WESTERN MONTANA AND THE
PRAIRIE PROVINCES OF CANADA. A SECONDARY MOISTURE TAP EXTENDED
ACROSS MEXICO INTO THE GULF OF MEXICO AND THE GULF COAST STATES.
ACROSS SOUTH DAKOTA AND NEBRASKA...DRY AIR ALOFT WAS NOTED. AT
THE SURFACE...HIGH PRESSURE REMAINED ANCHORED ACROSS THE UPPER
MIDWEST...WHILE A WEAK SURFACE TROUGH EXTENDED FROM SERN MT INTO
EASTERN WYOMING AND NERN COLORADO. LIGHT SRLY WINDS WERE PRESENT
ACROSS THE PLAINS STATES WITH LOW LEVEL MOISTURE FLOWING NORTH
INTO CENTRAL AND EASTERN NEBRASKA TONIGHT. LOW LEVEL CLOUDS AND
DENSE FOG WERE PRESENT EAST OF A LINE FROM HAYES CENTER...TO
TRYON...TO BASSETT AND NAPER. VISBYS ACROSS PORTIONS OF CENTRAL
AND SOUTHWESTERN NEBRASKA HAVE DROPPED TO UNDER A HALF A MILE
OVERNIGHT AND A DENSE FOG ADVISORY WAS IN EFFECT FOR LOCATIONS
EAST AND SOUTH OF A LINE FROM HAYES CENTER...TO SUTHERLAND...TO
DUNNING AND TAYLOR. TEMPERATURES VARIED WIDELY TONIGHT WITH
READINGS AROUND 20 IN THE EASTERN PANHANDLE...TO THE MIDDLE 30S
IN THE NORTHEASTERN FORECAST AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST THU DEC 11 2014
IN THE SHORT TERM...FOG THIS MORNING AND TONIGHT...AND ITS
IMPACTS ON HIGHS TODAY AND LOWS TONIGHT WILL BE THE MAIN
FORECASTING CONCERNS. FOR THIS MORNING...LIGHT SRLY WINDS AND A
SERIOUS LACK OF MIXING...WILL LENGTHEN THE DURATION OF FOG THIS
MORNING. A GLANCE AT THE HRRR AND NAM 12 VISBY PRODUCTS...HAVE
THIS BURNING OFF DURING THE 16Z TO 18Z TIME FRAME. FOR LOCATIONS
GENERALLY ALONG AND WEST OF A LINE FROM CURTIS...TO NORTH
PLATTE...TO BASSETT...HIGHS ARE EXPECTED TO REACH THE 50S TO
AROUND 60 IN THE PANHANDLE. FURTHER EAST HOWEVER...STRATUS WILL
PERSIST INTO THE EARLY AFTERNOON HOURS...WHICH WILL HOLD TEMPS
BACK INTO THE 40S. FORTUNATELY...WITH THE VERY DRY AIR ALOFT AND
AN EXPECTED LACK OF HIGH LEVEL CLOUDINESS TODAY...THINKING HERE
IS THAT THE FOG/STRATUS SHOULD BURN OFF FROM WEST TO EAST TDY.
ALBEIT...LATER IN THE EAST...THUS THE COOLER TEMPS. FOR
TONIGHT...BL CONDITIONS WILL MOISTEN QUICKLY AFTER SUNSET AND
WITH INCREASED BL MOISTURE PUSHING NORTH INTO CENTRAL AND EASTERN
PORTIONS OF THE FORECAST AREA OVERNIGHT...FOG POTENTIAL IS VERY
HIGH ONCE AGAIN. THE LATEST NAM BL RH PROGS AND VISBY PRODUCT IS
INDICATING A HIGH POTENTIAL FOR FOG/STRATUS DEVELOPMENT EAST OF A
LINE FROM WAUNETA...TO MULLEN...TO SPRINGVIEW. WITH GOOD
CONFIDENCE AND LITTLE CHANGE IN THE SURFACE PATTERN...IE. SURFACE
HIGH TO THE EAST AND LIGHT SRLY WINDS...HAVE INSERTED AREAS OF
FOG TONIGHT ALONG AND EAST OF THE BEFORE MENTIONED LINE. IN
ADDITION...RAISED MIN TEMPS EAST OF THIS LINE...GIVEN THE
EXPECTED MOISTURE ADVECTION. WEST OF THE LINE...CLEAR
SKIES...WILL LEAD TO SEASONAL LOWS IN THE 20S IN THE PANHANDLE
AND NORTHWESTERN SANDHILLS. LIKE TONIGHT...ON THE WESTERN
PERIPHERY OF THE FOG FIELD...VISBYS MAY DROP DOWN TO A MILE OR
LESS AND A DENSE FOG ADVZY MAY BE NEEDED. WILL ADVISE THE
ONCOMING SHIFT OF THE POSSIBLE NEED FOR THIS WITH THE AFTERNOON
FCST PACKAGE. ONE FINAL NOTE WITH RESPECT TO DRIZZLE...LOOKED
CLOSELY AT FCST SOUNDINGS FOR TONIGHT...AND THE SATURATED LAYER
IS VERY SHALLOW AT AROUND 500 TO 700 FT THICK TONIGHT. COULDN/T
FIND ANY LIFT IN THIS MOIST LAYER...SO WILL LEAVE OUT A MENTION
OF DRIZZLE FOR THE TONIGHT PERIOD.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CST THU DEC 11 2014
MAIN CONCERN WILL BE THE EFFECTS OF INCREASING MOISTURE AHEAD OF
THE TROUGH FRIDAY INTO SATURDAY...THEN DETERMINING THE TRACK OF
THE LOW PRESSURE SYSTEM ACROSS THE SOUTHERN/CENTRAL PLAINS. ALSO
TIMING THE COOLER AIR SUNDAY INTO MONDAY BEHIND THE SYSTEM.
FRIDAY WILL SEE THE UPPER LEVEL LOW COME ON SHORE ACROSS THE PAC
COAST...MEANWHILE A RIDGE BUILDS ACROSS THE PLAINS. SURFACE HIGH
SETTLES OVER THE MISS RVR VALLEY. SOUTHERLY WINDS ON THE WEST
SIDE OF THE HIGH WILL TAP GULF MOISTURE AND BRING IT NORTHWARD.
THE RICH BL MOISTURE REMAINS...ALTHOUGH IT WILL STILL BE SHALLOW
FOR THE CWA ON FRIDAY. MORNING FOG WILL ERODE FROM THE
WEST...ALTHOUGH NOT EXPECTED A CLEARING DAY FOR ALL. THIS MAKES
FOR A TRICKY FORECAST AS CLOUDS WILL LIKELY LIMIT MIXING...AND
KEEP TEMPS DOWN. HIGHS IN THE 60S ACROSS THE WEST...WITH
50S...MAYBE SOME 40S IN THE EAST.
THE TROUGH WILL PUSH ACROSS THE DESERT SOUTHWEST SATURDAY. STILL
VERY WARM ALOFT...AND MORE MOISTURE ARRIVES WITH THE SOUTHERLY
WINDS. MOIST TRANSPORT VECTORS ARE FAVORABLE TO INCREASE THE
DEPTH OF THE BL MOISTURE. ALSO SEEING A LITTLE LIFT IN THE RICH
BL...AND WILL INCLUDE SOME DRIZZLE FRIDAY NIGHT INTO SATURDAY
MORNING. THE BLANKET OF CLOUDS WILL HELP TO KEEP TEMPS ABOVE
FREEZING...SO ONLY INCLUDE DZ IN THE FORECAST NOW. THE WARM
AIR/MOIST ADVECTION CONTINUES DURING THE DAY...AND EXPECT CLOUDS
TO REMAIN THROUGH THE DAY. THIS WILL LIMIT THE MIXING AND
FORECAST HIGHS ARE BELOW GUIDANCE...WHICH COULD STILL BE TOO WARM
PENDING HOW THE WAA OVERCOMES THE CLOUDS. ALSO BUFKIT SOUNDINGS
SUGGEST SOME BETTER /ALBEIT ONLY A LITTLE/ OMEGA AS THE DEPTH OF
THE MOISTURE LAYER INCREASE. COULD BE ENOUGH FOR A LITTLE HEAVIER
DRIZZLE AND WORDED THE FORECAST FOR LIGHT RAIN IN THE EAST.
BY SUNDAY THE SYSTEM WILL PUSH ACROSS TH ROCKIES AND LIFT ACROSS
THE PLAINS. STILL SOME TIMING/TRACK ISSUES...WITH THE LATEST
ROUND OF MODELS ALL TAKING THE TRACK A LITTLE FURTHER SOUTH FROM
EARLIER RUNS. STILL HAVE ENOUGH LL MOISTURE IN PLACE WHICH WILL
BE AIDED BY SOME WRAP AROUND MOISTURE/LIFT WHICH SHOULD PRODUCE
SOME LIGHT PRECIP. ALSO GOING TO SEE TEMPS FALLING AS COOLER AIR
GETS DRAW INTO THE SYSTEM. BEST LIFT IS ALONG THE SOUTHERN BORDER
AND TO THE SOUTH AND EAST...WHICH BRINGS CONCERN TO AMOUNT OF QPF
FOR THE CWA. IT LOOKS BETTER FOR AT LEAST SOME LIGHT
PRECIP...ALTHOUGH ONLY A SLIGHT SHIFT NORTHWARD COULD PLACE SOME
MORE SIGNIFICANT QPF FOR THE CWA. ALL IN ALL...STILL NOT VERY
CONFIDENT ON AMOUNT OF QPF FOR THE CWA. ALSO MODELS SLOWED THE
COLD AIR PUSH WHICH LESSENS CONFIDENCE ON TIMING THE CHANGE OVER
FROM RAIN TO SNOW SUNDAY INTO MONDAY.
LINGERING WRAP AROUND SNOW MONDAY NIGHT ACROSS N CENTRAL...THEN
WEAK RIDGING WILL HELP TO REDUCE CLOUDS FOR MID WEEK. THE ACTIVE
PATTERN CONTINUES WITH ANOTHER TROUGH DIGGING INTO THE DESERT
SOUTHWEST BY WEDNESDAY. EYES WILL BEGIN TO MONITOR THIS AS IT
CROSSES THE SOUTHERN/CENTRAL PLAINS TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1226 PM CST THU DEC 11 2014
LOW CEILINGS/STRATUS CONTINUE TO ERODE FROM THE WEST...AND THE
WESTERN EXTENT OF THE CEILINGS CURRENTLY EXTENDS FROM KONL TO KBBW
TO NEAR KMCK. EXPECT BRIEF CLEARING THIS AFTERNOON ACROSS CENTRAL
NEBRASKA...THEN THE STRATUS WILL REDEVELOP OR MOVE BACK WEST
THROUGH CENTRAL INTO SOUTHWEST AND PORTIONS OF NORTH CENTRAL
NEBRASKA TONIGHT. LOW LEVEL MOISTURE WILL SLOWLY INCREASE THROUGH
TONIGHT...SO AREAS OF DENSE FOG LIKELY TO ACCOMPANY THE LOW
CEILINGS/STRATUS. THIS INCREASE IN MOISTURE MIGHT MAKE IT RATHER
DIFFICULT TO BURN OFF OR ERODE THE STRATUS ON FRIDAY...AND NOT
CONFIDENT THAT THE LOWER CEILINGS/STRATUS WILL CLEAR MUCH.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...MASEK
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1223 PM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 942 AM CST THU DEC 11 2014
THE FOG IS SLOW TO LIFT ACROSS OUR WEST WHERE A DENSE FOG ADVISORY
REMAINS IN EFFECT. HAVE ELECTED TO EXTEND THE DENSE FOG ADVISORY
THROUGH NOON GIVEN CONTINUING REPORTS OF ONE QUARTER MILE OR LESS
VISIBILITY OVER PORTIONS OF THE ADVISORY AREA. FOG COULD LINGER
INTO THE EARLY AFTERNOON HOURS...ALTHOUGH IT LIKELY WILL NO LONGER
BE DENSE BY AFTERNOON.
THE 09Z SREF IS INDICATING NEARLY A 100 PERCENT CHANCE OF
VISIBILITY REDUCTIONS TO LESS THAN 1 MILE ACROSS MUCH OF OUR AREA
AGAIN LATER THIS EVENING INTO TONIGHT. IT IS BECOMING MORE LIKELY
THAT WE WILL SEE AN EVEN MORE WIDESPREAD AREA OF DENSE FOG THIS
EVENING INTO TONIGHT WITH VISIBILITY RANGING FROM NEAR ZERO TO ONE
QUARTER OF A MILE. A NEW DENSE FOG ADVISORY MAY EVENTUALLY BE
WARRANTED FOR LATER THIS EVENING/TONIGHT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST THU DEC 11 2014
ALOFT: THE FLOW IS COMPLEX BUT ESSENTIALLY A RIDGE AXIS EXTENDED
FROM THE DESERT SW UP INTO THE CANADIAN PRAIRIES. THIS RIDGE WILL
SLOWLY CREEP TO THE E THRU TONIGHT WHILE REMAINING JUST W OF THE
FCST AREA. BY SUNRISE FRI...A POTENT SHORTWAVE TROF WILL BE MOVING
ONSHORE INTO SRN CA. THIS WILL BE PROVIDE THE BEST CHANCE FOR
MEANINGFUL PRECIP WE HAVE SEEN HERE SINCE LATE OCT. SEE BELOW FOR
THE DETAILS.
SURFACE: HIGH PRES WAS OVER THE UPPER MS VALLEY. IT WILL REMAIN
OVER THE MS VALLEY BUT GRADUALLY SINK S THRU TONIGHT.
NOW THRU SUNRISE: CLOUDY WITH SLOWLY DECREASING VSBYS...
ESPECIALLY ALONG AND W OF HWY 283. TEMPS HOLD STEADY IN THE LOW-
MID 30S.
FOG: BELIEVE VERIFYING THE FOG ADVISORY COULD BE SHAKY IN SOME
PLACES. DENSE FOG IS MOST LIKELY WITHIN 50 MILES ON EITHER SIDE OF
THE STRATUS EDGE. AREAS E OF HWY 183 ARE PROBABLY TOO FAR INTO THE
STRATUS AND BELIEVE VSBYS SHOULD BE NO WORSE THAN MVFR /3-5 MI/.
SO THE ERN ROW OF COUNTIES WAS TRIMMED OFF THE ADVISORY FROM
BUFFALO DOWN TO OSBORNE. THE ONLY COUNTIES I AM CONFIDENT IN
LEAVING DENSE FOG ARE DAWSON/GOSPER/FURNAS. PHELPS/HARLAN/
PHILLIPS/ROOKS ARE LOW CONFIDENCE. DID EXTEND THE ADVISORY THRU 10
AM AS IT IS VERY DIFFICULT TO GET RID OF FOG/DENSE FOG BEFORE LATE
AM THIS TIME OF YEAR.
TODAY: CLOUDY TO START WITH AREAS OF FOG W OF HWY 183 THRU
MIDDAY. EXPECT SOME SLOW IMPROVEMENT AND IT SHOULD BEGIN FROM THE
W WHERE THE STRATUS IS SHALLOWER. I HAVE THE ENTIRE FCST AREA
EVENTUALLY TURNING P/CLOUDY THIS AFTERNOON AND THIS COULD BE
OVERLY OPTIMISTIC...ESPECIALLY FOR PARTS OF THE AREA E OF HWY 281
WHERE THE STRATUS COULD LINGER THE ENTIRE DAY.
DESPITE THE WARM LOOK ALOFT...A SHALLOW COOL AIR MASS WAS IN
PLACE.
850 MB TEMPS WERE VERY WARM. IF NOT FOR THE SHALLOW COOL AIR MASS
AND STRATUS...TEMPS WOULD BE IN THE 60S TODAY. THE LOW-LVLS ARE
HIGHLY INVERTED /WARMER AIR ALOFT AND COLDER NEAR THE SFC/.
USED THE NAM LOW CLOUD PRODUCT FOR THE BASIS OF THE FCST WHICH
SUPPORTS FCSTR PATTERN RECOGNITION. HRRR LOW CLOUD PRODUCT IS ALSO
SUPPORTIVE.
HIGH TEMPS ARE LOW CONFIDENCE W OF HWY 183. WHILE MIXING WILL
INITIALLY BE SUPPRESSED...THE WRN EDGE OF THE STRATUS/FOG WILL BE
ERODED AND EXPECT THAT CLOUDS WILL BREAK-UP AND DECREASE FROM THE
W. AREAS W OF HWY 183 STAND THE BEST CHANCE FOR THE GREATEST
AMOUNT OF SUN TODAY. WHERE CLEARING OCCURS WILL PLAY A SUBSTANTIAL
ROLE IN HOW WARM TEMPS GET. WHILE IT`S NOT IN THE FCST...LOW 50S
WOULD BE POSSIBLE.
TONIGHT: ANY AREAS THAT ARE P/CLOUDY OR M/CLEAR WILL CLOUD BACK
OVER. HARD TO GET A HANDLE ON FOG POTENTIAL BECAUSE IT WILL HINGE
ON WHAT IS LEFT OF THE STRATUS AT SUNSET. FOR NOW PLAYED IT
SIMILAR TO THE PREVIOUS FCST WITH FOG DEVELOPING EARLY EVENING AND
EXPANDING. DRZL WAS WITHDRAWN FROM THE FCST AS MOISTURE JUST DOES
NOT APPEAR DEEP ENOUGH IN CROSS SECTIONS/SOUNDINGS.
LOW TEMPS WILL PROBABLY OCCUR WELL BEFORE MIDNIGHT...BEFORE FOG/
STRATUS OVERTAKE THE FCST AREA. ONCE THAT OCCURS...TEMPS SHOULD
FLAT-LINE OR EVEN SLOWLY CLIMB.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 504 AM CST THU DEC 11 2014
FOR FRIDAY THROUGH SATURDAY NIGHT...THE EXPECTED DRIZZLE AND FOG
IS STILL ON...ONLY I HIT THE DRIZZLE A LITTLE HARDER IN WORDING AS
SIGNALS ARE QUITE STRONG...ESPECIALLY ON SATURDAY. FOR
TEMPERATURES...I DID BUMP LOWS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT WITH THE EXTENSIVE STRATUS EXPECTED. SATURDAY NIGHT COULD BE
QUITE WARM WITH SOME LOCATIONS IN THE CENTRAL AND SOUTHEAST NOT
DROPPING BELOW THE LOWER 50S.
FOR THE BIG SHOW...THE EXPECTED TROUGH WILL MOVE OUT OF THE
ROCKIES ON SUNDAY. TIMING AMONG NUMERICAL MODELS IS INITIALLY
SIMILAR AS THE WAVE MOVES OUT OF THE ROCKIES AND CONTINUED WARM
AIR EXISTS FOR OUR AREA AHEAD OF THE TROUGH AND THE SUBSEQUENT
DEVELOPING ASSOCIATED LOW. ALTHOUGH THERE ARE SOME FAIRLY MINOR
TRACK DIFFERENCES THROUGH THE SOUTHERN PLAINS...THE REAL POTENTIAL
FOR A BUST WILL BE HOW QUICKLY THE TROUGH AXIS MAKES ITS WAY EAST.
THE ECMWF CONTINUES TO LAG A BIT COMPARED TO OTHER NUMERICAL
MODELS AND FRANKLY...I BUY THAT. IN YEARS PAST...SIMILAR
SITUATIONS HAVE OCCURRED AND THE SLOWER SOLUTION SEEMS TO OFTEN
TIMES BE THE WAY TO GO...ESPECIALLY CONSIDERING THAT ITS THE OFT
MORE RELIABLE ECMWF FOR THE EXTENDED IN THIS CASE. THIS LEADS ME
TO BELIEVE THAT THE COLDER AIR WILL BE SLOWER TO MOVE IN AND I
HAVE BUMPED UP HIGHS A TAD ON MONDAY FROM THE PREVIOUS
FORECAST...WHICH COULD CUT INTO OUR SNOW POTENTIAL AS COLD AIR
MIGHT NOT MAKE IT HERE IN TIME TO PRODUCE AS MUCH SNOW.
HOWEVER...EVEN THE SLOWER ECMWF INDICATES THAT OUR FAR WEST/NORTH
COULD BE IN FOR SOME SNOW AS EARLY AS SUNDAY NIGHT AND CONTINUING
INTO MONDAY...ALTHOUGH THE FARTHER NORTHWEST ONE GOES...THE LESS
POTENTIAL QPF THERE WILL BE. WE ARE STILL FAR ENOUGH OUT THAT
THERE IS INCREDIBLE UNCERTAINTY HERE. I LEFT MUCH OF THE
SUPERBLEND INITIALIZED GRIDS FOR MONDAY NIGHT AND BEYOND IN TACT.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1212 PM CST THU DEC 11 2014
THE MAIN AVIATION CONCERN WILL CONTINUE TO CENTER AROUND BOTH LOW
VISIBILITY AND LOW CEILINGS ESPECIALLY THIS EVENING THROUGH FRIDAY
MORNING. AT THIS POINT IT IS LIKELY THAT KEAR AND KGRI WILL
EXPERIENCE IFR OR WORSE CONDITIONS THROUGH AT LEAST FRIDAY MORNING
AND POSSIBLY LONGER. THE VISIBILITY AND CEILINGS WILL QUICKLY COME
DOWN THIS EVENING AND EXPECT EVEN LIFR CONDITIONS COULD OVERTAKE
OUR AREA AIRPORTS FOR MUCH OF THE OVERNIGHT PERIOD INTO MID
MORNING ON FRIDAY. A DENSE FOG ADVISORY IS BECOMING MORE LIKELY
FOR LATE THIS EVENING INTO FRIDAY MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...WESELY
SHORT TERM...HALBLAUB
LONG TERM...HEINLEIN
AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS BISMARCK ND
443 PM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 442 PM CST THU DEC 11 2014
GIVEN CURRENT VISIBILITIES OF AROUND ONE HALF TO ONE QUARTER OF A
MILE FROM CARRINGTON THROUGH JAMESTOWN...ASHLEY AND
ELLENDALE...AND THE 21 UTC HRRR VISIBILITY FORECAST WHICH KEEPS
DENSE FOG THROUGH THE NIGHT...ISSUED A DENSE FOG ADVISORY FOR THE
AFOREMENTIONED AREAS. ROADS WILL BECOME SLIPPERY AS FOG DROPLETS
FREEZE ON ROADWAYS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 311 PM CST THU DEC 11 2014
THE MAIN FORECAST ISSUE CONTINUES TO BE TEMPERATURES AND CLOUDS.
LARGE DIFFERENCES REMAIN BETWEEN THE VERY MILD SOUTHWEST AND THE
COOL EAST.
CURRENTLY...SOUTHERLY FLOW CONTINUES ACROSS WESTERN AND CENTRAL
NORTH DAKOTA BETWEEN A SURFACE HIGH FROM THE WESTERN GREAT LAKES
INTO THE SOUTHERN PLAINS...AND LOW PRESSURE OVER THE NORTHERN AND
CENTRAL HIGH PLAINS. WEAK SURFACE TROUGH OVER EASTERN MONTANA INTO
WESTERN MONTANA WITH TEMPERATURES INTO THE 50S. A LIGHT SOUTH TO
SOUTHEAST FLOW TO THE EAST OF TROUGH IS SLOWING OUR WARM-UP. BUT
EVEN WITH THE SLOW WARM-UP AND THE STRATUS IN THE FAR SOUTH
CENTRAL AND JAMES RIVER VALLEY...WE ARE STILL AHEAD OF OUR 2 PM
TEMPERATURES ON WEDNESDAY. THUS NOT A BAD DAY OVERALL.
WILL KEEP A MENTION OF FOG AND CLOUDS OVER THE SOUTHEAST CWA
TONIGHT. SHOULD BE ANOTHER MILD NIGHT...EVEN A LITTLE WARMER THAN
LAST NIGHT MOST AREAS...WITH LOWS IN THE MID TO UPPER 20S.
AS THE UPPER LEVEL RIDGE OVER THE AREA MOVES A LITTLE FARTHER
EASTWARD BY FRIDAY...OUR SOUTHERLY SURFACE GRADIENT SHOULD ALSO
SHIFT EAST...ALLOWING FOR BETTER DAYTIME MIXING...AND REALIZING
OUR FORECAST HIGHS. STILL OPTIMISTIC WITH UPPER 50S AND MAYBE SOME
60S SOUTHWEST...WITH HOPEFULLY SOME LOWER 40S FROM THE TURTLE
MOUNTAINS INTO THE JAMES RIVER VALLEY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 311 PM CST THU DEC 11 2014
ONE MORE MILD DAY SATURDAY BEFORE SPLIT FLOW ALOFT DEVELOPS. THIS
LEAVES THE NORTHERN PLAINS LARGELY IMPACTED BY THE NORTHERN
STREAM SEGMENT INTO EARLY NEXT WEEK ALLOWING CAA INTO THE DAKOTAS
AND VERY LIMITED PRECIPITATION SATURDAY NIGHT AND SUNDAY WITH
JUST SPOTTY SLIGHT CHANCES OF SNOW.
MAINLY DRY CONDITIONS AND SEASONAL TEMPERATURES AFTERWARDS MONDAY-
THURSDAY WITH A VERY DISORGANIZED UPPER LEVEL PATTERN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 442 PM CST THU DEC 11 2014
LIFR CONDITIONS IN FREEZING FOG WILL CONTINUE AT KJMS THROUGH AT
LEAST 12-14 UTC FRIDAY MORNING. OTHERWISE VFR CONDITIONS AT THE
REMAINING TAF SITES WITH ONLY HIGH CLOUDS AND A SOUTHERLY SURFACE
FLOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 6 AM CST FRIDAY FOR NDZ025-037-047-048-
050-051.
&&
$$
UPDATE...AYD
SHORT TERM...TWH
LONG TERM...NH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1232 PM CST THU DEC 11 2014
.UPDATE...
ISSUED AT 1225 PM CST THU DEC 11 2014
CONTINUED WITH MINOR TEMPERATURE TWEAKS OTHERWISE NO CHANGES.
UPDATE ISSUED AT 936 AM CST THU DEC 11 2014
EXTENDED FOG MENTION INTO LATE MORNING AND RAISED MAXIMUM
TEMPERATURES IN THE VALLEY A DEGREE OR SO. NO OTHER CHANGES.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST THU DEC 11 2014
CLOUDS...CLOUDS...CLOUDS! SATELLITE IMAGERY INDICATES LOW-LEVEL
CLOUDS ARE RETURNING FROM THE SOUTHERN SOURCE REGION AND HAVE
OVERTAKEN ALL BUT THE FAR NORTHWEST FA. LOW-LEVEL FLOW DOES NOT
DEVIATE MUCH UNTIL A SFC TROUGH/COLD FRONT IN THE LONG TERM
PERIOD. SOME GUIDANCE INDICATES 925MB RH LOWERING DURING THE
DAYTIME HOURS...BUT 950MB RH REMAINING HIGH. THERE MAY BE SOME
BREAKS IN THE CLOUDS DURING THE DAYTIME HOURS...BUT MOSTLY CLOUDY
CONDITIONS SHOULD PREVAIL. RAP CIG GUIDANCE INDICATES CLOUDS WILL
HOLD TOUGH. OBVIOUSLY...KEEPING LOW CLOUDS IN PLACE WILL HAMPER
TEMPERATURES. THE LONG ADVERTISED WARM-UP LOOKS GOOD AT 4000-5000
FEET ABOVE THE SURFACE...BUT NOT WHERE MOST PEOPLE ACTUALLY LIVE.
THUS...SIGNIFICANTLY LOWERED MAX TEMPS. FOG ALSO
POSSIBLE...ALTHOUGH DO NOT ANTICIPATE DENSE FOG AS SFC WINDS
REMAIN AT LEAST 10 KNOTS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 402 AM CST THU DEC 11 2014
FRIDAY NIGHT-SATURDAY NIGHT...SURFACE TROUGH APPROACHES AND MOVES
THROUGH THE REGION. THIS WILL INCREASE LOW LEVEL MOISTURE EVEN
FURTHER (SFC DEWPOINTS INTO THE MID-UPPER 30S...POSSIBLY 40F). LOW
CLOUDS LIKELY WILL REMAIN...WITH DRIZZLE BECOMING POSSIBLE WITH
WEAK LOW LEVEL LIFT AHEAD OF THE SFC TROUGH. AGAIN...LOWERED MAX
TEMP FOR SATURDAY CONSIDERING EXPECTED LOW CLOUDS...ALTHOUGH NOT AS
MUCH AS PREVIOUS DAYS CONSIDERING THE HIGHER DEWPOINT VALUES.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH REMAINS OVER THE EASTERN
PACIFIC WHILE THE LONG WAVE RIDGE WAS OVER THE NORTHERN PLAINS.
PATTERN DE AMPLIFIES A BIT. LONG WAVE RIDGE RE DEVELOPS OVER THE
ROCKIES AND SHIFTS INTO THE HIGH PLAINS BY THE END OF THE PERIOD.
THE GFS WAS FASTER THAN THE ECMWF THROUGH THE PERIOD. BOTH GFS AND
ECMWF WERE TRENDING SLIGHTLY SLOWER OVER THE LAST COUPLE MODEL
RUNS. WILL PREFER THE ECMWF.
TROUGH OVER THE EASTERN PACIFIC WILL MOVE ACROSS SOUTHERN CANADA BY
SUN/MON AND BRING COOLER AIR T THE AREA.
LITTLE CHANGE TO TEMPS. A DEGREE OR SO HIGHER FOR SUN AND MON AND A
DEGREE LOWER FOR TUE. NO CHANGE FOR WED COMPARED TO YESTERDAYS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1225 PM CST THU DEC 11 2014
IFR CIGS EXPECTED TO CONTINUE THE NEXT 24HRS AT ALL TERMINALS WITH
THE EXCEPTION OF DVL WHICH IS ON THE EDGE OF THE STRATUS DECK AND IS
EXPECTED TO SCATTER OUT THIS AFTERNOON AND THEN BECOME OVC AGAIN
THIS EVENING. SOUTH WINDS WILL PREVAIL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...AV
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...AV
AREA FORECAST DISCUSSION
NWS PORTLAND OR
251 PM PST THU DEC 11 2014
.SYNOPSIS...A DEEP LOW PRESSURE SYSTEM JUST WEST OF CANNON BEACH
OREGON WILL MOVE NORTHWARD JUST OFF THE OREGON AND WASHINGTON COAST
LATE THIS AFTERNOON AND EVENING PRODUCING VERY STRONG...POTENTIALLY
DAMAGING WIND FROM THE COAST TO THE CASCADE FOOTHILLS. SLIGHTLY
COOLER WITH ISOLATED TO SCATTERED SHOWERS TONIGHT AND FRIDAY AS AN
UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NORTHWEST. AN UPPER LEVEL
RIDGE WILL BRING A PERIOD OF DRY WEATHER THIS WEEKEND. EASTERLY WINDS
WILL DEVELOP SUNDAY AND HELP COOL TEMPERATURES CLOSER TO SEASONAL
NORMALS. A PROGRESSIVE WEATHER PATTERN RETURNS NEXT WEEK.
&&
.SHORT TERM...TONIGHT THROUGH SUNDAY...THE OFFSHORE
BUOY...46089...WHICH IS AROUND 80 MILES WEST OF CANNON BEACH REPORTED
A SEA LEVEL PRESSURE OF 974 MB THIS AFTERNOON. SATELLITE IMAGERY
SHOWED THE CENTER OF A LOW NEAR THE BUOY AT THIS TIME AND SUSPECT
THAT THE CENTER OF THE LOW HAD THE SAME PRESSURE. THIS LOW IS
RESULTING IN SHARP SURFACE PRESSURE GRADIENTS ACROSS OREGON PRODUCING
VERY STRONG WINDS.
AS OF 130 PM THIS AFTERNOON...WE HAVE RECEIVED SEVERAL REPORTS OF
FLYING DEBRIS AND MINOR PROPERTY DAMAGE FOR AREAS SOUTH OF LINCOLN
CITY AND SALEM...WEST OF THE CASCADE FOOTHILLS. HAVE ALSO SEEN SOME
IMPRESSIVE WIND GUSTS AT SOME OF THE COASTAL AND HIGHER ELEVATION
SITES. CHECK OUT PDXLSRPQR AND PDXPNSPQR FOR A SUMMARY OF THESE
REPORTS THROUGHOUT THE EVENT...OR FOLLOW US ON FACEBOOK AND TWITTER.
SO FAR THE FORECAST IS ON TRACK AND EXPECT THESE GUSTY WINDS TO TRACK
NORTHWARD THROUGH THE AFTERNOON...REACHING THE PORTLAND METRO AREA
AROUND 3 PM...POSSIBLY BEFORE WE DELIVER THIS DISCUSSION...AND ACROSS
SW WASHINGTON AROUND 4 PM. THE WINDS WILL WEAKEN CONSIDERABLY BEHIND
THE LOW THIS EVENING TO THE SOUTH AND TONIGHT NORTH OF SALEM.
HAVE BACKED OFF ON SHOWERS QUITE A BIT FOR THIS AFTERNOON AND
EVENING...AND EVEN MORE SO FOR TONIGHT. THE THUNDERSTORMS HAVE
REMAINED WELL OFFSHORE FOR THE MOST PART...BUT AREAS OVER SOUTHERN
OREGON HAVE SEEN SOME THUNDERSTORMS IN THE WAKE OF THE LOW AND HAVE
CONTINUED ISOLATED THUNDERSTORMS FOR THE WATERS THROUGH TONIGHT.
THERE IS A GREATER CHANCE FOR SHOWERS FRIDAY...ESPECIALLY OVER THE
HIGHER TERRAIN AS AN UPPER LEVEL TROUGH APPROACHES THE AREA. ANOTHER
SURFACE LOW MOVING SOUTH OF THE AREA WILL CONTRIBUTE TO ENHANCED
SHOWERS FOR LANE COUNTY. ONSHORE FLOW IN THE AFTERNOON COMBINED WITH
COOLING ALOFT WILL RESULT IN COOLER AFTERNOON TEMPERATURES FRIDAY.
THE TEMPERATURES WILL STILL BE ABOVE NORMAL PROVIDING AND EXPECT A
SLIGHT CHANCE OF THUNDERSTORMS AS THE UPPER TROUGH AXIS MOVES INLAND
FRIDAY AFTERNOON AND EVENING.
AN UPPER RIDGE WILL MOVE IN BEHIND THE TROUGH FRIDAY NIGHT AND
SATURDAY MORNING PUTTING AN END TO THE RAIN. SKIES SHOULD CLEAR AND
RADIATION FOG IS LIKELY IN THE INTERIOR VALLEYS. SURFACE HIGH
PRESSURE EAST OF THE CASCADES WILL STRENGTHEN LATE SATURDAY NIGHT AS
ANOTHER LOW MOVES ACROSS THE NE PACIFIC AND EAST WINDS WILL DEVELOP
ACROSS THE REGION BY SUNDAY MORNING.
THESE OFFSHORE WINDS SHOULD PROMOTE MORE CLEARING...DRIER WEATHER AND
COOLER TEMPERATURES SUNDAY. THE TROUTDALE TO DALLES EASTERLY GRADIENT
IS CURRENTLY FORECAST TO BE AROUND 7 MB BY SUNDAY AFTERNOON WHICH
WOULD RESULT IN EASTERLY WIND GUSTS AROUND 35 TO 40 KT THROUGH THE
GORGE. THIS WILL PROMOTE FURTHER COOLING FOR THE REGION AND
TEMPERATURES WILL BE CLOSER TO THE SEASONAL NORMALS...WITH HIGHS IN
THE MID TO UPPER 40S AND LOWS IN THE 30S. TJ
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...GUSTY EAST WINDS WILL
CONTINUE NEAR THE GORGE THROUGH EARLY MONDAY AS THE UPPER LEVEL
RIDGE SLOWLY SLIDES TO THE EAST. THE NEXT FRONTAL SYSTEM LOOKS TO
ARRIVE ON MONDAY AND BRING ANOTHER ROUND OF RAIN TO THE REGION. THE
PROGRESSIVE WEATHER PATTERN WILL CONTINUE THROUGH THE WEEK. A WEAK
SHORTWAVE LOOKS TO MOVE THROUGH THE REGION ON TUESDAY AND WILL KEEP
SHOWERY CONDITIONS INTO WEDNESDAY. A MUCH STRONGER FRONT LOOKS TO
ARRIVE ON OUR DOORSTEPS ON LATE WEDNESDAY INTO EARLY THURSDAY.
TEMPERATURES THROUGHOUT THE EXTENDED WILL GENERALLY BE NEAR SEASONAL
NORMALS. /64
&&
.AVIATION...A STRONG LOW PRESSURE SYSTEM WILL BRING WINDY CONDITION
THROUGH THIS EVENING WITH VFR VIS AND CIGS AT ALL TAF SITES. STRONG
SOUTH WINDS WITH GUSTS OF 50 KT AT THE COAST AND 45 KT INLAND WILL
CONTINUE THROUGH AROUND 03Z FRIDAY. STRONGEST WINDS ARE EXPECTED
BETWEEN 00Z AND 02Z FRIDAY. VFR CONDITIONS WILL LIKELY PERSIST INTO
FRIDAY AFTERNOON AT MOST TAF SITES. HOWEVER...AS THE WINDS WEAKEN
AND THE SKIES CLEAR WE COULD SEE THE DEVELOPMENT OF FOG AND LOW
LEVEL STRATUS IN THE CENTRAL AND SOUTHERN WILLAMETTE VALLEY AFTER
12Z...BUT CONFIDENCE IS STILL LOW AT THE MOMENT.
KPDX AND APPROACHES...VFR CONDITIONS EXPECTED TO CONTINUE THROUGH
FRIDAY AFTERNOON. STRONG SOUTHERLY WINDS WITH GUSTS TO 45 KT ARE
POSSIBLE THROUGH AROUND 03Z FRIDAY. THERE IS A SLIGHT CHANCE THAT
MVFR CONDITIONS MAY DEVELOP AFTER 12Z FRIDAY. /64
&&
.MARINE...OFFSHORE LOW CONTINUES MOVING NORTH WITH THE APPROXIMATE
CENTER ABOUT 60 NM OFF OF LINCOLN CITY AT 130 PM. BUOY 89
REPORTING A CURRENT PRESSURE OF 975 MB WITH THE LOW CENTER STILL
ON THE WAY. LOOKS LIKE MODELS FROM YESTERDAY MAY HAVE HANDLED THE
MINIMUM PRESSURE A BIT BETTER. REGARDLESS...FEELING LIKE THE
FORECAST IS WELL ON TRACK WITH A 1030 AM ASCAT SATELLITE PASS
SHOWING 50 KT SUSTAINED WINDS OFF THE PORT ORFORD COAST AND THOSE
TEND TO RUN TOO LOW AT THE HIGHER SPEEDS. GENERALLY EXPECT STORM
FORCE WINDS TO REACH TILLAMOOK AROUND 2 PM WITH HURRICANE FORCE
WIND GUSTS SHORTLY THEREAFTER. LATEST HIGH RESOLUTION HRRR MODEL
HAS A GOOD HANDLE ON THE LOW...ALTHOUGH STILL A BIT WEAK ON THE
STRENGTH. STILL SHOWING A BROAD SWATH OF HURRICANE FORCE
GUSTS...65 KT AND LOCALLY 70 KT...FROM THE CENTRAL INNER WATERS
AND IN A V PATTERN TO THE NORTH FOR THE NEXT FEW HOURS AT LEAST.
THESE EXTREME WIND GUSTS SHOULD REMAIN SOUTH OF THE COLUMBIA
RIVER BUT WITH SOLID GUSTS 45 TO 55 OR 60 KT NORTH OF THE
COLUMBIA. AS THE LOW PUSHES NORTH THROUGH THE EVENING...WILL SEE
WINDS SHIFT WESTERLY AND DRAMATICALLY DROP OF OVER THE FOLLOWING 6
TO 10 HOURS. IN FACT...MOST WINDS WILL LIKELY BE 15 KT OR LESS BY
10 AM FRIDAY.
SEAS HAVE INDEED RESPONDED AS EXPECTED. BUOY 15 OFF PORT ORFORD
HAS RISEN TO 31 FEET/11 SECONDS AND LARGELY STABILIZED THERE AT
1PM WITH BUOY 50 HAVING ECLIPSED 22 FEET/11 SECONDS. EXPECT THIS
TREND TO CONTINUE AS THE WINDS INCREASE THE LOW PUSHES NORTH.
GIVEN THE FAST MOVEMENT OF THE SYSTEM...SEAS ARE PRIMARILY WIND
WAVE/FRESH SWELL DRIVEN AND SHOULD SUBSIDE ALMOST AS QUICKLY.
FEEL SEAS WILL BE BACK INTO THE HIGH TEENS ALL AREAS NO LATER THAN
DAYBREAK AND TO THE LOW TEENS BY NOON.
BRIEF HIGH PRESSURE BUILDS FOR FRIDAY AND SATURDAY BEFORE ANOTHER
LOW DEEPENS WELL OFFSHORE. EXPECT OFFSHORE WINDS HEADING INTO
EARLY NEXT WEEK WITH EASTERLY SMALL CRAFT ADVISORY WINDS PROBABLE
BEGINNING EARLY SUNDAY MORNING. SEAS INCREASE TO AROUND 15 FEET
FROM LONG PERIOD WESTERLY SWELL MONDAY AND TUESDAY. /JBONK
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING FOR CASCADE
FOOTHILLS IN LANE COUNTY-CENTRAL COAST RANGE OF WESTERN
OREGON-CENTRAL OREGON COAST-CENTRAL WILLAMETTE VALLEY-
NORTHERN OREGON CASCADE FOOTHILLS-SOUTH WILLAMETTE VALLEY.
HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR GREATER
PORTLAND METRO AREA-LOWER COLUMBIA.
HIGH SURF ADVISORY UNTIL 10 PM PST THIS EVENING FOR CENTRAL
OREGON COAST-NORTH OREGON COAST.
HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR COAST RANGE
OF NORTHWEST OREGON-NORTH OREGON COAST.
WA...HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR GREATER
VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY-SOUTH
WASHINGTON CASCADE FOOTHILLS.
HIGH SURF ADVISORY UNTIL 10 PM PST THIS EVENING FOR SOUTH
WASHINGTON COAST.
HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR SOUTH
WASHINGTON COAST-WILLAPA HILLS.
PZ...HURRICANE FORCE WIND WARNING UNTIL 7 PM PST THIS EVENING FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL NOON
PST FRIDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1002 AM PST THU DEC 11 2014
.SYNOPSIS...A DEEP LOW PRESSURE SYSTEM JUST WEST OF FLORENCE OREGON
WILL MOVE NORTHWARD JUST OFF THE OREGON AND WASHINGTON COAST TODAY
PRODUCING VERY STRONG...POTENTIALLY DAMAGING WIND FROM THE COAST TO
THE CASCADE FOOTHILLS. COOLER AND SHOWERY WEATHER EXPECTED TONIGHT
AND FRIDAY. AN UPPER LEVEL RIDGE WILL BRING A PERIOD OF DRY WEATHER
THIS WEEKEND BEFORE A PROGRESSIVE WEATHER PATTERN RETURNS EARLY NEXT
WEEK.
&&
.UPDATE...SATELLITE IMAGERY SHOWS A TIGHTLY WOUND LOW PRESSURE AROUND
160 MILES WEST OF FLORENCE OREGON. SHIP REPORTS AND BUOY OBSERVATIONS
NEAR THE LOW CENTER A COUPLE OF HOURS WHEN IT WAS SLIGHTLY FURTHER
SOUTH SUGGESTS THAT THE MEAN SEA LEVEL PRESSURE IS AROUND 978 MB.
THIS IS VERY CLOSE TO WHAT THE WEATHER MODELS WERE FORECASTING.
HISTORICALLY...NW OREGON AND SW WASHINGTON HAVE HAD DAMAGING WINDS
WITH LOWS SIMILAR TO THIS MAGNITUDE AND TRACK.
SOME OF THE HIGHER RESOLUTION MODELS LIKE THE HRR AND RUC HAVE BACKED
OFF OF THE SURFACE PRESSURE GRADIENT FOR THE WILLAMETTE VALLEY AND WE
MAY SEE WIND GUSTS CLOSER TO 50 MPH THAN 60 MPH...BUT STILL THINK A
FEW LOCATIONS ESPECIALLY NEAR THE FOOTHILLS AND NEWBERG OREGON WILL
RECORD A 60 MPH GUST. DESPITE THE POSSIBLE LOWER WIND GUSTS FOR THE
VALLEY...THE POTENTIAL FOR DAMAGE FROM THE WINDS IS STILL VERY
HIGH..AND THE HIGH WIND WARNING IS STILL ON TRACK.
WE HAVE HAD AT LEAST ONE LIGHTNING STRIKE JUST OFFSHORE THE CENTRAL
OREGON COAST...CONFIRMING ISOLATED THUNDERSTORMS OVER THE WATERS AND
ALONG THE IMMEDIATE COAST AS THE LOW MOVES NORTHWARD JUST WEST OF THE
COAST LINE. THE RAIN WILL BE LETTING UP QUITE A BIT...AND HAVE BACKED
OFF POPS FOR THE WILLAMETTE VALLEY AND THE CASCADE FOOTHILLS THIS
AFTERNOON AND EVENING. THERE WILL STILL BE SHOWERS...BUT MORE
ISOLATED TO SCATTERED THAN WIDESPREAD. TJ
.PREVIOUS SHORT TERM DISCUSSION...THROUGH SATURDAY...CURRENT
SATELLITE LOOP AND SURFACE ANALYSIS PLACES DEEPENING LOW NEAR
41N/129W WITH ESTIMATED MSLP OF 980 MB. IT IS CURRENTLY TRACKING TO
THE NORTH-NORTHEAST WITH THE COMMA CLOUD SHIELD EARLIER THIS EVENING
NOW INTO THE BEGINNING OF A SPIRAL...AN INDICATOR THAT THE LOW STILL
HAS NOT FULLY MATURED. MODEL ESTIMATES LOWEST PRES AROUND 974 TO 978
MB AS THE LOW NEARS PASSES OFF THE SOUTH OREGON COAST THIS
MORNING...THEN BEGINS FILL TO AROUND 980 MB BY TIME IT REACHES THE
SOUTH WASHINGTON COAST LATE THIS AFTERNOON. OVERALL MODELS IN DECENT
AGREEMENT WITH THE EXCEPTION OF THE NAM WHICH CONTINUES TO SHOW A
DOUBLE LOW DEVELOPING OFF THE COAST. THE NAM SOLUTION WOULD DELAY OR
LESSEN THE IMPACT OF HIGH WINDS. GFS/ECMWF SOLUTIONS HAVE BEEN
CONSISTENT AND IN BETTER AGREEMENT AND ACCEPTED. THE ECMWF HAS A
DEEPER LOW OF THE TWO AND TRACK SLIGHTLY WEST OF THE GFS. BOTH MODELS
TRACK THE LOW ABOUT 60-80 MILES OF THE OREGON COAST SO THE WIND AND
PRESSURE FIELDS FOR THE LAND AREAS ARE ABOUT THE SAME. THE
SPEED AND TRACK OF THE LOW SUGGESTS THE WIND SPEEDS WILL RAMP UP
QUICKLY SINCE THE GRADIENT WILL REMAIN EAST TO SOUTHEAST UNTIL THE
LAST MINUTE..EVEN THOUGH THE DURATION OF THE STRONGEST WIND WILL BE
REASONABLY SHORT...SIGNIFICANT IMPACTS SUCH AS DOWNED TREES AND
NUMEROUS POWER OUTAGES...ARE LIKELY.
BASED ON THE LATEST GUIDANCE HAVE FINE TUNED TIMING OF THE HIGH WIND
WARNING HEADLINES. THE MAIN CHANGES WERE TO THE NORTHERN ZONES BY
DELAYING THE START TIME UNTIL THIS AFTERNOON...AND AN EARLIER END FOR
THE SOUTHERN ZONES. ANTICIPATED WIND SPEEDS ON LATEST RUNS ARE A
TOUCH LOWER THAN CURRENT FORECAST SO WILL MAKE SMALL ADJUSTMENT
THERE.STRONGEST WINDS NOW LOOK TO BE LATE MORNING FOR THE CENTRAL
COAST AND MID TO LATE AFTERNOON FOR THE NORTH OREGON/SOUTH WASHINGTON
COAST. FOR INLAND AREAS...THE SOUTH AND CENTRAL ZONES IN THE MID
AFTERNOON...AND MID AFTERNOON TO EARLY EVENING FOR THE NORTHERN ZONES.
THE LOW DEPARTS TO THE NORTH AND WEAKENS TONIGHT WITH DECREASING
SHOWERS. TEMPERATURES WILL REMAIN ON THE WARM SIDE WITH HIGHS IN THE
50S AND LOWS IN THE 40S THROUGH THURSDAY...BEFORE GRADUAL COOLING
FRIDAY THROUGH THE WEEKEND. THUNDERSTORMS ARE STILL POSSIBLE WITH AS
AN COOL UPPER TROUGH TRANSITS THE WATERS TONIGHT AND INLAND
ON FRIDAY.
A SHORT WAVE RIDGE WILL MOVE OVER THE PACIFIC NW FRIDAY NIGHT
RESULTING IN DRY WEATHER FOR AT LEAST THE FIRST HALF OF THE WEEKEND.
WITH LIGHT WINDS...INCREASING SUBSIDENCE...AND CLEARING SKIES EXPECT
SOME FOG IN THE INTERIOR VALLEYS FRIDAY NIGHT AND SATURDAY MORNING.
WEISHAAR/MH
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...SATURDAY NIGHT
THROUGH TUESDAY NIGHT...HIGH PRESSURE BUILDS OVER THE PACIFIC
NORTHWEST SATURDAY NIGHT THROUGH THE DAY ON SUNDAY...WHICH WILL KEEP
CONDITIONS DRY. EASTERLY WINDS PICK UP ON SUNDAY AHEAD OF THE NEXT
FRONTAL SYSTEM...WHICH APPROACHES LATE SUNDAY OR MONDAY. EASTERLY
WINDS WILL CAUSE TEMPERATURES TO BE COOLER ON SUNDAY AND MONDAY. THE
FIRST CHANCE OF RAIN COMES AS THE WARM FRONT MOVES THROUGH ON MONDAY
OR TUESDAY. THERE IS SOME DISCREPANCY BETWEEN THE MODELS ON THE
TIMING OF THIS FRONT. THE COLD FRONT WITH THIS SYSTEM MOVES THROUGH
18 TO 24 HOURS BEHIND THE WARM FRONT. PARADE OF FRONTS LOOK LIKELY TO
CONTINUE THROUGH NEXT WEEK. -MCCOY
&&
.AVIATION...AN INTENSE LOW PRESSURE SYSTEM WILL BRING WINDY
CONDITIONS THIS AFTERNOON AND EVENING...AND MAINLY VFR CONDITIONS
FOR MOST TAF SITES THROUGH 18Z FRIDAY. EXPECT STRONG SOUTH WINDS TO
DEVELOP THIS AFTERNOON. WIND GUSTS OF 50-70 KT APPEAR LIKELY ALONG
THE COAST...WITH WIND GUSTS GENERALLY IN THE 40 TO 45 KT RANGE FOR
INTERIOR TAF SITES. EXPECT SOUTHERLY TAF SITES TO PEAK BETWEEN 19Z
AND 23Z THURSDAY...AND 22Z THURSDAY AND 03Z FRIDAY FOR MORE
NORTHERLY TAF SITES. COASTAL LOCATIONS COULD SEE SOME TEMPORARY
LOWER MVFR CEILINGS AND VISIBILITIES TODAY. AS WINDS SLACKEN LATE
TONIGHT...FLIGHT RESTRICTIONS MAY DEVELOP AT SEVERAL TAF SITES
BETWEEN 12Z AND 18Z FRIDAY...BUT UNCERTAINTY IS HIGH.
KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH 18Z
FRIDAY. THERE IS A CHANCE LOWER FLIGHT CONDITIONS MAY DEVELOP AFTER
12Z FRIDAY. EAST WINDS WILL SHIFT ABRUPTLY TO SOUTHERLY THIS
AFTERNOON AND INCREASE SUBSTANTIALLY WITH GUSTS OF 40 TO 45 KT
POSSIBLE. THIS WIND SHIFT WILL MOST LIKELY OCCUR BETWEEN 22Z
THURSDAY AND 00Z FRIDAY. EXPECT THE STRONGEST SOUTHERLY WINDS TO END
BY 03Z FRIDAY. /NEUMAN
&&
.MARINE...RAPIDLY DEVELOPING LOW GENERALLY ON TRACK WITH REGARD
TO POSITION. STILL LOOKS LIKE THE LOW PRESSURE CENTER WILL TRACK
NORTH NEAR OR JUST OUTSIDE OUR WATERS AT 50 TO 80 NM OFFSHORE.
RECENT MODEL RUNS HAVE MAINTAINED A SIMILAR STRENGTH TO PAST RUNS
BUT WE ARE NOW WELL WITHIN THE WINDOW OF THE HRRR FORECAST WINDOW.
A SHIP REPORT IN THE NORTHEAST SECTOR OF THE LOW HAS PROVED
INVALUABLE IN CONFIRMING SOME HIGHER WIND SPEEDS SHOWN BY THE HRRR
MODEL. SUSTAINED SPEEDS EAST OF THE LOW ARE MODELED TO BE IN THE
40 TO 45 KT RANGE WITH SOUTHEAST QUADRANT WINDS 50 TO 55 KT. MOST
INTERESTINGLY...THE HRRR MODELS GUSTS REACHING INTO THE 65 TO 75
KT TERRITORY AND HAVE THUS DECIDED TO UPGRADE THE STORM WARNING
TO A HURRICANE FORCE WIND WARNING. FEEL THOSE WINDS WILL LARGELY
BE WITHIN 30 NM OF SHORE AS THE AIR GETS PACKED UP AGAINST THE
COAST RANGE TERRAIN AND ACCELERATED. WINDS OUTSIDE OF 30 NM WILL
STILL BE ON THE HIGHER END OF STORM FORCE AS WELL. ALSO FEEL THE
LOW WILL WEAKEN ENOUGH SUCH THAT GUSTS NORTH OF THE COLUMBIA RIVER
WILL STAY AROUND A 60 KT MAXIMUM.
EXPECT THE STRONGEST STORM FORCE WINDS TO DEVELOP OFF THE COAST
OF NEWPORT AROUND NOON TODAY...AND BY AROUND 5 PM OFF THE COAST OF
ASTORIA. STEEP SEAS WILL DEVELOP RAPIDLY WITH THE ONSET OF HIGH
WINDS...WITH PEAK SEAS EXPECTED TO APPROACH 30 FT THIS AFTERNOON.
AS THE LOW MOVES UP CLOSE OFF THE WA COAST THIS EVENING THE STORM
IS EXPECTED TO WEAKEN SOME. AS SUCH...EXPECT WINDS TO DIMINISH
OVERNIGHT...WITH SEAS FOLLOWING SHORTLY THEREAFTER. AFTER 1 AM
EXPECT MOST OF THE COASTAL WATERS TO BE BACK DOWN TO SMALL CRAFT
WINDS...WITH SEAS DROPPING BELOW 20 FT AFTER 4 AM.
EXPECT MUCH QUIETER WEATHER TO FOLLOW FRI AND FOR SEVERAL DAYS
AFTER. NEXT CHANCE FOR WINDS TO GET UP TO SMALL CRAFT CRITERIA COMES
SUN...WITH SEAS IN THE 11 TO 14 FT RANGE FRI LOWERING BELOW 10 FT
SUN. /JBONK
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING FOR CASCADE
FOOTHILLS IN LANE COUNTY-CENTRAL WILLAMETTE VALLEY-NORTHERN
OREGON CASCADE FOOTHILLS-SOUTH WILLAMETTE VALLEY.
HIGH WIND WARNING FROM 2 PM THIS AFTERNOON TO 10 PM PST THIS
EVENING FOR GREATER PORTLAND METRO AREA-LOWER COLUMBIA.
HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING FOR CENTRAL COAST
RANGE OF WESTERN OREGON-CENTRAL OREGON COAST.
HIGH SURF ADVISORY UNTIL 10 PM PST THIS EVENING FOR CENTRAL
OREGON COAST-NORTH OREGON COAST.
HIGH WIND WARNING FROM 1 PM THIS AFTERNOON TO 10 PM PST THIS
EVENING FOR COAST RANGE OF NORTHWEST OREGON-NORTH OREGON
COAST.
WA...HIGH WIND WARNING FROM 2 PM THIS AFTERNOON TO 10 PM PST THIS
EVENING FOR GREATER VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ
COUNTY-SOUTH WASHINGTON CASCADE FOOTHILLS.
HIGH SURF ADVISORY UNTIL 10 PM PST THIS EVENING FOR SOUTH
WASHINGTON COAST.
HIGH WIND WARNING FROM 1 PM THIS AFTERNOON TO 10 PM PST THIS
EVENING FOR SOUTH WASHINGTON COAST-WILLAPA HILLS.
PZ...HURRICANE FORCE WIND WARNING UNTIL 7 PM PST THIS EVENING FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL NOON PST
FRIDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS MEDFORD OR
905 AM PST THU DEC 11 2014
.DISCUSSION...
LOW PRESSURE CURRENTLY 140 MILES WEST OF CAPE BLANCO HAS A
CONFIRMED CENTRAL PRESSURE BELOW 980 MB PER A 15Z SHIP REPORT 60
MILES WEST OF BROOKINGS. THIS STRONG LOW PRESSURE SYSTEM,
ESPECIALLY FOR IT`S LOCATION AND PROXIMITY TO THE COAST, IS LIKELY
AT OR NEAR IT`S LOWEST CENTRAL PRESSURE, NEAR 975MB. THE LOW WILL
CONTINUE MOVING NORTHEASTWARD THROUGH THE DAY TODAY, WITH STRONG
WINDS ALONG THE COAST AND COASTAL WATERS LIKELY BEGINNING TO
DIMINISH SOUTH OF CAPE BLANCO AFTER 21Z AND NORTH OF CAPE BLANCO
AFTER 00Z.
INLAND, PRESSURE GRADIENTS HAVE LIKELY REACHED THEIR PEAK ON THE
WEST SIDE, BUT MAXIMUM WINDS ALOFT WILL CONTINUE TO PEAK BETWEEN
18Z AND 21Z ACROSS THE AREA, LAST FURTHEST EAST ACROSS MODOC AND
LAKE COUNTIES. PEAK WINDS IN THE ROGUE AND SHASTA VALLEYS, THUS
FAR, THIS MORNING, HAVE BEEN IN THE 50 TO 70 MPH RANGE WITH
NUMEROUS POWER OUTAGES REPORTED IN THE ASHLAND, MEDFORD, GRANTS
PASS, AND ROSEBURG AREAS. IN THE MOUNTAINS SQUAW PEAK REPORTED A
GUST TO 117 MPH EARLIER THIS MORNING.
AS FAR AS PRECIPITATION GOES, THERE HAVE BEEN SOME IMPRESSIVE
TOTALS, THUS FAR. MOUNT SHASTA CITY HAS RECEIVED 4 TO 5 INCHES OF
RAIN IN THE LAST 24 HOURS. UP ON THE VOLCANO, AT THE AVALANCHE
CENTER`S OLD SKI BOWL SENSOR, 17.5 INCHES OF NEW SNOW HAS FALLEN.
SNOW LEVELS MEANDERED BETWEEN ABOUT 6000 AND 7000 FEET OVER THE
LAST 12 HOURS, WITH MOUNT ASHLAND REPORTING 3-5 INCHES THIS
MORNING.
IN SHORT, ADVISORIES AND WARNINGS WILL CONTINUE INTO THE AFTERNOON
ACROSS THE FORECAST AREA AS THE STRONG LOW CONTINUES TO MOVE BY.
EXPECT CONDITIONS TO SETTLE DOWN OVERNIGHT. NO UPDATES NEEDED, THUS
FAR, THIS MORNING. WE`LL BE MAKING UPDATES THROUGH DAY AS
THE SITUATION WARRANTS. BTL
&&
.AVIATION...BASED ON THE 11/12Z TAF CYCLE...WINDS ARE ON THE
INCREASE AGAIN AS STRONG LOW PRESSURE MOVES NEAR THE COAST. MODERATE
TO STRONG WINDS ARE GOING TO BE THE MAIN CONCERN FOR ALL TERMINALS
THURSDAY, WITH LOW LEVEL WIND SPEED SHEAR PROBLEMATIC WEST OF THE
CASCADES. IT WILL BE A CLOSE CALL FOR WIND SPEED SHEAR AT KLAMATH
FALLS, BUT ONLY BECAUSE SURFACE WIND SPEEDS THERE WILL BE STRONG
ENOUGH TO NEGATE MEETING CRITERIA. VFR CIGS ARE EXPECTED, BUT LOCAL
MVFR CIGS/VSBYS ARE POSSIBLE IN HEAVIER RAIN. TERRAIN OBSCURATION IS
EXPECTED IN ALL AREAS. WINDS WILL DECREASE THIS EVENING, BUT RAIN
CHANCES WILL CONTINUE THROUGHOUT THE TAF PERIOD. -BPN/PETRUCELLI
&&
.MARINE...UPDATED 200 AM PST THU DEC 11 2014...WINDS WILL INCREASE
THROUGH THIS MORNING AS A SURFACE LOW DEEPENS OFFSHORE, THEN MOVES
NORTH THROUGH THE COASTAL WATERS THIS AFTERNOON. EXPECT ANOTHER
ROUND OF STORM FORCE WINDS, WITH HURRICANE FORCE GUSTS
POSSIBLE, ESPECIALLY IN THE VICINITY OF CAPE BLANCO.
MEANWHILE...HEAVY LONG PERIOD WEST SWELL WILL COMBINE WITH STRONG
SOUTHERLY CHOP TO PRODUCE VERY STEEP AND HAZARDOUS SEAS THROUGH THIS
AFTERNOON. COMBINED SEAS WILL BUILD TO HEIGHTS IN EXCESS OF 25 FEET,
WITH BREAKING WAVES OF OVER 30 FEET EXPECTED NEAR SHORE,
SHOALS, AND OTHER SHALLOW WATER AREAS.
THIS WILL BE A VERY STRONG STORM. ALL MARITIME AND COASTAL INTERESTS
SHOULD TAKE ALL PRECAUTIONS NECESSARY TO PRESERVE LIFE AND
PROPERTY...AS SIGNIFICANT DAMAGE IS POSSIBLE TO UNSECURED AND
EXPOSED EQUIPMENT AND INFRASTRUCTURE. IT IS STRONGLY RECOMMENDED
THAT ALL VESSELS REMAIN IN SAFE HARBOR UNTIL CONDITIONS IMPROVE THIS
EVENING.
BEYOND THURSDAY...WINDS WILL DIMINISH...BUT UNSETTLED WEATHER WILL
CONTINUE THROUGH THE NEXT WEEK. SEAS WILL GRADUALLY SUBSIDE THROUGH
THE NEXT SEVERAL DAYS, REMAINING ABOVE SMALL CRAFT CRITERIA THROUGH
AT LEAST SATURDAY. EXPECT ANOTHER ROUND OF STRONG WINDS AND HEAVY
SEAS AS THE NEXT FRONTAL SYSTEM ENTERS THE COASTAL WATERS THIS
WEEKEND. THERE IS ALSO THE POTENTIAL FOR HEAVY LONG PERIOD SWELL TO
RETURN TO THE AREA EARLY NEXT WEEK. -BPN
&&
.PREV DISCUSSION... /ISSUED 408 AM PST THU DEC 11 2014/
SHORT TERM...A STRONG LOW PRESSURE IS LOCATED ABOUT 250 MILES
OFF THE OREGON CALIFORNIA COAST BORDER. THIS LOW PRESSURE IS
FORECAST TO APPROACH THE SOUTHERN OREGON COAST THIS MORNING AND
MOVE NORTH ALONG THE OREGON COAST DURING THE AFTERNOON. THIS LOW
IS FORECAST TO BE AROUND 975 TO 980 MB AS IT NEARS THE SOUTHERN
OREGON COAST TODAY. IT WILL BRING A STRONG PRESSURE GRADIENT
AS WELL AS STRONG LOW AND MID LEVEL JETS INTO THE AREA...RESULTING
IN VERY STRONG GUSTY WINDS DEVELOPING OVER MUCH OF THE AREA THIS
MORNING INTO THIS AFTERNOON.
WINDS HAVE BEGUN TO INCREASE EARLY THIS MORNING WITH GUSTY SOUTH
TO SOUTHEAST WINDS DEVELOPING ALONG THE COAST, OVER THE MOUNTAINS
AND INLAND INTO SOME VALLEY LOCATIONS, INCLUDING THE SHASTA AND
ROGUE VALLEYS. OBSERVATIONS ALSO SHOW GALE FORCE WINDS DEVELOPING
IN THE SOUTHERN COASTAL WATERS EARLY THIS MORNING. WINDS ARE
EXPECTED TO RISE TO STORM FORCE IN THE COASTAL WATERS WITH AREAS
OF HIGH WINDS EXPECTED ALONG THE COAST AND INLAND.
CURRENT MODELS ARE IN GOOD AGREEMENT WITH THE TIMING AND TRACK OF
THE LOW AND SHOW THIS LOW APPROACHING WITHIN 100 NM OF THE COAST,
CENTERED OFF CAPE BLANCO BY LATE THIS MORNING. THEN SHIFTING
NORTH DURING THE AFTERNOON ALONG THE CENTRAL OREGON COAST. THE
NAM REMAINS SLIGHTLY SLOWER THAN THE OTHER MODELS WITH THE TRACK
OF THIS LOW AND HAVE LEANED TOWARDS A COMBINATION OF THE GFS AND
ECMWF AS WELL THE HIGH RESOLUTION NMW AND RAP MODELS. THESE
MODELS BRING A SOUTH 70 TO 80 KT 925 MB JET ALONG THE COAST WITH
THE PASSAGE OF THE LOW. THIS WILL ALLOW HIGH WINDS TO DEVELOP IN
COASTAL AREAS, INITIALLY ALONG THE SOUTH COAST EARLY THIS
MORNING, THEN SPREADING ALONG THE ENTIRE SOUTHERN OREGON COAST IN
THE MID TO LATE MORNING AND CONTINUING INTO THE AFTERNOON. PEAK
WINDS ALONG THE COAST ARE EXPECTED TO BE AROUND 40 TO 55 MPH WITH
FREQUENT GUSTS OF 60 TO 70 MPH AND OCCASIONAL GUSTS TO 80 MPH OR
POSSIBLY HIGHER. WINDS ARE EXPECTED TO DECREASE FROM SOUTH TO
NORTH IN THE MID TO LATE AFTERNOON ALONG THE COAST.
INLAND AREAS WILL ALSO SEE STRONG GUSTY WINDS THIS MORNING INTO
THIS AFTERNOON AS A MID LEVEL JET OF AROUND 80 KT MOVES OVER THIS
AREA THIS MORNING INTO THIS AFTERNOON. STRONGEST WINDS ARE
EXPECTED IN THE SHASTA VALLEY, SOUTHERN ROGUE VALLEY, OVER THE
CASCADES AND SISKIYOUS, AND EAST OF THE CASCADES. THESE AREAS ARE
EXPECTED TO EXPERIENCE VERY STRONG, AND POTENTIALLY DAMAGING,
WINDS GUSTING TO AROUND 60 TO 70 MPH AND LOCALLY HIGHER. ALTHOUGH
THESE AREAS WILL SEE THE STRONGEST WINDS AND GREATEST IMPACTS,
EXPECT MOST THE AREA TO SEE VERY GUSTY WINDS TODAY. WIND WARNINGS
AND WIND ADVISORIES ARE IN PLACE THROUGH THIS AFTERNOON ACROSS
MOST THE AREA.
IN ADDITION TO STRONG GUSTY WINDS, MODERATE TO LOCALLY HEAVY RAIN
WILL MOVE INTO THE AREA WITH THIS LOW PASSAGE. THIS MAY BRING THE
POTENTIAL FOR FLOODING IMPACTS TO WESTERN PORTIONS OF THE AREA.
AN AREAL FLOOD WATCH REMAINS IN EFFECT FOR COASTAL AREAS AND A
FLASH FLOOD WATCH IS IN EFFECT FOR THE WILDFIRE BURN SCARS IN
WESTERN SISKIYOU. MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED THIS
MORNING ALONG THE COAST, ESPECIALLY IN CURRY COUNTY. THIS RAIN
COMBINED WITH RAINFALL FROM YESTERDAYS STORM, MAY ALLOW FOR SMALL
STREAM OR LOCALIZED URBAN FLOODING ALONG THE COAST. IN WESTERN
SISKIYOU COUNTY, MODERATE TO HEAVY RAINFALL IS ALSO EXPECTED THIS
MORNING AND MAY BRING THE POTENTIAL FOR FLASH FLOODING IN THE
WILDFIRE BURN SCAR AREAS.
THIS EVENING AND TONIGHT, WINDS ARE EXPECTED TO DIMINISH OVER THE
AREA AS THE LOW SHIFTS NORTH. AN UPPER TROUGH WILL PUSH INTO THE
AREA FROM THE WEST THIS EVENING INTO FRIDAY. THIS WILL BRING A
COOL AND SHOWERY AIR MASS TO THE AREA THROUGH FRIDAY.
SNOW LEVELS ARE EXPECTED TO LOWER FROM 7000 FEET THIS MORNING TO
AROUND 6000 FT THIS AFTERNOON AS COLD AIR MOVES INTO THE AREA
BEHIND THE LOW. THEN AS AN UPPER TROUGH PUSHES INLAND TONIGHT
EXPECT SNOW LEVELS TO LOWER DOWN TO 5000 FT...WITH SNOW LEVELS OF
AROUND 4500 TO 5000 FT ON FRIDAY. THESE LOWER SNOW LEVELS
COMBINED WITH SHOWER ACTIVITY WILL BRING SOME LIGHT SNOW
ACCUMULATIONS TO HIGHER ELEVATIONS. UPPER MOUNTAINS, ABOVE 7000
FT ELEVATION, WILL SEE SIGNIFICANT SNOW AMOUNTS TODAY INTO
TONIGHT.
THE COLD AIR ALOFT ASSOCIATED WITH THE LOW WILL ALSO BRING A
CHANCE OF ISOLATED THUNDERSTORMS TO THE COAST AND COASTAL WATERS
TODAY. THEN AS THE UPPER TROUGH MOVES INTO THE AREA, EXPECT THIS
SLIGHT CHANCE FOR THUNDERSTORMS TO EXTEND INLAND TONIGHT INTO
FRIDAY INTO AREAS WEST OF THE CASCADES.
PREV LONG TERM DISCUSSION... /ISSUED 252 PM PST WED DEC 10 2014/
LONG TERM...FRIDAY THROUGH WEDNESDAY...ON FRIDAY A BROAD UPPER
TROUGH WILL REMAIN OVER THE NORTHWEST WITH SCATTERED TO NUMEROUS
SHOWERS AND SNOW LEVELS BETWEEN 4500-5000 FEET. COULD SEE UP TO A
FEW INCHES OF ACCUMULATION OVER THE HIGHER TERRAIN EAST OF THE
CASCADES. THERE IS SOME UNCERTAINTY WITH POTENTIALLY HIGHER SNOW
AMOUNTS AS A SURFACE LOW SHOULD TRACK SOUTH TO NORTH INTO SOUTHEAST
OREGON WITH POTENTIAL HEAVIER AMOUNTS OVER LAKE COUNTY. COULD NEED
TO BUMP TOTALS THERE IN UPCOMING FORECASTS. FRIDAY NIGHT THROUGH
SATURDAY THINGS WILL SETTLE DOWN CONSIDERABLY WITH SOME MORNING
VALLEY FOG DEVELOPING IN AREAS UNDER SHORTWAVE RIDGING. BOTH THE
EURO AND GFS SOLUTIONS ARE BRINGING IN ANOTHER UPPER TROUGH TO THE
COAST LATER SUNDAY THROUGH MONDAY WITH SHOWER CHANCES INCREASING
MAINLY ACROSS THE COAST AND NORTHWEST CALIFORNIA. THIS TROUGH SHOULD
TRAVERSE THE REGION MONDAY NIGHT THROUGH TUESDAY WITH SHOWERS
BECOMING MORE NUMEROUS. ADDITIONAL SHORT WAVE ENERGY WILL TARGET THE
NORTHWEST WITH A FAIR DEGREE OF UNCERTAINTY IN TIMING OF EVENTS AT
THIS POINT. SOLUTIONS ARE POINTING TO THE POTENTIAL FOR UP TO A
COUPLE BOUTS OF GUSTY SOUTH WINDS AT THE COAST MONDAY-TUESDAY.
STAVISH
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ029>031-624-625.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ021-022-615-618-619.
FLOOD WATCH UNTIL 1 PM PST THIS AFTERNOON FOR
ORZ021>024-615-616-618-619.
HIGH SURF ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ021-022-615-618-619.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
ORZ023-025-616-617-620-623.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR
ORZ027-028-617-621-623.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR ORZ026-622.
CA...HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
CAZ083>085-284-285.
FLASH FLOOD WATCH UNTIL 10 AM PST THIS MORNING FOR
CAZ080-081-280-281.
HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR CAZ081-281.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 PM THIS EVENING
TO 4 AM PST SUNDAY FOR PZZ350-356-370-376.
STORM WARNING UNTIL 4 PM PST THIS AFTERNOON FOR
PZZ350-356-370-376.
HAZARDOUS SEAS WARNING UNTIL 10 PM PST THIS EVENING FOR
PZZ350-356.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR PZZ310.
FLOOD WATCH UNTIL 1 PM PST THIS AFTERNOON FOR PZZ310.
HAZARDOUS SEAS WARNING UNTIL 10 PM PST THIS EVENING FOR
PZZ370-376.
$$
BTL/BTL/BTL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1254 PM EST THU DEC 11 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL SPIN OVER THE NORTHEASTERN UNITED STATES
THROUGH SATURDAY. NORTHWEST FLOW OFF THE LAKES AND EVEN SOME
MOISTURE WRAPPING ALL THE WAY AROUND THE LOW WILL CREATE LIGHT
BUT NEARLY CONSTANT SNOW OVER THE NORTHERN MOUNTAINS AND
ALLEGHENIES INTO FRIDAY. RIDGING AND HIGH PRESSURE WILL SLOWLY
TRANSLATE EASTWARD TO REPLACE THE UPPER LOW OVER THE WEEKEND.
TEMPERATURES WILL MODERATE AND THE WEATHER REMAIN
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
COLD CONVEYOR BELT DEFORMATION SNOWFALL WITH SEVERAL EXTENSIVE
AND ENHANCED NW/SE BANDS CONTINUES TO IMPACT MUCH OF CENTRAL AND
EASTERN PA AT DAYBREAK. HIGH RES WRF ARW AND HRRR INDICATE THE
LIKELIHOOD OF THE BANDS PIVOTING A BIT MORE TO THE SOUTH THIS
MORNING...AND STAYING FOCUSED CLOSE TO THE RT 322 CORRIDOR...AND
POINTS TO THE EAST IN CENTRAL PENN. DUE TO MODEL AND UPPER AIR SOUNDINGS
THERE IS A POCKET OF WARM AIR ALOFT...ESPECIALLY IN AREAS OF WEAK
FORCING. DUE TO THIS AREAS OF FREEZING DRIZZLE REMAINS POSSIBLE AS
SOUTH AS BLAIR...HUNTINGDON AND CAMBRIA COUNTIES. BLACK ICE IS
POSSIBLE ON UNTREATED SURFACES WHICH COULD MAKE DRIVING
HAZARDOUS.
EXPANDED THE WINTER WEATHER ADVISORY FURTHER WEST AND SOUTH TO
INCLUDE THE LAURELS AND CENTRAL MOUNTAINS...ALSO ACROSS MUCH OF
THE LOWER SUSQ VALLEY /WHILE ALSO EXTENDING IT IN TIME THROUGH 18Z
TODAY/.
NUMEROUS REPORTS OF 2-4 INCHES OVERNIGHT ACROSS THE CENTRAL MTNS
AND SUSQ VALLEY. EXPECT AT LEAST ANOTHER INCH OR TWO OF SNOW TO
FALL INTO THE EARLY AFTERNOON WITH LOCALIZED ADDITIONAL 3 INCH
AMOUNTS. HEAVIER...AND MORE PERSISTENT SYNOPTIC/COLD CONVEYOR
SNOWS WILL DRIFT ACROSS THE NW MTNS AND STAY THERE INTO EARLY
THIS EVENING...WITH LAKE AND OROGRAPHIC ENHANCEMENT CAUSING 3 OR 4
INCHES TO FALL TODAY /IN ADDITION TO THE FEW INCHES OVERNIGHT.
TOTAL SNOW MAY BE TEETERING ON 24 HOUR WARNING CRITERIA OF 8
INCHES NEAR AND TO THE WEST OF KBFD BY THIS AFTERNOON.
TO COMPLICATE MATTERS...AREAS OF FREEZING DRIZZLE HAVE OCCURRED
DURING LULLS IN THE SNOWFALL /I.E. BETWEEN THE SLOWLY SWWD
DRIFTING SNOW BANDS/.
PREVIOUS DISCUSSION...
THE PRIMARY CONCERN FOR SIGNIFICANT SNOW WILL SHIFT TO THE NW
MTNS...AND PERHAPS SOME LOCATIONS AS FAR SE AS THE ALLEGHENY FRONT
IN CENTRAL PENN LATE THIS MORNING AND THIS AFTERNOON. MEAN SFC-850
MB FLOW WILL BACK ANOTHER 10-15 DEG TODAY /TO AROUND 310
DEG/...AND THE HEIGHT OF THE SUBSIDENCE INVERSION RISES TO AROUND
5 KFT AGL. THIS FAVORABLE THERMAL...AND SHEAR PROFILE WITH MDTLY
STRONG WINDS OF 30-40 KTS IN THE 2-5 KFT AGL LAYER WILL HELP TO
FORM AND DIRECT SOME WELL-DEFINED SNOW BANDS WELL INLAND.
ADDITIONAL SNOWFALL OF 4-6 INCHES CAN BE EXPECTED INVOF KFD OVER
THE NEXT 15 HRS.
HIGH TEMPS TODAY WILL ONLY RISE ABOUT 3-4F FROM THEIR EARLY
MORNING LOWS - AROUND 20F ACROSS THE NRN AND WRN MTNS...AND MID TO
UPPER 20S ELSEWHERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
THE PLUME OF DEEP MOISTURE/SNOWFALL GETS WEAKER AS THE UPPER LOW
STARTS TO SLIDE TO THE EAST TOWARD THE NEW ENG COAST.
THEREFORE...THERE SHOULD BE A DIMINISHING INTENSITY AND COVERAGE
TO THE SNOW...AND MAINLY JUST LAKE EFFECT LEFT FOR TONIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
THE LOW WILL CONTINUE TO MOVE SLOWLY NORTHWARD...WITH
PRECIPITATION POSSIBLE IN MINOR ACCUMULATIONS INTO FRIDAY MORNING.
HOWEVER ONCE THE NORTHWESTERLY FLOW CUTS OFF EARLY FRIDAY...THE
PRECIP WILL FADE WITH ONLY THE NW MTNS STILL RECEIVING LIGHT
SNOWFALL.
THE LATEST MID TO LONG RANGE MODELS ARE IN FAIR AGREEMENT INTO
FRIDAY NIGHT BUT THEN BEGIN TO DIVERGE ON THE TIMING AND MOVEMENT
OF THE LARGE UPPER LEVEL LOW. THE NAM AND GEFS ENSEMBLES HAS IT
STALLING OVER THE NORTHEAST...AND THEN DIVING SOUTHEASTWARD.
HOWEVER THE LATEST GFS AND EC GUIDANCE ARE IN DECENT AGREEMENT FOR
THE UPPER LOW TO NUDGE EASTWARD AND CONTINUE TO MOVE TO THE
NORTHEAST. THROUGH THIS TIMEFRAME A RIDGE WILL BUILD OVER THE
GREAT LAKES AND SLOWLY MOVE EASTWARD. THIS WILL BRING WARMER
TEMPERATURES AND MILD WEATHER FOR THE REGION THROUGH THE WEEKEND
AND INTO EARLY NEXT WEEK. A WARMER PATTERN WILL CONTINUE THROUGH
THE FIRST HALF OF NEXT WEEK WITH THE NEXT CHANCE FOR PRECIPITATION
BEING TUESDAY INT WEDNESDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SEVERAL BANDS OF MODERATE TO HEAVY SNOW MIGRATING ACROSS CENTRAL
PENNSYLVANIA EARLY THIS AFTERNOON WILL KEEP HIGHLY VARIABLE
CONDITIONS ACROSS CENTRAL AND WESTERN AIRFIELDS THROUGH 00Z. IN
THE BANDS OF HEAVIEST SNOW...LIFR WITH VISIBILITIES 1/4 MILE OR
LESS CAN BE EXPECTED...WHEREAS OUTSIDE THESE INTENSE
BANDS...GENERALLY MVFR CONDITIONS WILL PREVAIL.
LATEST TAF PACKAGE TRIES TO CAPTURE THIS...BUT HIGH VARIABLILITY
OF CONDITIONS WILL LIKELY REQUIRE ADJUSTMENTS THROUGH THE DAY.
OVERALL...IMPROVING TREND EXPECTED IN MOST LOCATIONS LATER TODAY
AND OVERNIGHT. HOWEVER...SNOW WILL LINGER IN THE HIGHLANDS /KBFD
AND KJST/ INTO TOMORROW DUE TO OROGRAPHIC EFFECTS.
GUSTY WINDS WILL CONTINUE TODAY...BUT AGAIN SLOWLY DIMINISH OVER
THE NEXT 18 TO 24 HOURS. INCLUDED LLWS IN KIPT TAF AS THEIR
SURFACE WINDS ARE LIGHT AND VARIABLE...AND WINDS ALOFT HAVE NOT
MIXED TO THE GROUND AT THE AIRPORT.
CONDITIONS IMPROVE FOR FRIDAY INTO THE WEEKEND...AS HIGH PRESSURE
BUILDS EASTWARD FROM THE PLAINS.
OUTLOOK...
FRI...MVFR/IFR IN -SHSN NORTH/WEST. MAINLY VFR CENTRAL AND EAST.
SAT...MVFR CIGS/-SHSN EARLY WEST...BCMG VFR.
SUN-MON...GENERALLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
PAZ006-010>012-017>019-024>028-037-041-042-045-046-051-053-056-
057-059-066.
WINTER STORM WARNING UNTIL 3 PM EST THIS AFTERNOON FOR PAZ049-
050-052-058.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ005.
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR PAZ004.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT/CERU
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/LAMBERT
AVIATION...JUNG/EVANEGO