Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/03/14
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1158 PM CST SUN NOV 30 2014
.AVIATION...01/06Z TAF CYCLE
THE COLD FRONT IS NOW ACROSS NORTHERN ARKANSAS FORT SMITH TO EVENING
SHADE. WINDS WILL TURN TO THE NORTH BEHIND THE FRONT. ALSO MUCH
COLDER AIR WILL BE USHERED IN WITH THE FRONT. DRIZZLE AND SLEET WILL
TURN TO FREEZING DRIZZLE IN THE NORTH THIS COMING MORNING. LIGHT
RAIN IS EXPECTED CENTRAL AND SOUTH. ALSO...CEILINGS WILL BE LOWERING
THROUGH THE NIGHT. VFR CONDITIONS WILL BECOME MAINLY MVFR AND
PERSIST FOR MOST OF THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 937 PM CST SUN NOV 30 2014/
UPDATE...
NO APPRECIABLE CHANGES WILL BE FORTH COMING THIS EVENING. LATEST
SURFACE ANALYSIS SHOWS THE COLD FRONT HAS CLEARED NORTHWEST
ARKANSAS WITH TEMPERATURES ALREADY DOWN IN THE UPPER 30S IN BENTON
COUNTY. LZK 00Z SOUNDING SHOWS CONSIDERABLE LAYER OF DRY AIR JUST
OFF THE DECK BUT KSGF RAOB IS MOISTENING UP. WOULD NOT BE
SURPRISED TO SEE AS LITTLE SLEET MIXED IN BASED ON THIS SOUNDING.
PRECIP CHANCES MAY BE DELAYED A SHORT TIME BUT HRRR AND NEW NAM
DOES SHOW PRECIPITATION STARTING OVER THE NEXT FEW HOURS. TIMING
AND PLACEMENT OF THE WINTER WEATHER ADVISORY STILL LOOK GOOD AND
AMOUNTS OF ACTUAL ICE STILL LOOK TO BE UNDER A TENTH OF AN INCH.
PRIMARY CONCERN WILL REMAIN ELEVATED SURFACES.
PREV DISCUSSION... /ISSUED 248 PM CST SUN NOV 30 2014/
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
THE MAIN CONCERN FOR THE SHORT TERM IS THE IMPENDING WINTER
WEATHER SLATED TO AFFECT THE NORTHERN PARTS OF ARKANSAS TONIGHT.
AS SUCH THE DISCUSSION WILL FOCUS PRIMARILY ON THAT.
REGIONAL SURFACE ANALYSIS SHOWS A STARK COLD FRONT SITUATED FROM
SOUTH OF OKLAHOMA CITY...THROUGH SOUTH OF TULSA...AND THROUGH
ROUGHLY THE SPRINGFIELD MISSOURI AREA THIS AFTERNOON. THIS FRONT
WILL CREEP SOUTHWARD THROUGH ARKANSAS OVER THE NEXT 24 HOURS OR
SO...FINALLY PUSHING SOUTH OF THE STATE BY MONDAY EVENING. FROPA
SHOULD BE OCCUR JUST BEFORE MIDNIGHT TONIGHT AT HARRISON...AROUND
DAYBREAK AT PLACES LIKE LITTLE ROCK...MOUNT IDA...AND
CLARENDON...AND FINALLY BY EARLY AFTERNOON IN THE FAR SOUTH. AHEAD
OF THE FRONT UNSEASONABLY WARM AND HUMID CONDITIONS HAVE BEEN SEEN
THIS WEEKEND...WITH HIGHS TODAY RISING INTO THE UPPER 70S IN
PLACES. CONVERSELY...HIGHS FOR MANY PLACES TOMORROW WILL BE DURING
THE EARLY MORNING HOURS...WITH TEMPERATURES FALLING INTO THE MID
30S BEHIND THE FRONT DURING THE DAY MONDAY. MEANWHILE...A WEAK
DISTURBANCE WILL BEGIN TO APPROACH FROM THE WEST LATER TODAY AND
EVENTUALLY MOVE EAST OF THE STATE BY MON EVENING...RESULTING IN
LIGHT PRECIP ACROSS THE FORECAST AREA FROM LATE TONIGHT THROUGH
THE DAY MONDAY.
INITIALLY THIS WILL BEGIN AS RAIN...BUT AS THE AFOREMENTIONED COLD
FRONT BEGINS TO PUSH INTO ARKANSAS FROM THE NORTH...THE POST
FRONTAL AIR SHOULD BE SUFFICIENTLY COLD AND DEEP ENOUGH TO CHANGE
PRECIPITATION TO MAINLY FREEZING RAIN. ONE CAVEAT WOULD BE THAT
THERE ARE SOME CONVECTIVE ELEMENTS NOTED IN MODEL OUTPUT SO I
WOULD NOT BE SURPRISED TO SEE SOME SLEET DEVELOP IN
PLACES...MAINLY IN NORTH CENTRAL AND NORTHEAST ARKANSAS TOMORROW
MORNING. HOWEVER MUCH OF THE MOISTURE WILL REMAIN BELOW THE
DENDRITIC GROWTH ZONE SO THE PREDOMINANT PRECIPITATION TYPE SHOULD
BE FREEZING RAIN. PRECIPITATION AMOUNTS SHOULD NOT BE TOO HIGH.
THE...RELATIVELY SPEAKING...HEAVIEST PERIOD OF PRECIPITATION WILL
BE AS THE UPPER DISTURBANCE MOVES THROUGH MID MORNING INTO THE
AFTERNOON HOURS TOMORROW...AND EVEN THEN MODELS ARE SHOWING LESS
THAN A QUARTER OF AN INCH OF QPF IN THE HEAVIEST SPOTS. ONCE THE
DISTURBANCE PASSES THERE SHOULD STILL BE ENOUGH MOISTURE LEFTOVER
FOR SOME LINGERING FREEZING DRIZZLE THROUGH LATE MON EVENING.
PRECIPITATION SHOULD BEGIN WINDING DOWN...AND TEMPERATURES STILL
WARM ENOUGH...TO CONFINE ANY WINTRY PRECIPITATION TO MAINLY THE
NORTHERN TWO ROWS OF COUNTIES.
GIVEN THE CURRENT UNSEASONABLY WARM AIR TEMPERATURES AND THE
RESULT THIS HAS HAD ON GROUND TEMPS...DO NOT EXPECT THERE TO BE
AN IMMEDIATE ACCRUAL OF ICE ON ANY SURFACE ONCE THE FRONT PASSES
AND TEMPERATURES FALL BELOW THE FREEZING MARK IN ANY GIVEN
LOCATION. HOWEVER WITH TEMPS REMAINING BELOW FREEZING...AREAS IN
NRN ARKANSAS WILL UNDOUBTEDLY BEGIN TO SEE ACCUMULATING ICE BEFORE
MIDDAY MON. THIS IS MOST LIKELY TO OCCUR ON ELEVATED SURFACES LIKE
TREES AND POWERLINES...BUT BY MON EVENING ROADWAYS WILL LIKELY BE
COLD ENOUGH SUCH THAT ANY FURTHER FREEZING DRIZZLE OR LIGHT
FREEZING RAIN COULD CAUSE SOME SLICK SPOTS AND HAZARDOUS TRAVEL.
FOR THESE REASONS...HAVE HOISTED UP A WINTER WEATHER ADVISORY IN
THE NRN TWO ROWS OF COUNTIES TO ACCOUNT FOR THIS. FEEL
THAT...DESPITE LACK OF SIGNIFICANT ICE ACCUMULATION...THERE WILL
STILL BE ENOUGH TRAVEL IMPACTS TO WARRANT AN ADVISORY.
ELSEWHERE...CENTRAL AND SOUTHERN ARKANSAS SHOULD NOT SEE
COLD ENOUGH TEMPERATURES WHILE PRECIP IS ONGOING TO WARRANT ANY
CONCERNS AT THIS TIME. OTHERWISE...COOLER THAN NORMAL TEMPERATURES WILL
AFFECT THE STATE THROUGH TUESDAY. BUT A WARMUP IS EXPECTED AS WE
HEAD INTO WED. THE FRONT MOVING THROUGH TOMORROW WILL LIFT BACK
NORTH INTO ARKANSAS ON WED...AND A SIMILAR SITUATION IN TERMS OF
WIDESPREAD LIGHT PRECIPITATION SHOULD DEVELOP WED NIGHT. THIS TIME
ONLY RAIN IS EXPECTED THOUGH AS THERE WILL BE NO ARCTIC BOUNDARY
PUSHING INTO THE REGION FROM THE NORTH TO CHANGE PRECIPITATION OVER.
LONG TERM...THURSDAY THROUGH SUNDAY
AN UNSETTLED WEATHER PATTERN WILL BE OVER THE CENTRAL U.S. AND KEEP
RAIN CHANCES IN THE FORECAST EVERY DAY. THE NEARLY ZONAL UPPER
PATTER WILL KEEP TEMPS WELL ABOVE FREEZING IN NORMAL VALUES...AND
ALLOW SHORT WAVE ENERGY TO MOVE THROUGH THE PATTERN AND AFFECT AR.
THURSDAY WILL START WITH A WEAK FRONTAL BOUNDARY NEARLY STATIONARY
OVER AR...WITH MAINLY A SHOWER POTENTIAL FOR THURSDAY AND FRIDAY. A
BIT MORE SHORT WAVE ENERGY IS SEEN IN THE MODELS FRIDAY AND OVER THE
WEEKEND...SO A BIT BETTER RAIN CHANCES WITH SLIGHT CHANCES OF
THUNDER ARE IN THE FORECAST OVER THE WEEKEND.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST MONDAY FOR BAXTER-
BOONE-FULTON-IZARD-MARION-NEWTON-SEARCY-SHARP-STONE.
&&
$$
AVIATION...51
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
855 PM MST TUE DEC 2 2014
.UPDATE...
ISSUED AT 855 PM MST TUE DEC 2 2014
NO CHANGES TO THE FORECAST NECESSARY AT THIS TIME. HIGH LEVEL
MOISTURE CONTINUES STREAMING OVER THE STATE FROM THE SOUTHWEST
WHICH COULD BECOME DEEP ENOUGH BY TOMORROW AFTERNOON TO PRODUCE
SOME SNOW IN THE MOUNTAINS. A WEAK SURFACE COLD FRONT HAS MOVED
ACROSS THE PLAINS THIS EVENING...BUT WITH LITTLE IMPACT OTHER THAN
COOLING DOWN TEMPERATURES. TEMPERATURE-TO-DEW POINT SPREADS REMAIN
LARGE...SO NO LOW CLOUDINESS IS EXPECTED...ESPECIALLY AS THE HIGH
LEVEL CLOUD COVER CONTINUES TO INCREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 222 PM MST TUE DEC 2 2014
BIG RECOVERY TODAY WITH VERY MILD TEMPERATURES THAT WARMED EVEN
MORE THAN ANTICIPATED WITH A SOMEWHAT DELAYED ARRIVAL OF
CLOUDINESS FROM THE APPROACHING SYSTEM NOW HITTING THE WEST COAST.
WINDS HAVE BEEN INTERESTING WITH DIA STAYING RATHER QUIET WHILE
WESTERLIES PREVAILED ACROSS MUCH OF THE PLAINS...LOOKS LIKE A LEE
SIDE CYCLONE DEVELOPED RIGHT OVER THE AIRPORT. TOMORROW WILL BE
MUCH COOLER AGAIN AS ANOTHER AREA OF HIGH PRESSURE MOVES SOUTHWARD
TO OUR EAST WITH THE OVERALL TROUGH OVER THE MIDDLE CONUS. AN
INITIAL SURGE OF COOLER AIR HAS ALREADY MOVED INTO THE NORTHEAST
CORNER OF THE STATE AND THIS WILL BE FOLLOWED BY A REENFORCEMENT
OF COLDER AIR TONIGHT AS THE MAIN HIGH PUSHES SOUTHEASTWARD. MAIN
QUESTION FOR LATER TONIGHT INTO SUNRISE HOURS IS IF THE LOWER
LEVELS WILL BE MOIST ENOUGH FOR AREAS OF FOG AND LOWER CEILINGS.
SOMEWHAT OF A MIXED MESSAGE FROM THE MODELS...LATEST RAP AND HRRR
RUNS DO NOT SHOW ANY LOWER CLOUDS OR FOG WHILE GOESR PROVING
GROUND SYNTHETIC IMAGERY KEEPS THE LOWER CLOUD FARTHER NORTH. SREF
PROBABILITIES THOUGH ARE IN THE MID RANGE. FOR NOW HAVE KEPT FOG
OUT OF THE GRIDS BUT SOMETHING TO KEEP AN EYE ON FOR THE NEXT
SHIFT.
FOR TOMORROW WITH THE HIGH PRESSURE SLIDING WELL OFF TO OUR EAST
THE FLOW WILL QUICKLY TURN AROUND TO SOUTHERLY ON THE PLAINS AND
SHOULD SET UP A NICE DENVER CYCLONE. THIS COULD KEEP ANY LOWER CLOUDINESS
IN LONGER FROM BOULDER THROUGH DENVER COUNTIES...OTHERWISE DO
EXPECT A GENERALLY MOSTLY CLOUDY DAY ON THE PLAINS WITH LOTS OF
MID LEVEL CLOUDS FROM THE CALIFORNIA SYSTEM. THAT SYSTEM WEAKENS
RAPIDLY AS IT MOVES EASTWARD TONIGHT AND TOMORROW AND NOT
EXPECTING ANY PRECIPITATION TO MAKE IT ONTO THE PLAINS. IN THE
MOUNTAINS HAVE DELAYED THE START OF ANY SNOW A BIT OVERNIGHT THEN
GRADUALLY INCREASING CHANCES TOMORROW FOR A 1 TO 4 INCH TYPE
SNOW...MAYBE MORE IN SOME AREAS BUT OVERALL NOT A GREAT FLOW
PATTERN AND NOT VERY UNSTABLE EITHER SO AT LEAST THROUGH TOMORROW
NOT A LOT OF SNOW ANTICIPATED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 222 PM MST TUE DEC 2 2014
A WEAK DISTURBANCE WILL MOVE ACROSS COLORADO WEDNESDAY NIGHT WITH
A PERIOD OF SNOW WEDNESDAY EVENING OVER THE MOUNTAINS. SNOW WILL
DECREASING LATER IN THE NIGHT AS MOISTURE DEPTH BECOMES MORE
SHALLOW. EXPECT SNOWFALL AMOUNTS TO BE ON THE LIGHT SIDE WITH ONLY
MARGINAL LAPSE RATES. EXPECT HIGHER SNOWFALL AMOUNTS WILL EFFECT
ZONE 31 AND HIGHER AREAS OF ZONE 33.
THE FLOW ALOFT WILL BE MAINLY WESTERLY ON THURSDAY WHILE A SMALL
RIPPLE MOVES THROUGH THE FLOW ON THURSDAY NIGHT. OVERALL MOISTURE
DEPTH WILL REMAIN SHALLOW BUT A BRIEF BUMP UP ON POPS THURSDAY
NIGHT.
THE RIDGE ALOFT BUILDS INTO THE REGION FRIDAY NIGHT WITH MORE
DRYING IN THE MOUNTAINS BUT THIS WILL BE SHORT LIVED. THE NEXT
TROF WILL MOVE ACROSS THE REGION ON LATE SATURDAY AND SUNDAY. MUCH
OF THE ENERGY AND MOISTURE WILL OVER SOUTHERN COLORADO SO ONLY LOW
POPS NEEDED IN THE MOUNTAINS FOR NOW.
ACROSS LOWER ELEVATIONS...CONDITIONS WILL REMAIN DRY AND WARMER
FOR THURSDAY AND FRIDAY. MAYBE ONLY SLIGHT COOLING ON SUNDAY
FOLLOWING A WEAK COLD FRONT. DRY AND WARMER AGAIN FOR MONDAY AND
TUESDAY AS THE RIDGE ALOFT BUILDS INTO COLORADO.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z WEDNESDAY EVENING)
ISSUED AT 855 PM MST TUE DEC 2 2014
HAVE REMOVED THE MENTION OF FOG FROM THE TAFS WITH THE LATEST
AMENDMENTS. CROSS SECTIONS FROM THE EVENING MODEL RUNS SHOW THAT
LOW LEVEL MOISTURE WILL BE LIMITED WITH THE WEAK FRONT THAT HAS
PASSED THROUGH. WITH THE HIGH CLOUDS MOVING OVERHEAD THROUGH THE
NIGHT...IT IS GOING TO BE HARD FOR RADIATIONAL STRATUS TO FORM.
ALSO...WINDS ARE NOW SWITCHING TO SOUTHEASTERLY...WHICH WILL WORK
AGAINST LOW CLOUDS DEVELOPING. WITHOUT ANY LOW CLOUDS OR FOG...NO
AVIATION IMPACTS ARE EXPECTED THROUGH THE NEXT 24 HOURS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DANKERS
SHORT TERM...SZOKE
LONG TERM...ENTREKIN
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
638 PM EST TUE DEC 2 2014
.SYNOPSIS...
A WARM FRONT WILL BRING A WINTRY MIX OF PRECIPITATION
TONIGHT...CHANGING TO ALL RAIN LATE TONIGHT. MUCH MILDER WEATHER
BRIEFLY RETURNS WEDNESDAY. THURSDAY BEGINS A TREND TOWARDS COLDER
BUT DRY CONDITIONS LASTING INTO FRIDAY. LOW PRESSURE MAY BRING A
PERIOD OF RAIN SOMETIME THIS WEEKEND WITH A POSSIBLE WINTRY MIX
ACROSS THE INTERIOR.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
*** WINTRY PRECIPITATION TO IMPACT PRIMARILY INTERIOR SOUTHERN
NEW ENGLAND TONIGHT...
700 PM UPDATE...
OVERALL FORECAST REMAINS ON TRACK FOR THIS EVENING. MADE SOME
MINOR UPDATES TO ACCOUNT FOR CURRENT TRENDS. PRECIP IS STARTING TO
OVERSPREAD SOUTH OF THE MASS PIKE OVER THE PAST HOUR OR TWO.
ANTICIPATE THIS NORTHWARD SPREAD TOWARDS NH WITHIN THE HOUR. MANY
SITES HAVE STARTED OUT AS SNOW...AND ALONG THE SOUTH COAST THEY
HAVE SWITCHED TO A MORE SLEET/SNOW/RAIN MIX. THIS IS DUE TO THE
ADVANCEMENT OF THE WARM LAYER BETWEEN 800-850MB PER RAP DATA.
THIS WARM LAYER WILL CONTINUE TO ADVANCE NORTHWARD FAIRLY
QUICKLY...AND WITH TEMPS STILL NEAR FREEZING EXPECT SLEET/FREEZING
RAIN TO MIX IN. RIGHT NOW DUAL-POL ZDR AND CC SHOW US THE MIXING
LINE IS ACROSS THE UPPER CAPE THROUGH PROVIDENCE AND INTO CENTRAL
CT. EXPECT THIS LINE TO CONTINUE TO ADVANCE NORTHWARD AS THE WARM
AIR ALOFT MOVES IN. ONLY ISSUE TO WATCH IS THE CT RIVER VALLEY
WHICH CURRENTLY HAS NORTHERLY WINDS. THESE WINDS WILL ALLOW FOR
THE SHALLOW COOL AIR TO FUNNEL DOWN KEEPING THE SURFACE TEMPS NEAR
FREEZING...AND ONE OF THE BETTER SPOTS TO SEE SLEET/FREEZING RAIN.
NO CHANGES TO THE HEADLINES FOR NOW AS THE EVENT IS JUST STARTING.
PREVIOUS DISCUSSION...
PRECIP BEGINS AS SNOW IN THE INTERIOR WITH A BRIEF RAIN/SNOW/SLEET
MIX ALONG THE COAST BEFORE BECOMING ALL RAIN. TEMPS NEAR 40 ALONG
THE COAST SHOULD WET BULB DOWN INTO MID 30S AND WITH LOW LEVEL
COLD AIR STILL PRESENT IN THE COLUMN A BRIEF PERIOD OF MIXED
PRECIP APPEARS LIKELY.
WARMING IN THE 850-800 MB LAYER ADVANCES NORTHWARD ACROSS SNE
FAIRLY RAPIDLY THIS EVENING WHICH WILL LIMIT DURATION OF SNOW AND
REDUCE SNOW ACCUM. INTERIOR SNOW CHANGES TO SLEET/FZRA/RAIN WITH
CHANGEOVER MOVING N OF S NH ZONES AROUND 06Z. MAX SNOW WILL BE
NORTH OF ROUTE 2 INTO S NH WHERE AN INCH OR 2 IS POSSIBLE.
ELSEWHERE IN THE INTERIOR OUTSIDE OF 128/495 CORRIDORS LOOKING AN
MAINLY LESS THAN AN INCH. THE MAIN CONCERN TONIGHT IS FOR FREEZING
RAIN IN THE INTERIOR WHERE LOW LEVEL COLD AIR WILL BE SLOW TO
ERODE. FORTUNATELY THIS WILL NOT BE A SIGNIFICANT QPF EVENT WHICH
WILL ONLY RESULT IN LIGHT ACCUM OF ICE. GENERALLY FOLLOWED HIRES
TEMP GUIDANCE WHICH HANGS ON TO NEAR FREEZING TEMPS ACROSS
INTERIOR HIGH TERRAIN AND PORTIONS OF CT VALLEY UNTIL 06-09Z
BEFORE GRADUAL WARMING OCCURS. WITH WEAK SFC WAVE TRACKING ACROSS
E NEW ENG THIS WILL HELP TO LOCK IN A NORTHERLY WIND IN THE
INTERIOR AND CT VALLEY AND HOLD THE LOW LEVEL COLD AIR THROUGH THE
EARLY MORNING. AS A RESULT WE EXPANDED THE WINTER WEATHER ADVISORY
EASTWARD TO BDL-ORH-MHT.
TEMPS WILL HOLD MOSTLY IN THE 30S IN THE INTERIOR...BUT A SURGE
OF MILDER AIR WILL MOVE INTO THE COASTAL PLAIN TOWARD DAYBREAK AS
WINDS SHIFT TO S/SW WITH TEMPS POSSIBLY SPIKING INTO THE 50S
PORTIONS OF RI AND SE MA. GUSTY SE WINDS EXPECTED CAPE/ISLANDS.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
WEDNESDAY...
STEADIER RAIN WILL BE LIFTING TO THE NORTH WED MORNING AS SOME
MID LEVEL DRYING MOVES IN. TEMPS BY 12Z WED SHOULD BE ABOVE
FREEZING IN THE INTERIOR SO NOT LOOKING AT ANY ICE PROBLEMS. LOW
CLOUDS AND AREAS OF DRIZZLE EXPECTED AS DRYING OCCURS IN THE ICE
GROWTH REGION...BUT ADDITIONAL SHOWERS POSSIBLE IN THE AFTERNOON
AS 500-300 MB QG FORCING INCREASES ASSOCD WITH APPROACHING MID
LEVEL SHORTWAVE FROM THE GT LAKES. IT WILL BE A MILD DAY WITH
TEMPS REACHING MID/UPPER 40S NW HIGHER TERRAIN AND MID TO PERHAPS
UPPER 50S COASTAL PLAIN. GUSTY SW WINDS DEVELOP IN THE COASTAL
PLAIN WITH GUSTS TO 30-35 MPH POSSIBLE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* DRY BUT BELOW AVERAGE TEMPS FOR THURS AND FRIDAY
* UNSETTLED WEATHER BRINGING RAIN/WINTRY MIX OVER THE WEEKEND
* LOW CONFIDENCE COASTAL SYSTEM SUNDAY INTO TUESDAY
OVERVIEW...
THE LATEST MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND
ACTIVE LARGER SCALE FLOW PATTERN EVOLUTION OVER MUCH OF THE NEXT
WEEK. HOWEVER...SEVERAL MESOSCALE FEATURES MOVING THROUGH THE FLOW
OFFER A LOW CONFIDENCE FOR BOTH TIMING AND AMPLITUDE. THE TIMING OF
THESE FEATURES AND POTENTIAL ASPECTS OF ANY STREAM PHASING REMAIN
MORE UNCERTAIN. TELECONNECTIONS ALSO SHOW A STORY WITH A -PNA AND A
+NAO...LEADING TO BUILDING HEIGHTS OVER THE NORTHEAST AS WELL AS A
PROGRESSIVE PATTERN DUE TO LACK OF BLOCKING. PNA WILL TURN POSITIVE
YIELDING TO RIDGE OUT WEST AND TROUGH TO THE EAST...FOR LATE WEEKEND
INTO NEXT WEEK. FOR THIS FORECAST PREFER AN ENSEMBLE MEAN BASED
SOLUTION TO FACTOR IN THIS UNCERTAINTY.
DETAILS...
WEDNESDAY NIGHT...HIGH CONFIDENCE.
CONDITIONS WILL BE IMPROVING AS COLD FRONT SWEEPS ACROSS THE REGION.
MAY SEE A FEW SCT SHOWERS BUT OTHERWISE ANTICIPATE A DRY NIGHT.
TEMPS WILL BE DROPPING BEHIND THE FRONT WITH LOWS IN THE MID 20S TO
UPPER 30S. NW WINDS BEHIND THE FRONT WILL REMAIN GUSTY WHICH WILL
LIMIT TEMPS FROM PLUMMETING.
THURSDAY INTO FRIDAY....HIGH CONFIDENCE.
HIGH PRESSURE WILL SWING OVERHEARD WEDNESDAY NIGHT INTO THURSDAY AND
BUILD OVER THE REGION ON FRIDAY. THIS WILL ALLOW FOR DRY WEATHER FOR
THE END OF THE WORK WEEK. 850MB TEMPS WILL DROP BETWEEN -3 TO -12C
ON THURSDAY BUT WARM UP TO ABOUT -2C ON FRIDAY...WHICH WILL YIELD TO
BELOW AVERAGE TEMPS. HIGHS ARE EXPECT TO WARM TO THE LOW TO UPPER
30S ACROSS SOUTHERN NEW ENGLAND. TEMPS THURSDAY NIGHT INTO FRIDAY
MORNING WILL BE THE COOLEST OF THE WEAK AS WINDS DECOUPLE WITH HIGH
PRESSURE OVERHEAD...ANTICIPATE RADIATIONAL COOLING DROPPING TEMPS
DOWN TO THE MID TEENS TO LOW 20S. WEAK WARM AIR ADVECTION WILL BEGIN
LATE FRIDAY INTO SATURDAY ALLOWING FOR TEMPS TO WARM UP OVERNIGHT.
FRIDAY NIGHT INTO SATURDAY...LOW CONFIDENCE.
WEAK DISTURBANCES WILL BE MOVING THROUGH THE FLOW FRIDAY INTO
SATURDAY WHICH WILL SPARK OFF SOME PRECIPITATION ACROSS THE REGION
DURING THIS TIMEFRAME. ANTICIPATE COASTAL REGIONS TO REMAIN ALL RAIN
DURING THIS EVENT...WITH WINTRY PRECIP ACROSS THE INTERIOR. IN FACT
APPEARS THAT A PERIOD OF SLEET OR FREEZING RAIN IS POSSIBLE AS THE
HIGH TO THE NORTH COULD ALLOW FOR COLD AIR DRAINAGE ACROSS THE AREA
ALLOWING FOR TEMPS TO BE BELOW 32F. THIS COMBINED WITH THE WAA THAT
WILL BE MOVING THROUGH THE FLOW WILL YIELD FOR ANOTHER ICING
SITUATION FRI NIGHT/SATURDAY MORNING WITH P-TYPE TRANSITIONING TO
ALL RAIN BY SAT AFTERNOON.
SUNDAY INTO MONDAY...LOW CONFIDENCE.
MODELS BEGIN TO DIVERGE DURING THIS TIME PERIOD ALLOWING FOR THE EC
TO BE MORE AMPLIFIED COMPARED TO THE GFS. REGARDLESS LOOKS LIKE A
SYSTEM WILL BE APPROACHING THE REGION SOMETIME ON SUNDAY THROUGH
TUESDAY...WITH GFS BEING 24 HRS FASTER. RIGHT NOW BELIEVE THAT THIS
WILL BE THE WETTEST TIME DURING THE PERIOD AS THE SRN STREAM UPPER
LOW APPROACHES...INITIATING WEAK SFC CYCLOGENESIS ALONG THE SOUTHERN
MID ATLANTIC COAST. THIS COULD INCREASE LOW LEVEL CONVERGENCE/LIFT
OF MARITIME AIR AS IT APPROACHES THE COAST. ACROSS THE INTERIOR
STILL COULD SEE A WINTRY MIX AS ANOTHER HIGH OVER EASTERN CANADA
COULD PUSH COLD AIR DOWN ACROSS SOUTHERN NEW ENGLAND WITH RAIN ALONG
THE COAST. THIS WEAK SRF LOW COULD EVENTUALLY DEVELOP INTO A COASTAL
LOW AS SOME OF THE GUIDANCE SUGGESTS. BECAUSE OF ALL OF THE
UNCERTAINTY AND THE FACT THAT THIS SYSTEM IS STILL 5+ DAYS AWAY WILL
NEED TO CONTINUE TO MONITOR THIS SYSTEM IN THE COMING DAYS.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /THROUGH TUESDAY NIGHT/...
TONIGHT...OVERALL HIGH CONFIDENCE BUT LOWER CONFIDENCE ON TIMING
OF PRECIP TRANSITION. WIDESPREAD MVFR/IFR CONDITIONS AS WINTRY MIX
EXPANDS NORTH ACROSS SNE. PTYPE MAINLY RAIN S COAST TERMINALS WITH
SNOW TRANSITIONING TO PL/FZRA THEN RA INTERIOR. MINOR SNOW/ICE
ACCUMULATIONS LIKELY INTERIOR. ALL INTERIOR LOCATIONS SHOULD BE
ABOVE FREEZING BY 12Z WITH RAIN DOMINANT PTYPE. SE WIND GUSTS TO
25 KT DEVELOPING OVERNIGHT ON CAPE/ISLANDS.
WEDNESDAY...MODERATE CONFIDENCE. A MIX OF MVFR/IFR CONDITIONS
LIKELY. STEADY RAIN LIFTS TO THE NORTH IN THE MORNING BUT AREAS
OF DRIZZLE AND PATCHY FOG LIKELY. GUSTY SW WINDS DEVELOPING IN
THE COASTAL PLAIN WITH G25-30 KT LIKELY.
KBOS TERMINAL...MODERATE CONFIDENCE IN PRECIPITATION TIMING AND
TYPE. A BRIEF PERIOD OF SNOW OR SLEET POSSIBLE THIS EVENING AT
ONSET. NO FZRA EXPECTED.
KBDL TERMINAL...MODERATE CONFIDENCE IN PRECIPITATION TIMING AND
TYPE. SNOW/SLEET AT ONSET WITH A BRIEF PERIOD OF FZRA LIKELY THIS
EVENING BEFORE CHANGING TO ALL RAIN.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
WEDNESDAY NIGHT...HIGH CONFIDENCE. ANY LINGERING MVFR CONDITIONS
WILL QUICKLY IMPROVE TO VFR.
THURSDAY...HIGH CONFIDENCE. VFR.
FRIDAY INTO SATURDAY...MODERATE CONFIDENCE. MVFR/IFR CIGS WILL
INCREASE IN THE EVENING. RAIN SHOWERS SE AND POSSIBLE WINTRY MIX NW
EARLY SATURDAY MORNING WILL SLOWLY IMPROVE AFTER COLD FRONT MOVES
THROUGH REGION ON SATURDAY.
SUNDAY...LOW CONFIDENCE. MVFR CIGS WILL CONTINUE WITH ANOTHER ROUND
OF WINTRY MIX POSSIBLE ACROSS THE INTERIOR AND RAIN ACROSS THE
COAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /THROUGH WEDNESDAY/...MODERATE CONFIDENCE.
SCA HEADLINES EXPANDED TO ALL WATERS. EASTERLY WIND GUSTS TO 25
KT WILL VEER TO SE TONIGHT AND BECOME SW WED MORNING. SW LOW LEVEL
JET 40-50 KT DEVELOPS DURING WED AFTERNOON BUT NOT CONFIDENT HOW
MUCH OF THIS WIND WILL MIX DOWN. WE ARE FAIRLY CONFIDENT IN SCA
GUSTS TO 30 KT WITH LOW PROB OF REACHING GALE FORCE GUSTS. NO
GALE HEADLINES YET DUE TO UNCERTAINTY BUT THIS WILL BE RE-
EVALUATED IN FUTURE FORECASTS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
WEDNESDAY NIGHT...SMALL CRAFT ADVISORIES NECESSARY DUE TO GUSTY
WINDS WHICH WILL BE SLOWLY RELAXING OVERNIGHT.
THURSDAY AND FRIDAY...WINDS AND SEAS WILL BOTH RELAX AND DROP BELOW
SMALL CRAFT CRITERIA AS HIGH PRESSURE CRESTS OVER THE WATERS.
SATURDAY INTO SUNDAY...WINDS AND SEAS SLOWLY BUILD AS A COLD FRONT
APPROACHES THE WATERS AND WEAK SURFACE LOW PRESSURE DEVELOPS OVER
THE MID-ATLANTIC.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 6 AM EST WEDNESDAY FOR CTZ002.
MA...WINTER WEATHER ADVISORY UNTIL 6 AM EST WEDNESDAY FOR
MAZ002>004-008>011-026.
NH...WINTER WEATHER ADVISORY UNTIL 8 AM EST WEDNESDAY FOR NHZ011-
012-015.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EST THURSDAY FOR ANZ231>235-
237-251.
SMALL CRAFT ADVISORY UNTIL 1 AM EST THURSDAY FOR ANZ230-236.
SMALL CRAFT ADVISORY UNTIL 5 AM EST THURSDAY FOR ANZ250-
254>256.
&&
$$
SYNOPSIS...KJC/DUNTEN
NEAR TERM...KJC/DUNTEN
SHORT TERM...KJC
LONG TERM...DUNTEN
AVIATION...KJC/DUNTEN
MARINE...KJC/DUNTEN
AREA FORECAST DISCUSSION
NWS NEW YORK NY
356 PM EST MON DEC 1 2014
.SYNOPSIS...
WEAK LOW PRESSURE OFF THE CAROLINA COAST ON TUESDAY MOVES NORTH
ACROSS THE REGION LATE TUESDAY NIGHT. ANOTHER COLD FRONT PASSES
WEDNESDAY AFTERNOON WITH STRONG HIGH PRESSURE BUILDING IN FOR
THURSDAY. A STATIONARY FRONTAL BOUNDARY WILL THEN SET UP OVER THE
AREA FRIDAY THRU THE WEEKEND.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
THE COLD FRONT IS NOW PASSING ACROSS EASTERN LONG ISLAND. COLD AIR
STILL WELL BEHIND THE FRONT. HRRR HAS GONE BAD WITH THE PCPN OVER
CENTRAL PA. BASED ON EXTRAPOLATION, EXPECT THIS LIGHT PCPN IN NYC
AROUND 6 PM. THE PCPN IS MOVING QUICKLY...THUS STILL EXPECTING IT
OUT OF THE REGION BEFORE MIDNIGHT.
LIFT COMES FROM JET DYNAMICS OF THE 140+ KT JET`S RIGHT REAR
ENTRANCE REGION. PCPN IS JUST A FEW HUNDREDS.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH TUESDAY NIGHT/...
HIGH PRESSURE PASSES EAST ACROSS QUEBEC OVERNIGHT INTO TOMORROW
MORNING WHICH QUICKLY VEERS WINDS TO EAST AS WEAK LOW PRESSURE
FORMS OFF THE COAST OF NORFOLK. ALL NWP APPEARS CONSISTENT WITH
LIGHT PCPN MOVING IN BEFORE SUNSET.
THERMAL PROFILES SUPPORT A BRIEF MIX AT THE START FOR THE COAST
WITH SNOW INLAND. THE SOUTHEAST VEERING FLOW QUICKLY WARMS TEMPS
ALOFT RESULTING IN A WINTRY MIX INLAND AS WELL BY 8 PM OR SO. THE
PROBLEM IS THAT THE COLD AIR WILL LIKELY HOLD AT THE SURFACE UNTIL
MIDNIGHT OR FEW HOURS AFTER SUCH THAT FREEZING RAIN BECOMES A
TRAVEL PROBLEM. WE DO EXPECT THE VAST MAJORITY OF THE INTERIOR TO
BE ABOVE FREEZING BY SUNRISE.
A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED FOR THE INTERIOR.
BASED ON COLLABORATION WITH SURROUNDING NWS OFFICES...WE`LL ISSUE
THESE ON THE MIDNIGHT SHIFT (ASSUMING THE FORECAST DOES NOT
CHANGE).
ACCUMULATION OF SNOW OVER THE INTERIOR IS LESS THAN AN INCH AND
PROBABILISTIC SNOW DATA HAS BEEN ISSUED. ICE ACCUMULATION OF LESS
THAN A TENTH OF AN INCH OR LESS IS FORECAST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE UPR JET WILL ALLOW FOR GENERALLY ZONAL FLOW ALOFT THRU THE LONG
TERM.
ON WED...THE CWA WILL ENTER THE WARM SECTOR BRIEFLY AS A WRMFNT
LIFTS TO THE N. THIS WILL CUT OFF THE STEADY RAIN...BUT ALLOW FOR
SOME POCKETS OF LIGHT RAIN AND DZ TO DEVELOP. SOME PATCHY FG WILL
ALSO BE POSSIBLE. TEMPS ABOUT 5 DEGREES ABV NORMAL.
THE CDFNT COMES THRU WED NGT. THIS USHERS THE HIGHER HUMIDITY
OFFSHORE...AND CLEARS OUT THE SKIES FOR THU. TEMPS ON THU BLW CLIMO
BY A FEW DEGREES.
THE CWA IS THEN IN THE BATTLE ZONE BETWEEN THE DEPARTING 1040S HI
OVER ERN CANADA...AND SWLY FLOW ALOFT PRODUCING SOME WAA AND WEAK
MOISTURE TRANSPORT. THIS WILL KEEP IT MAINLY CLOUDY FRI THRU THE
WEEKEND...WITH PERIODS OF PCPN.
ALL AREAS SUSCEPTIBLE TO SNOW OR A WINTRY MIX TO START OUT THE PCPN
FRI...THEN THE COASTS AND CITY APPEAR TO TRANSITION TO MAINLY ALL
RAIN FOR THE REMAINDER OF THE PERIOD. THE INTERIOR WILL STRUGGLE
BOTH TO WARM INITIALLY...AND THEREAFTER STAY ABV FREEZING. AS A
RESULT...A WINTRY MIX HAS BEEN INCLUDED IN THE FCST THRU THE
WEEKEND.
THE UNSETTLED PATTERN MAY END WITH WEAK LOW PRES DEVELOPING AND THEN
FINALLY TRACKING OUT TO SEA. THE ROUGH TIMING FOR THIS IS
MON...ALTHOUGH IT IS TOO FAR OUT TO PIN DOWN ATTM. THIS SCENARIO
WOULD RESULT IN MORE RAIN AT THE COASTS AND A MIX AGAIN ACROSS THE
INTERIOR. BECAUSE THIS SETUP WOULD BE MORE CONDUCIVE TO COOLING
ALOFT...THE INTERIOR WOULD RUN THE THREAT FOR A CHANGEOVER TO ALL
SNOW WITH SOME ACCUMS.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
COLD FRONT CONTINUES TO WORK ITS WAY ACROSS THE TERMINALS. WINDS
HAVE BEGUN TO SHIFT TO THE NW...AND THAT TREND WILL CONTINUE THROUGH
22Z. WINDS INCREASE TO 10-15 KT WITH 15-20 KT GUSTS DURING THE EARLY
EVENING. GUSTS END BY MIDNIGHT TONIGHT...AND WINDS GRADUALLY
DIMINISH TO 8-12 KT THROUGH THE OVERNIGHT. WINDS CONTINUE TO VEER TO
THE NE...AND EVENTUALLY TO THE E...ON TUESDAY AT 8-12 KT.
MAINLY VFR CONDS...BUT THERE MAY BE SOME BRIEF POCKETS OF MVFR CONDS
IN LIGHT RAIN AS THE FRONT MOVES ACROSS THE REGION. WILL ADD SOME
-RA TO THE TAFS FROM AROUND 23Z-04Z...BUT WILL KEEP CONDS VFR. BEST
CHANCES FOR MVFR CIGS WILL BE AT KSWF.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR
MVFR CONDS IN -RA FROM 23Z-04Z.
KLGA FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR
MVFR CONDS IN -RA FROM 23Z-04Z.
KEWR FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR
MVFR CONDS IN -RA FROM 23Z-04Z.
KTEB FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR
MVFR CONDS IN -RA FROM 23Z-04Z.
KHPN FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR
MVFR CONDS IN -RA FROM 23Z-04Z.
KISP FCSTER COMMENTS: ANY GUSTS MAY END PRIOR TO 05Z. LOW CHANCE FOR
MVFR CONDS IN -RA FROM 00Z-05Z.
.OUTLOOK FOR 21Z TUESDAY THROUGH SATURDAY...
.TUESDAY...MVFR OR LOW CONDS POSSIBLE LATE AFTERNOON IN -RASN.
.TUESDAY NIGHT...WINTRY MIX. RASN ALONG COAST CHANGES TO RAIN
EARLY IN THE EVENING. ACROSS INTERIOR...CHANGEOVER WILL BE
SLOWER...AS SN MIXES WITH SLEET/FREEZING RAIN BEFORE CHANGING TO
FREEZING RAIN.
.WEDNESDAY...SUB-VFR POSSIBLE IN -RA/DZ/FG IN THE MORNING.
IMPROVING CONDS LATE.
.THURSDAY...VFR.
.FRIDAY...LIGHT RAIN AND/OR SNOW POSSIBLE IN THE AFTERNOON.
.FRIDAY NIGHT...CHANCE FOR RAIN ALONG THE COAST AND
SNOW/SLEET/FREEZING RAIN ACROSS INTERIOR.
.SATURDAY...CHANCE FOR RAIN ALONG THE COAST AND
SNOW/SLEET/FREEZING RAIN FOR INTERIOR IN THE MORNING...THEN CHANCE
FOR RAIN IN THE AFTERNOON.
&&
.MARINE...
THE COLD FRONT IS PASSING EAST OF THE WATERS EARLY THIS EVENING.
WINDS INCREASE SUCH THAT ALL WATERS ARE NOW UNDER A SCA DUE TO
STRONG COLD ADVECTION THIS EVENING.
SCA CONDITION REMAIN ON THE WATERS ON TUESDAY AND WILL LIKELY NEED
EXTENDING INTO TUESDAY NIGHT.
WINDS INCREASE AHEAD OF A CDFNT WED. SCA SPEEDS LIKELY...ESPECIALLY
ERN WATERS. THE WINDS SHIFT WITH THE FRONT WED NGT...THEN DECREASE
BLW SCA LVLS THU. WINDS AND SEAS WILL THEN LIKELY REMAIN BLW SCA
LVLS TIL SUN. THEREAFTER...THE POTENTIAL DEVELOPMENT OF LOW PRES MAY
BRING WINDS AND SEAS TO SCA LVLS...PARTICULARLY ON THE OCEAN.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED TODAY THROUGH TUESDAY
MORNING. QPF LATE DAY TUE INTO WED MORNING SHOULD BE ABOUT A THIRD
OF AN INCH. A WINTRY MIX OVER THE INTERIOR IS FORECAST AND NO
HYDROLOGIC IMPACTS ARE EXPECTED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EST
TONIGHT FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...JMC/TONGUE
NEAR TERM...TONGUE
SHORT TERM...TONGUE
LONG TERM...JMC
AVIATION...MPS
MARINE...JMC/TONGUE
HYDROLOGY...TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1252 PM EST MON DEC 1 2014
.SYNOPSIS...
HIGH PRESSURE OVER EASTERN CANADA PUSHES A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. WEAK LOW PRESSURE OFF THE CAROLINA COAST ON
TUESDAY AND MOVES NORTH ACROSS THE REGION LATE TUESDAY NIGHT.
ANOTHER COLD FRONT PASSES WEDNESDAY AFTERNOON WITH STRONG HIGH
PRESSURE BUILDING IN FOR THURSDAY.
A PROLONGED PERIOD OF UNSETTLED WEATHER IS POSSIBLE FROM FRIDAY
THROUGH NEXT WEEKEND.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
CLOUDS CONTINUE TO INCREASE WITH THE COLD FRONT NOW ACROSS ORANGE
COUNTY AND APPROACHING THE NY METRO. TEMPS ARE AT OR NEAR THEIR
MAX AT THE CURRENT TIME WITH LOWER 60S FOR THE NY METRO...LONG
ISLAND AN THE CT RIVER VALLEY.
HRRR, NARRE-TL AND RAP ALL CONTINUE TO SUGGESTING LIGHT RA IS
LIKELY FOR THE EVENING. START TIME IS ABOUT 5 PM IN NYC AND THEN
SPREADS ACROSS LONG ISLAND. POPS WERE RAISED TO 60%.
LIFT COMES FROM JET DYNAMICS OF THE 140+ KT JET`S RIGHT REAR
ENTRANCE REGION. PCPN IS JUST A FEW HUNDREDS.
&&
.SHORT TERM /MIDNIGHT THROUGH 6 PM TUESDAY/...
RAIN ENDS BEFORE MIDNIGHT OVER LONG ISLAND.
UPPER FLOW BECOMES MORE ZONAL TONIGHT INTO TUESDAY...THEN A
SHORTWAVE MOVES THROUGH THE NORTHERN STREAM FLOW TUESDAY
AFTERNOON. AT THE SURFACE HIGH PRESSURE MOVES THROUGH THE GREAT
LAKES AND NEW ENGLAND TONIGHT THROUGH TUESDAY. AGAIN GUIDANCE IS
SIMILAR WITH THE HIGH. WITH THE HIGH TO THE NORTH A STRONG
NORTHEAST TO EAST FLOW DEVELOPS AND COLD AIR DAMMING OCCURS.
TUESDAY AFTERNOON A WAVE OF LOW PRESSURE DEVELOPS OFF THE CAROLINA
COAST ON THE OLD FRONTAL BOUNDARY AS A SOUTHERN STREAM SHORTWAVE
REACHES THE SOUTHEAST. THE LOW THEN MOVES NORTH ALONG THE COAST
INTO THE COLD AIR. WITH THE STRONG HIGH TO THE NORTH THE GFS
ERODES THE COLD AIR TOO QUICKLY...WHILE THE NAM AND ECMWF HOLD ON
TO THE COLD AIR. LEANED TOWARD THE COLDER SOLUTIONS FOR
PRECIPITATION TYPE WITH CHANCE POPS BY LATE TUESDAY.
FOR TEMPERATURES ALSO LEANED TOWARD THE COOLER NAM AND ECS GUIDANCE
FOR LOWS TONIGHT AND HIGHS TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
A WARM FRONT AND ACCOMPANYING WEAK SFC WAVE LIFTING NE ALONG THE
COAST WILL BRING STEADY PCPN TO THE AREA TUE NIGHT. PCPN SHOULD
BEGIN AS SNOW INLAND...THEN QUICKLY TRANSITION OVER TO MIXED PCPN
AND THEN RAIN IN MOST PLACES BY LATE TUE EVENING AS TEMPS WARM
ALOFT. THE EXCEPTION WILL BE WELL INLAND IN PLACES SUCH AS ORANGE...
W PASSAIC...PUTNAM AND N FAIRFIELD COUNTIES...WHERE COLD AIR
DAMMING IN THE WAKE OF A DEPARTING 1045 MB WILL LOCK IN SUB-
FREEZING AIR... WITH SNOW TRANSITIONING TO LIGHT FREEZING RAIN.
THE PCPN EVENT SHOULD BE LIGHT...SO ATTM DO NOT EXPECT MUCH MORE
THAN AN UP TO AN INCH OF LIGHT SNOW INLAND...AND A LIGHT GLAZE OF
ICE IN THE AREAS WHERE FREEZING RAIN DOES OCCUR.
AS THE WARM FRONT LIFTS N WED MORNING...PCPN SHOULD QUICKLY
TRANSITION TO LIGHT RAIN OR DRIZZLE...AND SW FLOW SHOULD BRING IN
MILER AIR...WITH HIGHS IN THE LOWER/MID 50S THROUGHOUT PER WARMEST
MOS GUIDANCE...A FEW DEG ABOVE NORMAL. A COLD FRONT SHOULD QUICKLY
FOLLOW LATE WED AFTERNOON OR WED EVENING...WITH LOW TEMPS IN THE 30S
WED NIGHT. AS AN UPPER TROUGH SWINGS E ACROSS NEW ENGLAND AN ERN
CANADA...INCREASING SFC CONFLUENCE IN ITS WAKE WILL LEAD TO
DEVELOPMENT OF STRONG HIGH PRESSURE OVER THE NRN PLAINS WED NIGHT
THAT BUILDS E-WARD TOWARD THE AREA THU-FRI...WITH BELOW NORMAL
TEMPS.
AS THIS SECOND STRONG HIGH DEPARTS...WILL SEE A SCENARIO SIMILAR TO
THAT OF TUE NIGHT UNFOLD FOR FRI NIGHT-SAT AS ANOTHER FRONTAL SYSTEM
APPROACHES FROM THE SW...WITH WARMING ALOFT AND SFC COLD AIR DAMMING
LEADING TO MIXED PCPN INLAND AND MAINLY RAIN AT THE COAST.
SHOULD THEN SEE AN EXTENDED PD OF UNSETTLED WX...MAINLY RAIN AS A
SLOW MOVING UPPER TROUGH APPROACHES FROM THE WEST.
&&
.AVIATION /17Z MONDAY THROUGH SATURDAY/...
COLD FRONT WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON THROUGH
EARLY EVENING. MAINLY VFR CONDS...BUT THERE MAY BE SOME BRIEF
POCKETS OF MVFR CONDS IN LIGHT RAIN AS THE FRONT MOVES ACROSS THE
REGION. WILL ADD SOME -RA TO THE TAFS FROM AROUND 23Z-04Z...BUT
WILL KEEP CONDS VFR.
S/SW WINDS WILL VEER TO THE W/NW LATE IN THE AFTERNOON...AND THEN
WILL VEER TO THE N/NW TONIGHT. WINDS INCREASE TO 10-15 KT WITH
15-20 KT GUSTS DURING THE LATE AFTERNOON/EARLY EVENING...AND THEN
GUSTS END BY MIDNIGHT TONIGHT...AND WINDS GRADUALLY DIMINISH TO
8-12 KT THROUGH THE OVERNIGHT.
WINDS CONTINUE TO VEER TO THE NE...AND EVENTUALLY TO THE E...ON
TUESDAY AT 8-12 KT.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1
HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA
FROM 23Z-04Z.
KLGA FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1
HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA
FROM 23Z-04Z.
KEWR FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1
HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA
FROM 23Z-04Z.
KTEB FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1
HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA
FROM 23Z-04Z.
KHPN FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1
HOUR. GUSTS MAY END PRIOR TO 04Z. LOW CHANCE FOR MVFR CONDS IN -RA
FROM 23Z-04Z.
KISP FCSTER COMMENTS: TIMING OF WIND SHIFT COULD BE OFF BY +/- 1
HOUR. GUSTS MAY END PRIOR TO 05Z. LOW CHANCE FOR MVFR CONDS IN
-RA FROM 00Z-05Z.
.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...
.TUESDAY...MVFR OR LOW CONDS POSSIBLE LATE AFTERNOON IN -RASN.
.TUESDAY NIGHT...WINTRY MIX. RASN ALONG COAST CHANGES TO RAIN
EARLY IN THE EVENING. ACROSS INTERIOR...CHANGEOVER WILL BE
SLOWER...AS SN MIXES WITH SLEET/FREEZING RAIN BEFORE CHANGING TO
FREEZING RAIN.
.WEDNESDAY...SUB-VFR POSSIBLE IN -RA/DZ/FG IN THE MORNING.
IMPROVING CONDS LATE.
.THURSDAY...VFR.
.FRIDAY...LIGHT RAIN AND/OR SNOW POSSIBLE IN THE AFTERNOON.
.FRIDAY NIGHT...CHANCE FOR RAIN ALONG THE COAST AND
SNOW/SLEET/FREEZING RAIN ACROSS INTERIOR.
.SATURDAY...CHANCE FOR RAIN ALONG THE COAST AND
SNOW/SLEET/FREEZING RAIN FOR INTERIOR IN THE MORNING...THEN CHANCE
FOR RAIN IN THE AFTERNOON.
&&
.MARINE...
NO CHANGES AT THIS TIME...THOUGH WE MAY NEED SCA ALL WATERS THIS
EVENING BEHIND THE COLD FRONT WITH COLD ADVECTION. IT WOULD THOUGH
BE SHORT LIVED.
SEAS ON THE OCEAN WATERS REMAIN AT SMALL CRAFT LEVELS THIS
MORNING IN A SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD FRONT.
THEN WITH A WIND SHIFT TO THE NORTHWEST BEHIND THE FRONT...LATE
THIS AFTERNOON INTO THIS EVENING...AND COLD ADVECTION WIND GUSTS
ON THE OCEAN WATERS WILL BE AT MARGINAL SMALL CRAFT LEVELS. IN
ADDITION SEAS WILL STILL BE AT SMALL CRAFT LEVELS AND SLOWLY
SUBSIDING. SEAS MAY FALL BELOW SMALL CRAFT LATE TONIGHT INTO EARLY
TUESDAY. HOWEVER...WITH A STRONG AND GUSTY NORTHEAST TO EAST FLOW
DEVELOPING TUESDAY AS HIGH PRESSURE MOVES THROUGH NEW ENGLAND AND
A WAVE OF LOW PRESSURE ON THE COLD FRONT BEGINS TO MOVE NORTH WIND
GUSTS WILL AGAIN BE AT SMALL CRAFT LEVELS AND OCEAN SEAS WILL
BUILD. WITH HIGH CONFIDENCE IN SMALL CRAFT CONDITIONS HAVE
EXTENDED THE ADVISORY THROUGH TUESDAY.
EXPECT SCA CONDS ON ALL WATERS TUE NIGHT...WITH MODERATE E FLOW
BETWEEN DEPARTING STRONG HIGH PRESSURE AND AN APPROACHING WARM FRONT
AND ACCOMPANYING WEAK SFC LOW. GUSTS ON THE OCEAN COULD APPROACH
MINIMAL GALE FORCE...ESPECIALLY OUT EAST...AND SEAS COULD BUILDS AS
HIGH AS 9 FT. SCA CONDS SHOULD THEN PERSIST ON THE OCEAN INTO
WED-WED NIGHT AS THE WARM FRONT LIFTS TO THE N AND MODERATE SW FLOW
AHEAD OF A COLD FRONT GUSTS UP TO 25 KT DURING THE DAY ON WED...
FOLLOWED BY LINGERING SEAS ABOVE 5 FT WED NIGHT. GENERALLY QUIET
CONDS EXPECTED FOR THU-FRI AS HIGH PRESSURE BUILDS IN...BUT OCEAN
SEAS COULD APPROACH 5 FT FRI NIGHT AS NE FLOW SOUTH OF THE HIGH
INCREASES.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED TODAY THROUGH TUESDAY
MORNING. QPF WITH THE WARM FRONTAL APPROACH/PASSAGE FROM LATE
DAY TUE INTO WED MORNING SHOULD BE ABOUT 3-4 TENTHS OF AN INCH.
SOME OF THIS SHOULD FALL AS SNOW ACROSS INTERIOR LOCATIONS. NO
HYDROLOGIC IMPACTS ARE EXPECTED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...TONGUE
NEAR TERM...TONGUE
SHORT TERM...TONGUE
LONG TERM...GOODMAN
AVIATION...MPS
MARINE...TONGUE
HYDROLOGY...TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1007 AM EST MON DEC 1 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON FOLLOWED
BY HIGH PRESSURE. A WAVE OF LOW PRESSURE OFF THE CAROLINA COAST
MOVES TOWARD THE AREA TUESDAY AFTERNOON PUSHING A WARM FRONT
TOWARDS THE AREA TUESDAY NIGHT. THE WARM FRONT PASSES TO THE NORTH
ON WEDNESDAY...FOLLOWED BY A COLD FRONTAL PASSAGE WEDNESDAY
EVENING. STRONG HIGH PRESSURE THEN BUILDS IN FOR THURSDAY.
A PROLONGED PERIOD OF UNSETTLED WEATHER IS POSSIBLE FROM FRIDAY
THROUGH NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CHANGES THIS MORNING INCLUDE RAISING TEMPS FOR EASTERN PORTIONS AND
INCREASING POPS FOR THIS EVENING.
TEMPS ARE INTO THE LOWER 60S ON PARTS OF LONG ISLAND AS OF 10 AM.
HAVE UPDATED TEMP FCST TODAY BASED ON LATEST TRENDS AND LAMP
GUIDANCE.
BIGGER CHANGE WAS TO INCREASE POPS FOR LIGHT RAIN MOVING IN THIS
EVENING POST FRONTAL. HRRR, NARRE-TL AND RAP ALL SUGGESTING LIGHT
RA IS LIKELY FOR THE EVENING. START TIME IS ABOUT 5 PM IN NYC AND
THEN SPREADS ACROSS LONG ISLAND.
LIFT COMES FROM JET DYNAMICS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
RAIN ENDS BEFORE MIDNIGHT OVER LONG ISLAND.
UPPER FLOW BECOMES MORE ZONAL TONIGHT INTO TUESDAY...THEN A
SHORTWAVE MOVES THROUGH THE NORTHERN STREAM FLOW TUESDAY
AFTERNOON. AT THE SURFACE HIGH PRESSURE MOVES THROUGH THE GREAT
LAKES AND NEW ENGLAND TONIGHT THROUGH TUESDAY. AGAIN GUIDANCE IS
SIMILAR WITH THE HIGH. WITH THE HIGH TO THE NORTH A STRONG
NORTHEAST TO EAST FLOW DEVELOPS AND COLD AIR DAMMING OCCURS.
TUESDAY AFTERNOON A WAVE OF LOW PRESSURE DEVELOPS OFF THE CAROLINA
COAST ON THE OLD FRONTAL BOUNDARY AS A SOUTHERN STREAM SHORTWAVE
REACHES THE SOUTHEAST. THE LOW THEN MOVES NORTH ALONG THE COAST
INTO THE COLD AIR. WITH THE STRONG HIGH TO THE NORTH THE GFS
ERODES THE COLD AIR TOO QUICKLY...WHILE THE NAM AND ECMWF HOLD ON
TO THE COLD AIR. LEANED TOWARD THE COLDER SOLUTIONS FOR
PRECIPITATION TYPE WITH CHANCE POPS BY LATE TUESDAY.
FOR TEMPERATURES ALSO LEANED TOWARD THE COOLER NAM AND ECS GUIDANCE
FOR LOWS TONIGHT AND HIGHS TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
A WARM FRONT AND ACCOMPANYING WEAK SFC WAVE LIFTING NE ALONG THE
COAST WILL BRING STEADY PCPN TO THE AREA TUE NIGHT. PCPN SHOULD
BEGIN AS SNOW INLAND...THEN QUICKLY TRANSITION OVER TO MIXED PCPN
AND THEN RAIN IN MOST PLACES BY LATE TUE EVENING AS TEMPS WARM
ALOFT. THE EXCEPTION WILL BE WELL INLAND IN PLACES SUCH AS ORANGE...
W PASSAIC...PUTNAM AND N FAIRFIELD COUNTIES...WHERE COLD AIR
DAMMING IN THE WAKE OF A DEPARTING 1045 MB WILL LOCK IN SUB-
FREEZING AIR... WITH SNOW TRANSITIONING TO LIGHT FREEZING RAIN.
THE PCPN EVENT SHOULD BE LIGHT...SO ATTM DO NOT EXPECT MUCH MORE
THAN AN UP TO AN INCH OF LIGHT SNOW INLAND...AND A LIGHT GLAZE OF
ICE IN THE AREAS WHERE FREEZING RAIN DOES OCCUR.
AS THE WARM FRONT LIFTS N WED MORNING...PCPN SHOULD QUICKLY
TRANSITION TO LIGHT RAIN OR DRIZZLE...AND SW FLOW SHOULD BRING IN
MILER AIR...WITH HIGHS IN THE LOWER/MID 50S THROUGHOUT PER WARMEST
MOS GUIDANCE...A FEW DEG ABOVE NORMAL. A COLD FRONT SHOULD QUICKLY
FOLLOW LATE WED AFTERNOON OR WED EVENING...WITH LOW TEMPS IN THE 30S
WED NIGHT. AS AN UPPER TROUGH SWINGS E ACROSS NEW ENGLAND AN ERN
CANADA...INCREASING SFC CONFLUENCE IN ITS WAKE WILL LEAD TO
DEVELOPMENT OF STRONG HIGH PRESSURE OVER THE NRN PLAINS WED NIGHT
THAT BUILDS E-WARD TOWARD THE AREA THU-FRI...WITH BELOW NORMAL
TEMPS.
AS THIS SECOND STRONG HIGH DEPARTS...WILL SEE A SCENARIO SIMILAR TO
THAT OF TUE NIGHT UNFOLD FOR FRI NIGHT-SAT AS ANOTHER FRONTAL SYSTEM
APPROACHES FROM THE SW...WITH WARMING ALOFT AND SFC COLD AIR DAMMING
LEADING TO MIXED PCPN INLAND AND MAINLY RAIN AT THE COAST.
SHOULD THEN SEE AN EXTENDED PD OF UNSETTLED WX...MAINLY RAIN AS A
SLOW MOVING UPPER TROUGH APPROACHES FROM THE WEST.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
NO SIGNIFICANT CHANGES MADE TO THE PREVIOUS TAF PACKAGE.
A COLD FRONT WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON.
MAINLY VFR. THERE IS A LOW POTENTIAL FOR MVFR CIGS WITH A FEW
SHOWERS ACROSS COASTAL TERMINALS IN THE AFTERNOON INTO EARLY EVE AS
THE FRONT MOVES THROUGH AND LINGERING IN ITS WAKE. CONFIDENCE IS TOO
LOW TO INCLUDE IN THE TAFS.
SOUTHWEST WIND OF AROUND 10 KT AHEAD OF THE COLD FRONT AND GUSTY NW
WINDS IN WAKE OF THE COLD FRONT LATE THIS AFTERNOON INTO THE
EVENING. DIMINISHING THREAT FOR MVFR CONDITIONS AND SHOWERS AS
EVENING PROGRESSES.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: CHANCE OF MVFR CIGS THIS AFTERNOON. TIMING OF
WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD
FRONTAL PASSAGE.
KLGA FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO
BASED ON TIMING OF THE COLD FRONTAL PASSAGE.
KEWR FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO
BASED ON TIMING OF THE COLD FRONTAL PASSAGE.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS YELLOW...WHICH IMPLIES
SLANT RANGE VISIBILITY 4-6SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO
BASED ON TIMING OF THE COLD FRONTAL PASSAGE.
KHPN FCSTER COMMENTS: TIMING OF WINDS COULD BE OFF BY AN HOUR OR TWO
BASED ON TIMING OF THE COLD FRONTAL PASSAGE.
KISP FCSTER COMMENTS: CHANCE OF MVFR CIGS THIS AFTERNOON. TIMING OF
WINDS COULD BE OFF BY AN HOUR OR TWO BASED ON TIMING OF THE COLD
FRONTAL PASSAGE.
.OUTLOOK FOR 15Z TUE THROUGH FRI...
.TUE...VFR INTO MID AFTERNOON...THEN A CHANCE OF MVFR CONDITIONS
WITH LIGHT RAIN AND LIGHT SNOW.
.TUE NIGHT...SN TO RA WITH MVFR OR LOWER CONDITIONS LIKELY. SN TO FZRA
AT KSWF.
.WED...CHANCE OF RAIN WITH MVFR OR LOWER CONDITIONS. LOW PROB OF FZRA
AT KSWF IN THE MORNING.
.THU...VFR
.FRI...CHANCE OF LIGHT RAIN AND/OR SNOW IN THE AFTERNOON.
&&
.MARINE...
NO CHANGES AT THIS TIME...THOUGH WE MAY NEED SCA ALL WATERS THIS
EVENING BEHIND THE COLD FRONT WITH COLD ADVECTION.
SEAS ON THE OCEAN WATERS REMAIN AT SMALL CRAFT LEVELS THIS
MORNING IN A SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD FRONT.
THEN WITH A WIND SHIFT TO THE NORTHWEST BEHIND THE FRONT...LATE
THIS AFTERNOON INTO THIS EVENING...AND COLD ADVECTION WIND GUSTS
ON THE OCEAN WATERS WILL BE AT MARGINAL SMALL CRAFT LEVELS. IN
ADDITION SEAS WILL STILL BE AT SMALL CRAFT LEVELS AND SLOWLY
SUBSIDING. SEAS MAY FALL BELOW SMALL CRAFT LATE TONIGHT INTO EARLY
TUESDAY. HOWEVER...WITH A STRONG AND GUSTY NORTHEAST TO EAST FLOW
DEVELOPING TUESDAY AS HIGH PRESSURE MOVES THROUGH NEW ENGLAND AND
A WAVE OF LOW PRESSURE ON THE COLD FRONT BEGINS TO MOVE NORTH WIND
GUSTS WILL AGAIN BE AT SMALL CRAFT LEVELS AND OCEAN SEAS WILL
BUILD. WITH HIGH CONFIDENCE IN SMALL CRAFT CONDITIONS HAVE
EXTENDED THE ADVISORY THROUGH TUESDAY.
EXPECT SCA CONDS ON ALL WATERS TUE NIGHT...WITH MODERATE E FLOW
BETWEEN DEPARTING STRONG HIGH PRESSURE AND AN APPROACHING WARM FRONT
AND ACCOMPANYING WEAK SFC LOW. GUSTS ON THE OCEAN COULD APPROACH
MINIMAL GALE FORCE...ESPECIALLY OUT EAST...AND SEAS COULD BUILDS AS
HIGH AS 9 FT. SCA CONDS SHOULD THEN PERSIST ON THE OCEAN INTO
WED-WED NIGHT AS THE WARM FRONT LIFTS TO THE N AND MODERATE SW FLOW
AHEAD OF A COLD FRONT GUSTS UP TO 25 KT DURING THE DAY ON WED...
FOLLOWED BY LINGERING SEAS ABOVE 5 FT WED NIGHT. GENERALLY QUIET
CONDS EXPECTED FOR THU-FRI AS HIGH PRESSURE BUILDS IN...BUT OCEAN
SEAS COULD APPROACH 5 FT FRI NIGHT AS NE FLOW SOUTH OF THE HIGH
INCREASES.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED TODAY THROUGH TUESDAY
MORNING. QPF WITH THE WARM FRONTAL APPROACH/PASSAGE FROM LATE
DAY TUE INTO WED MORNING SHOULD BE ABOUT 3-4 TENTHS OF AN INCH.
SOME OF THIS SHOULD FALL AS SNOW ACROSS INTERIOR LOCATIONS. NO
HYDROLOGIC IMPACTS ARE EXPECTED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...GOODMAN/MET
NEAR TERM...TONGUE
SHORT TERM...MET
LONG TERM...GOODMAN
AVIATION...BC
MARINE...GOODMAN/MET
HYDROLOGY...GOODMAN/MET
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1015 PM EST TUE DEC 2 2014
...SEA FOG EXPECTED TO MOVE OVER SE GA COASTAL WATERS WITHIN THE
NEXT HOUR...
.MARINE...ISSUED A MARINE DENSE FOG ADVISORY FOR THE GA COASTAL
WATERS THROUGH 9 AM AS FOG BANK DRIFT SOUTHWARD. SHOWERS CONTINUED
TO IMPACT THE FL COASTAL WATERS. THE HRRR MODEL HAD A DECENT
HANDLE ON THE FOG PROGRESS THIS EVENING...AND SHOWS THE SEA FOG
BANK DRIFTING SOUTHWARD TO NEAR JAX THROUGH WED MORNING...WHILE
MORE TURBULENT MIXING OVER THE MAJORITY OF THE FL WATERS KEEPS
DENSE FOG AT BAY. UPDATED THE FORECAST TO REFLECT THESE TRENDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 77 54 75 54 / 20 10 10 10
SSI 73 58 71 54 / 10 10 20 0
JAX 78 57 77 53 / 20 20 20 0
SGJ 75 60 75 58 / 30 40 20 10
GNV 82 57 79 55 / 20 20 20 0
OCF 82 57 80 56 / 30 20 20 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EST WEDNESDAY
FOR FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
DENSE FOG ADVISORY UNTIL 9 AM EST WEDNESDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-ALTAMAHA
SOUND GA TO FERNANDINA BEACH FL OUT 20 NM.
&&
$$
ENYEDI/ZIBURA
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
738 PM EST TUE DEC 2 2014
...EVENING COASTAL SHOWERS THEN AREAS OF SEA FOG DRIFTING INLAND
FROM THE NORTH AFTER MIDNIGHT...
.UPDATE...SHORT RANGE MODELS WERE NOT DEPICTING THE CLUSTER OF
SHOWERS THAT ERUPTED OFFSHORE OF THE FL EAST COAST THIS EVENING
ALONG THE AXIS OF A COASTAL TROUGH. UPDATED THE FORECAST TO
REFLECT 30-40% CHANCE OF EVENING SHOWERS GENERALLY FROM JAX
SOUTHWARD TO FLAGLER BEACH...THEN THE WX STORY SHIFTS TO SEA FOG
IMPACTING THE FORECAST AREA FROM THE NNE AFTER MIDNIGHT. THE HRRR
FINALLY HAD A DECENT HANDLE ON THE AREA OF SEA FOG DRIFTING SSW
OFFSHORE OF THE SC/GA COAST...AND TIME-OF-ARRIVAL TOOLS INDICATE
THIS FOG BANK ENTERING OUR GA WATERS WITHIN THE NEXT COUPLE OF
HOURS...THEN THE HRRR ADVERTISES THE FOG/STRATUS OVERSPREADING
INLAND SE GA AND INTO NE FL THROUGH SUNRISE WHILE SHOWER ACTIVITY
BECOMES MORE SPARSE AS DRIER MID LEVEL AIR POSITIONS OVER THE
AREA. UPDATE THE FORECAST TO REFLECT AREAS OF FOG WITH PATCHY
DENSE AFTER MIDNIGHT FOR MOST ZONES. TEMPS WERE ON TRACK TO FALL
INTO THE MID 50S TO UPPER 60S UNDER MOSTLY CLEAR TO PARTLY CLOUDY
SKIES.
&&
.AVIATION...VCSH AT CRG THE NEXT FEW HOURS AS SHOWERS OVER THE
WATERS APPROACH DUVAL COUNTY. EXPECT SEA FOG NOW ALONG THE SC COAST
TO REACH SSI AFTER 03Z WITH LIFR CONDITIONS EXPECTED THERE OVERNIGHT
TIL AROUND 13Z-14Z. HAVE TEMPO LIFR CONDITIONS AT INLAND NE FL TAFS
MAINLY 08Z-12Z DUE TO PATCHY DENSE RADIATIONAL FOG.
&&
.MARINE...ISSUED AN EARLY EVENING UPDATE TO REFLECT SEA FOG EDGING
SOUTHWARD DOWN THE ATLANTIC COAST AND PERSISTING OVERNIGHT
TONIGHT. COULD HAVE PERIODS OF VISIBILITIES LESS THAN 1 NM OVER THE
NEARSHORE WATERS AND OFFSHORE GA WATERS THROUGH WED MORNING.
ELEVATED SEAS IN THE 7-8 FT RANGE PERSISTED AT BUOY 41009 WITH
EAST WINDS SUSTAINED 18 KTS AND GUSTS TO 23 KTS...SO WILL
CONTINUE WITH THE SMALL CRAFT ADVISORY DUE TO SEAS FOR OUR
OFFSHORE FL LEGS AND EXERCISE CAUTION OF OUR GA OFFSHORE LEG.
RIP CURRENTS: MODERATE RISK OF RIPS EXPECTED WED
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 54 75 54 73 / 10 10 10 10
SSI 58 71 54 69 / 10 20 0 10
JAX 57 77 53 73 / 20 20 0 10
SGJ 60 75 58 72 / 40 20 10 20
GNV 57 79 55 76 / 20 20 0 10
OCF 57 80 56 78 / 20 20 10 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EST WEDNESDAY
FOR FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
&&
$$
ENYEDI/ZIBURA/WALSH
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
100 AM EST MON DEC 1 2014
.SYNOPSIS...
HIGH PRESSURE WILL PREVAIL TODAY. A COLD FRONT WILL ADVANCE FROM
THE NORTH TUESDAY...FOLLOWED BY A WEAK WEDGE OF HIGH PRESSURE. A
STRONGER WEDGE OF HIGH PRESSURE WILL DEVELOP LATE WEEK INTO NEXT
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
IT APPEARS A WIDESPREAD DENSE FOG EVENT IS IN THE OFFING FOR MUCH
OF THE AREA TONIGHT. CALM WINDS AT THE SURFACE AND THE KCLX VAD WIND
PROFILE SHOWS LIGHT/VARIABLE WINDS UP TO 4 KFT...SUGGESTING VERY
LITTLE WIND EXISTS EVEN ATOP THE NOCTURNAL INVERSION. ABUNDANT
LOW-LEVEL MOISTURE IS IN PLACE WITH DEWPOINTS RUNNING ABOUT 8-12
DEGREES HIGHER THAN 24 HOURS AGO. CLEAR SKIES...RICH LOW-LEVEL
MOISTURE AND CALM WINDS WILL SUPPORT ANOTHER ROUND OF DENSE FOG--
SIMILAR...IF NOT MORE DENSE/WIDESPREAD... THAN WHAT OCCURRED THIS
MORNING.
HIGH RESOLUTION DATA SETS INCLUDING THE RAP AND H3R HAVE BEEN
CONSISTENT FOR MANY CONSECUTIVE RUNS NOW IN THEIR DEPICTION OF
WIDESPREAD DENSE FOG ENCOMPASSING ALL OF SOUTHEAST SOUTH CAROLINA
AND SOUTHEAST GEORGIA AFTER MIDNIGHT... ESPECIALLY FROM 2-3 AM ON.
GOES-EAST IFR PROBABILITIES HAVE BEEN STEADILY INCREASING EAST OF
I-95 OVER THE PAST FEW HOURS AND A FEW OBSERVATION SITES HAVE BEEN
REPORTING VSBYS AS LOW AS 1 MILES ALREADY...SUGGESTING DENSE FOG
INITIATION HAS BEGUN. A DENSE FOG ADVISORY MAY BE ISSUED FOR ALL
OR PORTIONS OF THE FORECAST AREA OVERNIGHT.
FOR THE MIDNIGHT UPDATE WE MADE VERY MINOR ADJUSTMENTS TO HOURLY
DEWPOINTS AND TEMPERATURES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/...
MONDAY...THE PATTERN AT THE SURFACE AND ALOFT WILL BE
TRANSITIONING THROUGH THE DAY...AS DEEP LAYER RIDGING RETREATS
FARTHER INTO THE ATLANTIC AHEAD OF A COLD FRONT APPROACHING FROM
THE NORTHWEST. ONCE FOG DISSIPATES BY MID MORNING...MOSTLY CLEAR
TO PARTLY CLOUDY SKIES WILL ALLOW SUFFICIENT INSOLATION WITHIN
WARM SOUTHWEST FLOW TO SUPPORT ANOTHER UNSEASONABLY WARM DAY. WILL
ADVERTISE HIGH TEMPERATURES PEAKING IN THE LOW TO MID 70S AWAY
FROM THE LOCALLY COOLER COASTLINE. WILL NEED TO MONITOR THE
POTENTIAL FOR FOG DEVELOPMENT AFTER MIDNIGHT...AS SEVERAL
GUIDANCE SOURCES SUGGEST AREAS OF FOG COULD AGAIN IMPACT PORTIONS
OF THE FORECAST AREA ONCE LOW LEVEL MOISTURE BECOMES TRAPPED
BENEATH THE INVERSION. EXPECT MILDER LOW TEMPERATURES RANGING FROM
THE UPPER 40S TO LOW 50S.
TUESDAY...THE FRONT WILL LIKELY STALL IN THE VICINITY AND FORM THE
LEADING EDGE OF AN INLAND WEDGE OF HIGH PRESSURE BUILDING DOWN THE
LEE OF THE APPALACHIANS. THE PARENT SURFACE HIGH WELL TO THE NORTH
WILL BE RATHER TRANSIENT IN NATURE...AND THUS THERE IS SOME
UNCERTAINTY REGARDING THE STRENGTH OF THE WEDGE AND ITS ASSOCIATED
SENSIBLE WEATHER IMPACTS. PREFER TO MAINTAIN PERSISTENCE AT THIS
TIME AND INDICATE A RATHER SHARP TEMPERATURE GRADIENT FROM
NORTHWEST TO SOUTHEAST...AS IS EXPECTED IN A WEDGE TYPE SCENARIO.
WILL ADVERTISE HIGH TEMPERATURES RANGING FROM THE LOW 60S
CHARLESTON TRI COUNTY REGION TO THE LOW 70S FARTHER SOUTH NEAR THE
ALTAMAHA RIVER IN GEORGIA. ANY MEASURABLE PRECIPITATION IS
EXPECTED TO REMAIN OVER THE MARINE ZONES AND POSSIBLY THE ADJACENT
COASTLINE...CLOSEST TO MOISTURE CONVERGENCE WITHIN A WEAK COASTAL
TROUGH. THE MAJORITY OF THE FORECAST AREA WILL SEE MOSTLY CLOUDY
SKIES THROUGH THE NIGHT...KEEPING LOW TEMPERATURES IN THE UPPER
40S INLAND TO THE LOW 50S NEAR THE COAST.
WEDNESDAY...THE CENTER OF THE SURFACE HIGH WILL SHIFT OFF THE NEW
ENGLAND COAST...WHILE THE INLAND WEDGE STEADILY WEAKENS AND
BECOMES ORIENTED ALONG THE MID ATLANTIC AND SOUTHEAST COAST.
EXPECT THE TEMPERATURE GRADIENT TO BE LESS DEFINED AS A
RESULT...WITH HIGHS RANGING FROM THE THE UPPER 60S TO NEAR 70
DEGREES. CLOUDS COULD LINGER FOR MUCH OF THE DAYTIME
PERIOD...ESPECIALLY INLAND...WHILE RAIN CHANCES REMAIN LESS THAN A
MENTIONABLE 15 PERCENT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE UPPER PATTERN BECOMES MORE AMPLIFIED LATE IN THE WEEK INTO THE
WEEKEND THOUGH THE COLD AIR REMAINS WELL TO THE NORTH. CANADIAN HIGH
PRESSURE WILL CONTINUE TO TRY TO WEDGE DOWN THE EASTERN SEABOARD BUT
WITH A BUILDING 850 MB RIDGE AND LACK OF MOISTURE OR FORCING TO
PRODUCE PRECIPITATION...TEMPERATURES WILL STAY NEAR NORMAL ALBEIT
WITH GREATER CLOUD COVER. HIGHS WILL GENERALLY BE IN THE MID/UPPER
60S WITH LOWS IN THE MID/UPPER 40S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
BIGGEST CONCERN IS FOR DENSE FOG TO AFFECT THE TERMINALS OVERNIGHT
INTO MID MORNING. OUR CONFIDENCE REMAINS HIGHEST AT KSAV WHERE VSBYS
MAY DROP TO LESS THAN 1/4SM WITH VERTICAL VISIBILITIES 100 FT OR
LESS LATER TONIGHT. CONFIDENCE IS NOT AS HIGH AT KCHS...BUT MODELS
CONTINUE TO TREND WITH LOWER CONDITIONS. ON THE 06Z TAF RELEASE...WE
MAINTAINED TRENDS SET FROM THE PREVIOUS CYCLE BUT SLIGHT DIFFERENCES
IN THE LOWEST LEVEL THERMAL/MOISTURE PROFILES FROM LAST NIGHT HAVE
BEEN NOTED WITH UNCERTAINTY IN HOW THESE SUBTLETIES COME INTO
PLAY....IF AT ALL. FOG WILL BURN OFF BY 15Z AT BOTH TERMINALS AND
THEN VFR THROUGH 06Z TUESDAY.
EXTENDED AVIATION OUTLOOK...VISIBILITY RESTRICTIONS ARE POSSIBLE
IN FOG LATE MON NIGHT AND EARLY TUESDAY. MVFR OR LOWER CEILINGS
ARE POSSIBLE TUESDAY INTO WEDNESDAY DUE TO LOW-LEVEL MOISTURE IN
THE WAKE OF THE COLD FRONT. VISIBILITY AND/OR CEILING RESTRICTIONS
POSSIBLE THURSDAY MORNING.
&&
.MARINE...
OVERNIGHT...VARIABLE WINDS 5 KT OR LESS WITH SEAS 1-2 FT WILL
DOMINATE THE WATERS TONIGHT. AREAS OF FOG ARE LIKELY NEAR THE
COAST WITH VSBYS 1-3 NM...LOCALLY LESS THAN 1 NM. IN THE
CHARLESTON HARBOR...VSBYS COULD DROP TO LESS THAN 1/2 NM. A MARINE
DENSE FOG ADVISORY MAY VERY WELL BE NEEDED OVERNIGHT.
MONDAY THROUGH FRIDAY...WEAK HIGH PRESSURE WILL
PERSIST INTO MONDAY. A BACKDOOR COLD FRONT WILL THEN DESCEND INTO
THE WATERS TUESDAY...WITH A WEDGE OF HIGH PRESSURE BUILDING IN
FROM THE NORTH AND TIGHTENING THE GRADIENT WITHIN WEAK COLD
ADVECTION. MARGINAL SMALL CRAFT ADVISORY CONDITIONS ACROSS THE
OFFSHORE WATERS ARE POSSIBLE TUESDAY NIGHT...MAINLY FOR SEAS
BUILDING TO 6 FT OVER OFFSHORE GEORGIA WATERS TUESDAY NIGHT
THROUGH MIDDAY WEDNESDAY. THEREAFTER...THE GRADIENT RELAXES QUITE
A BIT...AND THE POSSIBILITY FOR ADDITIONAL ADVISORIES WANES LATE
IN THE WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
904 PM CST TUE DEC 2 2014
.UPDATE...
842 PM CST
FOR EVENING UPDATE...
MINOR CHANGES TO GOING FORECAST THIS EVENING...MAINLY TO SLOW RATE
OF TEMPERATURE FALL A BIT THIS EVENING WHERE EXTENSIVE CLOUD
COVER AND SOUTHWEST WINDS AND LOW LEVEL MOISTURE ADVECTION WAS
KEEPING TEMPS FAIRLY STEADY AHEAD OF APPROACHING COLD FRONT. OTHER
CHANGE OF NOTE WAS TO ADD A MENTION OF FLURRIES FOR THE FAR NORTHERN
TIER OF ILLINOIS COUNTIES THROUGH MIDNIGHT...WITH A FEW REPORTS OF
SNOW FLAKES REACHING THE SURFACE FROM ADJACENT DVN AND MKX COUNTIES.
WEAK SURFACE LOW PRESSURE WAVE WAS MOVING EAST ACROSS LAKE SUPERIOR
THIS EVENING...TRAILING A WEAK SURFACE TROUGH/COLD FRONT SOUTHWEST
INTO CENTRAL IOWA. EAST OF THIS BOUNDARY...SOUTHWEST LOW LEVEL WINDS
WERE LIFTING RELATIVELY MILD/MOIST LOW LEVEL AIR NORTHWARD ACROSS
THE FORECAST AREA BENEATH EXTENSIVE LOW CLOUD SHIELD. TEMPS IN THE
LOW 30S AND DEW POINTS IN THE MID 20S-AROUND 30 ARE CHARACTERISTIC
OF THE AIR MASS HERE...WITH NOTABLY DRIER AIR TO OUR WEST WHERE DEW
POINTS DIP INTO THE TEENS. ALOFT...A MID-LEVEL SHORT WAVE WAS MOVING
THROUGH THE BASE OF A BROAD UPPER TROUGH OVER THE UPPER MIDWEST...
PRODUCING LIFT AND AN AREA OF ENHANCED MID-UPPER LEVEL MOISTURE FROM
UPPER AND NORTHERN LOWER MICHIGAN BACK INTO NORTHERN IL. MODEST
RADAR RETURNS WERE NOTED AS FAR SOUTHWEST AS NORTHWEST IL...WITH DVN
REPORTING A FEW FLURRIES ACROSS THEIR NORTHERN CWA AND SEVERAL OBS
OF LIGHT SNOW ACROSS SOUTHERN WI. DVN 00Z RAOB INDICATED A
SUBSTANTIAL WARM LAYER OF +4 C AROUND 800 MB...LIKELY SAMPLED JUST
AHEAD OF BETTER MID-LEVEL MOISTURE PER IR SATELLITE LOOP...THOUGH
DOES INDICATE RATHER DRY LAYER FOR ANY PRECIP TO SURVIVE TO THE
SURFACE. BEST CHANCES APPEAR TO BE RIGHT ALONG THE WI/IL BORDER
WHERE A FEW FLURRIES MAY ACCOMPANY SOME OF THE THICKER/COLDER CLOUDS
THROUGH MIDNIGHT. NO ACCUMULATION EXPECTED.
FARTHER SOUTH...A FEW SPOTS REPORTING SOME HAZE/LIGHT FOG AND EVEN A
LITTLE VERY FINE DRIZZLE OR MIST. THIS BARELY PERCEPTIBLE HERE AT
WFO LOT AND SUSPECT IT WONT BE AN ISSUE...THOUGH WILL CONTINUE TO
MONITOR FOR ANY LIGHT FREEZING DRIZZLE POTENTIAL OVER THE NEXT FEW
HOURS BEFORE DRIER LOW LEVEL AIR ARRIVES. ILX 00Z SOUNDING SHOWS
STORY HERE...WITH SHALLOW MOIST LAYER WITH COOLEST TEMP IN LAYER
ONLY ABOUT -4 C AND DRY ABOVE INDICATING NO ICE IN COLUMN.
OTHERWISE...HAVE SLOWED TREND OF CLOUD DECREASE FROM THE WEST A BIT
AS WELL...MAINLY AFTER MIDNIGHT THROUGH EARLY WEDNESDAY MORNING.
RATZER
&&
.SHORT TERM...
256 PM CST
TONIGHT THROUGH FRIDAY...
THE THEME OF THE FORECAST IS CONTINUED SEASONABLY COOL AND
DRY...WITH PERIODS OF NEAR TO...FOR DECEMBER...SLIGHTLY ABOVE NORMAL
TEMPERATURES OVER THE WEEKEND. THE LARGE SCALE WEATHER PATTERN IS
CHARACTERIZED BY AN UPPER TROUGH OVER NORTH CENTRAL CANADA WITH
QUASI-ZONAL FLOW DRAPED ACROSS EAST CENTRAL USA. OUR NECK OF THE
WOODS IS ON THE SOUTHERN END OF THE TROUGH AXIS...WITH SOME
SHORTWAVE ENERGY RIDING THROUGH THE BASE OF THE TROUGH INTO MN/WI. A
FEW ADDITIONAL TROUGHS LIE OFF THE CALIFORNIA COAST AND OFF THE TIP
OF ALASKA. AT THE SURFACE...STRONG HIGH PRESSURE IS IN NEW ENGLAND
WHILE WEAKER HIGH PRESSURE EXTENDS OVER OUR AREA SW TO THE MID
MISSOURI VALLEY...WITH WEAK LOW PRESSURE SLIDING SOUTHEAST INTO
NORTHERN MINNESOTA.
STRATUS IS SURGING NORTHWARD AS PRESSURE LOWERS TO THE
NORTH...THOUGH THERE IS A BACK EDGE APPROACHING THE MISSISSIPPI
RIVER ON THE LEADING EDGE OF DRIER AIR IN THE PLAINS. THE ENERGY
AT THE BASE OF THE CANADIAN TROUGH WILL CONTINUE TO SLIDE EAST
TODAY. THE MOISTURE STARVED SYSTEM...PW`S UNDER 0.3 IN...WILL
CONTINUE TO RESULT IN HIGH CLOUDS AND VERY LIGHT SNOW TO OUR
NORTH. THE WEAK SURFACE LOW IN NORTHERN MINNESOTA WILL SLIDE TO
LAKE SUPERIOR TONIGHT. AS THIS OCCURS A COLD FRONT WILL APPROACH
FROM THE NW...BUT CONVERGENCE ON THE FRONT IS WEAK...SO NOT
EXPECTING MUCH OUT OF THIS. THE LOW LEVEL MOISTURE GETS SHUNTED
EAST QUICKLY WITH APPROACH OF DRIER AIR FROM THE NORTHWEST THIS
EVENING AND TONIGHT...THOUGH SOME MID AND HIGHER CLOUDS WILL DRIFT
THROUGH OVERNIGHT WITH THE TROUGH.
THE SURFACE LOW WILL DEEPEN QUITE A BIT MORE NEAR JAMES BAY ON
WEDNESDAY...BUT BY THIS TIME THE SHORTWAVE ENERGY WILL BE EAST OF
OUR AREA. WE GET A BRIEF REINFORCING SHOT OF SLIGHTLY COLDER
AIR...SHOULD SEE A BIT MORE SUNSHINE AFTER ANY LINGERING LOWER LEVEL
MOISTURE IN THE SOUTHEAST ERODES. SURFACE HIGH BUILDS IN LATE IN THE
DAY AND OVERNIGHT...RESULTING IN A CRISP AND DRY NIGHT WEDNESDAY
NIGHT.
THE SURFACE HIGH RETREATS SLOWLY ON THURSDAY AS THE FLOW ALOFT TURNS
ZONAL AGAIN. THE TROUGH OFF THE CALIFORNIA COAST DISSOLVES...BUT
SOME WEAK ENERGY ASSOCIATED WITH IT RAPIDLY MOVES EASTWARD.
MOISTURE TRANSPORT INCREASES IN THE SOUTHWEST FLOW AHEAD OF THIS
DISTURBANCE. ISENTROPIC LIFT REALLY DOES NOT GET GOING INTO THURSDAY
NIGHT AND MORE SO FRIDAY...SO REMOVED SLIGHT CHANCE MENTION FOR
THURSDAY. LOOKS LIKE BEST ISENTROPIC LIFT COINCIDES WITH MOISTURE TO
OUR SOUTH...AND THE ECMWF CONTINUES A CONSISTENT TREND OF PRECIP
REMAINING SOUTH OF I-80. KEPT SOME SMALL POPS NORTH WITH THE GFS
HOLDING ONTO SOME PRECIP...BUT FEEL THAT MUCH OF THIS WILL SLIDE BY
TO THE SOUTH AS WE HANG ONTO A DRIER NE FLOW.
KMD
&&
.LONG TERM...
256 PM CST
SATURDAY THROUGH TUESDAY...
IT APPEARS TO BE A BENIGN AND MILDER PATTERN FOR THE WEEKEND. QUIET
WESTERLY FLOW ALOFT AND SURFACE HIGH PRESSURE IN CONTROL. NORTHEAST
FLOW WILL KEEP THINGS A BIT COOLER...THEN HIGH PRESSURE SHIFTS
SOMEWHAT EAST SUNDAY. HIGH PRESSURE ALOFT OFF IN THE ATLANTIC KEEPS
THE CANADIAN TROUGH AT BAY...AND THEREFORE ALLOWS SHORTWAVE ENERGY
CURRENTLY OFF THE ALASKA COAST TO PUSH SOUTHWEST OUT OF THE CANADIAN
ROCKIES IN A CLIPPER-LIKE MANNER SUNDAY NIGHT INTO MONDAY. MODELS
ARE MIXED AS TO WHETHER WE GET ANY PRECIP WITH THIS WITH THE
"WETTER" GFS JUST GRAZING THE AREA WITH SOME LIGHT RAIN TURNING TO
POSSIBLY SNOW...WHILE THE EC IS DRY WITH THE ENERGY HEADING NORTH.
THE PATTERN LOOKS TO AMPLIFY SOME BY EARLY TO MID NEXT WEEK...BUT
NOT UNTIL AFTER A PERIOD OF DRY AND COOLER NORTHERLY FLOW TO START
THE WEEK. EVENTUALLY THIS WILL ALLOW A RIDGE IN THE WEST TO MAKE
SOME HEADWAY EASTWARD BUT THIS APPEARS TO HAVE SLOWED A LITTLE BIT.
MODELS HAVE MODERATE PREDICTABILITY ON THIS FEATURE AT THIS TIME
WHICH WOULD BRING DRY AND MILDER WEATHER.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* DURATION AND EXTENT OF MVFR CIGS/VIS THIS EVENING.
KREIN
//DISCUSSION...UPDATED 03Z...
HIGHER DEWPOINT AIR IS ADVECTING INTO THE REGION IN THE SOUTHWEST
FLOW AHEAD OF A WEAK COLD FRONT. IN THIS AIRMASS...DEWPOINTS HAVE
CLIMBED INTO THE UPPER 20S TO LOWER 30S AS TEMPS HAVE DROPPED INTO
THE LOWER 30S. VIS HAS DROPPED TO 3-5SM AT MANY LOCATIONS. LATEST
SOUNDINGS INDICATE A SHALLOW SATURATED LAYER BELOW A WARM/DRY
LAYER BASED AT ARND 5KFT. THIS SATURATED LAYER IS JUST THICK
ENOUGH TO GENERATE A FINE MIST OR LIGHT DRIZZLE...ALLOWING VIS TO
DROP INTO MVFR LEVELS. BEHIND THE BOUNDARY...DEWPOINTS ARE MUCH
LOWER...ONLY IN THE TEENS TO UPPER SINGLE DIGITS...SO EXPECT THAT
VISIBILITY WILL IMPROVE TO UNRESTRICTED WHILE SKIES SCATTER OUT
FOLLOWING THE PASSAGE OF THE BOUNDARY. TIMING THE BACK EDGE OF THE
CLOUD COVER ON THE LATEST SATELLITE IMAGERY SUGGESTS THAT RFD
SHOULD IMPROVE TO VFR BY ARND 0530-0600Z...WHILE THE CHICAGO AREA
TERMINALS SHOULD IMPROVE TO VFR BTWN 0630-0730Z.
FOLLOWING THE PASSAGE OF THE BOUNDARY WINDS SHOULD SHIFT FROM SWLY
TO WLY AND DROP OFF FROM ARND 10 KT TO ARND 5 KT.
STILL ANTICIPATE CLEARING SKIES FOR WEDNESDAY AS HIGH PRESSURE
MOVES ACROSS THE AREA WITH WEST WINDS ARND 10 KT.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MEDIUM CONFIDENCE IN CIG/VIS TRENDS.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY...VFR/WX NIL. ELY TO SELY WINDS.
FRIDAY...SLIGHT CHANCE RAIN. MVFR POSSIBLE. SELY BECMG NELY
WINDS.
SATURDAY...SLIGHT CHANCE RAIN EARLY. MVFR POSSIBLE. NELY WINDS
BECMG ELY.
SUNDAY...SLIGHT CHANCE RAIN/SNOW LATE. IFR POSSIBLE LATE. SELY WINDS
BECMG WLY.
MONDAY...SLIGHT CHANCE RAIN/SNOW EARLY. IFR POSSIBLE EARLY. SELY WINDS
BECMG WLY.
KREIN
&&
.MARINE...
123 PM CST
HIGH PRESSURE TO THE EAST OF THE LAKE AND A TROUGH OF LOW PRESSURE
APPROACHING FROM THE WEST HAS ALLOWED FOR SOUTHERLY WINDS
TODAY...WITH HIGHEST SPEEDS TO 30 KT BEING OBSERVED OVER THE
NORTHERN HALF OF THE LAKE. THESE SAME SPEEDS WILL LIKELY CONTINUE
TONIGHT BUT WITH WINDS BECOMING MORE WESTERLY AS THIS TROUGH AND
FRONTAL BOUNDARY MOVE ACROSS THE LAKE THROUGH WEDNESDAY MORNING.
SPEEDS WILL BRIEFLY COME DOWN WEDNESDAY MORNING WITH THE DEPARTURE
OF THIS TROUGH...BUT WILL INCREASE IN THE AFTERNOON AS HIGH
PRESSURE BUILDS SOUTHEAST ACROSS THE REGION. EXPECT ANOTHER PERIOD
OF TO 30 KT WINDS OVER THE ENTIRE LAKE WEDNESDAY AFTERNOON INTO
THE NIGHT...BEFORE WINDS DIMINISH INTO THURSDAY MORNING AS THIS
HIGH MOVES OVERHEAD. THIS HIGH WILL SHIFT TO THE EAST THURSDAY
INTO THURSDAY NIGHT...WITH A PERIOD OF SOUTHERLY FLOW EXPECTED
THROUGH THE END OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 4 AM THURSDAY.
&&
$$
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
855 PM CST Tue Dec 2 2014
.UPDATE...
ISSUED AT 845 PM CST TUE DEC 2 2014
Backedge of clouds over west central Illinois continues to make
steady progress to the east this evening. We expect this trend
to continue during the overnight hours with most of the short
term models indicating the backedge of the clouds should push
into far east central Illinois by dawn Wednesday. A weak front
to our northwest will push across our area Wednesday morning
with little in the way of sensible weather other than a wind
shift into the west and northwest as high pressure builds east
into the Midwest for the remainder of the day. Will have the
updated zones out by 900 pm.
&&
.SHORT TERM...(Tonight)
ISSUED AT 310 PM CST TUE DEC 2 2014
20z/2pm surface analysis shows ridge axis extending from the Great
Lakes to Texas. Despite presence of high pressure, low-level
moisture remains trapped beneath a strong subsidence inversion
evident on latest LAPS soundings, which has resulted in overcast
conditions across central Illinois this afternoon. Visible
satellite imagery shows back edge of clouds slowly eroding across
central Missouri, with satellite timing tools bringing the clearing
into the western KILX CWA by mid-evening. Latest HRRR has a similar
trend, suggesting clearing skies from west to east by mid to late
evening. Based on satellite trends and expected southwesterly
return flow on the back side of the departing high, think skies will
become mostly clear across locations along/northwest of a
Taylorville to Champaign line by midnight. Further southeast, cloud
cover will be much slower to exit, with soundings indicating mostly
cloudy skies through the entire night across the far E/SE CWA. Due
to the initial cloud cover and a light southwesterly wind, have gone
2 to 3 degrees above MAV guidance for lows tonight, with readings
ranging from the lower 20s far northwest around Galesburg to the
lower 30s far southeast.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 310 PM CST TUE DEC 2 2014
Morning upper air and moisture channel satellite data shows minor
upper wave moving east across the northern US, approaching Great
Lakes. This system will drag a weak cold front into IL region on
early on Wednesday, coming through dry and bringing high pressure in
behind it.
Main system to affect area is currently off the west coast. Forecast
models bring a wave east from the offshore low, it tracking east
over the western state through day Thursday. southerly low level
flow expected to develop Thursday in response to the system exiting
the Rockies. Overrunning flow will develop precipitation by late
Thursday, but will not reach region till Thursday night, so dropped
Thursday pcpn. Pops spreading into the CWA Thursday night. With
temperature though near freezing, possibly some freezing rain in the
central and north central parts of IL Thursday night, before
temperatures rise Friday morning with the bulk of pcpn on Friday and
Friday night.
Track of the developing surface low is still a little uncertain, as
GFS brings low across KY and EUR across northern AL. Pcpn to
gradually pull out on Saturday, and will be faster if EUR solution
is right.
Weak northern stream system to again move over Great Lakes on
Monday, but have kept forecast dry at this time, again due to the
differences in the models on track and moisture.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 525 PM CST TUE DEC 2 2014
MVFR with local IFR cigs continue over the forecast area early
this evening but the latest satellite imagery indicates clearing
taking place just west of the Mississippi River. Latest timing
has the backedge of the clouds at PIA and SPI between 02 and 03z
and at BMI and DEC around 04z...and finally over in CMI btwn
05z and 06z. The latest high resolution models have trended slower
with the clearing, especially across our eastern counties with
the RAP and HRRR suggesting clearing over the CMI TAF not occurring
until after 09z. For now will go with continuity based on the present
movement of the clouds to the east with all of our area seeing VFR
conditions by late tonight which will continue through Wednesday.
Surface winds will be southwest at around 10 kts tonight and then
switch into a west to northwest direction mid-morning Wednesday
as a weak frontal boundary shifts across the area. Speeds during
the day will average from 10 to 15 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
600 PM CST TUE DEC 2 2014
.SHORT TERM...
256 PM CST
TONIGHT THROUGH FRIDAY...
THE THEME OF THE FORECAST IS CONTINUED SEASONABLY COOL AND
DRY...WITH PERIODS OF NEAR TO...FOR DECEMBER...SLIGHTLY ABOVE NORMAL
TEMPERATURES OVER THE WEEKEND. THE LARGE SCALE WEATHER PATTERN IS
CHARACTERIZED BY AN UPPER TROUGH OVER NORTH CENTRAL CANADA WITH
QUASI-ZONAL FLOW DRAPED ACROSS EAST CENTRAL USA. OUR NECK OF THE
WOODS IS ON THE SOUTHERN END OF THE TROUGH AXIS...WITH SOME
SHORTWAVE ENERGY RIDING THROUGH THE BASE OF THE TROUGH INTO MN/WI. A
FEW ADDITIONAL TROUGHS LIE OFF THE CALIFORNIA COAST AND OFF THE TIP
OF ALASKA. AT THE SURFACE...STRONG HIGH PRESSURE IS IN NEW ENGLAND
WHILE WEAKER HIGH PRESSURE EXTENDS OVER OUR AREA SW TO THE MID
MISSOURI VALLEY...WITH WEAK LOW PRESSURE SLIDING SOUTHEAST INTO
NORTHERN MINNESOTA.
STRATUS IS SURGING NORTHWARD AS PRESSURE LOWERS TO THE
NORTH...THOUGH THERE IS A BACK EDGE APPROACHING THE MISSISSIPPI
RIVER ON THE LEADING EDGE OF DRIER AIR IN THE PLAINS. THE ENERGY
AT THE BASE OF THE CANADIAN TROUGH WILL CONTINUE TO SLIDE EAST
TODAY. THE MOISTURE STARVED SYSTEM...PW`S UNDER 0.3 IN...WILL
CONTINUE TO RESULT IN HIGH CLOUDS AND VERY LIGHT SNOW TO OUR
NORTH. THE WEAK SURFACE LOW IN NORTHERN MINNESOTA WILL SLIDE TO
LAKE SUPERIOR TONIGHT. AS THIS OCCURS A COLD FRONT WILL APPROACH
FROM THE NW...BUT CONVERGENCE ON THE FRONT IS WEAK...SO NOT
EXPECTING MUCH OUT OF THIS. THE LOW LEVEL MOISTURE GETS SHUNTED
EAST QUICKLY WITH APPROACH OF DRIER AIR FROM THE NORTHWEST THIS
EVENING AND TONIGHT...THOUGH SOME MID AND HIGHER CLOUDS WILL DRIFT
THROUGH OVERNIGHT WITH THE TROUGH.
THE SURFACE LOW WILL DEEPEN QUITE A BIT MORE NEAR JAMES BAY ON
WEDNESDAY...BUT BY THIS TIME THE SHORTWAVE ENERGY WILL BE EAST OF
OUR AREA. WE GET A BRIEF REINFORCING SHOT OF SLIGHTLY COLDER
AIR...SHOULD SEE A BIT MORE SUNSHINE AFTER ANY LINGERING LOWER LEVEL
MOISTURE IN THE SOUTHEAST ERODES. SURFACE HIGH BUILDS IN LATE IN THE
DAY AND OVERNIGHT...RESULTING IN A CRISP AND DRY NIGHT WEDNESDAY
NIGHT.
THE SURFACE HIGH RETREATS SLOWLY ON THURSDAY AS THE FLOW ALOFT TURNS
ZONAL AGAIN. THE TROUGH OFF THE CALIFORNIA COAST DISSOLVES...BUT
SOME WEAK ENERGY ASSOCIATED WITH IT RAPIDLY MOVES EASTWARD.
MOISTURE TRANSPORT INCREASES IN THE SOUTHWEST FLOW AHEAD OF THIS
DISTURBANCE. ISENTROPIC LIFT REALLY DOES NOT GET GOING INTO THURSDAY
NIGHT AND MORE SO FRIDAY...SO REMOVED SLIGHT CHANCE MENTION FOR
THURSDAY. LOOKS LIKE BEST ISENTROPIC LIFT COINCIDES WITH MOISTURE TO
OUR SOUTH...AND THE ECMWF CONTINUES A CONSISTENT TREND OF PRECIP
REMAINING SOUTH OF I-80. KEPT SOME SMALL POPS NORTH WITH THE GFS
HOLDING ONTO SOME PRECIP...BUT FEEL THAT MUCH OF THIS WILL SLIDE BY
TO THE SOUTH AS WE HANG ONTO A DRIER NE FLOW.
KMD
&&
.LONG TERM...
256 PM CST
SATURDAY THROUGH TUESDAY...
IT APPEARS TO BE A BENIGN AND MILDER PATTERN FOR THE WEEKEND. QUIET
WESTERLY FLOW ALOFT AND SURFACE HIGH PRESSURE IN CONTROL. NORTHEAST
FLOW WILL KEEP THINGS A BIT COOLER...THEN HIGH PRESSURE SHIFTS
SOMEWHAT EAST SUNDAY. HIGH PRESSURE ALOFT OFF IN THE ATLANTIC KEEPS
THE CANADIAN TROUGH AT BAY...AND THEREFORE ALLOWS SHORTWAVE ENERGY
CURRENTLY OFF THE ALASKA COAST TO PUSH SOUTHWEST OUT OF THE CANADIAN
ROCKIES IN A CLIPPER-LIKE MANNER SUNDAY NIGHT INTO MONDAY. MODELS
ARE MIXED AS TO WHETHER WE GET ANY PRECIP WITH THIS WITH THE
"WETTER" GFS JUST GRAZING THE AREA WITH SOME LIGHT RAIN TURNING TO
POSSIBLY SNOW...WHILE THE EC IS DRY WITH THE ENERGY HEADING NORTH.
THE PATTERN LOOKS TO AMPLIFY SOME BY EARLY TO MID NEXT WEEK...BUT
NOT UNTIL AFTER A PERIOD OF DRY AND COOLER NORTHERLY FLOW TO START
THE WEEK. EVENTUALLY THIS WILL ALLOW A RIDGE IN THE WEST TO MAKE
SOME HEADWAY EASTWARD BUT THIS APPEARS TO HAVE SLOWED A LITTLE BIT.
MODELS HAVE MODERATE PREDICTABILITY ON THIS FEATURE AT THIS TIME
WHICH WOULD BRING DRY AND MILDER WEATHER.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* DURATION AND EXTENT OF MVFR CIGS THIS EVENING.
KREIN
//DISCUSSION...UPDATED 00Z...
THE BASES OF THE MVFR STRATOCU DECK IS BECOMING A BIT MORE
IRREGULAR AND VARIABLE IN COVERAGE WITH BASES RANGING FROM 012 TO
030 ACROSS THE REGION WITH A FEW POCKETS OF VFR. FEEL CONFIDENT
THAT CIGS WILL NOT DROP TO IFR...BUT LESS CONFIDENT IN THE
DURATION OF MVFR CIGS AT THE TERMINALS...SO HAVE GONE WITH TEMPO
MVFR AT ORD/MDW/DPA WHERE CIGS HAVE BEEN A BIT MORE VARIABLE...
WHILE RFD/GYY HAVE MAINTAINED MVFR CIGS WITHOUT THE VARIABILITY.
THE BACK EDGE OF THE CLOUD DECK IS CURRENTLY MOVING ACROSS THE
MISSISSIPPI RIVER FROM IOWA TO NWRN IL...AND SHOULD STEADILY
PROGRESS EWD...WITH SKIES BECMG VFR FROM WEST TO EAST BTWN 03Z-
06Z. WINDS SHOULD REMAIN SWLY THROUGH THE NIGHT AT 7-10KT.
STILL ANTICIPATE CLEARING SKIES FOR WEDNESDAY AS HIGH PRESSURE
MOVES ACROSS THE AREA WITH WEST WINDS ARND 10 KT.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM CONFIDENCE IN CIG TRENDS THROUGH LATE THIS EVENING.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY...VFR/WX NIL. ELY TO SELY WINDS.
FRIDAY...SLIGHT CHANCE RAIN. MVFR POSSIBLE. SELY BECMG NELY
WINDS.
SATURDAY...SLIGHT CHANCE RAIN EARLY. MVFR POSSIBLE. NELY WINDS
BECMG ELY.
SUNDAY...SLIGHT CHANCE RAIN/SNOW LATE. IFR POSSIBLE LATE. SELY WINDS
BECMG WLY.
MONDAY...SLIGHT CHANCE RAIN/SNOW EARLY. IFR POSSIBLE EARLY. SELY WINDS
BECMG WLY.
KREIN
&&
.MARINE...
123 PM CST
HIGH PRESSURE TO THE EAST OF THE LAKE AND A TROUGH OF LOW PRESSURE
APPROACHING FROM THE WEST HAS ALLOWED FOR SOUTHERLY WINDS
TODAY...WITH HIGHEST SPEEDS TO 30 KT BEING OBSERVED OVER THE
NORTHERN HALF OF THE LAKE. THESE SAME SPEEDS WILL LIKELY CONTINUE
TONIGHT BUT WITH WINDS BECOMING MORE WESTERLY AS THIS TROUGH AND
FRONTAL BOUNDARY MOVE ACROSS THE LAKE THROUGH WEDNESDAY MORNING.
SPEEDS WILL BRIEFLY COME DOWN WEDNESDAY MORNING WITH THE DEPARTURE
OF THIS TROUGH...BUT WILL INCREASE IN THE AFTERNOON AS HIGH
PRESSURE BUILDS SOUTHEAST ACROSS THE REGION. EXPECT ANOTHER PERIOD
OF TO 30 KT WINDS OVER THE ENTIRE LAKE WEDNESDAY AFTERNOON INTO
THE NIGHT...BEFORE WINDS DIMINISH INTO THURSDAY MORNING AS THIS
HIGH MOVES OVERHEAD. THIS HIGH WILL SHIFT TO THE EAST THURSDAY
INTO THURSDAY NIGHT...WITH A PERIOD OF SOUTHERLY FLOW EXPECTED
THROUGH THE END OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ745...10 PM TUESDAY TO 4 AM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
532 PM CST Tue Dec 2 2014
.SHORT TERM...(Tonight)
ISSUED AT 310 PM CST TUE DEC 2 2014
20z/2pm surface analysis shows ridge axis extending from the Great
Lakes to Texas. Despite presence of high pressure, low-level
moisture remains trapped beneath a strong subsidence inversion
evident on latest LAPS soundings, which has resulted in overcast
conditions across central Illinois this afternoon. Visible
satellite imagery shows back edge of clouds slowly eroding across
central Missouri, with satellite timing tools bringing the clearing
into the western KILX CWA by mid-evening. Latest HRRR has a similar
trend, suggesting clearing skies from west to east by mid to late
evening. Based on satellite trends and expected southwesterly
return flow on the back side of the departing high, think skies will
become mostly clear across locations along/northwest of a
Taylorville to Champaign line by midnight. Further southeast, cloud
cover will be much slower to exit, with soundings indicating mostly
cloudy skies through the entire night across the far E/SE CWA. Due
to the initial cloud cover and a light southwesterly wind, have gone
2 to 3 degrees above MAV guidance for lows tonight, with readings
ranging from the lower 20s far northwest around Galesburg to the
lower 30s far southeast.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 310 PM CST TUE DEC 2 2014
Morning upper air and moisture channel satellite data shows minor
upper wave moving east across the northern US, approaching Great
Lakes. This system will drag a weak cold front into IL region on
early on Wednesday, coming through dry and bringing high pressure in
behind it.
Main system to affect area is currently off the west coast. Forecast
models bring a wave east from the offshore low, it tracking east
over the western state through day Thursday. southerly low level
flow expected to develop Thursday in response to the system exiting
the Rockies. Overrunning flow will develop precipitation by late
Thursday, but will not reach region till Thursday night, so dropped
Thursday pcpn. Pops spreading into the CWA Thursday night. With
temperature though near freezing, possibly some freezing rain in the
central and north central parts of IL Thursday night, before
temperatures rise Friday morning with the bulk of pcpn on Friday and
Friday night.
Track of the developing surface low is still a little uncertain, as
GFS brings low across KY and EUR across northern AL. Pcpn to
gradually pull out on Saturday, and will be faster if EUR solution
is right.
Weak northern stream system to again move over Great Lakes on
Monday, but have kept forecast dry at this time, again due to the
differences in the models on track and moisture.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 525 PM CST TUE DEC 2 2014
MVFR with local IFR cigs continue over the forecast area early
this evening but the latest satellite imagery indicates clearing
taking place just west of the Mississippi River. Latest timing
has the backedge of the clouds at PIA and SPI between 02 and 03z
and at BMI and DEC around 04z...and finally over in CMI btwn
05z and 06z. The latest high resolution models have trended slower
with the clearing, especially across our eastern counties with
the RAP and HRRR suggesting clearing over the CMI TAF not occurring
until after 09z. For now will go with continuity based on the present
movement of the clouds to the east with all of our area seeing VFR
conditions by late tonight which will continue through Wednesday.
Surface winds will be southwest at around 10 kts tonight and then
switch into a west to northwest direction mid-morning Wednesday
as a weak frontal boundary shifts across the area. Speeds during
the day will average from 10 to 15 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Smith
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1105 PM EST TUE DEC 2 2014
.UPDATE...
ISSUED AT 1105 PM EST TUE DEC 2 2014
DID A QUICK UPDATE TO REFINE THE FORECAST T/TD GRIDS THROUGH THE REST
OF THE NIGHT. DID ALSO LOOK AHEAD TO WEDNESDAY NIGHT AND DECIDED TO
NIX THE IDEA OF SNOW BASED ON SOUNDINGS AND LOWER POPS. UPDATED THE
ZONES AND HWO TO REMOVE THIS MENTION. THE REST OF THE FORECAST IS ON
TRACK WITH THE FOG AND DRIZZLE THROUGH THE NIGHT FOR MUCH OF THE
AREA. UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 820 PM EST TUE DEC 2 2014
00Z SFC ANALYSIS SHOWS A COLD FRONT BISECTING EASTERN KENTUCKY FROM
SOUTHWEST TO NORTHEAST. ALONG THIS BOUNDARY LIGHT RAIN AND PATCHY
DRIZZLE IS AFFECTING MUCH OF FAR EASTERN KENTUCKY. TO THE EAST OF THE
FRONT TEMPERATURES ARE IN THE 50S WHILE 40S ARE FOUND TO THE WEST
ALONG WITH AREAS OF FOG. THIS FOG IS LOCALLY DENSE...PARTICULARLY ON
THE RIDGETOPS. HAVE UPDATED THE FORECAST TO REFLECT THE POPS AND WX
ALONG THE FRONT...BASED ON THE CURRENT TRENDS AND THE LATEST GUIDANCE
FROM THE HRRR AND NAM12. ALSO ADDED FOG TO THE GRIDS TO THE NORTHWEST
OF THE FRONT ALONG WITH SOME DENSE PATCHES ON THE RIDGES. ALSO
TWEAKED HOURLY TEMPS AND DEWPOINTS THROUGH THE NIGHT PER THE LATEST
OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE HAVE BEEN SENT TO THE
NDFD AND WEB SERVERS ALONG WITH AN SPS FOR THE FOG FOR OUR NORTHERN
AND WESTERN HALF OF THE CWA AND AN UPDATED SET OF ZONES AND HWO.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 314 PM EST TUE DEC 2 2014
PRECIPITATION WILL CONTINUE TO WIND DOWN ACROSS EASTERN KENTUCKY
THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING HOURS. BASED
ON CURRENT RADAR TRENDS AND THE LATEST SHORT TERM MODEL DATA...WE
SHOULD SEE A SHORT BREAK IN THE RAIN. THE BREAK WILL BE SHORT
LIVED...HOWEVER...AS ANOTHER WAVE OF LOW PRESSURE IS ALREADY MOVING
OUT OF THE SOUTHERN PLAINS AND ALONG A STALLED OUT FRONTAL BOUNDARY
THAT CURRENTLY STRETCHES DOWN TO THE WESTERN GULF OF MEXICO THEN BACK
NORTHWARD ACROSS THE TEXAS AND OKLAHOMA PAN HANDLE REGIONS. THIS
WAVE IS PROGGED TO BRING PRECIP BACK TO THE AREA BETWEEN 1 AND 3Z
THIS EVENING. IF THE WAVE HOLDS ON ITS FORECAST TRACK...THE BULK OF
RAIN WILL OCCUR IN OUR EASTERN TWO OR THREE TIERS OF COUNTIES
OVERNIGHT. THE SLUGGISH FRONT WILL CONTINUE TO ACT AS A TRIGGER FOR
RAIN SHOWERS THROUGH WEDNESDAY AFTERNOON. THIS SECOND ROUND OF RAIN
SHOULD BE COMING TO END LATE WEDNESDAY. THERE IS A SMALL CHANCE THAT
A FEW RAIN OR SNOW SHOWERS COULD DEVELOP NORTH OF AN APPROACHING WARM
FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...BUT THE MODELS ARE NOT
IN THE BEST AGREEMENT AS TO WHETHER THIS WILL HAPPEN OR NOT. THAT
BEING SAID...DECIDED TO INCLUDE ONLY A SLIGHT CHANCE OF PRECIPITATION
RIGHT AT THE END OF THE SHORT TERM PERIOD. THE TEMPERATURE CURVE FOR
THAT TIME FRAME WOULD ALLOW FOR A MIX OF RAIN AND SNOW SHOULD THERE
BE ENOUGH MOISTURE AND LIFT FOR PRECIPITATION TO FORM. TEMPERATURES
THROUGHOUT THE SHORT TERM PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL FOR TOMORROWS HIGHS AND ABOVE NORMAL TONIGHT FOR THE LOWS.
OVERNIGHT LOWS ON WEDNESDAY LOOK TO BE RIGHT ABOUT NORMAL FOR THE
TIME OF YEAR...WITH SLIGHTLY BELOW NORMAL READINGS POSSIBLE NORTH OF
THE MOUNTAIN PARKWAY...AND RIGHT AT NORMAL SOUTH OF THERE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 PM EST TUE DEC 2 2014
AT UPPER LEVELS... MODELS ARE IN FAIRLY GOOD AGREEMENT OVERALL...
WITH THE 500MB FLOW REMAINING ZONAL THROUGH THE END OF THE WORK
WEEK. THE UPPER LEVEL FLOW PATTERN THEN TRANSITIONS INTO A RIDGE
TROUGH SPLIT OVER THE WESTERN/EASTERN CONUS BY THE FIRST PART OF
NEXT WEEK. THE TRANSITION PERIOD BETWEEN THESE TWO FLOW PATTERNS IS
WHERE MOST OF THE MODEL DIFFERENCES APPEAR TO BE...WITH THE ECMWF
STRENGTHENING AND OR AMPLIFYING THE SOUTHERN STREAM ENERGY AS IT
CROSSES THE CONUS AND THE GFS BEING A BIT MORE PROGRESSIVE.
THOUGH...THE GFS AND CANADIAN MODELS HAVE TRENDED TOWARDS THE ECMWF
SOLUTION TODAY COMPARED TO YESTERDAYS RUNS.
THE UPPER LEVEL FLOW PATTERN TRANSLATES INTO A FAIRLY WET PERIOD AT
THE SFC FOR EASTERN KENTUCKY...WITH THE ONLY EXCEPTION BEING THE
VERY BEGINNING AND END OF THE EXTENDED PERIOD. EARLY THURSDAY MORNING
THERE IS HIGH PRESSURE PROVIDING SOME SUBSIDENCE AND DRYING TO THE
REGION. HOWEVER THIS BREAK FROM PRECIP IS SHORT LIVED AS THE HIGH
QUICKLY PUSHES EWD AND SOUTHERLY LOW-TO-MID LEVEL FLOW USHERS IN
MOISTURE FROM THE GULF. RAIN CHANCES INCREASE AGAIN INTO THE WEEKEND
AS A LOW THAT EJECTED OUT OF THE ROCKIES MAKES ITS WAY INTO OUR
REGION. THE BULK OF THE RAIN FROM THIS SYSTEM WILL LIKELY BE ON
SATURDAY BUT MODELS SHOW SOME LINGERING RAIN SHOWERS THROUGH SUNDAY
AS WELL. FOR THE END OF THE OUTLOOK PERIOD THE REGION WILL GET A
BREAK FROM THE RAIN AS MONDAY/TUESDAY LOOKS TO BE FAIRLY DRY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 730 PM EST TUE DEC 2 2014
BASED ON TRENDS IN THE OBSERVATIONS AND THE LATEST MODEL DATA...IT
APPEARS LIKELY THAT THE TAF SITES WILL SPEND A GOOD AMOUNT OF TIME IN
THE LIFR OR VLIFR RANGE GIVEN THE HIGH MOISTURE CONTENT IN PLACE.
EXPECT THE CIGS AND VIS TO REBOUND LATE TONIGHT AND CONTINUE TO
IMPROVE INTO MVFR RANGE BY MIDDAY WEDNESDAY. WINDS WILL BE GENERALLY
LIGHT AND VARIABLE THROUGH THE NIGHT AND THEN PICK UP A NOTCH FROM
THE SOUTHWEST INTO MIDDAY WEDNESDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...AR
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
820 PM EST TUE DEC 2 2014
.UPDATE...
ISSUED AT 820 PM EST TUE DEC 2 2014
00Z SFC ANALYSIS SHOWS A COLD FRONT BISECTING EASTERN KENTUCKY FROM
SOUTHWEST TO NORTHEAST. ALONG THIS BOUNDARY LIGHT RAIN AND PATCHY
DRIZZLE IS AFFECTING MUCH OF FAR EASTERN KENTUCKY. TO THE EAST OF THE
FRONT TEMPERATURES ARE IN THE 50S WHILE 40S ARE FOUND TO THE WEST
ALONG WITH AREAS OF FOG. THIS FOG IS LOCALLY DENSE...PARTICULARLY ON
THE RIDGETOPS. HAVE UPDATED THE FORECAST TO REFLECT THE POPS AND WX
ALONG THE FRONT...BASED ON THE CURRENT TRENDS AND THE LATEST GUIDANCE
FROM THE HRRR AND NAM12. ALSO ADDED FOG TO THE GRIDS TO THE NORTHWEST
OF THE FRONT ALONG WITH SOME DENSE PATCHES ON THE RIDGES. ALSO
TWEAKED HOURLY TEMPS AND DEWPOINTS THROUGH THE NIGHT PER THE LATEST
OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE HAVE BEEN SENT TO THE
NDFD AND WEB SERVERS ALONG WITH AN SPS FOR THE FOG FOR OUR NORTHERN
AND WESTERN HALF OF THE CWA AND AN UPDATED SET OF ZONES AND HWO.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 314 PM EST TUE DEC 2 2014
PRECIPITATION WILL CONTINUE TO WIND DOWN ACROSS EASTERN KENTUCKY
THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING HOURS. BASED
ON CURRENT RADAR TRENDS AND THE LATEST SHORT TERM MODEL DATA...WE
SHOULD SEE A SHORT BREAK IN THE RAIN. THE BREAK WILL BE SHORT
LIVED...HOWEVER...AS ANOTHER WAVE OF LOW PRESSURE IS ALREADY MOVING
OUT OF THE SOUTHERN PLAINS AND ALONG A STALLED OUT FRONTAL BOUNDARY
THAT CURRENTLY STRETCHES DOWN TO THE WESTERN GULF OF MEXICO THEN BACK
NORTHWARD ACROSS THE TEXAS AND OKLAHOMA PAN HANDLE REGIONS. THIS
WAVE IS PROGGED TO BRING PRECIP BACK TO THE AREA BETWEEN 1 AND 3Z
THIS EVENING. IF THE WAVE HOLDS ON ITS FORECAST TRACK...THE BULK OF
RAIN WILL OCCUR IN OUR EASTERN TWO OR THREE TIERS OF COUNTIES
OVERNIGHT. THE SLUGGISH FRONT WILL CONTINUE TO ACT AS A TRIGGER FOR
RAIN SHOWERS THROUGH WEDNESDAY AFTERNOON. THIS SECOND ROUND OF RAIN
SHOULD BE COMING TO END LATE WEDNESDAY. THERE IS A SMALL CHANCE THAT
A FEW RAIN OR SNOW SHOWERS COULD DEVELOP NORTH OF AN APPROACHING WARM
FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...BUT THE MODELS ARE NOT
IN THE BEST AGREEMENT AS TO WHETHER THIS WILL HAPPEN OR NOT. THAT
BEING SAID...DECIDED TO INCLUDE ONLY A SLIGHT CHANCE OF PRECIPITATION
RIGHT AT THE END OF THE SHORT TERM PERIOD. THE TEMPERATURE CURVE FOR
THAT TIME FRAME WOULD ALLOW FOR A MIX OF RAIN AND SNOW SHOULD THERE
BE ENOUGH MOISTURE AND LIFT FOR PRECIPITATION TO FORM. TEMPERATURES
THROUGHOUT THE SHORT TERM PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL FOR TOMORROWS HIGHS AND ABOVE NORMAL TONIGHT FOR THE LOWS.
OVERNIGHT LOWS ON WEDNESDAY LOOK TO BE RIGHT ABOUT NORMAL FOR THE
TIME OF YEAR...WITH SLIGHTLY BELOW NORMAL READINGS POSSIBLE NORTH OF
THE MOUNTAIN PARKWAY...AND RIGHT AT NORMAL SOUTH OF THERE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 PM EST TUE DEC 2 2014
AT UPPER LEVELS... MODELS ARE IN FAIRLY GOOD AGREEMENT OVERALL...
WITH THE 500MB FLOW REMAINING ZONAL THROUGH THE END OF THE WORK
WEEK. THE UPPER LEVEL FLOW PATTERN THEN TRANSITIONS INTO A RIDGE
TROUGH SPLIT OVER THE WESTERN/EASTERN CONUS BY THE FIRST PART OF
NEXT WEEK. THE TRANSITION PERIOD BETWEEN THESE TWO FLOW PATTERNS IS
WHERE MOST OF THE MODEL DIFFERENCES APPEAR TO BE...WITH THE ECMWF
STRENGTHENING AND OR AMPLIFYING THE SOUTHERN STREAM ENERGY AS IT
CROSSES THE CONUS AND THE GFS BEING A BIT MORE PROGRESSIVE.
THOUGH...THE GFS AND CANADIAN MODELS HAVE TRENDED TOWARDS THE ECMWF
SOLUTION TODAY COMPARED TO YESTERDAYS RUNS.
THE UPPER LEVEL FLOW PATTERN TRANSLATES INTO A FAIRLY WET PERIOD AT
THE SFC FOR EASTERN KENTUCKY...WITH THE ONLY EXCEPTION BEING THE
VERY BEGINNING AND END OF THE EXTENDED PERIOD. EARLY THURSDAY MORNING
THERE IS HIGH PRESSURE PROVIDING SOME SUBSIDENCE AND DRYING TO THE
REGION. HOWEVER THIS BREAK FROM PRECIP IS SHORT LIVED AS THE HIGH
QUICKLY PUSHES EWD AND SOUTHERLY LOW-TO-MID LEVEL FLOW USHERS IN
MOISTURE FROM THE GULF. RAIN CHANCES INCREASE AGAIN INTO THE WEEKEND
AS A LOW THAT EJECTED OUT OF THE ROCKIES MAKES ITS WAY INTO OUR
REGION. THE BULK OF THE RAIN FROM THIS SYSTEM WILL LIKELY BE ON
SATURDAY BUT MODELS SHOW SOME LINGERING RAIN SHOWERS THROUGH SUNDAY
AS WELL. FOR THE END OF THE OUTLOOK PERIOD THE REGION WILL GET A
BREAK FROM THE RAIN AS MONDAY/TUESDAY LOOKS TO BE FAIRLY DRY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 730 PM EST TUE DEC 2 2014
BASED ON TRENDS IN THE OBSERVATIONS AND THE LATEST MODEL DATA...IT
APPEARS LIKELY THAT THE TAF SITES WILL SPEND A GOOD AMOUNT OF TIME IN
THE LIFR OR VLIFR RANGE GIVEN THE HIGH MOISTURE CONTENT IN PLACE.
EXPECT THE CIGS AND VIS TO REBOUND LATE TONIGHT AND CONTINUE TO
IMPROVE INTO MVFR RANGE BY MIDDAY WEDNESDAY. WINDS WILL BE GENERALLY
LIGHT AND VARIABLE THROUGH THE NIGHT AND THEN PICK UP A NOTCH FROM
THE SOUTHWEST INTO MIDDAY WEDNESDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...AR
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS PADUCAH KY
303 PM CST Mon Dec 1 2014
.SHORT TERM...(Tonight through Wednesday night)
Issued at 253 PM CST MON DEC 1 2014
The light precipitation activity continues to diminish across the
region. Evidence per the RAP and Wvapor imagery of a h7/h5 wave
still to our west. It`s rather weak. But there may be just enough
lift with the residual moisture, to result in some very light
precip through the evening. Both the NAM and RAP pick up on this
minimal QPF. The freezing line is expected to move little through
the night. So issued a Special Weather Statement for portions of
southeast MO, southern IL through the evening, for the potential
for spotty very light freezing rain/drizzle. Overnight, PoPs
diminish. Dry weather Tuesday through most of Wednesday. Chance of
light rain very late in the day working into southeast MO. The
chances will increase from SW to NE Wednesday night. Later in the
night through early Thursday morning, may see a light mix across
northern portions of the area. Temps were a blend of MOS, existing
numbers and base model output.
.LONG TERM...(Thursday through Sunday)
Issued at 303 PM CST MON DEC 1 2014
The GFS/ECMWF ensemble means were in general agreement on the
longwave pattern over the CONUS at this time, except on Mon (Day 7)
where the picture is a bit murkier in the swrn CONUS. We will be
lucky to see the sun in the wrn half of the area on Sat.
The finer details of the shrtwv activity were more uncertain among
the med range models, as they have had some trouble locking onto the
Pacific Express.
The extended forecast will start out with the lingering influence of
cold high sfc pressure for the PAH forecast area. By 12z Thu, model
soundings show the nrn half of the region may receive some light
freezing rain, changing to rain by mid morning. Sleet is possible.
The srn half will have rain. This should occur as moist flow aloft
begins to ride over the cooler air at the sfc.
The forecast will be very wet starting Thu night as a frontal
boundary sets up west to east somewhere across the PAH forecast
area, along with a developing wave of low pressure. The boundary is
forecast to move sewd on late on Fri in response to another shrtwv.
The best PoPs will be in the srn half of the region. Rain should
start to diminish from the nw Fri night as the system moves off, and
the region should be rain-free by Sat night under some degree of
ridging.
The ECMWF and GFS operational 12Z runs have different degrees of mid
level ridging over the weekend, and therefore the flatter GFS has
yet another shrtwv moving in from the west significantly quicker
than the ECMWF/UKMET and possibly the GEM. Therefore, what the
initialization blend provided was tamped down a bit as far as the
onset of rainfall. At this time, mainly areas west of the MS River
will have PoPs Sun. Due to model disagreement, limited chances of
rain were left in for Sun night and Mon. For now, thunder was left
out of the forecast, though it is not entirely impossible near the
low pressure wave Fri.
Expect temps to remain relatively mild through the extended period,
close to average for this time of year.
&&
.AVIATION...
Issued at 1134 AM CST MON DEC 1 2014
Band of precip was from KEVV to KPAH into SEMO, but diminishing from
west to east across southern IL into SEMO. Will maintain all liquid
-RADZ type wording at KPAH, KEVV and KOWB early this afternoon. Some
light freezing precip may persist at KCGI and across portions of
southern IL into southeast MO, as a mid level disturbance moves in
from the west, and across the region late today and early evening.
Some drying working in from the north may allow bases to rise at
KEVV and maybe even KCGI. This should transition back to lower cigs
tonight as the short range output and assoc Skew-Ts show lowering
bases tonight well within MVFR and possibly at or just into IFR
late. This is a downward trend from the inherited forecast. Do not
have VSBY restrictions in at this time given potential temp/dew
point spreads. Will monitor.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
LONG TERM...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
253 PM CST Mon Dec 1 2014
.SHORT TERM...(Tonight through Wednesday night)
Issued at 253 PM CST MON DEC 1 2014
The light precipitation activity continues to diminish across the
region. Evidence per the RAP and Wvapor imagery of a h7/h5 wave
still to our west. It`s rather weak. But there may be just enough
lift with the residual moisture, to result in some very light
precip through the evening. Both the NAM and RAP pick up on this
minimal QPF. The freezing line is expected to move little through
the night. So issued a Special Weather Statement for portions of
southeast MO, southern IL through the evening, for the potential
for spotty very light freezing rain/drizzle. Overnight, PoPs
diminish. Dry weather Tuesday through most of Wednesday. Chance of
light rain very late in the day working into southeast MO. The
chances will increase from SW to NE Wednesday night. Later in the
night through early Thursday morning, may see a light mix across
northern portions of the area. Temps were a blend of MOS, existing
numbers and base model output.
.LONG TERM...(Thursday through Sunday)
Issued at 320 AM CST MON DEC 1 2014
A moist westerly Pacific flow in the upper levels of the atmosphere
will keep precip chances in the forecast through most of the long
term period. As far as the specific track and timing of systems
within this flow, the models are in less agreement than 24 hours
ago. Will broad-brush chance pops through the period.
As far as the daily details...
On Wednesday night, a cold surface high pressure system will be
located over the upper Mississippi Valley. The models have trended
stronger with this high, which has resulted in lower pops and colder
temps over our area. The first in a series of mid-level shortwaves
will approach from the west. Any precip that manages to reach the
ground could begin as a little freezing rain north of a kcgi/kmdh
line. Pops in that area will be only in the slight chance category
however.
On Thursday and Thursday night, the aforementioned shortwave will
produce some rain over portions of the area. The models differ on
the track and timing of this shortwave, which seems easiest to
locate at the 700 mb level. A relatively warm and moist southwest
flow at 850 mb will overrun a cool northeast surface flow. This
should contribute to precip coverage. Pops will be kept in the
chance category due to model differences in the track of the
shortwave.
On Friday and Friday night, the models indicate a very moist Pacific
shortwave of subtropical origin will track from northern Mexico
across the lower and mid Mississippi Valley. The heaviest qpf and
best moisture with this system is shown from southern Missouri and
southern Kentucky southward. Pops will be in the likely category
across se Missouri and sw Kentucky, with chance pops to the north.
The 00z ecmwf appears to be an outlier with its stronger surface low
passing across northern Arkansas Friday. Will follow the gfs and
gefs consensus, which keeps a relatively cool east to southeast
surface wind over our region.
On Saturday and Saturday night, a short period of mainly dry weather
is still expected in the wake of the shortwave passage. The models
have shown decent consistency with this drying trend Saturday.
However, this will not be the end of the shortwave train as another
Pacific system will be waiting in the wings for Sunday or Sunday
night. The very persistent surface high over the Great Lakes is
forecast to move east, which should allow surface winds to become
more southeast to south by late in the weekend.
&&
.AVIATION...
Issued at 1134 AM CST MON DEC 1 2014
Band of precip was from KEVV to KPAH into SEMO, but diminishing from
west to east across southern IL into SEMO. Will maintain all liquid
-RADZ type wording at KPAH, KEVV and KOWB early this afternoon. Some
light freezing precip may persist at KCGI and across portions of
southern IL into southeast MO, as a mid level disturbance moves in
from the west, and across the region late today and early evening.
Some drying working in from the north may allow bases to rise at
KEVV and maybe even KCGI. This should transition back to lower cigs
tonight as the short range output and assoc Skew-Ts show lowering
bases tonight well within MVFR and possibly at or just into IFR
late. This is a downward trend from the inherited forecast. Do not
have VSBY restrictions in at this time given potential temp/dew
point spreads. Will monitor.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
1217 PM EST MON DEC 1 2014
.UPDATE...
ISSUED AT 943 AM EST MON DEC 1 2014
A FEW AREAS OF RAIN HAVE BEEN DEVELOPING OVER THE SOUTHERN PART OF
THE FORECAST AREA AND OVER NORTHERN TN. AS SUCH HAVE ADDED A SLIGHT
CHANCE OF RAIN IN THE SOUTH FOR THIS MORNING TO ACCOUNT FOR THIS. THE
MAIN AREA OF RAIN WILL STILL BE SLOW TO REACH THE SOUTHERN PART OF
THE FORECAST AREA. NDFD AND ZFP HAVE BEEN UPDATED.
UPDATE ISSUED AT 639 AM EST MON DEC 1 2014
THE COLD FRONT IS BASICALLY PERFORMING AS FORECAST STRETCHING FROM
LEX TO IOB TO SYM AT THE PRESENT TIME. HOWEVER...THE PROGRESSION OF
THE RAIN TO THE SOUTH IS SLIGHTLY SLOWER THAN PREVIOUSLY THOUGHT AND
THE LATEST HRRR RUNS ARE REALLY SLOW IN BREAKING OUT RAIN OVER OUR
SOUTHEAST COUNTIES. SO...FINE TUNED THE HOURLY POP GRIDS TO SLOW DOWN
THE SOUTHWARD PUSH A FEW HOURS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 316 AM EST MON DEC 1 2014
THE COLD FRONT IS ON OUR DOORSTEP AT 3 AM HAVING JUST NOW PASSED THE
MAYSVILLE MESONET STATION. THIS WILL PROGRESS STEADILY THROUGH OUR
AREA THIS MORNING EXITING INTO VIRGINIA BY LATE AFTERNOON. RAIN
SHOWERS CONTINUE TO BLOSSOM ALONG AND BEHIND THE FRONT. THESE WILL
PROGRESS SLOWLY SOUTHEAST INTO OUR NORTHERN COUNTIES OVER THE NEXT
FEW HOURS. THE RAIN MAY DIMINISH SOME LATER IN THE MORNING AS IT
WORKS INTO THE HEART OF EAST KENTUCKY...BUT AN UPSTREAM SHORTWAVE
SHOULD CAUSE IT TO EXPAND AGAIN LATE IN THE DAY AND INTO THE EVENING
HOURS. THE OTHER IMPACTS BROUGHT BY THE PASSAGE OF THE FRONT WILL BE
A QUICK SHIFT IN WINDS TO THE NORTHWEST...AND FALLING TEMPS. EARLY
HIGHS AROUND 60 WILL END UP RANGING FROM THE UPPER 30S ALONG I-64 TO
THE UPPER 40S ALONG THE VIRGINIA BORDER BY EARLY EVENING.
THE OTHER CONCERN HAS BEEN THE THREAT FOR A BIT OF WINTRY PRECIP
TONIGHT NORTH OF I-64. WHILE WE CANNOT RULE OUT A LITTLE
INCONSEQUENTIAL SLEET DURING THE EVENING...WE DID NOT MENTION THIS
IN THE FORECAST. WE DID KEEP A SLIGHT CHANCE OF FREEZING RAIN IN THE
FORECAST NORTH OF I-64 LATE IN THE NIGHT AND EARLY TUESDAY MORNING
AS THERE MAY BE A FEW POCKETS DROP TO FREEZING THERE. IF THE
FREEZING PRECIP DOES OCCUR...ROAD TEMPS WOULD LIKELY NOT GET COLD
ENOUGH FOR ANY WORRIES.
ON TUESDAY...THE 850 MB FLOW RAMPS UP OVER THE STATE AND BACKS TO
THE SOUTHWEST IN RESPONSE TO A SHORTWAVE DIVING INTO THE NORTHERN
PLAINS. THIS WILL BEGIN TO PUSH THE SURFACE BOUNDARY BACK TO THE
NORTH WITH TEMPERATURES OVER OUR SOUTHEAST COUNTIES WARMING WELL
INTO THE 50S...WHILE OUR NORTHERN COUNTIES STRUGGLE TO REACH THE
40S. A LITTLE OVERRUNNING LIGHT RAIN AND DRIZZLE CAN BE EXPECTED
THROUGHOUT THE DAY AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 316 AM EST MON DEC 1 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AND
INTO THE UPCOMING WEEKEND. WHILE DIFFERENCES ARE EVIDENT IN THE
MODELS...ONE THING THEY DO AGREE ON IS KEEPING A STALLED BOUNDARY
ACROSS THE AREA INTO THURSDAY...AND KEEPING THE WEATHER UNSETTLED
INTO SATURDAY. THIS WILL KEEP A FAIRLY GOOD TEMPERATURE/DEWPOINT
GRADIENT ACROSS THE AREA FOR SEVERAL DAYS. THUS...TEMPERATURE
FORECAST IS HIGHLY DEPENDENT WHERE THAT FRONT IS AT ANYTIME BETWEEN
NOW AND THE WEEKEND AND WILL FEATURE PLENTY OF ROOM FOR TEMPERATURE
TO GO UP OR DOWN FROM THE CURRENT FORECAST. IN THIS SCENARIO...A
BLENDED FORECAST IS CERTAINLY A GOOD WAY TO GO...AND STAY AWAY FROM
THE EXTREME HIGHS AND LOWS FOR NOW. CLOUD COVER WILL HANG TOUGH
RIGHT THROUGH THE END OF THE WEEK WHICH WILL ALSO LIMIT THE DIURNAL
RANGE IN TEMPERATURES.
AS FAR AS RAIN CHANCES GO...WE MAY SEE SOME LIGHT RAIN/DRIZZLE HOLD
ON THROUGH TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS
SOUTHEAST KENTUCKY. A BRIEF PERIOD OF SUBSIDENCE MAY SHALLOW OUT THE
MOISTURE ENOUGH TO CUT OFF THE RAIN POTENTIAL FROM MIDDAY WEDNESDAY
INTO WEDNESDAY NIGHT. HOWEVER...A MID LEVEL SHORTWAVE WILL PUSH EAST
ON THURSDAY...BRINGING THE THREAT OF RAIN BACK INTO THE AREA. AT
THIS POINT...MODELS DIFFER QUITE A BIT ON HOW THINGS PLAY OUT INTO
THE UPCOMING WEEKEND...BUT REGARDLESS OF WHICH MODEL YOU BUY INTO...
IT WILL REMAIN DAMP WITH RAIN CHANCES CONTINUING INTO SATURDAY. IT
DOES LOOKS LIKE SOME POTENTIAL FOR US TO DRY OUT BY THE SECOND HALF
OF THE WEEKEND...SO WILL TREND POPS DOWNWARD BY THE END OF THE
PERIOD. AT THIS TIME...WHILE IT DOES LOOK DAMP INTO NEXT WEEKEND...
PRECIPITATION AMOUNTS SHOULD REMAIN OVERALL FAIRLY LIGHT THROUGH THE
PERIOD...WITH NO BIG SURGES OF HEAVY RAINFALL. THUS...IT DOES NOT
LOOK LIKE WE SHOULD HAVE MUCH FLOODING CONCERNS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1217 PM EST MON DEC 1 2014
AT 1715Z A COLD FRONT EXTENDS FROM JUST SOUTH OF SME TO JUST NORTH OF
LOZ TO JUST SOUTH OF JKL TO NEAR SJS. THE FRONT WILL BE SOUTH OF ALL
THE TAF SITES BY 18Z. AHEAD OF THE FRONT MVFR CEILINGS
PREVAIL...WHILE ON THE NORTH SIDE OF THE FRONT IFR CEILINGS ARE THE
RULE. THE FRONT WILL CONTINUE TO PRESS SOUTH AND MOVE OUT OF KENTUCKY
AND INTO TN AND VA BY EVENING. SOME AREAS OF LIGHT RAIN WILL OCCUR
ALONG AND AHEAD OF THE FRONT...BUT MOST OF THE RAIN IS WELL NORTH OF
THE FRONT...AND THIS WILL CONTINUE TO BE CASE THIS AFTERNOON AND
TONIGHT. AS THE FRONT SAGS FURTHER SOUTH CEILINGS WILL LOWER AND
WINDS WILL GRADUALLY GO FROM NORTH TO NORTHEAST. IFR CONDITIONS IN
LIGHT RAIN...WITH FOG AND LOW CEILINGS WILL PREVAIL TONIGHT. IFR
CEILINGS WILL PERSIST INTO THE DAY ON TUESDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...ABE
LONG TERM...KAS
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
943 AM EST MON DEC 1 2014
.UPDATE...
ISSUED AT 943 AM EST MON DEC 1 2014
A FEW AREAS OF RAIN HAVE BEEN DEVELOPING OVER THE SOUTHERN PART OF
THE FORECAST AREA AND OVER NORTHERN TN. AS SUCH HAVE ADDED A SLIGHT
CHANCE OF RAIN IN THE SOUTH FOR THIS MORNING TO ACCOUNT FOR THIS. THE
MAIN AREA OF RAIN WILL STILL BE SLOW TO REACH THE SOUTHERN PART OF
THE FORECAST AREA. NDFD AND ZFP HAVE BEEN UPDATED.
UPDATE ISSUED AT 639 AM EST MON DEC 1 2014
THE COLD FRONT IS BASICALLY PERFORMING AS FORECAST STRETCHING FROM
LEX TO IOB TO SYM AT THE PRESENT TIME. HOWEVER...THE PROGRESSION OF
THE RAIN TO THE SOUTH IS SLIGHTLY SLOWER THAN PREVIOUSLY THOUGHT AND
THE LATEST HRRR RUNS ARE REALLY SLOW IN BREAKING OUT RAIN OVER OUR
SOUTHEAST COUNTIES. SO...FINE TUNED THE HOURLY POP GRIDS TO SLOW DOWN
THE SOUTHWARD PUSH A FEW HOURS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 316 AM EST MON DEC 1 2014
THE COLD FRONT IS ON OUR DOORSTEP AT 3 AM HAVING JUST NOW PASSED THE
MAYSVILLE MESONET STATION. THIS WILL PROGRESS STEADILY THROUGH OUR
AREA THIS MORNING EXITING INTO VIRGINIA BY LATE AFTERNOON. RAIN
SHOWERS CONTINUE TO BLOSSOM ALONG AND BEHIND THE FRONT. THESE WILL
PROGRESS SLOWLY SOUTHEAST INTO OUR NORTHERN COUNTIES OVER THE NEXT
FEW HOURS. THE RAIN MAY DIMINISH SOME LATER IN THE MORNING AS IT
WORKS INTO THE HEART OF EAST KENTUCKY...BUT AN UPSTREAM SHORTWAVE
SHOULD CAUSE IT TO EXPAND AGAIN LATE IN THE DAY AND INTO THE EVENING
HOURS. THE OTHER IMPACTS BROUGHT BY THE PASSAGE OF THE FRONT WILL BE
A QUICK SHIFT IN WINDS TO THE NORTHWEST...AND FALLING TEMPS. EARLY
HIGHS AROUND 60 WILL END UP RANGING FROM THE UPPER 30S ALONG I-64 TO
THE UPPER 40S ALONG THE VIRGINIA BORDER BY EARLY EVENING.
THE OTHER CONCERN HAS BEEN THE THREAT FOR A BIT OF WINTRY PRECIP
TONIGHT NORTH OF I-64. WHILE WE CANNOT RULE OUT A LITTLE
INCONSEQUENTIAL SLEET DURING THE EVENING...WE DID NOT MENTION THIS
IN THE FORECAST. WE DID KEEP A SLIGHT CHANCE OF FREEZING RAIN IN THE
FORECAST NORTH OF I-64 LATE IN THE NIGHT AND EARLY TUESDAY MORNING
AS THERE MAY BE A FEW POCKETS DROP TO FREEZING THERE. IF THE
FREEZING PRECIP DOES OCCUR...ROAD TEMPS WOULD LIKELY NOT GET COLD
ENOUGH FOR ANY WORRIES.
ON TUESDAY...THE 850 MB FLOW RAMPS UP OVER THE STATE AND BACKS TO
THE SOUTHWEST IN RESPONSE TO A SHORTWAVE DIVING INTO THE NORTHERN
PLAINS. THIS WILL BEGIN TO PUSH THE SURFACE BOUNDARY BACK TO THE
NORTH WITH TEMPERATURES OVER OUR SOUTHEAST COUNTIES WARMING WELL
INTO THE 50S...WHILE OUR NORTHERN COUNTIES STRUGGLE TO REACH THE
40S. A LITTLE OVERRUNNING LIGHT RAIN AND DRIZZLE CAN BE EXPECTED
THROUGHOUT THE DAY AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 316 AM EST MON DEC 1 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AND
INTO THE UPCOMING WEEKEND. WHILE DIFFERENCES ARE EVIDENT IN THE
MODELS...ONE THING THEY DO AGREE ON IS KEEPING A STALLED BOUNDARY
ACROSS THE AREA INTO THURSDAY...AND KEEPING THE WEATHER UNSETTLED
INTO SATURDAY. THIS WILL KEEP A FAIRLY GOOD TEMPERATURE/DEWPOINT
GRADIENT ACROSS THE AREA FOR SEVERAL DAYS. THUS...TEMPERATURE
FORECAST IS HIGHLY DEPENDENT WHERE THAT FRONT IS AT ANYTIME BETWEEN
NOW AND THE WEEKEND AND WILL FEATURE PLENTY OF ROOM FOR TEMPERATURE
TO GO UP OR DOWN FROM THE CURRENT FORECAST. IN THIS SCENARIO...A
BLENDED FORECAST IS CERTAINLY A GOOD WAY TO GO...AND STAY AWAY FROM
THE EXTREME HIGHS AND LOWS FOR NOW. CLOUD COVER WILL HANG TOUGH
RIGHT THROUGH THE END OF THE WEEK WHICH WILL ALSO LIMIT THE DIURNAL
RANGE IN TEMPERATURES.
AS FAR AS RAIN CHANCES GO...WE MAY SEE SOME LIGHT RAIN/DRIZZLE HOLD
ON THROUGH TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS
SOUTHEAST KENTUCKY. A BRIEF PERIOD OF SUBSIDENCE MAY SHALLOW OUT THE
MOISTURE ENOUGH TO CUT OFF THE RAIN POTENTIAL FROM MIDDAY WEDNESDAY
INTO WEDNESDAY NIGHT. HOWEVER...A MID LEVEL SHORTWAVE WILL PUSH EAST
ON THURSDAY...BRINGING THE THREAT OF RAIN BACK INTO THE AREA. AT
THIS POINT...MODELS DIFFER QUITE A BIT ON HOW THINGS PLAY OUT INTO
THE UPCOMING WEEKEND...BUT REGARDLESS OF WHICH MODEL YOU BUY INTO...
IT WILL REMAIN DAMP WITH RAIN CHANCES CONTINUING INTO SATURDAY. IT
DOES LOOKS LIKE SOME POTENTIAL FOR US TO DRY OUT BY THE SECOND HALF
OF THE WEEKEND...SO WILL TREND POPS DOWNWARD BY THE END OF THE
PERIOD. AT THIS TIME...WHILE IT DOES LOOK DAMP INTO NEXT WEEKEND...
PRECIPITATION AMOUNTS SHOULD REMAIN OVERALL FAIRLY LIGHT THROUGH THE
PERIOD...WITH NO BIG SURGES OF HEAVY RAINFALL. THUS...IT DOES NOT
LOOK LIKE WE SHOULD HAVE MUCH FLOODING CONCERNS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 639 AM EST MON DEC 1 2014
EXPECT DETERIORATING CONDITIONS FROM NORTHWEST TO SOUTHEAST TODAY AS
A COLD FRONT PASSES THROUGH THE REGION. A BAND OF SHOWERS WILL
ACCOMPANY THE FRONT WITH A WIND SHIFT TO THE NORTHWEST AND THEN
NORTH. CEILINGS WILL DROP QUICKLY FROM VFR TO IFR BEHIND THE FRONT.
WE CURRENTLY FORECAST THE FRONTAL PASSAGE TO TAKE PLACE AT THE
FOLLOWING TIMES...
SYM...11Z SME...15Z JKL...15Z
LOZ...16Z SJS...16Z PBX...17Z
W38...18Z I35...20Z 1A6...20Z
AFTER THE FRONTAL PASSAGE...LOW CEILINGS AND LIGHT RAIN AND/OR
DRIZZLE WILL PERSIST AT THE TAF SITES THROUGH THE REMAINDER OF THE
PERIOD WITH WINDS CONTINUING TO VEER AROUND TO A NORTHEASTERLY
DIRECTION.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...ABE
LONG TERM...KAS
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
639 AM EST MON DEC 1 2014
.UPDATE...
ISSUED AT 639 AM EST MON DEC 1 2014
THE COLD FRONT IS BASICALLY PERFORMING AS FORECAST STRETCHING FROM
LEX TO IOB TO SYM AT THE PRESENT TIME. HOWEVER...THE PROGRESSION OF
THE RAIN TO THE SOUTH IS SLIGHTLY SLOWER THAN PREVIOUSLY THOUGHT AND
THE LATEST HRRR RUNS ARE REALLY SLOW IN BREAKING OUT RAIN OVER OUR
SOUTHEAST COUNTIES. SO...FINE TUNED THE HOURLY POP GRIDS TO SLOW DOWN
THE SOUTHWARD PUSH A FEW HOURS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 316 AM EST MON DEC 1 2014
THE COLD FRONT IS ON OUR DOORSTEP AT 3 AM HAVING JUST NOW PASSED THE
MAYSVILLE MESONET STATION. THIS WILL PROGRESS STEADILY THROUGH OUR
AREA THIS MORNING EXITING INTO VIRGINIA BY LATE AFTERNOON. RAIN
SHOWERS CONTINUE TO BLOSSOM ALONG AND BEHIND THE FRONT. THESE WILL
PROGRESS SLOWLY SOUTHEAST INTO OUR NORTHERN COUNTIES OVER THE NEXT
FEW HOURS. THE RAIN MAY DIMINISH SOME LATER IN THE MORNING AS IT
WORKS INTO THE HEART OF EAST KENTUCKY...BUT AN UPSTREAM SHORTWAVE
SHOULD CAUSE IT TO EXPAND AGAIN LATE IN THE DAY AND INTO THE EVENING
HOURS. THE OTHER IMPACTS BROUGHT BY THE PASSAGE OF THE FRONT WILL BE
A QUICK SHIFT IN WINDS TO THE NORTHWEST...AND FALLING TEMPS. EARLY
HIGHS AROUND 60 WILL END UP RANGING FROM THE UPPER 30S ALONG I-64 TO
THE UPPER 40S ALONG THE VIRGINIA BORDER BY EARLY EVENING.
THE OTHER CONCERN HAS BEEN THE THREAT FOR A BIT OF WINTRY PRECIP
TONIGHT NORTH OF I-64. WHILE WE CANNOT RULE OUT A LITTLE
INCONSEQUENTIAL SLEET DURING THE EVENING...WE DID NOT MENTION THIS
IN THE FORECAST. WE DID KEEP A SLIGHT CHANCE OF FREEZING RAIN IN THE
FORECAST NORTH OF I-64 LATE IN THE NIGHT AND EARLY TUESDAY MORNING
AS THERE MAY BE A FEW POCKETS DROP TO FREEZING THERE. IF THE
FREEZING PRECIP DOES OCCUR...ROAD TEMPS WOULD LIKELY NOT GET COLD
ENOUGH FOR ANY WORRIES.
ON TUESDAY...THE 850 MB FLOW RAMPS UP OVER THE STATE AND BACKS TO
THE SOUTHWEST IN RESPONSE TO A SHORTWAVE DIVING INTO THE NORTHERN
PLAINS. THIS WILL BEGIN TO PUSH THE SURFACE BOUNDARY BACK TO THE
NORTH WITH TEMPERATURES OVER OUR SOUTHEAST COUNTIES WARMING WELL
INTO THE 50S...WHILE OUR NORTHERN COUNTIES STRUGGLE TO REACH THE
40S. A LITTLE OVERRUNNING LIGHT RAIN AND DRIZZLE CAN BE EXPECTED
THROUGHOUT THE DAY AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 316 AM EST MON DEC 1 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AND
INTO THE UPCOMING WEEKEND. WHILE DIFFERENCES ARE EVIDENT IN THE
MODELS...ONE THING THEY DO AGREE ON IS KEEPING A STALLED BOUNDARY
ACROSS THE AREA INTO THURSDAY...AND KEEPING THE WEATHER UNSETTLED
INTO SATURDAY. THIS WILL KEEP A FAIRLY GOOD TEMPERATURE/DEWPOINT
GRADIENT ACROSS THE AREA FOR SEVERAL DAYS. THUS...TEMPERATURE
FORECAST IS HIGHLY DEPENDENT WHERE THAT FRONT IS AT ANYTIME BETWEEN
NOW AND THE WEEKEND AND WILL FEATURE PLENTY OF ROOM FOR TEMPERATURE
TO GO UP OR DOWN FROM THE CURRENT FORECAST. IN THIS SCENARIO...A
BLENDED FORECAST IS CERTAINLY A GOOD WAY TO GO...AND STAY AWAY FROM
THE EXTREME HIGHS AND LOWS FOR NOW. CLOUD COVER WILL HANG TOUGH
RIGHT THROUGH THE END OF THE WEEK WHICH WILL ALSO LIMIT THE DIURNAL
RANGE IN TEMPERATURES.
AS FAR AS RAIN CHANCES GO...WE MAY SEE SOME LIGHT RAIN/DRIZZLE HOLD
ON THROUGH TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS
SOUTHEAST KENTUCKY. A BRIEF PERIOD OF SUBSIDENCE MAY SHALLOW OUT THE
MOISTURE ENOUGH TO CUT OFF THE RAIN POTENTIAL FROM MIDDAY WEDNESDAY
INTO WEDNESDAY NIGHT. HOWEVER...A MID LEVEL SHORTWAVE WILL PUSH EAST
ON THURSDAY...BRINGING THE THREAT OF RAIN BACK INTO THE AREA. AT
THIS POINT...MODELS DIFFER QUITE A BIT ON HOW THINGS PLAY OUT INTO
THE UPCOMING WEEKEND...BUT REGARDLESS OF WHICH MODEL YOU BUY INTO...
IT WILL REMAIN DAMP WITH RAIN CHANCES CONTINUING INTO SATURDAY. IT
DOES LOOKS LIKE SOME POTENTIAL FOR US TO DRY OUT BY THE SECOND HALF
OF THE WEEKEND...SO WILL TREND POPS DOWNWARD BY THE END OF THE
PERIOD. AT THIS TIME...WHILE IT DOES LOOK DAMP INTO NEXT WEEKEND...
PRECIPITATION AMOUNTS SHOULD REMAIN OVERALL FAIRLY LIGHT THROUGH THE
PERIOD...WITH NO BIG SURGES OF HEAVY RAINFALL. THUS...IT DOES NOT
LOOK LIKE WE SHOULD HAVE MUCH FLOODING CONCERNS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 639 AM EST MON DEC 1 2014
EXPECT DETERIORATING CONDITIONS FROM NORTHWEST TO SOUTHEAST TODAY AS
A COLD FRONT PASSES THROUGH THE REGION. A BAND OF SHOWERS WILL
ACCOMPANY THE FRONT WITH A WIND SHIFT TO THE NORTHWEST AND THEN
NORTH. CEILINGS WILL DROP QUICKLY FROM VFR TO IFR BEHIND THE FRONT.
WE CURRENTLY FORECAST THE FRONTAL PASSAGE TO TAKE PLACE AT THE
FOLLOWING TIMES...
SYM...11Z SME...15Z JKL...15Z
LOZ...16Z SJS...16Z PBX...17Z
W38...18Z I35...20Z 1A6...20Z
AFTER THE FRONTAL PASSAGE...LOW CEILINGS AND LIGHT RAIN AND/OR
DRIZZLE WILL PERSIST AT THE TAF SITES THROUGH THE REMAINDER OF THE
PERIOD WITH WINDS CONTINUING TO VEER AROUND TO A NORTHEASTERLY
DIRECTION.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...ABE
LONG TERM...KAS
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1156 PM CST SUN NOV 30 2014
.AVIATION...
FOR THE 01/06Z TAFS...LOW CLOUDS WILL CONTINUE TO MOVE IN THE
REGION FROM THE WEST...BUT VFR CONDITIONS WILL REMAIN AT ALL SITES
THROUGH MOST OF THE OVERNIGHT PERIOD. CIGS AND VISIBILITIES WILL
LOWER NEAR DAYBREAK CREATING MVFR CONDITIONS AS A COLD FRONT
MOVES THROUGH THE AREA. SHWRS ARE POSSIBLE ALONG THE FRONT. WINDS
WILL REMAIN FROM THE SOUTH BETWEEN 5-10 KTS OVERNIGHT...BUT WILL
SHIFT TO THE NW FOLLOWING FRONTAL PASSAGE.
&&
.PREV DISCUSSION... /ISSUED 1001 PM CST SUN NOV 30 2014/
DISCUSSION...
SOME CHANGES WERE NECESSARY OVERNIGHT AS WELL AS MONDAY GIVEN A
SLIGHTLY FASTER FRONTAL MOVEMENT.
THE LEADING EDGE OF MUCH COLDER AIR IN THE FORM OF A STRONG COLD
FRONT WAS LOCATED NEAR A HRO...FSM...DUA...RPH LINE AS OF 03Z. A
20 TO 25 DEGREE TEMPERATURE DROP EXISTS DIRECTLY BEHIND THIS
BOUNDARY WHICH WAS OUTPACING OUR PREVIOUS FORECAST SLIGHTLY. THE
OUACHITAS WILL LIKELY SLOW THIS BOUNDARY UP SLIGHTLY BUT STILL
FEEL LIKE THE FASTER FRONTAL MOVEMENT VIA THE HRRR WARRANTED AN
UPDATE THIS EVENING. CLOUD COVER IS PATCHY ATTM BUT SHOULD
CONTINUE TO DEVELOP THROUGH THE OVERNIGHT HOURS AND THIS WILL BE
CRUCIAL AS IT PERTAINS TO OVERNIGHT LOW TEMPERATURES...NOT TO
MENTION JUST WHERE THE COLD FRONT IS EXPECTED TO BE BY 8 AM IN THE
MORNING. BY 13Z...EXPECT THE FRONT TO BE NEAR OR JUST EAST OF A
TYR...TO DEQ LINE...LIKELY BULGING OUT SLIGHTLY ACROSS THE
NORTHERN HALF OF NE TX GIVEN THE BLOCKING INFLUENCE OF THE
OUACHITAS.
WINDS HAVE DECOUPLED PRETTY MUCH AREAWIDE THIS EVENING...BUT
ESPECIALLY ACROSS OUR SE ZONES AND THIS IS WHERE PATCHY DENSE FOG
WILL BECOME A POSSIBILITY IF THE CLOUD COVER TAKES ITS TIME IN
FORMING. IF THIS FOG DEVELOPS...TEMPERATURES COULD FALL BELOW
THEIR DEWPOINTS WHICH ALSO MAKES THIS A CHALLENGING FORECAST AS IT
PERTAINS TO OVERNIGHT MIN TEMPS. RAISED TEMPERATURES SLIGHTLY
ALONG A LFK...SHV...ELD LINE BUT COOLED TEMPERATURES JUST WEST OF
THIS LINE AS THIS IS WHERE THE COLD FRONT IS EXPECTED TO BE BY 8
AM MON. COLD FRONT WILL LIKELY SLOW UP A BIT AS IT MOVES THROUGH
NORTHERN LA ON MONDAY BUT STILL FEEL LIKE MAX TEMPS WILL BE
REACHED DURING THE MORNING HOURS MONDAY GIVEN THE STRONG COLD AIR
ADVECTION BEHIND THE FRONT. HAVING SAID THIS...ALSO UPDATED HOURLY
DAYTIME TEMPERATURES TO BETTER REFLECT THE FALLING DAYTIME
TEMPERATURES.
DID NOT MAKE MUCH IN THE WAY OF CHANGES TO POP OVERNIGHT/MONDAY AS
THE HRRR IS IN GOOD AGREEMENT WITH SOME PREFRONTAL/FRONTAL AND POST
FRONTAL RAIN/SHOWERS DEVELOPING LATER TONIGHT AND THROUGH THE DAY
MONDAY.
UPDATED ZONE PACKAGE ALREADY SENT...13
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 61 63 38 52 47 / 20 60 30 0 10
MLU 60 73 40 53 45 / 20 60 40 10 10
DEQ 49 50 32 48 42 / 40 60 10 0 20
TXK 57 57 34 49 44 / 40 60 20 0 20
ELD 60 60 36 49 44 / 20 70 30 0 10
TYR 55 56 32 50 47 / 30 50 10 0 20
GGG 60 60 34 51 48 / 30 60 20 0 20
LFK 63 63 37 54 48 / 20 50 30 0 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
20
AREA FORECAST DISCUSSION
NWS CARIBOU ME
542 PM EST MON DEC 1 2014
.SYNOPSIS...
STRONG CANADIAN HIGH PRESSURE WILL APPROACH FROM THE WEST TONIGHT
AND WILL CROSS THE REGION TUESDAY. A WARM FRONT WILL APPROACH FROM
THE SOUTHWEST LATE TUESDAY NIGHT AND CROSS THE REGION BY LATE
WEDNESDAY. A NEW COLD FRONT WILL CROSS THE REGION THURSDAY.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
535 PM UPDATE...SATELLITE IR IMAGERY SHOWING A PLUME SETTING UP
OFF THE OPEN ST. LAWRENCE W/AN UPPER LEVEL DISTURBANCE MOVING INTO
THE REGION. THIS FEATURE IS PICKED UP WELL ON THE WATER VAPOR
IMAGERY AND BY THE LATEST RUN OF THE RAP MODEL. METARS AND WEBCAMS
SHOWING SOME LIGHT SNOW ACROSS NORTHERN MAINE INCLUDING THE ST.
JOHN VALLEY. THE DAYCREW DID A GOOD JOB IN PICKING THIS UP THROUGH
THIS EVENING. THE ONLY ADJUSTMENTS WAS TO MOVE AREA OF SNOW
FURTHER S TOWARD THE HOULTON REGION. A DUSTING OF SNOW IS
EXPECTED. HRLY TEMPERATURES NEEDED SOME ADJUSTMENT TO MATCH UP
W/THE LATEST OBS.
SKIES SHOULD CLR BY SUNRISE TUE FOR MOST LCTNS. WITH BRISK NW
WINDS...TEMPS OVRNGT AND ON TUE WILL BE MUCH COLDER...SPCLY CNTRL
AND DOWNEAST AREAS. UNDER MSLY SUNNY SKIES AND DECREASING WINDS...
HI TEMPS TUE WILL BE IN THE TEENS N TO LOWER TO MID 20S
DOWNEAST... ABOUT 20 TO 30 DEG LOWER THAN TDY. WINDS WILL DECREASE
TUE AFTN AS THE SFC HI AXIS CRESTS THE REGION.
TUE EVE WILL BEGIN MCLR TO PTLY CLDY...ALLOWING FOR SOME RADIATIONAL
COOLING...BUT TEMPS WILL LVL OUT TO ERLY LOWS BY OVRNGT AS HI
THIN CS CLD CVR THICKENS WITH THE APCH OF THE SFC LOW AND
ASSOCIATED S/WV ALF FROM THE GREAT LKS BEGINS TO APCH THE REGION.
OVRRNG PRECIP...MSLY INITIALLY IN THE FORM OF LGT SN...BEGINS TO
MOVE INTO THE REGION FROM WSW TO ENE LATE TUE NGT AS DEEP LOW TO
MID LVL S TO SE WINDS INCREASE. THIS WILL RESULT IN SIG RISES IN
TEMPS ACROSS THE REGION BY DAYBREAK WED...WITH 1 TO 2 INCHES OF
SNFL ACROSS THE REGION BY THIS TM.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
EXPECT OVERRUNNING PRECIPITATION TO BE ONGOING JUST ABOUT ACROSS
THE ENTIRE FORECAST AREA BY WEDNESDAY MORNING. WINTER WEATHER
ADVISORIES WILL BE NEEDED FOR MUCH OF THE REGION INTO WEDNESDAY AS
WARMER AIR ADVECTING IN ALOFT RESULTS IN A PERIOD OF MIXED
PRECIPITATION AND FREEZING RAIN JUST INLAND FROM THE IMMEDIATE
COAST. THE LOW LEVELS ARE EXPECTED TO WARM DURING WEDNESDAY WITH
MIXED PRECIPITATION AND FREEZING RAIN TRANSITIONING TO ALL RAIN
FROM SOUTH TO NORTH ACROSS MOST OF THE AREA BY WEDNESDAY
AFTERNOON. THE ONLY EXCEPTION WILL BE THE ST JOHN VALLEY WHERE
FREEZING PRECIPITATION MAY LINGER WELL INTO THE AFTERNOON HOURS. A
COLD FRONT WILL SWEEP ACROSS THE REGION WEDNESDAY EVENING WITH THE
CHANCE FOR SNOW SHOWERS PARTICULARLY ACROSS NORTHERN AND CENTRAL
AREAS WHERE WE COULD SEE AN INCH OR SO OF SNOW ACCUMULATION.
THURSDAY WILL TURN COLDER WITH A FEW SNOW SHOWERS POSSIBLE
THURSDAY MORNING ACROSS NORTHERN AREAS OTHERWISE IT WILL BE DRY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL BUILD OVER THE AREA THURSDAY NIGHT WITH CLEAR
AND VERY COLD CONDITIONS EXPECTED. LOWS THURSDAY NIGHT WILL FALL
TO AROUND ZERO WITH SOME SUB ZERO READINGS LIKELY IN THE NORMALLY
COLDER SHELTERED VALLEY LOCATIONS. FRIDAY WILL BE CONTINUED COLD
AND DRY AS HIGH PRESSURE SLIDES TO OUR EAST. THE FORECAST FOR THE
WEEKEND NOT QUITE CUT AND DRY AT THIS POINT WITH DIFFERENCES IN
MODEL SOLUTIONS. GFS SOLUTION SUGGESTS A COLD AND DRY WEEKEND AS
IT BUILDS HIGH PRESSURE ACROSS TO OUR NORTH. THE ECMWF BRINGS A
FRONT INTO THE AREA DURING SATURDAY WITH THE CHANCE OF
PRECIPITATION. STAYED WITH THE SUPERBLEND GUIDANCE WHICH BRINGS
LOW CHANCE OF PRECIPITATION SATURDAY AND SUNDAY. HIGH PRESSURE
WILL START TO BUILD BACK IN BY MONDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: A WINTRY MIX OF PRECIPITATION CAN BE EXPECTED AT THE
TERMINALS WEDNESDAY MORNING WITH THE EXCEPTION OF KBHB WHERE WE
SHOULD SEE ALL RAIN BY 12Z. THE FREEZING/FROZEN PRECIPITATION
SHOULD TRANSITION TO ALL RAIN ACROSS THE TERMINALS FROM SOUTH TO
NORTH DURING WEDNESDAY AFTERNOON WITH WIDESPREAD IFR/MVFR
EXPECTED ALL TERMINALS. MVFR CAN BE EXPECTED WEDNESDAY NIGHT IN
NORTHERN SHOW SHOWERS AND RAIN SHOWERS CHANGING TO SNOW SHOWERS.
VFR EXPECTED THURSDAY AND FRIDAY. VFR OR MVFR CONDITIONS LIKELY
SATURDAY.
SHORT TERM: MSLY VFR DOWNEAST SITES AND MVFR OR LOW VFR CLGS IN
BKN-OVC SC FOR NRN TAF SITES INTO THE OVRNGT...WITH BRIEF IFR
VSBYS POSSIBLE IN ISOLD SN SHWRS FOR NRN TAF SITES. ALL TAF SITES
THEN BECOME VFR BY DAYBREAK TUE AND CONT SO THRU TUE EVE. THEN
CLGS AND VSBYS LOWER WSW TO ENE WITH THE ARRIVAL OF LGT SN LATE
TUE NGT...XCPT LGT SN OR MIXED PRECIP FOR KBHB.
&&
.MARINE...
NEAR TERM: WILL CONT THE CURRENT SCA TNGT FOR MSLY WIND OVR THE
INNER BAY/HARBOR MZ052 AND FOR BOTH WINDS AND SEAS FOR OUTER
MZS050-051. AFTWRDS...WINDS AND SEAS SHOULD SUBSIDE BLO SCA
CRITERIA LATER TUE MORN AND CONT SO THRU TUE EVE. WINDS AND SEAS
BUILD BACK TO SCA OVR ALL OF OUR WATERS BY WED MORN AS SE WINDS
INCREASE ARND DEPARTING SFC HI PRES MOVG E OF THE CAN MARITIMES.
SHORT TERM: EXPECT SMALL CRAFT ADVISORY CONDITIONS WEDNESDAY
THROUGH THURSDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT/VJN
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/VJN/DUDA
MARINE...HEWITT/VJN/DUDA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
221 PM EST MON DEC 1 2014
.SYNOPSIS...
AN ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THE FIRST PART OF
THE WORK WEEK BEFORE HIGH PRESSURE SERVES UP A QUIET THURSDAY. YET
ANOTHER WEATHER SYSTEM TAKES AIM AT OUR REGION FRIDAY INTO
SATURDAY WITH THE POTENTIAL FOR A WINTRY MIX.
&&
.NEAR TERM /THROUGH TONIGHT/...
COLDER AIR ALOFT HAS MOVED INTO PARTS OF THE REGION AS DENOTED BY
LATEST RAP ANALYSIS WITH H8 TEMPS RANGING FROM 0C TO -4C N OF I-70
AS OF 18Z. WSR-88D KPBZ IS PICKING UP SLEET / LARGE SNOWFLAKE
MIXTURE NICELY IN THE DUAL POL CORRELATION COEFFICIENT FIELD AS
VALUES RANGE BETWEEN 0.9 AND 0.95. PRECIPITATION WILL END LATE THIS
AFTERNOON WITH LOCATIONS SOUTH OF THE MASON DIXON LINE BECOMING DRY
TOWARD MIDNIGHT GIVEN LINEAR EXTRAPOLATION OF RAIN OVER SOUTHWESTERN
OHIO...HOWEVER THAT BREAK WILL BE VERY BRIEF BEFORE NEXT SYSTEM
TAKES AIM.
AS HIGH PRESSURE PASSES TO OUR NORTH PLENTY OF MID AND UPPER LEVEL
MOISTURE RESIDES PREVENTING STRONG RADIATIONAL COOLING DESPITE
DEWPOINTS DROPPING BACK WELL INTO THE TEENS. OPTED FOR A WARMER
GUIDANCE SUITE KEEPING LOWER TO MID 20S OVER FAR NORTHERN SECTIONS
/NORTH OF I-80/. WHERE CLOUDS AND PRECIP LAST LONGER IN THE
SOUTHERN PART OF THE FORECAST AREA...LOWS WILL FALL BACK TO AROUND
30. CARRIED A WINTRY MIX OF SNOW AND SLEET WHERE POPS REMAIN THIS
EVENING. DO NOT SEE I-68 CORRIDOR GOING TO A WINTRY MIX UNTIL
AROUND 22Z-0Z GIVEN W TO E ORIENTATION OF THERMAL GRADIENT.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
LATEST 12Z OPERATIONAL NCEP RUNS CONTINUE THEME OF PREVIOUS DAY
SOLUTIONS ALONG WITH OFFSETTED HOURS OF SREF AND THEIR RESPECTIVE
ENSEMBLES OF A WINTRY MIX TUESDAY INTO WEDNESDAY MORNING. QPF VALUES
HAVE TRENDED NORTHWARD...HOWEVER LOOKING AT CROSS SECTIONS OF
UVV...MOISTURE...AND STABILITY HARD TO SEE THAT MUCH QPF OVER
GARRETT AND TUCKER. RECENT EVENTS AND THEIR HIGH BIAS ALSO SUPPORTS
LOWER LIQUID AMOUNTS THAN PROJECTED.
AS COLD AIR INFILTRATES THE REGION TONIGHT AND TRANSITORY SURFACE
ANTICYCLONE MOVES TO NEW ENGLAND...WARM LAYER ALOFT DEVELOPS IN
A COLD AIR DAMMING SETUP. AS ELUDED TOO IN MY PREVIOUS
DISCUSSIONS...AGEOSTROPHIC FLOW IS NOT THAT STRONG...HENCE ONLY A 40
KNOT BARRIER JET ALONG THE APPALACHIANS. IN SIGNIFICANT ICING
EVENTS...THIS FLOW WOULD BE NEARLY A FACTOR OF TWO HIGHER.
INHERITED FORECAST COVERS THIS AREA WELL WITH TIMING AND PCPN
CHANGE OVER. ALL LOCATIONS IN THE EASTERN PERIPHERY OF THE CWA
COULD SEE A PERIOD OF SNOW AND/OR SLEET AT THE ONSET BEFORE A
SWITCH OVER TO FZRA. BUFR SOUNDINGS SHOW MAX WARM LAYER ALOFT
TEMPERATURES CLIMBING BETWEEN 1C AND 3C ACROSS EASTERN PA ZONES AND
WITH OVERNIGHT TEMPS FALLING BACK WELL INTO THE 20S...A PERIOD OF
FZRA IS PREDICTED FROM FOREST CO SOUTH INTO EASTERN FAYETTE
COUNTY.
HOISTED A FREEZING RAIN ADVISORY IN COLLABORATION WITH WFO STATE
COLLEGE TUESDAY MORNING THROUGH DAYBREAK WEDNESDAY. ELECTED TO END
ADVISORY FOR EASTERN WESTMORELAND AND FAYETTE COUNTIES TUESDAY
NIGHT GIVEN BL FLOW SHOULD ERADICATE COLD AIR AT THE SFC EVEN
ACROSS THE DEEPER VALLEYS BETWEEN CHESTNUT AND LAUREL RIDGES.
FARTHER NORTH...CONFIDENCE IS HIGHER FOR COLD AIR TO STAY LOCKED
IN PLACE...WHICH FOLLOWS CLIMATOLOGICAL NORM. CLARION COUNTY WAS
THROWN IN...HOWEVER THEY SHOULD SWITCH OVER TO RAIN A FEW HOURS
SOONER THAN THEIR COUNTERPARTS TO THE NORTH /FOREST/ AND EAST
/JEFFERSON/.
ONE POSITIVE THING HEADING INTO THIS EVENT IS GIVEN THE RECENT
WARM WEATHER...THE GROUND WILL NOT BE AS COLD AS IT WAS FOR THE
ICING EVENT IN MID NOVEMBER. WE STILL DO NOT EXPECT A SIGNIFICANT
ICE STORM FOR ANY OF OUR COUNTIES. IF THE SOUTHEAST WINDS ARE
STRONG THAN EXPECTED...IT IS POSSIBLE THE GARRETT AND TUCKER COULD
SEE IN EXCESS OF A QUARTER OF AN INCH...BUT AFTER REVIEW OF PLUME
DIAGRAMS FOR 2G4 AND PIE SIDED WITH THE MEAN OF THE PAST FEW RUNS
WHICH PLACES STORM TOTAL ICE ACCUMULATION AROUND 0.15 TO 0.20
INCHES. A QUARTER OF AN INCH OF ICE IS NEEDED FOR AN ICE STORM
WARNING.
TEMPERATURES WERE A BLEND OF THE ONGOING FORECAST AND THE ADJMET
BIAS CORRECTED GRIDS. A GRADUAL WARM UP TO SEASONAL NUMBER IN THE
LOWER TO MID 40S IS SLATED FOR MID WEEK.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
MOISTURE ERODES FROM THE TOP DOWN WEDS AS SFC HIGH PRESSURE TRIES
TO NOSE IN FROM THE WEST. MOISTURE TRAPPED UNDER THE H85 INVERSION
WILL KEEP POP CHCS IN THROUGH EARLY THURS...BUT MAY OCCUR MORE IN
THE FORM OF LIGHT DRIZZLE THAN ANYTHING ELSE. MOISTURE IS FINALLY
SCOURED OUT COMPLETELY THURS FOR WHAT SHOULD BE THE DRIEST DAY OF
THE WORK WEEK BEFORE THE NEXT SYSTEM BEGINS TO ENCROACH FROM THE
SOUTH. A BOUNDARY WILL ONCE AGAIN SET UP NEAR OR JUST SOUTH OF THE
AREA EARLY FRI...WITH WEAK WAVES MOVING ALONG IT. COLD AIR IN
PLACE AHEAD OF THE MOISTURE COULD RESULT IN ANOTHER ROUND OF
WINTRY MIX AND POSSIBLY SOME FREEZING RAIN. WITH THIS BEING DAY
4...TRIED TO KEEP DETAILS GENERAL...AND WILL NEED FURTHER ROUNDS
OF MODEL DATA TO HASH OUT THE FINER DETAILS. ATTM...ECMWF IS
FURTHER NORTH...RESULTING IN THE WETTER SOLN WHILE THE GFS PASSES
THE MAIN LOW SOUTH FRI NIGHT. SFC HIGH PRESSURE TRIES TO BUILD
BACK IN FOR THE END OF THE WEEKEND.
TAX
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
ANOTHER WAVE PASSING ALONG THE COLD FRONT IS GENERATING SOME
MVFR/IFR SHOWERS THROUGH MUCH OF THE AREA...BUT SHOULD PASS TO THE
EAST BY 20Z-22Z. DRYING IN THE MID-LEVELS SHOULD RESULT IN A SPELL
OF VFR THIS EVENING AND TONIGHT WITH HIGH CLOUDS LINGERING. THE
NEXT WAVE PUSHES SOUTH TO NORTH TUES MORNING SPREADING MVFR/IFR
CIGS ALONG WITH RAIN AND IN SOME OF THE ERN AND NRN TERMINALS A
WINTRY MIX. COLD TEMPERATURES INVADING THE AREA CURRENTLY WILL
SET-UP FZRA POTENTIAL FOR MGW-LBE-DUJ. ATTM...HANDLED FZRA WITH
PROB30 GROUPS...AS SOME UNCERTAINTY STILL EXISTS. PRECIPITATION
SHOULD BE CONFINED TO THE ERN 2/3 OF THE CWA...BUT MVFR/IFR CIGS
SHOULD BE PREVALENT THROUGH TUES.
OUTLOOK.../TUESDAY THROUGH FRIDAY/...
MVFR RESTRICTIONS ARE LIKELY TO CONTINUE BEFORE A COLD FRONT
PASSES WEDS NIGHT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST
TUESDAY FOR MDZ001.
OH...NONE.
PA...FREEZING RAIN ADVISORY FROM 7 AM TUESDAY TO 7 AM EST WEDNESDAY
FOR PAZ009-015-016-023.
FREEZING RAIN ADVISORY FROM 7 AM TO 9 PM EST TUESDAY FOR
PAZ074-076.
WV...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST
TUESDAY FOR WVZ023-041.
&&
$$
SYNOPSIS...98
NEAR TERM...98
SHORT TERM...98
LONG TERM...TAX
AVIATION...TAX
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
101 PM EST MON DEC 1 2014
.SYNOPSIS...
AN ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THE FIRST PART OF
THE WORK WEEK BEFORE HIGH PRESSURE SERVES UP A QUIET THURSDAY. YET
ANOTHER WEATHER SYSTEM TAKES AIM AT OUR REGION FRIDAY INTO
SATURDAY WITH THE POTENTIAL FOR A WINTRY MIX.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BAROCLINIC ZONE IS THROUGH MOST OF THE CWA AS OF 16Z...HOWEVER MID
LEVEL POCKET OF INSTABILITY IS TRAVERSING ALONG THE COOL SIDE OF
THE BOUNDARY. BROUGHT LKLY AND CAT POPS TO THE I-76 CORRIDOR
THROUGH THE EARLY AFTERNOON AS BATCH OF RAIN MOVES THROUGH. STILL
CARRY HIGH POPS SOUTH OF THE MASON DIXON LINE INTO THE EVENING
HOURS. IT WILL BE RACE IF THE COLD AIR JUST ABOVE THE SURFACE CAN
CATCH UP CREATING A PERIOD OF SNOW AND SLEET AT THE VERY END. FOR
NOW...OPTED TO KEEP A WINTRY MIX THIS IN PLACE ACROSS EASTERN OHIO
BASED LATEST HRRR SIMULATED REFLECTIVITY AND PTYPE ALGORITHM.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
LATEST 12Z OPERATIONAL NCEP RUNS CONTINUE THEME OF PREVIOUS DAY SOLUTIONS
ALONG WITH OFFSETTED HOURS OF SREF AND THEIR RESPECTIVE
ENSEMBLES OF A WINTRY MIX TUESDAY INTO WEDNESDAY MORNING. QPF VALUES
HAVE TRENDED NORTHWARD...HOWEVER LOOKING AT CROSS SECTIONS OF
UVV...MOISTURE...AND STABILITY HARD TO SEE THAT MUCH QPF OVER
GARRETT AND TUCKER. RECENT EVENTS AND THEIR HIGH BIAS ALSO
SUPPORTS LOWER LIQUID AMOUNTS THAN PROJECTED.
AS COLD AIR INFILTRATES THE REGION TONIGHT AND TRANSITORY SURFACE
ANTICYCLONE MOVES TO NEW ENGLAND...WARM LAYER ALOFT DEVELOPS IN
A COLD AIR DAMMING SETUP. AS ELUDED TOO IN MY PREVIOUS
DISCUSSIONS...AGEOSTROPHIC FLOW IS NOT THAT STRONG...HENCE ONLY A 40
KNOT BARRIER JET ALONG THE APPALACHIANS. IN SIGNIFICANT ICING
EVENTS...THIS FLOW WOULD BE NEARLY A FACTOR OF TWO HIGHER.
INHERITED FORECAST COVERS THIS AREA WELL WITH TIMING AND PCPN
CHANGE OVER. ALL LOCATIONS IN THE EASTERN PERIPHERY OF THE CWA
COULD SEE A PERIOD OF SNOW AND/OR SLEET AT THE ONSET BEFORE A
SWITCH OVER TO FZRA. BUFR SOUNDINGS SHOW MAX WARM LAYER ALOFT
TEMPERATURES CLIMBING BETWEEN 1C AND 3C ACROSS EASTERN PA ZONES AND
WITH OVERNIGHT TEMPS FALLING BACK WELL INTO THE 20S...A PERIOD OF
FZRA IS PREDICTED FROM FOREST CO SOUTH INTO EASTERN FAYETTE
COUNTY.
HOISTED A FREEZING RAIN ADVISORY IN COLLABORATION WITH WFO STATE
COLLEGE TUESDAY MORNING THROUGH DAYBREAK WEDNESDAY. ELECTED TO END
ADVISORY FOR EASTERN WESTMORELAND AND FAYETTE COUNTIES TUESDAY
NIGHT GIVEN BL FLOW SHOULD ERADICATE COLD AIR AT THE SFC EVEN
ACROSS THE DEEPER VALLEYS BETWEEN CHESTNUT AND LAUREL RIDGES.
FARTHER NORTH...CONFIDENCE IS HIGHER FOR COLD AIR TO STAY LOCKED
IN PLACE...WHICH FOLLOWS CLIMOTOLOGICAL NORM. CLARION COUNTY WAS
THROWN IN...HOWEVER THEY SHOULD SWITCH OVER TO RAIN A FEW HOURS
SOONER THAN THEIR COUNTERPARTS TO THE NORTH /FOREST/ AND EAST
/JEFFERSON/.
ONE POSITIVE THING HEADING INTO THIS EVENT IS GIVEN THE RECENT
WARM WEATHER...THE GROUND WILL NOT BE AS COLD AS IT WAS FOR THE
ICING EVENT IN MID NOVEMBER. WE STILL DO NOT EXPECT A SIGNIFICANT
ICE STORM FOR ANY OF OUR COUNTIES. IF THE SOUTHEAST WINDS ARE
STRONG THAN EXPECTED...IT IS POSSIBLE THE GARRETT AND TUCKER COULD
SEE IN EXCESS OF A QUARTER OF AN INCH...BUT AFTER REVIEW OF PLUME
DIAGRAMS FOR 2G4 AND PIE SIDED WITH THE MEAN OF THE PAST FEW RUNS
WHICH PLACES STORM TOTAL ICE ACCUMULATION AROUND 0.15 TO 0.20
INCHES. A QUARTER OF AN INCH OF ICE IS NEEDED FOR AN ICE STORM
WARNING.
TEMPERATURES WERE A BLEND OF THE ONGOING FORECAST AND THE ADJMET
BIAS CORRECTED GRIDS. A GRADUAL WARM UP TO SEASONAL NUMBER IN THE
LOWER TO MID 40S IS SLATED FOR MID WEEK.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
SYSTEM DEVELOPING ACROSS THE CENTRAL PLAINS WILL PUSH NORTHEAST
INTO THE REGION THURSDAY NIGHT INTO FRIDAY. HAVE KEPT POPS IN THE
FORECAST LONGER WITH THE FRONT...AS PRECIPITATION MAY NOW LINGER
INTO SATURDAY AND POSSIBLY EVEN SATURDAY NIGHT IF THE 00Z ECMWF
SOLUTION IS CORRECT. COULD POSSIBLY SEE MIXED PRECIPITATION EACH
NIGHT DEPENDING ON TEMPERATURES. RIDGE OF HIGH PRESSURE BUILDS IN
BY SUNDAY...ALLOWING FOR A RETURN TO DRY WEATHER. TEMPERATURES
WILL BE SEASONABLE THROUGH THE PERIOD.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
ANOTHER WAVE PASSING ALONG THE COLD FRONT IS GENERATING SOME
MVFR/IFR SHOWERS THROUGH MUCH OF THE AREA...BUT SHOULD PASS TO THE
EAST BY 20Z-22Z. DRYING IN THE MID-LEVELS SHOULD RESULT IN A SPELL
OF VFR THIS EVENING AND TONIGHT WITH HIGH CLOUDS LINGERING. THE
NEXT WAVE PUSHES SOUTH TO NORTH TUES MORNING SPREADING MVFR/IFR
CIGS ALONG WITH RAIN AND IN SOME OF THE ERN AND NRN TERMINALS A
WINTRY MIX. COLD TEMPERATURES INVADING THE AREA CURRENTLY WILL
SET-UP FZRA POTENTIAL FOR MGW-LBE-DUJ. ATTM...HANDLED FZRA WITH
PROB30 GROUPS...AS SOME UNCERTAINTY STILL EXISTS. PRECIPITATION
SHOULD BE CONFINED TO THE ERN 2/3 OF THE CWA...BUT MVFR/IFR CIGS
SHOULD BE PREVALENT THROUGH TUES.
OUTLOOK.../TUESDAY THROUGH FRIDAY/...
MVFR RESTRICTIONS ARE LIKELY TO CONTINUE BEFORE A COLD FRONT
PASSES WEDS NIGHT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST
TUESDAY FOR MDZ001.
OH...NONE.
PA...FREEZING RAIN ADVISORY FROM 7 AM TUESDAY TO 7 AM EST WEDNESDAY
FOR PAZ009-015-016-023.
FREEZING RAIN ADVISORY FROM 7 AM TO 9 PM EST TUESDAY FOR
PAZ074-076.
WV...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST
TUESDAY FOR WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1146 AM EST MON DEC 1 2014
.SYNOPSIS...
AN ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THE FIRST PART OF
THE WORK WEEK BEFORE HIGH PRESSURE SERVES UP A QUIET THURSDAY. YET
ANOTHER WEATHER SYSTEM TAKES AIM AT OUR REGION FRIDAY INTO
SATURDAY WITH THE POTENTIAL FOR A WINTRY MIX.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BAROCLINIC ZONE IS THROUGH MOST OF THE CWA AS OF 16Z...HOWEVER MID
LEVEL POCKET OF INSTABILITY IS TRAVERSING ALONG THE COOL SIDE OF
THE BOUNDARY. BROUGHT LKLY AND CAT POPS TO THE I-76 CORRIDOR
THROUGH THE EARLY AFTERNOON AS BATCH OF RAIN MOVES THROUGH. STILL
CARRY HIGH POPS SOUTH OF THE MASON DIXON LINE INTO THE EVENING
HOURS. IT WILL BE RACE IF THE COLD AIR JUST ABOVE THE SURFACE CAN
CATCH UP CREATING A PERIOD OF SNOW AND SLEET AT THE VERY END. FOR
NOW...OPTED TO KEEP A WINTRY MIX THIS IN PLACE ACROSS EASTERN OHIO
BASED LATEST HRRR SIMULATED REFLECTIVITY AND PTYPE ALGORITHM.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
LATEST 12Z OPERATIONAL NCEP RUNS CONTINUE THEME OF PREVIOUS DAY SOLUTIONS
ALONG WITH OFFSETTED HOURS OF SREF AND THEIR RESPECTIVE
ENSEMBLES OF A WINTRY MIX TUESDAY INTO WEDNESDAY MORNING. QPF VALUES
HAVE TRENDED NORTHWARD...HOWEVER LOOKING AT CROSS SECTIONS OF
UVV...MOISTURE...AND STABILITY HARD TO SEE THAT MUCH QPF OVER
GARRETT AND TUCKER. RECENT EVENTS AND THEIR HIGH BIAS ALSO
SUPPORTS LOWER LIQUID AMOUNTS THAN PROJECTED.
AS COLD AIR INFILTRATES THE REGION TONIGHT AND TRANSITORY SURFACE
ANTICYCLONE MOVES TO NEW ENGLAND...WARM LAYER ALOFT DEVELOPS IN
A COLD AIR DAMMING SETUP. AS ELUDED TOO IN MY PREVIOUS
DISCUSSIONS...AGEOSTROPHIC FLOW IS NOT THAT STRONG...HENCE ONLY A 40
KNOT BARRIER JET ALONG THE APPALACHIANS. IN SIGNIFICANT ICING
EVENTS...THIS FLOW WOULD BE NEARLY A FACTOR OF TWO HIGHER.
INHERITED FORECAST COVERS THIS AREA WELL WITH TIMING AND PCPN
CHANGE OVER. ALL LOCATIONS IN THE EASTERN PERIPHERY OF THE CWA
COULD SEE A PERIOD OF SNOW AND/OR SLEET AT THE ONSET BEFORE A
SWITCH OVER TO FZRA. BUFR SOUNDINGS SHOW MAX WARM LAYER ALOFT
TEMPERATURES CLIMBING BETWEEN 1C AND 3C ACROSS EASTERN PA ZONES AND
WITH OVERNIGHT TEMPS FALLING BACK WELL INTO THE 20S...A PERIOD OF
FZRA IS PREDICTED FROM FOREST CO SOUTH INTO EASTERN FAYETTE
COUNTY.
HOISTED A FREEZING RAIN ADVISORY IN COLLABORATION WITH WFO STATE
COLLEGE TUESDAY MORNING THROUGH DAYBREAK WEDNESDAY. ELECTED TO END
ADVISORY FOR EASTERN WESTMORELAND AND FAYETTE COUNTIES TUESDAY
NIGHT GIVEN BL FLOW SHOULD ERADICATE COLD AIR AT THE SFC EVEN
ACROSS THE DEEPER VALLEYS BETWEEN CHESTNUT AND LAUREL RIDGES.
FARTHER NORTH...CONFIDENCE IS HIGHER FOR COLD AIR TO STAY LOCKED
IN PLACE...WHICH FOLLOWS CLIMOTOLOGICAL NORM. CLARION COUNTY WAS
THROWN IN...HOWEVER THEY SHOULD SWITCH OVER TO RAIN A FEW HOURS
SOONER THAN THEIR COUNTERPARTS TO THE NORTH /FOREST/ AND EAST
/JEFFERSON/.
ONE POSITIVE THING HEADING INTO THIS EVENT IS GIVEN THE RECENT
WARM WEATHER...THE GROUND WILL NOT BE AS COLD AS IT WAS FOR THE
ICING EVENT IN MID NOVEMBER. WE STILL DO NOT EXPECT A SIGNIFICANT
ICE STORM FOR ANY OF OUR COUNTIES. IF THE SOUTHEAST WINDS ARE
STRONG THAN EXPECTED...IT IS POSSIBLE THE GARRETT AND TUCKER COULD
SEE IN EXCESS OF A QUARTER OF AN INCH...BUT AFTER REVIEW OF PLUME
DIAGRAMS FOR 2G4 AND PIE SIDED WITH THE MEAN OF THE PAST FEW RUNS
WHICH PLACES STORM TOTAL ICE ACCUMULATION AROUND 0.15 TO 0.20
INCHES. A QUARTER OF AN INCH OF ICE IS NEEDED FOR AN ICE STORM
WARNING.
TEMPERATURES WERE A BLEND OF THE ONGOING FORECAST AND THE ADJMET
BIAS CORRECTED GRIDS. A GRADUAL WARM UP TO SEASONAL NUMBER IN THE
LOWER TO MID 40S IS SLATED FOR MID WEEK.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
SYSTEM DEVELOPING ACROSS THE CENTRAL PLAINS WILL PUSH NORTHEAST
INTO THE REGION THURSDAY NIGHT INTO FRIDAY. HAVE KEPT POPS IN THE
FORECAST LONGER WITH THE FRONT...AS PRECIPITATION MAY NOW LINGER
INTO SATURDAY AND POSSIBLY EVEN SATURDAY NIGHT IF THE 00Z ECMWF
SOLUTION IS CORRECT. COULD POSSIBLY SEE MIXED PRECIPITATION EACH
NIGHT DEPENDING ON TEMPERATURES. RIDGE OF HIGH PRESSURE BUILDS IN
BY SUNDAY...ALLOWING FOR A RETURN TO DRY WEATHER. TEMPERATURES
WILL BE SEASONABLE THROUGH THE PERIOD.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
COLD FRONT WILL COMPLETE ITS PASSAGE OF THE FORECAST AREA BY LATE
MORNING...VEERING THE WINDS AT ALL SITES TO NORTHWEST. MGW IS ONLY
SITE THAT HAS NOT DROPPED TO IFR CONDITIONS...WITH LIMITED
CONFIDENCE THAT IFR CIGS WILL OCCUR. HAVE TRENDED SLIGHTLY SLOWER
WITH RECOVERY TO VFR FROM 06Z TAF ISSUANCE...BUT ALL SITES SHOULD
REACH VFR BY LATE AFTERNOON.
OUTLOOK.../TUESDAY THROUGH FRIDAY/...
MVFR RESTRICTIONS ARE LIKELY WITH AS A COLD FRONT PASSES MID
WEEK.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST
TUESDAY FOR MDZ001.
OH...NONE.
PA...FREEZING RAIN ADVISORY FROM 7 AM TUESDAY TO 7 AM EST WEDNESDAY
FOR PAZ009-015-016-023.
FREEZING RAIN ADVISORY FROM 7 AM TO 9 PM EST TUESDAY FOR
PAZ074-076.
WV...FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 11 PM EST
TUESDAY FOR WVZ023-041.
&&
$$
SYNOPSIS...98
NEAR TERM...98
SHORT TERM...98
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
831 PM EST TUE DEC 2 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 312 PM EST TUE DEC 2 2014
LOW PRESSURE TRACKING NORTH OF THE GREAT LAKES WILL BRING SOME
LIGHT SNOW TONIGHT WITH LITTLE OR NO ACCUMULATION. GENERALLY FAIR
WEATHER WILL FOLLOW FOR THIS WEEK.
&&
.UPDATE...
ISSUED AT 831 PM EST TUE DEC 2 2014
WE HAVE UPDATED THE FCST THIS EVENING TO BUMP UP THE SNOW CHCS...
ESPECIALLY UP ACROSS THE NW PORTION OF THE CWFA. RADAR SHOWS THE
LIGHT SNOW IS ON SCHEDULE AS MID AND UPPER LEVEL MOISTURE UP NORTH
AHEAD OF THE SHORT WAVE IS STARTING TO OVERLAP WITH LOW LEVEL
MOISTURE ADVECTING IN FROM THE SOUTH. THE BEST OVERLAP OCCURS
ACROSS THE NW PORTION OF THE CWFA...ALONG WITH SOME ADDED MOISTURE
OCCURRING UP THERE DUE TO A CONTRIBUTION FROM THE LAKE. DELTA T/S
ARE RELATIVELY SMALL...SO NOT MUCH TEXTBOOK LAKE ENHANCEMENT GOING ON.
THE MID AND UPPER LEVEL MOISTURE WILL MOVE OUT OF THE AREA QUICKLY
DURING THE LATE EVENING AND EARLY OVERNIGHT HOURS.
WE ARE STILL EXPECTING A CHC OF SOME PATCHY FREEZING DRIZZLE DOWN
SOUTH...FURTHER REMOVED FROM THE DEEPER MOISTURE ALLOWING FOR AN
UNSATURATED DGZ. THIS IS NOT EXPECTED TO BE SIGNIFICANT OR LONG
DURATION IN NATURE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 312 PM EST TUE DEC 2 2014
PRETTY QUIET WEATHER TONIGHT THROUGH THURSDAY NIGHT WITH THE ONLY
CHANCE FOR ANY MEASURABLE PRECIP BEING TONIGHT...WHICH SHOULD NOT
AMOUNT TO MUCH. RADAR CURRENTLY SHOWING AREA OF LIGHT SNOW ACROSS
WESTERN WISCONSIN IN AN AREA OF ISENTROPIC ASCENT AND THIS WILL
MOVE EAST TONIGHT WITH LIGHT SNOW PROGGED TO ARRIVE AROUND 01Z
ACROSS THE WESTERN ZONES PER THE HRRR. EXPECT ANY ACCUMS TO BE AN
INCH OR LESS WITH THE BEST CHANCE ACROSS THE NORTHERN FORECAST
AREA.
THE DGZ DRIES OUT BETWEEN 06Z AND 12Z AND THERE REMAINS SOME LIFT
IN THE SHALLOW STRATUS DURING AND AFTER THAT TIME...SO SOME PATCHY
FREEZING DRIZZLE IS POSSIBLE...BUT AGAIN THIS SHOULD BE FAIRLY
LIGHT AND IS NOT EXPECTED TO CAUSE ANY MAJOR IMPACTS.
SOME LIGHT LAKE EFFECT SNOW SHOWERS ARE POSSIBLE ACROSS THE
NORTHWEST FORECAST AREA EARLY WEDNESDAY BEFORE SFC HIGH BUILDS IN
AND INVERSION HEIGHTS CRASH. THIS SFC HIGH WILL BRING FAIR WEATHER
THROUGH THE REST OF THE NEAR TERM.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 312 PM EST TUE DEC 2 2014
MEDIUM RANGE MODELS CONTINUE TO SHOW A SOUTHERN STREAM SYSTEM
PULLING ACROSS THE TN VALLEY FRIDAY NIGHT AND SATURDAY. WE SHOULD
REMAIN ON THE NORTHERN EDGE OF THIS STORM. SOME LIGHT RAIN...
POSSIBLY MIXED WITH SNOW...MAY OCCUR NEAR I-94 OTHERWISE IT APPEARS
THE REST OF THE CWA REMAINS DRY.
AFTER A FAIRLY QUIET PERIOD A NORTHERN STREAM SYSTEM TAKES SHAPE
OVER THE NORTHERN PLAINS BY THE END OF THE WEEKEND. THIS SHOULD
BRIEFLY BRING TEMPS ABOVE NORMAL SATURDAY NIGHT THROUGH SUNDAY NIGHT
AS SOUTHERLY WINDS PUSH IN AHEAD OF THE DEVELOPING SYSTEM. THE
STORM AGGRESSIVELY GETS WOUND UP AND SHOULD GIVE US WINDY CONDITIONS
BY MONDAY...AND THEN TRANSFERS ENERGY INTO A NOREASTER INTO MONDAY
NIGHT. HOWEVER THE BEST MOISTURE AND DYNAMICS REMAINS TO OUR NORTH
AND EAST...SO PCPN OVER SW MI LOOKS FAIRLY MINIMAL. COOLER TEMPS
AND SOME LIGHT LAKE EFFECT SNOW LOOKS POSSIBLE BEHIND THE SYSTEM
LATER MONDAY AND CARRYING INTO TUESDAY WITH H8 TEMPS DROPPING TO
AROUND -6C.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 648 PM EST TUE DEC 2 2014
MVFR CIGS WILL BECOME IFR IN SNOW BETWEEN 03Z AND 09Z...ONLY TO
RETURN TO VFR BY 18Z. SOME FREEZING DRIZZLE IS POSSIBLE BTW 09Z
AND 15Z (NOT IN TAFS CURRENTLY BUT IS POSSIBLE).
CURRENTLY MVFR CIGS HAVE OVERSPREAD MOST OF OUR TAF SITES (EXCEPT
GRR) WITH ABOUT HALF THE SITES IN THE FUEL ALT CATEGORY. BY 01Z I
WOULD THINK JUST ABOUT ALL TAF SITES WOULD BE MVFR (FUEL ALT)
CATEGORY AS THE MOISTURE CONTINUES TO STREAM NORTHWARD AHEAD OF
THE COLD FRONT...WHICH IS CURRENTLY NEAR THE MISSOURI RIVER.
THANKS TO GOOD JET FORCING AS THE FRONT COMES THROUGH AND WITH THE
HELP OF LAKE MICHIGAN...I EXPECT A BAND OF SNOW SHOWERS TO MOVE
WEST TO EAST ACROSS THE TAF SITES BETWEEN 03Z AT MKG TO 06Z AT
JXN. THE HRRR AND RAP MODEL LIKE THIS THE MOST AND ARE CURRENTLY
DOING BEST WITH WHERE THE SNOW SHOWERS CURRENTLY ARE(NE TO SW WI).
THIS WILL BRING IFR TO LIFR CONDITIONS TO MKG AND MAYBE GRR. THE
OTHER SITES SHOULD SEE IFR FOR A FEW HOURS.
ONCE THE COLD FRONT COMES THROUGH BTW 06Z AT MKG AND MORE LIKE
10Z AT JXN...WINDS WILL BECOME GUSTY. THIS MAY EVEN RESULT IN SOME
BLOWING SNOW (NOT IN TAFS CURRENTLY). A BIGGER ISSUE THROUGH IS
THAT THE MOISTURE DEPTH MAY NOT BE DEEP ENOUGH FOR SNOW FLAKES TO
FORM AFT 09Z OR SO. THAT MAY RESULT IN A PERIOD OF FREEZING
DRIZZLE...THAT ALSO IS NOT IN OUR TAFS BUT MAY BE ADDED LATER.
THE DRY AIR MOVES IN BETWEEN 16Z AND 18Z AND THAT SHOULD BRING VFR
TO ALL TAF SITES.
&&
.MARINE...
ISSUED AT 257 PM EST TUE DEC 2 2014
WINDS AND WAVES WILL CONTINUE HAZARDOUS TO SMALL CRAFT UNTIL
THURSDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 257 PM EST TUE DEC 2 2014
NO HYDRO ISSUES EXPECTED THIS WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST THURSDAY FOR LMZ844>849.
&&
$$
UPDATE...NJJ
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...OSTUNO/JK
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
653 PM EST TUE DEC 2 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE
TROUGH AND ASSOCIATED COLD FRONT MOVING ACROSS THE NORTHERN
MISSISSIPPI VALLEY THIS AFTERNOON. AN AREA OF SNOW WITHIN A
MID-LEVEL FGEN BAND OVER NORTHERN WISCONSIN CONTINUES TO
DEVELOP...AND THE LATEST GUIDANCE PUSHES THIS AREA OF SNOW NORTHEAST
ACROSS THE CENTRAL UPPER PENINSULA LATER THIS AFTERNOON. STRONG
GUSTY WINDS OVER WESTERN LAKE SUPERIOR HAVE BEEN GRADUALLY
DIMINISHING WITH THE APPROACH OF THIS COLD FRONT BUT CONTINUE TO
GUST NEAR GALE FORCE OVER THE EASTERN HALF OF THE LAKE. THE MAIN
FORECAST CONCERNS INCLUDE SNOW ACCUMULATIONS FOLLOWED BY GALE
HEADLINES.
TONIGHT...THE SHORTWAVE TROUGH OVER NORTHERN MINNESOTA WILL
CONTINUE TO MOVE EAST AND ACROSS THE REGION. AHEAD OF THE
SHORTWAVE...QG FORCING/MID-LEVEL FGEN WILL COMBINE WITH MID-LEVEL
LAPSE RATES AROUND 6.5 C/KM TO PRODUCE A BAND OF SNOW ACROSS
CENTRAL AND EASTERN SECTIONS OF THE UPPER PENINSULA THIS EVENING.
MODELS PLACE THIS BAND OF SNOW AT DIFFERENT LOCATIONS...BUT
OBSERVATIONAL TRENDS SUPPORT LEANING TOWARDS THE MESO
MODELS...WHICH WOULD CREATE THIS HIGHEST SNOW AMOUNTS FROM IRON
MOUNTAIN TO WHITEFISH POINT. CANNOT RULE OUT SOME ENHANCEMENT OFF
LAKE MICHIGAN DUE TO THE SOUTHERLY WINDS AROUND MANISTIQUE AS
WELL. WILL SHOW A GENERAL 1 TO 2 INCHES IN THESE AREAS...BUT COULD
SEE LOCALLY HIGHER AMOUNTS IN THE LAKE ENHANCEMENT AREAS IF THE
MARGINAL DELTA T/S ARE SUFFICIENT. BEHIND THE SHORTWAVE...WINDS
WILL VEER TO THE WEST OVERNIGHT AND CREATE LAKE EFFECT SNOW
SHOWERS FROM ONTONAGON TO THE TIP OF THE KEWEENAW. SUBSIDENCE
BEHIND THE SHORTWAVE WILL LIMIT ACCUMS TO SUB ADVISORY LEVELS.
LOWS RANGING FROM THE MIDDLE SINGLE DIGITS SOUTH-CENTRAL TO THE
MIDDLE TEENS NEAR THE GREAT LAKES.
WEDNESDAY...AS THE SHORTWAVE EXITS THE REGION DURING THE
MORNING...VEERING WINDS TO THE WNW WILL BE COLD AND DRY AIR
ADVECTING OVER THE COURSE OF THE DAY. HIGH TEMPERATURES WILL BE A
FEW DEGREES COLDER AS A RESULT. DELTA T/S WILL BECOME MORE
FAVORABLE FOR LAKE EFFECT SNOW IN THE WESTERLY SNOW BELTS...BUT
THAT WILL BE COUNTERACTED BY THE INCOMING DRY AIRMASS.
REGARDLESS...SNOW INTENSITY SHOULD INCREASE FROM GRAND MARAIS
THROUGH WHITEFISH POINT IN THE AFTERNOON AS WIND DIRECTIONS VEER.
COULD SEE ANOTHER INCH OR TWO IN THE SNOW BELTS. HIGHS RANGING
FROM THE UPPER TEENS SOUTHWEST TO THE MIDDLE 20S EAST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
A RELATIVELY FLAT ZONAL FLOW ACROSS THE CONUS WL KEEP ARCTIC AIR
LOCKED NORTH IN CANADA AND LIMIT SNOW POTENTIAL OVER UPR MI THRU
SAT. A QUICK MOVING SHORTWAVE TROF IS FCST TO REACH THE GREAT
LAKES REGION SUNDAY NGT/MON AND BRING THE NEXT CHC OF SYNOPTIC
SNOW...LAKE EFFECT SNOW SHWRS TO THE AREA. TOO EARLY YET FOR
SPECIFICS AS THE MDLS HAVE DIFFERENCES ON THE SPEED AND DEPTH OF
THE SHORTWAVE TRFO AS WELL AS THE AMOUNT OF WARM AIR THAT MAY GET
DRAWN NORTH AHEAD OF THE SYSTEM WHICH MAY LIMIT ACCUMULATIONS.
TEMPS WL LIKELY END UP CLOSE TO NORMAL WITH BRIEF WARM-UPS
FOLLOWED BY BRIEF COOL DOWNS.
W-NW WINDS TO CONT INTO WED EVENING...BRINGING LAKE EFFECT SNOW
SHWRS TO MUCH OF THE NRN SECTION OF UPR MI. KEWEENAW...HOUGHTON...
ALGER AND LUCE COUNTIES TO BE THE MOST SUSCEPTIBLE TO ACCUMULATING
SNOW...ESPECIALLY THE LATTER 2 COUNTIES WHO HAVE THE LONGEST
FETCH. ADDITIONAL ACCUMULATIONS TO RANGE FROM AN INCH OR LESS NW
SECTIONS OF THE FORECAST AREA...TO 1 TO 3 INCHES FOR ERN SECTIONS.
THE LAKE EFFECT WL TEND TO WEAKEN OVER THE WRN U.P. LATER WED NGT
AS WINDS BEGIN TO BACK TO THE W-SW DUE TO THE PASSAGE OF A SURFACE
RIDGE OF HI PRES. BEFORE THE SURFACE RIDGE ARRIVES...IT COULD BE A
GUSTY EVENING OVER THE REGION WITH WIND GUSTS APPROACHING 30 MPH
ALONG THE LAKE SUPERIOR SHORELINE. THIS WL GENERATE BLOWING/DRIFTING
OF THE NEW SNOW. QUITE A RANGE IN TEMPS EXPECTED WED NGT BETWEEN THE
DECREASING CLODUS/DIMINISHING WINDS OVER WRN SECTIONS AND MORE
CLOUDS/WIND OVER ERN SECTIONS. LOOK FOR READINGS TO RANGE FROM A
COUPLE OF DEGS EITHER SIDE OF ZERO INTERIOR WEST TO THE MID-TEENS
FROM GRAND MARAIS EWD.
AS THE HIGH PRESSURE SLIDES TO THE EAST ON THU...RETURN FLOW
DEVELOPS ACROSS UPR MI AS WINDS BACK TO THE S-SW. PRETTY STRONG
SURGE OF WAA INDICATED BY THE MODELS AS 8H TEMPS CLIMB FROM THE
TEENS BELOW ZERO TO THE SINGLE DIGITS BELOW ZERO(C). THE
ISENTROPIC LIFT IS NOT STRONG ENUF TO ALLOW PCPN TO DEVELOP...
HOWEVER THERE IS ENUF LIFT TO BRING MORE CLOUDS BACK INTO THE
PICTURE...ESPECIALLY DURING THE AFTERNOON. THE COMBINATION OF A
COLD START TO THE DAY AND INCREASING CLOUDS WL COUNTER THE WARMING
TEMPS ALOFT...THUS MAX TEMPS TO ONLY REACH THE LOWER TO MID 20S.
QUIET CONDITIONS EXPECTED THU NGT AS THE S-SW WINDS TO PERSIST AND
LITTLE EVIDENCE OF ANY LIFTING MECHANISM ADVERTISED BY THE MODELS.
STILL A DECENT AMOUNT OF CLOUDS ANTICIPATED AND THIS WL HELP HOLD
TEMPS UP A BIT. LOOK FOR MIN TEMPS TO SETTLE MAINLY INTO THE TEENS.
A WEAK COLD FRONT IS FCST TO MOVE INTO THE REGION FRI AFTERNOON AND
VEER THE WINDS MORE TO THE W-NW BY 00Z SAT. LITTLE IN THE WAY OF
MOISTURE IS APPARENT AS A SRN STREAM SYSTEM OVER THE OZARKS/TN
VALLEY INTERCEPTS ANY GULF MOISTURE. PREFER TO LEAVE THE FCST DRY
PER PREVIOUS SHIFT. MAX TEMPS TO MAINLY BE IN THE 30-35 DEG RANGE
WITH THE WARMER READINGS IN THE EAST.
A LARGE CANADIAN HI PRES TO BE OUR MAIN WEATHER FEATURE FOR THE
FIRST HALF OF THE UPCOMING WEEKEND AND PROVIDE A MOSTLY DRY
STRETCH OF WEATHER. THE ONLY EXCEPTION WOULD BE A MINIMAL CHC OF
LAKE EFFECT SNOW SHWRS NEAR LAKE SUPERIOR DUE TO N-NW WINDS. 8H
TEMPS ONLY AROUND -8C OVER THE LAKE WOULD LIMIT SNOW POTENTIAL.
TRAJS BECOME UNFAVORABLE BY SAT...SO DRY CONDITIONS TO PREVAIL.
MAX TEMPS ON SAT TO AGAIN BE GENERALLY IN THE 30-35 DEG RANGE WITH
A FEW UPR 20S OVER THE INTERIOR WEST.
AFTER A QUIET SAT NGT...ATTENTION TURNS TO THE WEST WHERE A WEAK
SFC LOW/CDFNT AND SHORTWAVE TROF ARE PROGGED TO MOVE EAST INTO THE
UPR MS VALLEY/WRN GREAT LAKES ON SUNDAY. 12Z GFS/GEM ARE SLOWER
WITH THE MOVEMENT OF THIS SYSTEM AND BARELY GET THE LEADING EDGE
OF PCPN TO FAR WRN SECTIONS BY 00Z MON. MEANWHILE...THE ECMWF/UKMET
ARE FASTER OVERALL AND WOULD BRING THE PCPN CHCS THRU ALMOST ALL
OF UPR MI BY 00Z MON. DUE TO THE WIDE DISCREPANCY IN TIMING...HAVE
FOLLOWED THE CONSENSUS SOLUTION FOR NOW WHICH BRINGS PCPN CHCS THRU
MOST OF UPR MI SUNDAY AFTERNOON. ANOTHER POTENTIAL CONCERN IS PCPN
TYPE...ESPECIALLY IF THE GFS/GEM ARE CORRECT WHERE A MIX WOULD BE
POSSIBLE HEADED INTO SUNDAY EVENING.
THE CHCS FOR BOTH SYNOPTIC AND LAKE EFFECT SNOWS WL CONT INTO
SUNDAY NGT AS THE SYSTEM PUSHES ACROSS THE GREAT LAKES. MUCH TOO
EARLY FOR ANY ACCUMULATION NUMBERS...ESPECIALLY DUE TO THE
DIFFERENCES IN THE MODELS. LAKE EFFECT SNOW SHWRS BECOME MORE OF
AN ISSUE HEADED INTO MON AS WINDS EVENTUALLY BECOME NW AND CAA
SWEEPS SWD SENDING 8H TEMPS DOWN INTO THE -10 TO -15 DEG RANGE(C).
HAVE PLACED HIGHER CHC POPS OVER THE TYPICALLY FAVORED LOCATIONS
FROM KEWEENAW EWD. THE LAKE EFFECT POTENTIAL IS EXPECTED TO LINGER
INTO MON NGT BEFORE GRADUALLY TAPERING OFF HEADED INTO TUE AS
ANOTHER AREA OF HI PRES BUILDS INTO THE REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 651 PM EST TUE DEC 2 2014
AREA OF -SN AFFECTING KSAW WITH IFR CONDITIONS IS QUICKLY MOVING E.
EXPECT IMPROVEMENT TO MVFR AROUND 01Z AND TO VFR BY 04Z. AT KCMX...
LOW-LEVEL WINDS ARE BECOMING MORE WESTERLY...AND THIS SHOULD RESULT
IN LAKE EFFECT -SHSN/MVFR CONDITIONS BECOMING THE RULE THIS EVENING.
AT KIWD...VFR CONDITIONS WILL LIKELY PREVAIL TONIGHT WITH WINDS
MAINTAINING JUST ENOUGH SOUTHERLY COMPONENT TO KEEP LAKE EFFECT
CLOUDS JUST TO THE N. ON WED...COLDER AIR WILL FLOW INTO THE AREA ON
STRENGTHENING WNW WINDS. AT THE MORE EXPOSED KCMX TERMINAL...WINDS
WILL LIKELY GUST AOA 30KT. COMBINATION OF -SHSN/BLSN WILL LIKELY
LEAD TO PREVAILING LIFR CONDITIONS FROM MID MORNING THRU EARLY AFTN
AT KCMX. AT KIWD...EXPECT CONDITIONS TO FALL TO MVFR AS LAKE EFFECT
-SHSN DRIFT JUST FAR ENOUGH S. AT KSAW...VFR CONDITIONS SHOULD
PREVAIL WED UNDER DOWNSLOPING WNW WINDS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
SOUTHERLY GALES ARE ONGOING ACROSS THE EASTERN HALF OF THE LAKE.
SHOULD SEE WINDS DIMINISH AS A COLD FRONT APPROACHES THE
REGION BY EARLY THIS EVENING. BEHIND THE FRONT...ANOTHER W-NW GALE EVENT
WILL FOLLOW WEDNESDAY AFTERNOON AND NIGHT. BUT SINCE THE WEATHER
PATTERN IS PROGRESSIVE...THE PASSAGE OF THE TRAILING HI PRES RIDGE
THRU THE AREA ON THU WILL RESULT IN DIMINISHING/BACKING WINDS TO
THE SW FOR LATER IN THE WEEK. NO GALES ARE EXPECTED DURING THIS
TIME.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...MPC
LONG TERM...AK
AVIATION...ROLFSON
MARINE...MPC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
649 PM EST TUE DEC 2 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 312 PM EST TUE DEC 2 2014
LOW PRESSURE TRACKING NORTH OF THE GREAT LAKES WILL BRING SOME
LIGHT SNOW TONIGHT WITH LITTLE OR NO ACCUMULATION. GENERALLY FAIR
WEATHER WILL FOLLOW FOR THIS WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 312 PM EST TUE DEC 2 2014
PRETTY QUIET WEATHER TONIGHT THROUGH THURSDAY NIGHT WITH THE ONLY
CHANCE FOR ANY MEASURABLE PRECIP BEING TONIGHT...WHICH SHOULD NOT
AMOUNT TO MUCH. RADAR CURRENTLY SHOWING AREA OF LIGHT SNOW ACROSS
WESTERN WISCONSIN IN AN AREA OF ISENTROPIC ASCENT AND THIS WILL
MOVE EAST TONIGHT WITH LIGHT SNOW PROGGED TO ARRIVE AROUND 01Z
ACROSS THE WESTERN ZONES PER THE HRRR. EXPECT ANY ACCUMS TO BE AN
INCH OR LESS WITH THE BEST CHANCE ACROSS THE NORTHERN FORECAST
AREA.
THE DGZ DRIES OUT BETWEEN 06Z AND 12Z AND THERE REMAINS SOME LIFT
IN THE SHALLOW STRATUS DURING AND AFTER THAT TIME...SO SOME PATCHY
FREEZING DRIZZLE IS POSSIBLE...BUT AGAIN THIS SHOULD BE FAIRLY
LIGHT AND IS NOT EXPECTED TO CAUSE ANY MAJOR IMPACTS.
SOME LIGHT LAKE EFFECT SNOW SHOWERS ARE POSSIBLE ACROSS THE
NORTHWEST FORECAST AREA EARLY WEDNESDAY BEFORE SFC HIGH BUILDS IN
AND INVERSION HEIGHTS CRASH. THIS SFC HIGH WILL BRING FAIR WEATHER
THROUGH THE REST OF THE NEAR TERM.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 312 PM EST TUE DEC 2 2014
MEDIUM RANGE MODELS CONTINUE TO SHOW A SOUTHERN STREAM SYSTEM
PULLING ACROSS THE TN VALLEY FRIDAY NIGHT AND SATURDAY. WE SHOULD
REMAIN ON THE NORTHERN EDGE OF THIS STORM. SOME LIGHT RAIN...
POSSIBLY MIXED WITH SNOW...MAY OCCUR NEAR I-94 OTHERWISE IT APPEARS
THE REST OF THE CWA REMAINS DRY.
AFTER A FAIRLY QUIET PERIOD A NORTHERN STREAM SYSTEM TAKES SHAPE
OVER THE NORTHERN PLAINS BY THE END OF THE WEEKEND. THIS SHOULD
BRIEFLY BRING TEMPS ABOVE NORMAL SATURDAY NIGHT THROUGH SUNDAY NIGHT
AS SOUTHERLY WINDS PUSH IN AHEAD OF THE DEVELOPING SYSTEM. THE
STORM AGGRESSIVELY GETS WOUND UP AND SHOULD GIVE US WINDY CONDITIONS
BY MONDAY...AND THEN TRANSFERS ENERGY INTO A NOREASTER INTO MONDAY
NIGHT. HOWEVER THE BEST MOISTURE AND DYNAMICS REMAINS TO OUR NORTH
AND EAST...SO PCPN OVER SW MI LOOKS FAIRLY MINIMAL. COOLER TEMPS
AND SOME LIGHT LAKE EFFECT SNOW LOOKS POSSIBLE BEHIND THE SYSTEM
LATER MONDAY AND CARRYING INTO TUESDAY WITH H8 TEMPS DROPPING TO
AROUND -6C.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 648 PM EST TUE DEC 2 2014
MVFR CIGS WILL BECOME IFR IN SNOW BETWWEEN 03Z AND 09Z...ONLY TO
RETURN TO VFR BY 18Z. SOME FREEZING DRIZZLE IS POSSIBLE BTW 09Z
AND 15Z (NOT IN TAFS CURRENTLY BUT IS POSSIBLE).
CURRENTLY MVFR CIGS HAVE OVERSPREAD MOST OF OUR TAF SITES (EXCEPT
GRR) WITH ABOUT HALF THE SITES IN THE FUEL ALT CATEGORY. BY 01Z I
WOULD THINK JUST ABOUT ALL TAF SITES WOULD BE MVFR (FUEL ALT)
CATEGORY AS THE MOISTURE CONTINUES TO STREAM NORTHWARD AHEAD OF
THE COLD FRONT...WHICH IS CURRENTLY NEAR THE MISSOURI RIVER.
THANKS TO GOOD JET FORCING AS THE FRONT COMES THROUGH AND WITH THE
HELP OF LAKE MICHIGAN...I EXPECT A BAND OF SNOW SHOWERS TO MOVE
WEST TO EAST ACROSS THE TAF SITES BETWEEN 03Z AT MKG TO 06Z AT
JXN. THE HRRR AND RAP MODEL LIKE THIS THE MOST AND ARE CURRENTLY
DOING BEST WITH WHERE THE SNOW SHOWERS CURRENTLY ARE(NE TO SW WI).
THIS WILL BRING IFR TO LIFR CONDITIONS TO MKG AND MAYBE GRR. THE
OTHER SITES SHOULD SEE IFR FOR A FEW HOURS.
ONCE THE COLD FRONT COMES THROUGH BTW 06Z AT MKG AND MORE LIKE
10Z AT JXN...WINDS WILL BECOME GUSTY. THIS MAY EVEN RESULT IN SOME
BLOWING SNOW (NOT IN TAFS CURRENTLY). A BIGGER ISSUE THROUGH IS
THAT THE MOISTURE DEPTH MAY NOT BE DEEP ENOUGH FOR SNOW FLAKES TO
FORM AFT 09Z OR SO. THAT MAY RESULT IN A PERIOD OF FREEZING
DRIZZLE...THAT ALSO IS NOT IN OUR TAFS BUT MAY BE ADDED LATER.
THE DRY AIR MOVES IN BETWEEN 16Z AND 18Z AND THAT SHOULD BRING VFR
TO ALL TAF SITES.
&&
.MARINE...
ISSUED AT 257 PM EST TUE DEC 2 2014
WINDS AND WAVES WILL CONTINUE HAZARDOUS TO SMALL CRAFT UNTIL
THURSDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 257 PM EST TUE DEC 2 2014
NO HYDRO ISSUES EXPECTED THIS WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST THURSDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...OSTUNO/JK
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
342 PM EST MON DEC 1 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 336 PM EST MON DEC 1 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A PROGRESSIVE...
NEARLY W-E FLOW ALONG THE CNDN BORDER. SHRTWV EMBEDDED WITHIN THIS
FLOW IS CURRENTLY MOVING THRU ERN ONTARIO. LLVL NW FLOW/H85 THERMAL
TROF WITH TEMPS AS LO AS -25 TO -28C RESULTED IN NUMEROUS LK EFFECT
SN SHOWERS MAINLY IN THE W-NW WIND SN BELTS. BUT STRONG SUBSIDENCE
RELATED TO DNVA/DEEP LYR QVECTOR DVGC THAT LOWERED THE INVRN BASE TO
H9-925 AS SHOWN ON THE 12Z INL/MPX RAOBS AS WELL AS TENDENCY FOR THE
LLVL FLOW TO BECOME MORE ACYC WITH APRCH OF SFC HI PRES IN SRN MN IS
LIMITING THE INTENSITY OF THE SN SHOWERS. THE SN SHOWERS ARE ALSO
SHIFTING AS THE FLOW BEGINS TO BACK WITH HI PRES MOVING INTO WI. NW
WIND GUSTS REACHED 45-50 MPH ALONG LK SUP DURING THE MRNG...BUT
WEAKENING PRES GRADIENT FOLLOWING PASSAGE OF PRES RISE CENTER THIS
MRNG IS CAUSING WINDS TO SLOWLY DIMINISH. THE HI WAVES WHIPPED UP BY
THESE STRONG WINDS...AS HI AS 15 FT...AND ABOVE NORMAL LK WATER LVLS
WARRANTED ISSUANCE OF A LK SHORE FLOOD ADVY FOR THE MORE EXPOSED
ALGER/LUCE COUNTIES THAT WL EXPIRE AT 2/00Z. LOOKING TO THE W...
SKIES ARE MOCLR IN MN UNDER HI PRES RDG/AXIS OF LOWEST PWAT OF 0.03
INCH /10-15 PCT OF NORMAL/ REPORTED ON THE 12Z MPX/INL RAOBS...BUT
MORE HI CLDS IN ADVANCE OF A SHRTWV MOVING THRU THE PAC NW/SW CANADA
ARE ALREADY PUSHING INTO WRN MN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LES TRENDS LATE
TODAY...LO TEMPS TNGT WITH PASSAGE OF SFC RDG/VERY DRY AIRMASS AND
THEN POTENTIAL FOR SOME WAA PCPN ON TUE IN THE STRENGTHENING S FLOW
BTWN THE DEPARTING HI PRES AND LO PRES TROF ASSOCIATED WITH SHRTWV
NOW MOVING THRU THE ROCKIES.
LATE TODAY/TNGT...AS THE SFC HI PRES CENTER IN SRN MN SHIFTS E THRU
WI...NRN LOWER MI AND INTO QUEBEC BY 12Z TUE...THE WINDS WL BACK
STEADILY TO THE S...CAUSING LINGERING SN SHOWERS IN THE W-NW WIND SN
BELTS TO SHIFT OUT INTO THE LK BY MIDNGT OR SO. WINDS WL ALSO
DIMINISH THIS EVNG WITH THE ARRIVAL OF THE WEAKER GRADIENT
ASSOCIATED WITH THE HI. CONSIDERING THE VERY DRY INCOMING AIRMASS...
EXPECT TEMPS OVER MUCH OF THE CWA TO DIP AOB ZERO THIS EVNG. BUT
INCOMING HI CLDS RELATED TO STRENGTHENING S FLOW/ISENTROPIC ASCENT
UNDER SHARPENING PRES GRADIENT BTWN DEPARTING SFC HI TO THE E AND LO
PRES TROF IN THE PLAINS WL TEND TO LIMIT THE DIURNAL TEMP FALL AND
CAUSE TEMPS TO RISE OVERNGT. DESPITE THESE LIMITATIONS...TENDED TO
LOWER GOING FCST MIN TEMPS TOWARD -10F OVER THE INTERIOR W AND
SCENTRAL. ANOTHER CONCERN IS POTENTIAL FOR SOME SN SHOWERS TO DVLP
OVERNGT DOWNWIND OF LK MI IN THE S FLOW AND IN PRESENCE OF H85 TEMPS
AS LO AS -8 TO -10C /VS LK WATER TEMP ARND 5C AS REPORTED ON THE NRN
LK MI BUOY/. THE MAIN LIMITING FACTOR ON THE COVERAGE/INTENSITY OF
THESE SN SHOWERS WL BE LO INVRN BASE FCST NEAR 3K FT AGL AND VERY
DRY NATURE OF THE LLVL AIR. THESE SN SHOWERS WL IMPACT MAINLY DELTA
COUNTY AFTER 06Z.
TUE...AREA OF DEEP LYR QVECTOR CNVGC ASSOCIATED WITH DPVA IN ADVANCE
OF APRCHG SHRTWV/PERSISTENT ISENTROPIC ASCENT IN THE SW FLOW BTWN
ACCOMPANYING SFC TROF AND DEPARTING HI PRES IN SE CANADA ARE FCST TO
IMPACT THE CWA. THE MAIN LIMITING FACTOR TO WIDESPREAD PCPN WL BE
MARGINAL MSTR RETURN ARND THE H85 LEVEL. SINCE THE MODELS SHOW SOME
HIER H85 DEWPTS ADVECTING INTO THE E HALF IN THE AFTN UNDER THE DEEP
LYR FORCING AND WHERE THERE WL REMAIN A LK EFFECT COMPONENT IN THE
SW FLOW OFF LK MI WITH H85 TEMPS NEAR -8C...FCST THE HIER POPS/PCPN
TOTALS IN THAT AREA. NOT OUT OF THE QUESTION THERE COULD BE A FEW
INCHES OF SN IN THE ERN CWA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 PM EST MON DEC 1 2014
A VERY PROGRESSIVE PATTERN IS EXPECTED FOR THE LONG TERM
FORECAST...AS THE NORTHERN STREAM JET SLIDES NORTH INTO SOUTHERN
CANADA AND SWEEPS A SERIES OF COLD FRONTS OR TROUGHS EAST ACROSS THE
AREA. BETWEEN THE FRONTS/TROUGHS...AREAS OF HIGH PRESSURE WILL MOVE
THROUGH THE REGION WHICH WILL PROVIDE PERIODS OF PARTLY CLOUDY TO
CLEAR SKIES OVER THE AREA. WITH THE NORTHERN STREAM OF THE JET
SLIDING FARTHER TO THE NORTH...SHOULD SEE A GRADUAL MODERATION TO
THE TEMPERATURES THIS WEEK...POTENTIALLY EVEN BEING A FEW DEGREES
ABOVE NORMAL ON SATURDAY/SUNDAY (NORMAL HIGHS IN THE UPPER 20S TO
LOWER 30S).
THE FIRST TROUGH WILL SWEEP ACROSS THE UPPER GREAT LAKES REGION ON
TUESDAY EVENING...SHIFTING THE GUSTY SOUTHERLY WINDS TO THE WEST BY
WEDNESDAY MORNING. AHEAD OF THE TROUGH...EXPECT THERE TO BE SOME
LINGERING LAKE EFFECT OFF LAKE MICHIGAN OVER DELTA/SCHOOLCRAFT
INTIALLY IN THE EVENING...BUT QUICKLY DEPARTING WITHIN A COUPLE
HOURS. AS THAT DEPARTS...THE INITIAL SURGE OF ENERGY AND DEEPER
MOISTURE FROM THE SHORTWAVE WILL MOVE THROUGH THE EASTERN CWA AND
PRODUCE AN INCREASE IN COVERAGE/INTENSITY OF THE SNOW SHOWERS. SOME
LOCATIONS MIGHT PICK UP A QUICK INCH OR TWO OF SNOW BEFORE IT
DEPARTS SHORTLY AFTER MIDNIGHT. BEHIND THE TROUGH...BOUNDARY LAYER
WINDS WILL SHIFT TO THE WEST OR WEST-NORTHEST AND PRODUCE SOME LIGHT
LAKE EFFECT SNOW SHOWERS. ALTHOUGH 875MB TEMPS FALL TO AROUND
-15C...THE STRENGTH OF THE INVERSION AT THAT LEVEL WILL LIKELY KEEP
THE CLOUD DEPTH LIMITED AND IN TURN THE SNOWFALL AMOUNTS LIGHT. THAT
WILL CONTINUE THROUGH WEDNESDAY MORNING UNTIL A SECONDARY TROUGH
MOVES THROUGH ON WEDNESDAY AFTERNOON (ASSOCIATED WITH ANOTHER
SHORTWAVE ON THE WEST SIDE OF THE DEPARTING UPPER TROUGH). THAT
SHORTWAVE WILL USHER IN COLDER 850MB TEMPS (TO -16C)...WHILE
PROVIDING DEEPER MOISTURE AND RAISING INVERSION HEIGHTS TO 7-8KFT.
THAT WILL LEAD TO A 6-12HR PERIOD OF LIGHT TO MODERATE LAKE EFFECT
SNOW IN THE WEST-NORTHWEST WIND LOCATIONS. WHILE MUCH OF THE CLOUD
IS WITHIN THE DGZ...THINKING THE STRENGTH OF THE WINDS (GUSTING TO
30-40MPH) WILL HELP FRACTURE THE DENDRITES AND LEAD TO SNOW RATIOS
LOWER THAN NORMALLY EXPECTED IN THAT SITUATION.
THAT PERIOD OF LAKE EFFECT WILL QUICKLY DIMINISH FROM WEST TO EAST
WEDNESDAY NIGHT...AS AN AREA OF HIGH PRESSURE SHIFTS EAST INTO THE
AREA. THIS HIGH WILL CONTINUE TO THE EAST ACROSS THE UPPER GREAT
LAKES REGION ON THURSDAY MORNING AND BRING AN END TO MOST OF THE
LAKE EFFECT (OR AT LEAST PUSH IT OVER EASTERN LAKE SUPERIOR AS
WINDS BACK). WINDS WILL BACK TO THE SOUTH BEHIND THE HIGH ON
THURSDAY AFTERNOON AND NIGHT...AHEAD OF THE NEXT TROUGH THAT WILL
MOVE THROUGH THE AREA ON FRIDAY INTO FRIDAY NIGHT. THIS PERIOD
SHOULD BE FAIRLY QUIET AND EXPECT HIGHS TO RISE TOWARDS NORMAL ON
FRIDAY. WITH THE TROUGH BEING FAIRLY WEAK AS IT MOVES
THROUGH...DON/T EXPECT MUCH CHANGE IN THE CONDITIONS BEHIND THE
FRONT AS COLDEST 850MB TEMPS ARE LOCKED UP WELL TO THE NORTH AND
GENERALLY HAVE VALUES AROUND -4C OVER LAKE SUPERIOR. THIS LEADS TO
MARGINAL LAKE EFFECT CLOUD DELTA-T VALUES FRIDAY NIGHT INTO
SATURDAY AS THE NEXT AREA OF HIGH PRESSURE MOVES IN. WITH LIMITED
LOW LEVEL MOISTURE SHOWN ON THE MODELS...WILL JUST GO WITH PARTLY
CLOUDY SKIES OVER THE AREA...ESPECIALLY IN AREAS FAVORED BY
NORTHWEST WIND.
THAT NEXT AREA OF HIGH PRESSURE WILL DEPART ON SATURDAY NIGHT
ALLOWING THE NEXT SHORTWAVE AND SURFACE LOW/TROUGH TO APPROACH THE
AREA FROM THE DAKOTAS SUNDAY INTO SUNDAY NIGHT. WILL FOLLOW A
GENERAL CONSENSUS OF THE GFS/ECMWF AT THIS POINT AND SHOW SLIGHT
CHANCE POPS SPREADING ACROSS THE AREA. THE BIGGEST DIFFERENCE
BETWEEN THE MODELS COMES FROM THE AMOUNT OF COLD AIR THAT MOVES IN
BEHIND THE LOW/TROUGH ON MONDAY (850MB TEMPS OF -4C ON THE GFS AND
-8C ON THE ECMWF). EITHER WAY...THIS APPEARS MARGINAL FOR LAKE
EFFECT AND WILL SHOW DIMINISHING POPS ON MONDAY AS THE SYSTEM
DEPARTS. ALL IN ALL...SATURDAY THROUGH MONDAY THE AREA SHOULD SEE
TEMPERATURES A LITTLE ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1241 PM EST MON DEC 1 2014
EXPECT LINGERING LES AND IFR/LIFR CONDITIONS AT IWD TO GIVE WAY TO
VFR CONDITIONS BY LATE AFTN AS WINDS/BLSN DIMINISH AND THE LLVL
WINDS BACK TOWARD THE SW AND DRIVE THE SHSN N OF THIS SITE. THESE
SAME TRENDS WL OCCUR AT CMX LATER...WITH THE VFR CONDITIONS NOT
ARRIVING UNTIL LATER IN THE EVNG. AT SAW...MVFR CIGS AT TIMES EARLY
IN THE FCST PERIOD WL GIVE WAY TO VFR CONDITIONS AS LARGER SCALE
SUBSIDENCE/DOWNSLOPE WNW FLOW DISSIPATES THE CLDS. FCST LLWS AT ALL
THE SITES OVERNGT ONCE THE FLOW SHIFTS TO THE S AND INCREASES ABOVE
SHALLOW RADIATION INVRN UNDER TIGHTENING PRES GRADIENT BTWN
DEPARTING HI PRES TO THE E AND A LO PRES TROF IN THE PLAINS. THESE
STRONGER WINDS WL TEND TO MIX OUT A BIT ON TUE MRNG AND RESULT IN
SOME GUSTY SFC WINDS. AFTER THE LK EFFECT CLDS DIMINISH THIS AFTN/
EVNG...VFR CONDITIONS WL PREDOMINATE. THE ONLY EXCEPTION MAY BE AT
SAW...WHERE S FLOW OFF LK MI MIGHT DRIVE SOME MVFR SC CIGS FAR ENUF
N TO IMPACT THAT SITE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 336 PM EST MON DEC 1 2014
EXPECT WINDS/FREEZING SPRAY TO DIMINISH AND BACK TOWARD THE W AND SW
WITH PASSAGE OF SFC HI PRES RDG THIS EVNG. ALLOWED GOING HEAVY
FREEZING SPRAY/GALE HEADLINES OVER THE EASTERN LAKE TO END AS
PLANNED. BUT AS THE HI MOVES STEADILY TO THE E AND ANOTHER LO PRES
TROF MOVES INTO THE NORTHERN PLAINS TONIGHT...THE PRES GRADIENT WILL
SHARPEN AND CAUSE S WINDS TO INCREASE. THERE WILL BE A PERIOD OF S
GALES MAINLY OVER THE E HALF OF THE LAKE ON TUE WHEN THE SHARPEST
GRADIENT WILL PASS OVERHEAD. ISSUED A GALE WARNING FOR LAKE SUPERIOR
OPEN WATER ZONES 264>267. THIS GALE EVENT WILL BE RELATIVELY SHORT
LIVED AS THE TROF/WEAKER GRADIENT PASSES W-E THROUGH THE UPPER LAKES
LATE TUE...WITH GALES ENDING TUE EVENING. THERE IS LIKELY TO BE
ANOTHER W-NW GALE EVENT WED AFTERNOON/NIGHT FOLLOWING A COLD FRONTAL
PASSAGE. BUT SINCE THE WEATHER PATTERN IS PROGRESSIVE...THE PASSAGE
OF THE TRAILING HI PRES RIDGE THRU THE AREA ON THU WILL RESULT IN
DIMINISHING/BACKING WINDS TO THE SW FOR LATER IN THE WEEK. NO GALES
ARE EXPECTED DURING THIS TIME.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKESHORE FLOOD ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ006-
007.
LAKE SUPERIOR...
GALE WARNING FROM 10 AM TO 7 PM EST TUESDAY FOR LSZ267.
GALE WARNING FROM 7 AM TO 7 PM EST TUESDAY FOR LSZ266.
GALE WARNING FROM 7 AM TO 1 PM EST TUESDAY FOR LSZ264-265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1206 AM CST Mon Dec 1 2014
.UPDATE:
Issued at 1157 PM CST Sun Nov 30 2014
Precipitation has become more persistent and continues to develop
within an elongated SW-NE oriented moisture convergence zone
stretching from northeast OK along I-44 in MO and I-70 in IL.
While the coverage of precipitation is scattered in general,
persistent waves of scattered precipitation are expected overnight
into early Monday morning. This will occur as cold air/sub-freezing
continues to intensify/spread southward resulting in freezing
rain. We have also had some reports of sleet in the metro area
mixing within the showers. Given the persistence, we could see
some light ice accumulatons/glazing. The greatest impacts will be
on untreated elevated roads - bridges and overpasses. I have issued
a winter weather advisory through 600 am for the aforementioned
corridor into southeast MO and southern IL. The advisory may need
to be expanded past 12z for some areas.
Glass
Issued at 934 PM CST Sun Nov 30 2014
At this point I haven`t seen much in the latest observational and
model data to suggest significant changes are need to the previous
forecast. The cold front has passed through the CWA, stretching
across far southern IL and southeast MO at 03z. Very spotty and
very weak fast moving echoes have begun to show up on regional
radars within the cold air across southern MO and southern IL, but
currently south of the freezing line. These appear to be in
response to isentropic lift over the shallow cold dome. The last
few runs of the RAP and HRRR suggest this may be the pattern the
remainder of the night and into Monday morning with these spotty
small fast-moving blips of precipitation, which will eventually be
occuring in the sub-freezing air as it continues to spread
southward. The current chance pops appear to have this adequately
covered and the only real change was to bump slightly northward
the northern periphery of slight chance pops. The two inch ground
temperature here at the WFO in Weldon Spring is 46 degrees, which
would suggest any ice issues with this spotty ZR would be on
elevated surfaces. Unless something changes, the coverage of
precipitation and associated impacts would be less than needed for
an advisory. We will continue to monitor closely through the
overnight hours should coverage become greater than currently
anticipated and then changes would be required.
Glass
&&
.SHORT TERM: (Through Monday)
Issued at 229 PM CST Sun Nov 30 2014
Main focus remains precip chances thru the period.
Mdls remain in fairly good agreement in most aspects. Still believe
the nrn extent of mdl QPF is overdone due to issues mentioned
yesterday. Mdls prog the weak s/w currently over ern TX/OK region to
move newd this evening. This s/w shud arrive over the srn MO/IL and
KY region about the same time as the 850mb cdfnt. This combination
of low and upper level forcing shud be enuf for precip to develop.
This precip shud develop around 06z tonight and persist thru much of
the night. The main question is exactly where will the precip
develop. Latest mdl guidance continues to suggest this will develop
just SE of the CWA. However, given the uncertainty with location,
will keep high chance PoPs across the far srn tier of counties.
Precip type continues to be a struggle. Precip shud begin as RA and
freeze as the cold air pushes swd thru the region. MO mesonet obs
continue to show 4 inch soil temps in the lower 50 F range across SE
MO. This shud limit ice accumulation to elevated sfcs if any does
occur. That said, these elevated sfcs may also include bridges and
overpasses if untreated. One chance from mdl soundings yesterday is
precip may linger a bit later than prev anticipated. Latest mdl
soundings suggest that if precip continues as far N as KFAM Mon
morning, IP is possible. Have added mention of IP for Mon morning
along the nrn edges of the precip shield, but kept PoPs low for this
time.
Mdls have come into better agreement regarding temps and trended twd
more of a compromise for temps thru the period.
Given the warm sfc temps and uncertainty where precip will develop
late tonight into Mon, will hold off on issuing a headline for now.
However, a headline will likely be needed if precip develops further
N than currently anticipated.
Tilly
.LONG TERM: (Tuesday through Next Sunday)
Issued at 315 PM CST Sun Nov 30 2014
Once the precip moves out of the region on Mon, the sfc ridge will
quickly move thru the region and be S of the CWA by mid day Tues.
With clouds clearing out, ample insolation shud allow temps to climb
into the 40s.
Mdls remain in fairly good agreement thru Thurs. Beyond Thurs, mdl
solns diverge. The ECMWF/GEM are in better agreement regarding mass
fields with a more amplified pattern late this week compared to the
GFS. Have therefore trended twd a ECMWF/GEM compromise. However,
have kept low PoPs lingering across much of the CWA due to the GFS
soln.
One change made from the prev few shifts is a switch from a RA or SN
forecast to a RA or FZRA forecast. Latest GFS soundings do not
support SN thru the extd portion of the forecast. Due to
inconsistencies from one run to the next and differences among mdls
thru the extd periods, have low confidence in any one mdl soln.
However, mdls do come into better agreement for Sun and into next
week as a trof ejects into the Plains. Have trended PoPs slightly
higher late in the period with better mdl agreement.
Tilly
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1141 PM CST Sun Nov 30 2014
Widely scattered showers have developed over southern half of
forecast area and are moving northeast through metro area with
freezing rain and some sleet being reported. Coverage is spotty so
for now kept tafs dry but did add tempo mention of mvfr cigs
through 10z Monday. Rest of taf sites to remain vfr. North winds
to persist with gusts at times over forecast area with vfr
conditions. Winds to become northeasterly by Monday afternoon and
diminish a bit.
Specifics for KSTL:
Widely scattered showers have developed over southern half of
forecast area and are moving northeast through metro area with
freezing rain and some sleet being reported. Coverage is spotty so
for now kept tafs dry but did add tempo mention of mvfr cigs
through 10z Monday. Otherwise, north winds to persist with gusts
at times over forecast area with vfr conditions. Winds to diminish
a bit by late Monday afternoon.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY until 6 AM CST Monday FOR Crawford MO-
Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Madison MO-
Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City
MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO.
IL...WINTER WEATHER ADVISORY until 6 AM CST Monday FOR Bond IL-
Clinton IL-Madison IL-Monroe IL-Randolph IL-St. Clair IL-
Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1141 PM CST Sun Nov 30 2014
.UPDATE:
Issued at 934 PM CST Sun Nov 30 2014
At this point I haven`t seen much in the latest observational and
model data to suggest significant changes are need to the previous
forecast. The cold front has passed through the CWA, stretching
across far southern IL and southeast MO at 03z. Very spotty and
very weak fast moving echoes have begun to show up on regional
radars within the cold air across southern MO and southern IL, but
currently south of the freezing line. These appear to be in
response to isentropic lift over the shallow cold dome. The last
few runs of the RAP and HRRR suggest this may be the pattern the
remainder of the night and into Monday morning with these spotty
small fast-moving blips of precipitation, which will eventually be
occuring in the sub-freezing air as it continues to spread
southward. The current chance pops appear to have this adequately
covered and the only real change was to bump slightly northward
the northern periphery of slight chance pops. The two inch ground
temperature here at the WFO in Weldon Spring is 46 degrees, which
would suggest any ice issues with this spotty ZR would be on
elevated surfaces. Unless something changes, the coverage of
precipitation and associated impacts would be less than needed for
an advisory. We will continue to monitor closely through the
overnight hours should coverage become greater than currently
anticipated and then changes would be required.
Glass
&&
.SHORT TERM: (Through Monday)
Issued at 229 PM CST Sun Nov 30 2014
Main focus remains precip chances thru the period.
Mdls remain in fairly good agreement in most aspects. Still believe
the nrn extent of mdl QPF is overdone due to issues mentioned
yesterday. Mdls prog the weak s/w currently over ern TX/OK region to
move newd this evening. This s/w shud arrive over the srn MO/IL and
KY region about the same time as the 850mb cdfnt. This combination
of low and upper level forcing shud be enuf for precip to develop.
This precip shud develop around 06z tonight and persist thru much of
the night. The main question is exactly where will the precip
develop. Latest mdl guidance continues to suggest this will develop
just SE of the CWA. However, given the uncertainty with location,
will keep high chance PoPs across the far srn tier of counties.
Precip type continues to be a struggle. Precip shud begin as RA and
freeze as the cold air pushes swd thru the region. MO mesonet obs
continue to show 4 inch soil temps in the lower 50 F range across SE
MO. This shud limit ice accumulation to elevated sfcs if any does
occur. That said, these elevated sfcs may also include bridges and
overpasses if untreated. One chance from mdl soundings yesterday is
precip may linger a bit later than prev anticipated. Latest mdl
soundings suggest that if precip continues as far N as KFAM Mon
morning, IP is possible. Have added mention of IP for Mon morning
along the nrn edges of the precip shield, but kept PoPs low for this
time.
Mdls have come into better agreement regarding temps and trended twd
more of a compromise for temps thru the period.
Given the warm sfc temps and uncertainty where precip will develop
late tonight into Mon, will hold off on issuing a headline for now.
However, a headline will likely be needed if precip develops further
N than currently anticipated.
Tilly
.LONG TERM: (Tuesday through Next Sunday)
Issued at 315 PM CST Sun Nov 30 2014
Once the precip moves out of the region on Mon, the sfc ridge will
quickly move thru the region and be S of the CWA by mid day Tues.
With clouds clearing out, ample insolation shud allow temps to climb
into the 40s.
Mdls remain in fairly good agreement thru Thurs. Beyond Thurs, mdl
solns diverge. The ECMWF/GEM are in better agreement regarding mass
fields with a more amplified pattern late this week compared to the
GFS. Have therefore trended twd a ECMWF/GEM compromise. However,
have kept low PoPs lingering across much of the CWA due to the GFS
soln.
One change made from the prev few shifts is a switch from a RA or SN
forecast to a RA or FZRA forecast. Latest GFS soundings do not
support SN thru the extd portion of the forecast. Due to
inconsistencies from one run to the next and differences among mdls
thru the extd periods, have low confidence in any one mdl soln.
However, mdls do come into better agreement for Sun and into next
week as a trof ejects into the Plains. Have trended PoPs slightly
higher late in the period with better mdl agreement.
Tilly
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1141 PM CST Sun Nov 30 2014
Widely scattered showers have developed over southern half of
forecast area and are moving northeast through metro area with
freezing rain and some sleet being reported. Coverage is spotty so
for now kept tafs dry but did add tempo mention of mvfr cigs
through 10z Monday. Rest of taf sites to remain vfr. North winds
to persist with gusts at times over forecast area with vfr
conditions. Winds to become northeasterly by Monday afternoon and
diminish a bit.
Specifics for KSTL:
Widely scattered showers have developed over southern half of
forecast area and are moving northeast through metro area with
freezing rain and some sleet being reported. Coverage is spotty so
for now kept tafs dry but did add tempo mention of mvfr cigs
through 10z Monday. Otherwise, north winds to persist with gusts
at times over forecast area with vfr conditions. Winds to diminish
a bit by late Monday afternoon.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BILLINGS MT
248 PM MST MON DEC 1 2014
.SHORT TERM...VALID FOR TUE AND WED...
SURFACE TROUGH OVER CENTRAL ZONES PULLING EAST WITH TEMPERATURES
CLIMBING THROUGH THE 20S IN MOST LOCATIONS WITH A FEW EXCEPTIONS.
HIGHER ELEVATIONS ARE THE WARM SPOTS WITH AREAS WITH TIMBERCREST
RAWS AT 40 WHILE A FEW SHELTERED LOCATIONS LIKE LITTLE BIG HORN
ARE STILL IN SINGLE DIGITS. THIS DEPARTURE OF THE ARCTIC LOOKS TO
BE PERMANENT AS SPEEDY CYCLONIC FLOW ALOFT WILL BRING A SERIES OF
WEAK PACIFIC SYSTEMS ACROSS THE AREA.
WATER VAPOR SHOWS DRY AIR GETTING DRAGGED INTO THE AREA AHEAD OF
THE CYCLONIC FLOW IS LIMITING THE NORTHWARD PROGRESS OF MOISTURE
THAT IS BEING PUSHED OUT OF THE EASTERN PACIFIC BY A LOW OFF THE
CALIFORNIA COAST. THIS MOISTURE IS STREAMING INTO IDAHO AND
SOUTHWEST MONTANA AND COOKE CITY CAMS DO SHOW SOME SNOW BUT
DEWPOINTS IN THE TEENS AT DERBY MOUNTAIN AND TIMBERCREST SHOW THIS
IS ONLY IMPACTING THE BACKSIDE OF THE BEARTOOTHS AND THE
ABSAROKAS. RUC CONSISTENTLY HOLDING THIS SNOW OUT OF THE LOWER
ELEVATIONS BUT DO HAVE 4 TO 8 INCH MOUNTAIN ACCUMULATIONS EXPECTED
OVERNIGHT.
AS AXIS OF CYCLONIC FLOW SHIFTS THROUGH THE REGION TONIGHT IT DOES
ALLOW THE SURFACE TROUGH TO PULL EASTWARD AS A WEAK FRONT. HIGH
PRESSURE BEHIND THIS FRONT IS VERY LIMITED AS IT IS NOT A STRONG
AIRMASS CHANGE SO TONIGHTS TEMPERATURES WILL BE MUCH WARMER
TONIGHT THAN PREVIOUS NIGHT. THERE IS A WINDOW OF SOME GAP FLOW
WINDS IN THE LIVINGSTON AREA THIS EVENING BUT THEY WILL WANE AS
THE BOUNDARY SHIFTS SOUTH OF THE AREA.
TUESDAY ANOTHER BOUNDARY SHIFTS ACROSS THE AREA WITH A BETTER
POCKET OF HIGH PRESSURE BEHIND IT. THIS SETS UP A BREEZY DAY WITH
NORTHWEST WINDS SO DESPITE A MUCH WARMER START TEMPERATURES WILL
NOT CLIMB PAST THE 30S. HIGH RISES KICKING IN TUESDAY NIGHT
STRENGTHEN THIS HIGH AS IT MOVES INTO EASTERN MONTANA SO SURFACE
FLOW BECOMES LIGHT AND RADIATIONAL COOLING WILL BRING A SHOT AT
SINGLE DIGIT TEMPERATURES ACROSS THE EASTERN HALF OF THE AREA.
WEDNESDAY AN UPPER LEVEL RIDGE AXIS THAT HAS A BUNCH OF ENERGY
FLOWING THROUGH IT CAUSES HEIGHTS TO RISE OVER THE AREA. THIS
SUPPORTS ANOTHER BIT OF MODERATION WITH CONTINUED DRY WEATHER.
BORSUM
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
MINIMAL CHANGES THROUGH THE LONG TERM PERIOD...WITH GENERALLY
QUIET WEATHER THROUGHOUT THE PERIOD. MODELS REMAIN IN PRETTY GOOD
AGREEMENT THROUGH EARLY SATURDAY...WHERE MODELS BEGIN TO DIVERGE.
A DIRTY RIDGE DEVELOPS OVER IDAHO AND WESTERN MONTANA BY
THURSDAY...WITH A GOOD TAP PACIFIC MOISTURE STREAMING INTO THE
WESTERN MOUNTAINS. A STRONGER WAVE WILL ROTATE THROUGH
THURSDAY...GIVING A CHANCE FOR POPS INTO THE FOOTHILLS AND NEAR
WESTERN PLAINS...BUT STILL NOT EXPECTING SIGNIFICANT
ACCUMULATIONS OTHER THAN THE MOUNTAINS.
SHORTWAVE RIDGING BUILDS IN FOR FRIDAY INTO SATURDAY...POINTING TO
A MORE SIGNIFICANT WARM UP...AND DRY WEATHER. MODELS INDICATE
A STRONGER PACIFIC SYSTEM PUSHING INTO THE REGION SATURDAY
NIGHT...BUT DIFFER ON STRENGTH OF THE WAVE AND AMOUNT OF MOISTURE.
GFS SWEEPS THE WAVE ACROSS THE REGION BRINGING A CHANCE FOR PRECIP
ACROSS THE AREA THROUGH SUNDAY...WHILE EC BRINGS WEAKER WAVE...AND
SHIFT BULK OF MOISTURE TO THE NORTH. HAVE INTRODUCED SLIGHT POPS
FOR THE SATURDAY NIGHT PERIOD...BUT ONLY PLACEHOLDER...FLURRY
TYPE...POPS IN FOR SUNDAY AT THIS POINT. THE RIDGE APPEARS TO
REDEVELOP OVERNIGHT SUNDAY NIGHT...AND GENERALLY PERSISTS THROUGH
THE END OF THE PERIOD.
TEMPS IN 40S CAN BE EXPECTED THROUGHOUT THE EXTENDED
PERIOD...PEAKING WITH HIGHS NEAR 50 FOR FRIDAY AND SATURDAY. AAG
&&
.AVIATION...
GUSTY SOUTHWEST WINDS FROM BILLINGS WEST...INCLUDING BIL AND KLVM
WILL TAPER OFF OVERNIGHT AND THROUGH TUESDAY MORNING. MAINLY VFR
CONDITIONS CAN BE EXPECTED THROUGH TONIGHT ACROSS MUCH OF THE
REGION. A DISTURBANCE CROSSING THE REGION WILL BRING SNOW TO AREA
MOUNTAINS...AND EXTREME SOUTHERN AND EASTERN ROUTES
OVERNIGHT...INCLUDING KSHR AND KBHK. MOUNTAINS WILL BECOME
OBSCURED OVERNIGHT...AS SNOW DEVELOPS...AND MVFR TO IFR CONDITIONS
ARE POSSIBLE IN SNOW IN PLAINS REGIONS. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
TUE WED THU FRI SAT SUN MON
-----------------------------------------------------------
BIL 018/034 010/033 019/045 027/048 027/050 025/043 025/042
11/B 00/B 12/W 11/B 00/B 21/B 00/B
LVM 022/037 014/040 029/045 029/046 028/050 025/044 027/041
11/B 01/B 13/W 22/W 11/B 21/B 11/B
HDN 015/034 006/033 015/044 022/046 022/050 021/043 021/043
11/B 00/B 12/J 11/B 00/B 21/M 00/B
MLS 008/027 002/029 009/038 016/041 019/044 019/039 018/039
00/B 00/B 01/B 11/B 00/B 11/M 00/B
4BQ 016/033 005/034 014/042 018/044 022/044 020/041 020/039
11/B 00/B 01/B 11/U 00/B 11/M 00/B
BHK 011/025 004/028 011/035 015/040 019/040 018/035 016/036
02/J 00/U 01/B 00/B 00/B 11/M 00/B
SHR 020/036 010/038 021/045 023/046 021/049 020/044 022/042
22/J 00/B 12/W 11/B 00/B 22/W 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1200 AM EST MON DEC 1 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION OVERNIGHT WITH RAIN SHOWERS
SHIFTING FROM WESTERN INTO CENTRAL NEW YORK FOLLOWED BY MUCH
COOLER TEMPERATURES MONDAY. TEMPERATURES WILL WARM BACK TOWARDS
AVERAGE BY MIDWEEK AS A WARM FRONT LIFTS NORTH...BRINGING WITH IT A
CHANCE FOR FREEZING RAIN TUESDAY NIGHT. THE SEE SAW CONTINUES
WEDNESDAY AS ANOTHER COLD FRONT SWINGS ACROSS THE AREA...BRINGING
ANOTHER ROUND OF COOL BUT MAINLY DRY WEATHER THAT WILL LAST THROUGH
THE REMAINDER OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
A COLD FRONT EXTENDS FROM THE SAINT LAWRENCE VALLEY SOUTHWEST TO
ROCHESTER THEN ON TO COLUMBUS LATE THIS EVENING. REGIONAL RADARS
CONTINUE TO SHOW A THIN BAND OF RAIN SHOWERS JUST AHEAD OF THE FRONT
WHICH EXTENDS FROM WATERTOWN TO JUST EAST OF ROCHESTER THEN SOUTHWEST
TO COLUMBUS. THE FRONTS PARALLEL ORIENTATION WITH THE 500MB FLOW
WILL KEEP A SLOW MOVEMENT EAST ACROSS THE REGION OVERNIGHT. THE
EARLIER BLEND OF QPF FROM RECENT HRRR AND LOCAL WRF RUNS CONTINUE TO
WORK OUT VERY WELL. STILL EXPECT THE FRONT TO EASE TO EASTERN NEW
YORK BY 12Z. THE QPF BLEND YIELDS 0.10-0.25 INCH OF RAINFALL.
TEMPERATURES AHEAD OF THE FRONT CONTINUE TO RANGE THROUGH THE 50S TO
AROUND 60 LATE THIS EVENING AND ARE FALLING INTO THE 40S BEHIND THE
FRONT. THESE DROPPING TEMPS WILL CONTINUE BEHIND THE FRONT AS IT
SHIFTS EAST AND COLD ADVECTION TAKES HOLD...TEMP TRENDS REMAIN IN
LINE WITH RGEM. READINGS ACROSS WESTERN NEW YORK WILL FALL INTO THE
MID 30S BY DAYBREAK WITH LOWER 40S ACROSS THE EASTERN HALF OF THE
FORECAST AREA.
COLD AND DRY AIR WILL CONTINUE TO POUR ACROSS THE LOWER GREAT LAKES
ON MONDAY WITH EARLY MORNING HIGHS FALLING INTO THE UPPER 20S TO MID
30S...WITH COOLEST READINGS ACROSS HIGHER TERRAIN...BY LATE IN THE
DAY. THE DRY ARCTIC AIRMASS WILL PRECLUDE THE DEVELOPMENT OF ANY
SIGNIFICANT LAKE EFFECT PRECIPITATION ACROSS THE FORECAST
AREA...THOUGH LAKE-EFFECT CLOUDS WILL BE IN ABUNDANCE ALONG WITH
PERHAPS A FEW FLURRIES ACROSS UPSLOPE AREAS DOWNWIND OF BOTH LAKES.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
MONDAY NIGHT A SURFACE RIDGE OF HIGH PRESSURE WILL BE ADVANCING FROM
THE WESTERN GREAT LAKES TOWARDS SOUTHERN QUEBEC BY TUESDAY MORNING.
THIS FEATURE WILL BE RESPONSIBLE FOR DRIER AIR FLOWING ACROSS THE
EASTERN GREAT LAKES MONDAY NIGHT...AS WELL AS VEERING WINDS FROM
NORTHWEST TO NORTHEAST. A FEW LAKE EFFECT FLURRIES WITHIN THE DRYING
ATMOSPHERE EARLY MONDAY NIGHT WILL DISSIPATE ALONG THE INLAND
SOUTHERN SHORELINE THROUGH THE EVENING HOURS. OTHERWISE CLEARING
SKIES COUPLED WITH A FRESH COLD AIRMASS ASSOCIATED WITH THIS HIGH
PRESSURE WILL BRING LOWS IN THE TEENS...TO SINGLE DIGITS ACROSS THE
NORTH COUNTRY.
TUESDAY EXPECT A COLD START TO THE DAY WITH MORNING SUNSHINE FADING
BEHIND THICKENING CIRRUS THAT WILL BE APPROACHING FROM THE SOUTH.
MODELS ARE A LITTLE QUICKER WITH THE RETURN FLOW OF MOISTURE BEHIND
THIS AREA OF HIGH PRESSURE. THIS WILL LIMIT THE EARLY EVENING
COOLING SOME AND LIKELY CONFINE THE FREEZING RAIN POTENTIAL TO MORE
OF THE HILLS OF SW NYS AND THE NORTH COUNTRY. PRECIPITATION IS
EXPECTED TO ARRIVE ALONG THE LEADING EDGE OF A 55 KNOT LLJ LATER
TUESDAY NIGHT AFTER THE DRY BOUNDARY LAYER SATURATES.
BY WEDNESDAY MIDDAY SUFFICIENT WARMING ALOFT SHOULD ALLOW FOR JUST
PLAIN RAIN SHOWERS TO PASS ACROSS THE REGION...WITH CHANCES
LESSENING TOWARDS THE WEST AS A COLD FRONT SENDS THE MAIN SURGE OF
MOISTURE EASTWARD OVER EASTERN NEW YORK STATE.
WEDNESDAY NIGHT BEHIND THE COLD FRONT LAKE PARAMETERS WILL INCREASE
TO SUPPORT LAKE EFFECT SNOW ON A WESTERLY FLOW. WHILE FLURRIES MAY
FLY ACROSS SW NYS...THE WESTERLY FLOW ALONG THE LONG LAKE ONTARIO
AXIS WITH A FAIR CAPPING INVERSION OF 5K FEET MAY ALLOW FOR MINOR
LAKE EFFECT SNOW ACCUMULATIONS ON THE TUG HILL. BEHIND THE COLD
FRONT WEDNESDAY NIGHT TEMPERATURES WILL DROP BACK INTO THE 20S...BUT
WITH A ZONAL FLOW ALOFT...AND ARCTIC AIR LACKING A SIGNIFICANT DROP
IN TEMPERATURES IS NOT LIKELY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
THURSDAY A VIGOROUS SHORTWAVE WILL BE ADVANCING ACROSS SOUTHERN
CANADA...BUT SHOULD REMAIN FAR ENOUGH NORTH TO ALLOW FOR A DRY DAY
SOUTH OF LAKE ONTARIO...AND JUST SLIGHT CHANCE POPS ACROSS THE SAINT
LAWRENCE VALLEY FOR A FEW PASSING SNOW SHOWERS. ALSO SE OF LAKE ONTARIO
FLURRIES AND LIGHT LAKE EFFECT SNOW SHOWERS MAY STILL BE FALLING AT
THE START OF THE DAY...BUT AS DRIER AIR FILTERS INTO THE LAKE EFFECT
ACTIVITY...ALL SNOW SHOWERS SHOULD END THROUGH THE EARLY PART OF THE
DAY.
BEHIND THIS SHORTWAVE...A ZONAL FLOW WILL DOMINATE WITH TEMPERATURES
AVERAGING AROUND NORMAL. A SHORTWAVE WITHIN THIS ZONAL FLOW MAY
BRING A MIXTURE OF RAIN/SNOW LATER FRIDAY NIGHT AND
SATURDAY...THOUGH WITH MODEL DIFFERENCES (GFS MUCH SLOWER WITH THE
SHORTWAVE AND PRECIPITATION) WILL JUST CONTINUE WITH LOW
CHANCE/SLIGHT CHANCE POPS FOR NEXT WEEKEND.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
MVFR CIGS ARE FOUND WIDESPREAD AT 05Z WITH A COLD FRONT CROSSING
FROM WESTERN INTO CENTRAL NEW YORK. RADAR IS SHOWING A BAND OF RAIN
SHOWERS EXTENDING ALONG THE FRONT FROM KART TO EAST OF KROC TO
COLUMBUS. RAIN SHOWERS AND COLD ADVECTION HAVE BROUGHT SOME TEMPO
LOWERING OF CIGS ALTHOUGH CONFIDENCE FOR EXTENDED IFR REMAINS LOW
BASED ON OBS UPSTREAM AND BUFKIT PROFILES. FLOW IS VEERING WESTERLY
BEHIND THE FRONT WITH A NOMINAL IMPROVEMENT TO VFR...WITH MVFR
ACROSS HIGHER ELEVATIONS EXPECTED...THROUGH THE POST SUNRISE HOURS.
A SLIGHT CHANCE OF SOME WEAK LAKE EFFECT SNOW IS POSSIBLE SOUTHEAST
OF THE LAKES DURING THE DAY MONDAY. CIGS BECOME ALL VFR BY MONDAY
EVENING AS HIGH PRESSURE NOSES ACROSS THE LOWER GREAT LAKES.
OUTLOOK...
MONDAY NIGHT THROUGH TUESDAY...VFR.
WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS.
THURSDAY...VFR/MVFR.
&&
.MARINE...
WEST-NORTHWEST FLOW IS DEVELOPING BEHIND A COLD FRONT CROSSING THE
LOWER GREAT LAKES OVERNIGHT. INCREASING FETCH AND COLD ADVECTION
WILL ALLOW WAVES TO BUILD ON LAKE ONTARIO TONIGHT INTO
MONDAY...RESULTING IN WIDESPREAD SMALL CRAFT ADVISORIES ON THAT LAKE
WHILE ON LAKE ERIE THE SHORTER FETCH NORTHWESTERLY FLOW SHOULD KEEP
WINDS/WAVES JUST UNDER SCA CRITERIA.
WAVES WILL BUILD INTO THE 5 TO 7 FOOT RANGE BY LATE IN THE DAY
MONDAY ALONG THE SOUTH SHORE OF LAKE ONTARIO BEFORE DIMINISHING
LATER MONDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD. A BRIEF PERIOD
OF SMALL CRAFT CONDITIONS WILL RETURN WEDNESDAY AFTERNOON AS ANOTHER
COLD FRONT SWEEPS ACROSS THE LAKE FOLLOWED BY ANOTHER HIGH THURSDAY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR
LOZ043-044.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ042.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ045.
&&
$$
SYNOPSIS...SMITH/WOOD
NEAR TERM...SMITH/WOOD
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH/WOOD
MARINE...SMITH/WOOD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1237 AM EST MON DEC 1 2014
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE AREA FROM OFFSHORE THROUGH
MONDAY. A BACKDOOR COLD FRONT WILL MOVE THROUGH THE AREA MONDAY
NIGHT WITH HIGH PRESSURE BUILDING IN FROM THE NORTH TUESDAY THROUGH
LATE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM MON...MAINLY CLR SKIES WILL CONT WITH HIGH PRES OFF
THE CST. WINDS WILL BRIEFLY DECOUPLE AT TIMES INLAND OVERNIGHT
ALLOWING LOW TEMPS TO REACH MAINLY LOW TO MID 40S. BRZ WILL
PERSIST ALONG THE BEACHES KEEPING TEMPS UP A BIT WITH MAINLY UPR
40S TO MID 50S. WL CONT TO KEEP PATCHY FOG IN LATE SRN TIER PER
HIGH RESOLUTION MODELS LIKE THE HRRR AND NARRE SHOWING FOG/ST
DEVELOPING IN THIS AREA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM TUESDAY/...
AS OF 230 PM SUNDAY...HIGH PRESSURE OFFSHORE WILL SLOWLY SUPPRESS AS A
TROUGH APPROACHES THE APPALACHIANS BY MONDAY AFTERNOON. THIS WILL
YIELD SOUTHERLY FLOW FROM THE SURFACE TO THE UPPER LEVELS. AMPLE
DRY AIR WILL BE IN PLACE AND THE ONLY SATURATION NOTED IN THE
UPPER LEVELS...SO EXPECTING MOSTLY SUNNY CONDITIONS WITH FILTERED
CIRRUS. AS A RESULT OF BOTH CLEAR SKIES AND SOUTHERLY
FLOW...THICKNESS VALUES WILL REFLECT HIGHS IN THE MID/UPPER 60S
WITH SOME LOCATIONS TOPPING OUT AOA 70 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
AS OF 303 PM SUNDAY...A BACK DOOR FRONT WILL DROP INTO THE REGION
LATE MONDAY NIGHT INTO TUESDAY MORNING. SOME TIMING DISAGREEMENT
STILL EXISTS AMONGST MEDIUM RANGE GUIDANCE WITH GFS ABOUT 6 HOURS
FASTER THAN THE ECM/NAM SO CONTINUED FOLLOWING SUITE WITH PREVIOUS
FCST. WHILE MOST OF THE DEEPER MOISTURE AND VORTICITY REMAIN TO
OUR NORTH...WILL MAINTAIN SLIGHT CHANCE POPS THROUGH TUESDAY
ENDING TUESDAY EVENING FOR NORTHERN ZONES. TUESDAY WILL BE MUCH
COOLER THAN MONDAY AS IN- SITU CAD EVENT DEVELOPS...WITH HIGHS IN
THE 50S AREA- WIDE...STRUGGLING TO REACH 50 ACROSS THE COASTAL
PLAIN COUNTIES. SOUNDINGS AND SYNOPTIC PATTERN SUGGEST STRONG
FRONTAL INVERSION IN PLACE THROUGH THE DAY TUESDAY WITH DEEP LOW
LEVEL MOISTURE IN PLACE WITH MAINLY CLOUDY 1-1.5 K FT STRATUS
LAYER. HAVE ADDED PATCHY DRIZZLE TO GRIDS...ESP NORTHERN/WESTERN
ZONES WHERE LOW LEVEL MOISTURE IS DEEPEST. DO NOT EXPECT ANY
MEASURABLE PRECIP PER DISCUSSION ABOVE.
FROM MID THROUGH LATE NEXT WEEK...WE REMAIN IN A GENERALLY W/SW
FLOW ALOFT WITH NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES.
WEDNESDAY AND THURSDAY SHOULD BE DRY. ANOTHER WEAK SURFACE COLD
FRONT WILL CROSS THE AREA LATE THURSDAY SHIFTING WINDS NE THEN THE
COLD FRONT WASHES OUT THURSDAY NIGHT INTO FRIDAY. A SERIES OF
WEAK SHORTWAVES WILL CROSS NORTH OF THE AREA THURSDAY INTO FRIDAY
SO HAVE MAINTAINED THE SLIGHT CHANCE POPS. LATEST 30/12Z ECMWF
CONTINUES TO DEVELOP A WEAK WAVE OF LOW PRESSURE ALONG THE NC
COAST THIS WEEKEND AS A STRONG SHORTWAVE MOVES THROUGH VA/NC. MAX
TEMPS WILL BE NEAR TO SLIGHTLY ABOVE NORMAL FOR EARLY DECEMBER FRI
THROUGH THE WEEKEND...WITH READINGS GENERALLY IN THE UPPER 50S TO
LOWER 60S.
&&
.AVIATION /05Z MONDAY THROUGH FRI/...
SHORT TERM /THROUGH MONDAY NIGHT/...
AS OF 1230 AM MON...HIGH RES MODELS CONT TO SHOW ST/FOG DEVELOPING
SRN TIER LATE TONIGHT. WITH OAJ ALREADY BOUNCING DOWN A BIT WILL
HIT FOG/ST A BIT HARDER HERE WITH SOME IFR POSS AT TIMES LATE
TONIGHT. MDLS DONT SHOW MUCH FURTHER N SO WILL KEEP OTHER TAFS
VFR. HIGH CONFIDENCE IN A VFR FORECAST MID MONDAY MORNING THRU MON
EVENING AS HIGH PRES CONTS OFFSHORE WITH MCLR SKIES. LATE MON EVENING
AND OVERNIGHT A COLD FRONT WILL DROP S THRU THE REGION AND MAY SEE
SOME SUB VFR CIGS DEVELOP LATE ESPCLY INLAND AND N.
LONG TERM /TUE THROUGH FRI/...
AS OF 3 PM SUNDAY...A BACK DOOR COLD FRONT MAY LEAD TO SOME
DRIZZLE OR VERY LIGHT RAIN ON TUESDAY...THOUGH EXPECT BIGGEST
IMPACT TO AVIATION LOW STRATUS IN MVFR TO POSSIBLE ISOLATED IFR
CIGS AT TIMES. VFR EXPECTED TO RETURN AGAIN WED THROUGH LATE WEEK.
&&
.MARINE...
SHORT TERM /THROUGH MONDAY/...
AS OF 1230 AM MON...DIAMOND BUOY HAS BOUNCED UP TO 6 FEET PAST
CPL HOURS HOWEVER SEEMS LOCALIZED WITH WINDS CLOSER TO CST MUCH
LIGHTER. WINDS SHLD BE PEAKING NOW FAR OUTER WTRS SO WILL NOT
ISSUE SCA FOR CNTRL WTRS AND CONT TO MONITOR TRENDS.
PREV DISC...SWLY FLOW CAN BE EXPECTED THROUGH THE PERIOD AS THE
APPROACHING COLD FRONT CROSSES THE REGION MONDAY NIGHT. WINDS WILL
PEAK TONIGHT AND RELAX A BIT ON MONDAY. EXPECTED WINDS TONIGHT
WILL BE 15-20 KTS DIMINISHING TO TO 10-15 KTS BY MONDAY AFTERNOON.
SEAS WILL BE 2 TO 4 FT WITH SOME 5 FOOT SETS OVER THE OUTER
WATERS. SEAS WILL DIMINISH TO 2 TO 3 BY MONDAY EVENING AHEAD OF
THE COLD FRONT.
LONG TERM /MONDAY NIGHT THROUGH FRI/...
AS OF 303 PM SUNDAY...BACK DOOR COLD FRONT CROSSES THE REGION
LATE MONDAY NIGHT AND EXPECT A DRAMATIC INC IN WINDS TO NE AT
15-25 KNOTS AND SEAS BUILDING 6-7 FEET PER LOCAL NWPS/SWAN AND
SUPPORTED BY THE 00Z WAVEWATCH. GREATEST THREAT FOR SCA WILL BE
THE NORTHERN AND CENTRAL WATERS. WINDS/SEAS DIMINISH WEDNESDAY
INTO THURSDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JBM
NEAR TERM...RF
SHORT TERM...JME/LEP
LONG TERM...TL
AVIATION...RF/TL
MARINE...RF/JME/TL/LEP
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1144 PM CST SUN NOV 30 2014
.UPDATE...
ISSUED AT 1136 PM CST SUN NOV 30 2014
THE LATEST TEMP CURVE IS ON TRACK AND NO CHANGES WILL BE MADE FOR
1 AM UPDATE. SEE AVIATION DISCUSSION BELOW FOR 06Z TAFS.
UPDATE ISSUED AT 945 PM CST SUN NOV 30 2014
FORECAST CHALLENGE FOR TONIGHT WILL BE TEMPERATURES. THE BIAS
CORRECTED NAM12 00Z RUN VERIFIED WITH 03Z OBS BETTER THAN OTHER
MODELS...WITH MOST MODELS IN THE BALL PARK BUT THE HRRR A BIT
WARMER AND GFS SIGNIFICANTLY WARMER. THEREFORE WILL BUILD
NOCTURNAL CURVE FROM NAM GUIDANCE...WHICH ENDS UP BEING A BIT
WARMER IN THE FAR EAST AND COLDER IN THE NORTHWEST. MAIN IMPACT ON
HEADLINES IS IT BRINGS THE SOUTHERN TIER OF COUNTIES INTO WIND
CHILL ADVISORY CRITERIA A FEW HOURS LATER...BUT WILL KEEP
HEADLINES AS THEY ARE EXPECTING A QUICK DROP ONCE THE WINDS LET UP
SOME. TOMORROW MORNING...LANGDON AREA COULD MAKE IT INTO THE 40S
BELOW (WIND CHILL) BUT NOT WIDESPREAD ENOUGH TO WARRANT UPGRADING
SUCH A SMALL AREA TO WIND CHILL WARNING.
UPDATE ISSUED AT 658 PM CST SUN NOV 30 2014
SURFACE HIGH IS CURRENTLY OVER EASTERN MT...WITH WEST SOUTHWEST
WINDS ACROSS NORTH DAKOTA. TEMPERATURES ACROSS THE NORTH HAVE
DROPPED A FEW DEGREES BELOW FREEZING AND WITH THE BREEZY
WINDS...WIND CHILLS HAVE FALLEN TO 25 TO 30 BELOW ZERO IN PORTIONS
OF EASTERN NORTH DAKOTA. TIMING OF CURRENT HEADLINES IS IN GOOD
SHAPE AND NO CHANGES PLANNED TO ONGOING FORECAST OR HEADLINES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM CST SUN NOV 30 2014
MAIN CHALLENGES WILL BE WINDS AND TEMPS AND THE RESULTING WIND
CHILL READINGS. AS OF MID AFTERNOON SKIES HAD COMPLETELY CLEARED
OUT WITH GUSTY WEST WINDS. DESPITE HAVING A LITTLE SNOW ON THE
GROUND...THE WEST WINDS AND SUN HAVE ALLOWED TEMPS TO RISE ABOVE
ZERO JUST ABOUT EVERYWHERE. STILL EXPECTING THE WAVE NEARING THE
MANITOBA LAKES REGION TO SWING THRU THE AREA TONIGHT...BUT NOT
SEEING ANY CLOUDS ASSOCIATED WITH IT. THEREFORE WILL STICK WITH A
CLEAR FORECAST. THERE ARE SOME COLDER TEMPS ASSOCIATED WITH THE
WAVE WHICH WILL CAUSE STEADY COLD ADVECTION THRU THE EVENING.
THIS SHOULD RESULT IN STEADY WEST TO NW WINDS AT LEAST THRU
MIDNIGHT...AND POSSIBLY EVEN BEYOND. THINK AS THE SFC HIGH BUILDS
INTO SOUTHEAST ND TOWARD 12Z MON WINDS WILL FINALLY DROP OFF. THIS
WILL PROBABLY ALLOW A RAPID TEMP FALL SO WILL STICK WITH LOWS
TONIGHT IN THE 15 TO 20 BELOW ZERO RANGE. ALREADY ISSUED A WIND
CHILL ADVISORY FOR THE ENTIRE FA UNTIL MID TO LATE MON MORNING.
ONE ISSUE TO CONSIDER IS REACHING WIND CHILL WARNING CRITERIA OR
WIND CHILL READINGS 40F BELOW OR COLDER. CURRENT FORECAST SHOWS
THE NORTHWEST FA GETTING CLOSE BUT WITH UNCERTAINTIES IN HOW FAST
WINDS WILL DROP OFF AND THE RESULTING TEMPS THINK AN ADVISORY IS
GOOD FOR NOW. EXPECT LOTS OF SUN AGAIN ON MONDAY WITH WINDS
TURNING AROUND TO THE SOUTH. BY AFTERNOON INTO MON EVENING PRETTY
GUSTY SOUTH WINDS EXPECTED. COMBINATION OF WINDS AND WARM
ADVECTION WILL KEEP TEMPS WARMER MON NIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 PM CST SUN NOV 30 2014
MODELS HAD BEEN SHOWING A WEAK BAND OF LIGHT SNOW MOVING ALONG
THE ND/SD BORDER ON TUE/TUE NIGHT. GFS/ECMWF HAVE BACKED OFF ON
THIS WHILE NAM/GEM KEEP SOME SEMBLANCES OF IT AROUND. WITH THE
UNCERTAINTY NOW WILL GO WITH A DRY FORECAST. MODELS ALSO HAVE A
LITTLE LIGHT SNOW DROPPING TOWARD THE NORTHEAST FA 12Z-18Z WED.
FOR NOW KEPT IT DRY TOO AND WILL SEE WHAT LATER RUNS BRING.
WEDNESDAY NIGHT-SUNDAY...MODELS IN DECENT AGREEMENT WITH OVERALL
TRENDS. NORTHWEST FLOW ALOFT WILL TRANSITION TO ZONAL FLOW THROUGH
THIS PERIOD. NO STRONG SIGNALS FOR PRECIPITATION FROM
ANY MODEL...AND HAVE GONE WITH A DRY FORECAST. WITH THAT
SAID...THERE COULD BE A LOW PREDICTIVE EVENT...BUT THESE TYPES OF
EVENTS USUALLY HAVE MINIMAL IMPACT. TEMPERATURE WILL BE THE MAIN
CHALLENGE...LIKELY TRANSITIONING TO ABOVE NORMAL VALUES BY THE
WEEKEND (AND WITH MINIMAL SNOW COVER THE QUESTION WILL BE HOW WARM
FOR MAX TEMPS).
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1136 PM CST SUN NOV 30 2014
WINDS CONTINUE TO GUST IN THE DVL AREA AND NORTHERN VALLEY...BUT
WINDS WEST OF RUGBY ARE BEGINNING TO SUBSIDE. WILL EXTEND THE
BREEZY W SW WINDS ANOTHER TWO TO THREE HOURS. OTHER THAN
THAT...CLEAR SKIES WITH WINDS SHIFTING TO A SOUTHERLY COMPONENT
LATE MONDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ038-039-049-
052-053.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR NDZ006>008-014>016-
024-026>030-054.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ003-024-
027>032-040.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MNZ001-002-004>009-
013>017-022-023.
&&
$$
UPDATE...SPEICHER
SHORT TERM...GODON
LONG TERM...GODON/TG
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
948 PM EST TUE DEC 2 2014
.SYNOPSIS...
A WEAK DISTURBANCE WILL MOVE OUT OF THE AREA BY WEDNESDAY MORNING.
HIGH PRESSURE WILL WORK INTO THE AREA AND KEEP DRY CONDITIONS
ACROSS THE REGION THROUGH THURSDAY MORNING. ANOTHER DISTURBANCE
WILL BEGIN TO WORK INTO THE AREA THURSDAY AFTERNOON INTO THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
WEST-SOUTHWEST MID/UPR LEVEL FLOW AHD OF DIGGING TROF WORKING FROM
THE NRN PLAINS INTO THE GREAT LAKES ON WED. DEEP MOISTURE IS OFF
TO OUR EAST BUT 00Z ILN SOUNDING SHOWS LOW LEVEL MOISTURE TRAPPED BELOW
AN INVERSION AT 825 MB. IN WEAK WAA PATTERN AREA OF DRIZZLE DEVELOPED
GENERALLY ALONG AND SE OF I-71. RAP SHOWS WEAK OMEGA IN THIS LOW LEVEL
MOIST LAYER BUT THIS LIFT DIMINISHES AND SHIFTS EAST BY 06Z. HAVE
CONTINUED MENTION OF DRIZZLE AND PATCHY DENSE FOG BUT EXPECT IMPROVEMENT
OVERNIGHT. CLOUDS TO HANG TOUGH OVERNIGHT. IN WAA PATTERN WITH
SOME INCREASE IN WINDS...TEMPERATURES TO SLOWLY RISE OR STAY QUASI-STEADY
TONIGHT.
PREV DISCUSSION...
PLENTY OF LOW LEVEL MOISTURE WILL KEEP CLOUDY CONDITIONS ACROSS
THE AREA THROUGH THE NIGHT. VISIBILITIES ARE ALSO REDUCED. THERE
IS A SUBTLE BOUNDARY SOUTH OF INTERSTATE 70. SOUTH OF THIS FEATURE
AREAS OF FOG AND PATCHY DENSE FOG ARE PRESENT. NORTH OF THIS
FEATURE VISIBILITIES ARE GENERALLY THREE MILES OR HIGHER. AS THIS
BOUNDARY MOVES OUT OF THE AREA LATER THIS EVENING INTO THE
OVERNIGHT HOURS EXPECT VISIBILITIES TO IMPROVE SOME ALTHOUGH SOME
FOG IS STILL EXPECTED DURING THE OVERNIGHT HOURS. ISSUED A SPS FOR
PATCHY DENSE FOG ACROSS THE SOUTHERN HALF OF THE FA FOR A COUPLE
HOURS THIS EVENING AND ADDED FOG MENTION INTO THE HWO.
MODELS ARE INDICATING THAT SOME VERY LIGHT DRIZZLE WILL BE
POSSIBLE ACROSS THE EASTERN PORTIONS OF THE FA THIS EVENING AND
HAVE SEEN A FEW LIGHT RETURNS ON RADAR. DO NOT EXPECT THIS TO
CAUSE MUCH IN THE WAY OF DIFFICULTIES AS TEMPERATURES ARE EXPECTED
TO BE ABOVE FREEZING WHILE THE DRIZZLE IS OCCURRING. EXPECT ANY
DRIZZLE TO MOVE OUT OF THE FA BY AROUND MIDNIGHT.
TEMPERATURES ARE EXPECTED TO REMAIN FAIRLY STEADY ACROSS THE AREA
OVERNIGHT HOWEVER SOME RISES IN TEMPERATURES BY A COUPLE OF
DEGREES WILL ALSO BE POSSIBLE...PRIMARILY ACROSS SE PORTIONS OF
THE FA.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
COOLER AIR WILL WORK INTO THE FA DURING THE DAY ON WEDNESDAY.
TEMPERATURES WILL INCREASE FOR THE FIRST PART OF THE DAY HOWEVER
SOME DECREASE IN TEMPERATURES WILL BE POSSIBLE DURING THE
AFTERNOON. HIGH PRESSURE WILL WORK INTO THE AREA ALLOWING FOR DRY
CONDITIONS. CLOUD COVER WILL SLOWLY DECREASE THROUGH THE DAY AND
INTO THE EVENING HOURS ON WEDNESDAY. THIS WILL ALLOW TEMPERATURES
TO DROP OFF INTO THE 20S WEDNESDAY NIGHT.
CLOUD COVER WILL BEGIN TO INCREASE LATE WEDNESDAY NIGHT INTO THE
DAY ON THURSDAY. ISENTROPIC LIFT INCREASES AND THERE WILL BE THE
POTENTIAL FOR SOME LIGHT PRECIPITATION DEVELOPMENT ACROSS
PRIMARILY SOUTHERN PORTIONS OF THE FA THURSDAY AFTERNOON INTO THE
FIRST HALF OF THURSDAY NIGHT. BETTER PRECIPITATION CHANCES BEGIN
TO WORK INTO THE AREA BY FRIDAY MORNING. THERE IS THE POTENTIAL
FOR A BRIEF PERIOD OF A WINTRY MIX THURSDAY AFTERNOON INTO
THURSDAY NIGHT ON THE NORTHERN EDGE OF THE PRECIPITATION BEFORE
WARMER AIR WORKS INTO THE REGION AND CHANGES THE PRECIPITATION
TYPE OVER TO ALL RAIN. DECIDED NOT TO MENTION IN THE HWO AT THIS
TIME WITH SOME UNCERTAINTY ON PRECIPITATION ONSET AND HOW FAST
THE WARM AIR WILL MOVE INTO THE AREA.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
INVERTED TROUGH AND STATIONARY FRONT TAPPING INTO GULF MOISTURE WILL
BRING THE LIKELIHOOD FOR RAIN FRIDAY. A BRIEF PERIOD OF MIXED
PRECIPITATION WILL BE POSSIBLE FRIDAY MORNING BEFORE WARMER
TEMPERATURES CHANGE PRECIP TO ALL RAIN. THE LOCATION OF THE SYSTEM
SOUTH OF THE OHIO RIVER SHOULD BRING BETTER RAIN CHANCES TO THE
SOUTHERN HALF OF THE FORECAST AREA. RAIN MAY CONTINUE ON SATURDAY AS
THE SYSTEM MOVES GRADUALLY EASTWARD.
A BROAD AREA OF HIGH PRESSURE SHOULD ALLOW DRY WEATHER ON SUNDAY.
FOR MONDAY AND MONDAY NIGHT...AN UPPER TROUGH COMBINED WITH COLD
ADVECTION IN THE LOW LEVELS WILL STEEPEN LAPSE RATES ENOUGH TO
PRODUCE A CHANCE OF RAIN AND SNOW SHOWERS. MOS TEMPERATURES APPEAR
MARGINALLY COLD ENOUGH FOR SNOW BUT GUIDANCE MAY BE TOO WARM SO WENT
WITH MAINLY SNOW SHOWERS MONDAY NIGHT. HIGH PRESSURE AND A RETURN OF
DRY CONDITIONS ARE EXPECTED TUESDAY.
TEMPERATURES AS SUGGESTED BY GUIDANCE WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL...WITH HIGHS MAINLY IN THE 40S AND LOWS IN THE 30S. WENT
BELOW GUIDANCE FOR TUESDAY AS IT LOOKS LIKE WE WILL BE IN COLD
ADVECTION UNDER A NORTHERLY LOW LEVEL FLOW.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
CEILINGS OR VSBYS AT IFR CONDITIONS IN SOME AREAS WITH REST AT MVFR
CONDITIONS WITH LOW LEVEL MOISTURE AND WEAK DISTURBANCE COMBINING
WITH WAA. CONDITIONS SHOULD IMPROVE TO ALL MVFR AFTER 05Z MOST AREAS
AS WINDS BACK AND BECOME STRONGER AND DRIER AIR BEGINS TO FILTER IN.
HIGH PRESSURE WILL BUILD IN FOR DAYTIME WEDNESDAY WITH DRIER AIR
LIFTING CLOUDS WITH EVENTUAL CLEARING. WINDS SHOULD PICK UP WITH A
BIT OF GUSTINESS UNTIL EVENING.
OUTLOOK...MVFR/IFR CEILINGS AND MVFR VISIBILITIES LIKELY FRIDAY
INTO SATURDAY. MVFR CEILINGS MAY LINGER INTO SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...NOVAK
NEAR TERM...AR
SHORT TERM...NOVAK
LONG TERM...CONIGLIO
AVIATION...PADGETT
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1235 AM EST MON DEC 1 2014
.SYNOPSIS...
A SHARP COLD FRONT WILL SAG THROUGH THE OHIO VALLEY TONIGHT.
LIGHT RAIN WILL ACCOMPANY THIS FRONT FOR MOST LOCATIONS...AS WELL
AS A TWENTY DEGREE TEMPERATURE DROP IN THE FIRST FEW HOURS AFTER
IT PASSES. THE FRONT WILL SLOW A LITTLE ON ITS SOUTHWARD TREK ON
MONDAY AS IT SAGS INTO VIRGINIA AND TENNESSEE...AND WEAK
DISTURBANCES SHIFTING NORTHEAST ALONG THE FRONT MONDAY AFTERNOON AND
EVENING WILL LINGER RAIN ACROSS PORTIONS OF SOUTHERN OHIO AND
NORTHERN KENTUCKY. A LITTLE LIGHT SNOW MAY MIX IN ACROSS THIS AREA
BEFORE PRECIPITATION ENDS MONDAY NIGHT. TEMPERATURES WILL BE MUCH
COLDER ON MONDAY INTO TUESDAY...BEFORE THE FRONT RETURNS NORTHWARD
BY MIDWEEK WITH MILD AIR AND A RETURNING THREAT FOR LIGHT RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TODAY/...
LATEST SFC ANALYSIS SHOWS COLD PUSHING INTO NW OHIO FROM JUST WEST
OF TO JUST NW OF DAY. NARROW BAND OF LIGHT RAIN SHOWERS INVOF OF THIS
BOUNDARY ASSOCIATED WITH FAVORABLE LOW LEVEL MOISTURE CONVERGENCE.
THIS AXIS OF PRECIPITATION TO SAG SOUTH THRU ILN/S FA WITH THE FRONT
OVERNIGHT. HAVE ALLOWED PCPN TO EXPAND SOME NORTH OF THE BOUNDARY LATE
TONIGHT AS MORE FAVORABLE 850 MB CONVERGENCE COMES INTO PLAY.
STRONG COLD AIR ADVECTION WITH TEMPERATURES ALREADY DROPPING INTO
THE MID/UPR 40S OVER NW OHIO. HAVE MADE SLIGHT ADJUSTMENT TO HOURLY
TEMPERATURES ALLOWING FOR QUICKER PUSH OF COLD AIR. EXPECT LOWS
BY MORNING TO RANGE FORM THE LOWER 30S NW TO THE MID 40S SE.
PREV DISCUSSION...
OVERLAYING YESTERDAY/S FORECAST SOUNDINGS VALID 30.12Z AT ILN
WITH ILN RAOB AS VERIFICATION HAS SHOWN THAT NWP GUIDANCE HAS
VASTLY OVERESTIMATED MIXING RATIOS/SATURATION BELOW 900MB LAST NIGHT
THROUGH TODAY. THUS...DEPTH OF LOW LEVEL SATURATED LAYER HAS
REMAINED ABOUT 1KM TO 1.2KM DEEP FROM LATE LAST NIGHT THROUGH MUCH
OF THE DAY AND HAS KEPT DZ/RA-- PRODUCTION AT BAY THUS FAR. WOULD
MUCH PREFER TO SEE THE SATURATED LAYER EXCEED 1.5KM AND CLOSER TO
2.0KM FOR A LOW LEVEL SATURATED LAYER TO PRODUCE -DZ/RA-- IN THE
ABSENCE OF STRONGER LOW LEVEL SHORTWAVE TROUGH OR LOWER 100MB
BOUNDARY LIKE WHAT WE HAVE IN THE OPEN WARM SECTOR TODAY. CLOUD
CIGS REMAIN STUBBORNLY IN THE 2-3KFT LAYER AGL SO WE/VE BEEN
PROGRESSIVELY DELAYING MEASURABLE RAIN THREATS. THIS HAS ALLOWED
FOR EVEN WARMER READINGS /MANY LOCATIONS IN MID 60S/ AND DWPTS
HAVE CHECKED IN ABOUT 5F-7F LOWER...STRUGGLING TO BREACH
50F...THUS T/TD SPREADS ARE > 10F MOST LOCATIONS.
ALL THAT STARTING TO CHANGE HOWEVER AS SHARP/ARCTIC COLD FRONT
APPROACHES AND GLANCING BLOW FROM PARENT HEIGHT FALLS SWEEPING
ALONG THE US/CANADIAN BORDER IS FORCING A GRADUAL INCREASE IN
SYNOPTIC ASCENT ACROSS THE GREAT LAKES. KIWX WSR-88D HAS RECENTLY
DEPICTED BLOSSOMING ECHOES AHEAD OF THE COLD FRONT WHICH WAS
DEPICTED AT 30.18Z TO RUN FROM GRAND RAPIDS /MI/ TO CHICAGO TO
SPRINGFIELD /IL/. THE FURTHER SOUTH/WEST YOU TRAVEL ALONG THE
FRONT IN IL/MO/OK...THE SHARPER THE TEMP GRADIENT /30F ACROSS ONE
OR TWO COUNTIES IN SOME CASES/. HOWEVER...LACK OF BLOCKING IN THE
FAST QUASI-ZONAL FLOW WILL KEEP THE ARCTIC POOL OF BITTERLY COLD
AIR TRUCKING ON EAST /AND MODIFYING/ VS. SOUTHEAST AND THUS OUR
LOCAL AREA BECOMES MORE AND MORE REMOVED FROM THE COLDEST AIR
W/TIME. THUS...TEMP GRADIENT WILL SLOWLY RELAX ALONG THE FRONT IN
THE NEXT 12 HOURS. WILL STILL BE AN IMPRESSIVE FRONT AS IT COMES
THROUGH TONIGHT...WITH UP TO A 20 DEGREE TEMP DROP OVER 3-4 HOURS
AND A RATHER ABRUPT WIND SHIFT TO THE NORTHWEST /WITH GUSTS/. HAVE
FOLLOWED RAW 2M MODEL TEMP BLEND CLOSELY TO MITIGATE MINOR SPEED
DIFFERENCES OF FRONTAL PASSAGE. THIS PUTS FRONT TO SCIOTO COUNTY
/OH/ BY 12Z MONDAY..WITH TEMPS AT SUNRISE ON MONDAY LIKELY RANGING
FROM NEAR OR JUST BELOW FREEZING /CELINA OH/ TO THE LOW TO MID 50S
/PORTSMOUTH/.
HAVE USED A BLEND OF NCEP HI-RES WINDOW GUIDANCE /ARW AND NMM
CORES/ WITH SUBJECTIVE INTERPOLATION OF 30.17Z ESRL HRRR FOR
TIMING OF RAIN WITH FRONTAL PASSAGE TONIGHT. THESE DATA SUGGEST WE
WILL CONTINUE TO SEE SCT AREAS OF RAIN DEVELOP IMMEDIATELY AHEAD
OF THE COLD FRONT AND A FINE LINE OF LIGHT RAIN DEVELOP
ALONG/IMMEDIATELY BEHIND THE FRONT AND SWEEP THROUGH THE AREA
PARTICULARLY AFTER 00Z. RECENT RADAR TRENDS TO OUR NW SUPPORT THIS
REASONING. ALREADY SEEING SW-NE ORIENTED BANDS OF -DZ
ACRS WCNTL OH NOW IN FRONT OF PRIMARY FINE LINE ALONG FRONT.
KEEPING A 60-75% OF MEASURABLE RAIN AT MOST LOCATIONS WITH THE
FRONTAL PASSAGE TONIGHT. AM PROBABLY TO LONG /DURATION/ WITH
THREAT OF RAIN GIVEN DEPICTIONS IN SIMULATED REFLECTIVITY BUT
TRIED TO KEEP RAIN TO NO MORE THAN 2-3 HOURS AT ANY ONE LOCATION.
FRONT WILL BEGIN TO SLOW OVER KY TOMORROW AS IT SAGS SOUTH OF
STRONGER/FASTER WESTERLY FLOW...BECOMING MORE PARALLEL THE DEEP
LAYER FLOW. THIS SHOULD SERVE TO LINGER RAIN IN NORTHERN KY/FAR
SOUTHERN OHIO /APPROX SOUTH OF CINCINNATI TO CHILLICOTHE LINE/
INTO THE AFTERNOON. LITTLE CONCERNED WITH THE 30.12Z RUNS OF
GFS/ECMWF WHICH ENHANCE POST FRONTAL PCPN BANDS LATE MORNING/AFTN
ALONG AND SOUTH OF AFOREMENTIONED LINE. QPF SEEMS LIGHT...BUT BOTH
MODELS SUGGESTING 0.10 TO 0.20" QPF DEVELOPING IN RESPONSE TO MID
LEVEL FRONTOGENESIS /FGEN/ SIGNAL THAT ACCOMPANIES BRIEF WINDOW OF
RIGHT ENTRANCE ULJ FORCING THAT HAS WEAK SHORTWAVE/VORTICITY
EMBEDDED IN THIS ANTICYCLONIC PORTION OF THE UPPER JET. THIS CAUSES
CONCERN BECAUSE OF MARGINAL/CRITICAL THERMAL STRUCTURE OF THE
BOUNDARY LAYER BY THE TIME...AS CAA WILL BE STRONG AND TEMPS/DWPTS
WILL HAVE FALLEN/OR BE FALLING TO NEAR FREEZING...ESP ALONG OHIO
RIVER. CLOSER INSPECTION OF 30.12Z LAYER MAX WET BULB TEMPS
SUGGESTS 30.12Z ECMWF IS VERY BULLISH/FAST WITH THE CAA WHILE
30.12Z NAM/SREF MEAN THE SLOWEST...WITH 30.12Z GFS A MIDDLE OF THE
ROAD SOLUTION. UNFORTUNATELY 30.12Z ECMWF IS ALSO MOST ROBUST WITH
ITS LIGHT QPF DISTRIBUTION IN THE WAKE OF THE FRONT WITH THE
STRONGEST CONTRIBUTION FROM THE UPPER JET - SO THIS PRESENTS A
LOWER-END THREAT OF A PERIOD OF SNOW /VIA WET BULB PROCESSES AND
CAA/ FOR PORTIONS OF NORTHERN KY AND/OR SRN OHIO MONDAY BEFORE
PRECIPITATION WANES. HAVE NOT REALLY SEEN THIS THREAT ON PRIOR
PARALLEL GFS...OPNL NAM...OR HIGHER RES GEM/HIRES-WINDOW
RUNS...THESE PUSH FRONT FURTHER SOUTH AND THUS POST FRONTAL PCPN
BANDS DEVELOP FURTHER SOUTH AND IN WARMER AIR /RAIN/. ALSO...COARSE
30.12Z ECMWF FORECAST SOUNDINGS /NOT NATIVE MODEL RES/ SUGGESTS MID
LEVEL DRY AIR MAY INHIBIT MUCH PRECIP PRODUCTION AND PERHAPS HIGHER
QPF DEPICTION FURTHER NORTH INTO COLD AIR A FUNCTION OF COARSE GRID
RESOLUTION. SO MAIN CHANGE TO FORECAST WAS TO 1) LINGER HIGHER END
RAIN CHANCES IN THE SOUTH ON MONDAY LATE MORNING AND AFTERNOON AND
2) ALLOW FOR THIS TO MIX WITH SNOW AS A START WITHOUT ANY
ACCUMULATION. UPCOMING SHIFTS WILL NEED TO MONITOR FOR WHAT APPEARS
TO BE A LOWER END/OUTLIER THREAT FOR A STRIPE OF LIGHT/WET
ACCUMULATIONS IN OUR SOUTH ON MONDAY AFTN SHOULD A MORE ROBUST
COLDER/WETTER ECMWF SCENARIO GARNER MORE NWP SUPPORT.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
BATCH OF MID LEVEL FGEN FORCING/WEAK VORT MAX AND RIGHT ENTRANCE
REGION OF UPPER JET SHIFTS EAST LATER MONDAY NIGHT AND THUS EXPECT
A PERIOD OF DRY CONDITIONS FROM MONDAY EVENING INTO TUESDAY AS
1045MB ARCTIC HIGH PRESSURE MOVES ACROSS SERN CANADA AND OUR
SOURCE REGION AIRMASS EMANATES FROM THIS FEATURE ON NELY FLOW. A
CHILLY MONDAY NIGHT IN THE MID 20S TO AROUND 30 BEFORE BACKING
LOW AND MID LEVEL FLOW ALREADY STARTS TO ALLOW MIXING/EROSION OF
THE VERY SHALLOW ARCTIC AIRMASS BY TUESDAY. AM ALLOWING MAX TEMPS
ON TUESDAY BACK NEAR 40F BUT WAA WILL BE ONGOING ESPECIALLY JUST
OFF THE SURFACE SO THESE READINGS COULD BE A LITTLE COOL GIVEN
925MB TEMPS BY MID AFTERNOON WILL BE 0C TO +5C ALREADY IN THE
STRENGTHENING WAA REGIME. RATHER DECENT S/W TROUGH DIGGING THROUGH
MN/WI TUESDAY NIGHT /INDUCING THE BACKING FLOW OVER THE OHIO
VALLEY/ WILL ALLOW REMNANT MOISTURE/ISENTROPIC ASCENT OVER THE
SHALLOW COLD DOME TO PERHAPS PRODUCE SOME LIGHT RAIN/DRIZZLE
ESPECIALLY IN THE AREAS EAST OF I-71 TUESDAY NIGHT. BOUNDARY LAYER
TEMPS SHOULD RISE THROUGH THE NIGHT...SO HAVE KEPT ANY POTENTIAL
OF LIGHT FREEZING RAIN OUT OF THE FORECAST FOR TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
OUR REGION WILL REMAIN UNDER THE INFLUENCE OF A PROGRESSIVE ZONAL
FLOW PATTERN THROUGH AT LEAST THE END OF THE WORK WEEK...ALLOWING
FOR MOISTURE TO CONTINUE TO STREAM IN FROM THE WEST/SOUTHWEST. AS IS
TYPICAL IN A MORE PROGRESSIVE FLOW PATTERN...THE MODELS ARE
STRUGGLING WITH THEIR TIMING AND PLACEMENT OF SEVERAL EMBEDDED
SHORTWAVES. AS A RESULT...IT IS TOUGH TO RULE OUT A CHANCE OF RAIN
WEDNESDAY THROUGH FRIDAY. THE MODELS DO SEEM TO BE TRENDING TOWARD
THE BETTER MOISTURE/FORCING AFFECTING MORE OF OUR SOUTHERN FA
THOUGH...SO WILL TREND POPS ACCORDINGLY WITH THE LOWEST POPS
NORTHWEST AND THE HIGHEST IN THE SOUTHEAST. DUE TO THE TIMING ISSUES
THOUGH...WILL KEEP POPS IN CHANCE CATEGORY OR LOWER. THE LOW LEVELS
SHOULD REMAIN WARM ENOUGH TO SUPPORT PRIMARILY RAIN...BUT DEPENDING
ON THE EXACT TIMING AND PLACEMENT...SOME SNOW COULD MIX IN ACROSS
THE NORTH THURSDAY NIGHT INTO FRIDAY.
TEMPERATURES SHOULD REMAIN FAIRLY SEASONABLE THROUGH FRIDAY...WITH
HIGHS GENERALLY IN THE 40S AND OVERNIGHT LOWS MOSTLY IN THE 30S.
THE MID LEVEL FLOW PATTERN WILL BEGIN TO AMPLIFY THROUGH THE WEEKEND
WITH SOME MID LEVEL RIDGING DEVELOPING ACROSS THE OHIO VALLEY
REGION. THIS WILL ALLOW FOR SOME DRYING THROUGH THE WEEKEND ALONG
WITH SLIGHTLY WARMER TEMPERATURES.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
ALL TAF SITES ARE NOW ON THE BACK SIDE OF THE SURFACE COLD FRONT.
ADDITIONAL LIGHT PRECIPITATION WILL REMAIN POSSIBLE FOR SEVERAL
HOURS BEHIND THE FRONT...AND FOR CINCINNATI...OCCASIONAL SHOWERS
WILL LIKELY OCCUR THROUGH THE DAY ON MONDAY.
AN AREA OF IFR CEILINGS (WITH MVFR VISIBILITIES) IS MOVING INTO
THE REGION BEHIND THE FRONT. THESE CLOUDS WILL LIKELY BEGIN TO
LIFT DURING THE MID-MORNING HOURS...AND VFR CONDITIONS ARE
EXPECTED BY AFTERNOON.
WINDS BEHIND THE FRONT ARE OUT OF THE NW...AND WILL SWITCH TO THE
NORTH BY MONDAY AFTERNOON. A FEW GUSTS OF AROUND 20 KNOTS WILL BE
POSSIBLE...MAINLY FROM LATE MORNING THROUGH MID-AFTERNOON. WINDS
WILL CONTINUE A CLOCKWISE TURNING MONDAY NIGHT...WITH ENE FLOW
EXPECTED AT THE END OF THE FORECAST PERIOD.
OUTLOOK...MVFR CEILINGS ARE POSSIBLE TUESDAY INTO THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...AR
SHORT TERM...BINAU
LONG TERM...JGL
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS TULSA OK
532 AM CST MON DEC 1 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
AREAS OF LIGHT FREEZING RAIN/DRIZZLE WILL CONTINUE PRIMARILY OVER NW
AR TAF SITES THIS MORNING WITH IFR CONDITIONS/LOW CEILINGS. PRECIPITATION
SHOULD BEGIN TO SHIFT EAST BY EARLY AFTERNOON...HOWEVER LOW CLOUDS WILL
PERSIST ACROSS E OK/NW AR THIS AFTERNOON. SHOULD SEE SOME CLEARING
OVERNIGHT FROM WEST TO EAST ACROSS EASTERN OKLAHOMA TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 418 AM CST MON DEC 1 2014/
DISCUSSION...
A COLD FRONT WAS POSITIONED JUST SOUTH AND EAST OF THE CWA EARLY
THIS MORNING WITH GUSTY NORTHERLY WINDS OF 15 TO 30 MPH AND MUCH
COLDER TEMPERATURES COMMON ACROSS EASTERN OKLAHOMA AND NORTHWEST
ARKANSAS. TEMPS AS OF THIS WRITING WERE RUNNING CLOSE TO 20 TO 40
DEGREES COLDER COMPARED TO 24 HRS AGO. ALSO SOME SCATTERED LIGHT
PRECIP HAD DEVELOPED OVER FAR NORTHEAST OKLAHOMA AND NORTHWEST
ARKANSAS. A FREEZING LINE WAS LOCATED ALONG A LINE FROM NEAR
EUFAULA TO SILOAM SPRINGS TO NEAR BERRYVILLE. PRECIP NORTH OF THIS
LINE WAS FALLING AS LIGHT FREEZING DRIZZLE/FREEZING RAIN WITH SOME
POSSIBLE LIGHT SLEET MIXED IN.
PRECIP CHANCES WILL REMAIN POSSIBLE THROUGH THIS AFTERNOON...WITH
GREATER CHANCES OVER NORTHWEST ARKANSAS THIS MORNING. THE FREEZING
LINE IS EXPECTED TO CONTINUE TO SHIFT SOUTHEASTWARD THIS MORNING
WITH PARTS OF FAR EASTERN OKLAHOMA INTO FAR NORTHWEST ARKANSAS
HAVING THE POTENTIAL FOR SOME FREEZING PRECIP. LATEST HRRR AND
LOCAL IN- HOUSE MODEL TRY TO DEVELOP ADDITIONAL PRECIP OVER FAR
NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS AROUND MID MORNING
BEFORE ENDING THIS AFTERNOON. THUS...WILL LET THE WINTER WEATHER
ADVISORY RIDE AS IS...WITH THE POTENTIAL TO CANCEL EARLY IF
ADDITIONAL PRECIP DOESNT DEVELOP. TOTAL ICE ACCUMULATIONS CONTINUE
TO LOOK LIKE LESS THAN A TENTH OF AN INCH POSSIBLE OVER THE
ADVISORY AREA. PRECIP SHOULD TAPER OFF FROM WEST TO EAST THIS
AFTERNOON AND EXIT THE CWA BY THIS EVENING.
TEMPERATURES TODAY WILL STRUGGLE TO REACH UP BACK UP TO AROUND THE
FREEZING MARK ACROSS NORTHEAST/EAST CENTRAL OKLAHOMA AND ALSO FAR
NORTHWEST ARKANSAS. TEMPS OVER SOUTHEAST OKLAHOMA INTO WEST
CENTRAL ARKANSAS SHOULD CONTINUE TO DROP DURING THE MORNING HOURS
AND REMAIN NEAR STEADY THIS AFTERNOON. CLOUDY SKIES AND GUSTY
NORTHERLY WINDS WILL ALSO REMAIN COMMON THROUGH THE DAY FOR THE
CWA. GUSTY WINDS COMBINED WITH DRIER AIR FILTERING INTO THE REGION
WILL ALLOW FOR HIGH FIRE DANGERS FOR MUCH OF THE CWA AND ELEVATED
FIRE DANGERS OVER NORTHEAST OKLAHOMA. A FIRE DANGER STATEMENT HAS
BEEN ISSUED FOR NORTHEAST OKLAHOMA WHERE THE HIGHER WINDS AND
GREATER FIRE SPREAD POTENTIAL ARE EXPECTED TO BE CO-LOCATED.
OVERNIGHT TONIGHT...SKIES LOOK TO SCATTER OUT ACROSS THE WESTERN
PART OF THE CWA...WHILE CLOUDY CONDITIONS REMAIN FOR THE EASTERN
HALF. LIGHT WINDS UNDERNEATH A COLD CANADIAN HIGH PRESSURE MOVING
THROUGH THE PLAINS WILL ALLOW FOR TEMPS TONIGHT TO FALL INTO THE
20S FOR MOST LOCATIONS...WITH SOME LOCATIONS OVER NORTHEAST
OKLAHOMA POSSIBLY FALLING INTO THE TEENS.
HIGH PRESSURE EXITS THE PLAINS TUESDAY ALLOWING FOR SOUTHERLY
WINDS TO RETURN ACROSS THE CWA AND THE BEGINNING OF A TEMPERATURE
WARMING TREND BACK UP TOWARD THE SEASONAL AVERAGE FOR THE SECOND
HALF OF THE WEEK. A FRONTAL BOUNDARY IS FORECAST TO LIFT INTO THE
REGION TUESDAY NIGHT AND WEDNESDAY AND REMAIN NEARLY STATIONARY
THROUGH THE WEEK WHILE UPPER LEVEL ZONAL FLOW PUSHES A SERIES OF
WEAK SHORTWAVE THROUGH THE PLAINS. THE RESULT WILL BE AT LEAST
SLIGHT CHANCES FOR RAIN SHOWERS TO BE POSSIBLE WEDNESDAY INTO THE
WEEKEND. A SLIGHTLY MORE DEFINED WAVE MOVING THROUGH FRIDAY COULD
CREATE AN ISOLATED THUNDERSTORM OR TWO.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR OKZ068-OKZ069.
AR...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR ARZ001-ARZ002-
ARZ010-ARZ011.
&&
$$
AVIATION...12
AREA FORECAST DISCUSSION
NWS TULSA OK
418 AM CST MON DEC 1 2014
.DISCUSSION...
A COLD FRONT WAS POSITIONED JUST SOUTH AND EAST OF THE CWA EARLY
THIS MORNING WITH GUSTY NORTHERLY WINDS OF 15 TO 30 MPH AND MUCH
COLDER TEMPERATURES COMMON ACROSS EASTERN OKLAHOMA AND NORTHWEST
ARKANSAS. TEMPS AS OF THIS WRITING WERE RUNNING CLOSE TO 20 TO 40
DEGREES COLDER COMPARED TO 24 HRS AGO. ALSO SOME SCATTERED LIGHT
PRECIP HAD DEVELOPED OVER FAR NORTHEAST OKLAHOMA AND NORTHWEST
ARKANSAS. A FREEZING LINE WAS LOCATED ALONG A LINE FROM NEAR
EUFAULA TO SILOAM SPRINGS TO NEAR BERRYVILLE. PRECIP NORTH OF THIS
LINE WAS FALLING AS LIGHT FREEZING DRIZZLE/FREEZING RAIN WITH SOME
POSSIBLE LIGHT SLEET MIXED IN.
PRECIP CHANCES WILL REMAIN POSSIBLE THROUGH THIS AFTERNOON...WITH
GREATER CHANCES OVER NORTHWEST ARKANSAS THIS MORNING. THE FREEZING
LINE IS EXPECTED TO CONTINUE TO SHIFT SOUTHEASTWARD THIS MORNING
WITH PARTS OF FAR EASTERN OKLAHOMA INTO FAR NORTHWEST ARKANSAS
HAVING THE POTENTIAL FOR SOME FREEZING PRECIP. LATEST HRRR AND
LOCAL IN- HOUSE MODEL TRY TO DEVELOP ADDITIONAL PRECIP OVER FAR
NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS AROUND MID MORNING
BEFORE ENDING THIS AFTERNOON. THUS...WILL LET THE WINTER WEATHER
ADVISORY RIDE AS IS...WITH THE POTENTIAL TO CANCEL EARLY IF
ADDITIONAL PRECIP DOESNT DEVELOP. TOTAL ICE ACCUMULATIONS CONTINUE
TO LOOK LIKE LESS THAN A TENTH OF AN INCH POSSIBLE OVER THE
ADVISORY AREA. PRECIP SHOULD TAPER OFF FROM WEST TO EAST THIS
AFTERNOON AND EXIT THE CWA BY THIS EVENING.
TEMPERATURES TODAY WILL STRUGGLE TO REACH UP BACK UP TO AROUND THE
FREEZING MARK ACROSS NORTHEAST/EAST CENTRAL OKLAHOMA AND ALSO FAR
NORTHWEST ARKANSAS. TEMPS OVER SOUTHEAST OKLAHOMA INTO WEST
CENTRAL ARKANSAS SHOULD CONTINUE TO DROP DURING THE MORNING HOURS
AND REMAIN NEAR STEADY THIS AFTERNOON. CLOUDY SKIES AND GUSTY
NORTHERLY WINDS WILL ALSO REMAIN COMMON THROUGH THE DAY FOR THE
CWA. GUSTY WINDS COMBINED WITH DRIER AIR FILTERING INTO THE REGION
WILL ALLOW FOR HIGH FIRE DANGERS FOR MUCH OF THE CWA AND ELEVATED
FIRE DANGERS OVER NORTHEAST OKLAHOMA. A FIRE DANGER STATEMENT HAS
BEEN ISSUED FOR NORTHEAST OKLAHOMA WHERE THE HIGHER WINDS AND
GREATER FIRE SPREAD POTENTIAL ARE EXPECTED TO BE CO-LOCATED.
OVERNIGHT TONIGHT...SKIES LOOK TO SCATTER OUT ACROSS THE WESTERN
PART OF THE CWA...WHILE CLOUDY CONDITIONS REMAIN FOR THE EASTERN
HALF. LIGHT WINDS UNDERNEATH A COLD CANADIAN HIGH PRESSURE MOVING
THROUGH THE PLAINS WILL ALLOW FOR TEMPS TONIGHT TO FALL INTO THE
20S FOR MOST LOCATIONS...WITH SOME LOCATIONS OVER NORTHEAST
OKLAHOMA POSSIBLY FALLING INTO THE TEENS.
HIGH PRESSURE EXITS THE PLAINS TUESDAY ALLOWING FOR SOUTHERLY
WINDS TO RETURN ACROSS THE CWA AND THE BEGINNING OF A TEMPERATURE
WARMING TREND BACK UP TOWARD THE SEASONAL AVERAGE FOR THE SECOND
HALF OF THE WEEK. A FRONTAL BOUNDARY IS FORECAST TO LIFT INTO THE
REGION TUESDAY NIGHT AND WEDNESDAY AND REMAIN NEARLY STATIONARY
THROUGH THE WEEK WHILE UPPER LEVEL ZONAL FLOW PUSHES A SERIES OF
WEAK SHORTWAVE THROUGH THE PLAINS. THE RESULT WILL BE AT LEAST
SLIGHT CHANCES FOR RAIN SHOWERS TO BE POSSIBLE WEDNESDAY INTO THE
WEEKEND. A SLIGHTLY MORE DEFINED WAVE MOVING THROUGH FRIDAY COULD
CREATE AN ISOLATED THUNDERSTORM OR TWO.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 32 21 44 36 / 10 0 0 10
FSM 39 30 49 40 / 30 10 0 10
MLC 33 20 47 41 / 10 0 0 10
BVO 33 17 43 30 / 0 0 0 0
FYV 31 25 44 36 / 30 10 0 10
BYV 30 24 44 36 / 40 10 0 10
MKO 32 23 44 38 / 10 0 0 10
MIO 31 22 43 32 / 20 0 0 10
F10 32 21 45 39 / 10 0 0 10
HHW 39 27 49 42 / 20 10 0 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR OKZ068-OKZ069.
AR...WINTER WEATHER ADVISORY UNTIL 4 PM MONDAY FOR ARZ001-ARZ002-
ARZ010-ARZ011.
&&
$$
SHORT TERM...12
LONG TERM....20
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
248 AM CST MON DEC 1 2014
.DISCUSSION...
HPX RADAR IMAGERY THIS MORNING CLEARLY DEPICTS COLD FRONT WHICH
IS MOVING SOUTHEAST AROUND 15 KTS AND JUST ABOUT TO ENTER
CLARKSVILLE. SURFACE OBS SHOW TEMPERATURES HAVE BEEN FALLING A
CONSISTENT 15 DEGREES IN THE FIRST HOUR AFTER FROPA...THEN ANOTHER
5 DEGREES IN THE SECOND HOUR. THUS HIGH TEMPERATURES IN THE
NORTHWEST HALF OF THE FORECAST AREA WILL BE REACHED EARLY THIS
MORNING WITH TEMPS QUICKLY FALLING INTO THE 40S...WHILE SOUTHEAST
HALF WILL BE ABLE TO WARM INTO THE 60S PRIOR TO FROPA LATER TODAY.
CURRENT COLD FRONT SPEED OF FRONT HAS IT ARRIVING IN DOWNTOWN
NASHVILLE AROUND 11Z...ALTHOUGH FRONT IS EXPECTED TO SLOW DOWN
LATER THIS MORNING PER 00Z GUIDANCE AS UPPER SUPPORT LIFTS OFF TO
THE NORTHEAST AND BOUNDARY BECOMES MORE PARALLEL TO THE ZONAL FLOW
ALOFT. A FEW SHOWERS ALSO NOTED ALONG FRONT BUT MORE WIDESPREAD
RAIN REMAINS OFF TO THE NORTHWEST...BUT HRRR SHOWS SHOWERS WILL
INCREASE THROUGH THE DAY AS AN UPPER WAVE APPROACHES FROM THE
WEST...WARRANTING LIKELY TO CATEGORICAL POPS AREAWIDE.
MAIN FORECAST ISSUES THE REST OF THE WEEK WILL REVOLVE AROUND
TEMPERATURES AS FRONT MEANDERS BACK AND FORTH ACROSS THE MID
STATE...BUT A GENERALLY WET AND MILD PATTERN IS IN STORE WITH
TEMPS RUNNING NEAR TO ABOVE NORMAL FOR THIS TIME OF YEAR. COLD
FRONT EXPECTED TO GRIND TO A HALT TONIGHT JUST SOUTHEAST OF THE
CWA...WITH SHOWERS GRADUALLY EXITING THE CWA TO THE EAST. FRONT
LOOKS TO SLOWLY LIFT BACK NORTHWARD TUESDAY INTO WEDNESDAY AS
ANOTHER UPPER TROUGH ENTERS THE GREAT LAKES WITH A SLIGHT WARMUP
IN TEMPS...THEN MOVE BACK SOUTH ON THURSDAY AS TROUGH EJECTS TO
THE EAST WITH ANOTHER BRIEF COOLDOWN. TEMPS AND POPS WERE KEPT
NEAR THE SUPERBLEND OF ALL GUIDANCE AND CLOSE TO SURROUNDING
OFFICES.
UNUSUALLY WEAK SPLIT FLOW FOR THE BEGINNING OF WINTER DEVELOPS
ALOFT BY THE WEEKEND WITH SUBTROPICAL JET BECOMING DOMINANT OVER
OUR REGION...AND MODELS ARE REALLY STRUGGLING ON HOW TO HANDLE
THIS CONVOLUTED UPPER PATTERN. NEVERTHELESS...BOTH 00Z GFS/ECMWF
DEPICT A WEAK SHORTWAVE TROUGH MOVING ACROSS THE AREA FRIDAY AND
SATURDAY...RESULTING IN FRONT LIFTING NORTHWARD ONCE AGAIN WITH
WARMER TEMPS AND SCATTERED TO NUMEROUS SHOWERS. CANNOT EVEN RULE
OUT SOME ISOLATED THUNDERSTORMS ESPECIALLY IF THE STRONGER 00Z
ECMWF SOLUTION VERIFIES. FORECAST VERY UNCERTAIN AFTER SATURDAY AS
EURO MODEL FINALLY SHOVES FRONT OUT OF THE REGION BUT GFS WANTS
TO KEEP IT AROUND...SO KEPT LOW POPS IN THE GRIDS/ZONES ALONG WITH
SEASONABLE TEMPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 54 40 50 46 / 80 60 30 30
CLARKSVILLE 44 36 46 41 / 80 60 20 20
CROSSVILLE 62 43 56 50 / 70 70 40 50
COLUMBIA 61 41 51 46 / 70 60 30 30
LAWRENCEBURG 64 40 52 47 / 60 60 30 30
WAVERLY 47 37 48 43 / 80 60 20 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHAMBURGER
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
944 PM CST TUE DEC 2 2014
.UPDATE... ONLY A FEW EDITS WERE MADE TO GOING FORECAST WITH SLIGHT
TRIMMING BACK OF PATCHY DRIZZLE AREA TO JUST THE FAR SOUTHERN
COUNTIES NOW THROUGH MIDNIGHT. HOURLY TEMPERATURES/ DEWPOINTS WERE
ON TRACK WITH ONLY SLIGHT ADJUSTMENTS MADE FOR OBSERVATIONAL TRENDS.
&&
.DISCUSSION... LOW CLOUDS REMAIN ACROSS MUCH OF THE REGION WITH
THE SOLE EXCEPTION OF VAL VERDE COUNTY THIS EVENING. YET, EXPECT
THIS REGION TO ALSO FILL IN THROUGH THE OVERNIGHT BASED ON LATEST
SATELLITE TRENDS. BASED ON LATEST HI-RES RAP AND NAM/GFS BUFR
SOUNDINGS INDICATING DRIER AIR IN THE LOWEST 1000FT THAT WILL
LIKELY NEED TO BE OVERCOME FOR ANY LIGHT DRIZZLE TO MAKE IT ALL
THE WAY TO THE SURFACE. FORECAST SOUNDINGS DO MOISTEN UP AFTER
MIDNIGHT TOWARDS 3-6AM AND THIS COMBINED WITH WEAK ISENTROPIC
LIFT COULD HELP LIGHT PATCHY DRIZZLE DEVELOP OVER I-35 CORRIDOR
AND AREAS EAST. STILL, NO ACCUMULATIONS ARE EXPECTED WITH NO
IMPACTS ANTICIPATED. HAVE KEPT POPS LOW, IN THE 10% RANGE. UPDATED
TEXT PRODUCTS ARE OUT AND WILL CONTINUE GRAPHICS AS IS GIVEN THE
OVERNIGHT EXPECTATIONS. /ALLEN/
&&
.PREV DISCUSSION... /ISSUED 601 PM CST TUE DEC 2 2014/
AVIATION...
AVIATION CONCERNS THROUGH THE FORECAST PERIOD WILL BE CENTERED ON
LOWERING CIGS AS WELL AS SOME FOG AND DRIZZLE THROUGH THE
OVERNIGHT HOURS. CURRENTLY...MVFR CIGS ARE IN PLACE ALONG THE I-35
CORRIDOR. CIGS ARE EXPECTED TO LOWER THROUGH THE EVENING HOURS
WITH IFR CIGS BEGINNING BETWEEN 06Z-08Z. PATCHY FOG AND DRIZZLE
CAN ALSO BE EXPECTED AT THE I-35 SITES FROM ROUGHLY 09Z THROUGH
MOST OF WEDNESDAY MORNING. CIGS WILL GRADUALLY RISE TOMORROW
AFTERNOON... BUT WE/LL KEEP IFR CONDITIONS INTACT THROUGH MID-
AFTERNOON... WITH MVFR LATE AFTERNOON. OUT WEST AT KDRT...LOW
CLOUDS HAVE DISSIPATED THIS EVENING. VFR CONDITIONS CAN BE
EXPECTED FOR A FEW HOURS THIS EVENING...WITH MVFR CIGS RETURNING
AROUND 05Z. IF THE LATEST 11-3.9 SATELLITE TRENDS CONTINUE... MVFR
CIGS COULD RETURN CLOSER TO 03Z. WE/LL CONTINUE TO MONITOR AND
ADJUST AS NEEDED. CAN/T RULE OUT SOME IFR CIGS AND DRIZZLE/FOG AT
KDRT TOMORROW MORNING AND WE/LL CONTINUE THIS IN THE LATEST
FORECAST. MVFR CIGS SHOULD RETURN AFTER 03/17Z.
PREV DISCUSSION... /ISSUED 338 PM CST TUE DEC 2 2014/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
A SHALLOW COOL AIR MASS WILL ERODE OVER THE NEXT 24-36 HOURS.
AREAS OF LIGHT DRIZZLE AND SPRINKLES HAD DEVELOPED GENERALLY SOUTH
OF HIGHWAY 90 EARLIER TODAY AND THEN TAPERED OFF IN THE AFTERNOON.
THIS WEAK ISENTROPIC LIFT SHOULD RESUME LATER THIS EVENING INTO
WEDNESDAY MORNING WITH LIGHT RAIN OR SPRINKLES POSSIBLE INTO THE
AFTERNOON. THE PRECIPITATION IS NOT LIKELY TO BE CONTINUOUS...BUT
THE STEADY ZONAL FLOW PATTERN ALOFT WILL MAKE IT DIFFICULT TO PIN
DOWN THE TIMING OF BETTER RAIN CHANCES. THE THICK LOW LEVEL MOIST
LAYER SHOULD LIMIT THE POTENTIAL FOR DAYTIME HEATING...ALTHOUGH
THE RETURN OF SOUTHERLY WINDS WEDNESDAY SHOULD REDUCE THE
ISENTROPIC EFFECTS ALONG THE INVERSION AND ALLOW FOR A FEW BREAKS
IN THE CLOUDS WEDNESDAY.
LONG TERM (THURSDAY THROUGH TUESDAY)...
A DREARY PATTERN WITH LIGHT SHOWERS AND OR PATCHY DRIZZLE REMAINS
POSSIBLE THROUGH MUCH OF THE EXTENDED FORECAST AS FLOW REMAINS
ZONAL ALOFT. MOISTURE DEPTH IS EXPECTED TO INCREASE ON FRIDAY...
ESPECIALLY OVER THE COASTAL PLAINS WHERE THE NAM/GFS PWAT VALUES
APPROACH 1.5 INCHES. DPROG/DT OF THE GFS SUGGESTS SLIGHT
STRENGTHENING OF A SHORTWAVE LATE FRIDAY...AND A STRENGTHENING OF
A COLD FRONT TO FOLLOW. CHANGES AS APPLIED TO THIS FORECAST WERE
SUBTLE...WITH A SLIGHT LOWERING OF BOTH HIGHS AND LOWS OVER THE
WEEKEND. ANOTHER SHORTWAVE IS QUICK TO FOLLOW FOR SUNDAY WITH
SLIGHTLY ENHANCED RAIN CHANCES LATE SUNDAY/SUNDAY NIGHT. SHOULD
THE SHORTWAVE ACTIVITY AMPLIFY FURTHER...SOME BREAKS IN THE
OVERCAST COULD DEVELOP IN THE WAKES OF THE FRIDAY NIGHT AND SUNDAY
NIGHT DISTURBANCES.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 47 64 55 68 59 / 10 10 20 20 20
AUSTIN BERGSTROM INTL AIRPORT 46 63 54 68 59 / 10 10 20 20 20
NEW BRAUNFELS MUNI AIRPORT 48 65 56 69 61 / 10 10 20 20 20
BURNET MUNI AIRPORT 45 63 52 66 57 / 10 10 20 20 20
DEL RIO INTL AIRPORT 46 63 54 67 57 / - 10 20 10 20
GEORGETOWN MUNI AIRPORT 46 63 53 67 58 / 10 10 20 20 20
HONDO MUNI AIRPORT 47 61 55 68 59 / 10 10 20 20 20
SAN MARCOS MUNI AIRPORT 47 64 54 69 59 / 10 10 20 20 20
LA GRANGE - FAYETTE REGIONAL 49 67 55 71 61 / 10 10 20 20 20
SAN ANTONIO INTL AIRPORT 49 63 57 69 61 / 10 10 20 20 20
STINSON MUNI AIRPORT 48 64 57 69 62 / 10 10 20 20 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...15 PUBLIC SERVICE/DATA
COLLECTION...33
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1140 PM CST SUN NOV 30 2014
.AVIATION...
COLD AND DRY AIR CONTINUED TO MOVE SOUTHWARD INTO THE AREA BEHIND
THE COLD FRONT THAT PASSED KPVW AND KLBB EARLIER IN THE EVENING...
AND KCDS DURING THE AFTERNOON. SURFACE DEW-POINTS QUITE DRY AND
WILL MAKE IT DIFFICULT FOR A SIGNIFICANT LOW CLOUD LAYER TO DEVELOP
IN OUR AREA. THE SHORT RANGE HRRR SOLUTION HAS BEEN TRENDING DRIER
ALL EVENING AT THE H850 MILLIBAR LEVEL...WITH THE WRF/NAM STICKING
TO ITS GUNS ABOUT LOW CLOUDS DEVELOPING NEAR KCDS BY 06Z. SATELLITE
DOES NO SHOW LOW CLOUD DEVELOPMENT YET SO WE ARE GIVING THE LEAN
TO THE HRRR...AND HAVE REMOVED LOW CLOUD MENTION OVERNIGHT AT KCDS.
WE ALREADY HAD REMOVED LOW CLOUDS FROM KLBB AND KPVW. OTHERWISE
LOOK FOR GUSTY WINDS OVERNIGHT WITH SPEEDS TAPERING OFF MID TO
LATE MONDAY MORNING AND EVEN MORE-SO BY LATE MONDAY. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 543 PM CST SUN NOV 30 2014/
AVIATION...
COLD FRONT HAS SLOWED MOVING INTO THE DEEP WARM WESTERLY FLOW OVER
THE TEXAS SOUTH PLAINS...WITH LATEST HRRR SHOWING PASSAGE AT KPVW
BY 01Z AND KLBB SHORTLY AFTER 02Z. WE HAVE INCORPORATED THESE
SLIGHT DELAYS INTO THE LATEST TAF OUTPUT. TRENDS ALSO SUPPORT LESS
CONSIDERATION OF AN MVFR CLOUD LAYER FOR KPVW AND KLBB IN
PARTICULAR...BUT ALSO LESS CONFIDENCE FOR KCDS AS WELL. THE LOW
LEVEL AIRMASS IS PROVING SO DRY THAT EVEN THE SHARP FRONTAL LIFT
MAY BE INSUFFICIENT TO DEVELOP MUCH IN THE WAY OF LOW CLOUDS. THE
WRF/NAM HOWEVER REMAINS INSISTENT ON THIS LAYER FOR KCDS LATER
TONIGHT THROUGH MONDAY MORNING AND THE LATEST HRRR AT LEAST TRIES
TO SATURATE THIS LAYER NEAR OR JUST SOUTH OF KCDS BY 06Z-07Z. WE
WILL MAINTAIN A BROKEN 2000 FOOT LAYER ONLY FOR KCDS FOR NOW AND
REASSESS AS REALITY DEVELOPS. SURFACE GRADIENT WILL GRADUALLY
SLACKEN TOMORROW AFTER 18Z...BUT WE DID NOT ADD ANOTHER CHANGE
GROUP TO ACCOUNT FOR THIS YET. RMCQUEEN
PREV DISCUSSION... /ISSUED 328 PM CST SUN NOV 30 2014/
SHORT TERM...
WE ARE IN THE MIDST OF ANOTHER UNSEASONABLY WARM DAY AS 20Z
TEMPERATURES ARE MOSTLY IN THE 70S...WITH EVEN A FEW LOWER 80S
MIXING IN OFF THE CAPROCK. IN FACT...CHILDRESS HAS AGAIN BROKEN ITS
RECORD HIGH FOR THE DATE REACHING 81 DEGREES...TWO DEGREES ABOVE THE
PREVIOUS RECORD SET IN 1970. LUBBOCK HAS MADE IT TO 79 DEGREES SO
FAR WHICH IS A COUPLE OF DEGREES SHY OF THE RECORD SET IN 2012. AS
ADVERTISED FOR SOME TIME...THIS NEAR RECORD TO RECORD WARMTH WILL
COME TO AN ABRUPT END THIS EVENING AS A STRONG COLD FRONT PLUNGES
THROUGH. AS OF 20Z...THE COLD FRONT WAS ALREADY EDGING INTO THE
NORTHEASTERN ZONES...STRETCHING FROM DALHART TO GOODNIGHT TO MEMPHIS
TO NEAR ALTUS OKLAHOMA. THIS FRONT WAS ADVANCING STEADILY SOUTHWEST
AND IT WILL ACCELERATE THROUGH THE LATE AFTERNOON AND EVENING
HOURS...LIKELY PUSHING THROUGH LUBBOCK BETWEEN 01-03Z AND CLEARING
THE FAR SOUTHWEST ZONES BY AROUND OR SHORTLY AFTER MIDNIGHT. GIVEN
AFTERNOON TEMPERATURES BEHIND THE FRONT IN KANSAS ARE ONLY IN THE
20S...THERE WILL BE STOUT COLD AIR ADVECTION BEHIND THE FRONT.
EXPECT GUSTY NORTHEASTERLY WINDS SUSTAINED AT 15 TO 25 MPH TO BE
COMMON MUCH OF THE OVERNIGHT WITH MORNING LOWS BOTTOMING OUT IN THE
TEENS NORTH TO LOWER TO MIDDLE 20S SOUTH. THESE TEMPERATURES...
COUPLED WITH THE WINDS...WILL RESULT IN WIND CHILLS IN THE SINGLE
DIGITS FOR MANY SPOTS TOMORROW MORNING MAKING FOR BRUTAL BUT
APPROPRIATE START TO DECEMBER.
THERE REMAINS SOME UNCERTAINTY WHETHER OR NOT A SHALLOW LAYER OF
STRATUS WILL FORM WELL BEHIND THE FROPA LATE TONIGHT GIVEN STRONG
COOLING ACTING ON A RELATIVELY DRY AIRMASS. WE WOULD EXPECT AT LEAST
SOME STRATUS TO ROAM THE AREA MONDAY MORNING...LIKELY FAVORING SPOTS
OFF THE CAPROCK WHERE THERE WILL BE A LITTLE MORE MOISTURE TO WORK
WITH...THOUGH ALMOST ANYWHERE COULD SEE A SHORT BOUT OF STRATUS.
WHATEVER LOW CLOUDS FORM SHOULD GRADUALLY DIMINISH BY MIDDAY OR
EARLY AFTERNOON MONDAY...THOUGH A WEAK SHORTWAVE GLIDING BY TO THE
NORTH IN NEAR ZONAL FLOW ALOFT WILL INCREASE HIGH CLOUDS DURING THE
AFTERNOON HOURS. NO RECORD HIGHS WILL BE BROKEN TOMORROW WITH
TEMPERATURES ONLY EXPECTED TO PEAK IN THE 30S FOR MOST SPOTS. THE
BREEZY NORTH WINDS IN THE MORNING WILL GRADUALLY DIMINISH THROUGH
THE AFTERNOON AS THE PRESSURE GRADIENT RELAXES.
LONG TERM...
ONLY MINOR CHANGES MADE TO THIS LONG TERM FORECAST...AS THE FOCUS
NOW SHIFTS TO INCREASING PRECIPITATION CHANCES TOWARDS THE WEEKEND.
WHILE SOME MODEL SOLUTIONS CONTINUE TO INDICATE THAT LIGHT
RAIN COULD BEGIN AS EARLY AS LATE THURSDAY...ALL INDICATIONS ARE
THAT BEST CHANCES WILL OCCUR LATE SATURDAY THROUGH SUNDAY.
TO BEGIN THE PERIOD EARLY TUESDAY...TEMPERATURES SHOULD QUICKLY
RECOVER INTO THE 50S AND LOW 60S FOLLOWING MONDAYS COLD FRONT...AS
PRESSURE FALLS ACROSS THE HIGH PLAINS WILL FORCE THE QUICK RETURN OF
SOUTHWEST WINDS. THIS WILL ALSO DRAW INCREASING MOISTURE NORTHWARD
THROUGH THE DAY AND OVERNIGHT...AND MODEL GUIDANCE SUGGESTS THAT
THIS MAY BE ENOUGH TO RESULT IN SOME PATCHY FOG ACROSS THE
SOUTHERN SOUTH AND ROLLING PLAINS BY EARLY WEDNESDAY MORNING.
FARTHER NORTH...MORE LIMITED MOISTURE AND THE PRESENCE OF A
SUBSTANTIAL MID TO HIGH LEVEL CLOUD LAYER WILL LIKELY PROVE TO
PROHIBITIVE FOR FOG DEVELOPMENT...AND MAY EVEN LIMIT IT TO AREAS
ACROSS THE PERMIAN BASIN. STILL...ENOUGH CONFIDENCE EXISTS FOR
SOME LOW-END MENTION AT THIS TIME ACROSS THE AREAS PREVIOUSLY
MENTIONED. DURING THE DAY WEDNESDAY...YET ANOTHER SUBTLE AND
PROGRESSIVE SHORTWAVE WILL MOTOR ACROSS THE AREA...SENDING YET
ANOTHER COLD FRONT THROUGH THE REGION. ACROSS THE BOARD...LATEST
GUIDANCE HAS TRENDED A BIT STRONGER WITH THIS FRONT THAN IN
PREVIOUS SOLUTIONS...SO WE OPTED TO COOL WEDNESDAYS HIGHS A FEW
MORE DEGREES...PARTICULARLY ACROSS THE NORTHERN SOUTH AND ROLLING
PLAINS. IN ANY CASE...THIS WAVE APPEARS TO BE ANOTHER DRY ONE.
ALL EYES THEN TURN TO THE NEXT WAVE...WHICH CONTINUES TO BE HANDLED
WITH POOR AGREEMENT AMONGST MODELS DESPITE GENERAL OVERALL
IMPROVEMENT THROUGH THE REST OF THE LONG TERM PERIOD. ON ONE
HAND...THE GFS CONTINUES TO INDICATE A MORE POTENT SHORTWAVE WITH
MORE RAPID MOISTURE RETURN...AND LIKEWISE DEVELOPS LIGHT QPF ACROSS
PRIMARILY THE SOUTHERN SOUTH PLAINS AND ROLLING PLAINS AS EARLY AS
LATE THURSDAY. OVERALL...IT DOES APPEAR THAT DESPITE ITS STUBBORNNESS WITH
THIS PARTICULAR FEATURE...THE GFS SEEMS TO BE DRIFTING CLOSER TO THE
ECMWF IN ITS DEPICTION OF THE REMAINDER OF THE LONG TERM PERIOD.
THUS...WE WILL CONTINUE TO MAINTAIN A DRY FORECAST THROUGH AT LEAST
EARLY SATURDAY WHEN A MUCH MORE SUBSTANTIAL WAVE IS EXPECTED TO
IMPACT THE AREA. WHILE SLIGHT TIMING DIFFERENCES PERSIST...THE
WINDOW FOR SUBSTANTIAL PRECIPITATION SEEMS TO BE NARROWING TO A
LATE SATURDAY THROUGH SUNDAY TIME FRAME. AT 6-7 DAYS AWAY...MANY
DETAILS REMAIN UNCLEAR...BUT SLOWLY IMPROVING AGREEMENT AMONG
SOLUTIONS IS PROMISING.
FIRE WEATHER...
NEAR RECORD TEMPERATURES...HUMIDITIES OF 7 TO 13 PERCENT AND WESTERLY
WINDS SUSTAINED AT 15 TO 25 MPH WERE CREATED ELEVATED TO BRIEFLY
CRITICAL FIRE WEATHER ACROSS MOST OF THE CAPROCK THIS AFTERNOON.
CONDITIONS WILL QUICKLY IMPROVE BY EARLY EVENING AS WINDS
DIMINISH...BUT A COLD FRONT WILL PLUNGE FROM NORTHEAST TO SOUTHWEST
ACROSS THE SOUTH PLAINS THROUGH THE EVENING HOURS BRINGING AN ABRUPT
NORTHEASTERLY WIND SHIFT THAT COULD COMPLICATE ANY ONGOING FIRE
FIGHTING OPERATIONS. GUSTY NORTHEASTERLY WINDS...DRASTICALLY COLDER
TEMPERATURES AND IMPROVING HUMIDITIES WILL FOLLOW THE COLD FRONT
WITH HIGHS ON MONDAY AFTERNOON ABOUT 40-50 DEGREES COLDER THAN
TODAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 16 35 17 64 38 / 0 0 0 0 0
TULIA 16 34 19 60 39 / 0 0 0 0 0
PLAINVIEW 17 36 21 59 40 / 0 0 0 0 0
LEVELLAND 20 39 22 61 39 / 0 0 0 0 0
LUBBOCK 19 38 23 60 40 / 0 0 0 0 0
DENVER CITY 24 40 26 58 40 / 0 0 0 0 0
BROWNFIELD 23 39 25 59 40 / 0 0 0 0 0
CHILDRESS 22 36 22 58 41 / 0 0 0 0 0
SPUR 21 37 23 59 40 / 0 0 0 0 0
ASPERMONT 24 37 26 59 43 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 246 PM CST MON DEC 1 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE MOVING INTO THE NORTHERN MISSISSIPPI VALLEY EARLY THIS
AFTERNOON. WINDS ARE GRADUALLY DIMINISHING AS THIS HIGH PRESSURE
DRAWS CLOSER TO THE REGION...BUT TEMPERATURES HAVE STRUGGLED TO RISE
SO FAR TODAY. WIND CHILLS REMAIN BETWEEN 0 AND 10 DEGREES BELOW
ZERO. CLEAR SKIES EXIST ALL THE WAY ACROSS THE NORTHERN
PLAINS...BUT THE NEXT SYSTEM IS MOVING ACROSS THE PACIFIC
NORTHWEST. FORECAST CONCERNS ARE THREE FOLD...AND INCLUDE MIN TEMPS
TONIGHT...SMALL LAKE EFFECT SNOW CHANCES LATE TONIGHT INTO TUESDAY
MORNING...AND LIGHT SNOW CHANCES OVER N-C WISCONSIN FOR TUESDAY
AFTERNOON.
TONIGHT...ARCTIC HIGH PRESSURE WILL QUICKLY SLIDE ACROSS THE REGION
THIS EVENING AND HEAD TOWARDS NEW ENGLAND BY LATE TONIGHT. THOUGH
THE COLDEST AIR WILL HAVE DEPARTED THE REGION TO THE EAST...CLEAR
SKIES AND LIGHT WINDS WILL PROMOTE TUMBLING TEMPERATURES THIS
EVENING. ALWAYS DIFFICULT TO DETERMINE HOW LOW TO GO IN THESE
INSTANCES BECAUSE THE COLD SPOTS CAN QUICKLY FALL 20 DEGREES IN JUST
A FEW HOURS. UPSTREAM OBS THIS MORNING SHOWED PLENTY OF READINGS IN
THE 10 TO 15 BELOW RANGE AND THATS A GOOD START FOR THE COLD SPOTS
OF N-C WISCONSIN. AS THE SURFACE HIGH EXITS...THE SURFACE PRESSURE
GRADIENT RAPIDLY TIGHTENS AND SHOULD SEE TEMPERATURES RISE LATE IN
THE EVENING AND OVERNIGHT...WHEN CIRRUS ARRIVES.
ADDITIONALLY...SURFACE TO 950MB WINDS WILL SHIFT TO THE SOUTHEAST
OVER LAKE MICHIGAN OVERNIGHT WHICH WILL LIKELY BRING STRATO-CU AND
FLURRIES TO MUCH OF EASTERN WISCONSIN. KEPT A SMALL ACCUMULATION
OVER THE DOOR...BUT THINKING ONLY A DUSTING AT BEST DUE TO THE VERY
DRY AIRMASS IN PLACE. LOWS 0 TO 5 ABOVE OVER THE FOX VALLEY AND LAKE
SHORE.
TUESDAY...AS LAKE EFFECT CLOUDS AND FLURRIES IMPACT EASTERN
WISCONSIN...MID AND HIGH CLOUDS WILL BE SPREADING OVERHEAD DURING
THE MORNING AHEAD OF A SHEARED SHORTWAVE. THINK THE CLOUDS AND
FLURRIES WILL BECOME INCREASINGLY CONFINED TO THE LAKE SHORE AS LOW
LEVEL WINDS VEER TO THE SOUTH AND THEN SSW DURING THE MORNING. DO
NOT SEE MUCH POTENTIAL FOR SEEDER-FEEDER PROCESSES DUE TO A VERY DRY
LAYER BETWEEN 900-700MB. AS THE SHORTWAVE DRAWS CLOSER DURING THE
AFTERNOON...PROGGED SOUNDINGS OVER N-C WISCONSIN SHOW THAT DRY WEDGE
ERODING. WITH FORCING FROM DECENT MID-LEVEL FGEN...CAN SEE A LIGHT
SNOW CHANCE FOR THE NORTH BY MID AFTERNOON. WILL INCREASE PRECIP
CHANCES SOME. HIGHS RETURNING TO THE 20S.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 246 PM CST MON DEC 1 2014
WINTER IS TAKING A VACATION FOR THE NEXT WEEK OR SO
AS UPPER HEIGHTS RISE AND FLOW BECOMES ZONAL. OTHER THAN SOME
LIGHT SNOW OR FLURRIES WITH A WEAK COLD FRONT TUESDAY NIGHT IT
LOOKS LIKE IT WILL BE DRY THROUGH THE REMAINDER OF THE WEEK.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1123 AM CST MON DEC 1 2014
VFR CONDITIONS ARE ANTICIPATED THROUGH THE EVENING AS
ARCTIC HIGH PRESSURE MOVES ACROSS THE REGION. AS THIS HIGH SHIFTS
TO THE CENTRAL GREAT LAKES OVERNIGHT...WINDS WILL TURN ONSHORE OFF
LAKE MICHIGAN...WHICH WILL LIKELY PUSH MVFR STRATUS AND FLURRIES
INTO EASTERN WISCONSIN. STILL QUESTIONABLE HOW FAR INLAND THESE
CLOUDS WILL REACH...BUT THINKING MAINLY EAST OF ROUTE 41 AT THE
MOMENT. THESE CLOUDS WILL RETREAT BACK TOWARDS THE LAKE BY MIDDAY
TUESDAY. ELSEWHERE...MID AND HIGH CLOUDS WILL BE ON THE INCREASE
LATE TONIGHT THROUGH TUESDAY MORNING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 AM CST MON DEC 1 2014
.UPDATE...
ISSUED AT 1006 AM CST MON DEC 1 2014
WIND CHILLS HAVE IMPROVED THIS MORNING. THEREFORE...THE WIND
CHILL ADVISORY HAS BEEN CANCELLED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 206 AM CST MON DEC 1 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN
ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA
AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN
PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH...
MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF
THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY
ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR
LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS.
MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE
COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND
SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS
BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL
WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A
PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO
TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR
WAS STILL SITUATED OVER THE DAKOTAS.
VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH
PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS
EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH
TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH.
2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD
AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15
ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP
5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE
TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS.
EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING
TEMPERATURES TO HELP IMPROVE WIND CHILLS.
CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH
THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP
AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES
BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH
QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY
06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND
THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO
THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN
TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE
COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY
MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR
COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF
SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID
CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO
HELP TO GIVE TEMPERATURES A BOOST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 206 AM CST MON DEC 1 2014
FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD
REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA
COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE
NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z
WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD
OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO
BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED
WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT
HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER
VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE
AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP
NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND
REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW...
ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE
01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC
LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE
NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER.
HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE
SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR
THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE
EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT
PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR
FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE
PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN
BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST
A LITTLE COOLER THAN TUESDAY.
FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO
BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE
EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA
WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN
U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE
STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL
AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF
MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK
UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND
01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS
BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE
SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR
THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW
FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY
DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE
ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS
HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS
MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST.
BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS
REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT
IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH
FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME.
HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH
HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A
CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM
THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF
DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE
GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY
WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN
CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1137 AM CST MON DEC 1 2014
HIGH PRESSURE SLIDES EAST INTO THE GREAT LAKES REGION OVERNIGHT
INTO TUESDAY AS A TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE
NORTHERN PLAINS. THIS SETS UP INCREASING SOUTHERLY WINDS OVER THE
REGION LATE TONIGHT AND ESPECIALLY ON TUESDAY. EXPECT SOME
INCREASE OF MID-LEVEL ALTOCUMULUS CLOUDS AS WELL WITH BASES AOA
8-10KFT. OTHERWISE...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1006 AM CST MON DEC 1 2014
.UPDATE...
ISSUED AT 1006 AM CST MON DEC 1 2014
WIND CHILLS HAVE IMPROVED THIS MORNING. THEREFORE...THE WIND
CHILL ADVISORY HAS BEEN CANCELLED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 206 AM CST MON DEC 1 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN
ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA
AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN
PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH...
MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF
THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY
ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR
LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS.
MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE
COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND
SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS
BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL
WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A
PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO
TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR
WAS STILL SITUATED OVER THE DAKOTAS.
VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH
PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS
EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH
TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH.
2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD
AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15
ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP
5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE
TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS.
EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING
TEMPERATURES TO HELP IMPROVE WIND CHILLS.
CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH
THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP
AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES
BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH
QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY
06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND
THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO
THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN
TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE
COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY
MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR
COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF
SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID
CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO
HELP TO GIVE TEMPERATURES A BOOST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 206 AM CST MON DEC 1 2014
FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD
REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA
COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE
NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z
WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD
OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO
BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED
WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT
HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER
VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE
AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP
NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND
REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW...
ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE
01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC
LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE
NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER.
HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE
SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR
THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE
EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT
PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR
FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE
PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN
BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST
A LITTLE COOLER THAN TUESDAY.
FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO
BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE
EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA
WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN
U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE
STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL
AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF
MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK
UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND
01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS
BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE
SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR
THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW
FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY
DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE
ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS
HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS
MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST.
BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS
REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT
IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH
FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME.
HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH
HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A
CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM
THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF
DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE
GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY
WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN
CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 515 AM CST MON DEC 1 2014
GOOD VFR CONDITIONS EXPECTED TODAY/TONIGHT AS COLD AND DRY CANADIAN/
ARCTIC HIGH PRESSURE DRIFTS ACROSS THE UPPER MIDWEST. NORTHWEST
WINDS 8-12 KTS WILL GIVE WAY TO LIGHTER/VARIABLE WINDS THIS
AFTERNOON AS THE CENTER OF THE HIGH DRIFTS ACROSS THE AREA. WINDS
THEN SWING SOUTHEAST/SOUTH AND INCREASE TONIGHT AS THE HIGH MOVES
EAST OF THE REGION AND THE PRESSURE GRADIENT OVER THE AREA TIGHTENS
AHEAD OF THE NEXT LOW/TROUGH MOVES INTO THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
515 AM CST MON DEC 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 206 AM CST MON DEC 1 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN
ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA
AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN
PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH...
MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF
THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY
ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR
LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS.
MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE
COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND
SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS
BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL
WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A
PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO
TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR
WAS STILL SITUATED OVER THE DAKOTAS.
VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH
PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS
EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH
TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH.
2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD
AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15
ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP
5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE
TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS.
EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING
TEMPERATURES TO HELP IMPROVE WIND CHILLS.
CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH
THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP
AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES
BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH
QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY
06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND
THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO
THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN
TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE
COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY
MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR
COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF
SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID
CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO
HELP TO GIVE TEMPERATURES A BOOST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 206 AM CST MON DEC 1 2014
FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD
REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA
COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE
NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z
WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD
OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO
BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED
WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT
HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER
VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE
AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP
NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND
REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW...
ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE
01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC
LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE
NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER.
HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE
SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR
THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE
EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT
PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR
FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE
PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN
BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST
A LITTLE COOLER THAN TUESDAY.
FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO
BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE
EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA
WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN
U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE
STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL
AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF
MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK
UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND
01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS
BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE
SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR
THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW
FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY
DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE
ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS
HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS
MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST.
BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS
REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT
IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH
FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME.
HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH
HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A
CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM
THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF
DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE
GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY
WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN
CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 515 AM CST MON DEC 1 2014
GOOD VFR CONDITIONS EXPECTED TODAY/TONIGHT AS COLD AND DRY CANADIAN/
ARCTIC HIGH PRESSURE DRIFTS ACROSS THE UPPER MIDWEST. NORTHWEST
WINDS 8-12 KTS WILL GIVE WAY TO LIGHTER/VARIABLE WINDS THIS
AFTERNOON AS THE CENTER OF THE HIGH DRIFTS ACROSS THE AREA. WINDS
THEN SWING SOUTHEAST/SOUTH AND INCREASE TONIGHT AS THE HIGH MOVES
EAST OF THE REGION AND THE PRESSURE GRADIENT OVER THE AREA TIGHTENS
AHEAD OF THE NEXT LOW/TROUGH MOVES INTO THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ017-029-
032>034-042.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ079-086-
087-094-095.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
206 AM CST MON DEC 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 206 AM CST MON DEC 1 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHS ALONG THE BRITISH COLUMBIA COAST AND FROM NORTHERN
ONTARIO INTO CENTRAL MN....WITH WEAK RIDGING IN-BETWEEN OVER MONTANA
AND ALBERTA. SOME PACIFIC MOISTURE WAS STREAMING INTO SOUTHERN
PORTIONS OF THE FORECAST AREA AHEAD OF THE CENTRAL MN TROUGH...
MANIFESTING ITSELF AS HIGH CLOUDS. CLEAR SKIES DOMINATE THE REST OF
THE FORECAST AREA INTO THE NORTHERN PLAINS...RESULTING FROM A DRY
ARCTIC AIRMASS IN PLACE. PRECIPITABLE WATER VALUES OF 0.10 INCHES OR
LESS...20 TO 40 PERCENT OF NORMAL...WERE OBSERVED ON 00Z SOUNDINGS.
MEANWHILE...925MB TEMPS WERE IN THE -15 TO -18C RANGE. THE
COMBINATION OF THE CLEAR SKIES...DRY AIR...NIGHT TIME COOLING AND
SOME SNOWPACK HAS ALLOWED READINGS TO DIP INTO THE SINGLE DIGITS
BELOW ZERO ACROSS PORTIONS OF SOUTHEAST MN AND NORTH CENTRAL
WI...AND SINGLE DIGITS ABOVE ZERO TO MID TEENS ELSEWHERE. A
PERSISTENT 5 TO 15 MPH BREEZE HAS RESULTED IN WIND CHILLS OF ZERO
TO 15 BELOW ZERO. THE SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIR
WAS STILL SITUATED OVER THE DAKOTAS.
VERY CHILLY CONDITIONS START OFF THE FIRST DAY OF DECEMBER. ALTHOUGH
PLENTY OF SUNSHINE IS EXPECTED AS THE SURFACE HIGH OVER THE DAKOTAS
EVENTUALLY MOVES OVERHEAD BY SUNSET...925MB TEMPS IN THE -16C SOUTH
TO -20C NORTH AT 18Z WILL LIMIT TEMPERATURES FROM CLIMBING TOO MUCH.
2 METER MODEL OUTPUT AND VARIOUS MOS GUIDANCE ARE ALL IN VERY GOOD
AGREEMENT FOR TODAYS HIGHS...WITH READINGS MAINLY BETWEEN 5 AND 15
ABOVE. SHOULD THESE COME TO PASS...WE ARE LOOKING AT ONE OF THE TOP
5 COLDEST HIGHS FOR DECEMBER 1ST. WIND CHILLS WILL REMAIN AN ISSUE
TO CONTEND WITH THIS MORNING AS THE 5 TO 15 MPH BREEZE PERSISTS.
EXPECT DIMINISHING WINDS IN THE AFTERNOON COMBINED WITH CLIMBING
TEMPERATURES TO HELP IMPROVE WIND CHILLS.
CLEAR SKIES...VERY DRY AIR AND LIGHT WINDS EARLY THIS EVENING WITH
THE SURFACE HIGH IN PLACE SHOULD PROMOTE A RAPID TEMPERATURE DROP
AFTER SUNSET. SOME LOCATIONS COULD SEE A DROP OF 10 TO 15 DEGREES
BETWEEN 21-00Z. MODELS ARE IN GOOD AGREEMENT PUSHING THE HIGH
QUICKLY OFF TO THE EAST DURING THE NIGHT...MOVING INTO EASTERN WI BY
06Z AND LOWER MI BY 12Z. THIS ALLOWS THE GRADIENT TO TIGHTEN UP AND
THUS AN INCREASE OF SOUTHERLY WINDS TO BRING WARMER AIR BACK INTO
THE REGION. THE PROBLEM WE COULD RUN INTO IS WIND CHILLS BACK DOWN
TO ADVISORY CRITERIA OF -20...DUE TO THE ONSET OF THE WINDS WITH THE
COLD TEMPERATURES IN THE EVENING. THUS...ANOTHER WIND CHILL ADVISORY
MAY BE NEEDED FOR SOME AREAS AFTER THE CURRENT ONE ENDS. TAYLOR
COUNTY APPEARS TO BE THE BEST CANDIDATE FOR AN ADVISORY WITH SOME OF
SOUTHEAST MN PERHAPS NEEDING INCLUSION AS WELL. AN INCREASING MID
CLOUD DECK TOWARDS 12Z ACCOMPANYING THE WARM ADVECTION SHOULD ALSO
HELP TO GIVE TEMPERATURES A BOOST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 206 AM CST MON DEC 1 2014
FOCUS/ATTENTION FOR THE TUESDAY THROUGH WEDNESDAY TIME PERIOD
REMAINS ON THE CURRENT UPPER TROUGH ALONG THE BRITISH COLUMBIA
COAST. MODEL AGREEMENT REMAINS GOOD BRINGING THIS TROUGH ACROSS THE
NORTHERN PLAINS TUESDAY...ITS AXIS OVER THE FORECAST AREA BY 12Z
WEDNESDAY...AND OFF INTO THE EASTERN GREAT LAKES BY 00Z THU. AHEAD
OF THE TROUGH FOR TUESDAY...A BRISK SOUTHWEST WIND WILL HELP TO
BOOST 925MB TEMPS UP TO -5 TO -8C BY 00Z. THESE READINGS COMBINED
WITH SOME SUN FILTERED THROUGH PERIODS OF MID/HIGH CLOUDS SUPPORT
HIGHS IN THE 20S TO LOW 30S...WARMEST IN FAR SOUTHWEST WI AND RIVER
VALLEYS WHERE SNOW COVER IS LIMITED. AS WE HEAD INTO THE LATE
AFTERNOON AND EVENING HOURS...MODEL DISAGREEMENT BEGINS TO SHOW UP
NORTH OF I-90 IN THE PRECIPITATION DEPARTMENT. THE 01.00Z NAM AND
REGIONAL CANADIAN MODELS WANT TO PRODUCE SOME LIGHT SNOW...
ESPECIALLY NORTH OF I-94. THE 01.00Z GFS AND FOR THE MOST PART THE
01.00Z ECMWF ARE DRY. BOTH MODEL GROUPS DEPICT WEAK ISENTROPIC
LIFTING IN THE 900-600MB LAYER...BUT THE DIFFERENCE IS THAT THE
NAM/REGIONAL CANADIAN HAVE MORE MOISTURE IN THE 900-700MB LAYER.
HARD TO SAY AT THIS POINT WHAT THAT LAYER MOISTURE WILL LOOK LIKE
SO MAINTAINED SOME LOW CHANCES OF PRECIPITATION NORTH OF I-94 FOR
THE LATE AFTERNOON/EVENING HOURS. ANY SNOW SHOULD PUSH OFF TO THE
EAST AFTER 06Z AS THE UPPER TROUGH AXIS MOVES IN AND A COLD FRONT
PASSES THROUGH. THIS COLD FRONT WILL USHER IN SLIGHTLY COOLER AIR
FOR WEDNESDAY AS 925MB TEMPS FALL TO -6 TO -10C. THERE SHOULD BE
PLENTY OF SUN ON WEDNESDAY AS DRY AIR AND SUBSIDENCE MOVES IN
BEHIND THE UPPER TROUGH...SO HIGHS ARE EXPECTED TO BE NEAR OR JUST
A LITTLE COOLER THAN TUESDAY.
FROM WEDNESDAY NIGHT THROUGH FRIDAY...THE UPPER FLOW IS PROGGED TO
BECOME MORE ZONAL...WITH NORTHERN AND SOUTHERN STREAMS BECOMING MORE
EVIDENT. THE NORTHERN STREAM LOOKS TO TRACK ACROSS SOUTHERN CANADA
WHILE THE SOUTHERN STREAM BECOMES POSITIONED ACROSS THE SOUTHERN
U.S.. THE IMPACT TO THE FORECAST AREA FROM THE POSITIONS OF THESE
STREAMS IS A WARMING TREND AS PACIFIC AIR FLOWS EASTWARD...AS WELL
AS DRY CONDITIONS WITH THE SOUTHERN STREAMING BLOCKING GULF
MOISTURE. THERE IS ONE SMALL OPPORTUNITY DURING THIS PERIOD TO PICK
UP SOME LIGHT SNOW AND THAT IS ON THURSDAY FROM THE 30.00Z/12Z AND
01.00Z ECMWF. THE ECMWF SUGGESTS A DECENT SHORTWAVE AS WELL AS
BAND OF MID LEVEL FRONTOGENESIS AND MOISTURE TO HELP PRODUCE THE
SNOW. HOWEVER...ALL OTHER GUIDANCE IS DRY...SUGGESTING THE DRY AIR
THAT CAME IN ON WEDNESDAY WILL BE ENOUGH TO ABSORB ANY SNOW
FALLING OUT OF THE MID CLOUD. CONSIDERED LEAVING THURSDAY
DRY...BUT THE ECMWF CONTINUITY IS CONCERNING. THEREFORE...HAVE
ADDED A 20 PERCENT CHANCE TO LOCATIONS NORTH OF I-90. THURSDAYS
HIGHS MAY NOT BE MUCH DIFFERENT THAN WEDNESDAY DUE TO CLOUDS
MOVING IN AND WARM ADVECTION JUST BEGINNING TO GET IN EARNEST.
BETTER SHOT FOR WARMER CONDITIONS COMES FRIDAY AS 925MB TEMPS
REACH -2 TO -4C. THOSE READINGS COULD SUPPORT 30S TO LOW 40S...BUT
IT APPEARS WE WILL BE BATTLING LOW STRATUS PER ECMWF/GFS 925MB RH
FIELDS NEAR SATURATION...THUS HAVE TEMPERED HIGHS SOME.
HEADING INTO THE WEEKEND...THE SPLIT FLOW REGIME CONTINUES...WITH
HIGH PRESSURE PROGGED AT THE SURFACE. THUS...WE SHOULD SEE A
CONTINUATION OF DRY CONDITIONS. SOME DISCREPANCIES EXIST ON HOW WARM
THE WEEKEND WILL BE...AND IN PARTICULAR SATURDAY WHERE THE ECMWF
DRIVES A LITTLE BIT MORE COLD AIR INTO THE REGION COMPARED TO THE
GFS. NEVERTHELESS...READINGS SHOULD BE CLOSE TO NORMAL ON SATURDAY
WITH MORE CONFIDENCE OF ABOVE NORMAL ON SUNDAY AS 925MB TEMPS THEN
CLIMB TO AT LEAST 0C...IF NOT SLIGHTLY HIGHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1108 PM CST SUN NOV 30 2014
VFR CONDITIONS TO CONTINUE INTO MONDAY EVENING. HIGH PRESSURE OVER
THE WESTERN DAKOTAS WILL MOVE EAST ACROSS THE AREA AND INTO LOWER
MICHIGAN BY MONDAY EVENING. OTHER THAN THE HIGH CLOUDS
TONIGHT...SKIES ARE EXPECTED TO BE CLEAR FOR MONDAY. THE NORTHWEST
WINDS WILL DROP BELOW 10 KNOTS MONDAY MORNING AND THEN SWING
AROUND TO THE SOUTHEAST MONDAY EVENING ON THE BACK SIDE OF THE
HIGH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ017-029-
032>034-042.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ079-086-
087-094-095.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1135 PM CST SUN NOV 30 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 252 PM CST SUN NOV 30 2014
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A POLAR
FRONT MOVING ACROSS MICHIGAN EARLY THIS AFTERNOON. EARLIER
TEMPERATURES IN THE MIDDLE 30S OVER EASTERN WISCONSIN HAVE FALLEN
INTO THE UPPER 20S OVER MUCH OF THE FOX VALLEY. LIGHT LAKE EFFECT
SNOW SHOWERS CONTINUE TO PASS OVER N-C WISCONSIN WHERE TEMPS HAVE
HOVERED ALL DAY IN THE TEENS. LOOKING UPSTREAM...MOSTLY CLEAR
CONDITIONS RESIDE UPSTREAM OVER THE NORTHERN PLAINS THANKS TO A
STRONG HIGH PRESSURE SYSTEM BUILDING INTO THAT PART OF THE COUNTRY.
A REINFORCING ARCTIC FRONT IS DROPPING SOUTHEAST OVER THE LAKE
WINNIPEG REGION...AND IS POISED TO MOVE THROUGH THE REGION TONIGHT.
WITH THE PASSAGE OF THIS ARCTIC FRONT...WIND CHILL HEADLINES ARE THE
MAIN FORECAST CONCERN.
TONIGHT...A STRONG SHORTWAVE WILL MOVE ACROSS ONTARIO AND WILL DRIVE
AN ARCTIC FRONT ACROSS THE STATE AFTER MIDNIGHT. AHEAD OF THE
FRONT...MODELS PROJECT MID-LEVEL MOISTURE PULLING OUT TO THE
NORTHEAST AND LOW LEVEL MOISTURE EXITING WITH THE POLAR FRONT. LAKE
CLOUDS SHOULD ALSO BE RETREATING TO THE UPPER PENINSULA AS WINDS
BACK MORE WESTERLY. THIS SHOULD LEAD TO MOSTLY CLEAR CONDITIONS FOR
MUCH OF THE NIGHT. MODELS INDICATE THAT STRATO-CU COULD MOVE INTO
NORTHERN WISCONSIN BEHIND THE ARCTIC FRONT AFTER MIDNIGHT...BUT THIS
LOOKS OVERDONE BASED ON CLOUDS UPSTREAM. 925MB TEMPS WILL FALL INTO
THE -20S BEHIND THE ARCTIC FRONT BY 12Z MONDAY AND UPSTREAM OBS OVER
THE EASTERN DAKOTAS SUGGEST LOW TEMPS WILL FALL INTO THE MIDDLE
SINGLE DIGITS BELOW ZERO OVER THE NORTH. THIS MATCHES FAIRLY WELL
WITH THE AVERAGE BIAS CORRECTED GUIDANCE...AND THE PREVIOUS
FORECAST. COMBINED WITH A BRISK NORTHWEST WIND...WIND CHILLS WILL
FALL BETWEEN 20 AND 25 BELOW OVER N-C WISCONSIN. AS A RESULT...WILL
HOIST A WIND CHILL ADVISORY STARTING LATE TONIGHT.
MONDAY...COLD ADVECTION WILL CONTINUE MONDAY MORNING...AND COULD SEE
TEMPERATURES CONTINUE TO FALL OVER EASTERN WISCONSIN THROUGH
MID-MORNING. ARCTIC HIGH PRESSURE WILL THEN BUILD IN FOR THE
AFTERNOON...AND SHOULD SEE THE GUSTY NORTHWEST WINDS SUBSIDE.
THOUGH TEMPS ALOFT WILL BE MODIFYING...HIGHS WILL ONLY RANGE FROM
THE SINGLE DIGITS ABOVE ZERO TO THE LOWER TEENS UNDER PLENTY OF
SUNSHINE.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 252 PM CST SUN NOV 30 2014
UNLIKE NOVEMBER...DECEMBER LOOKS LIKE IT WILL BE
RATHER MILD AT LEAST FOR THE FIRST WEEK OR SO. THE UPPER FLOW IS
MOSTLY ZONAL WITH SURFACE HIGHS COMING FROM THE ROCKIES INSTEAD OF
THE ARCTIC. TEMPERATURES ALOFT ARE GENERALLY TOO WARM FOR
SIGNIFICANT LAKE EFFECT AND THERE ARE NO SIGNIFICANT SURFACE LOWS
FORECAST TO IMPACT THE NORTHERN GREAT LAKES.
THERE COULD BE SOME LAKE EFFECT SNOW FLURRIES OVER DOOR COUNTY
LATE MONDAY NIGHT OR EARLY TUESDAY WAS SOUTHERLY FLOW MIGHT BE
JUST COLD ENOUGH TO GET SOME SNOW SHOWERS. A WEAK COLD FRONT
MOVING THROUGH TUESDAY EVENING MIGHT PRODUCE SOME SNOW SHOWERS BUT
IT DOESN/T LOOK TO BE VERY MUCH.
IT WILL START OUT ABOUT 5 DEGREES BELOW NORMAL TUESDAY AND
WEDNESDAY BUT THEN TEMPERATURES WILL BE 5 TO 8 DEGREES ABOVE
NORMAL AFTER THAT.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1126 PM CST SUN NOV 30 2014
A SECONDARY COLD FRONT WILL BRING SOME FLURRIES AND PATCHY MVFR
CIGS TO NORTH CENTRAL WI LATE TONIGHT INTO MONDAY MORNING. LAKE
EFFECT SNOW SHOWERS WILL ALSO BE POSSIBLE OVER VILAS COUNTY. THE
FRONT WILL CAUSE BRISK NORTHWEST WINDS TO DEVELOP...WITH GUSTS TO
25 KTS POSSIBLE AT MOST LOCATIONS. THE WINDS WILL QUICKLY DECREASE
AS ARCTIC HIGH PRESSURE ARRIVES MONDAY AFTERNOON. DEVELOPING SE
WINDS MAY BRING SOME LAKE-EFFECT CLOUDS AND FLURRIES INTO THE
LAKESHORE COUNTIES BY LATE MONDAY EVENING...BUT WILL JUST MENTION
SCT LOW CLOUDS AT THE MTW TAF SITE FOR NOW.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR WIZ005-
010>012-018-019-030.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1147 PM CST TUE DEC 2 2014
.UPDATE...
1006 PM CST
UPDATE ROUND TWO...
REPORTS OF VERY LIGHT FREEZING DRIZZLE/VERY LIGHT SNOW...AKA
"SNIZZLE"...HAD BECOME MORE WIDESPREAD OVER THE PAST HOUR AND A
HALF AND INDICATED AS VERY LIGHT -5/-10 DB RETURNS IN RADAR.
ALREADY LOOKS LIKE A BACK EDGE TO THIS LIGHT SNIZZLE PASSING WEST-
EAST THROUGH CHICAGO METRO AND I-57 CORRIDORS AT 04Z/10 PM CST.
WITH GENERALLY VERY LIGHT/TRACE AMOUNTS AND IMMINENT ENDING OF
PRECIP HAVE CHOSEN NOT TO ISSUE ANY HEADLINE...THOUGH ISSUED AN
SPS TO SPREAD INFO.
OTHERWISE...SFC WINDS VEERING MORE WEST-SOUTHWEST AT THIS HOUR
WITH SOME LOW LEVEL DRYING AND EROSION OF LOW CLOUDS TO END THIS
LIGHT MIXED PRECIP SHORTLY...BECOMING MOSTLY CLEAR/PARTLY CLOUDY
OVERNIGHT.
RATZER
PREVIOUS UPDATE...
842 PM CST
MINOR CHANGES TO GOING FORECAST THIS EVENING...MAINLY TO SLOW RATE
OF TEMPERATURE FALL A BIT THIS EVENING WHERE EXTENSIVE CLOUD
COVER AND SOUTHWEST WINDS AND LOW LEVEL MOISTURE ADVECTION WAS
KEEPING TEMPS FAIRLY STEADY AHEAD OF APPROACHING COLD FRONT. OTHER
CHANGE OF NOTE WAS TO ADD A MENTION OF FLURRIES FOR THE FAR NORTHERN
TIER OF ILLINOIS COUNTIES THROUGH MIDNIGHT...WITH A FEW REPORTS OF
SNOW FLAKES REACHING THE SURFACE FROM ADJACENT DVN AND MKX COUNTIES.
WEAK SURFACE LOW PRESSURE WAVE WAS MOVING EAST ACROSS LAKE SUPERIOR
THIS EVENING...TRAILING A WEAK SURFACE TROUGH/COLD FRONT SOUTHWEST
INTO CENTRAL IOWA. EAST OF THIS BOUNDARY...SOUTHWEST LOW LEVEL WINDS
WERE LIFTING RELATIVELY MILD/MOIST LOW LEVEL AIR NORTHWARD ACROSS
THE FORECAST AREA BENEATH EXTENSIVE LOW CLOUD SHIELD. TEMPS IN THE
LOW 30S AND DEW POINTS IN THE MID 20S-AROUND 30 ARE CHARACTERISTIC
OF THE AIR MASS HERE...WITH NOTABLY DRIER AIR TO OUR WEST WHERE DEW
POINTS DIP INTO THE TEENS. ALOFT...A MID-LEVEL SHORT WAVE WAS MOVING
THROUGH THE BASE OF A BROAD UPPER TROUGH OVER THE UPPER MIDWEST...
PRODUCING LIFT AND AN AREA OF ENHANCED MID-UPPER LEVEL MOISTURE FROM
UPPER AND NORTHERN LOWER MICHIGAN BACK INTO NORTHERN IL. MODEST
RADAR RETURNS WERE NOTED AS FAR SOUTHWEST AS NORTHWEST IL...WITH DVN
REPORTING A FEW FLURRIES ACROSS THEIR NORTHERN CWA AND SEVERAL OBS
OF LIGHT SNOW ACROSS SOUTHERN WI. DVN 00Z RAOB INDICATED A
SUBSTANTIAL WARM LAYER OF +4 C AROUND 800 MB...LIKELY SAMPLED JUST
AHEAD OF BETTER MID-LEVEL MOISTURE PER IR SATELLITE LOOP...THOUGH
DOES INDICATE RATHER DRY LAYER FOR ANY PRECIP TO SURVIVE TO THE
SURFACE. BEST CHANCES APPEAR TO BE RIGHT ALONG THE WI/IL BORDER
WHERE A FEW FLURRIES MAY ACCOMPANY SOME OF THE THICKER/COLDER CLOUDS
THROUGH MIDNIGHT. NO ACCUMULATION EXPECTED.
FARTHER SOUTH...A FEW SPOTS REPORTING SOME HAZE/LIGHT FOG AND EVEN A
LITTLE VERY FINE DRIZZLE OR MIST. THIS BARELY PERCEPTIBLE HERE AT
WFO LOT AND SUSPECT IT WONT BE AN ISSUE...THOUGH WILL CONTINUE TO
MONITOR FOR ANY LIGHT FREEZING DRIZZLE POTENTIAL OVER THE NEXT FEW
HOURS BEFORE DRIER LOW LEVEL AIR ARRIVES. ILX 00Z SOUNDING SHOWS
STORY HERE...WITH SHALLOW MOIST LAYER WITH COOLEST TEMP IN LAYER
ONLY ABOUT -4 C AND DRY ABOVE INDICATING NO ICE IN COLUMN.
OTHERWISE...HAVE SLOWED TREND OF CLOUD DECREASE FROM THE WEST A BIT
AS WELL...MAINLY AFTER MIDNIGHT THROUGH EARLY WEDNESDAY MORNING.
RATZER
&&
.SHORT TERM...
256 PM CST
TONIGHT THROUGH FRIDAY...
THE THEME OF THE FORECAST IS CONTINUED SEASONABLY COOL AND
DRY...WITH PERIODS OF NEAR TO...FOR DECEMBER...SLIGHTLY ABOVE NORMAL
TEMPERATURES OVER THE WEEKEND. THE LARGE SCALE WEATHER PATTERN IS
CHARACTERIZED BY AN UPPER TROUGH OVER NORTH CENTRAL CANADA WITH
QUASI-ZONAL FLOW DRAPED ACROSS EAST CENTRAL USA. OUR NECK OF THE
WOODS IS ON THE SOUTHERN END OF THE TROUGH AXIS...WITH SOME
SHORTWAVE ENERGY RIDING THROUGH THE BASE OF THE TROUGH INTO MN/WI. A
FEW ADDITIONAL TROUGHS LIE OFF THE CALIFORNIA COAST AND OFF THE TIP
OF ALASKA. AT THE SURFACE...STRONG HIGH PRESSURE IS IN NEW ENGLAND
WHILE WEAKER HIGH PRESSURE EXTENDS OVER OUR AREA SW TO THE MID
MISSOURI VALLEY...WITH WEAK LOW PRESSURE SLIDING SOUTHEAST INTO
NORTHERN MINNESOTA.
STRATUS IS SURGING NORTHWARD AS PRESSURE LOWERS TO THE
NORTH...THOUGH THERE IS A BACK EDGE APPROACHING THE MISSISSIPPI
RIVER ON THE LEADING EDGE OF DRIER AIR IN THE PLAINS. THE ENERGY
AT THE BASE OF THE CANADIAN TROUGH WILL CONTINUE TO SLIDE EAST
TODAY. THE MOISTURE STARVED SYSTEM...PW`S UNDER 0.3 IN...WILL
CONTINUE TO RESULT IN HIGH CLOUDS AND VERY LIGHT SNOW TO OUR
NORTH. THE WEAK SURFACE LOW IN NORTHERN MINNESOTA WILL SLIDE TO
LAKE SUPERIOR TONIGHT. AS THIS OCCURS A COLD FRONT WILL APPROACH
FROM THE NW...BUT CONVERGENCE ON THE FRONT IS WEAK...SO NOT
EXPECTING MUCH OUT OF THIS. THE LOW LEVEL MOISTURE GETS SHUNTED
EAST QUICKLY WITH APPROACH OF DRIER AIR FROM THE NORTHWEST THIS
EVENING AND TONIGHT...THOUGH SOME MID AND HIGHER CLOUDS WILL DRIFT
THROUGH OVERNIGHT WITH THE TROUGH.
THE SURFACE LOW WILL DEEPEN QUITE A BIT MORE NEAR JAMES BAY ON
WEDNESDAY...BUT BY THIS TIME THE SHORTWAVE ENERGY WILL BE EAST OF
OUR AREA. WE GET A BRIEF REINFORCING SHOT OF SLIGHTLY COLDER
AIR...SHOULD SEE A BIT MORE SUNSHINE AFTER ANY LINGERING LOWER LEVEL
MOISTURE IN THE SOUTHEAST ERODES. SURFACE HIGH BUILDS IN LATE IN THE
DAY AND OVERNIGHT...RESULTING IN A CRISP AND DRY NIGHT WEDNESDAY
NIGHT.
THE SURFACE HIGH RETREATS SLOWLY ON THURSDAY AS THE FLOW ALOFT TURNS
ZONAL AGAIN. THE TROUGH OFF THE CALIFORNIA COAST DISSOLVES...BUT
SOME WEAK ENERGY ASSOCIATED WITH IT RAPIDLY MOVES EASTWARD.
MOISTURE TRANSPORT INCREASES IN THE SOUTHWEST FLOW AHEAD OF THIS
DISTURBANCE. ISENTROPIC LIFT REALLY DOES NOT GET GOING INTO THURSDAY
NIGHT AND MORE SO FRIDAY...SO REMOVED SLIGHT CHANCE MENTION FOR
THURSDAY. LOOKS LIKE BEST ISENTROPIC LIFT COINCIDES WITH MOISTURE TO
OUR SOUTH...AND THE ECMWF CONTINUES A CONSISTENT TREND OF PRECIP
REMAINING SOUTH OF I-80. KEPT SOME SMALL POPS NORTH WITH THE GFS
HOLDING ONTO SOME PRECIP...BUT FEEL THAT MUCH OF THIS WILL SLIDE BY
TO THE SOUTH AS WE HANG ONTO A DRIER NE FLOW.
KMD
&&
.LONG TERM...
256 PM CST
SATURDAY THROUGH TUESDAY...
IT APPEARS TO BE A BENIGN AND MILDER PATTERN FOR THE WEEKEND. QUIET
WESTERLY FLOW ALOFT AND SURFACE HIGH PRESSURE IN CONTROL. NORTHEAST
FLOW WILL KEEP THINGS A BIT COOLER...THEN HIGH PRESSURE SHIFTS
SOMEWHAT EAST SUNDAY. HIGH PRESSURE ALOFT OFF IN THE ATLANTIC KEEPS
THE CANADIAN TROUGH AT BAY...AND THEREFORE ALLOWS SHORTWAVE ENERGY
CURRENTLY OFF THE ALASKA COAST TO PUSH SOUTHWEST OUT OF THE CANADIAN
ROCKIES IN A CLIPPER-LIKE MANNER SUNDAY NIGHT INTO MONDAY. MODELS
ARE MIXED AS TO WHETHER WE GET ANY PRECIP WITH THIS WITH THE
"WETTER" GFS JUST GRAZING THE AREA WITH SOME LIGHT RAIN TURNING TO
POSSIBLY SNOW...WHILE THE EC IS DRY WITH THE ENERGY HEADING NORTH.
THE PATTERN LOOKS TO AMPLIFY SOME BY EARLY TO MID NEXT WEEK...BUT
NOT UNTIL AFTER A PERIOD OF DRY AND COOLER NORTHERLY FLOW TO START
THE WEEK. EVENTUALLY THIS WILL ALLOW A RIDGE IN THE WEST TO MAKE
SOME HEADWAY EASTWARD BUT THIS APPEARS TO HAVE SLOWED A LITTLE BIT.
MODELS HAVE MODERATE PREDICTABILITY ON THIS FEATURE AT THIS TIME
WHICH WOULD BRING DRY AND MILDER WEATHER.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* BRIEF MVFR AT VERY START OF TAF PERIOD.
LENNING
//DISCUSSION...UPDATED 06Z...
IFR AND MVFR CIGS ARE VERY QUICKLY MOVING OUT SO ELECTED NOT TO
INCLUDE THEM IN TAFS FOR THE IL SIDE...BUT CARRIED THEM FOR AN
HOUR AT GYY. WITH APPROACHING HIGH PRESSURE...WSW WINDS GRADUALLY
VEER NORTHWESTERLY AND REMAIN RELATIVELY LIGHT...AND SKIES CLEAR
OUT.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE FOR ALL ELEMENTS.
LENNING
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY...VFR/WX NIL. ELY TO SELY WINDS.
FRIDAY...SLIGHT CHANCE RAIN. MVFR POSSIBLE. SELY BECMG NELY
WINDS.
SATURDAY...SLIGHT CHANCE RAIN EARLY. MVFR POSSIBLE. NELY WINDS
BECMG ELY.
SUNDAY...SLIGHT CHANCE RAIN/SNOW LATE. IFR POSSIBLE LATE. SELY WINDS
BECMG WLY.
MONDAY...SLIGHT CHANCE RAIN/SNOW EARLY. IFR POSSIBLE EARLY. SELY WINDS
BECMG WLY.
KREIN
&&
.MARINE...
123 PM CST
HIGH PRESSURE TO THE EAST OF THE LAKE AND A TROUGH OF LOW PRESSURE
APPROACHING FROM THE WEST HAS ALLOWED FOR SOUTHERLY WINDS
TODAY...WITH HIGHEST SPEEDS TO 30 KT BEING OBSERVED OVER THE
NORTHERN HALF OF THE LAKE. THESE SAME SPEEDS WILL LIKELY CONTINUE
TONIGHT BUT WITH WINDS BECOMING MORE WESTERLY AS THIS TROUGH AND
FRONTAL BOUNDARY MOVE ACROSS THE LAKE THROUGH WEDNESDAY MORNING.
SPEEDS WILL BRIEFLY COME DOWN WEDNESDAY MORNING WITH THE DEPARTURE
OF THIS TROUGH...BUT WILL INCREASE IN THE AFTERNOON AS HIGH
PRESSURE BUILDS SOUTHEAST ACROSS THE REGION. EXPECT ANOTHER PERIOD
OF TO 30 KT WINDS OVER THE ENTIRE LAKE WEDNESDAY AFTERNOON INTO
THE NIGHT...BEFORE WINDS DIMINISH INTO THURSDAY MORNING AS THIS
HIGH MOVES OVERHEAD. THIS HIGH WILL SHIFT TO THE EAST THURSDAY
INTO THURSDAY NIGHT...WITH A PERIOD OF SOUTHERLY FLOW EXPECTED
THROUGH THE END OF THE WORK WEEK.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 4 AM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1117 PM CST Tue Dec 2 2014
.UPDATE...
ISSUED AT 845 PM CST TUE DEC 2 2014
Backedge of clouds over west central Illinois continues to make
steady progress to the east this evening. We expect this trend
to continue during the overnight hours with most of the short
term models indicating the backedge of the clouds should push
into far east central Illinois by dawn Wednesday. A weak front
to our northwest will push across our area Wednesday morning
with little in the way of sensible weather other than a wind
shift into the west and northwest as high pressure builds east
into the Midwest for the remainder of the day. Will have the
updated zones out by 900 pm.
&&
.SHORT TERM...(Tonight)
ISSUED AT 310 PM CST TUE DEC 2 2014
20z/2pm surface analysis shows ridge axis extending from the Great
Lakes to Texas. Despite presence of high pressure, low-level
moisture remains trapped beneath a strong subsidence inversion
evident on latest LAPS soundings, which has resulted in overcast
conditions across central Illinois this afternoon. Visible
satellite imagery shows back edge of clouds slowly eroding across
central Missouri, with satellite timing tools bringing the clearing
into the western KILX CWA by mid-evening. Latest HRRR has a similar
trend, suggesting clearing skies from west to east by mid to late
evening. Based on satellite trends and expected southwesterly
return flow on the back side of the departing high, think skies will
become mostly clear across locations along/northwest of a
Taylorville to Champaign line by midnight. Further southeast, cloud
cover will be much slower to exit, with soundings indicating mostly
cloudy skies through the entire night across the far E/SE CWA. Due
to the initial cloud cover and a light southwesterly wind, have gone
2 to 3 degrees above MAV guidance for lows tonight, with readings
ranging from the lower 20s far northwest around Galesburg to the
lower 30s far southeast.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 310 PM CST TUE DEC 2 2014
Morning upper air and moisture channel satellite data shows minor
upper wave moving east across the northern US, approaching Great
Lakes. This system will drag a weak cold front into IL region on
early on Wednesday, coming through dry and bringing high pressure in
behind it.
Main system to affect area is currently off the west coast. Forecast
models bring a wave east from the offshore low, it tracking east
over the western state through day Thursday. southerly low level
flow expected to develop Thursday in response to the system exiting
the Rockies. Overrunning flow will develop precipitation by late
Thursday, but will not reach region till Thursday night, so dropped
Thursday pcpn. Pops spreading into the CWA Thursday night. With
temperature though near freezing, possibly some freezing rain in the
central and north central parts of IL Thursday night, before
temperatures rise Friday morning with the bulk of pcpn on Friday and
Friday night.
Track of the developing surface low is still a little uncertain, as
GFS brings low across KY and EUR across northern AL. Pcpn to
gradually pull out on Saturday, and will be faster if EUR solution
is right.
Weak northern stream system to again move over Great Lakes on
Monday, but have kept forecast dry at this time, again due to the
differences in the models on track and moisture.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1110 PM CST TUE DEC 2 2014
Band of MVFR cigs continues to steadily track east across the
forecast area with the backedge just clearing the I-55 corridor
from KSPI thru KBMI. Based on the present movement it appears
KDEC should see the clearing trend between 0600Z and 0700Z and
over at KCMI btwn 0700z and 0800z. Still a bit concerned about
areas near and to the east of I-57 as satellite trends indicate
a bit of a slow down to the eastward trajectory of the clouds.
We should see VFR conditions across the area on Wednesday as
high pressure settles in from the northwest. Surface winds will
be southwest to west at around 10 kts overnight and as a trof
shifts thru the area, we expect winds to turn more into a west
to northwest direction on Wednesday with speeds averaging from
10 to 15 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS JACKSON KY
212 AM EST WED DEC 3 2014
.UPDATE...
ISSUED AT 211 AM EST WED DEC 3 2014
PESKY FRONTAL BOUNDARY AND WAVES OF LOW PRESSURE CONTINUE TO PLAGUE
EASTERN KY TONIGHT. WSR- 88D RADAR INDICATES SHOWERS RIDING NE ALONG
THE SE BORDER OF TN/VA TONIGHT. HI- RES MODELS BACK THIS GENERAL
TREND OVERNIGHT. OTHERWISE FOG AND DRIZZLE WILL CONTINUE TO BE SEEN
AT TIMES ACROSS THE REGION GIVEN LOW LEVEL MOISTURE IN PLACE. ALSO
FRESHENED GRIDS WITH LATEST OBS AND TRENDS.
UPDATE ISSUED AT 1105 PM EST TUE DEC 2 2014
DID A QUICK UPDATE TO REFINE THE FORECAST T/TD GRIDS THROUGH THE REST
OF THE NIGHT. DID ALSO LOOK AHEAD TO WEDNESDAY NIGHT AND DECIDED TO
NIX THE IDEA OF SNOW BASED ON SOUNDINGS AND LOWER POPS. UPDATED THE
ZONES AND HWO TO REMOVE THIS MENTION. THE REST OF THE FORECAST IS ON
TRACK WITH THE FOG AND DRIZZLE THROUGH THE NIGHT FOR MUCH OF THE
AREA. UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 820 PM EST TUE DEC 2 2014
00Z SFC ANALYSIS SHOWS A COLD FRONT BISECTING EASTERN KENTUCKY FROM
SOUTHWEST TO NORTHEAST. ALONG THIS BOUNDARY LIGHT RAIN AND PATCHY
DRIZZLE IS AFFECTING MUCH OF FAR EASTERN KENTUCKY. TO THE EAST OF THE
FRONT TEMPERATURES ARE IN THE 50S WHILE 40S ARE FOUND TO THE WEST
ALONG WITH AREAS OF FOG. THIS FOG IS LOCALLY DENSE...PARTICULARLY ON
THE RIDGETOPS. HAVE UPDATED THE FORECAST TO REFLECT THE POPS AND WX
ALONG THE FRONT...BASED ON THE CURRENT TRENDS AND THE LATEST GUIDANCE
FROM THE HRRR AND NAM12. ALSO ADDED FOG TO THE GRIDS TO THE NORTHWEST
OF THE FRONT ALONG WITH SOME DENSE PATCHES ON THE RIDGES. ALSO
TWEAKED HOURLY TEMPS AND DEWPOINTS THROUGH THE NIGHT PER THE LATEST
OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE HAVE BEEN SENT TO THE
NDFD AND WEB SERVERS ALONG WITH AN SPS FOR THE FOG FOR OUR NORTHERN
AND WESTERN HALF OF THE CWA AND AN UPDATED SET OF ZONES AND HWO.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 314 PM EST TUE DEC 2 2014
PRECIPITATION WILL CONTINUE TO WIND DOWN ACROSS EASTERN KENTUCKY
THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING HOURS. BASED
ON CURRENT RADAR TRENDS AND THE LATEST SHORT TERM MODEL DATA...WE
SHOULD SEE A SHORT BREAK IN THE RAIN. THE BREAK WILL BE SHORT
LIVED...HOWEVER...AS ANOTHER WAVE OF LOW PRESSURE IS ALREADY MOVING
OUT OF THE SOUTHERN PLAINS AND ALONG A STALLED OUT FRONTAL BOUNDARY
THAT CURRENTLY STRETCHES DOWN TO THE WESTERN GULF OF MEXICO THEN BACK
NORTHWARD ACROSS THE TEXAS AND OKLAHOMA PAN HANDLE REGIONS. THIS
WAVE IS PROGGED TO BRING PRECIP BACK TO THE AREA BETWEEN 1 AND 3Z
THIS EVENING. IF THE WAVE HOLDS ON ITS FORECAST TRACK...THE BULK OF
RAIN WILL OCCUR IN OUR EASTERN TWO OR THREE TIERS OF COUNTIES
OVERNIGHT. THE SLUGGISH FRONT WILL CONTINUE TO ACT AS A TRIGGER FOR
RAIN SHOWERS THROUGH WEDNESDAY AFTERNOON. THIS SECOND ROUND OF RAIN
SHOULD BE COMING TO END LATE WEDNESDAY. THERE IS A SMALL CHANCE THAT
A FEW RAIN OR SNOW SHOWERS COULD DEVELOP NORTH OF AN APPROACHING WARM
FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...BUT THE MODELS ARE NOT
IN THE BEST AGREEMENT AS TO WHETHER THIS WILL HAPPEN OR NOT. THAT
BEING SAID...DECIDED TO INCLUDE ONLY A SLIGHT CHANCE OF PRECIPITATION
RIGHT AT THE END OF THE SHORT TERM PERIOD. THE TEMPERATURE CURVE FOR
THAT TIME FRAME WOULD ALLOW FOR A MIX OF RAIN AND SNOW SHOULD THERE
BE ENOUGH MOISTURE AND LIFT FOR PRECIPITATION TO FORM. TEMPERATURES
THROUGHOUT THE SHORT TERM PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL FOR TOMORROWS HIGHS AND ABOVE NORMAL TONIGHT FOR THE LOWS.
OVERNIGHT LOWS ON WEDNESDAY LOOK TO BE RIGHT ABOUT NORMAL FOR THE
TIME OF YEAR...WITH SLIGHTLY BELOW NORMAL READINGS POSSIBLE NORTH OF
THE MOUNTAIN PARKWAY...AND RIGHT AT NORMAL SOUTH OF THERE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 PM EST TUE DEC 2 2014
AT UPPER LEVELS... MODELS ARE IN FAIRLY GOOD AGREEMENT OVERALL...
WITH THE 500MB FLOW REMAINING ZONAL THROUGH THE END OF THE WORK
WEEK. THE UPPER LEVEL FLOW PATTERN THEN TRANSITIONS INTO A RIDGE
TROUGH SPLIT OVER THE WESTERN/EASTERN CONUS BY THE FIRST PART OF
NEXT WEEK. THE TRANSITION PERIOD BETWEEN THESE TWO FLOW PATTERNS IS
WHERE MOST OF THE MODEL DIFFERENCES APPEAR TO BE...WITH THE ECMWF
STRENGTHENING AND OR AMPLIFYING THE SOUTHERN STREAM ENERGY AS IT
CROSSES THE CONUS AND THE GFS BEING A BIT MORE PROGRESSIVE.
THOUGH...THE GFS AND CANADIAN MODELS HAVE TRENDED TOWARDS THE ECMWF
SOLUTION TODAY COMPARED TO YESTERDAYS RUNS.
THE UPPER LEVEL FLOW PATTERN TRANSLATES INTO A FAIRLY WET PERIOD AT
THE SFC FOR EASTERN KENTUCKY...WITH THE ONLY EXCEPTION BEING THE
VERY BEGINNING AND END OF THE EXTENDED PERIOD. EARLY THURSDAY MORNING
THERE IS HIGH PRESSURE PROVIDING SOME SUBSIDENCE AND DRYING TO THE
REGION. HOWEVER THIS BREAK FROM PRECIP IS SHORT LIVED AS THE HIGH
QUICKLY PUSHES EWD AND SOUTHERLY LOW-TO-MID LEVEL FLOW USHERS IN
MOISTURE FROM THE GULF. RAIN CHANCES INCREASE AGAIN INTO THE WEEKEND
AS A LOW THAT EJECTED OUT OF THE ROCKIES MAKES ITS WAY INTO OUR
REGION. THE BULK OF THE RAIN FROM THIS SYSTEM WILL LIKELY BE ON
SATURDAY BUT MODELS SHOW SOME LINGERING RAIN SHOWERS THROUGH SUNDAY
AS WELL. FOR THE END OF THE OUTLOOK PERIOD THE REGION WILL GET A
BREAK FROM THE RAIN AS MONDAY/TUESDAY LOOKS TO BE FAIRLY DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 102 AM EST WED DEC 3 2014
SOME SITES HAVE BEEN ABLE TO SEE SOME VFR/MVFR TONIGHT HOWEVER DO
THINK AS NIGHT GOES ON WILL SEE SOME IFR/LIFR AT MANY SITES. MUCH OF
THIS WILL BE DUE TO FOG THAT HAS DEVELOPED AT SEVERAL SITES ALREADY
AND SOME RAIN SHOWERS MOVING ACROSS PORTIONS OF THE CWA TONIGHT.
OTHERWISE DO THINK SITES WILL SLOWLY IMPROVE AS WE MOVE THROUGH THE
TAF PERIOD AS DRIER AIR CONTINUES TO FILTER INTO THE REGION.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...AR
LONG TERM...JVM
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
103 AM EST WED DEC 3 2014
.UPDATE...
ISSUED AT 1105 PM EST TUE DEC 2 2014
DID A QUICK UPDATE TO REFINE THE FORECAST T/TD GRIDS THROUGH THE REST
OF THE NIGHT. DID ALSO LOOK AHEAD TO WEDNESDAY NIGHT AND DECIDED TO
NIX THE IDEA OF SNOW BASED ON SOUNDINGS AND LOWER POPS. UPDATED THE
ZONES AND HWO TO REMOVE THIS MENTION. THE REST OF THE FORECAST IS ON
TRACK WITH THE FOG AND DRIZZLE THROUGH THE NIGHT FOR MUCH OF THE
AREA. UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 820 PM EST TUE DEC 2 2014
00Z SFC ANALYSIS SHOWS A COLD FRONT BISECTING EASTERN KENTUCKY FROM
SOUTHWEST TO NORTHEAST. ALONG THIS BOUNDARY LIGHT RAIN AND PATCHY
DRIZZLE IS AFFECTING MUCH OF FAR EASTERN KENTUCKY. TO THE EAST OF THE
FRONT TEMPERATURES ARE IN THE 50S WHILE 40S ARE FOUND TO THE WEST
ALONG WITH AREAS OF FOG. THIS FOG IS LOCALLY DENSE...PARTICULARLY ON
THE RIDGETOPS. HAVE UPDATED THE FORECAST TO REFLECT THE POPS AND WX
ALONG THE FRONT...BASED ON THE CURRENT TRENDS AND THE LATEST GUIDANCE
FROM THE HRRR AND NAM12. ALSO ADDED FOG TO THE GRIDS TO THE NORTHWEST
OF THE FRONT ALONG WITH SOME DENSE PATCHES ON THE RIDGES. ALSO
TWEAKED HOURLY TEMPS AND DEWPOINTS THROUGH THE NIGHT PER THE LATEST
OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE HAVE BEEN SENT TO THE
NDFD AND WEB SERVERS ALONG WITH AN SPS FOR THE FOG FOR OUR NORTHERN
AND WESTERN HALF OF THE CWA AND AN UPDATED SET OF ZONES AND HWO.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 314 PM EST TUE DEC 2 2014
PRECIPITATION WILL CONTINUE TO WIND DOWN ACROSS EASTERN KENTUCKY
THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING HOURS. BASED
ON CURRENT RADAR TRENDS AND THE LATEST SHORT TERM MODEL DATA...WE
SHOULD SEE A SHORT BREAK IN THE RAIN. THE BREAK WILL BE SHORT
LIVED...HOWEVER...AS ANOTHER WAVE OF LOW PRESSURE IS ALREADY MOVING
OUT OF THE SOUTHERN PLAINS AND ALONG A STALLED OUT FRONTAL BOUNDARY
THAT CURRENTLY STRETCHES DOWN TO THE WESTERN GULF OF MEXICO THEN BACK
NORTHWARD ACROSS THE TEXAS AND OKLAHOMA PAN HANDLE REGIONS. THIS
WAVE IS PROGGED TO BRING PRECIP BACK TO THE AREA BETWEEN 1 AND 3Z
THIS EVENING. IF THE WAVE HOLDS ON ITS FORECAST TRACK...THE BULK OF
RAIN WILL OCCUR IN OUR EASTERN TWO OR THREE TIERS OF COUNTIES
OVERNIGHT. THE SLUGGISH FRONT WILL CONTINUE TO ACT AS A TRIGGER FOR
RAIN SHOWERS THROUGH WEDNESDAY AFTERNOON. THIS SECOND ROUND OF RAIN
SHOULD BE COMING TO END LATE WEDNESDAY. THERE IS A SMALL CHANCE THAT
A FEW RAIN OR SNOW SHOWERS COULD DEVELOP NORTH OF AN APPROACHING WARM
FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...BUT THE MODELS ARE NOT
IN THE BEST AGREEMENT AS TO WHETHER THIS WILL HAPPEN OR NOT. THAT
BEING SAID...DECIDED TO INCLUDE ONLY A SLIGHT CHANCE OF PRECIPITATION
RIGHT AT THE END OF THE SHORT TERM PERIOD. THE TEMPERATURE CURVE FOR
THAT TIME FRAME WOULD ALLOW FOR A MIX OF RAIN AND SNOW SHOULD THERE
BE ENOUGH MOISTURE AND LIFT FOR PRECIPITATION TO FORM. TEMPERATURES
THROUGHOUT THE SHORT TERM PERIOD SHOULD BE AT OR SLIGHTLY BELOW
NORMAL FOR TOMORROWS HIGHS AND ABOVE NORMAL TONIGHT FOR THE LOWS.
OVERNIGHT LOWS ON WEDNESDAY LOOK TO BE RIGHT ABOUT NORMAL FOR THE
TIME OF YEAR...WITH SLIGHTLY BELOW NORMAL READINGS POSSIBLE NORTH OF
THE MOUNTAIN PARKWAY...AND RIGHT AT NORMAL SOUTH OF THERE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 PM EST TUE DEC 2 2014
AT UPPER LEVELS... MODELS ARE IN FAIRLY GOOD AGREEMENT OVERALL...
WITH THE 500MB FLOW REMAINING ZONAL THROUGH THE END OF THE WORK
WEEK. THE UPPER LEVEL FLOW PATTERN THEN TRANSITIONS INTO A RIDGE
TROUGH SPLIT OVER THE WESTERN/EASTERN CONUS BY THE FIRST PART OF
NEXT WEEK. THE TRANSITION PERIOD BETWEEN THESE TWO FLOW PATTERNS IS
WHERE MOST OF THE MODEL DIFFERENCES APPEAR TO BE...WITH THE ECMWF
STRENGTHENING AND OR AMPLIFYING THE SOUTHERN STREAM ENERGY AS IT
CROSSES THE CONUS AND THE GFS BEING A BIT MORE PROGRESSIVE.
THOUGH...THE GFS AND CANADIAN MODELS HAVE TRENDED TOWARDS THE ECMWF
SOLUTION TODAY COMPARED TO YESTERDAYS RUNS.
THE UPPER LEVEL FLOW PATTERN TRANSLATES INTO A FAIRLY WET PERIOD AT
THE SFC FOR EASTERN KENTUCKY...WITH THE ONLY EXCEPTION BEING THE
VERY BEGINNING AND END OF THE EXTENDED PERIOD. EARLY THURSDAY MORNING
THERE IS HIGH PRESSURE PROVIDING SOME SUBSIDENCE AND DRYING TO THE
REGION. HOWEVER THIS BREAK FROM PRECIP IS SHORT LIVED AS THE HIGH
QUICKLY PUSHES EWD AND SOUTHERLY LOW-TO-MID LEVEL FLOW USHERS IN
MOISTURE FROM THE GULF. RAIN CHANCES INCREASE AGAIN INTO THE WEEKEND
AS A LOW THAT EJECTED OUT OF THE ROCKIES MAKES ITS WAY INTO OUR
REGION. THE BULK OF THE RAIN FROM THIS SYSTEM WILL LIKELY BE ON
SATURDAY BUT MODELS SHOW SOME LINGERING RAIN SHOWERS THROUGH SUNDAY
AS WELL. FOR THE END OF THE OUTLOOK PERIOD THE REGION WILL GET A
BREAK FROM THE RAIN AS MONDAY/TUESDAY LOOKS TO BE FAIRLY DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 102 AM EST WED DEC 3 2014
SOME SITES HAVE BEEN ABLE TO SEE SOME VFR/MVFR TONIGHT HOWEVER DO
THINK AS NIGHT GOES ON WILL SEE SOME IFR/LIFR AT MANY SITES. MUCH OF
THIS WILL BE DUE TO FOG THAT HAS DEVELOPED AT SEVERAL SITES ALREADY
AND SOME RAIN SHOWERS MOVING ACROSS PORTIONS OF THE CWA TONIGHT.
OTHERWISE DO THINK SITES WILL SLOWLY IMPROVE AS WE MOVE THROUGH THE
TAF PERIOD AS DRIER AIR CONTINUES TO FILTER INTO THE REGION.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...AR
LONG TERM...JVM
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1151 PM CST Tue Dec 2 2014
.SHORT TERM...(This Afternoon through Thursday night)
Issued at 1152 AM CST TUE DEC 2 2014
Low clouds have persisted and temps are being held down as a
result. The models continue to try and decrease the low trop
moisture through tonight. But, until we see a more clear trend via
satellite, will go slower than any model suggests. We trended more
toward the RAP through the evening hours as it is the most
pessimistic.
High pressure will move across the plains, upper Midwest and
eventually Great Lakes region Wednesday through Wednesday night.
Tonight through Wednesday evening should be dry. We added back
very small chance PoPs to the SW 1/3 of the area after midnight.
Should be a minimal to trace type of event. But, from late
Wednesday night through Thursday morning, both the GFS and ECMWF
show a notable increase in 850-700mb moisture coincident with
increasing QG forcing and isentropic lift/WAA. Ignoring the QPF
forecast as a basis for precip. PoPs will be based on the models
tendency to underestimate light precip chances in this type of
setup, as both the moisture, albeit not terribly deep, is there
along with the forcing. As far as type, could be a mix of very
light rain/sprinkles/light sleet to start. Maybe a very brief
period of light freezing rain/sprinkles/light sleet Thursday
morning over the northern 1/2 of the area. Otherwise just light
rain chances through the day Thursday. Thursday night, rain
chances really ramp up especially after midnight, as mid level
energy pushes east from the central states.
Temps will be a blend of MOS, and base model output.
.LONG TERM...(Friday through Tuesday)
Issued at 300 PM CST TUE DEC 2 2014
The longer term period starts off very wet. All models agree that
shortwave energy over the Plains will move northeast accompanied by
surface low pressure development and an influx of widespread
moisture (with precipitable water values rather high from 1.0 to
1.25 inches). With good isentropic lift associated with the
low-level jet, expect widespread rain during the day Friday and much
of Friday night. Rainfall amounts of over an inch are very possible,
especially along and south/east of the Ohio River. All of the
precipitation will be liquid in the form of rain, but model
soundings Friday night into Saturday morning suggest there could be
some heavier convective showers and perhaps a few rumbles of
thunder, mainly over parts of western KY as the exit region of an
upper jet streak approaches to enhance lift.
How long the rain lingers is unclear at this time, as model runs
show varying strengths and speeds of the system. GFS and ECMWF
maintain an open wave and slightly weaker surface development, while
the GEM is deeper and slower. Overall synoptic pattern favors more
of an open progressive wave, although models at times do suppress
systems a bit too much. For now, will keep system rather
progressive but allow scattered to numerous showers to linger
Saturday before ending later in the day as the system heads east.
Thereafter, the weather should become more benign with no other
significant weather systems expected to approach the region. Thus,
will keep dry weather in the forecast on Sunday and early next week.
Temperatures Friday with the rain will be a bit tricky. Rain should
hold readings down somewhat, especially over southern IL and
southwest IN, but good southerly flow should allow moderation well
up in the 50s over much of western/southwestern KY. High and low
temperatures should remain roughly within several degrees of normal
late in the weekend and early next week.
&&
.AVIATION...
Issued at 1151 PM CST TUE DEC 2 2014
MVFR cigs will persist overnight, improving to low VFR between 15z
and 18z. Vsby should remain VFR, but a few brief dips to MVFR
overnight are not out of the question. Winds will be from the
southwest around 5 kts, gradually shifting to the northwest then
northeast through the day.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AVIATION...RST
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
329 AM EST WED DEC 3 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE
TROUGH AND ASSOCIATED COLD FRONT MOVING ACROSS THE NORTHERN
MISSISSIPPI VALLEY THIS AFTERNOON. AN AREA OF SNOW WITHIN A
MID-LEVEL FGEN BAND OVER NORTHERN WISCONSIN CONTINUES TO
DEVELOP...AND THE LATEST GUIDANCE PUSHES THIS AREA OF SNOW NORTHEAST
ACROSS THE CENTRAL UPPER PENINSULA LATER THIS AFTERNOON. STRONG
GUSTY WINDS OVER WESTERN LAKE SUPERIOR HAVE BEEN GRADUALLY
DIMINISHING WITH THE APPROACH OF THIS COLD FRONT BUT CONTINUE TO
GUST NEAR GALE FORCE OVER THE EASTERN HALF OF THE LAKE. THE MAIN
FORECAST CONCERNS INCLUDE SNOW ACCUMULATIONS FOLLOWED BY GALE
HEADLINES.
TONIGHT...THE SHORTWAVE TROUGH OVER NORTHERN MINNESOTA WILL
CONTINUE TO MOVE EAST AND ACROSS THE REGION. AHEAD OF THE
SHORTWAVE...QG FORCING/MID-LEVEL FGEN WILL COMBINE WITH MID-LEVEL
LAPSE RATES AROUND 6.5 C/KM TO PRODUCE A BAND OF SNOW ACROSS
CENTRAL AND EASTERN SECTIONS OF THE UPPER PENINSULA THIS EVENING.
MODELS PLACE THIS BAND OF SNOW AT DIFFERENT LOCATIONS...BUT
OBSERVATIONAL TRENDS SUPPORT LEANING TOWARDS THE MESO
MODELS...WHICH WOULD CREATE THIS HIGHEST SNOW AMOUNTS FROM IRON
MOUNTAIN TO WHITEFISH POINT. CANNOT RULE OUT SOME ENHANCEMENT OFF
LAKE MICHIGAN DUE TO THE SOUTHERLY WINDS AROUND MANISTIQUE AS
WELL. WILL SHOW A GENERAL 1 TO 2 INCHES IN THESE AREAS...BUT COULD
SEE LOCALLY HIGHER AMOUNTS IN THE LAKE ENHANCEMENT AREAS IF THE
MARGINAL DELTA T/S ARE SUFFICIENT. BEHIND THE SHORTWAVE...WINDS
WILL VEER TO THE WEST OVERNIGHT AND CREATE LAKE EFFECT SNOW
SHOWERS FROM ONTONAGON TO THE TIP OF THE KEWEENAW. SUBSIDENCE
BEHIND THE SHORTWAVE WILL LIMIT ACCUMS TO SUB ADVISORY LEVELS.
LOWS RANGING FROM THE MIDDLE SINGLE DIGITS SOUTH-CENTRAL TO THE
MIDDLE TEENS NEAR THE GREAT LAKES.
WEDNESDAY...AS THE SHORTWAVE EXITS THE REGION DURING THE
MORNING...VEERING WINDS TO THE WNW WILL BE COLD AND DRY AIR
ADVECTING OVER THE COURSE OF THE DAY. HIGH TEMPERATURES WILL BE A
FEW DEGREES COLDER AS A RESULT. DELTA T/S WILL BECOME MORE
FAVORABLE FOR LAKE EFFECT SNOW IN THE WESTERLY SNOW BELTS...BUT
THAT WILL BE COUNTERACTED BY THE INCOMING DRY AIRMASS.
REGARDLESS...SNOW INTENSITY SHOULD INCREASE FROM GRAND MARAIS
THROUGH WHITEFISH POINT IN THE AFTERNOON AS WIND DIRECTIONS VEER.
COULD SEE ANOTHER INCH OR TWO IN THE SNOW BELTS. HIGHS RANGING
FROM THE UPPER TEENS SOUTHWEST TO THE MIDDLE 20S EAST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 329 AM EST WED DEC 3 2014
NAM SHOWS A BROAD 500 MB TROUGH OVER MOST OF CANADA WITH THE TROUGH
AXIS OVER EASTERN CANADA 12Z THU. AN UPPER RIDGE STARTS TO BUILD
INTO THE WESTERN U.S. 12Z FRI AND IS QUICKLY REPLACED BY A TROUGH
FOR 12Z SAT.
IT LOOKS BORDERLINE FOR LAKE ENHANCEMENT SNOW AS 850 MB TEMPERATURES
ARE AROUND -6C AND LAKE SUPERIOR AND LAKE MICHIGAN TEMPERATURES ARE
AROUND 4C TO 5C. LOOKED LIKE THERE COULD BE SOME LAKE MICHIGAN
ENHANCEMENT ON FRIDAY OVER THE EAST AND PUT SOME SLIGHT CHANCE POPS
IN. OTHERWISE...LAKE EFFECT PCPN STAYS OFFSHORE AND AWAY FROM THE
AREA. OTHERWISE...DID NOT MAKE TOO MANY CHANGES TO THE FORECAST AND
TEMPERATURES STAY NEAR NORMAL THIS FORECAST PERIOD.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH OVER CENTRAL
CANADA WITH A BROAD TROUGH OVER THE UPPER GREAT LAKES 12Z SAT WITH
SFC HIGH PRESSURE OVERHEAD. THE SFC HIGH MOVES OFF TO THE EAST 12Z
SUN INTO EASTERN CANADA WITH TROUGHING MOVING INTO THE NORTHERN
PLAINS. THE TROUGH MOVES INTO THE UPPER GREAT LAKES 12Z MON AND THIS
TROUGH MOVES INTO THE LOWER GREAT LAKES 12Z TUE WITH SFC HIGH
PRESSURE AGAIN OVERHEAD. FRONTAL SYSTEM MOVES THROUGH THE AREA ON
MON. WILL BE DRY ON SATURDAY AND SAT NIGHT AND THEN HAVE SOME POPS
IN FOR SUN THROUGH MON WITH SYSTEM MOVING THROUGH. TEMPERATURES LOOK
TO BE NEAR NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1158 PM EST TUE DEC 2 2014
UNDER WESTERLY WINDS...LAKE EFFECT SNOW SHOWERS/MVFR CONDITIONS ARE
EXPECTED AT KCMX OVERNIGHT. HOWEVER...AS THE NIGHT WEARS ON...THERE
WILL BE A GREATER POTENTIAL FOR IFR VIS. AT KIWD...INITIAL VFR
CONDITIONS SHOULD BECOME MVFR LATER IN THE NIGHT AS LAKE EFFECT
CLOUDS DEVELOP. MEANWHILE AT KSAW...THERE MAY BE SOME FLUCTUATION
BTWN VFR AND MVFR OVERNIGHT AS OBS/SATELITTE IMAGERY SHOW MVFR CIGS
TO THE W. TODAY...COLDER AIR WILL FLOW INTO THE AREA ON
STRENGTHENING WNW WINDS BEHIND A TROF. AT THE MORE EXPOSED KCMX
TERMINAL...WINDS WILL GUST AOA 30KT. COMBINATION OF -SHSN/BLSN WILL
LIKELY LEAD TO PREVAILING LIFR CONDITIONS FROM MID MORNING THRU
EARLY AFTN AT KCMX. SLOW IMPROVEMENT TO IFR THEN MVFR IS EXPECTED IN
THE AFTN/EVENING AS WINDS GRADUALLY DIMINISH AND DRIER AIR ARRIVES.
AT KIWD...EXPECT MVFR CONDITIONS TO PREVAIL TODAY UNDER LAKE EFFECT
CLOUDS/OCNL -SHSN. AT KSAW...ALTHOUGH DOWNSLOPING WNW WINDS SHOULD
FAVOR VFR CONDITIONS...MODELS ARE SUGGESTING MVFR CIGS FROM LATE
MORNING UNTIL LATE AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
SOUTHERLY GALES ARE ONGOING ACROSS THE EASTERN HALF OF THE LAKE.
SHOULD SEE WINDS DIMINISH AS A COLD FRONT APPROACHES THE
REGION BY EARLY THIS EVENING. BEHIND THE FRONT...ANOTHER W-NW GALE EVENT
WILL FOLLOW WEDNESDAY AFTERNOON AND NIGHT. BUT SINCE THE WEATHER
PATTERN IS PROGRESSIVE...THE PASSAGE OF THE TRAILING HI PRES RIDGE
THRU THE AREA ON THU WILL RESULT IN DIMINISHING/BACKING WINDS TO
THE SW FOR LATER IN THE WEEK. NO GALES ARE EXPECTED DURING THIS
TIME.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 10 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR
LSZ248>251-265>267.
GALE WARNING FROM 10 AM THIS MORNING TO 9 PM EST THIS EVENING
FOR LSZ244-245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...MPC
LONG TERM...07
AVIATION...ROLFSON
MARINE...MPC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1159 PM EST TUE DEC 2 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE
TROUGH AND ASSOCIATED COLD FRONT MOVING ACROSS THE NORTHERN
MISSISSIPPI VALLEY THIS AFTERNOON. AN AREA OF SNOW WITHIN A
MID-LEVEL FGEN BAND OVER NORTHERN WISCONSIN CONTINUES TO
DEVELOP...AND THE LATEST GUIDANCE PUSHES THIS AREA OF SNOW NORTHEAST
ACROSS THE CENTRAL UPPER PENINSULA LATER THIS AFTERNOON. STRONG
GUSTY WINDS OVER WESTERN LAKE SUPERIOR HAVE BEEN GRADUALLY
DIMINISHING WITH THE APPROACH OF THIS COLD FRONT BUT CONTINUE TO
GUST NEAR GALE FORCE OVER THE EASTERN HALF OF THE LAKE. THE MAIN
FORECAST CONCERNS INCLUDE SNOW ACCUMULATIONS FOLLOWED BY GALE
HEADLINES.
TONIGHT...THE SHORTWAVE TROUGH OVER NORTHERN MINNESOTA WILL
CONTINUE TO MOVE EAST AND ACROSS THE REGION. AHEAD OF THE
SHORTWAVE...QG FORCING/MID-LEVEL FGEN WILL COMBINE WITH MID-LEVEL
LAPSE RATES AROUND 6.5 C/KM TO PRODUCE A BAND OF SNOW ACROSS
CENTRAL AND EASTERN SECTIONS OF THE UPPER PENINSULA THIS EVENING.
MODELS PLACE THIS BAND OF SNOW AT DIFFERENT LOCATIONS...BUT
OBSERVATIONAL TRENDS SUPPORT LEANING TOWARDS THE MESO
MODELS...WHICH WOULD CREATE THIS HIGHEST SNOW AMOUNTS FROM IRON
MOUNTAIN TO WHITEFISH POINT. CANNOT RULE OUT SOME ENHANCEMENT OFF
LAKE MICHIGAN DUE TO THE SOUTHERLY WINDS AROUND MANISTIQUE AS
WELL. WILL SHOW A GENERAL 1 TO 2 INCHES IN THESE AREAS...BUT COULD
SEE LOCALLY HIGHER AMOUNTS IN THE LAKE ENHANCEMENT AREAS IF THE
MARGINAL DELTA T/S ARE SUFFICIENT. BEHIND THE SHORTWAVE...WINDS
WILL VEER TO THE WEST OVERNIGHT AND CREATE LAKE EFFECT SNOW
SHOWERS FROM ONTONAGON TO THE TIP OF THE KEWEENAW. SUBSIDENCE
BEHIND THE SHORTWAVE WILL LIMIT ACCUMS TO SUB ADVISORY LEVELS.
LOWS RANGING FROM THE MIDDLE SINGLE DIGITS SOUTH-CENTRAL TO THE
MIDDLE TEENS NEAR THE GREAT LAKES.
WEDNESDAY...AS THE SHORTWAVE EXITS THE REGION DURING THE
MORNING...VEERING WINDS TO THE WNW WILL BE COLD AND DRY AIR
ADVECTING OVER THE COURSE OF THE DAY. HIGH TEMPERATURES WILL BE A
FEW DEGREES COLDER AS A RESULT. DELTA T/S WILL BECOME MORE
FAVORABLE FOR LAKE EFFECT SNOW IN THE WESTERLY SNOW BELTS...BUT
THAT WILL BE COUNTERACTED BY THE INCOMING DRY AIRMASS.
REGARDLESS...SNOW INTENSITY SHOULD INCREASE FROM GRAND MARAIS
THROUGH WHITEFISH POINT IN THE AFTERNOON AS WIND DIRECTIONS VEER.
COULD SEE ANOTHER INCH OR TWO IN THE SNOW BELTS. HIGHS RANGING
FROM THE UPPER TEENS SOUTHWEST TO THE MIDDLE 20S EAST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
A RELATIVELY FLAT ZONAL FLOW ACROSS THE CONUS WL KEEP ARCTIC AIR
LOCKED NORTH IN CANADA AND LIMIT SNOW POTENTIAL OVER UPR MI THRU
SAT. A QUICK MOVING SHORTWAVE TROF IS FCST TO REACH THE GREAT
LAKES REGION SUNDAY NGT/MON AND BRING THE NEXT CHC OF SYNOPTIC
SNOW...LAKE EFFECT SNOW SHWRS TO THE AREA. TOO EARLY YET FOR
SPECIFICS AS THE MDLS HAVE DIFFERENCES ON THE SPEED AND DEPTH OF
THE SHORTWAVE TRFO AS WELL AS THE AMOUNT OF WARM AIR THAT MAY GET
DRAWN NORTH AHEAD OF THE SYSTEM WHICH MAY LIMIT ACCUMULATIONS.
TEMPS WL LIKELY END UP CLOSE TO NORMAL WITH BRIEF WARM-UPS
FOLLOWED BY BRIEF COOL DOWNS.
W-NW WINDS TO CONT INTO WED EVENING...BRINGING LAKE EFFECT SNOW
SHWRS TO MUCH OF THE NRN SECTION OF UPR MI. KEWEENAW...HOUGHTON...
ALGER AND LUCE COUNTIES TO BE THE MOST SUSCEPTIBLE TO ACCUMULATING
SNOW...ESPECIALLY THE LATTER 2 COUNTIES WHO HAVE THE LONGEST
FETCH. ADDITIONAL ACCUMULATIONS TO RANGE FROM AN INCH OR LESS NW
SECTIONS OF THE FORECAST AREA...TO 1 TO 3 INCHES FOR ERN SECTIONS.
THE LAKE EFFECT WL TEND TO WEAKEN OVER THE WRN U.P. LATER WED NGT
AS WINDS BEGIN TO BACK TO THE W-SW DUE TO THE PASSAGE OF A SURFACE
RIDGE OF HI PRES. BEFORE THE SURFACE RIDGE ARRIVES...IT COULD BE A
GUSTY EVENING OVER THE REGION WITH WIND GUSTS APPROACHING 30 MPH
ALONG THE LAKE SUPERIOR SHORELINE. THIS WL GENERATE BLOWING/DRIFTING
OF THE NEW SNOW. QUITE A RANGE IN TEMPS EXPECTED WED NGT BETWEEN THE
DECREASING CLODUS/DIMINISHING WINDS OVER WRN SECTIONS AND MORE
CLOUDS/WIND OVER ERN SECTIONS. LOOK FOR READINGS TO RANGE FROM A
COUPLE OF DEGS EITHER SIDE OF ZERO INTERIOR WEST TO THE MID-TEENS
FROM GRAND MARAIS EWD.
AS THE HIGH PRESSURE SLIDES TO THE EAST ON THU...RETURN FLOW
DEVELOPS ACROSS UPR MI AS WINDS BACK TO THE S-SW. PRETTY STRONG
SURGE OF WAA INDICATED BY THE MODELS AS 8H TEMPS CLIMB FROM THE
TEENS BELOW ZERO TO THE SINGLE DIGITS BELOW ZERO(C). THE
ISENTROPIC LIFT IS NOT STRONG ENUF TO ALLOW PCPN TO DEVELOP...
HOWEVER THERE IS ENUF LIFT TO BRING MORE CLOUDS BACK INTO THE
PICTURE...ESPECIALLY DURING THE AFTERNOON. THE COMBINATION OF A
COLD START TO THE DAY AND INCREASING CLOUDS WL COUNTER THE WARMING
TEMPS ALOFT...THUS MAX TEMPS TO ONLY REACH THE LOWER TO MID 20S.
QUIET CONDITIONS EXPECTED THU NGT AS THE S-SW WINDS TO PERSIST AND
LITTLE EVIDENCE OF ANY LIFTING MECHANISM ADVERTISED BY THE MODELS.
STILL A DECENT AMOUNT OF CLOUDS ANTICIPATED AND THIS WL HELP HOLD
TEMPS UP A BIT. LOOK FOR MIN TEMPS TO SETTLE MAINLY INTO THE TEENS.
A WEAK COLD FRONT IS FCST TO MOVE INTO THE REGION FRI AFTERNOON AND
VEER THE WINDS MORE TO THE W-NW BY 00Z SAT. LITTLE IN THE WAY OF
MOISTURE IS APPARENT AS A SRN STREAM SYSTEM OVER THE OZARKS/TN
VALLEY INTERCEPTS ANY GULF MOISTURE. PREFER TO LEAVE THE FCST DRY
PER PREVIOUS SHIFT. MAX TEMPS TO MAINLY BE IN THE 30-35 DEG RANGE
WITH THE WARMER READINGS IN THE EAST.
A LARGE CANADIAN HI PRES TO BE OUR MAIN WEATHER FEATURE FOR THE
FIRST HALF OF THE UPCOMING WEEKEND AND PROVIDE A MOSTLY DRY
STRETCH OF WEATHER. THE ONLY EXCEPTION WOULD BE A MINIMAL CHC OF
LAKE EFFECT SNOW SHWRS NEAR LAKE SUPERIOR DUE TO N-NW WINDS. 8H
TEMPS ONLY AROUND -8C OVER THE LAKE WOULD LIMIT SNOW POTENTIAL.
TRAJS BECOME UNFAVORABLE BY SAT...SO DRY CONDITIONS TO PREVAIL.
MAX TEMPS ON SAT TO AGAIN BE GENERALLY IN THE 30-35 DEG RANGE WITH
A FEW UPR 20S OVER THE INTERIOR WEST.
AFTER A QUIET SAT NGT...ATTENTION TURNS TO THE WEST WHERE A WEAK
SFC LOW/CDFNT AND SHORTWAVE TROF ARE PROGGED TO MOVE EAST INTO THE
UPR MS VALLEY/WRN GREAT LAKES ON SUNDAY. 12Z GFS/GEM ARE SLOWER
WITH THE MOVEMENT OF THIS SYSTEM AND BARELY GET THE LEADING EDGE
OF PCPN TO FAR WRN SECTIONS BY 00Z MON. MEANWHILE...THE ECMWF/UKMET
ARE FASTER OVERALL AND WOULD BRING THE PCPN CHCS THRU ALMOST ALL
OF UPR MI BY 00Z MON. DUE TO THE WIDE DISCREPANCY IN TIMING...HAVE
FOLLOWED THE CONSENSUS SOLUTION FOR NOW WHICH BRINGS PCPN CHCS THRU
MOST OF UPR MI SUNDAY AFTERNOON. ANOTHER POTENTIAL CONCERN IS PCPN
TYPE...ESPECIALLY IF THE GFS/GEM ARE CORRECT WHERE A MIX WOULD BE
POSSIBLE HEADED INTO SUNDAY EVENING.
THE CHCS FOR BOTH SYNOPTIC AND LAKE EFFECT SNOWS WL CONT INTO
SUNDAY NGT AS THE SYSTEM PUSHES ACROSS THE GREAT LAKES. MUCH TOO
EARLY FOR ANY ACCUMULATION NUMBERS...ESPECIALLY DUE TO THE
DIFFERENCES IN THE MODELS. LAKE EFFECT SNOW SHWRS BECOME MORE OF
AN ISSUE HEADED INTO MON AS WINDS EVENTUALLY BECOME NW AND CAA
SWEEPS SWD SENDING 8H TEMPS DOWN INTO THE -10 TO -15 DEG RANGE(C).
HAVE PLACED HIGHER CHC POPS OVER THE TYPICALLY FAVORED LOCATIONS
FROM KEWEENAW EWD. THE LAKE EFFECT POTENTIAL IS EXPECTED TO LINGER
INTO MON NGT BEFORE GRADUALLY TAPERING OFF HEADED INTO TUE AS
ANOTHER AREA OF HI PRES BUILDS INTO THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1158 PM EST TUE DEC 2 2014
UNDER WESTERLY WINDS...LAKE EFFECT SNOW SHOWERS/MVFR CONDITIONS ARE
EXPECTED AT KCMX OVERNIGHT. HOWEVER...AS THE NIGHT WEARS ON...THERE
WILL BE A GREATER POTENTIAL FOR IFR VIS. AT KIWD...INITIAL VFR
CONDITIONS SHOULD BECOME MVFR LATER IN THE NIGHT AS LAKE EFFECT
CLOUDS DEVELOP. MEANWHILE AT KSAW...THERE MAY BE SOME FLUCTUATION
BTWN VFR AND MVFR OVERNIGHT AS OBS/SATELITTE IMAGERY SHOW MVFR CIGS
TO THE W. TODAY...COLDER AIR WILL FLOW INTO THE AREA ON
STRENGTHENING WNW WINDS BEHIND A TROF. AT THE MORE EXPOSED KCMX
TERMINAL...WINDS WILL GUST AOA 30KT. COMBINATION OF -SHSN/BLSN WILL
LIKELY LEAD TO PREVAILING LIFR CONDITIONS FROM MID MORNING THRU
EARLY AFTN AT KCMX. SLOW IMPROVEMENT TO IFR THEN MVFR IS EXPECTED IN
THE AFTN/EVENING AS WINDS GRADUALLY DIMINISH AND DRIER AIR ARRIVES.
AT KIWD...EXPECT MVFR CONDITIONS TO PREVAIL TODAY UNDER LAKE EFFECT
CLOUDS/OCNL -SHSN. AT KSAW...ALTHOUGH DOWNSLOPING WNW WINDS SHOULD
FAVOR VFR CONDITIONS...MODELS ARE SUGGESTING MVFR CIGS FROM LATE
MORNING UNTIL LATE AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED BY NATIONAL WEATHER SERVICE GREEN BAY WI AT
415 PM EST TUE DEC 2 2014
SOUTHERLY GALES ARE ONGOING ACROSS THE EASTERN HALF OF THE LAKE.
SHOULD SEE WINDS DIMINISH AS A COLD FRONT APPROACHES THE
REGION BY EARLY THIS EVENING. BEHIND THE FRONT...ANOTHER W-NW GALE EVENT
WILL FOLLOW WEDNESDAY AFTERNOON AND NIGHT. BUT SINCE THE WEATHER
PATTERN IS PROGRESSIVE...THE PASSAGE OF THE TRAILING HI PRES RIDGE
THRU THE AREA ON THU WILL RESULT IN DIMINISHING/BACKING WINDS TO
THE SW FOR LATER IN THE WEEK. NO GALES ARE EXPECTED DURING THIS
TIME.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 10 AM WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR LSZ248>251-265>267.
GALE WARNING FROM 10 AM TO 9 PM EST WEDNESDAY FOR LSZ244-245-263-
264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...MPC
LONG TERM...AK
AVIATION...ROLFSON
MARINE...MPC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1149 PM EST TUE DEC 2 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 312 PM EST TUE DEC 2 2014
LOW PRESSURE TRACKING NORTH OF THE GREAT LAKES WILL BRING SOME
LIGHT SNOW TONIGHT WITH LITTLE OR NO ACCUMULATION. GENERALLY FAIR
WEATHER WILL FOLLOW FOR THIS WEEK.
&&
.UPDATE...
ISSUED AT 831 PM EST TUE DEC 2 2014
WE HAVE UPDATED THE FCST THIS EVENING TO BUMP UP THE SNOW CHCS...
ESPECIALLY UP ACROSS THE NW PORTION OF THE CWFA. RADAR SHOWS THE
LIGHT SNOW IS ON SCHEDULE AS MID AND UPPER LEVEL MOISTURE UP NORTH
AHEAD OF THE SHORT WAVE IS STARTING TO OVERLAP WITH LOW LEVEL
MOISTURE ADVECTING IN FROM THE SOUTH. THE BEST OVERLAP OCCURS
ACROSS THE NW PORTION OF THE CWFA...ALONG WITH SOME ADDED MOISTURE
OCCURRING UP THERE DUE TO A CONTRIBUTION FROM THE LAKE. DELTA T/S
ARE RELATIVELY SMALL...SO NOT MUCH TEXTBOOK LAKE ENHANCEMENT GOING ON.
THE MID AND UPPER LEVEL MOISTURE WILL MOVE OUT OF THE AREA QUICKLY
DURING THE LATE EVENING AND EARLY OVERNIGHT HOURS.
WE ARE STILL EXPECTING A CHC OF SOME PATCHY FREEZING DRIZZLE DOWN
SOUTH...FURTHER REMOVED FROM THE DEEPER MOISTURE ALLOWING FOR AN
UNSATURATED DGZ. THIS IS NOT EXPECTED TO BE SIGNIFICANT OR LONG
DURATION IN NATURE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 312 PM EST TUE DEC 2 2014
PRETTY QUIET WEATHER TONIGHT THROUGH THURSDAY NIGHT WITH THE ONLY
CHANCE FOR ANY MEASURABLE PRECIP BEING TONIGHT...WHICH SHOULD NOT
AMOUNT TO MUCH. RADAR CURRENTLY SHOWING AREA OF LIGHT SNOW ACROSS
WESTERN WISCONSIN IN AN AREA OF ISENTROPIC ASCENT AND THIS WILL
MOVE EAST TONIGHT WITH LIGHT SNOW PROGGED TO ARRIVE AROUND 01Z
ACROSS THE WESTERN ZONES PER THE HRRR. EXPECT ANY ACCUMS TO BE AN
INCH OR LESS WITH THE BEST CHANCE ACROSS THE NORTHERN FORECAST
AREA.
THE DGZ DRIES OUT BETWEEN 06Z AND 12Z AND THERE REMAINS SOME LIFT
IN THE SHALLOW STRATUS DURING AND AFTER THAT TIME...SO SOME PATCHY
FREEZING DRIZZLE IS POSSIBLE...BUT AGAIN THIS SHOULD BE FAIRLY
LIGHT AND IS NOT EXPECTED TO CAUSE ANY MAJOR IMPACTS.
SOME LIGHT LAKE EFFECT SNOW SHOWERS ARE POSSIBLE ACROSS THE
NORTHWEST FORECAST AREA EARLY WEDNESDAY BEFORE SFC HIGH BUILDS IN
AND INVERSION HEIGHTS CRASH. THIS SFC HIGH WILL BRING FAIR WEATHER
THROUGH THE REST OF THE NEAR TERM.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 312 PM EST TUE DEC 2 2014
MEDIUM RANGE MODELS CONTINUE TO SHOW A SOUTHERN STREAM SYSTEM
PULLING ACROSS THE TN VALLEY FRIDAY NIGHT AND SATURDAY. WE SHOULD
REMAIN ON THE NORTHERN EDGE OF THIS STORM. SOME LIGHT RAIN...
POSSIBLY MIXED WITH SNOW...MAY OCCUR NEAR I-94 OTHERWISE IT APPEARS
THE REST OF THE CWA REMAINS DRY.
AFTER A FAIRLY QUIET PERIOD A NORTHERN STREAM SYSTEM TAKES SHAPE
OVER THE NORTHERN PLAINS BY THE END OF THE WEEKEND. THIS SHOULD
BRIEFLY BRING TEMPS ABOVE NORMAL SATURDAY NIGHT THROUGH SUNDAY NIGHT
AS SOUTHERLY WINDS PUSH IN AHEAD OF THE DEVELOPING SYSTEM. THE
STORM AGGRESSIVELY GETS WOUND UP AND SHOULD GIVE US WINDY CONDITIONS
BY MONDAY...AND THEN TRANSFERS ENERGY INTO A NOREASTER INTO MONDAY
NIGHT. HOWEVER THE BEST MOISTURE AND DYNAMICS REMAINS TO OUR NORTH
AND EAST...SO PCPN OVER SW MI LOOKS FAIRLY MINIMAL. COOLER TEMPS
AND SOME LIGHT LAKE EFFECT SNOW LOOKS POSSIBLE BEHIND THE SYSTEM
LATER MONDAY AND CARRYING INTO TUESDAY WITH H8 TEMPS DROPPING TO
AROUND -6C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1149 PM EST TUE DEC 2 2014
IFR CONDITIONS HAVE OVERSPREAD MOST OF THE TAF SITES AS WAS
SUGGESTED BY THE 00Z TAF DISCUSSION. ALSO THAT BAND OF SNOW OVER
WI HAS INDEED MOVED INTO THE MKG AND GRR TAF SITES. THE HRRR IS
DOING VERY NICELY WITH THIS SNOW BAND IN SHOWS THE SECOND BAND
REDEVELOPING SOUTH OF THE CURRENT BAND THAN THEN MOVES EAST ACROSS
THE I-96 TAF SITES BETWEEN 06Z AND 09Z. SINCE THE HRRR HAS DONE SO
WELL WITH THIS THIS EVENING I WENT WITH THIS IDEA.
THE FREEZING DRIZZLE OVER GRR SHOULD CHANGE TO ALL SNOW ONCE THAT
SECOND BAND DEVELOPS OVER THE AREA AROUND 06Z. SO I TOOK THE
FREEZING DRIZZLE OUT OF THE GRR TAF AT THAT POINT. I DID NO ADD IT
TO THE 8I-94 TAF SITES BUT THEY MAY WELL HAVE A SIMILAR PROBLEM AS
GRR DOES NOW IN THAT THE DEEP MOISTURE DOES NOT GET OVERHEAD
THERE.
ALL OF THIS MOVES OUT RATHER DRAMATICALLY BETWEEN 12Z AND 15Z AS
DRY AIR SURGES IN AND AS WE SAW YESTERDAY... THE SKY CAN AND WILL
CLEAR OF LOW CLOUDS IF THE AIR BECOMES DRY ENOUGH... WHICH IT
SHOULD SO ALL TAF SITES SHOULD BE VFR BY 16Z WEDNESDAY.
&&
.MARINE...
ISSUED AT 257 PM EST TUE DEC 2 2014
WINDS AND WAVES WILL CONTINUE HAZARDOUS TO SMALL CRAFT UNTIL
THURSDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 257 PM EST TUE DEC 2 2014
NO HYDRO ISSUES EXPECTED THIS WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST THURSDAY FOR LMZ844>849.
&&
$$
UPDATE...NJJ
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...OSTUNO/JK
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
344 AM CST WED DEC 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 327 AM CST WED DEC 3 2014
A WEAK AREA OF ARCTIC HIGH PRESSURE ACROSS ERN
MT WILL BUILD SOUTHEAST AND FUSE WITH THE MODIFIED ARCTIC HIGH
ACROSS WRN NEB THIS MORNING. THE RESULT IS A DRY 1030MB HIGH WHICH
THEN MOVES EAST TODAY AND TONIGHT SETTING UP A RETURN FLOW. BY 12Z
THURSDAY WARM AIR HAS RETURNED TO THE FCST AREA WITH SFC LOW
PRESSURE OVER SCNTL SD. DEWPOINTS HAVE ALREADY BEEN ADJUSTED DOWN
TOWARD THE VERY DRY RAP MODEL WHICH PRODUCES DEWPOINTS IN THE SINGLE
DIGITS TODAY. THE TEMPERATURE FORECAST IS BASED SOLELY ON BIAS
CORRECTED MET...MAV AND ECS GUIDANCE FOR HIGHS CLOSE TO WHAT THE RAP
INDICATES...UPPER 30S TO LOWER 40S. A BATCH OF MID AND HIGH LEVEL
CLOUDS ACROSS THE COLORADO LIFTS EAST NORTHEAST TODAY. THE MODEL
CONSENSUS SUGGESTS THE DENSER MID LEVEL CLOUDS WOULD MOVE MOSTLY
ACROSS NWRN NEB THIS AFTN WITH SKIES CLEARING EARLY THURSDAY MORNING.
A SIMILAR STRATEGY IS IN PLACE TONIGHT FOR BIAS CORRECTED LOWS IN
THE TEENS AND 20S. THE STRONG RETURN FLOW SPENDS THE NIGHT WORKING
ITS WAY ACROSS THE FCST AREA LIMITING RADIATIONAL COOLING TO THE FEW
HOURS TOWARD MORNING WHEREBY WINDS WOULD DECOUPLE ACROSS SRN NEB BUT
REMAIN STRONG IN THE NORTHEAST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 327 AM CST WED DEC 3 2014
DRY WEATHER WILL CONTINUE THROUGH THE PERIOD ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA. A WESTERLY DOWNSLOPE CHINOOK WIND WILL
ADVECT 8 TO 10C H850 MB TEMPERATURES EASTWARD ACROSS THE AREA
THURSDAY. AS THIS AIR IS MIXED TO THE SURFACE...HIGHS SHOULD BE
WELL INTO THE 50S ACROSS WESTERN NEBRASKA...WITH 45 TO 52F FOR
AREAS FARTHER EAST. DESPITE THE WARMER AIR...FIRE WEATHER
CONDITIONS WILL REMAIN IN CHECK...AS SOME PACIFIC MOISTURE ACTUALLY
MAKES IT EAST OVER THE ROCKIES WITH DEW POINTS IN THE MID 20S TO
AROUND 30 DEGREES.
FOR FRIDAY AND THE WEEKEND...A COUPLE OF WEAK SYSTEMS WILL MOVE
ACROSS SOUTHERN CANADA. THIS WILL DRIVE A WEAK COLD FRONT SOUTH
INTO THE AREA FRIDAY. THE FRONT WILL LIFT BACK NORTH INTO THE
NORTHERN PLAINS AS A WARM FRONT SATURDAY AND SUNDAY...WITH A MILD
WEEKEND EXPECTED FOR OUR AREA. A STRONGER ALBERTA CLIPPER WILL
DIVE SOUTHEAST SUNDAY NIGHT INTO MONDAY ACROSS NORTH DAKOTA INTO
NORTHERN MINNESOTA. THIS COULD SEND A SHOT OF ARCTIC AIR INTO
NORTH CENTRAL THROUGH EASTERN NEBRASKA MONDAY. THIS WILL BE BRIEF
HOWEVER...WITH A RAPID RETURN OF SOUTHERLY WINDS AND WARMING
TEMPERATURES TUESDAY INTO WEDNESDAY AS ANOTHER PLUM OF WARM AIR
ALOFT MOVES EAST OFF THE HIGHER TERRAIN TO THE WEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1128 PM CST TUE DEC 2 2014
ABUNDANT MID AND HIGH LEVEL MOISTURE WILL PUSH INTO THE CENTRAL
AND SOUTHERN ROCKIES OVERNIGHT. THIS MOISTURE WILL TRANSITION EAST
ONTO THE CENTRAL AND SOUTHERN PLAINS TOWARD MORNING...RESULTING IN
INCREASING HIGH LEVEL CLOUDINESS. LOOK FOR SKIES TO TRANSITION
FROM SCATTERED TO BROKEN CIGS AON 25000 FT AGL FROM WEDNESDAY
MORNING THROUGH WEDNESDAY AFTERNOON. ON WEDNESDAY EVENING...A WARM
FRONT WILL LIFT EAST ACROSS THE PANHANDLE AND WESTERN NEBRASKA. AS
THIS FEATURE PASSES...INCREASED MID LEVEL CLOUDINESS IS EXPECTED
WEDNESDAY EVENING WITH CIGS AROUND 10000 FT AGL. WINDS WILL BE
VARIABLE AT UNDER 10 KTS OVERNIGHT THROUGH WEDNESDAY
MORNING...SHIFTING TO THE SOUTH AT 10 TO 15 KTS WEDNESDAY
AFTERNOON AND EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1235 AM EST WED DEC 3 2014
.SYNOPSIS...
A COLD FRONT STALLED SOUTH OF THE AREA WILL LIFT NORTH ON WEDNESDAY.
ANOTHER COLD FRONT WILL PUSH SOUTH ACROSS THE AREA THURSDAY MORNING
WITH HIGH PRESSURE BUILDING IN FROM THE NORTH BEHIND THE FRONT. A
WEAK SURFACE LOW WILL DRAG A COLD FRONT ACROSS THE AREA THIS
WEEKEND...INCREASING RAIN CHANCES SATURDAY AND SUNDAY. HIGH PRESSURE
RETURNS TO THE AREA SUNDAY THROUGH TUESDAY.SEASONABLE CONDITIONS ARE
EXPECTED FOR THE BEGINNING OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM WEDNESDAY...FOG IS BECOMING WIDESPREAD ALONG THE COAST
AND I ANTICIPATE I WILL NEED TO ISSUE A DENSE FOG ADVISORY SOMETIME
IN THE NEXT FEW HOURS. RAISED FORECAST LOWS BY SEVERAL DEGREES AS
DENSE LOW CLOUDS AND WEAKENING WINDS WILL NEITHER ALLOW RADIATIONAL
COOLING OR ADVECTION OF COOLER AIR IN FROM THE NORTH. PREVIOUS
DISCUSSION FROM 930 PM FOLLOWS...
COLD FRONT DRAPED ACROSS SOUTH CAROLINA SOUTH OF LOCAL FORECAST AREA
WITH LIGHT COOL NORTHEAST FLOW AT THE SFC ACROSS THE AREA THIS
EVENING AS WEDGE OF HIGH PRESSURE EXTENDS DOWN FROM HIGH PRESSURE
OVER THE NORTHEAST. STRONG LOW LEVEL INVERSION AS WARM MOIST
SOUTHERLY FLOW EXISTS JUST ABOVE THE SURFACE. THIS WILL HELP TO LOCK
IN MOISTURE WITH LOW STRATUS AND FOG INCREASING ACROSS THE AREA AS
NE SFC WINDS DIMINISH AND SHIFT EAST. MODELS SHOWING SHWRS AND BEST
LIFT SHIFTING NORTH THROUGH TONIGHT AS HIGH PRESSURE WELL NORTH OF
THE AREA OVER THE CANADIAN MARITIMES SHIFTS EAST...BUT MOIST ON
SHORE FLOW WILL HELP TO KEEP MOISTURE FLOWING IN OVERNIGHT WITH LOW
CLOUDS AND DRIZZLE POSSIBLE. SOME AREAS MAY SEE DENSE FOG
DEVELOPING. LOWS WILL RANGE FROM THE UPPER 40S MOST PLACES TO THE
LOWER 50S OVER NORTHEAST SOUTH CAROLINA COAST.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 215 PM TUESDAY...SURFACE HIGH SHIFTING OFF THE COAST WED
WILL GENERATE RETURN FLOW...WEAKENING THE IN SITU WEDGE DURING THE
DAY. AS THE WEDGE WEAKENS CLOUD COVER WILL DIMINISH AND AFTERNOON
TEMPERATURES ACROSS THE AREA CLIMB ABOVE CLIMO. PERIOD OF RETURN
FLOW WILL BE RATHER SHORT LIVED AS ANOTHER COLD FRONT DROPS SOUTH
ACROSS THE AREA WED NIGHT. FRONT SHOULD CLEAR THE COAST BY
MIDNIGHT...WITH ONLY POSSIBLE EXCEPTION BEING
GEORGETOWN/WILLIAMSBURG COUNTIES.
HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH BEHIND THE
FRONT...SETTING UP ANOTHER WEDGE EVENT FOR THU/THU NIGHT. MID LEVEL
PROGRESSIVE FLOW LIMITS THE COLD AIR INTRUSION...THUS LIMITING THE
STRENGTH OF THE WEDGE...BUT A CLOUDY DAY WITH HIGHS NEAR TO SLIGHTLY
BELOW CLIMO IS ON TAP. ISENTROPIC LIFT FOR THE DURATION OF THE EVENT
IS ON THE WEAK SIDE BUT SLIGHT INCREASE IN SOUTHWEST FLOW JUST ABOVE
THE SURFACE LATE THU INTO THU NIGHT COULD PRODUCE SOME PATCHES OF
DRIZZLE. HOWEVER DO NOT THINK MEASURABLE PRECIP WILL BE AN ISSUE.
CLOUD COVER AND MIXING WILL HELP KEEP LOWS ABOVE CLIMO EACH NIGHT
WITH WED NIGHT BEING THE WARMER OF THE 2 NIGHTS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 215 PM TUESDAY...CONFIDENCE ON THE LOW SIDE REGARDING THE
LONG TERM FORECAST DUE TO DISPARITIES BETWEEN GFS AND ECMWF
GUIDANCE. HAVE WEIGHTED THE FORECAST TOWARDS THE MORE RECENT AND
WARMER GFS...WHICH GIVES US A LONG TERM MARKED BY NEAR-NORMAL
DAYTIME TEMPERATURES AND ABOVE-NORMAL NIGHTTIME TEMPERATURES.
CONSENSUS OF GUIDANCE SHOWS THE PERIOD WILL SEE A RELATIVELY FLAT
UPPER PATTERN INTO SATURDAY WITH A WEAK TROUGH MOVING THROUGH ON
SUNDAY...POSSIBLY FOLLOWED BY A DEEPER TROUGH ON MONDAY OR
TUESDAY. LACK OF STRONG COLD OR WARM ADVECTION WILL MAKE FOR A
MILD EARLY DECEMBER. DEEP WESTERLY FLOW THROUGH THE PERIOD WILL
ADVECT IN PLENTIFUL MOISTURE AT THE UPPER LEVELS SO EXPECT A LONG
TERM MARKED BY PERIODS WITH A GOOD BIT OF CIRRUS PRESENT. THIS
WILL HELP MODERATE OVERNIGHT TEMPERATURES...KEEPING THEM ABOVE
AVERAGE AND IN THE 40S OR LOWER 50S. NO FREEZING TEMPERATURES ARE
EXPECTED DURING THE LONG TERM. BEST CHANCES FOR PRECIPITATION WILL
BE OVER THE WEEKEND AS A COUPLE OF WEAK FRONTAL SYSTEMS MOVE
THROUGH IN ADVANCE OF THE WEAK AND BROAD UPPER TROUGH.
&&
.AVIATION /06Z TUESDAY THROUGH SUNDAY/...
AS OF 06Z..LIFR CONDITIONS ARE BECOMING WIDESPREAD IN LOW STRATUS
AND FOG. WORST CONDITIONS EXPECTED ALONG THE COAST WHERE VLIFR
SHOULD DEVELOP, PARTICULARLY AT THE ILM AIRPORT. AFTER
DAYBREAK...ANTICIPATE CONDITIONS TO GRADUALLY IMPROVE TO MVFR BY
LATE MORNING.
EXTENDED OUTLOOK...COOL WEDGE OF HIGH PRESSURE WILL BUILD INTO THE
CAROLINAS LATE THU THROUGH FRI...BRINGING ANOTHER ROUND OF MVFR/IFR
STRATUS THROUGH SAT MORNING. MVFR/IFR CIGS MAY DEVELOP AGAIN ON SUN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM WEDNESDAY...DENSE FOG ADVISORY ISSUED THROUGH 10 AM
THIS MORNING DUE TO LOW VISIBILITIES DEVELOPING ALONG THE COAST.
NORTHEAST WINDS SHOULD CONTINUE INTO THE LATE MORNING HOURS
WEDNESDAY BEFORE VEERING MORE EASTERLY. THIS UPDATE INCORPORATES
WIND SPEED/DIRECTION FROM THE LATEST HRRR AND RUC
MODELS...DISCARDING THE GFS AND NAM WHICH INITIALIZED TOO FAR EAST
WITH THE STALLED FRONT OFFSHORE. PREVIOUS DISCUSSION FROM 930 PM
FOLLOWS...
NORTHEAST WINDS WILL BEGIN TO VEER AROUND WITH LIGHT EASTERLY FLOW
DEVELOPING OVERNIGHT AS HIGH PRESSURE TO THE DISTANT NORTH SHIFTS
EAST OVER THE CANADIAN MARITIMES. SEAS 2 TO 4 FT THIS EVENING WILL
SUBSIDE TO 2 TO 3 FT OVERNIGHT AS THE WINDS WEAKEN. LOW STRATUS DECK
EXPANDING SOUTH ALONG THE COAST COVERS MOST LOCAL WATERS RUNNING OUT
BETWEEN 20 AND 40 NM.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 215 PM TUESDAY...WEAKENING WEDGE WED WILL LEAVE AN ILL
DEFINED GRADIENT ACROSS THE WATERS DURING THE DAY. WINDS WILL BE
LIGHT WITH SPEEDS UNDER 10 KT AND GENERALLY OUT OF THE SOUTH.
PASSAGE OF COLD FRONT LATE WED NIGHT WILL INCREASE WINDS ON THU.
INITIALLY NORTHERLY FLOW WILL BE 10 TO 15 KT BUT AS THE HIGH NOSES
DOWN THE COAST THE GRADIENT WILL TIGHTEN. SPEEDS WILL INCREASE TO
15 TO 20 KT LATE THU AND THU NIGHT AS THE GRADIENT BECOMES MORE
DEFINED. SEAS WILL RUN 2 TO 4 FT WED INTO WED NIGHT. INCREASING
NORTHERLY FLOW THU AND THU NIGHT WILL PUSH SEAS TO 3 TO 5 FT LATE
THU WITH POTENTIAL FOR 6 FT THU NIGHT.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 215 PM TUESDAY...NO ADVISORIES ARE EXPECTED THROUGH THE
LONG TERM AS A WEAK PRESSURE PATTERN IS EXPECTED. HIGHEST SEAS AT
4 TO 5 FT ARE LIKELY AT THE BEGINNING OF THE PERIOD DUE TO A
COMBINATION OF A LONG FETCH OVER THE WESTERN ATLANTIC WITH A
STEADY NORTHEASTERLY WIND. A COUPLE OF WEAK FRONTAL SYSTEMS WILL
MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL INCREASE THE
CHANCES FOR RAIN...BUT OTHERWISE NO STRONG COLD SURGES ARE LIKELY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...MARINE DENSE FOG ADVISORY SURF CITY TO S SANTEE RIVER
THROUGH 10 AM TODAY.
&&
$$
NEAR TERM...RGZ/TRA
SHORT TERM...III
LONG TERM...REK
AVIATION...SGL/TRA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1252 AM EST WED DEC 3 2014
.SYNOPSIS...
A WEAK DISTURBANCE WILL MOVE OUT OF THE AREA BY WEDNESDAY MORNING.
HIGH PRESSURE WILL WORK INTO THE AREA AND KEEP DRY CONDITIONS
ACROSS THE REGION THROUGH THURSDAY MORNING. ANOTHER DISTURBANCE
WILL BEGIN TO WORK INTO THE AREA THURSDAY AFTERNOON INTO THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
WEST-SOUTHWEST MID/UPR LEVEL FLOW AHD OF DIGGING TROF WORKING FROM
THE NRN PLAINS INTO THE GREAT LAKES ON WED. DEEP MOISTURE IS OFF
TO OUR EAST BUT 00Z ILN SOUNDING SHOWS LOW LEVEL MOISTURE TRAPPED BELOW
AN INVERSION AT 825 MB. IN WEAK WAA PATTERN AREA OF DRIZZLE DEVELOPED
GENERALLY ALONG AND SE OF I-71. RAP SHOWS WEAK OMEGA IN THIS LOW LEVEL
MOIST LAYER BUT THIS LIFT DIMINISHES AND SHIFTS EAST BY 06Z. HAVE
CONTINUED MENTION OF DRIZZLE AND PATCHY DENSE FOG BUT EXPECT IMPROVEMENT
OVERNIGHT. CLOUDS TO HANG TOUGH OVERNIGHT. IN WAA PATTERN WITH
SOME INCREASE IN WINDS...TEMPERATURES TO SLOWLY RISE OR STAY QUASI-STEADY
TONIGHT.
PREV DISCUSSION...
PLENTY OF LOW LEVEL MOISTURE WILL KEEP CLOUDY CONDITIONS ACROSS
THE AREA THROUGH THE NIGHT. VISIBILITIES ARE ALSO REDUCED. THERE
IS A SUBTLE BOUNDARY SOUTH OF INTERSTATE 70. SOUTH OF THIS FEATURE
AREAS OF FOG AND PATCHY DENSE FOG ARE PRESENT. NORTH OF THIS
FEATURE VISIBILITIES ARE GENERALLY THREE MILES OR HIGHER. AS THIS
BOUNDARY MOVES OUT OF THE AREA LATER THIS EVENING INTO THE
OVERNIGHT HOURS EXPECT VISIBILITIES TO IMPROVE SOME ALTHOUGH SOME
FOG IS STILL EXPECTED DURING THE OVERNIGHT HOURS. ISSUED A SPS FOR
PATCHY DENSE FOG ACROSS THE SOUTHERN HALF OF THE FA FOR A COUPLE
HOURS THIS EVENING AND ADDED FOG MENTION INTO THE HWO.
MODELS ARE INDICATING THAT SOME VERY LIGHT DRIZZLE WILL BE
POSSIBLE ACROSS THE EASTERN PORTIONS OF THE FA THIS EVENING AND
HAVE SEEN A FEW LIGHT RETURNS ON RADAR. DO NOT EXPECT THIS TO
CAUSE MUCH IN THE WAY OF DIFFICULTIES AS TEMPERATURES ARE EXPECTED
TO BE ABOVE FREEZING WHILE THE DRIZZLE IS OCCURRING. EXPECT ANY
DRIZZLE TO MOVE OUT OF THE FA BY AROUND MIDNIGHT.
TEMPERATURES ARE EXPECTED TO REMAIN FAIRLY STEADY ACROSS THE AREA
OVERNIGHT HOWEVER SOME RISES IN TEMPERATURES BY A COUPLE OF
DEGREES WILL ALSO BE POSSIBLE...PRIMARILY ACROSS SE PORTIONS OF
THE FA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
COOLER AIR WILL WORK INTO THE FA DURING THE DAY ON WEDNESDAY.
TEMPERATURES WILL INCREASE FOR THE FIRST PART OF THE DAY HOWEVER
SOME DECREASE IN TEMPERATURES WILL BE POSSIBLE DURING THE
AFTERNOON. HIGH PRESSURE WILL WORK INTO THE AREA ALLOWING FOR DRY
CONDITIONS. CLOUD COVER WILL SLOWLY DECREASE THROUGH THE DAY AND
INTO THE EVENING HOURS ON WEDNESDAY. THIS WILL ALLOW TEMPERATURES
TO DROP OFF INTO THE 20S WEDNESDAY NIGHT.
CLOUD COVER WILL BEGIN TO INCREASE LATE WEDNESDAY NIGHT INTO THE
DAY ON THURSDAY. ISENTROPIC LIFT INCREASES AND THERE WILL BE THE
POTENTIAL FOR SOME LIGHT PRECIPITATION DEVELOPMENT ACROSS
PRIMARILY SOUTHERN PORTIONS OF THE FA THURSDAY AFTERNOON INTO THE
FIRST HALF OF THURSDAY NIGHT. BETTER PRECIPITATION CHANCES BEGIN
TO WORK INTO THE AREA BY FRIDAY MORNING. THERE IS THE POTENTIAL
FOR A BRIEF PERIOD OF A WINTRY MIX THURSDAY AFTERNOON INTO
THURSDAY NIGHT ON THE NORTHERN EDGE OF THE PRECIPITATION BEFORE
WARMER AIR WORKS INTO THE REGION AND CHANGES THE PRECIPITATION
TYPE OVER TO ALL RAIN. DECIDED NOT TO MENTION IN THE HWO AT THIS
TIME WITH SOME UNCERTAINTY ON PRECIPITATION ONSET AND HOW FAST
THE WARM AIR WILL MOVE INTO THE AREA.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
INVERTED TROUGH AND STATIONARY FRONT TAPPING INTO GULF MOISTURE WILL
BRING THE LIKELIHOOD FOR RAIN FRIDAY. A BRIEF PERIOD OF MIXED
PRECIPITATION WILL BE POSSIBLE FRIDAY MORNING BEFORE WARMER
TEMPERATURES CHANGE PRECIP TO ALL RAIN. THE LOCATION OF THE SYSTEM
SOUTH OF THE OHIO RIVER SHOULD BRING BETTER RAIN CHANCES TO THE
SOUTHERN HALF OF THE FORECAST AREA. RAIN MAY CONTINUE ON SATURDAY AS
THE SYSTEM MOVES GRADUALLY EASTWARD.
A BROAD AREA OF HIGH PRESSURE SHOULD ALLOW DRY WEATHER ON SUNDAY.
FOR MONDAY AND MONDAY NIGHT...AN UPPER TROUGH COMBINED WITH COLD
ADVECTION IN THE LOW LEVELS WILL STEEPEN LAPSE RATES ENOUGH TO
PRODUCE A CHANCE OF RAIN AND SNOW SHOWERS. MOS TEMPERATURES APPEAR
MARGINALLY COLD ENOUGH FOR SNOW BUT GUIDANCE MAY BE TOO WARM SO WENT
WITH MAINLY SNOW SHOWERS MONDAY NIGHT. HIGH PRESSURE AND A RETURN OF
DRY CONDITIONS ARE EXPECTED TUESDAY.
TEMPERATURES AS SUGGESTED BY GUIDANCE WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL...WITH HIGHS MAINLY IN THE 40S AND LOWS IN THE 30S. WENT
BELOW GUIDANCE FOR TUESDAY AS IT LOOKS LIKE WE WILL BE IN COLD
ADVECTION UNDER A NORTHERLY LOW LEVEL FLOW.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AN UPPER LEVEL TROUGH WILL TRAVERSE THE GREAT LAKES TODAY. LOW
LEVELS REMAIN FAIRLY SATURATED IN A BROAD SOUTHWEST FLOW. THIS HAS
RESULTED IN IFR/LIFR CEILINGS AND SOME MVFR VISIBILITIES.
ALSO...SOME DRIZZLE HAS DEVELOPED NEAR THE NORTHERN TAF SITES. AM
EXPECTING LOW CONDITIONS TO CONTINUE THROUGH THE NIGHT WITH
IMPROVEMENT ABOVE THE IFR CATEGORY BETWEEN 12Z AND 14Z.
THEREAFTER...WITH DAYTIME HEATING AND THE APPROACH OF A SURFACE
TROUGH...DRIER AIR WILL MOVE IN FROM THE WEST. THIS PROCESS SHOULD
HELP SCOUR AND/OR PUSH THE LOW LEVEL CLOUDS EAST BETWEEN 18Z AND
20Z. SOME GUSTY WINDS TO 20 KNOTS FROM THE WEST ARE EXPECTED AT
THE NORTHERN TAF SITES DURING THE AFTERNOON HOURS AS WELL.
FOR TONIGHT...SURFACE HIGH PRESSURE WILL BUILD SOUTHEAST INTO THE
GREAT LAKES AND THE OHIO VALLEY. WE SHOULD SEE SOME INCREASE IN
HIGH LEVEL CLOUDS THROUGH THE NIGHT.
OUTLOOK...MVFR/IFR CEILINGS AND MVFR VISIBILITIES LIKELY FRIDAY
INTO SATURDAY. MVFR CEILINGS MAY LINGER INTO SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...NOVAK
NEAR TERM...AR
SHORT TERM...NOVAK
LONG TERM...CONIGLIO
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS PORTLAND OR
857 PM PST TUE DEC 2 2014
.SYNOPSIS...OFFSHORE LOW-LEVEL FLOW WILL PEAK THIS EVENING...THEN
SLOWLY WEAKEN OVERNIGHT AND WEDNESDAY. SOME MOISTURE WILL APPROACH
FROM THE SOUTH LATE THIS EVENING...SPREADING LIGHT ACCUMULATING RAIN
FROM SOUTH TO NORTH LATE TONIGHT THROUGH WEDNESDAY MORNING. SURFACE
TEMPERATURES MAY REMAIN NEAR FREEZING AS THE PRECIPITATION ARRIVES
NEAR SALEM AND PORTIONS OF THE NORTH OREGON CASCADES AND FOOTHILLS
WITH THE POSSIBILITY OF PATCHY FREEZING RAIN. RAIN CHANCES WILL
INCREASE WEDNESDAY NIGHT AND THURSDAY AS A LOW OFF THE CENTRAL OREGON
COAST WEDNESDAY DRIFTS NORTH TO NORTHEAST. THIS WILL ALSO INCREASE
THE FREEZING RAIN THREAT FOR THE CENTRAL COLUMBIA RIVER GORGE AND THE
UPPER HOOD RIVER VALLEY WEDNESDAY EVENING THROUGH THURSDAY. FRIDAY
WILL BE MOSTLY DRY BEFORE A STRONGER FRONT ARRIVES FRIDAY EVENING.
UNSETTLED WEATHER CONTINUES THROUGH THE WEEKEND.
&&
.SHORT TERM...EVENING UPDATE...TONIGHT THROUGH FRIDAY...PRECIP IS
STARTING TO POP UP IN THE FORECAST AREA AS SEEN IN LATEST RADAR
IMAGERY THIS EVENING. LOOKING FURTHER SOUTH...3 HR PRECIP AMOUNTS
RANGE FROM 0.02" TO 0.15"...WITH THE HIGHER AMOUNTS OVER THE SOUTH
OREGON CASCADES. RAIN HAS REACHED ROSEBURG THE PAST FEW HOURS THIS
EVENING...WITH 0.01" REPORTED SO FAR. WATER VAPOR IMAGERY CONTINUES
TO PUMP THE MOISTURE NORTH INTO THE REGION TONIGHT...AND 00Z MODELS
ARE IN GOOD AGREEMENT THAT PRECIP WILL REACH AT LEAST THE CENTRAL
WILLAMETTE VALLEY OVERNIGHT. THE 00Z NAM IS SHOWING MORE SPOTTY
COVERAGE THAN THE PREVIOUS MODEL RUN...WHICH MATCHES WELL WITH
CURRENT RADAR COVERAGE ACTUALLY. PRECIP WILL BE ON THE LIGHT SIDE AS
IT LIFTS NORTH INTO OUR AREA.
AS FAR AS THE THREAT FOR FREEZING RAIN GOES...CURRENT TEMPERATURES
ACROSS THE REGION HAVE NOT DROPPED OFF AS QUICKLY AHEAD OF THE MAIN
CLOUD BAND. WITH THE MAIN BAND STARTING TO BREAK UP A BIT AND WITH
WET BULB TEMPERATURES ACROSS THE CENTRAL AND SOUTH WILLAMETTE VALLEY
STILL ABOVE FREEZING...HAVE REMOVED THE THREAT FOR FREEZING RAIN IN
THE VALLEY FOR TONIGHT. STILL LOOKING LIKE SPOTS ON THE EASTERN
SLOPES OF THE COAST RANGE WITH FREEZING TEMPERATURES COULD SEE SOME
LIGHT FREEZING RAIN. THE WARM FRONT APPEARS TO BE STALLING JUST SOUTH
OF EUGENE THIS EVENING...BUT MODELS STILL ATTEMPT TO LIFT IT FURTHER
NORTH CLOSER TO SALEM JUST AFTER MIDNIGHT. WITHOUT THE PRESENCE OF
ANY FRONTOGENESIS OR SOME SORT OF TRIGGER...RIGHT NOW IT LOOKS LIKE
IT MAY BE DIFFICULT FOR THE BOUNDARY TO REACH SALEM BUT WILL MAINTAIN
SOME LIGHT PRECIP OVER THE CENTRAL WILLAMETTE VALLEY OVERNIGHT.
EAST WINDS ALSO PERSIST OVERNIGHT WITH THE CURRENT KTTD-KDLS PRESSURE
GRADIENT AT -10.7 THIS EVENING. HAVE LOWERED OVERALL EAST WIND GUSTS
FOR TONIGHT...EXCEPT A FEW LOCAL SPOTS WILL CONTINUE TO SEE STRONGER
GUSTS INCLUDING THE TYPICAL SPOT OF CROWN POINT...WHICH HAS BEEN
GUSTING AROUND 90 MPH THE PAST SEVERAL HOURS. OVERALL EXPECT GUSTS
AROUND 60-65 MPH TO CONTINUE OVERNIGHT TONIGHT...WITH THE STRONGER
GUSTS NEAR THE WESTERN END OF THE COLUMBIA GORGE. /27
BETTER CHANCE OF FREEZING PRECIP WED NIGHT AS THE REMAINS OF THE
SURFACE LOW DRIFT INLAND. THE OFFSHORE LOW-LEVEL GORGE FLOW DOES NOT
TOTALLY GO AWAY. THUS...COLD AIR WILL REMAIN ENTRENCHED IN THE GORGE
AND UPPER HOOD RIVER VALLEY THROUGH AT LEAST THU. CONTINUED WARM
ADVECTION WED NIGHT IN THE CENTRAL WILLAMETTE VALLEY SHOULD END ANY
FREEZING RAIN THREAT THERE. SOME COLD AIR POCKETS LIKELY TO REMAIN IN
THE N OREGON CASCADE FOOTHILLS WED NIGHT FOR A CONTINUED -FZRA
THREAT. BY THU ANY -FZRA THREAT TO BE CONFINED TO THE CENTRAL GORGE
AND UPPER HOOD RIVER VALLEY. PRECIP LOOKS TO DIMINISH THU NIGHT AND
FRI MORNING. THE NEXT FRONT REACHES THE COAST FRI AFTERNOON. WEISHAAR
.LONG TERM...THE GFS AND ECMWF FAIRLY SIMILAR WITH THE LATE FRI
SYSTEM. BOTH MODELS SHOW THE SPLITTING FRONT MOVING THROUGH THE
FORECAST AREA FRI NIGHT. THIS ONE LOOKS TO BE STRONG ENOUGH TO SCOUR
OUT THE LAST OF THE COLD LOW-LEVEL AIR IN THE GORGE AND UPPER HOOD
RIVER VALLEY. 500 MB HIGH PRES AMPLIFIES SAT...WHICH COULD END UP
DRY. FOR NOW HAVE GONE WITH BELOW-CLIMO POPS BUT FURTHER SHIFTS MAY
HAVE TO CUT BACK EVEN MORE IN THE MODEL TRENDS CONTINUE. DAYTIME
TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE SEASONAL NORMS OVER THE
WEEKEND. BIGGER MODEL DIFFERENCES SUN AS THE GFS KEEPS THINGS
REASONABLY DRY THROUGH AT LEAST 18Z SUN WHILE THE ECMWF HAS
INCREASING RAIN CHANCES AS EARLY AS 12Z SUN. THE PROGRESSIVE PATTERN
CONTINUES INTO THE FIRST PART OF NEXT WEEK. WEISHAAR
&&
.AVIATION...VFR ACROSS THE BOARD AT THIS HOUR WITH A WARM FRONTAL
BOUNDARY SOMEWHAT STALLED OUT JUST SOUTH OF KEUG. HRRR MODEL WITH
SUPPORT FROM THE COARSER MODELS DO BRING THE WARM PROCESS PRECIP
NORTH OVER THE COURSE OF TONIGHT. MOST TERMINALS WILL STAY VFR
EXCEPT FOR KEUG AND PERHAPS KSLE. MET MOS IS THE MOST AGGRESSIVE
WITH CIGS DROPPING TONIGHT. ASSUMING THE BOUNDARY MOVES A LITTLE
FURTHER NORTH AS MODELS INDICATE...A LIGHT NORTHERLY WINDS WILL
KEEP LOWEST LEVELS NEAR KSLE AND KEUG STIRRED UP ENOUGH TO PREVENT
IFR CIGS FROM DEVELOPING AND MAINLY BRINGING A HIGHER END MVFR
DECK NORTH FROM THE BOUNDARY. KSLE WOULD LIKELY EASILY REMAIN VFR.
OTHERWISE...MAIN ISSUE WILL CONTINUE TO BE EASTERLY WINDS
AFFECTING KTTD AND TO A LESSER EXTENT KPDX. WINDS SHOULD BE
PEAKING NOW AND FOR THE NEXT FEW HOURS WITH GUSTS UP TO 35 KT AT
KTTD AND UP TO 30 KT AT KPDX. WINDS GENERALLY EASE LATE OVERNIGHT
AND WEDNESDAY. A WEAK OFFSHORE UPPER WAVE PUSHES NORTH CLOSER TO
04/00Z AND COULD BRING LIGHT RAIN AND A LOWER DECK INTO PLAY
ACROSS THE AREA BUT STILL SEEMINGLY HIGH END MVFR AT WORST.
KPDX AND APPROACHES...VFR WITH EASTERLY WINDS MAINLY GUSTING TO
25 KTS. OCCASIONAL 30 KT GUSTS ARE POSSIBLE UNTIL AROUND 12Z WITH
WINDS GENERALLY DECREASING THEREAFTER. VFR CONDS CONTINUE THROUGH
04/06Z ALTHOUGH A DECK AROUND 050 MAY BE IN PLACE BY LATE IN THE
AFTERNOON. /JBONK
&&
.MARINE...GAP WINDS CERTAINLY DOMINATING THE SCENARIO RIGHT NOW
WITH GUSTS PRIMARILY 25 TO 30 KT. AS SUCH...HAVE INCLUDED THE
NORTHERN INNER WATERS INTO THE ADVISORY FOR WINDS. WINDS WILL
CONTINUE LONGER ACROSS THE NORTH SO EXTENDED ALL THE NORTHERN
WATERS THROUGH 9 AM. CENTRAL WATER WINDS STILL LOOK ON TRACK TO
EASE NO LATER THAN 4 AM AND HAVE LEFT THAT AREA ALONE IN THE
ADVISORY THROUGH GAP WINDS NEAR NEWPORT AND CLOSER TO FLORENCE
WILL HAVE LOCAL INFLUENCE FOR THE CENTRAL OREGON INNER WATERS.
THE CLOSED LOW PRESSURE SYSTEM CURRENTLY OFF THE COAST OF
NORTHERN CALIFORNIA WEAKENS AS IT SLOWLY DRIFTS OFF TO THE
NORTHEAST OVER THE NEXT TWO DAYS. BEHIND THIS SYSTEM THE WEATHER
PATTERN BECOMES MORE ACTIVE AS A STRONGER SYSTEM APPROACHES ON
FRIDAY. THIS SYSTEM WILL LIKELY BRING SMALL CRAFT ADVISORY WINDS
AND SEAS. ANOTHER SYSTEM LATE THIS WEEKEND COULD POTENTIALLY BRING
GALES. LOTS OF UNCERTAINTY IN THE FORECAST EXISTS IN TIMING AND
STRENGTH OF THESE SYSTEMS AS THEY ARE FAR OUT IN THE FORECAST
PERIOD.
SEAS LOOK TO REMAIN BELOW 10 FT UNTIL FRIDAY EVENING...WHEN SEAS
BUILD AHEAD OF OUR NEXT WEATHER SYSTEM. SEAS COULD REMAIN AROUND
10 FT THROUGH THE WEEKEND AS ANOTHER SYSTEM LOOKS TO MOVE THROUGH
LATE THIS WEEKEND. JBONK/MCCOY
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 9 AM PST WEDNESDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM PST WEDNESDAY FOR
WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO 60 NM.
&&
$$
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 AUSTIN/SAN ANTONIO TX
1150 PM CST TUE DEC 2 2014
.UPDATE...
PLEASE SEE THE 06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
RECENT OBSERVATIONS SHOW CIGS CONTINUE TO LOWER ACROSS SOUTH
CENTRAL TEXAS THIS EVENING. THIS TREND WILL CONTINUE OVERNIGHT AND
THIS WILL DROP CIGS FROM MVFR TO IFR BY 08Z ALONG THE I-35
CORRIDOR. IFR CIGS TO CONTINUE THROUGH MOST OF WEDNESDAY MORNING
ALONG WITH SOME PATCHY FOG AND DRIZZLE. CIGS SHOULD MANAGE TO RISE
INTO MVFR LATE WEDNESDAY AFTERNOON BETWEEN 20Z-21Z WITH ANOTHER
DROP INTO IFR EXPECTED AFTER 04/04Z. AT KDRT...MVFR CIGS HAVE
RETURNED AND WILL CONTINUE THROUGH EARLY WEDNESDAY MORNING. WE/LL
GO AHEAD AND BRING CIGS DOWN INTO IFR BEGINNING 12Z. MVFR CIGS
SHOULD RETURN AFTER 03/17Z...WITH PERHAPS A FEW BREAKS TO VFR
BETWEEN 03/22Z-04/02Z. CIGS DROP BACK INTO MVFR AROUND 04/04Z.
&&
.PREV DISCUSSION... /ISSUED 944 PM CST TUE DEC 2 2014/
UPDATE... ONLY A FEW EDITS WERE MADE TO GOING FORECAST WITH SLIGHT
TRIMMING BACK OF PATCHY DRIZZLE AREA TO JUST THE FAR SOUTHERN
COUNTIES NOW THROUGH MIDNIGHT. HOURLY TEMPERATURES/ DEWPOINTS WERE
ON TRACK WITH ONLY SLIGHT ADJUSTMENTS MADE FOR OBSERVATIONAL TRENDS.
DISCUSSION... LOW CLOUDS REMAIN ACROSS MUCH OF THE REGION WITH
THE SOLE EXCEPTION OF VAL VERDE COUNTY THIS EVENING. YET, EXPECT
THIS REGION TO ALSO FILL IN THROUGH THE OVERNIGHT BASED ON LATEST
SATELLITE TRENDS. BASED ON LATEST HI-RES RAP AND NAM/GFS BUFR
SOUNDINGS INDICATING DRIER AIR IN THE LOWEST 1000FT THAT WILL
LIKELY NEED TO BE OVERCOME FOR ANY LIGHT DRIZZLE TO MAKE IT ALL
THE WAY TO THE SURFACE. FORECAST SOUNDINGS DO MOISTEN UP AFTER
MIDNIGHT TOWARDS 3-6AM AND THIS COMBINED WITH WEAK ISENTROPIC
LIFT COULD HELP LIGHT PATCHY DRIZZLE DEVELOP OVER I-35 CORRIDOR
AND AREAS EAST. STILL, NO ACCUMULATIONS ARE EXPECTED WITH NO
IMPACTS ANTICIPATED. HAVE KEPT POPS LOW, IN THE 10% RANGE. UPDATED
TEXT PRODUCTS ARE OUT AND WILL CONTINUE GRAPHICS AS IS GIVEN THE
OVERNIGHT EXPECTATIONS. /ALLEN/
PREV DISCUSSION... /ISSUED 338 PM CST TUE DEC 2 2014/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
A SHALLOW COOL AIR MASS WILL ERODE OVER THE NEXT 24-36 HOURS.
AREAS OF LIGHT DRIZZLE AND SPRINKLES HAD DEVELOPED GENERALLY SOUTH
OF HIGHWAY 90 EARLIER TODAY AND THEN TAPERED OFF IN THE AFTERNOON.
THIS WEAK ISENTROPIC LIFT SHOULD RESUME LATER THIS EVENING INTO
WEDNESDAY MORNING WITH LIGHT RAIN OR SPRINKLES POSSIBLE INTO THE
AFTERNOON. THE PRECIPITATION IS NOT LIKELY TO BE CONTINUOUS...BUT
THE STEADY ZONAL FLOW PATTERN ALOFT WILL MAKE IT DIFFICULT TO PIN
DOWN THE TIMING OF BETTER RAIN CHANCES. THE THICK LOW LEVEL MOIST
LAYER SHOULD LIMIT THE POTENTIAL FOR DAYTIME HEATING...ALTHOUGH
THE RETURN OF SOUTHERLY WINDS WEDNESDAY SHOULD REDUCE THE
ISENTROPIC EFFECTS ALONG THE INVERSION AND ALLOW FOR A FEW BREAKS
IN THE CLOUDS WEDNESDAY.
LONG TERM (THURSDAY THROUGH TUESDAY)...
A DREARY PATTERN WITH LIGHT SHOWERS AND OR PATCHY DRIZZLE REMAINS
POSSIBLE THROUGH MUCH OF THE EXTENDED FORECAST AS FLOW REMAINS
ZONAL ALOFT. MOISTURE DEPTH IS EXPECTED TO INCREASE ON FRIDAY...
ESPECIALLY OVER THE COASTAL PLAINS WHERE THE NAM/GFS PWAT VALUES
APPROACH 1.5 INCHES. DPROG/DT OF THE GFS SUGGESTS SLIGHT
STRENGTHENING OF A SHORTWAVE LATE FRIDAY...AND A STRENGTHENING OF
A COLD FRONT TO FOLLOW. CHANGES AS APPLIED TO THIS FORECAST WERE
SUBTLE...WITH A SLIGHT LOWERING OF BOTH HIGHS AND LOWS OVER THE
WEEKEND. ANOTHER SHORTWAVE IS QUICK TO FOLLOW FOR SUNDAY WITH
SLIGHTLY ENHANCED RAIN CHANCES LATE SUNDAY/SUNDAY NIGHT. SHOULD
THE SHORTWAVE ACTIVITY AMPLIFY FURTHER...SOME BREAKS IN THE
OVERCAST COULD DEVELOP IN THE WAKES OF THE FRIDAY NIGHT AND SUNDAY
NIGHT DISTURBANCES.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 47 64 55 68 59 / 10 10 20 20 20
AUSTIN BERGSTROM INTL AIRPORT 46 63 54 68 59 / 10 10 20 20 20
NEW BRAUNFELS MUNI AIRPORT 48 65 56 69 61 / 10 10 20 20 20
BURNET MUNI AIRPORT 45 63 52 66 57 / 10 10 20 20 20
DEL RIO INTL AIRPORT 46 63 54 67 57 / - 10 20 10 20
GEORGETOWN MUNI AIRPORT 46 63 53 67 58 / 10 10 20 20 20
HONDO MUNI AIRPORT 47 61 55 68 59 / 10 10 20 20 20
SAN MARCOS MUNI AIRPORT 47 64 54 69 59 / 10 10 20 20 20
LA GRANGE - FAYETTE REGIONAL 49 67 55 71 61 / 10 10 20 20 20
SAN ANTONIO INTL AIRPORT 49 63 57 69 61 / 10 10 20 20 20
STINSON MUNI AIRPORT 48 64 57 69 62 / 10 10 20 20 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1008 PM MST TUE DEC 2 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 251 PM MST TUE DEC 2 2014
A STRONG COLD FRONT CONTINUES TO PUSH SOUTH ACROSS THE CWA LATE THIS
AFTERNOON. RECENT SFC OBSERVATIONS INDICATE THIS FEATURE WAS LOCATED
JUST NORTH OF THE I80 CORRIDOR AT 20Z. WEAKENING GRADIENTS FOLLOWING
THE FRONTAL PASSAGE HAVE GENERALLY LIMITED WIND GUSTS...BUT STILL IS
QUITE WINDY ACROSS THE WIND PRONE LOCATIONS OF SOUTHEAST WYOMING AND
THE ADJACENT PLAINS. GOOD MIXING TODAY WITH AMPLE SUNSHINE...AND THE
CYS VAD WIND PROFILE STILL SHOWS 45 KT WINDS JUST 2K FEET AGL. STILL
MAY SEE A FEW GUSTS APPROACH 50 MPH THROUGH ABOUT 00Z...ESPECIALLY
IN THE WIND PRONE AREAS AND LOWER ELEVATIONS ALONG/AHEAD OF THE COLD
FRONT. NO WIND CONCERNS OVERNIGHT AS GFS/NAM SHOW H8-H7 FLOW FALLING
CONSIDERABLY AFTER 00Z WED. EXPECTED MORE MOISTURE TO ADVECT IN FROM
THE NORTH TODAY BEHIND THE FRONT...BUT VISIBLE SATELLITE HAS SHOWN
MOSTLY SUNNY SKIES THROUGH MOST OF THE DAY WITH LOWER CLOUDS ERODING
OVER NORTHEAST WY. SHOULD SEE STRATUS DEVELOP ALONG AND EAST OF THE
LARAMIE RANGE LATER TONIGHT AS THE BLYR COOLS AND WEAK LLVL UPSLOPE
TAKES SHAPE. ADDED SOME PATCHY FOG FROM THE SUMMIT EAST INTO CENTRAL
LARAMIE COUNTY WITH MODEST LIFT AND NAM SOUNDING PROGS SHOWING GOOD
SATURATION IN THE LLVLS BETWEEN 09-12Z. LIMITING FACTOR FOR FOG PTNL
WOULD BE IF WINDS STAY STRONG ENOUGH TO KEEP THINGS MIXED NEAR THE
SFC.
MUCH COOLER FOR WED IN THE POST-FRONTAL AIR MASS. H7 TEMPS AVERAGING
AROUND -5 DEG C AND POTENTIAL FOR WIDESPREAD CLOUDS SUGGEST SENSIBLE
TEMPERATURES WILL BE A BIT COOLER THAN GUIDANCE. MODELS KEEP A SOUTH
WIND INTACT FOR CHEYENNE FOR MOST OF THE DAY ON WED...SO IT WOULD BE
DIFFICULT TO SCOUR OUT LLVL CLOUDS BY PEAK HEATING. DROPPED HIGHS A
FEW DEGREES AS IT MAY BE TOUGH TO EVEN REACH 40 DEGREES LOCALLY. TOO
DRY ALOFT TO SUPPORT PCPN OUTSIDE OF THE MOUNTAINS. LARGE SCALE LIFT
IMPROVES BY WED AFTERNOON IN THE LEFT EXIT REGION OF A 110+ KT H25
JET STREAK OVER CENTRAL UT. PVA AND MOIST LLVL OROGRAPHICS WILL ALSO
SUPPORT ACCUMULATING SNOWFALL IN THE MOUNTAINS AND A FEW OF THE ADJ
VALLEYS FROM WED AFTN THROUGH THE DAY ON THU. CURRENTLY EXPECT SUB-
ADVISORY AMOUNTS WITH 2-4 INCHES IN THE SNOWIES/SIERRA MADRES AS QPF
IS UNIMPRESSIVE. DOWNSLOPE FLOW RETURNS TO THE EASTERN PLAINS ON THU
LIKELY PROVIDING A GOOD BOOST TO TEMPERATURES. TRENDED TOWARD WARMER
MOS GUIDANCE WITH A FEW 60 DEGREE READINGS POSSIBLE.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 251 PM MST TUE DEC 2 2014
A SPLIT FLOW PATTERN THROUGH THIS PORTION OF THE FORECAST WILL
YIELD LITTLE TO NO CHANCE FOR PRECIPITATION ALONG WITH TEMPS THAT
WILL AVERAGE AROUND 10F ABOVE SEASONAL NORMS. MUCH OF THE CENTRAL
ROCKIES WILL BE CAUGHT BETWEEN THE NORTHERN STREAM JET WHICH WILL
MEANDER AROUND SRN CANADA/NRN CONUS AND A SUB-TROPICAL JET THAT
WILL HOLD UP WELL SOUTH OF THE AREA. PERIODIC SHORTWAVE TROUGHS
WILL TRAVERSE THE FLOW...BUT WILL TRACK TO THE NORTH AND SOUTH OF
THE REGION ALONG EACH JET. ALTHOUGH DONT SEE ANY WIDESPREAD HIGH
WIND EVENTS DURING THE PERIOD...BREEZY CONDITIONS WILL PREVAIL
MAINLY IN AND AROUND THE SOUTHEAST WYOMING MOUNTAINS. OTHERWISE...
EXPECT HIGH TEMPERATURES TO REACH THE 40S AND LOWER 50S EACH
AFTERNOON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1005 PM MST TUE DEC 2 2014
KEPT CONDITIONS VFR FOR THE 06Z TAF SUITE. LOOKING AT UPSTREAM
OBSERVATIONS TO OUR NORTHEAST...DEWPOINTS REALLY LOW OUT OVER THE
PANHANDLE WITH NO LOW STRATUS DEVELOPMENT SEEN ON SATELLITE
IMAGERY. SREF AND LATEST HRRR SUPPORT VFR CONDITIONS AS WELL.
&&
.FIRE WEATHER...
ISSUED AT 251 PM MST TUE DEC 2 2014
NO FIRE WEATHER CONCERNS. A COLD FRONT WILL MOVE SOUTH INTO NORTHERN
COLORADO THIS EVENING WITH WINDS DIMINISHING OVERNIGHT. IT WILL BE A
COOLER ON WED WITH A FEW INCHES OF MOUNTAIN SNOW POSSIBLE. A WARMING
TREND IS EXPECTED LATER IN THE WEEK WITH TEMPERATURES IN THE 50S TO
NEAR 60 DEGREES EAST OF THE LARAMIE RANGE ON THU. CONTINUING BREEZY
IN THE AFTERNOONS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...CLH
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS POCATELLO ID
854 AM MST WED DEC 3 2014
.UPDATE...FIRST OF SEVERAL WAVES OF PRECIP MOVING THROUGH EAST
IDAHO THIS MORNING PER RADAR IMAGERY. HRRR WET BULB ZERO HEIGHT
FIELD SEEMS TO ACCURATELY MATCH BREAK POINT BETWEEN RAIN/SNOW PER
MESONET SFC OBS AND AREA WEB CAMS. BRIEF BREAK THIS AFTERNOON WITH
NEXT BATCH MOVING IN TO WESTERN EDGES BY EARLY EVENING AT LEAST
PER HRRR. NAM/SREF/GFS/RAP ALL ALSO SIMILAR WITH THIS DEPICTION AS
WELL WITH CURRENT BAND MOVING INTO NORTHEAST CORNER THIS AFTERNOON
AND SECOND BATCH REACHING SOUTHWEST CORNER AT SAME TIME. SPLIT
POPS DOWN A BIT FURTHER AND TRIED TO PROGRESS POP FOCUS PER THIS
SCENARIO. QPF AND SNOW AMOUNTS APPEAR TO BE IN THE BALLPARK FOR
TODAY. DMH
&&
.PREV DISCUSSION... /ISSUED 333 AM MST WED DEC 3 2014/
SHORT TERM...TODAY THROUGH FRIDAY AFTERNOON. THE LOW CONTINUES TO
CHURN ALONG THE WEST COAST THIS MORNING. THIS HAS SENT QUITE A BIT
OF CLOUD COVER OVER EASTERN IDAHO THIS MORNING. THERE IS A CLEAR
SLOT RIGHT NOW WORKING EAST ACROSS THE SOUTHERN HALF OF OUR AREA
BUT THAT SHOULD EVENTUALLY WORK EAST OVER THE NEXT FEW HOURS.
PRECIPITATION IS BEGINNING TO MOVE INTO THE MAGIC VALLEY AND
CENTRAL MOUNTAINS. WE ARE STILL DEALING WITH SOME LOW CLOUDS AND
FOG ACROSS PORTIONS OF THE SNAKE PLAIN AND ADJACENT VALLEYS...BUT
THAT SHOULD BE GONE BY MID MORNING AT THE LATEST. FOR TODAY...WE
WILL SEE THE BAND OF PRECIPITATION SHIFTING NORTHEAST BUT ALSO
WEAKENING AS IT DOES. THE MODELS ARE ALL OVER THE PLACE EVEN FOR
TODAY AT THIS LATE STAGE. WE CURRENTLY HAVE THE HIGHEST PRECIPITATION
AMOUNTS ACROSS THE WESTERN CENTRAL MOUNTAINS AND ACROSS THE
SOUTHERN MOUNTAINS. HOWEVER...BASED ON THE CURRENT TRAJECTORY WE
MIGHT NEED TO UP AMOUNTS FARTHER NORTHEAST TOWARDS ARCO AND
EVENTUALLY THE UPPER SNAKE HIGHLANDS. AMOUNTS TO THE SOUTH WILL
DEPEND ON HOW QUICKLY THE DRY SLOT WORKS EAST AND THE NEXT SURGE
MOVES IN. SNOW LEVELS WILL CONTINUE TO RISE AND REACH 5000-6000FT
FOR MOST AREAS WITH LEVELS CLOSER TO 6500FT ACROSS THE SOUTH AND
ALSO THE WESTERN CENTRAL MOUNTAINS. ANY CONCERN FOR FREEZING
RAIN/DRIZZLE IMPACT IS LOW AT THIS POINT. IF IT DOES HAPPEN...IT
WILL BE ISOLATED POCKETS WHERE THE COLDER AIR TAKE A BIT LONGER TO
SCOUR OUT OR ALONG THE LEADING EDGE OF THE PRECIPITATION ACROSS
THE SNAKE PLAIN. GUSTY SOUTHERLY WINDS WILL DEVELOP LATER TODAY.
WITH SNOW IN THE MOUNTAINS...WE SHOULD SEE SOME POCKETS OF
BLOWING SNOW BUT IMPACTS ARE NOT EXPECTED TO BE HIGH/MAJOR WITH
WARMER TEMPERATURES. THE MODELS STILL STRUGGLE WITH WHERE TO PLACE
RAIN/SNOW ACROSS THE REGION TONIGHT...MAINLY WITH A POTENTIAL BAND
ACROSS THE LOWER SNAKE PLAIN AND MAGIC VALLEY. THE LATEST RUNS DO
HINT AT IT BUT CONFIDENCE ON HOW MUCH WILL FALL IS NOT THERE. WE
DID FOCUS ON HIGHER CHANCES AND AMOUNTS FOR THE CENTRAL MOUNTAINS
AND UPPER SNAKE HIGHLANDS AS THERE IS CONTINUED SIGNS OF UPSLOPE
CONDITIONS AND EVERYTHING SHIFTING NORTH. THAT TREND CONTINUES
TOMORROW WITH SOME SHOWERS POSSIBLE ELSEWHERE. IF THE CURRENT
MODEL TRENDS REMAIN...THE REST OF EASTERN IDAHO MAY END UP MUCH
DRIER THAN CURRENTLY SHOWN. SNOW LEVELS CONTINUE TO CREEP
HIGHER...PEAKING AT 6000-7000FT IN THE AFTERNOON. WINDS WILL BE
GRADUALLY WEAKENING DURING THAT PERIOD. SNOW AMOUNTS FOR THE NEXT
24-36 HOURS ARE NOT TOO IMPRESSIVE...IN THE 1-5 INCH RANGE. A FEW
LOCATIONS UP REALLY HIGH BETWEEN HAILEY AND STANLEY AND BORDERING
YELLOWSTONE COULD SEE ANOTHER 2-4 INCHES. IMPACTS WILL BE LOWER
AND NOT WIDESPREAD...SO NO HEADLINES WILL BE ISSUED AT THIS POINT.
HEADING INTO FRIDAY...HIGH PRESSURE WILL BUILD FROM THE SOUTH
HELPING US TO DRY OUT. THE POTENTIAL FOR SOME STRATUS...FOG AND
VERY LIGHT DRIZZLE/FLURRIES IS THERE FOR PORTIONS OF THE UPPER
SNAKE PLAIN AND TOWARD THE MONTANA BORDER. OTHERWISE...A MIX OF
SUN AND CLOUDS IS ON TAP WITH WARM WEATHER STICKING AROUND. KEYES
LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. WITH RESPECT TO THE
DISTURBANCE ENTERING THE PACIFIC NORTHWEST ON SATURDAY...THE 03/00Z
EUROPEAN MODEL RUN HAS MADE A SHIFT BRINGING IT MORE IN LINE WITH
THE GFS. LOOKS LIKE THE DISTURBANCE WILL TRACK THROUGH CENTRAL AND
NORTHERN IDAHO DURING THE DAY SATURDAY...AND THROUGH ISLAND PARK AND
DRIGGS AREA LATE AFTERNOON AND EVENING. SNOW LEVELS REMAIN ELEVATED
BETWEEN 6000-6500 FEET ELEVATION...ABOUT 1 TO 3 INCHES ACCUMULATION
ABOVE THAT LEVEL. MODEL AGREEMENT CONTINUES MONDAY WITH A HIGH PRESSURE
RIDGE TRANSITIONING THROUGH THIS AREA AND PROVIDING A BREAK IN THE
WEATHER. THE NEXT DISTURBANCE COMES INLAND MONDAY AFTERNOON AND
NIGHT. THE EUROPEAN MODEL SHOWS A LITTLE MORE HIGH PRESSURE RIDGE ON
TUESDAY AND IS MUCH DRIER THAN THE GFS. THE GFS SOLUTION IS ALMOST A
REPEAT OF THE SATURDAY DISTURBANCE. SNOW LEVELS REMAIN ELEVATED
THROUGH THE WEEK AND VALLEY TEMPERATURES PERSIST IN THE 40S. RS
AVIATION...STRATUS AND PATCHY FOG HAS PERSISTED THROUGH LAST NIGHT
IN THE SNAKE PLAIN. LIGHT RAIN ASSOCIATED WITH THE LOW OFF NORTHERN
CALIFORNIA IS ALREADY MOVING THROUGH TWIN FALLS THIS MORNING.
BETWEEN 15Z AND 18Z LOOKING FOR WINDS TO SHIFT MORE SOUTH-SOUTHWEST
WHICH WILL HELP DECREASE THE CHANCE OF FREEZING PRECIPITATION
QUICKLY. KBYI IS ALREADY ABOVE FREEZING AND ONCE THE WINDS
TURN...TEMPERATURES SHOULD POP BACK ABOVE FREEZING AT KPIH AND KIDA.
EVEN KSUN IS JUST BARELY HOLDING NEAR 32F FOR A COUPLE HOURS THIS
MORNING. DOES NOT LOOK LIKE WE WILL LOOSE THE CLOUDS AND PATCHY FOG
TONIGHT BUT AT LEAST LOOSE THE LIFR CONDITIONS IN FAVOR OF MORE MVFR
CEILINGS. RS
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
511 AM CST WED DEC 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 327 AM CST WED DEC 3 2014
A WEAK AREA OF ARCTIC HIGH PRESSURE ACROSS ERN
MT WILL BUILD SOUTHEAST AND FUSE WITH THE MODIFIED ARCTIC HIGH
ACROSS WRN NEB THIS MORNING. THE RESULT IS A DRY 1030MB HIGH WHICH
THEN MOVES EAST TODAY AND TONIGHT SETTING UP A RETURN FLOW. BY 12Z
THURSDAY WARM AIR HAS RETURNED TO THE FCST AREA WITH SFC LOW
PRESSURE OVER SCNTL SD. DEWPOINTS HAVE ALREADY BEEN ADJUSTED DOWN
TOWARD THE VERY DRY RAP MODEL WHICH PRODUCES DEWPOINTS IN THE SINGLE
DIGITS TODAY. THE TEMPERATURE FORECAST IS BASED SOLELY ON BIAS
CORRECTED MET...MAV AND ECS GUIDANCE FOR HIGHS CLOSE TO WHAT THE RAP
INDICATES...UPPER 30S TO LOWER 40S. A BATCH OF MID AND HIGH LEVEL
CLOUDS ACROSS THE COLORADO LIFTS EAST NORTHEAST TODAY. THE MODEL
CONSENSUS SUGGESTS THE DENSER MID LEVEL CLOUDS WOULD MOVE MOSTLY
ACROSS NWRN NEB THIS AFTN WITH SKIES CLEARING EARLY THURSDAY MORNING.
A SIMILAR STRATEGY IS IN PLACE TONIGHT FOR BIAS CORRECTED LOWS IN
THE TEENS AND 20S. THE STRONG RETURN FLOW SPENDS THE NIGHT WORKING
ITS WAY ACROSS THE FCST AREA LIMITING RADIATIONAL COOLING TO THE FEW
HOURS TOWARD MORNING WHEREBY WINDS WOULD DECOUPLE ACROSS SRN NEB BUT
REMAIN STRONG IN THE NORTHEAST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 327 AM CST WED DEC 3 2014
DRY WEATHER WILL CONTINUE THROUGH THE PERIOD ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA. A WESTERLY DOWNSLOPE CHINOOK WIND WILL
ADVECT 8 TO 10C H850 MB TEMPERATURES EASTWARD ACROSS THE AREA
THURSDAY. AS THIS AIR IS MIXED TO THE SURFACE...HIGHS SHOULD BE
WELL INTO THE 50S ACROSS WESTERN NEBRASKA...WITH 45 TO 52F FOR
AREAS FARTHER EAST. DESPITE THE WARMER AIR...FIRE WEATHER
CONDITIONS WILL REMAIN IN CHECK...AS SOME PACIFIC MOISTURE ACTUALLY
MAKES IT EAST OVER THE ROCKIES WITH DEW POINTS IN THE MID 20S TO
AROUND 30 DEGREES.
FOR FRIDAY AND THE WEEKEND...A COUPLE OF WEAK SYSTEMS WILL MOVE
ACROSS SOUTHERN CANADA. THIS WILL DRIVE A WEAK COLD FRONT SOUTH
INTO THE AREA FRIDAY. THE FRONT WILL LIFT BACK NORTH INTO THE
NORTHERN PLAINS AS A WARM FRONT SATURDAY AND SUNDAY...WITH A MILD
WEEKEND EXPECTED FOR OUR AREA. A STRONGER ALBERTA CLIPPER WILL
DIVE SOUTHEAST SUNDAY NIGHT INTO MONDAY ACROSS NORTH DAKOTA INTO
NORTHERN MINNESOTA. THIS COULD SEND A SHOT OF ARCTIC AIR INTO
NORTH CENTRAL THROUGH EASTERN NEBRASKA MONDAY. THIS WILL BE BRIEF
HOWEVER...WITH A RAPID RETURN OF SOUTHERLY WINDS AND WARMING
TEMPERATURES TUESDAY INTO WEDNESDAY AS ANOTHER PLUM OF WARM AIR
ALOFT MOVES EAST OFF THE HIGHER TERRAIN TO THE WEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 511 AM CST WED DEC 3 2014
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT.
MID AND HIGH CLOUDINESS ASSOCIATED WITH A WARM FRONT ACROSS
COLORADO THIS MORNING WILL SPREAD SLOWLY EAST NORTHEAST TODAY AND
TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1000 AM EST WED DEC 03 2014
.SYNOPSIS...A STALLED FRONT TO THE SOUTH WILL LIFT BACK TO THE NORTH
AS A WARM FRONT THIS AFTERNOON...IN ADVANCE OF A COLD FRONT
APPROACHING THE MOUNTAINS FROM THE NORTHWEST. THE COLD FRONT WILL
SURGE SOUTHWARD INTO THE CAROLINAS TONIGHT. DRY HIGH PRESSURE WILL
BUILD INTO THE REGION FROM THE NORTH ON THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...
THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE OVER CENTRAL NORTH
CAROLINA WITH A SURFACE FRONT STALLED FOR NOW AGAINST THE
MOUNTAINS...AND A WEAK...DIFFUSE BOUNDARY WELL TO OUR SOUTH. CLOUDS
WERE WIDESPREAD OVER THE AREA...AND WHILE OBSERVATIONS WERE SHOWING
THE VISIBILITIES IN THE FOG SLOWLY IMPROVING...THERE WAS A GOOD
INVERSION ON THE KGSO SOUNDING EMPHASIZED BY THE RELATIVE WARMTH TO
ABOVE 10C NEAR 900MB AND ON THE KRNK SOUNDING AS WELL SHOWING NEAR
10C AT 850MB. WITH THAT INVERSION IN PLACE...THINK THE CLEARING
SHOULD BE SLOW. THE GFS IS FASTER WITH THE CLEARING...WITH ITS BUFR
SOUNDINGS INDICATING NUMEROUS BREAKS LIKELY BY 18Z...WHILE THE NAM
BUFR SOUNDINGS WOULD INDICATE MORE BETWEEN 18Z AND 21Z. THE LATTER
IS MORE CONSISTENT WITH THE LATEST HRRR WRF GUIDANCE...AND FOR THE
UPDATE IN THE GRIDDED FORECAST WAS A LITTLE MORE PESSIMISTIC AND
HELD ONTO MORE CLOUDS INTO THE AFTERNOON EVEN TOWARD THE SANDHILLS
AND SOUTHERN COASTAL PLAIN. WHILE THE RAP FORECAST A MODEST MID-
LEVEL WAVE MOVING THROUGH SOUTHERN VIRGINIA THIS AFTERNOON...LIFT
WAS WEAK AND MID-LEVEL MOISTURE WEAK AS WELL...SO PRECIPITATION
CHANCES WILL BE BELOW SLIGHT SAVE FOR STILL LIMITED POTENTIAL OF
SPOTTY DRIZZLE THIS MORNING. LEANED TOWARD THE COOLER MET MOS
GUIDANCE FOR HIGHS THIS AFTERNOON...WHICH IS WELL ON THE COLD END OF
THE GUIDANCE SUITE BUT CONSISTENT WITH THE PREVIOUS FORECAST. EDGED
THE FORECAST A LITTLE COOLER IN THE SANDHILLS AND COASTAL
PLAIN...ANTICIPATING CURRENTLY LATE-DAY HIGHS APPROACHING 60 IN THE
FAR NORTHWEST PIEDMONT...AND 60 TO 65 ELSEWHERE. WITH THE SOUTHWEST
FLOW IN PLACE...SEEN EVEN ON THE LOWEST GATE OF THE WSR-88D VWP AND
IN PROFILER DATA...ANY EVEN THIN SPOTS IN THE OVERCAST SHOULD RESULT
IN QUICK WARMING. -DJF
TEMPS THIS EVENING WILL BE A FUNCTION OF CLOUD COVER...FOLLOWED BY
COLD ADVECTION TONIGHT AS A COLD FRONT SURGES INTO CENTRAL NC FROM
THE N/NW. THE LATEST GUIDANCE SUGGESTS FROPA MAY OCCUR AS EARLY AS
03-06Z...WITH A GOOD 6-9 HOURS OF COLD ADVECTION PRIOR TO SUNRISE.
EXPECT LOWS RANGING FROM ~40F NEAR THE VA BORDER TO MID/UPPER 40S
NEAR THE SC BORDER. -VINCENT
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 330 AM WEDNESDAY...
LOW OVERCAST PREVIOUSLY PROGGED TO DEVELOP FROM THE SOUTH (OR FROM
SW-NE) MID TO LATE THU MORNING IN THE WAKE OF THE BACKDOOR COLD
FRONT APPEARS INCREASINGLY UNLIKELY TO OCCUR DUE TO LIGHT SOUTHERLY
FLOW /MARGINAL WARM ADVECTION/ ATOP THE SHALLOW COLDER AIRMASS
ADVANCING INTO THE REGION FROM THE NORTH. REGARDLESS...BROKEN/
OVERCAST CEILINGS AT ~15 KFT ARE EXPECTED TO MOVE INTO THE REGION
FROM THE WEST THROUGHOUT THE DAY...RESULTING IN MOSTLY CLOUDY SKIES
AND...ULTIMATELY...LITTLE DIURNAL VARIATION WITH HIGHS IN THE
MID/UPPER 40S AND LOWS THU NIGHT IN THE LOWER 40S. -VINCENT
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...
THE ROLLER COASTER RIDE IN TEMPERATURES SHOULD CONTINUE INTO NEXT
WEEK...
A WHOLE HOST OF PACIFIC STORM SYSTEMS ARE EXPECTED TO DRIVE INTO THE
WEST COAST... THEN ENCOUNTER A A SPLIT FLOW PATTERN AS THEY COME
EASTWARD FROM THE ROCKIES TO THE MID-ATLANTIC COAST. IT IS STILL
UNCLEAR IF ANY PHASING OF THE TWO JETS (THE POLAR JET AND THE ACTIVE
SUBTROPICAL JET) WILL OCCUR OVER THE EASTERN UNITED STATES DURING
THIS PERIOD. THE CONSENSUS IS FOR THE SUBTROPICAL JET TO REMAIN THE
MORE DOMINATE FLOW... WITH AT LEAST SOME PHASING OF THE FLOW THAT
WOULD MOST LIKELY BE OFFSHORE IN THE ATLANTIC EARLY TO MID NEXT
WEEK.
REGARDLESS... THE MID AND UPPER LEVEL SPLIT FLOW PATTERN WITH A
RELATIVELY DOMINATE SUBTROPICAL FLOW OVER OUR REGION FAVORS A STORM
TRACK THAT WOULD DELIVER THE MOST SIGNIFICANT RAINS TO THE TENNESSEE
VALLEY INTO THE APPALACHIANS TO THE MID-ATLANTIC COAST LATE FRIDAY
INTO SUNDAY. THIS WOULD INCLUDE AT LEAST THE NW QUADRANT OF OUR
REGION... IF NOT MOST FOR AT LEAST SOME DECENT RAINFALL OVER THE
WEEKEND.
WE WILL BEGIN THE FORECAST BASED ON HPC MODEL PREFERENCES INCLUDING
THE LATEST 00Z/03 DECEMBER OPERATIONAL EC AND GFS RUNS THAT
INDICATE THE PROGRESSION OF THE WET SYSTEMS FROM WEST TO EAST BUT
KEEP SOME SEPARATION IN THE TWO JET STREAMS INTACT THROUGH SUNDAY.
OUR SENSIBLE WEATHER HIGHLIGHTS INCLUDE ANOTHER CAD EVENT FOR THE
WEEKEND POSSIBLY ENHANCED AND PROLONGED BY THE MID/UPPER TROUGH THAT
IS EXPECTED TO PUSH INTO THE APPALACHIANS BY LATER SATURDAY... THEN
CROSS THE REGION SUNDAY. EXPECT PLENTY OF CLOUDS FRIDAY... THEN
OVERCAST CONDITIONS SAT-SUN WITH A GOOD CHANCE OF RAIN. TEMPS LIKELY
COLDER THAN GUIDANCE BY 5-7 DEGREES DURING THE DAY SAT AND SUN
YIELDING MOSTLY MID 40S TO MID 50S NW TO S.
BY MON-WED... THE SYSTEM IS EXPECTED TO PUSH OFFSHORE BY EARLY
MONDAY ALLOWING FOR CLEARING WITH A BIT MILDER TEMPERATURES BACK
INTO THE MID 50S TO LOWER 60S EARLY NEXT WEEK.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 615 AM WEDNESDAY...
24-HR TAF PERIOD: LIFR/VLIFR CEILINGS AND VISBYS THIS MORNING WILL
GRADUALLY IMPROVE TO MVFR AND PERHAPS VFR THIS AFTERNOON AS THE COLD
AIR DAMMING WEDGE IN PLACE ERODES FROM SOUTH TO NORTH IN ASSOC/W
STRENGTHENING SOUTHWESTERLY FLOW IN THE LOWER LEVELS. AS TYPICAL
WITH THIS TYPE OF SETUP...CONFIDENCE IN THE TIMING OF SAID
IMPROVEMENT REMAINS BELOW AVERAGE...ESP AT THE INT/GSO TERMINALS.
ONCE CEILINGS LIFT TO MVFR/VFR THIS AFTERNOON...MVFR/VFR CONDITIONS
SHOULD PREVAIL THEREAFTER AS ANOTHER BACK DOOR COLD FRONT
APPROACHES/SURGES INTO THE REGION FROM THE N/NW...ADVECTING A DRIER
LOW-LEVEL AIRMASS INTO CENTRAL NC. EXPECT WINDS TO SHIFT TO THE
NORTH AT 5-10 KT IN THE WAKE OF THE FRONT BETWEEN 00-06Z FRI...
BECOMING NORTHEAST AND INCREASING TO 10-15 KT BY 12Z FRI.
LOOKING AHEAD: BELOW AVERAGE CONFIDENCE PERSISTS THROUGH THE
WEEKEND. MVFR/IFR CEILINGS ARE EXPECTED TO RE-DEVELOP THU NIGHT/FRI
AND PERSIST (POSSIBLY) THROUGH THE WEEKEND IN ASSOCIATION WITH
THE DEVELOPMENT OF ANOTHER COLD AIR DAMMING WEDGE. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF/VINCENT
SHORT TERM...VINCENT
LONG TERM...PWB
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
922 AM EST WED DEC 3 2014
.SYNOPSIS...
HIGH PRESSURE TO OUR NORTH WILL BRING CLOUDY AND COOL WEATHER
THROUGH FRIDAY. AFTER A ONE DAY WARM-UP ON SATURDAY A NEW HIGH
WILL BUILD IN FROM THE NORTH AGAIN ON SUNDAY...BRINGING BACK
CLOUDY AND COOLER CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 AM WEDNESDAY...WIDESPREAD DENSE FOG HANGING IN THERE
THIS MORNING MOST LOCATIONS. HOWEVER...A FEW OF OUR INLAND SITES
HAVE SEEN VISIBILITIES LIFT TO AROUND A MILE OR TWO...SO IT DOES
LOOK LIKE WE WILL SEE FURTHER GRADUAL IMPROVEMENT THROUGH THE
MORNING HOURS. KEEPING DENSE FOG ADVISORY IN EFFECT THROUGH 10 AM
AS A RESULT. MORNING SOUNDINGS SHOW AN IMPRESSIVE AND WIDESPREAD
SURFACE INVERSION IN A VERY SHALLOW POOL OF COOL AND MOIST AIR.
PREVIOUS DISCUSSION FOLLOWS:
THE COLD FRONT THAT PUSHED SOUTHWARD ACROSS THE AREA LESS THAN 24
HOURS AGO IS STALLED OFFSHORE. THE BOUNDARY IS EASILY DISCERNIBLE
IN 11-3.9 MICRON SATELLITE IMAGERY, LYING APPROXIMATELY 30 MILES
OFFSHORE. (THE FRYING PAN SHOALS BUOY, STILL REPORTING NE WINDS,
IS VERY NEAR THE INFERRED FRONTAL POSITION.) LOW STRATUS AND FOG
COVERS THE AREA WEST OF THE FRONT AND A DENSE FOG ADVISORY HAS
BEEN ISSUED FOR ALL OF OUR COUNTIES THROUGH 10 AM. 00Z MODEL
SOUNDINGS AGREE WITH LAST NIGHT`S 00Z MHX OBSERVED SOUNDING
SHOWING THIS IS A VERY SHALLOW COOL AIRMASS EXTENDING ONLY UP
THROUGH 1500 FEET AGL BEFORE SOUTHWEST WINDS BEGIN ALOFT.
THE FORECAST FOR TODAY IS ONE OF LOW CONFIDENCE DUE TO UNCERTAINTY
IN HOW QUICKLY WE CAN BURN THROUGH THE FOG AND LOW STRATUS. SUN
ANGLES ARE NEARLY AS LOW AS THEY GET SO WE`LL DEPEND JUST AS MUCH
ON MECHANICAL MIXING FROM ABOVE AS DIABATIC HEATING FROM BELOW TO
GET THE CLOUDS OUT. THE 00Z GFS AND ECMWF ERODE THE MESS RATHER
QUICKLY AND THEREFORE SHOW THE POTENTIAL FOR TEMPERATURES IN THE
70S THIS AFTERNOON. OTHER GUIDANCE INCLUDING THE 00Z NAM AND THE
ARW AND NMM VERSIONS OF THE NAM SHOW A SLOWER EROSION OF THE
CLOUDS AND SUBSEQUENTLY COOLER TEMPERATURES TODAY. MY FORECAST
(BASED MOST CLOSELY ON THE 00Z OPERATIONAL AND NMM VERSIONS OF THE
NAM) ERODES CLOUDS EARLY IN THE AFTERNOON WITHIN 20 MILES OF THE
SANTEE RIVER WITH FORECAST HIGHS THERE IN THE LOWER 70S...BUT
HANGS ONTO CLOUDS INTO THE MID AFTERNOON ELSEWHERE WITH HIGHS ONLY
IN THE 60S. QUITE CONCERNING IS THE NEW 08Z RUN OF THE RUC MODEL
WHICH SHOWS TEMPERATURES HOLDING IN THE 50S ACROSS MOST OF THE
AREA THIS AFTERNOON...WITH ANY CLEARING HOLDING OFF UNTIL JUST
BEFORE SUNSET.
THE NEXT SYNOPTIC HIGH CURRENTLY ENTERING THE WESTERN HIGH PLAINS
WILL PUSH A COLD FRONT SOUTHWARD ACROSS THE AREA TONIGHT. WINDS
SHOULD BECOME NORTHEAST AFTER MIDNIGHT. THIS NEW COOL AIRMASS
SHOULD ARRIVE ON NORTHEAST WINDS THAT HAVE PICKED UP ENOUGH
ATLANTIC MOISTURE TO KEEP CLOUDS AGAIN IN PLACE. LOWS SHOULD FALL
TO NEAR 50.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NOT EXPECTING TO MUCH IN THE WAY OF
SUNSHINE THROUGH THE PERIOD. HIGH PRESSURE MOVES EAST JUST NORTH
OF NEW YORK THURSDAY THROUGH FRIDAY WITH A RIDGE AXIS DEVELOPING
INTO THE CAROLINAS. THE RESULTING NE FLOW A THE SURFACE WILL
PROVIDE GENTLE ASCENT VIA UNDERCUTTING TO MAINTAIN AN ALREADY VERY
MOIST LAYER JUST ABOVE THE INVERSION. FCST SOUNDINGS SHOW AMPLE
MOISTURE IN THE 1-4KFT RANGE. SOME HINTING AT THIS MOISTURE MIXING
OUT SOME BY FRIDAY BUT GIVEN THE RELATIVELY NEGLIGIBLE CHANGE IN
THE SYNOPTIC SETUP THIS IS LIKELY IN ERROR. BOTH DAYS LOOK FAIRLY
DREARY WITH SHALLOW MIXING THAT SHOULD CAP HIGH TEMPS TO WITHING A
FEW DEGREES OF 60. ABOVE THE AFOREMENTIONED MOIST LAYER WILL BE A
LAYER THAT IS DRY ENOUGH TO KEEP MEASURABLE PRECIP HARD-PRESSED TO
COME BY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...THE WEDGE PRESENT FOR THE DURATION OF THE
SHORT TERM BREAKS DOWN ON SATURDAY JUST IN TIME FOR A COLD FRONT
TO ARRIVE. DEPENDING ON HOW MUCH DEEP LAYER MOISTURE MANAGES TO
FLOW INTO THE CAROLINAS AHEAD OF THIS BOUNDARY THERE SHOULD BE
SOME REASONABLE INCREASE IN RAINFALL CHANCES. THE AFTERNOON WILL
TURN OUT A BIT WARMER ESPECIALLY IN AREAS THAT MANAGE TO SEE
ENOUGH SUNSHINE. SOON AFTER THE SATURDAY NIGHT FROPA AN ALL-TOO-
FAMILIAR WEDGE SETUP RETURNS BY SUNDAY THAT SHOULD PERSIST INTO
MONDAY IF NOT LONGER. WHILE THIS WILL NOT LEAD TO ANY
SIGNIFICANTLY COOL AIR...MOST PLACES WILL RETURN TO HIGHS JUST SHY
OF 60...IT MAY MEAN A CONTINUATION OF LITTLE SUNSHINE. .SHORT TERM
/THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 AM WEDNESDAY...NOT
EXPECTING TO MUCH IN THE WAY OF SUNSHINE THROUGH THE PERIOD. HIGH
PRESSURE MOVES EAST JUST NORTH OF NEW YORK THURSDAY THROUGH FRIDAY
WITH A RIDGE AXIS DEVELOPING INTO THE CAROLINAS. THE RESULTING NE
FLOW A THE SURFACE WILL PROVIDE GENTLE ASCENT VIA UNDERCUTTING TO
MAINTAIN AN ALREADY VERY MOIST LAYER JUST ABOVE THE INVERSION.
FCST SOUNDINGS SHOW AMPLE MOISTURE IN THE 1-4KFT RANGE. SOME
HINTING AT THIS MOISTURE MIXING OUT SOME BY FRIDAY BUT GIVEN THE
RELATIVELY NEGLIGIBLE CHANGE IN THE SYNOPTIC SETUP THIS IS LIKELY
IN ERROR. BOTH DAYS LOOK FAIRLY DREARY WITH SHALLOW MIXING THAT
SHOULD CAP HIGH TEMPS TO WITHING A FEW DEGREES OF 60. ABOVE THE
AFOREMENTIONED MOIST LAYER WILL BE A LAYER THAT IS DRY ENOUGH TO
KEEP MEASURABLE PRECIP HARD-PRESSED TO COME BY.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z..EVERYONE IS PRETTY MUCH SOCKED IN THIS MORNING WITH
NEAR AIRFIELD MINIMUMS. THIS FOGGY LAYER IS QUITE THIN...WITH THE
VAD WIND PROFILE SHOWING SOUTHEAST WINDS AT 1K FEET. EVEN
SO...WITH THE LOW SUN ANGLE IT WILL TAKE SEVERAL HOURS OF SOLAR
INSOLATION TO MIX THIS STUFF OUT...LIKELY IN THE 15-16Z RANGE. A
VFR AFTERNOON IN STORE AS THE WEDGE RECEDES. THE FOG/STRATUS COULD
RETURN TOWARD THE END OF THE FORECAST PERIOD...LIKELY NOT AS DENSE
AS THIS MORNING.
EXTENDED OUTLOOK...COOL WEDGE OF HIGH PRESSURE WILL BUILD INTO THE
CAROLINAS LATE THU THROUGH FRI...BRINGING ANOTHER ROUND OF
MVFR/IFR STRATUS THROUGH SAT MORNING. MVFR/IFR CIGS MAY DEVELOP
AGAIN ON SUN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 915 AM WEDNESDAY...DENSE FOG ADVISORY CONTINUES OVER THE
WATERS THROUGH 10 AM. FOG IS BEGINNING TO LIFT WELL INLAND...BUT
MAY PERSIST OVER THE WATERS INTO THE EARLY AFTERNOON HOURS AT
LEAST...SO CONSIDERING EXTENDING THE ADVISORY THROUGH THEN. LATEST
OBS SHOW SEAS IN THE 3 FT RANGE IN A VERY LIGHT NORTHERLY WIND.
PREVIOUS DISCUSSION FOLLOWS:
THE COLD FRONT THAT PUSHED SOUTH ACROSS THE AREA YESTERDAY MORNING
IS STALLED 30 MILES OFFSHORE. THE FRYING PAN SHOALS BUOY, STILL
REPORTING NE WINDS, IS VERY NEAR THE INFERRED POSITION OF THE
FRONT. WEST OF THE FRONT INCLUDING OVER THE COASTAL WATERS THIS NE
WIND CONTINUES THIS MORNING WITH LOW CLOUDS AND AREAS OF DENSE
FOG.
THE FORECAST FOR TODAY IS ONE OF FAIRLY LOW CONFIDENCE. HOW
QUICKLY THE COOL WEDGE AIRMASS WEST OF THE FRONT BREAKS DOWN WILL
DETERMINE WHETHER WINDS VEER AROUND TO THE SOUTH TODAY OR REMAIN
NORTHERLY. MY BET IS THE WEDGE WILL BE TENACIOUS AND NOT BREAK
UNTIL FAIRLY LATE IN THE DAY. THIS MEANS A LIGHT NORTHERLY WIND
SHOULD CONTINUE WITHIN 20 MILES OF SHORE. SEA FOG SHOULD BEGIN TO
DISSIPATE LATE IN THE MORNING BUT VISIBILITIES MAY NOT IMPROVE
BEYOND OVER 2-3 MILES UNTIL MID AFTERNOON.
HIGH PRESSURE BUILDING EASTWARD FROM THE PLAINS STATES WILL PUSH
ANOTHER COLD FRONT SOUTH ACROSS THE AREA TONIGHT. THIS WILL LEAD
TO INCREASING NORTH-NORTHEAST WINDS LATE TONIGHT, POSSIBLY
APPROACHING 20 KNOTS BY DAYBREAK THURSDAY.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NORTHERN ZONES MAY BE CLOSE TO ADVISORY
THRESHOLDS AS WEDGE OVER LAND PINCHES GRADIENT JUST ENOUGH FOR
SOME 6 FT SEAS. THE COAST PARALLEL FLOW WILL MAKE FOR A GRADIENT
IN NEARSHORE VS OFFSHORE WAVE HEIGHT AND SO ANY FLUCTUATION IN
WIND DIRECTION COULD PUSH ADVISORY-WORTHY SEAS INTO OR OUT OF THE
FCST ZONES. THE ONLY CHANGE HEADING INTO FRIDAY WILL BE A GRADUAL
EASING OF THE GRADIENT BUT IT MAY BE JUST ENOUGH TO DROP THE
MARGINAL ADVISORY IF ANY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...WINDS ACQUIRE A SOUTHERLY COMPONENT ON
SATURDAY AS THE SHORT TERM WEDGE BREAKS DOWN AND A COLD FRONT
APPROACHES FROM THE WEST. THIS BOUNDARY WILL PUSH THROUGH SATURDAY
NIGHT ALLOWING FOR ANOTHER WEDGE OF HIGH PRESSURE TO SEEP DOWN THE
EAST FACE OF THE APPALACHIANS. NORTH TO NORTHEASTERLY FLOW WILL
RETURN TO THE COASTAL WATERS AND THE GRADIENT MAY RAMP UP
SUFFICIENTLY THAT HEADLINES OR ADVISORY BECOMES NEEDED AGAIN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ017-023-
024-032-033-039-053>056.
NC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR NCZ087-096-
099-105>110.
MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ250-252-
254-256.
&&
$$
SYNOPSIS...MBB
NEAR TERM...REK/TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...DL
MARINE...REK/TRA/MBB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
558 AM EST WED DEC 3 2014
.SYNOPSIS...
HIGH PRESSURE TO OUR NORTH WILL BRING CLOUDY AND COOL WEATHER
THROUGH FRIDAY. AFTER A ONE DAY WARM-UP ON SATURDAY A NEW HIGH WILL
BUILD IN FROM THE NORTH AGAIN ON SUNDAY BRINGING BACK CLOUDY AND
COOLER CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 545 AM WEDNESDAY...THE COLD FRONT THAT PUSHED SOUTHWARD ACROSS
THE AREA LESS THAN 24 HOURS AGO IS STALLED OFFSHORE. THE BOUNDARY
IS EASILY DISCERNIBLE IN 11-3.9 MICRON SATELLITE IMAGERY, LYING
APPROXIMATELY 30 MILES OFFSHORE. (THE FRYING PAN SHOALS BUOY,
STILL REPORTING NE WINDS, IS VERY NEAR THE INFERRED FRONTAL
POSITION.) LOW STRATUS AND FOG COVERS THE AREA WEST OF THE FRONT
AND A DENSE FOG ADVISORY HAS BEEN ISSUED FOR ALL OF OUR COUNTIES
THROUGH 10 AM. 00Z MODEL SOUNDINGS AGREE WITH LAST NIGHT`S 00Z MHX
OBSERVED SOUNDING SHOWING THIS IS A VERY SHALLOW COOL AIRMASS
EXTENDING ONLY UP THROUGH 1500 FEET AGL BEFORE SOUTHWEST WINDS
BEGIN ALOFT.
THE FORECAST FOR TODAY IS ONE OF LOW CONFIDENCE DUE TO UNCERTAINTY
IN HOW QUICKLY WE CAN BURN THROUGH THE FOG AND LOW STRATUS. SUN
ANGLES ARE NEARLY AS LOW AS THEY GET SO WE`LL DEPEND JUST AS MUCH ON
MECHANICAL MIXING FROM ABOVE AS DIABATIC HEATING FROM BELOW TO GET
THE CLOUDS OUT. THE 00Z GFS AND ECMWF ERODE THE MESS RATHER
QUICKLY AND THEREFORE SHOW THE POTENTIAL FOR TEMPERATURES IN THE
70S THIS AFTERNOON. OTHER GUIDANCE INCLUDING THE 00Z NAM AND THE
ARW AND NMM VERSIONS OF THE NAM SHOW A SLOWER EROSION OF THE
CLOUDS AND SUBSEQUENTLY COOLER TEMPERATURES TODAY. MY FORECAST
(BASED MOST CLOSELY ON THE 00Z OPERATIONAL AND NMM VERSIONS OF THE
NAM) ERODES CLOUDS EARLY IN THE AFTERNOON WITHIN 20 MILES OF THE
SANTEE RIVER WITH FORECAST HIGHS THERE IN THE LOWER 70S...BUT
HANGS ONTO CLOUDS INTO THE MID AFTERNOON ELSEWHERE WITH HIGHS ONLY
IN THE 60S. QUITE CONCERNING IS THE NEW 08Z RUN OF THE RUC MODEL
WHICH SHOWS TEMPERATURES HOLDING IN THE 50S ACROSS MOST OF THE
AREA THIS AFTERNOON...WITH ANY CLEARING HOLDING OFF UNTIL JUST
BEFORE SUNSET.
THE NEXT SYNOPTIC HIGH CURRENTLY ENTERING THE WESTERN HIGH PLAINS
WILL PUSH A COLD FRONT SOUTHWARD ACROSS THE AREA TONIGHT. WINDS
SHOULD BECOME NORTHEAST AFTER MIDNIGHT. THIS NEW COOL AIRMASS SHOULD
ARRIVE ON NORTHEAST WINDS THAT HAVE PICKED UP ENOUGH ATLANTIC
MOISTURE TO KEEP CLOUDS AGAIN IN PLACE. LOWS SHOULD FALL TO NEAR 50.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NOT EXPECTING TO MUCH IN THE WAY OF SUNSHINE
THROUGH THE PERIOD. HIGH PRESSURE MOVES EAST JUST NORTH OF NEW YORK
THURSDAY THROUGH FRIDAY WITH A RIDGE AXIS DEVELOPING INTO THE
CAROLINAS. THE RESULTING NE FLOW A THE SURFACE WILL PROVIDE GENTLE
ASCENT VIA UNDERCUTTING TO MAINTAIN AN ALREADY VERY MOIST LAYER JUST
ABOVE THE INVERSION. FCST SOUNDINGS SHOW AMPLE MOISTURE IN THE
1-4KFT RANGE. SOME HINTING AT THIS MOISTURE MIXING OUT SOME BY
FRIDAY BUT GIVEN THE RELATIVELY NEGLIGIBLE CHANGE IN THE SYNOPTIC
SETUP THIS IS LIKELY IN ERROR. BOTH DAYS LOOK FAIRLY DREARY WITH
SHALLOW MIXING THAT SHOULD CAP HIGH TEMPS TO WITHING A FEW DEGREES
OF 60. ABOVE THE AFOREMENTIONED MOIST LAYER WILL BE A LAYER THAT IS
DRY ENOUGH TO KEEP MEASURABLE PRECIP HARD-PRESSED TO COME BY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...THE WEDGE PRESENT FOR THE DURATION OF THE
SHORT TERM BREAKS DOWN ON SATURDAY JUST IN TIME FOR A COLD FRONT TO
ARRIVE. DEPENDING ON HOW MUCH DEEP LAYER MOISTURE MANAGES TO FLOW
INTO THE CAROLINAS AHEAD OF THIS BOUNDARY THERE SHOULD BE SOME
REASONABLE INCREASE IN RAINFALL CHANCES. THE AFTERNOON WILL TURN OUT
A BIT WARMER ESPECIALLY IN AREAS THAT MANAGE TO SEE ENOUGH SUNSHINE.
SOON AFTER THE SATURDAY NIGHT FROPA AN ALL-TOO-FAMILIAR WEDGE SETUP
RETURNS BY SUNDAY THAT SHOULD PERSIST INTO MONDAY IF NOT LONGER.
WHILE THIS WILL NOT LEAD TO ANY SIGNIFICANTLY COOL AIR...MOST PLACES
WILL RETURN TO HIGHS JUST SHY OF 60...IT MAY MEAN A CONTINUATION OF
LITTLE SUNSHINE. .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NOT EXPECTING TO MUCH IN THE WAY OF SUNSHINE
THROUGH THE PERIOD. HIGH PRESSURE MOVES EAST JUST NORTH OF NEW YORK
THURSDAY THROUGH FRIDAY WITH A RIDGE AXIS DEVELOPING INTO THE
CAROLINAS. THE RESULTING NE FLOW A THE SURFACE WILL PROVIDE GENTLE
ASCENT VIA UNDERCUTTING TO MAINTAIN AN ALREADY VERY MOIST LAYER JUST
ABOVE THE INVERSION. FCST SOUNDINGS SHOW AMPLE MOISTURE IN THE
1-4KFT RANGE. SOME HINTING AT THIS MOISTURE MIXING OUT SOME BY
FRIDAY BUT GIVEN THE RELATIVELY NEGLIGIBLE CHANGE IN THE SYNOPTIC
SETUP THIS IS LIKELY IN ERROR. BOTH DAYS LOOK FAIRLY DREARY WITH
SHALLOW MIXING THAT SHOULD CAP HIGH TEMPS TO WITHING A FEW DEGREES
OF 60. ABOVE THE AFOREMENTIONED MOIST LAYER WILL BE A LAYER THAT IS
DRY ENOUGH TO KEEP MEASURABLE PRECIP HARD-PRESSED TO COME BY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z..EVERYONE IS PRETTY MUCH SOCKED IN THIS MORNING WITH NEAR
AIRFIELD MINIMUMS. THIS FOGGY LAYER IS QUITE THIN...WITH THE VAD
WIND PROFILE SHOWING SOUTHEAST WINDS AT 1K FEET. EVEN SO...WITH THE
LOW SUN ANGLE IT WILL TAKE SEVERAL HOURS OF SOLAR INSOLATION TO MIX
THIS STUFF OUT...LIKELY IN THE 15-16Z RANGE. A VFR AFTERNOON IN
STORE AS THE WEDGE RECEDES. THE FOG/STRATUS COULD RETURN TOWARD THE
END OF THE FORECAST PERIOD...LIKELY NOT AS DENSE AS THIS MORNING.
EXTENDED OUTLOOK...COOL WEDGE OF HIGH PRESSURE WILL BUILD INTO THE
CAROLINAS LATE THU THROUGH FRI...BRINGING ANOTHER ROUND OF MVFR/IFR
STRATUS THROUGH SAT MORNING. MVFR/IFR CIGS MAY DEVELOP AGAIN ON SUN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 545 AM WEDNESDAY...THE COLD FRONT THAT PUSHED SOUTH ACROSS THE
AREA YESTERDAY MORNING IS STALLED 30 MILES OFFSHORE. THE FRYING
PAN SHOALS BUOY, STILL REPORTING NE WINDS, IS VERY NEAR THE INFERRED
POSITION OF THE FRONT. WEST OF THE FRONT INCLUDING OVER THE
COASTAL WATERS THIS NE WIND CONTINUES THIS MORNING WITH LOW CLOUDS
AND AREAS OF DENSE FOG.
THE FORECAST FOR TODAY IS ONE OF FAIRLY LOW CONFIDENCE. HOW QUICKLY
THE COOL WEDGE AIRMASS WEST OF THE FRONT BREAKS DOWN WILL DETERMINE
WHETHER WINDS VEER AROUND TO THE SOUTH TODAY OR REMAIN NORTHERLY. MY
BET IS THE WEDGE WILL BE TENACIOUS AND NOT BREAK UNTIL FAIRLY LATE
IN THE DAY. THIS MEANS A LIGHT NORTHERLY WIND SHOULD CONTINUE WITHIN
20 MILES OF SHORE. SEA FOG SHOULD BEGIN TO DISSIPATE LATE IN THE
MORNING BUT VISIBILITIES MAY NOT IMPROVE BEYOND OVER 2-3 MILES UNTIL
MID AFTERNOON.
HIGH PRESSURE BUILDING EASTWARD FROM THE PLAINS STATES WILL PUSH
ANOTHER COLD FRONT SOUTH ACROSS THE AREA TONIGHT. THIS WILL LEAD TO
INCREASING NORTH-NORTHEAST WINDS LATE TONIGHT, POSSIBLY APPROACHING
20 KNOTS BY DAYBREAK THURSDAY.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NORTHERN ZONES MAY BE CLOSE TO ADVISORY
THRESHOLDS AS WEDGE OVER LAND PINCHES GRADIENT JUST ENOUGH FOR SOME
6 FT SEAS. THE COAST PARALLEL FLOW WILL MAKE FOR A GRADIENT IN
NEARSHORE VS OFFSHORE WAVE HEIGHT AND SO ANY FLUCTUATION IN WIND
DIRECTION COULD PUSH ADVISORY-WORTHY SEAS INTO OR OUT OF THE FCST
ZONES. THE ONLY CHANGE HEADING INTO FRIDAY WILL BE A GRADUAL EASING
OF THE GRADIENT BUT IT MAY BE JUST ENOUGH TO DROP THE MARGINAL
ADVISORY IF ANY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...WINDS ACQUIRE A SOUTHERLY COMPONENT ON
SATURDAY AS THE SHORT TERM WEDGE BREAKS DOWN AND A COLD FRONT
APPROACHES FROM THE WEST. THIS BOUNDARY WILL PUSH THROUGH SATURDAY
NIGHT ALLOWING FOR ANOTHER WEDGE OF HIGH PRESSURE TO SEEP DOWN THE
EAST FACE OF THE APPALACHIANS. NORTH TO NORTHEASTERLY FLOW WILL
RETURN TO THE COASTAL WATERS AND THE GRADIENT MAY RAMP UP
SUFFICIENTLY THAT HEADLINES OR ADVISORY BECOMES NEEDED AGAIN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ017-023-
024-032-033-039-053>056.
NC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR NCZ087-096-
099-105>110.
MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ250-252-
254-256.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
544 AM EST WED DEC 3 2014
.SYNOPSIS...
HIGH PRESSURE TO OUR NORTH WILL BRING CLOUDY AND COOL WEATHER
THROUGH FRIDAY. AFTER A ONE DAY WARM-UP ON SATURDAY A NEW HIGH WILL
BUILD IN FROM THE NORTH AGAIN ON SUNDAY BRINGING BACK CLOUDY AND
COOLER CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 545 AM WEDNESDAY...THE COLD FRONT THAT PUSHED SOUTHWARD ACROSS
THE AREA LESS THAN 24 HOURS AGO IS STALLED OFFSHORE. THE BOUNDARY
IS EASILY DISCERNIBLE IN 11-3.9 MICRON SATELLITE IMAGERY, LYING
APPROXIMATELY 30 MILES OFFSHORE. (THE FRYING PAN SHOALS BUOY,
STILL REPORTING NE WINDS, IS VERY NEAR THE INFERRED FRONTAL
POSITION.) LOW STRATUS AND FOG COVERS THE AREA WEST OF THE FRONT
AND A DENSE FOG ADVISORY HAS BEEN ISSUED FOR ALL OF OUR COUNTIES
THROUGH 10 AM. 00Z MODEL SOUNDINGS AGREE WITH LAST NIGHT`S 00Z MHX
OBSERVED SOUNDING SHOWING THIS IS A VERY SHALLOW COOL AIRMASS
EXTENDING ONLY UP THROUGH 1500 FEET AGL BEFORE SOUTHWEST WINDS
BEGIN ALOFT.
THE FORECAST FOR TODAY IS ONE OF LOW CONFIDENCE DUE TO UNCERTAINTY
IN HOW QUICKLY WE CAN BURN THROUGH THE FOG AND LOW STRATUS. SUN
ANGLES ARE NEARLY AS LOW AS THEY GET SO WE`LL DEPEND JUST AS MUCH ON
MECHANICAL MIXING FROM ABOVE AS DIABATIC HEATING FROM BELOW TO GET
THE CLOUDS OUT. THE 00Z GFS AND ECMWF ERODE THE MESS RATHER
QUICKLY AND THEREFORE SHOW THE POTENTIAL FOR TEMPERATURES IN THE
70S THIS AFTERNOON. OTHER GUIDANCE INCLUDING THE 00Z NAM AND THE
ARW AND NMM VERSIONS OF THE NAM SHOW A SLOWER EROSION OF THE
CLOUDS AND SUBSEQUENTLY COOLER TEMPERATURES TODAY. MY FORECAST
(BASED MOST CLOSELY ON THE 00Z OPERATIONAL AND NMM VERSIONS OF THE
NAM) ERODES CLOUDS EARLY IN THE AFTERNOON WITHIN 20 MILES OF THE
SANTEE RIVER WITH FORECAST HIGHS THERE IN THE LOWER 70S...BUT
HANGS ONTO CLOUDS INTO THE MID AFTERNOON ELSEWHERE WITH HIGHS ONLY
IN THE 60S. QUITE CONCERNING IS THE NEW 08Z RUN OF THE RUC MODEL
WHICH SHOWS TEMPERATURES HOLDING IN THE 50S ACROSS MOST OF THE
AREA THIS AFTERNOON...WITH ANY CLEARING HOLDING OFF UNTIL JUST
BEFORE SUNSET.
THE NEXT SYNOPTIC HIGH CURRENTLY ENTERING THE WESTERN HIGH PLAINS
WILL PUSH A COLD FRONT SOUTHWARD ACROSS THE AREA TONIGHT. WINDS
SHOULD BECOME NORTHEAST AFTER MIDNIGHT. THIS NEW COOL AIRMASS SHOULD
ARRIVE ON NORTHEAST WINDS THAT HAVE PICKED UP ENOUGH ATLANTIC
MOISTURE TO KEEP CLOUDS AGAIN IN PLACE. LOWS SHOULD FALL TO NEAR 50.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NOT EXPECTING TO MUCH IN THE WAY OF SUNSHINE
THROUGH THE PERIOD. HIGH PRESSURE MOVES EAST JUST NORTH OF NEW YORK
THURSDAY THROUGH FRIDAY WITH A RIDGE AXIS DEVELOPING INTO THE
CAROLINAS. THE RESULTING NE FLOW A THE SURFACE WILL PROVIDE GENTLE
ASCENT VIA UNDERCUTTING TO MAINTAIN AN ALREADY VERY MOIST LAYER JUST
ABOVE THE INVERSION. FCST SOUNDINGS SHOW AMPLE MOISTURE IN THE
1-4KFT RANGE. SOME HINTING AT THIS MOISTURE MIXING OUT SOME BY
FRIDAY BUT GIVEN THE RELATIVELY NEGLIGIBLE CHANGE IN THE SYNOPTIC
SETUP THIS IS LIKELY IN ERROR. BOTH DAYS LOOK FAIRLY DREARY WITH
SHALLOW MIXING THAT SHOULD CAP HIGH TEMPS TO WITHING A FEW DEGREES
OF 60. ABOVE THE AFOREMENTIONED MOIST LAYER WILL BE A LAYER THAT IS
DRY ENOUGH TO KEEP MEASURABLE PRECIP HARD-PRESSED TO COME BY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...THE WEDGE PRESENT FOR THE DURATION OF THE
SHORT TERM BREAKS DOWN ON SATURDAY JUST IN TIME FOR A COLD FRONT TO
ARRIVE. DEPENDING ON HOW MUCH DEEP LAYER MOISTURE MANAGES TO FLOW
INTO THE CAROLINAS AHEAD OF THIS BOUNDARY THERE SHOULD BE SOME
REASONABLE INCREASE IN RAINFALL CHANCES. THE AFTERNOON WILL TURN OUT
A BIT WARMER ESPECIALLY IN AREAS THAT MANAGE TO SEE ENOUGH SUNSHINE.
SOON AFTER THE SATURDAY NIGHT FROPA AN ALL-TOO-FAMILIAR WEDGE SETUP
RETURNS BY SUNDAY THAT SHOULD PERSIST INTO MONDAY IF NOT LONGER.
WHILE THIS WILL NOT LEAD TO ANY SIGNIFICANTLY COOL AIR...MOST PLACES
WILL RETURN TO HIGHS JUST SHY OF 60...IT MAY MEAN A CONTINUATION OF
LITTLE SUNSHINE. .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NOT EXPECTING TO MUCH IN THE WAY OF SUNSHINE
THROUGH THE PERIOD. HIGH PRESSURE MOVES EAST JUST NORTH OF NEW YORK
THURSDAY THROUGH FRIDAY WITH A RIDGE AXIS DEVELOPING INTO THE
CAROLINAS. THE RESULTING NE FLOW A THE SURFACE WILL PROVIDE GENTLE
ASCENT VIA UNDERCUTTING TO MAINTAIN AN ALREADY VERY MOIST LAYER JUST
ABOVE THE INVERSION. FCST SOUNDINGS SHOW AMPLE MOISTURE IN THE
1-4KFT RANGE. SOME HINTING AT THIS MOISTURE MIXING OUT SOME BY
FRIDAY BUT GIVEN THE RELATIVELY NEGLIGIBLE CHANGE IN THE SYNOPTIC
SETUP THIS IS LIKELY IN ERROR. BOTH DAYS LOOK FAIRLY DREARY WITH
SHALLOW MIXING THAT SHOULD CAP HIGH TEMPS TO WITHING A FEW DEGREES
OF 60. ABOVE THE AFOREMENTIONED MOIST LAYER WILL BE A LAYER THAT IS
DRY ENOUGH TO KEEP MEASURABLE PRECIP HARD-PRESSED TO COME BY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z..LIFR CONDITIONS ARE BECOMING WIDESPREAD IN LOW STRATUS
AND FOG. WORST CONDITIONS EXPECTED ALONG THE COAST WHERE VLIFR
SHOULD DEVELOP, PARTICULARLY AT THE ILM AIRPORT. AFTER
DAYBREAK...ANTICIPATE CONDITIONS TO GRADUALLY IMPROVE TO MVFR BY
LATE MORNING.
EXTENDED OUTLOOK...COOL WEDGE OF HIGH PRESSURE WILL BUILD INTO THE
CAROLINAS LATE THU THROUGH FRI...BRINGING ANOTHER ROUND OF MVFR/IFR
STRATUS THROUGH SAT MORNING. MVFR/IFR CIGS MAY DEVELOP AGAIN ON SUN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 545 AM WEDNESDAY...THE COLD FRONT THAT PUSHED SOUTH ACROSS THE
AREA YESTERDAY MORNING IS STALLED 30 MILES OFFSHORE. THE FRYING
PAN SHOALS BUOY, STILL REPORTING NE WINDS, IS VERY NEAR THE INFERRED
POSITION OF THE FRONT. WEST OF THE FRONT INCLUDING OVER THE
COASTAL WATERS THIS NE WIND CONTINUES THIS MORNING WITH LOW CLOUDS
AND AREAS OF DENSE FOG.
THE FORECAST FOR TODAY IS ONE OF FAIRLY LOW CONFIDENCE. HOW QUICKLY
THE COOL WEDGE AIRMASS WEST OF THE FRONT BREAKS DOWN WILL DETERMINE
WHETHER WINDS VEER AROUND TO THE SOUTH TODAY OR REMAIN NORTHERLY. MY
BET IS THE WEDGE WILL BE TENACIOUS AND NOT BREAK UNTIL FAIRLY LATE
IN THE DAY. THIS MEANS A LIGHT NORTHERLY WIND SHOULD CONTINUE WITHIN
20 MILES OF SHORE. SEA FOG SHOULD BEGIN TO DISSIPATE LATE IN THE
MORNING BUT VISIBILITIES MAY NOT IMPROVE BEYOND OVER 2-3 MILES UNTIL
MID AFTERNOON.
HIGH PRESSURE BUILDING EASTWARD FROM THE PLAINS STATES WILL PUSH
ANOTHER COLD FRONT SOUTH ACROSS THE AREA TONIGHT. THIS WILL LEAD TO
INCREASING NORTH-NORTHEAST WINDS LATE TONIGHT, POSSIBLY APPROACHING
20 KNOTS BY DAYBREAK THURSDAY.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NORTHERN ZONES MAY BE CLOSE TO ADVISORY
THRESHOLDS AS WEDGE OVER LAND PINCHES GRADIENT JUST ENOUGH FOR SOME
6 FT SEAS. THE COAST PARALLEL FLOW WILL MAKE FOR A GRADIENT IN
NEARSHORE VS OFFSHORE WAVE HEIGHT AND SO ANY FLUCTUATION IN WIND
DIRECTION COULD PUSH ADVISORY-WORTHY SEAS INTO OR OUT OF THE FCST
ZONES. THE ONLY CHANGE HEADING INTO FRIDAY WILL BE A GRADUAL EASING
OF THE GRADIENT BUT IT MAY BE JUST ENOUGH TO DROP THE MARGINAL
ADVISORY IF ANY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...WINDS ACQUIRE A SOUTHERLY COMPONENT ON
SATURDAY AS THE SHORT TERM WEDGE BREAKS DOWN AND A COLD FRONT
APPROACHES FROM THE WEST. THIS BOUNDARY WILL PUSH THROUGH SATURDAY
NIGHT ALLOWING FOR ANOTHER WEDGE OF HIGH PRESSURE TO SEEP DOWN THE
EAST FACE OF THE APPALACHIANS. NORTH TO NORTHEASTERLY FLOW WILL
RETURN TO THE COASTAL WATERS AND THE GRADIENT MAY RAMP UP
SUFFICIENTLY THAT HEADLINES OR ADVISORY BECOMES NEEDED AGAIN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ017-023-
024-032-033-039-053>056.
NC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR NCZ087-096-
099-105>110.
MARINE...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ250-252-
254-256.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...TRA/SGL
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
549 AM CST WED DEC 3 2014
.AVIATION...
SUB-TROPICAL HIGH CLOUD SHIELD SHOULD CONTINUE THROUGH MUCH OF THE
COMING 24 HOURS. WEAK COLD FRONT WILL SHIFT SOUTHWARD MID TO LATE
MORNING WITH AN MVFR CLOUD LAYER EXPECTED TO DEVELOP AT KCDS BY
EARLY THIS EVENING AND PERSIST WELL INTO OR THROUGH THE NIGHT.
ALSO POSSIBLE FOR AT LEAST MVFR VISIBILITY RESTRICTIONS TO DEVELOP
AT KCDS MAINLY LATER TODAY OR TONIGHT WITH LESSER CHANCES AT BOTH
KPVW AND KLBB LATER TONIGHT AS WELL. WE HAVE REMOVED THE PREVIOUS
TEMPO AT KCDS FOR LIGHT VISIBILITY RESTRICTIONS LASTING UNTIL 14Z
THIS MORNING AS DEW-POINT DEPRESSIONS HAVE NOT SIGNIFICANTLY
CLOSED WHILE THE HRRR TRENDS HAVE BACKED OFF GRADUALLY ON AREAL
COVERAGE OF REDUCED VISIBILITY THIS MORNING. WE WILL CONTINUE TO
REASSESS VISIBILITY ISSUES FOR LATER FORECASTS. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 358 AM CST WED DEC 3 2014/
SHORT TERM...
A FLAT UPPER RIDGE WILL GRADUALLY MOVE OVERHEAD TODAY AND OFF TO THE
EAST ON THURSDAY WITH AN ABUNDANT SUBTROPICAL MOISTURE PLUME IN THE
MID AND UPPER LEVELS THIS MORNING...PERHAPS THINNING OR CLEARING
BRIEFLY AT TIMES TODAY...BEFORE THICKENING AGAIN TONIGHT. A MODEST
MOUNTAIN WAVE APPEARS LIKELY TO REMAIN A PLAYER IN HIGH CLOUD
COVER THOUGH MAY WEAKEN OR RELEASE BRIEFLY BEHIND A PASSING WAVE
LATER THIS MORNING. AT THE SURFACE...WE EXPECT A WEAKENING COLD
FRONT TO SAG THROUGH THE AREA LATER THIS MORNING BRINGING A 180
DEGREE WIND SHIFT. HIGHER DEW-POINTS SURGING NORTH THROUGH THE
ROLLING PLAINS MAY LEAD TO PATCHY FOG THIS MORNING...AND WE EXPECT
MOISTENING TO WORK UP ONTO THE CAPROCK AS WELL BY LATER TODAY. WE
HAVE ADDED A MENTION OF PATCHY FOG TONIGHT AND EXPANDED A BIT ONTO
THE CAPROCK. PRIOR TO PASSAGE OF THE COLD FRONT...THERE MAY BE
ENOUGH DOWNSLOPE COMPONENT THROUGH MID MORNING FOR A QUICK WARM-UP
ACROSS SOUTHERN COUNTIES DEPENDING ON IF HIGH CLOUDS THIN OR NOT.
TEMPERATURE GUIDANCE TODAY HAS BOUNCED AROUND CONSIDERABLY AS
SOLUTIONS HAVE STRUGGLED TO LATCH ONTO ABOVE FEATURES...THOUGH WE
HAVE SOME FAVORITISM TOWARDS THE LATEST TRENDS BEING WARMER THAN
PREVIOUS. IN SPITE OF RELATIVELY LOW CONFIDENCE WITH SEVERAL
SENSIBLE ELEMENTS TODAY...WE EXPECT BENIGN CONDITIONS TO DOMINATE
OVER-ALL. RMCQUEEN
LONG TERM...
A PROGRESSIVE SOUTHERN STREAM WILL BRING MULTIPLE CHANCES FOR
SHOWERS THROUGH THE NEXT SEVEN DAYS...ALBEIT NONE OF THEM APPEARING
TO BE TERRIBLY IMPRESSIVE AT THIS JUNCTURE...WHILE MAINTAINING A
FAIRLY STEADY STATE AIRMASS ACROSS THE REGION.
THE FIRST OF THESE DISTURBANCES IS SET TO SLIDE ACROSS THE TEXAS AND
OKLAHOMA PANHANDLES THURSDAY EVENING. THE LATEST TRENDS HAVE
CONTINUED TO SUGGEST A DAMPENING OF THIS IMPULSE...BUT MOISTURE
RETURN WILL BE UNDERWAY BY THURSDAY MORNING...WITH NORTHBOUND MOVING
STRATUS AND PATCHY FOG...AS TOP-DOWN MOISTENING TAKES PLACE
DOWNSTREAM OF THE APPROACHING SYSTEM. HOWEVER...A DRY POCKET BELOW
ABOUT H70 MAY PROVE TO BE A MITIGATING FACTOR IN PRECIPITATION
REACHING THE GROUND...THUS ALLOWING FOR ONLY VIRGA SHOWERS. WILL
CONTINUE TO MONITOR THE STRENGTH OF THIS SYSTEM AS IT HEADS ASHORE
THE PACIFIC COAST TONIGHT...BUT FEEL SLIGHT CHANCE POPS ARE STILL
WARRANTED NEAR THE NEW MEXICO STATE LINE BY LATE THURSDAY AFTERNOON
SPREADING EAST THURSDAY EVENING/EARLY NIGHT WITH INCREASING
MOISTURE/OMEGA PROFILES.
INCREASING HEIGHTS AND DOWNSLOPE WINDS SHOULD LEAD TO A NOTICEABLE
WARMUP WELL INTO THE 60S FRIDAY DESPITE A WEAK FRONT/NORTHERLY WIND
SHIFT SET TO MOVE THROUGH WEST TEXAS. THIS FRONT WILL HALT THE
WARMUP...SENDING TEMPERATURES BACK DOWN CLOSER TO AVERAGE IN THE
MID-UPPER 50S BEGINNING SATURDAY AND LASTING INTO NEXT WEEK. AT THE
SAME TIME...THE NEXT UPPER TROUGH WILL ENTER THE DESERT SOUTHWEST
AND BRING A RETURN TO CYCLONIC FLOW SATURDAY AFTERNOON. THIS SYSTEM
TOO HAS CONSISTENTLY SHOWN A WEAKENING TREND...NOW EXHIBITING A
POSITIVE TILT AND PERHAPS SUGGESTING THE BEST CHANCES FOR RAIN TO
RESIDE ACROSS THE SOUTHERN SOUTH PLAINS INTO THE SOUTHERN ROLLING
PLAINS SATURDAY EVENING INTO SUNDAY. EXACTLY HOW FAR SOUTH FRIDAY/S
FRONT PUSHES SOUTH MAY BE A LARGE DETERMINING FACTOR IN LOCAL
PRECIPITATION CHANCES AS THIS WILL AFFECT THE DEGREE/SPEED OF RETURN
FLOW AND GULF MOISTURE.
MONDAY LOOKS TO BRING ANOTHER DRY FRONTAL PASSAGE WITH UPPER RIDGING
IN VICINITY OF THE REGION AND ANOTHER POTENTIALLY LOOMING TROUGH
DEVELOPING UPSTREAM. HAVE KEPT LOW END POPS IN PLACE FOR MONDAY
EVENING INTO TUESDAY AT THIS TIME...BUT SIMILAR CONCERNS TO THE
WEEKEND/S SYSTEM MAY COME TO FRUITION WITH THE ECMWF NOW SHOWING
THIS SYSTEM DEVELOPING AND TRACKING MUCH FARTHER TO OUR SOUTH AND
WEST BEHIND AN IMPRESSIVE EASTERN CONUS UPPER LOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 51 35 61 39 62 / 0 0 20 20 10
TULIA 51 32 60 42 62 / 0 10 20 20 10
PLAINVIEW 54 35 59 42 64 / 0 0 10 20 10
LEVELLAND 60 36 59 43 67 / 0 0 10 20 10
LUBBOCK 58 35 60 45 67 / 0 0 10 20 10
DENVER CITY 65 38 61 43 69 / 0 0 10 20 10
BROWNFIELD 62 36 60 44 68 / 0 0 10 20 10
CHILDRESS 51 36 60 47 67 / 0 10 10 20 10
SPUR 61 35 59 47 69 / 0 0 10 20 10
ASPERMONT 61 39 62 51 71 / 0 10 10 20 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
1044 AM PST WED DEC 3 2014
.UPDATE...
UPDATED TO LOWER POP OUT IN THE BASIN AND RANGE AND FOR MONO
COUNTY (ESPECIALLY FROM HIGHWAY 395 EAST) THROUGH THIS EVENING.
I ALSO ADJUSTED THE WORDING FOR THE WINTER STORM WARNING FOR THE
LAKE TAHOE AREA TO MENTION THAT PASSES BELOW 8000 FEET WILL LIKELY
REMAIN JUST WET THROUGH SUNSET DUE TO ABOVE FREEZING ROAD
TEMPERATURES. THIS EVENING, ISSUES MAY RETURN FOR I-80 AND HIGHWAY
50 OVER THE CREST AS THE HRRR IS SHOWING ANOTHER HEAVY BAND OF
SNOW SHOWERS ARRIVING THIS EVENING. SNYDER
&&
.SYNOPSIS...
A MILD WINTER STORM WILL CONTINUE TO BRING RAIN AND HIGH ELEVATION
SNOW THROUGH TONIGHT WITH PERIODS OF SLICK CONDITIONS OVER HIGHER
SIERRA PASSES. A WEAKER STORM WILL BRING SOME LIGHT PRECIPITATION
FRIDAY NIGHT WITH EXTENSIVE CLOUDS. OTHERWISE IT WILL BE DRIER
THROUGH THE WEEKEND WITH MILD TEMPERATURES.
&&
.PREVIOUS DISCUSSION... /ISSUED 239 AM PST WED DEC 3 2014/
SHORT TERM...
MAIN UPPER LOW WAS BEGINNING TO LIFT OUT THIS MORNING WITH QUITE A
BIT OF LIGHTNING NOTED WITH HEAVIER CONVECTIVE BANDS ACROSS
NORTHERN CA. SUBSIDENCE AHEAD OF SYSTEM OVER THE EASTERN SIERRA
AND WESTERN NV WAS RESULTING IN AN UNUSUAL MIX OF SHOWERS AND FOG
WITH OCCASIONAL BREAKS IN THE CLOUDS. ANOTHER THING OF NOTE THIS
MORNING WERE THE WINDS OVER THE TAHOE BASIN AND NORTHEAST CA.
OCCASIONAL GUSTS TO 20-25 MPH WERE OBSERVED WHICH IS A SIGN THAT
THE LOWER ATMOSPHERE IS BEGINNING TO MIX OUT. KTVL JUMPED INTO THE
LOWER 40S WITH MORE SITES OBSERVING RAIN RATHER THAN SNOW, EVEN AT
TEMPS CLOSE TO OR JUST ABOVE FREEZING.
MODELS CONTINUE TO FOCUS HEAVIEST QPF OVER NORTH CENTRAL CA TODAY
AND WE HAVE BUMPED UP NUMBERS FOR SIERRA, PLUMAS AND LASSEN
COUNTIES. THESE AREAS COULD RECEIVE ANOTHER 1-1.5 INCHES OF QPF
THROUGH THIS EVENING. THE TAHOE BASIN WILL BE RIGHT ON THE
SOUTHERN EDGE OF BEST UPPER FORCING, BUT A VERY MOIST ENVIRONMENT
WILL BE AVAILABLE FOR SEVERAL ROUNDS OF MODERATE TO HEAVY RAIN AND
HIGH ELEVATION SNOWFALL. SNOW LEVELS WERE MAINTAINED AT 7000-7500
FEET NOW THAT THE ATMOSPHERE IS MIXING. SNOW LEVELS COULD BRIEFLY
FALL BELOW 7000 FEET, BUT SNOW AND SLUSH ACCUMULATIONS WILL BE
CONFINED TO AREAS ABOVE 7000 FEET WITH THE WORST CONDITIONS AT THE
HIGHEST PASSES INCLUDING CARSON PASS AND MT ROSE SUMMIT. THE
WINTER STORM WARNING WILL REMAIN IN EFFECT ABOVE 7000 FEET WHERE
ANOTHER FOOT OR SO OF SNOW IS POSSIBLE, ESPECIALLY WEST OF HIGHWAY
89. THE ATMOSPHERE WILL BE UNSTABLE ENOUGH FOR SPILLOVER INTO
WESTERN NV, WITH THE BEST POTENTIAL NORTH OF I-80 WHERE WE BUMPED
POPS AND QPF UP SIGNIFICANTLY TODAY. THE BIG QUESTION WILL BE
WHETHER OR NOT THE RENO-CARSON CITY AREA WILL BE IN THIS BAND AS
SOME MODELS KEEP IT JUST NORTH. HIGH POPS WILL BE MAINTAINED AS
SATELLITE AND RADAR TRAJECTORY OF NEXT WAVE BRINGS ITS SOUTHERN
EDGE ACROSS THE SIERRA FRONT.
RAIN AND SNOW WILL BEGIN TO TAPER TONIGHT AND THURSDAY ALTHOUGH A
MOIST WESTERLY FLOW WILL PERSIST AND BRING THE POTENTIAL FOR
SHOWERS, ESPECIALLY ALONG THE SIERRA AND NORTHEAST CA. WHERE
PARTIAL CLEARING OCCURS TONIGHT, THERE COULD BE ANOTHER ROUND OF
FOG, ESPECIALLY SOUTH OF I-80. THERE SHOULD BE A LULL IN THE
SHOWERS THURSDAY NIGHT AND EARLY FRIDAY ALTHOUGH CLOUDS WILL BE ON
THE INCREASE AS A WEAKER SYSTEM APPROACHES. THAT SYSTEM WILL BRING
A CHANCE OF SHOWERS FOR THE SIERRA AND AREAS NORTH OF I-80 FRI
AFTN/FRI NGT. HOHMANN
LONG TERM...SATURDAY THROUGH TUESDAY...
MODELS ARE IN BETTER AGREEMENT THIS MORNING WITH THE FRIDAY NIGHT
SYSTEM WINDING DOWN SATURDAY. THIS WAVE WILL KEEP SOME THREAT OF
PRECIP NORTH OF A SOUTH LAKE TO GERLACH LINE AS IT WEAKENS INTO
THE MEAN RIDGE. THAT RIDGE WILL HOLD INTO SUNDAY AS IT SLOWLY
MOVES EAST TOWARD THE CONTINENTAL DIVIDE. EXPECT A GENERALLY DRY
DAY SUNDAY AS A RESULT.
FOR EARLY NEXT WEEK, THE MODELS ARE IN GOOD GENERAL AGREEMENT WITH
THE OVERALL PATTERN. THE MEAN RIDGE WILL SET UP NEAR THE
CONTINENTAL DIVIDE WITH A GENERAL WSW FLOW ACROSS THE SIERRA AND
WESTERN NEVADA. THERE ARE DIFFERENCES IN THE DETAILS OF THE TRACK
OF THE INDIVIDUAL SHORT WAVES EMBEDDED IN THE FLOW, HOWEVER. THE
EC IS GENERALLY FURTHER NORTH WHILE THE GFS IS A BIT FURTHER SOUTH
AND QUITE A BIT WETTER. THEIR ENSEMBLE MEANS GENERALLY SUPPORT
THEIR RESPECTIVE DETERMINISTIC RUNS.
FOR NOW, INCREASED THE THREAT OF PRECIP A BIT, WITH THE GREATEST
CHANCE NORTH OF A SUSANVILLE TO GERLACH LINE. THIS IDEA LEANS MORE
TOWARD THE EC BECAUSE I HAVE A HARD TIME SEEING THESE INITIAL
WAVES BRINGING THAT MUCH MOISTURE THIS FAR SOUTH WHEN THE JET
STREAM IS DIRECTED INTO WASHINGTON. IT REMAINS POSSIBLE SO WE WILL
NEED TO WATCH IT IN THE COMING DAYS. TEMPERATURES WILL CONTINUE TO
AVERAGE A FEW DEGREES ABOVE NORMAL THROUGH THE PERIOD. WALLMANN
AVIATION...
MODERATE TO HIGH CONFIDENCE IN GENERAL IFR/MVFR CONDITIONS CONTINUING
ACROSS THE SIERRA AND WESTERN NEVADA NORTH AND WEST OF A KMMH TO
KYER TO KLOL LINE. THESE CONDITIONS WILL BE BELOW AIRFIELD
MINIMUMS AT TIMES FOR KTRK/KTVL/KCXP. THERE WILL BE POCKETS OF VFR
CONDS OVER NEVADA AT TIMES, BUT WITH THE DEEP MOISTURE AND MORE
SHOWERS EXPECTED TODAY, MTN OBSCN AND REDUCED CIGS WILL CONTINUE
THROUGH AT LEAST 09Z. THE WORST CONDITIONS WILL BE IN THE SIERRA
AROUND TAHOE INCLUDING KTRK/KTVL. SNOW LEVELS WILL BE HIGHER TODAY
SO NO RUNWAY ACCUMULATION EXPECTED.
FOR KRNO, EXPECT OCCASIONAL MVFR CIGS/VIS IN SHOWERS WITH SOME VFR
CONDITIONS WHEN IT CLEARS. KCXP, IFR THRU 16Z THEN SIMILAR TO KRNO
AFTERWARD. KMMH, BELOW AIRFIELD MINIMUMS THROUGH 16Z, BUT WITH THE
MAIN PART OF THE SYSTEM HEADING NORTH, FLUCTUATION BETWEEN
MVFR/VFR CONDITIONS AFTERWARD.
WINDS ALSO INCREASE ALOFT WITH 10,000 FT WINDS AROUND 40-45 KTS.
THERE WILL BE SOME MTN WAVE TURBULENCE, BUT NOT AS BAD AS IT COULD
BE DUE TO THE DEEP MOISTURE. STILL, OCCASIONAL GUSTS WILL MIX DOWN
TO THE TERMINALS WITH PEAK GUSTS AROUND 25 KTS. IN ADDITION, WITH
MTN WAVES WEAKER, DO NOT EXPECT AS MUCH LLWS. STILL ABOUT A 20%
CHC OF IT OCCURRING AROUND KTVL AND KTRK.
IMPROVING CONDITIONS ALL AREAS AFTER 12Z THU ALTHOUGH IT WILL BE
SLOWER IN THE SIERRA DUE TO THE CONTINUED WEAK UPSLOPE FLOW. WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER STORM WARNING UNTIL 4 AM PST THURSDAY ABOVE 7000 FEET FOR
NVZ002.
CA...WINTER STORM WARNING UNTIL 4 AM PST THURSDAY ABOVE 7000 FEET FOR
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
942 AM MST WED DEC 3 2014
.UPDATE...
ISSUED AT 926 AM MST WED DEC 3 2014
WEAK UPPER LEVEL WAVE WILL BE MOVING ACROSS THE AREA TODAY WITH
SOME INCREASE IN LIGHT SNOWFALL EXPECTED IN THE MOUNTAINS. AREA
RADARS ARE LESS THAN IMPRESSIVE WITH CURRENT ECHO COVERAGE BUT A
HINT OF INCREASE LIGHT RETURNS SHOWING UP NOW ACROSS LARIMER
COUNTY. STILL CEILINGS ARE NOT THAT LOW. POP COVERAGE IN THE
MOUNTAINS MAY STILL BE TOO HIGH AND WILL LIKELY TAPER THIS DOWN A
BIT THIS AFTERNOON AND EVENING. CROSS NORTHEAST PLAINS...QUITE A
BIT OF MID/HIGH LEVEL CLOUD COVER WILL PERSIST THIS AFTERNOON WITH
COOLER TEMPERATURES FROM CLOUDS AND LAST EVENINGS WEAK FRONT. ONLY
MINOR CHANGES PLANNED FOR FORECAST.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 406 AM MST WED DEC 3 2014
MOISTURE GRADUALLY INCREASING OVER COLORADO FROM THE SOUTHWEST. SO
FAR IT APPEARS THAT SNOW IS SPOTTY AT BEST IN OUR AREA...THERE HAS
BEEN MORE WIDESPREAD LIGHT SNOW IN THE SAN JUAN MOUNTAINS
OVERNIGHT. WITHOUT MUCH LARGE SCALE LIFT AND MODEST WINDS THIS MAY
NOT CHANGE VERY QUICKLY AND IT MAY TURN OUT TO BE MORE CLOUDS THAN
SNOW. THERE IS A LITTLE SHORTWAVE IN THE FLOW THAT WILL PRODUCE
MORE FAVORABLE WINDS FOR OROGRAPHIC SNOW IN THE NORTHERN MOUNTAINS
THIS AFTERNOON AND EARLY EVENING...BUT AS THE WINDS AND MOISTURE
GET BETTER BEHIND THE TROUGH THERE WILL ALSO BE SUBSIDENCE...SO
AGAIN THE SNOW WILL LIKELY BE LIMITED TO WHAT THE WEAK OROGRAPHIC
EFFECTS CAN SQUEEZE OUT OF AN AIRMASS THAT WILL STILL NOT BE VERY
MOIST OR UNSTABLE. LEFT THE CURRENT FORECAST ALONE WITH ABOUT 2 TO
5 INCHES OF SNOW OVER THE NEXT 24 HOURS IN THE HIGH MOUNTAINS...BUT
THIS MAY EVEN BE TOO MUCH.
WITH THE WEAK WAVE PASSING LATE TODAY...THERE MAY BE A WINDOW FOR
INCREASED WINDS DOWN INTO THE FOOTHILLS AGAIN. FLOW IS A BIT LESS
THAN WITH THE LAST SEVERAL TROUGHS AND THE FAVORABLE PROFILE FOR
AMPLIFICATION IS ONLY AROUND FOR A LITTLE WHILE LATE TODAY. SO IT
DOES NOT LOOK LIKE MUCH OF A HIGH WIND THREAT...BUT PROBABLY
ANOTHER ROUND OF 40-60 MPH WIND GUSTS IN AREAS FAVORED IN WESTERLY
FLOW FOR A FEW HOURS.
WITH THE CLOUD COVER THE DIURNAL TEMPERATURE SWING WILL BE
LIMITED...CURRENT FORECAST IS ON THE COOL SIDE OF GUIDANCE TODAY
AND TONIGHT AND THIS LOOKS GOOD.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 406 AM MST WED DEC 3 2014
ON THURSDAY...THE FLOW ALOFT WILL REMAIN ZONAL WITH ANOTHER WEAK
EMBEDDED DISTURBANCE SLIPPING ACROSS SOUTHERN CO THURSDAY NIGHT.
THERE WILL BE SUFFICIENT MOISTURE COUPLED WITH FAVORABLE
OROGRAPHICS TO PRODUCE CHC POPS IN THE MOUNTAINS. FURTHER
EAST...DOWNSLOPE NEGATE ANY PCPN AND WILL ALLOW FOR WARMER
TEMPERATURES. ON FRIDAY AND SATURDAY...IT WILL BE DRY WITH A SHORT
WAVE RIDGE AXIS SLIPPING ACROSS COLORADO. THE PATTERN WILL REMAIN
PROGRESSIVE SUNDAY THROUGH TUESDAY. ANOTHER WEAK PACIFIC TROUGH IS
PROGGED TO MOVE ACROSS SOUTHERN CO LATE SATURDAY/SATURDAY NIGHT.
NOT MUCH OF THIS WL IMPACT THE CWA IN TERMS OF PCPN...WITH MUCH OF
THE QG ASCENT PASSING TO THE SOUTH. OVERALL WILL KEEP IT DRY WITH
TEMPERATURES IN THE LOWER 50S EACH AFTN. MORE RIDGING ON
MONDAY...WITH SFC LEE TROUGH DEVELOPING ALONG THE FRONT RANGE
MONDAY NIGHT INTO TUESDAY. ANOTHER TROUGH OVER THE PAC NORTHWEST
WITH SOME OF THIS MOISTURE POSSIBLY SLIPPING INTO THE NORTHERN
MOUNTAINS ON TUESDAY BUT FOR NOW WL KEEP POPS OUT OF THE GRIDS.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 926 AM MST WED DEC 3 2014
MAIN CHALLENGE WILL BE SURFACE WIND FORECAST AS DENVER CYCLONE
DEVELOPS DURING THE LATE AM/AFTERNOON HOURS. WINDS ALREADY
INCREASING FROM THE SOUTHEAST AT DENVER AND HAVE BEEFED UP WINDS
THERE ALREADY. QUESTION WILL BE HOW FAST THE CYCLONE SHIFTS TO THE
EAST THIS AFTERNOON. THE HRRR HAS WINDS SHIFTING NW AT APA/DEN IN
THE 19-20Z RANGE WHILE RAP IS SLOWER AND MORE IN THE 22-00Z RANGE.
APPEARS APA ALREADY TRENDING MORE W-NW AND MAY KEEP THAT DIRECTION
FOR THAT DAY ALONG WITH BJC. VFR WITH CLOUDS MAINLY IN THE MID AND
HIGH LEVEL VARIETY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ENTREKIN
SHORT TERM...GIMMESTAD
LONG TERM...COOPER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1250 PM EST WED DEC 3 2014
.SYNOPSIS...
A WARM FRONT WILL BRING A WINTRY MIX OF PRECIPITATION CHANGING TO
RAIN LATER THIS MORNING. MUCH MILDER WEATHER BRIEFLY RETURNS
TODAY. THURSDAY BEGINS A TREND TOWARDS COLDER BUT DRY CONDITIONS
LASTING INTO FRIDAY. A COLD FRONT WILL BRING A WINTRY MIX OF
PRECIP LATE FRI NIGHT INTO SAT. THEN A COASTAL LOW WILL BRING
ANOTHER SHOT OF WINTRY WEATHER MON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1230 PM UPDATE...
MAIN ISSUE IS THAT IMPROVING CONDITIONS WILL BE SLOW AS FRONTAL
PROGRESSION SLOWED BY A WAVE MOVING ALONG IT THIS AFTERNOON. HAVE
KEPT LIKELY POPS IN FOR SE HALF OF AREA REFLECTING RADAR TRENDS
AND LATEST MESOSCALE GUIDANCE...INCLUDING THE HRRR WHICH SEEMS TO
HAVE A GOOD HANDLE AT THE MOMENT ON THE DISTRIBUTION OF SHOWER
ACTIVITY. DO NOT SEE MUCH BREAK IN THE CLOUDS UNTIL AFTER THE NEAR
TERM PERIOD. THE CLOUDS WILL CONTINUE TO TEMPER THE POTENTIAL FOR
MILDER TEMPERATURES BY KEEPING AN INVERSION ACROSS MOST OF THE
AREA. WINDS COULD BECOME GUSTY QUICKLY AT ANY LOCATION WHERE THE
INVERSION BREAKS...WHICH MAKES THAT PART OF THE FORECAST
ESPECIALLY QUICKLY.
1030 AM UPDATE...
ADVISORIES HAVE BEEN ALLOWED TO EXPIRE AS MESONET OBS INDICATE
TEMPS ARE ABOVE FREEZING. LOTS OF LOW CLOUDS AND AREAS OF FOG
WHICH WILL CONTINUE INTO THE AFTERNOON. SHOWERS ARE MOVING ACROSS
CT AND INTO RI LATE THIS MORNING. EXPECT ADDITIONAL SHOWERS TO
DEVELOP INTO THE AFTERNOON AS MID LEVEL SHORTWAVE APPROACHES WITH
AN INCREASE IN UPPER LEVEL QG FORCING. MID LEVEL DRYING BEGINS
MOVING INTO THE WEST AFT 18Z SO THE FOCUS FOR SHOWERS WILL SHIFT
TO E HALF NEW ENG DURING THE AFTERNOON. INCREASED POPS TO LIKELY.
TEMPS IN THE LOWER 50S CAPE/ISLANDS AND THE MILDER AIR BEGINNING
TO EXPAND INTO S RI AND SE MA AND EXPECT THIS REGION TO SEE TEMPS
REACH INTO THE 50S...WITH 40S IN THE INTERIOR...BUT PROBABLY
HOLDING IN UPPER 30S NORTH CENTRAL AND NW MA. GUSTY SOUTHWEST
WINDS WILL DEVELOP ACROSS THE COASTAL PLAIN WITH GUSTS TO 30 MPH
POSSIBLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...
CONDITIONS WILL BE DRYING OUT AFTER A COLD FRONT MOVING ACROSS
THE REGION. NORTHWEST WINDS BEHIND THIS FRONT WILL REMAIN GUSTY...
WHICH WILL PREVENT TEMPERATURES FROM PLUMMETING.
THURSDAY...
HIGH PRESSURE IN SOUTHERN CANADA WILL MOVE INTO ONTARIO AND
QUEBEC. THIS WILL MAINTAIN DRY WEATHER ACROSS SOUTHERN NEW
ENGLAND...BUT ALSO SLIGHTLY BELOW NORMAL TEMPERATURES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* COLDER BUT DRY THRU FRIDAY
* A WINTRY MIX POSSIBLE LATE FRIDAY NIGHT INTO SATURDAY
* A COASTAL LOW IS EXPECTED TO IMPACT THE AREA MONDAY
OVERALL...00Z MODEL DATA IS IN GOOD AGREEMENT THROUGH THE LONG TERM
PERIOD. THERE ARE OF COURSE THE USUAL DISCREPANCIES IN TIMING BUT
THE GENERAL SYNOPTIC PATTERN IS IN GOOD AGREEMENT. HIGH PRESSURE
MOVING ACROSS NORTHERN NEW ENGLAND WILL ALLOW COLDER TEMPERATURES TO
FILTER INTO SOUTHERN NEW ENGLAND FRIDAY. LOW PRESSURE MOVES THROUGH
QUEBEC EARLY IN THE WEEKEND BRINGING A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY.
THEN SUNDAY NIGHT AND MONDAY...A COASTAL LOW WILL PASS BY SOUTHERN
NEW ENGLAND BRINGING PRECIPITATION TO THE AREA. ANOTHER HIGH
PRESSURE TO THE NORTH WILL ALLOW COLD AIR TO DRAIN DOWN AT THE
SURFACE RESULTING IN THE POTENTIAL FOR A WINTRY MIX OF PRECIPITATION
ACROSS THE INTERIOR WITH THIS COASTAL LOW.
DESPITE THE AGREEMENT BETWEEN THE OPERATIONAL GFS AND ECMWF ON THE
MONDAY STORM...THERE IS STILL SOME UNCERTAINTY WITH THE WEEKEND
STORM. THIS COMES FROM SEVERAL THINGS...INCLUDING THE TIME FRAME...
DIFFERENCES IN THE ENSEMBLES...AND THE CHANGES IN PTYPE THAT WOULD
RESULT FROM A CHANGE IN THE TEMPERATURE PROFILE.
THURSDAY NIGHT AND FRIDAY...HIGH PRESSURE MOVES THROUGH NORTHERN NEW
ENGLAND ALLOWING COLD AIR TO DRAIN INTO SOUTHERN NEW ENGLAND.
STILL...TEMPERATURES ARE EXPECTED TO BE RIGHT AROUND NORMAL FOR
EARLY DECEMBER.
FRIDAY NIGHT AND SATURDAY...LOW PRESSURE MOVES THROUGH QUEBEC
BRINGING A COLD FRONT THROUGH SOUTHERN NEW ENGLAND ON SATURDAY. THE
GFS DOES HAVE A STRONGER FRONT THAN THE ECMWF BUT THE EFFECTS ARE
LARGELY THE SAME WITH SHOWERY PRECIPITATION AHEAD OF AND WITH THE
FRONT. THIS PRECIPITATION IS LIKELY TO BE A WINTRY MIX WITH THE
POTENTIAL FOR SOME POCKETS OF FREEZING RAIN ALONG WITH SNOW AND
SLEET. WHILE QPF INDICATES SNOW AMOUNTS WILL BE LESS THAN ADVISORY
CRITERIA AND JUST A FEW HUNDREDTHS OF ICE...THERE IS POTENTIAL THAT
FREEZING RAIN WILL BE MORE EXTENSIVE THAN CURRENTLY FORECAST. WILL
HAVE TO WATCH THIS PERIOD CAREFULLY OVER THE NEXT COUPLE OF DAYS.
SUNDAY THROUGH TUESDAY...THIS PERIOD IS MOST UNCERTAIN WITH THE
POTENTIAL FOR A COASTAL STORM MOST LIKELY AFFECTING SOUTHERN NEW
ENGLAND SUNDAY NIGHT AND MONDAY. MODELS HAVE A FEW TIMING/TRACK
DIFFERENCES WITH THE OPERATIONAL ECMWF A BIT FASTER THAN THE
OPERATIONAL GFS. ECMWF ENSEMBLES LEND CREDENCE TO THE OPERATIONAL
GFS WHILE THE GFS ENSEMBLE MEMBERS ARE MORE UNCERTAIN ON TRACK.
POTENTIAL TRACKS ARE IN A FAIRLY NARROW ENVELOPE FROM TRACKING OVER
NANTUCKET TO OUTSIDE OF THE 40/70 BENCHMARK.
BECAUSE OF THE UNCERTAINTY WITH THE TRACK...THERE IS POTENTIAL FOR
JUST ABOUT ANYTHING FROM SNOW ACROSS A PORTION OF THE REGION TO A
WINTRY MIX ACROSS THE INTERIOR TO RAIN. THE MOST LIKELY SOLUTION
THAT WE ARE LOOKING AT RIGHT NOW IS FREEZING RAIN ACROSS THE
INTERIOR...AND RAIN ALONG THE COASTAL PLAIN.
FINALLY...BECAUSE THIS IS A COASTAL STORM AND TIDES ON THE EAST
COAST ARE RUNNING AROUND 11 FEET...THERE IS POTENTIAL FOR COASTAL
FLOODING ALONG THE EAST COAST. THIS DEPENDS LARGELY ON THE TRACK OF
THE STORM AS WELL AS HOW QUICKLY IT MOVES PAST SOUTHERN NEW ENGLAND
BUT IT IS SOMETHING TO WATCH OVER THE NEXT SEVERAL DAYS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THIS AFTERNOON...MODERATE CONFIDENCE. MAIN ISSUE IS TIMING OF THE
BREAK UP OF STRATUS AND FOG AREAS LATE THIS AFTERNOON/EVENING. WIDESPREAD
IFR/LIFR IN STRATUS AND FOG WILL LIKELY HOLD THROUGH MOST OF THE
AFTERNOON AND THEN LIFT TO MVFR W TO E IN THE 23Z TO 02Z TIME
PERIOD. SCT TO NUMEROUS SHOWERS EXPECTED ALONG AND SE OF A BOS-BDL
LINE. GUSTY SW WINDS DEVELOPING IN THE COASTAL PLAIN WITH G25-30KT
LIKELY WHEREVER THE INVERSION BREAKS.
TONIGHT...HIGH CONFIDENCE. ANY LINGERING MVFR CONDITIONS WILL
QUICKLY IMPROVE TO VFR.
THURSDAY...HIGH CONFIDENCE. VFR.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. IFR CIGS LIKELY TO
PERSIST THROUGH THE AFTERNOON BUT EXPECT VSBYS TO IMPROVE AS SW
WINDS INCREASE TOWARD 00Z.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. LOW CONFIDENCE ON
TIMING OF IMPROVING VSBYS INTO THE AFTERNOON.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
THURSDAY NIGHT...HIGH CONFIDENCE. VFR.
FRIDAY...MODERATE CONFIDENCE. INCREASING CLOUDS WILL LEAD TO
MVFR/IFR CIGS ACROSS MUCH OF THE AREA.
SATURDAY...LOW CONFIDENCE. MVFR/IFR CIGS WITH RAIN SHOWERS SE AND
POSSIBLE WINTRY MIX NW WILL SLOWLY IMPROVE AFTER COLD FRONT MOVES
THROUGH REGION.
SUNDAY...LOW CONFIDENCE. VFR TO START WILL GRADUALLY DIMINISH TO
MVFR/IFR CIGS AS CLOUDS INCREASE.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM...MODERATE CONFIDENCE.
TODAY...A SOUTHWEST LOW LEVEL JET OF 40-50 KT DEVELOPS THIS
AFTERNOON. STILL NOT CONFIDENT HOW MUCH OF THIS WIND WILL MIX
DOWN...AS STRONG WARM AIR ADVECTION WILL ESTABLISH A SHALLOW WE
ARE FAIRLY CONFIDENT IN SCA GUSTS TO 30 KT WITH LOW PROB OF
REACHING GALE FORCE GUSTS. NO GALE HEADLINES YET DUE TO
UNCERTAINTY BUT THIS WILL BE RE- EVALUATED IN FUTURE FORECASTS.
TONIGHT...SMALL CRAFT ADVISORIES NECESSARY DUE TO GUSTY WINDS
WHICH WILL BE SLOWLY RELAXING OVERNIGHT.
THURSDAY...WINDS AND SEAS GRADUALLY DIMINISH. MAY NEED TO MAINTAIN
SMALL CRAFT ADVISORIES ACROSS THE OUTER COASTAL WATERS FOR A TIME.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
THURSDAY NIGHT AND FRIDAY...WINDS AND SEAS REMAIN BELOW SMALL CRAFT
CRITERIA AS HIGH PRESSURE CRESTS NORTH OF THE WATERS.
SATURDAY AND SUNDAY...EASTERLY WINDS AND SEAS SLOWLY BUILD AS A COLD
FRONT APPROACHES THEN CROSSES THE WATERS SATURDAY AND LOW PRESSURE
APPROACHES THE WATERS FROM THE SOUTH ON SUNDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ231>234-
251.
SMALL CRAFT ADVISORY UNTIL 1 AM EST THURSDAY FOR ANZ230-236.
SMALL CRAFT ADVISORY UNTIL 5 AM EST THURSDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THURSDAY FOR ANZ250-254-
255.
SMALL CRAFT ADVISORY UNTIL NOON EST THURSDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/RLG/THOMPSON
NEAR TERM...BELK/KJC/RLG
SHORT TERM...BELK
LONG TERM...RLG
AVIATION...KJC/THOMPSON
MARINE...BELK/RLG
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
410 PM EST WED DEC 3 2014
.UPDATE...
BASED ON LATEST CURRENT SATELLITE TRENDS AND WIND FIELD...ALONG
WITH LATEST MODEL DATA...HAVE MOVED UP THE START TIME AND EXPANDED
COVERAGE OF THE DENSE FOG ADVISORY. FOG BANK HAS MOVED ONTO
BEACHES OVER NE FL...AND IS APPROACHING INTERSTATE 95 IN FLAGLER
AND ST JOHNS COUNTIES. LATEST NAM AND HRRR SHOW THIS AREA TO
CONTINUE TO PUSH INLAND THIS EVENING...WITH THIS AREA MOVING
ACROSS ENTIRE CWA DURING THE NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 55 74 54 70 / 10 10 10 10
SSI 59 67 56 69 / 10 0 10 10
JAX 56 73 56 73 / 0 10 10 10
SGJ 60 71 60 74 / 10 10 10 20
GNV 56 77 57 76 / 0 0 0 20
OCF 56 79 58 78 / 0 10 0 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY FROM 11 PM THIS EVENING TO 11 AM EST THURSDAY
FOR ALACHUA-BAKER-BRADFORD-CLAY-COLUMBIA-GILCHRIST-HAMILTON-
MARION-PUTNAM-SUWANNEE-UNION.
DENSE FOG ADVISORY UNTIL 11 AM EST THURSDAY FOR DUVAL-FLAGLER-
NASSAU-ST JOHNS.
GA...DENSE FOG ADVISORY FROM 11 PM THIS EVENING TO 11 AM EST THURSDAY
FOR APPLING-ATKINSON-BACON-BRANTLEY-CHARLTON-CLINCH-COFFEE-
ECHOLS-INLAND CAMDEN-INLAND GLYNN-JEFF DAVIS-PIERCE-WARE-
WAYNE.
DENSE FOG ADVISORY UNTIL 11 AM EST THURSDAY FOR COASTAL CAMDEN-
COASTAL GLYNN.
AM...DENSE FOG ADVISORY UNTIL 11 AM EST THURSDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-ALTAMAHA
SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH
TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-FERNANDINA BEACH
TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH
FL OUT 20 NM.
&&
$$
STRUBLE/ENYEDI
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
339 PM EST WED DEC 3 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 338 PM EST WED DEC 3 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR TROF
CENTERED FM HUDSON BAY INTO THE GREAT LKS DOWNSTREAM OF A RDG OVER
WRN CANADA. SHRTWV EMBEDDED WITHIN THE NW FLOW ALF IS TRACKING THRU
ONTARIO AND DRAGGING A COLD FNT THRU THE UPR LKS. WNW FLOW OF COLDER
AIR...WITH 12Z H85 TEMPS DOWN TO -17C AT INL...IN THE WAKE OF THIS
FROPA IS CAUSING SOME LES IN THE FAVORED SN BELTS. ALTHOUGH SOME MDT
SN SHOWERS IMPACTED THE FAVORED SN BELTS OVER THE W EARLIER THIS
AFTN WITH 3-6 INCHES OF SN FALLING JUST W OF BARAGA...DNVA/DEEP LYR
QVECTOR DVGC...SUBSIDENCE IN THE WAKE OF THIS DISTURBANCE AND THE
ADVECTION OF DRY NEAR SFC AIR UPSTREAM IN NRN MN IS LIMITING THE
INTENSITY OF THE SN SHOWERS THERE NOW. THE MORE NMRS MULTIPLE BAND
SN SHOWERS ARE NOW STREAMING INTO THE ERN CWA. EVEN WHERE THE SN
SHOWERS ARE NOT PARTICULARLY HEAVY...GUSTY WINDS THAT REACHED AS HI
AS 45-50 MPH/BLSN ARE RESULTING IN REDUCED VSBYS. LOOKING FARTHER TO
THE W...THERE IS A SFC HI PRES RDG OVER THE PLAINS...AND PWAT AS LO
AS 0.11 INCH AT ABERDEEN SDAKOTA /ABOUT 50 PCT OF NORMAL/. DESPITE
THIS DRYNESS...THERE ARE SOME HI CLDS MOVING THRU THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON LES AND WIND
TRENDS/TOTALS AS WELL AS MIN TEMPS TNGT.
LATE TODAY/TNGT...PERSISTENT DNVA/DEEP LYR QVECTOR DVGC/SUBSIDENCE
CONTRIBUTING TO 12HR H5 HGT RISES FCST IN EXCESS OF 150M BTWN 18Z
TODAY AND 06Z TNGT/LOWERING INVRN BASE TO H9-850 AS WELL AS THE
ADVECTION OF DRIER AIR WL TEND TO LIMIT LES INTENSITY. THERE COULD
BE A PERIOD OF MODERATE SN SHOWERS E OF MUNISING INTO THE EVNG
BEFORE THE DRIER LLVL AIR ARRIVES THERE. CONSIDERED AN LES ADVY FOR
THIS AREA WITH THE GUSTY WINDS/BLSN AND FAVORABLE FCST UVV WITHIN
THE DGZ BTWN ABOUT 2-5K FT...BUT NEGATIVE DYNAMICS/DRY ADVECTION
NOTED EARLIER AS WELL AS EXPECTED SHIFTING WINDS ASSOCIATED WITH
APRCHG SFC HI PRES FM THE PLAINS THAT WL LIMIT RESIDENCE TIME OF THE
BANDS INDICATES ADVY SN TOTALS WL NOT BE WIDESPREAD ENUF TO JUSTIFY
THE HEADLINE. ISSUED A SPECIAL WX STATEMENT FOR ALGER/LUCE COUNTIES
TO DISCUSS THE LES/BLSN/POTENTIAL FOR MINOR LK SHORE EROSION AND
FLOODING ACCOMPANYING THE LARGE WAVES FCST TO BUILD AS HI AS 13-15FT
THIS EVNG. CLOSER APRCH OF SFC HI PRES WITH BACKING/DIMINISHING
WINDS TOWARD THE SW LATE WL END ANY LINGERING LES OVER THE FAR W.
ALTHOUGH SOME HI CLDS MAY DRIFT E FM THE NRN PLAINS INTO THIS AREA
LATE...LIGHTER WINDS/DRY AIR WL ALLOW TEMPS TO FALL BLO ZERO NEAR
THE WI BORDER.
THU...AS THE UPR FLOW TENDS MORE ZONAL...SFC HI PRES IS FCST TO
SHIFT E TOWARD NEW ENGLAND. THE UPR LKS WL BE DOMINATED BY RETURN
SSW FLOW BTWN THIS DEPARTING SFC HI AND FALLING MSLP IN THE PLAINS.
SOME OF THE MODELS...MAINLY THE 12Z GLOBAL AND REGIONAL CNDN
MODELS...GENERATE SOME LGT PCPN UNDER LARGER SCALE ISENTROPIC
ASCENT. BUT SINCE STRONGER DEEP LYR QVECTOR CNVGC ASSOCIATED WITH
THIS WAA AND SOME DVPA IN ADVANCE OF A WEAK SHRTWV MOVING THRU
ONTARIO WL PASS TO THE N...THERE WL BE A CONTINUED FEED OF LLVL DRY
AIR AND THE LLVL FLOW WL REMAIN WEAKLY ACYC...WL TEND TOWARD THE
DRIER FCSTS. CONCERNED SOME LES COULD DVLP OFF LK MI DURING THE AFTN
WHEN A STRONGER SSW FLOW DVLPS THERE...BUT NAM FCST SDNGS SHOW LO
INVRN BASE NEAR H925 AND ENUF LLVL DRY AIR TO LIMIT THIS POTENTIAL.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 256 PM EST WED DEC 3 2014
MAY SEE SOME SNOW OVER NRN/ERN UPPER MI FRI AS A SHORTWAVE MOVES
NEAR OR N OF THE CWA. 00Z/02 ECMWF SHOWS THE MOST SNOW /STILL ONLY
0.10 INCHES OF QPF OR LESS/ AS IT HAS THE SHORTWAVE FARTHEST
S...WHILE OTHER MODELS BARELY HAVE ANY QPF. WILL KEEP SLIGHT CHANCE
POPS OVER THE NERN CWA...LINGERING INTO FRI NIGHT OVER THE E AS
COLDER AIR AND NW LOW LEVEL WINDS RESULT BEHIND THE SHORTWAVE...BUT
STILL NOT SUFFICIENT FOR MORE THAN ISOLATED LES.
1038MB SFC HIGH MOVES ACROSS THE CWA ON SAT...WITH INCREASING LOW
LEVEL WARMTH /850MB TEMPS INCREASING TO AROUND 2C/ IN SW FLOW BEHIND
THE HIGH ON SUN. CONFIDENCE DECREASES SUN THROUGH NEXT WED AS MODELS
DISAGREE SIGNIFICANTLY WITH A SHORTWAVE AND UPPER TROUGH MOVING
ACROSS THE REGION. WHILE TIMING IS NOT AGREED ON...850MB TEMPS
DROPPING INTO THE TEENS BELOW ZERO WILL LEAD TO LES BEHIND THE
SHORTWAVE/TROUGH SOMETIME MON INTO TUE. MODELS CONTINUE TO DISAGREE
SIGNIFICANTLY WITH THE PATTERN BEHIND THE TROUGH. WILL USE CONSENSUS
OF GUIDANCE BLENDED WITH PREVIOUS FORECAST FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 108 PM EST WED DEC 3 2014
ALTHOUGH A COLD AND GUSTY WNW FLOW WL PERSIST INTO THIS EVNG OVER
WRN UPR MI...DRY AIR MOVING IN FM MN WL RESULT IN DIMINISHING LES
AND IMPROVING CONDITIONS AT CMX AND IWD. THE MORE EXPOSED CMX
LOCATION WL SEE STRONGER WINDS/MORE BLSN AND THE LOWER IFR VSBYS
PERSISTING LONGER INTO THIS EVNG. AS THE FLOW BACKS MORE TO THE SW
TNGT...EXPECT CONDITIONS TO GO VFR AT IWD. ATLHOUGH LLVL DRYING MAY
LEAD TO VFR CONDITIONS AT TIMES AT CMX...UPSLOPE NATURE OF THE
LONGER LASTING W WIND WL LEAD TO MVFR CIGS FOR A GOOD PORTION OF THE
TIME UNTIL A WSHFT TO SW RESULTS IN SUSTAINED IMPROVEMENT ON THU
MRNG. ALTHOUGH CIGS MAY DIP AT TIMES TO MVFR THIS AFTN AT SAW UNDER
INCOMING THERMAL TROF...DOWNSLOPE NATURE OF THE WIND AND LLVL DRYING
WL RESULT IN PREDOMINANT VFR WX THERE. ALTHOUGH MID CLDS WL BE ON
THE INCRS ON THU...LINGERING LLVL DRY AIR WL RESULT IN PREDOMINANT
VFR CONDITIONS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 256 PM EST WED DEC 3 2014
STRONG WINDS AND LIGHT TO MODERATE FREEZING SPRAY POSSIBLE. A
EXITING LOW NEAR JAMES BAY WILL KEEP A WEAKENING TROUGH
ACROSS LAKE SUPERIOR. W-NW GALES OF 35-40KTS ARE EXPECTED INTO THIS
EVENING. THE TROUGH WILL BE REPLACED BY HIGH PRESSURE SYSTEM
OVERNIGHT INTO THURSDAY MORNING /WITH WINDS DIMINISHING/...BEFORE IT
EXITS INTO S QUEBEC LATE THURSDAY. A LOW SLIDING ACROSS S CENTRAL
CANADA THURSDAY AND THURSDAY NIGHT WILL CROSS LAKE SUPERIOR ON
FRIDAY. BEHIND THIS LOW...A HIGH WILL BUILD IN FROM THE N PLAINS
SATURDAY. THE HIGH WILL THEN PUSH ACROSS THE LOWER GREAT LAKES
SATURDAY NIGHT. A LOW PRESSURE SYSTEM MAY ORGANIZE OVER SOUTH
CENTRAL CANADA AND POSSIBLY CROSS INTO THE UPPER GREAT LAKES ON
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR LSZ248>251-265>267.
GALE WARNING UNTIL 9 PM EST THIS EVENING FOR LSZ244-245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1121 AM CST WED DEC 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 327 AM CST WED DEC 3 2014
A WEAK AREA OF ARCTIC HIGH PRESSURE ACROSS ERN
MT WILL BUILD SOUTHEAST AND FUSE WITH THE MODIFIED ARCTIC HIGH
ACROSS WRN NEB THIS MORNING. THE RESULT IS A DRY 1030MB HIGH WHICH
THEN MOVES EAST TODAY AND TONIGHT SETTING UP A RETURN FLOW. BY 12Z
THURSDAY WARM AIR HAS RETURNED TO THE FCST AREA WITH SFC LOW
PRESSURE OVER SCNTL SD. DEWPOINTS HAVE ALREADY BEEN ADJUSTED DOWN
TOWARD THE VERY DRY RAP MODEL WHICH PRODUCES DEWPOINTS IN THE SINGLE
DIGITS TODAY. THE TEMPERATURE FORECAST IS BASED SOLELY ON BIAS
CORRECTED MET...MAV AND ECS GUIDANCE FOR HIGHS CLOSE TO WHAT THE RAP
INDICATES...UPPER 30S TO LOWER 40S. A BATCH OF MID AND HIGH LEVEL
CLOUDS ACROSS THE COLORADO LIFTS EAST NORTHEAST TODAY. THE MODEL
CONSENSUS SUGGESTS THE DENSER MID LEVEL CLOUDS WOULD MOVE MOSTLY
ACROSS NWRN NEB THIS AFTN WITH SKIES CLEARING EARLY THURSDAY MORNING.
A SIMILAR STRATEGY IS IN PLACE TONIGHT FOR BIAS CORRECTED LOWS IN
THE TEENS AND 20S. THE STRONG RETURN FLOW SPENDS THE NIGHT WORKING
ITS WAY ACROSS THE FCST AREA LIMITING RADIATIONAL COOLING TO THE FEW
HOURS TOWARD MORNING WHEREBY WINDS WOULD DECOUPLE ACROSS SRN NEB BUT
REMAIN STRONG IN THE NORTHEAST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 327 AM CST WED DEC 3 2014
DRY WEATHER WILL CONTINUE THROUGH THE PERIOD ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA. A WESTERLY DOWNSLOPE CHINOOK WIND WILL
ADVECT 8 TO 10C H850 MB TEMPERATURES EASTWARD ACROSS THE AREA
THURSDAY. AS THIS AIR IS MIXED TO THE SURFACE...HIGHS SHOULD BE
WELL INTO THE 50S ACROSS WESTERN NEBRASKA...WITH 45 TO 52F FOR
AREAS FARTHER EAST. DESPITE THE WARMER AIR...FIRE WEATHER
CONDITIONS WILL REMAIN IN CHECK...AS SOME PACIFIC MOISTURE ACTUALLY
MAKES IT EAST OVER THE ROCKIES WITH DEW POINTS IN THE MID 20S TO
AROUND 30 DEGREES.
FOR FRIDAY AND THE WEEKEND...A COUPLE OF WEAK SYSTEMS WILL MOVE
ACROSS SOUTHERN CANADA. THIS WILL DRIVE A WEAK COLD FRONT SOUTH
INTO THE AREA FRIDAY. THE FRONT WILL LIFT BACK NORTH INTO THE
NORTHERN PLAINS AS A WARM FRONT SATURDAY AND SUNDAY...WITH A MILD
WEEKEND EXPECTED FOR OUR AREA. A STRONGER ALBERTA CLIPPER WILL
DIVE SOUTHEAST SUNDAY NIGHT INTO MONDAY ACROSS NORTH DAKOTA INTO
NORTHERN MINNESOTA. THIS COULD SEND A SHOT OF ARCTIC AIR INTO
NORTH CENTRAL THROUGH EASTERN NEBRASKA MONDAY. THIS WILL BE BRIEF
HOWEVER...WITH A RAPID RETURN OF SOUTHERLY WINDS AND WARMING
TEMPERATURES TUESDAY INTO WEDNESDAY AS ANOTHER PLUM OF WARM AIR
ALOFT MOVES EAST OFF THE HIGHER TERRAIN TO THE WEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1120 AM CST WED DEC 3 2014
VFR CONDITIONS WILL PREVAIL OVER WESTERN AND NORTH CENTRAL NEBRASKA
FOR THE NEXT 24 HOURS.
BROKEN HIGH CIGS AOA 15 KFT CONTINUE TO STREAM INTO THE AREA FROM
THE WEST AND WILL CONTINUE INTO THURSDAY MORNING. A FEW MODELS ARE
SHOWING A MVFR STRATUS DECK CREEPING NORTH TOWARD SOUTHWEST
NEBRASKA LATE TONIGHT...HOWEVER WILL LEAVE ANY MENTION OUT OF THE
KLBF TAF FOR NOW SINCE CONFIDENCE IN THIS SOLUTION IS LOW AT THIS
TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
317 PM EST WED DEC 3 2014
.SYNOPSIS...A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA
TONIGHT. SURFACE HIGH PRESSURE BUILDS OVER THE MID-ATLANTIC AND THE
CAROLINAS FOR THURSDAY AND FRIDAY...WHILE UPPER-LEVEL DISTURBANCES
MOVE OVER OR NEAR THE AREA. ANOTHER COLD FRONT MOVES THROUGH THE
REGION SATURDAY.
&&
.NEAR TERM /TONIGHT THROUGH THURSDAY NIGHT/...
AS OF 310 PM WEDNESDAY...
THE LATEST SURFACE ANALYSIS SHOWED THE SURFACE FRONT STILL WEDGED
AGAINST THE MOUNTAINS...BUT OVERNIGHT ALL OF THE GUIDANCE SUGGESTS
THIS FRONT WILL PUSH THROUGH CENTRAL NORTH CAROLINA. THE LATEST
VISIBLE IMAGE SHOWS SINCE 1815Z TO 19Z A RAPID INCREASE IN THINNING
AND/OR CLEAR PATCHES AND THIS TREND IS EXPECTED TO CONTINUE THROUGH
THE REST OF THE AFTERNOON INTO THE EVENING...PARTICULARLY AS THE
OROGRAPHIC CIRRUS ON INFRARED IMAGERY HAS STARTED TO DIMINISH OVER
THE MOUNTAINS FROM SOUTH TO NORTH. MORE DIFFICULT IS THE TREND OF
CONDITIONS OVERNIGHT...BASED ON THE BUFR SOUNDINGS...MOS GUIDANCE...
AND HRRR WRF OUTPUT.
WITH THE FRONT STILL TO THE NORTHWEST...AND WITH EROSION OF LOW
CLOUDS ONGOING BUT WITH DEW POINTS STILL HIGH...THINK THERE IS THE
POTENTIAL FOR FOG AND/OR LOW CLOUDS WITH THE GREATEST CHANCE OF THIS
ALONG AND SOUTH OF ABOUT U.S. 64 WHERE DEW POINTS ARE WELL INTO THE
50S. NEITHER THE SREF ENSEMBLE VISIBILITY GUIDANCE NOR THE HRRR WRF
SHOW THIS...BUT THE PATTERN SEEMS TO FIT AND IS NOTED BY THE
MAJORITY OF THE MOS GUIDANCE. AS SUCH...NOTED PATCHY FOG FOR PART OF
THE NIGHT IN THAT AREA. OTHERWISE...UNDER AN AVERAGE PARTLY CLOUDY
SKY...WITH SOME CLEAR PATCHES AT TIMES ESPECIALLY NORTH AND MORE
AREAS OF LOWER CLOUDS AND FOG POSSIBLE SOUTH...OVERNIGHT LOWS FROM
NEAR THE MID 30S TOWARD KTDF TO NEAR 45 IN THE FAR SOUTH.
THURSDAY AND THURSDAY NIGHT...A SERIES OF MID-LEVEL SHORTWAVES ARE
FORECAST BY THE NAM AND THE GFS TO MOVE THROUGH CENTRAL NORTH
CAROLINA IN THIS PERIOD. THE STRONGEST ON BOTH OF THOSE SETS OF
GUIDANCE IS THURSDAY...COINCIDENT WITH A MID-LEVEL WAVE MOVING EAST
OUT OF THE SOUTHERN PLAINS ON WATER VAPOR IMAGERY. DURING THIS
TIME...OVER MOST OF CENTRAL NORTH CAROLINA THERE SHOULD BE 850MB
THETA-E TROUGHINESS...SO OVERALL MOISTURE SHOULD BE LIMITED EXCEPT
IN THE UPPER-LEVELS...AND POSSIBLY IN THE BOUNDARY LAYER OVER THE
FAR SOUTH ALTHOUGH LIFT IS FORECAST TO BE MEAGER WITH BASICALLY
850MB DIVERGENCE AND LITTLE UPPER DIFFLUENCE. BY THURSDAY NIGHT...
OVERALL MOISTURE STARTS TO INCREASE ON THE WEST SIDE OF THE SURFACE
HIGH...WITH MORE OF THE MOISTURE INCREASE OVER THE MOUNTAINS INTO
VIRGINIA. BOTH THE GFS AND THE NAM SHOW SLIGHT ISENTROPIC LIFT ON
THE 300K SURFACE OVER THE NORTHWEST PIEDMONT THURSDAY NIGHT...WITH
THE GFS AND NAM BUFR SOUNDINGS NOTING MOISTENING OF THE 850MB LAYER
BUT WITH THE NAM SHOWING MORE MOISTENING OF THE MID-LAYERS. MOS
GUIDANCE POPS ARE CREEPING UP INTO THE 30S ESPECIALLY FROM RALEIGH
NORTH AND WEST...BUT GUIDANCE QPF STAYS JUST BELOW ZERO IN CENTRAL
NORTH CAROLINA AND HRRR WRF GUIDANCE KEEPS THE APPEARANCE OF ANY
MEASURABLE RAIN JUST TO OUR NORTH AND WEST. AVERAGING THE DRIER GFS
AND THE MORE MOIST NAM WITH THE HRRR AND MOS GUIDANCE SUGGESTS A
SLIGHT CHANCE OF RAIN OR SPRINKLES THURSDAY NIGHT MAINLY NORTH OF A
LINE FROM ABOUT KEXX TO KTDF.
1000-850MB THICKNESSES WOULD SUPPORT HIGHS AT LEAST A CATEGORY ABOVE
GUIDANCE FOR THURSDAY...BUT BEHIND THE FRONT AND WITH AT LEAST SOME
PERIODS OF HIGH CLOUDS...WILL LEAN TOWARD THE MOS GUIDANCE VALUES
WHICH ARE VERY CLOSE BETWEEN THE MET AND THE MAV...FOR HIGHS IN THE
LOWER TO MID 50S OVERALL. COULD SEE THE WARMER MAV MINIMUM
TEMPERATURES VERIFY THURSDAY NIGHT IF THERE ARE ENOUGH HIGH CLOUDS
THROUGHOUT CENTRAL NORTH CAROLINA...BUT WITH A RELATIVE MINIMUM FOR
A TIME THURSDAY EVENING ESPECIALLY EAST LEANED TOWARD THE WARMER MAV
WEST AND TOWARD A BLEND OR THE COOLER VALUES EAST...37 TO 42.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 310 PM WEDNESDAY...
FRIDAY...DRY AIR SURFACE RIDGE WILL EXTEND ACROSS THE FORECAST AREA
EMANATING FROM A PARENT HIGH (1040+MB) OVER NORTHERN NEW ENGLAND.
ALOFT A S/W WILL BE LIFTING NEWD FROM THE SOUTHERN PLAINS INTO THE
LOWER OH VALLEY. WESTERLY FLOW IN THE MID-UPPER LEVELS WILL ADVECT
MOISTURE FROM THIS SYSTEM INTO CENTRAL NC. THER COMBINATION OF A
COOL STABLE AIR MASS NEAR THE SURFACE AND THE INCREASINGLY MOIST AIR
MASS ALOFT SHOULD RESULT IN A VARIABLY CLOUDY AND SEASONABLY COOL
DAY OVER OUR REGION. THICKER CLOUDS ANTICIPATED ACROSS THE NW SHOULD
HOLD TEMPS BELOW 50 DEGREES. SOME POTENTIAL FOR PARTIAL/FILTERED SUN
IN THE SE WHICH WILL ALLOW TEMPS TO WARM SOLIDLY INTO THE 50S.
FRIDAY NIGHT...THE LOWER OH VALLEY SYSTEM WILL ADVANCE FARTHER EAST.
INCREASING SOUTHERLY FLOW ABOVE THE SURFACE-BASED COOL DOME SHOULD
INITIATE SOME OVERRUNNING OVER THE PIEDMONT LATE FRIDAY NIGHT/EARLY
SATURDAY. CURRENTLY EXPECT ANY PRECIP TO BE SPOTTY AND
LIGHT...MAINLY CONFINED TO AREAS WEST-NW OF HIGHWAY 1. MAY SEE AREAS
OF FOG AS WELL. MIN TEMPS MID-UPPER 40S.
SATURDAY AND SATURDAY NIGHT...S/W AND ATTENDANT SFC FRONT WILL
CONTINUE TO LIFT E-NE. THIS WILL BRING AN INCREASING THREAT FOR RAIN
ACROSS CENTRAL NC...ESPECIALLY LATE MORNING THROUGH EARLY EVENING.
RESIDUAL CAD AIR MASS MAY HOLD ON LONGER IN THE FAVORED NW PIEDMONT
THAN CURRENTLY ADVERTISED BY THE MODELS. PLAN TO HOLD MAX TEMPS IN
THE TRIA AROUND 50...THOUGH IMMEDIATELY EAST-AND SOUTH OF THIS
REGION...TEMPS SHOULD RECOVER INTO THE MID 50S. IF RAIN SPOTTY
ACROSS THE SE...MAX TEMPS IN VICINITY OF CLINTON...FAYETTEVILLE AND
GOLDSBORO MAY CLIMB INTO THE LOWER 60S.
BEGIN TO SEE MODEL SOLUTIONS DIVERGE BY SATURDAY NIGHT WITH THE MORE
PROGRESSIVE GFS SWINGS THE TROUGH ACROSS OUR REGION IN THE EVENING
WITH PRECIP CHANCES DWINDLING OVERNIGHT. THE ECMWF IS MORE
SLUGGISH...TRACKING AN UPPER LEVEL INTO THE MID ATLANTIC...WHICH
MAINTAINS A CYCLONIC FLOW OVER OUR REGION...KEEPING SKIES OVERCAST
AND A THREAT FOR RAIN CONTINUING ACROSS OUR EASTERN COUNTIES WELL
INTO THE NIGHT. DIFFICULT TO SAY WITH A HIGH DEGREE OF CONFIDENCE
WHICH MODEL IS MORE CORRECT AS THEY BOTH HAVE DISPLAYED DECENT RUN-
TO-RUN CONTINUITY. WILL LEAN TOWARD THE PESSIMISTIC ECMWF FOR NOW
AND SEE IF MODEL TREND ONE WAY BY TOMORROW. WITH THE LINGERING CLOUD
COVERAGE AND WEAK LOW LEVEL CAA...HAVE RAISED MIN TEMPS UP A COUPLE
OF DEGREES FROM PREVIOUS FORECAST. MIN TEMPS LOW-MID 40S.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 317 PM WEDNESDAY...
SUNDAY...FORECAST CONFIDENCE LOW AS HUGE DISPARITY AMONG MODEL
GUIDANCE THIS PERIOD. 12Z GFS DEPICTS A DRY AIR SURFACE RIDGE
EXTENDING ACROSS THE REGION. THIS WOULD RESULT IN SUNNY AND COOL
CONDITIONS. MEANWHILE THE 12Z ECMWF SLOWLY DRIFTS AN UPPER LEVEL
ACROSS THE CHESAPEAKE BAY REGION...MAINTAINING OVERCAST
SKIES...PATCHY LIGHT PRECIP AND COOL TEMPS ALONG WITH BRISK
CONDITIONS OVER OUR COASTAL PLAIN DUE TO PRESENCE OF A COASTAL LOW
OFFSHORE OF HATTERAS. PRESENTLY PREFER A WEAKER COUSIN OF THE 12Z
ECMWF AS SOME SEPARATION OF THE JET STREAMS EXPECTED. THIS YIELDS
BELOW NORMAL TEMPS WITH SOLID CHANCE FOR RAIN...MAINLY NORTH AND
EAST.
MONDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE REMAINS BELOW NORMAL
AS MEDIUM RANGE MODEL GUIDANCE OFFERING VARIED SOLUTIONS. DOES
APPEAR CERTAIN THAT WITH A L/W TROUGH OVER THE EASTERN U.S....HIGH
TEMPS WILL AVERAGE AT LEAST ONE TO TWO CATEGORIES BELOW NORMAL. IN
ADDITION...CLOUD COVERAGE WILL BE VARIABLE. GFS FAVORS LIGHT PRECIP
MONDAY-MONDAY EVENING WITH THE PASSAGE OF A SOUTHERN STREAM
SYSTEM...WHILE ECMWF FAVORS LATE TUESDAY INTO WEDNESDAY WHEN DIVES
ANOTHER SIGNIFICANT S/W SEWD FROM THE GREAT LAKES TOWARDS THE
SOUTHERN APPALACHIANS...SPINNING UP ANOTHER COASTAL LOW IN THE
PROCESS. FOR NOW...KEPT POPS MINIMAL (NO WORSE THAN SLIGHT
CHANCE/SMALL CHANCE).
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1255 PM WEDNESDAY...
SUB-VFR CONDITIONS CONTINUING ACROSS CENTRAL NORTH CAROLINA DURING
THE EARLY AFTERNOON SHOULD SLOWLY SHOW IMPROVEMENT...WITH MOSTLY VFR
CONDITIONS EXPECTED BY SUNSET. CONFIDENCE IS NOT REALLY HIGH AS SOME
OF THE MODEL SOUNDINGS SUGGEST CONTINUED MOISTURE SUCH THAT MVFR
CEILINGS COULD CONTINUE. HRRR WRF GUIDANCE CONTINUES TO FAVOR
GRADUAL EROSION OF THE LOWER CLOUDS THIS AFTERNOON. SHOULD THAT
HAPPEN...DURING THE NIGHT WITH DEW POINTS REMAINING HIGH AS LEAST
THROUGH THE EVENING WITH A LIGHT WIND...ANTICIPATE SOME AREAS OF FOG
WITH LOW CEILINGS SUCH THAT PERIODS OF SUB-VFR CONDITIONS SHOULD
OCCUR...HIGHEST PROBABILITY AND LONGEST LASTING TOWARD KFAY WHERE
THE LOW-LEVEL MOISTURE WILL BE HIGHEST. AS THE SURFACE FRONT MOVES
FARTHER SOUTH OF CENTRAL NORTH CAROLINA OVERNIGHT...ENOUGH DRY AIR
SHOULD PUSH FAR ENOUGH SOUTH THAT ALL OF CENTRAL NORTH CAROLINA WILL
BE PREVAILING VFR FOR THURSDAY MORNING. SOUTHWEST AND WEST SURFACE
WINDS GRADUALLY VEER WITH A WIDESPREAD NORTHEAST FLOW EXPECTED BY
12Z THURSDAY.
BEYOND THE 18Z VALID TAF PERIOD...A SERIES OF UPPER-LEVEL
DISTURBANCES WILL MOVE THROUGH OR NEAR CENTRAL NORTH CAROLINA
THURSDAY INTO FRIDAY. THERE IS A CHANCE OF SUB-VFR CONDITIONS... IF
IT OCCURS LIKELY MVFR CEILINGS...THURSDAY NIGHT INTO FRIDAY WITH A
FEW SPRINKLES OR A PASSING PATCH OF LIGHT RAIN MAINLY TOWARD KINT
AND KGSO. THE BETTER CHANCE OF SUB-VFR CONDITIONS AND AREAS OF RAIN
COMES OVERNIGHT FRIDAY INTO SATURDAY WITH THE MORE ADVERSE AVIATION
CONDITIONS EXPECTED TOWARD THE TRIAD AND KRDU. VFR CONDITIONS SHOULD
DEVELOP BEHIND A COLD FRONT SATURDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...WSS
LONG TERM...WSS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
312 PM EST WED DEC 3 2014
.SYNOPSIS...A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA
TONIGHT. SURFACE HIGH PRESSURE BUILDS OVER THE MID-ATLANTIC AND THE
CAROLINAS FOR THURSDAY AND FRIDAY...WHILE UPPER-LEVEL DISTURBANCES
MOVE OVER OR NEAR THE AREA. ANOTHER COLD FRONT MOVES THROUGH THE
REGION SATURDAY.
&&
.NEAR TERM /TONIGHT THROUGH THURSDAY NIGHT/...
AS OF 310 PM WEDNESDAY...
THE LATEST SURFACE ANALYSIS SHOWED THE SURFACE FRONT STILL WEDGED
AGAINST THE MOUNTAINS...BUT OVERNIGHT ALL OF THE GUIDANCE SUGGESTS
THIS FRONT WILL PUSH THROUGH CENTRAL NORTH CAROLINA. THE LATEST
VISIBLE IMAGE SHOWS SINCE 1815Z TO 19Z A RAPID INCREASE IN THINNING
AND/OR CLEAR PATCHES AND THIS TREND IS EXPECTED TO CONTINUE THROUGH
THE REST OF THE AFTERNOON INTO THE EVENING...PARTICULARLY AS THE
OROGRAPHIC CIRRUS ON INFRARED IMAGERY HAS STARTED TO DIMINISH OVER
THE MOUNTAINS FROM SOUTH TO NORTH. MORE DIFFICULT IS THE TREND OF
CONDITIONS OVERNIGHT...BASED ON THE BUFR SOUNDINGS...MOS GUIDANCE...
AND HRRR WRF OUTPUT.
WITH THE FRONT STILL TO THE NORTHWEST...AND WITH EROSION OF LOW
CLOUDS ONGOING BUT WITH DEW POINTS STILL HIGH...THINK THERE IS THE
POTENTIAL FOR FOG AND/OR LOW CLOUDS WITH THE GREATEST CHANCE OF THIS
ALONG AND SOUTH OF ABOUT U.S. 64 WHERE DEW POINTS ARE WELL INTO THE
50S. NEITHER THE SREF ENSEMBLE VISIBILITY GUIDANCE NOR THE HRRR WRF
SHOW THIS...BUT THE PATTERN SEEMS TO FIT AND IS NOTED BY THE
MAJORITY OF THE MOS GUIDANCE. AS SUCH...NOTED PATCHY FOG FOR PART OF
THE NIGHT IN THAT AREA. OTHERWISE...UNDER AN AVERAGE PARTLY CLOUDY
SKY...WITH SOME CLEAR PATCHES AT TIMES ESPECIALLY NORTH AND MORE
AREAS OF LOWER CLOUDS AND FOG POSSIBLE SOUTH...OVERNIGHT LOWS FROM
NEAR THE MID 30S TOWARD KTDF TO NEAR 45 IN THE FAR SOUTH.
THURSDAY AND THURSDAY NIGHT...A SERIES OF MID-LEVEL SHORTWAVES ARE
FORECAST BY THE NAM AND THE GFS TO MOVE THROUGH CENTRAL NORTH
CAROLINA IN THIS PERIOD. THE STRONGEST ON BOTH OF THOSE SETS OF
GUIDANCE IS THURSDAY...COINCIDENT WITH A MID-LEVEL WAVE MOVING EAST
OUT OF THE SOUTHERN PLAINS ON WATER VAPOR IMAGERY. DURING THIS
TIME...OVER MOST OF CENTRAL NORTH CAROLINA THERE SHOULD BE 850MB
THETA-E TROUGHINESS...SO OVERALL MOISTURE SHOULD BE LIMITED EXCEPT
IN THE UPPER-LEVELS...AND POSSIBLY IN THE BOUNDARY LAYER OVER THE
FAR SOUTH ALTHOUGH LIFT IS FORECAST TO BE MEAGER WITH BASICALLY
850MB DIVERGENCE AND LITTLE UPPER DIFFLUENCE. BY THURSDAY NIGHT...
OVERALL MOISTURE STARTS TO INCREASE ON THE WEST SIDE OF THE SURFACE
HIGH...WITH MORE OF THE MOISTURE INCREASE OVER THE MOUNTAINS INTO
VIRGINIA. BOTH THE GFS AND THE NAM SHOW SLIGHT ISENTROPIC LIFT ON
THE 300K SURFACE OVER THE NORTHWEST PIEDMONT THURSDAY NIGHT...WITH
THE GFS AND NAM BUFR SOUNDINGS NOTING MOISTENING OF THE 850MB LAYER
BUT WITH THE NAM SHOWING MORE MOISTENING OF THE MID-LAYERS. MOS
GUIDANCE POPS ARE CREEPING UP INTO THE 30S ESPECIALLY FROM RALEIGH
NORTH AND WEST...BUT GUIDANCE QPF STAYS JUST BELOW ZERO IN CENTRAL
NORTH CAROLINA AND HRRR WRF GUIDANCE KEEPS THE APPEARANCE OF ANY
MEASURABLE RAIN JUST TO OUR NORTH AND WEST. AVERAGING THE DRIER GFS
AND THE MORE MOIST NAM WITH THE HRRR AND MOS GUIDANCE SUGGESTS A
SLIGHT CHANCE OF RAIN OR SPRINKLES THURSDAY NIGHT MAINLY NORTH OF A
LINE FROM ABOUT KEXX TO KTDF.
1000-850MB THICKNESSES WOULD SUPPORT HIGHS AT LEAST A CATEGORY ABOVE
GUIDANCE FOR THURSDAY...BUT BEHIND THE FRONT AND WITH AT LEAST SOME
PERIODS OF HIGH CLOUDS...WILL LEAN TOWARD THE MOS GUIDANCE VALUES
WHICH ARE VERY CLOSE BETWEEN THE MET AND THE MAV...FOR HIGHS IN THE
LOWER TO MID 50S OVERALL. COULD SEE THE WARMER MAV MINIMUM
TEMPERATURES VERIFY THURSDAY NIGHT IF THERE ARE ENOUGH HIGH CLOUDS
THROUGHOUT CENTRAL NORTH CAROLINA...BUT WITH A RELATIVE MINIMUM FOR
A TIME THURSDAY EVENING ESPECIALLY EAST LEANED TOWARD THE WARMER MAV
WEST AND TOWARD A BLEND OR THE COOLER VALUES EAST...37 TO 42.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 310 PM WEDNESDAY...
FRIDAY...DRY AIR SURFACE RIDGE WILL EXTEND ACROSS THE FORECAST AREA
EMANATING FROM A PARENT HIGH (1040+MB) OVER NORTHERN NEW ENGLAND.
ALOFT A S/W WILL BE LIFTING NEWD FROM THE SOUTHERN PLAINS INTO THE
LOWER OH VALLEY. WESTERLY FLOW IN THE MID-UPPER LEVELS WILL ADVECT
MOISTURE FROM THIS SYSTEM INTO CENTRAL NC. THER COMBINATION OF A
COOL STABLE AIR MASS NEAR THE SURFACE AND THE INCREASINGLY MOIST AIR
MASS ALOFT SHOULD RESULT IN A VARIABLY CLOUDY AND SEASONABLY COOL
DAY OVER OUR REGION. THICKER CLOUDS ANTICIPATED ACROSS THE NW SHOULD
HOLD TEMPS BELOW 50 DEGREES. SOME POTENTIAL FOR PARTIAL/FILTERED SUN
IN THE SE WHICH WILL ALLOW TEMPS TO WARM SOLIDLY INTO THE 50S.
FRIDAY NIGHT...THE LOWER OH VALLEY SYSTEM WILL ADVANCE FARTHER EAST.
INCREASING SOUTHERLY FLOW ABOVE THE SURFACE-BASED COOL DOME SHOULD
INITIATE SOME OVERRUNNING OVER THE PIEDMONT LATE FRIDAY NIGHT/EARLY
SATURDAY. CURRENTLY EXPECT ANY PRECIP TO BE SPOTTY AND
LIGHT...MAINLY CONFINED TO AREAS WEST-NW OF HIGHWAY 1. MAY SEE AREAS
OF FOG AS WELL. MIN TEMPS MID-UPPER 40S.
SATURDAY AND SATURDAY NIGHT...S/W AND ATTENDANT SFC FRONT WILL
CONTINUE TO LIFT E-NE. THIS WILL BRING AN INCREASING THREAT FOR RAIN
ACROSS CENTRAL NC...ESPECIALLY LATE MORNING THROUGH EARLY EVENING.
RESIDUAL CAD AIR MASS MAY HOLD ON LONGER IN THE FAVORED NW PIEDMONT
THAN CURRENTLY ADVERTISED BY THE MODELS. PLAN TO HOLD MAX TEMPS IN
THE TRIA AROUND 50...THOUGH IMMEDIATELY EAST-AND SOUTH OF THIS
REGION...TEMPS SHOULD RECOVER INTO THE MID 50S. IF RAIN SPOTTY
ACROSS THE SE...MAX TEMPS IN VICINITY OF CLINTON...FAYETTEVILLE AND
GOLDSBORO MAY CLIMB INTO THE LOWER 60S.
BEGIN TO SEE MODEL SOLUTIONS DIVERGE BY SATURDAY NIGHT WITH THE MORE
PROGRESSIVE GFS SWINGS THE TROUGH ACROSS OUR REGION IN THE EVENING
WITH PRECIP CHANCES DWINDLING OVERNIGHT. THE ECMWF IS MORE
SLUGGISH...TRACKING AN UPPER LEVEL INTO THE MID ATLANTIC...WHICH
MAINTAINS A CYCLONIC FLOW OVER OUR REGION...KEEPING SKIES OVERCAST
AND A THREAT FOR RAIN CONTINUING ACROSS OUR EASTERN COUNTIES WELL
INTO THE NIGHT. DIFFICULT TO SAY WITH A HIGH DEGREE OF CONFIDENCE
WHICH MODEL IS MORE CORRECT AS THEY BOTH HAVE DISPLAYED DECENT RUN-
TO-RUN CONTINUITY. WILL LEAN TOWARD THE PESSIMISTIC ECMWF FOR NOW
AND SEE IF MODEL TREND ONE WAY BY TOMORROW. WITH THE LINGERING CLOUD
COVERAGE AND WEAK LOW LEVEL CAA...HAVE RAISED MIN TEMPS UP A COUPLE
OF DEGREES FROM PREVIOUS FORECAST. MIN TEMPS LOW-MID 40S.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 310 PM WEDNESDAY...
TO BE ISSUED SHORTLY...
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1255 PM WEDNESDAY...
SUB-VFR CONDITIONS CONTINUING ACROSS CENTRAL NORTH CAROLINA DURING
THE EARLY AFTERNOON SHOULD SLOWLY SHOW IMPROVEMENT...WITH MOSTLY VFR
CONDITIONS EXPECTED BY SUNSET. CONFIDENCE IS NOT REALLY HIGH AS SOME
OF THE MODEL SOUNDINGS SUGGEST CONTINUED MOISTURE SUCH THAT MVFR
CEILINGS COULD CONTINUE. HRRR WRF GUIDANCE CONTINUES TO FAVOR
GRADUAL EROSION OF THE LOWER CLOUDS THIS AFTERNOON. SHOULD THAT
HAPPEN...DURING THE NIGHT WITH DEW POINTS REMAINING HIGH AS LEAST
THROUGH THE EVENING WITH A LIGHT WIND...ANTICIPATE SOME AREAS OF FOG
WITH LOW CEILINGS SUCH THAT PERIODS OF SUB-VFR CONDITIONS SHOULD
OCCUR...HIGHEST PROBABILITY AND LONGEST LASTING TOWARD KFAY WHERE
THE LOW-LEVEL MOISTURE WILL BE HIGHEST. AS THE SURFACE FRONT MOVES
FARTHER SOUTH OF CENTRAL NORTH CAROLINA OVERNIGHT...ENOUGH DRY AIR
SHOULD PUSH FAR ENOUGH SOUTH THAT ALL OF CENTRAL NORTH CAROLINA WILL
BE PREVAILING VFR FOR THURSDAY MORNING. SOUTHWEST AND WEST SURFACE
WINDS GRADUALLY VEER WITH A WIDESPREAD NORTHEAST FLOW EXPECTED BY
12Z THURSDAY.
BEYOND THE 18Z VALID TAF PERIOD...A SERIES OF UPPER-LEVEL
DISTURBANCES WILL MOVE THROUGH OR NEAR CENTRAL NORTH CAROLINA
THURSDAY INTO FRIDAY. THERE IS A CHANCE OF SUB-VFR CONDITIONS... IF
IT OCCURS LIKELY MVFR CEILINGS...THURSDAY NIGHT INTO FRIDAY WITH A
FEW SPRINKLES OR A PASSING PATCH OF LIGHT RAIN MAINLY TOWARD KINT
AND KGSO. THE BETTER CHANCE OF SUB-VFR CONDITIONS AND AREAS OF RAIN
COMES OVERNIGHT FRIDAY INTO SATURDAY WITH THE MORE ADVERSE AVIATION
CONDITIONS EXPECTED TOWARD THE TRIAD AND KRDU. VFR CONDITIONS SHOULD
DEVELOP BEHIND A COLD FRONT SATURDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...WSS
LONG TERM...WSS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1224 PM EST WED DEC 3 2014
.SYNOPSIS...
HIGH PRESSURE TO OUR NORTH WILL BRING CLOUDY AND COOL WEATHER
THROUGH FRIDAY. AFTER A ONE DAY WARM-UP ON SATURDAY A NEW HIGH
WILL BUILD IN FROM THE NORTH AGAIN ON SUNDAY...BRINGING BACK
CLOUDY AND COOLER CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 PM WEDNESDAY...VISIBILITIES HAVE RAPIDLY IMPROVED OVER
THE PAST HOUR WITH SKIES ALSO SCATTERING OUT...MAINLY OVER THE
COASTAL COUNTIES. EXPECT THIS TREND TO CONTINUE INTO THE AFTERNOON
HOURS. PREVIOUS DISCUSSION FROM EARLY THIS MORNING FOLLOWS:
THE COLD FRONT THAT PUSHED SOUTHWARD ACROSS THE AREA LESS THAN 24
HOURS AGO IS STALLED OFFSHORE. THE BOUNDARY IS EASILY DISCERNIBLE
IN 11-3.9 MICRON SATELLITE IMAGERY, LYING APPROXIMATELY 30 MILES
OFFSHORE. (THE FRYING PAN SHOALS BUOY, STILL REPORTING NE WINDS,
IS VERY NEAR THE INFERRED FRONTAL POSITION.) LOW STRATUS AND FOG
COVERS THE AREA WEST OF THE FRONT AND A DENSE FOG ADVISORY HAS
BEEN ISSUED FOR ALL OF OUR COUNTIES THROUGH 10 AM. 00Z MODEL
SOUNDINGS AGREE WITH LAST NIGHT`S 00Z MHX OBSERVED SOUNDING
SHOWING THIS IS A VERY SHALLOW COOL AIRMASS EXTENDING ONLY UP
THROUGH 1500 FEET AGL BEFORE SOUTHWEST WINDS BEGIN ALOFT.
THE FORECAST FOR TODAY IS ONE OF LOW CONFIDENCE DUE TO UNCERTAINTY
IN HOW QUICKLY WE CAN BURN THROUGH THE FOG AND LOW STRATUS. SUN
ANGLES ARE NEARLY AS LOW AS THEY GET SO WE`LL DEPEND JUST AS MUCH
ON MECHANICAL MIXING FROM ABOVE AS DIABATIC HEATING FROM BELOW TO
GET THE CLOUDS OUT. THE 00Z GFS AND ECMWF ERODE THE MESS RATHER
QUICKLY AND THEREFORE SHOW THE POTENTIAL FOR TEMPERATURES IN THE
70S THIS AFTERNOON. OTHER GUIDANCE INCLUDING THE 00Z NAM AND THE
ARW AND NMM VERSIONS OF THE NAM SHOW A SLOWER EROSION OF THE
CLOUDS AND SUBSEQUENTLY COOLER TEMPERATURES TODAY. MY FORECAST
(BASED MOST CLOSELY ON THE 00Z OPERATIONAL AND NMM VERSIONS OF THE
NAM) ERODES CLOUDS EARLY IN THE AFTERNOON WITHIN 20 MILES OF THE
SANTEE RIVER WITH FORECAST HIGHS THERE IN THE LOWER 70S...BUT
HANGS ONTO CLOUDS INTO THE MID AFTERNOON ELSEWHERE WITH HIGHS ONLY
IN THE 60S. QUITE CONCERNING IS THE NEW 08Z RUN OF THE RUC MODEL
WHICH SHOWS TEMPERATURES HOLDING IN THE 50S ACROSS MOST OF THE
AREA THIS AFTERNOON...WITH ANY CLEARING HOLDING OFF UNTIL JUST
BEFORE SUNSET.
THE NEXT SYNOPTIC HIGH CURRENTLY ENTERING THE WESTERN HIGH PLAINS
WILL PUSH A COLD FRONT SOUTHWARD ACROSS THE AREA TONIGHT. WINDS
SHOULD BECOME NORTHEAST AFTER MIDNIGHT. THIS NEW COOL AIRMASS
SHOULD ARRIVE ON NORTHEAST WINDS THAT HAVE PICKED UP ENOUGH
ATLANTIC MOISTURE TO KEEP CLOUDS AGAIN IN PLACE. LOWS SHOULD FALL
TO NEAR 50.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NOT EXPECTING TO MUCH IN THE WAY OF
SUNSHINE THROUGH THE PERIOD. HIGH PRESSURE MOVES EAST JUST NORTH
OF NEW YORK THURSDAY THROUGH FRIDAY WITH A RIDGE AXIS DEVELOPING
INTO THE CAROLINAS. THE RESULTING NE FLOW A THE SURFACE WILL
PROVIDE GENTLE ASCENT VIA UNDERCUTTING TO MAINTAIN AN ALREADY VERY
MOIST LAYER JUST ABOVE THE INVERSION. FCST SOUNDINGS SHOW AMPLE
MOISTURE IN THE 1-4KFT RANGE. SOME HINTING AT THIS MOISTURE MIXING
OUT SOME BY FRIDAY BUT GIVEN THE RELATIVELY NEGLIGIBLE CHANGE IN
THE SYNOPTIC SETUP THIS IS LIKELY IN ERROR. BOTH DAYS LOOK FAIRLY
DREARY WITH SHALLOW MIXING THAT SHOULD CAP HIGH TEMPS TO WITHING A
FEW DEGREES OF 60. ABOVE THE AFOREMENTIONED MOIST LAYER WILL BE A
LAYER THAT IS DRY ENOUGH TO KEEP MEASURABLE PRECIP HARD-PRESSED TO
COME BY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...THE WEDGE PRESENT FOR THE DURATION OF THE
SHORT TERM BREAKS DOWN ON SATURDAY JUST IN TIME FOR A COLD FRONT
TO ARRIVE. DEPENDING ON HOW MUCH DEEP LAYER MOISTURE MANAGES TO
FLOW INTO THE CAROLINAS AHEAD OF THIS BOUNDARY THERE SHOULD BE
SOME REASONABLE INCREASE IN RAINFALL CHANCES. THE AFTERNOON WILL
TURN OUT A BIT WARMER ESPECIALLY IN AREAS THAT MANAGE TO SEE
ENOUGH SUNSHINE. SOON AFTER THE SATURDAY NIGHT FROPA AN ALL-TOO-
FAMILIAR WEDGE SETUP RETURNS BY SUNDAY THAT SHOULD PERSIST INTO
MONDAY IF NOT LONGER. WHILE THIS WILL NOT LEAD TO ANY
SIGNIFICANTLY COOL AIR...MOST PLACES WILL RETURN TO HIGHS JUST SHY
OF 60...IT MAY MEAN A CONTINUATION OF LITTLE SUNSHINE.
&&
.AVIATION /18Z WEDNESDAY THROUGH SUNDAY/...
AS OF 18Z..PESKY STRATUS MAY HANG IN FOR A GOOD PORTION OF THE
AFTERNOON...HOWEVER EXPECTING CONTINUED CLEARING OVERALL. EVEN
THOUGH THE LAYER IS VERY SHALLOW...THE SUN ANGLE IS PROVIDING
LITTLE IN THE WAY OF SOLAR INSOLATION. EVEN IF THE ENTIRE ARE
SCATTERS OUT...MODELS ARE IN GOOD AGREEMENT IN BRINGING IT RIGHT
BACK IN AFTER SUNSET. WENT WITH THIS SCENARIO WITH ANOTHER ROUND
OF LIFR/VLIFR THROUGH THE OVERNIGHT HOURS. THERE MAY BE AN
IMPROVEMENT TOWARD MORNING...PARTICULARLY THE VISIBILITY AS A
REINFORCEMENT OF THE WEDGE WILL BUMP UP THE WINDS TO 5 KTS OR SO.
THURSDAY...LOOK FOR A SLOW IMPROVEMENT WITH ONLY MVFR EXPECTED BY
THE END OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...A SERIES OF WEDGES WILL KEEP THE WEATHER
UNSETTLED THROUGH MONDAY WITH INTERMITTENT IFR CONDITIONS AND
SEVERAL CHANCES OF LIGHT PRECIP.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 PM WEDNESDAY...HAVE EXTENDED DENSE FOG ADVISORY UNTIL
4 PM FOR ALL WATERS. OTHERWISE FORECAST CONTINUES UNCHANGED.
LATEST OBS SHOW VERY LIGHT NORTHERLY WINDS WITH 2 TO 3 FT SEAS.
PREVIOUS DISCUSSION FOLLOWS:
THE COLD FRONT THAT PUSHED SOUTH ACROSS THE AREA YESTERDAY MORNING
IS STALLED 30 MILES OFFSHORE. THE FRYING PAN SHOALS BUOY, STILL
REPORTING NE WINDS, IS VERY NEAR THE INFERRED POSITION OF THE
FRONT. WEST OF THE FRONT INCLUDING OVER THE COASTAL WATERS THIS NE
WIND CONTINUES THIS MORNING WITH LOW CLOUDS AND AREAS OF DENSE
FOG.
THE FORECAST FOR TODAY IS ONE OF FAIRLY LOW CONFIDENCE. HOW
QUICKLY THE COOL WEDGE AIRMASS WEST OF THE FRONT BREAKS DOWN WILL
DETERMINE WHETHER WINDS VEER AROUND TO THE SOUTH TODAY OR REMAIN
NORTHERLY. MY BET IS THE WEDGE WILL BE TENACIOUS AND NOT BREAK
UNTIL FAIRLY LATE IN THE DAY. THIS MEANS A LIGHT NORTHERLY WIND
SHOULD CONTINUE WITHIN 20 MILES OF SHORE. SEA FOG SHOULD BEGIN TO
DISSIPATE LATE IN THE MORNING BUT VISIBILITIES MAY NOT IMPROVE
BEYOND OVER 2-3 MILES UNTIL MID AFTERNOON.
HIGH PRESSURE BUILDING EASTWARD FROM THE PLAINS STATES WILL PUSH
ANOTHER COLD FRONT SOUTH ACROSS THE AREA TONIGHT. THIS WILL LEAD
TO INCREASING NORTH-NORTHEAST WINDS LATE TONIGHT, POSSIBLY
APPROACHING 20 KNOTS BY DAYBREAK THURSDAY.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NORTHERN ZONES MAY BE CLOSE TO ADVISORY
THRESHOLDS AS WEDGE OVER LAND PINCHES GRADIENT JUST ENOUGH FOR
SOME 6 FT SEAS. THE COAST PARALLEL FLOW WILL MAKE FOR A GRADIENT
IN NEARSHORE VS OFFSHORE WAVE HEIGHT AND SO ANY FLUCTUATION IN
WIND DIRECTION COULD PUSH ADVISORY-WORTHY SEAS INTO OR OUT OF THE
FCST ZONES. THE ONLY CHANGE HEADING INTO FRIDAY WILL BE A GRADUAL
EASING OF THE GRADIENT BUT IT MAY BE JUST ENOUGH TO DROP THE
MARGINAL ADVISORY IF ANY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...WINDS ACQUIRE A SOUTHERLY COMPONENT ON
SATURDAY AS THE SHORT TERM WEDGE BREAKS DOWN AND A COLD FRONT
APPROACHES FROM THE WEST. THIS BOUNDARY WILL PUSH THROUGH SATURDAY
NIGHT ALLOWING FOR ANOTHER WEDGE OF HIGH PRESSURE TO SEEP DOWN THE
EAST FACE OF THE APPALACHIANS. NORTH TO NORTHEASTERLY FLOW WILL
RETURN TO THE COASTAL WATERS AND THE GRADIENT MAY RAMP UP
SUFFICIENTLY THAT HEADLINES OR ADVISORY BECOMES NEEDED AGAIN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR AMZ250-
252-254-256.
&&
$$
SYNOPSIS...MBB
NEAR TERM...REK/TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...DL
MARINE...REK/TRA/MBB
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1257 PM EST WED DEC 3 2014
.SYNOPSIS...A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA
TONIGHT. SURFACE HIGH PRESSURE BUILDS OVER THE MID-ATLANTIC AND THE
CAROLINAS FOR THURSDAY AND FRIDAY...WHILE UPPER-LEVEL DISTURBANCES
MOVE OVER OR NEAR THE AREA. ANOTHER COLD FRONT MOVES THROUGH THE
REGION SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...
THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE OVER CENTRAL NORTH
CAROLINA WITH A SURFACE FRONT STALLED FOR NOW AGAINST THE
MOUNTAINS...AND A WEAK...DIFFUSE BOUNDARY WELL TO OUR SOUTH. CLOUDS
WERE WIDESPREAD OVER THE AREA...AND WHILE OBSERVATIONS WERE SHOWING
THE VISIBILITIES IN THE FOG SLOWLY IMPROVING...THERE WAS A GOOD
INVERSION ON THE KGSO SOUNDING EMPHASIZED BY THE RELATIVE WARMTH TO
ABOVE 10C NEAR 900MB AND ON THE KRNK SOUNDING AS WELL SHOWING NEAR
10C AT 850MB. WITH THAT INVERSION IN PLACE...THINK THE CLEARING
SHOULD BE SLOW. THE GFS IS FASTER WITH THE CLEARING...WITH ITS BUFR
SOUNDINGS INDICATING NUMEROUS BREAKS LIKELY BY 18Z...WHILE THE NAM
BUFR SOUNDINGS WOULD INDICATE MORE BETWEEN 18Z AND 21Z. THE LATTER
IS MORE CONSISTENT WITH THE LATEST HRRR WRF GUIDANCE...AND FOR THE
UPDATE IN THE GRIDDED FORECAST WAS A LITTLE MORE PESSIMISTIC AND
HELD ONTO MORE CLOUDS INTO THE AFTERNOON EVEN TOWARD THE SANDHILLS
AND SOUTHERN COASTAL PLAIN. WHILE THE RAP FORECAST A MODEST MID-
LEVEL WAVE MOVING THROUGH SOUTHERN VIRGINIA THIS AFTERNOON...LIFT
WAS WEAK AND MID-LEVEL MOISTURE WEAK AS WELL...SO PRECIPITATION
CHANCES WILL BE BELOW SLIGHT SAVE FOR STILL LIMITED POTENTIAL OF
SPOTTY DRIZZLE THIS MORNING. LEANED TOWARD THE COOLER MET MOS
GUIDANCE FOR HIGHS THIS AFTERNOON...WHICH IS WELL ON THE COLD END OF
THE GUIDANCE SUITE BUT CONSISTENT WITH THE PREVIOUS FORECAST. EDGED
THE FORECAST A LITTLE COOLER IN THE SANDHILLS AND COASTAL
PLAIN...ANTICIPATING CURRENTLY LATE-DAY HIGHS APPROACHING 60 IN THE
FAR NORTHWEST PIEDMONT...AND 60 TO 65 ELSEWHERE. WITH THE SOUTHWEST
FLOW IN PLACE...SEEN EVEN ON THE LOWEST GATE OF THE WSR-88D VWP AND
IN PROFILER DATA...ANY EVEN THIN SPOTS IN THE OVERCAST SHOULD RESULT
IN QUICK WARMING. -DJF
TEMPS THIS EVENING WILL BE A FUNCTION OF CLOUD COVER...FOLLOWED BY
COLD ADVECTION TONIGHT AS A COLD FRONT SURGES INTO CENTRAL NC FROM
THE N/NW. THE LATEST GUIDANCE SUGGESTS FROPA MAY OCCUR AS EARLY AS
03-06Z...WITH A GOOD 6-9 HOURS OF COLD ADVECTION PRIOR TO SUNRISE.
EXPECT LOWS RANGING FROM ~40F NEAR THE VA BORDER TO MID/UPPER 40S
NEAR THE SC BORDER. -VINCENT
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 330 AM WEDNESDAY...
LOW OVERCAST PREVIOUSLY PROGGED TO DEVELOP FROM THE SOUTH (OR FROM
SW-NE) MID TO LATE THU MORNING IN THE WAKE OF THE BACKDOOR COLD
FRONT APPEARS INCREASINGLY UNLIKELY TO OCCUR DUE TO LIGHT SOUTHERLY
FLOW /MARGINAL WARM ADVECTION/ ATOP THE SHALLOW COLDER AIRMASS
ADVANCING INTO THE REGION FROM THE NORTH. REGARDLESS...BROKEN/
OVERCAST CEILINGS AT ~15 KFT ARE EXPECTED TO MOVE INTO THE REGION
FROM THE WEST THROUGHOUT THE DAY...RESULTING IN MOSTLY CLOUDY SKIES
AND...ULTIMATELY...LITTLE DIURNAL VARIATION WITH HIGHS IN THE
MID/UPPER 40S AND LOWS THU NIGHT IN THE LOWER 40S. -VINCENT
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...
THE ROLLER COASTER RIDE IN TEMPERATURES SHOULD CONTINUE INTO NEXT
WEEK...
A WHOLE HOST OF PACIFIC STORM SYSTEMS ARE EXPECTED TO DRIVE INTO THE
WEST COAST... THEN ENCOUNTER A A SPLIT FLOW PATTERN AS THEY COME
EASTWARD FROM THE ROCKIES TO THE MID-ATLANTIC COAST. IT IS STILL
UNCLEAR IF ANY PHASING OF THE TWO JETS (THE POLAR JET AND THE ACTIVE
SUBTROPICAL JET) WILL OCCUR OVER THE EASTERN UNITED STATES DURING
THIS PERIOD. THE CONSENSUS IS FOR THE SUBTROPICAL JET TO REMAIN THE
MORE DOMINATE FLOW... WITH AT LEAST SOME PHASING OF THE FLOW THAT
WOULD MOST LIKELY BE OFFSHORE IN THE ATLANTIC EARLY TO MID NEXT
WEEK.
REGARDLESS... THE MID AND UPPER LEVEL SPLIT FLOW PATTERN WITH A
RELATIVELY DOMINATE SUBTROPICAL FLOW OVER OUR REGION FAVORS A STORM
TRACK THAT WOULD DELIVER THE MOST SIGNIFICANT RAINS TO THE TENNESSEE
VALLEY INTO THE APPALACHIANS TO THE MID-ATLANTIC COAST LATE FRIDAY
INTO SUNDAY. THIS WOULD INCLUDE AT LEAST THE NW QUADRANT OF OUR
REGION... IF NOT MOST FOR AT LEAST SOME DECENT RAINFALL OVER THE
WEEKEND.
WE WILL BEGIN THE FORECAST BASED ON HPC MODEL PREFERENCES INCLUDING
THE LATEST 00Z/03 DECEMBER OPERATIONAL EC AND GFS RUNS THAT
INDICATE THE PROGRESSION OF THE WET SYSTEMS FROM WEST TO EAST BUT
KEEP SOME SEPARATION IN THE TWO JET STREAMS INTACT THROUGH SUNDAY.
OUR SENSIBLE WEATHER HIGHLIGHTS INCLUDE ANOTHER CAD EVENT FOR THE
WEEKEND POSSIBLY ENHANCED AND PROLONGED BY THE MID/UPPER TROUGH THAT
IS EXPECTED TO PUSH INTO THE APPALACHIANS BY LATER SATURDAY... THEN
CROSS THE REGION SUNDAY. EXPECT PLENTY OF CLOUDS FRIDAY... THEN
OVERCAST CONDITIONS SAT-SUN WITH A GOOD CHANCE OF RAIN. TEMPS LIKELY
COLDER THAN GUIDANCE BY 5-7 DEGREES DURING THE DAY SAT AND SUN
YIELDING MOSTLY MID 40S TO MID 50S NW TO S.
BY MON-WED... THE SYSTEM IS EXPECTED TO PUSH OFFSHORE BY EARLY
MONDAY ALLOWING FOR CLEARING WITH A BIT MILDER TEMPERATURES BACK
INTO THE MID 50S TO LOWER 60S EARLY NEXT WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1255 PM WEDNESDAY...
SUB-VFR CONDITIONS CONTINUING ACROSS CENTRAL NORTH CAROLINA DURING
THE EARLY AFTERNOON SHOULD SLOWLY SHOW IMPROVEMENT...WITH MOSTLY VFR
CONDITIONS EXPECTED BY SUNSET. CONFIDENCE IS NOT REALLY HIGH AS SOME
OF THE MODEL SOUNDINGS SUGGEST CONTINUED MOISTURE SUCH THAT MVFR
CEILINGS COULD CONTINUE. HRRR WRF GUIDANCE CONTINUES TO FAVOR
GRADUAL EROSION OF THE LOWER CLOUDS THIS AFTERNOON. SHOULD THAT
HAPPEN...DURING THE NIGHT WITH DEW POINTS REMAINING HIGH AS LEAST
THROUGH THE EVENING WITH A LIGHT WIND...ANTICIPATE SOME AREAS OF FOG
WITH LOW CEILINGS SUCH THAT PERIODS OF SUB-VFR CONDITIONS SHOULD
OCCUR...HIGHEST PROBABILITY AND LONGEST LASTING TOWARD KFAY WHERE
THE LOW-LEVEL MOISTURE WILL BE HIGHEST. AS THE SURFACE FRONT MOVES
FARTHER SOUTH OF CENTRAL NORTH CAROLINA OVERNIGHT...ENOUGH DRY AIR
SHOULD PUSH FAR ENOUGH SOUTH THAT ALL OF CENTRAL NORTH CAROLINA WILL
BE PREVAILING VFR FOR THURSDAY MORNING. SOUTHWEST AND WEST SURFACE
WINDS GRADUALLY VEER WITH A WIDESPREAD NORTHEAST FLOW EXPECTED BY
12Z THURSDAY.
BEYOND THE 18Z VALID TAF PERIOD...A SERIES OF UPPER-LEVEL
DISTURBANCES WILL MOVE THROUGH OR NEAR CENTRAL NORTH CAROLINA
THURSDAY INTO FRIDAY. THERE IS A CHANCE OF SUB-VFR CONDITIONS... IF
IT OCCURS LIKELY MVFR CEILINGS...THURSDAY NIGHT INTO FRIDAY WITH A
FEW SPRINKLES OR A PASSING PATCH OF LIGHT RAIN MAINLY TOWARD KINT
AND KGSO. THE BETTER CHANCE OF SUB-VFR CONDITIONS AND AREAS OF RAIN
COMES OVERNIGHT FRIDAY INTO SATURDAY WITH THE MORE ADVERSE AVIATION
CONDITIONS EXPECTED TOWARD THE TRIAD AND KRDU. VFR CONDITIONS SHOULD
DEVELOP BEHIND A COLD FRONT SATURDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/VINCENT
SHORT TERM...VINCENT
LONG TERM...PWB
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
327 PM CST WED DEC 3 2014
.DISCUSSION...
OVERALL...A CLOUDY AND UNSETTLED WEATHER PATTERN CAN BE EXPECTED
OVER THE NEXT 7 DAYS. WE MAY NOT SEE ANY APPRECIABLE SUNSHINE AGAIN
UNTIL TUESDAY OF NEXT WEEK.
CURRENTLY...LATEST RADAR IMAGERY SHOWING SHOWER ACTIVITY UPSTREAM
OVER AR. THIS PRECIP IS IN ASSOCIATION WITH AN UPPER LEVEL IMPULSE
WHICH WILL BE MOVING ACROSS THE AREA TONIGHT AND INTO THURSDAY.
MODELS IN AGREEMENTS WITH SHOWING ENHANCED MOISTURE DEPTH TOWARD 12Z
WITH THIS IMPULSE. HRRR FURTHER CONCURS...BUT RAINFALL LOOKS MORE
PATCHY AND NOT WIDESPREAD. WILL THEREFORE GO A LITTLE ABOVE GUIDANCE
FOR TONIGHT AND THURSDAY.
THEN...ON FRIDAY...A STRONGER STORM SYSTEM WILL PULL EAST OUT OF THE
PLAINS AND BRING ADDITIONAL MOISTURE NORTHWARD OUT AHEAD OF IT.
LIKELY TO CATEGORICAL RAINFALL CHANCES WILL RETURN FOR FRIDAY AND
ESPECIALLY FRIDAY NIGHT.
FOR THE NEAR TERM TEMPS...OVERNIGHT LOWS WILL REMAIN ON THE MILD
SIDE. TEMPS ON FRIDAY WILL WARM INTO THE 60S AS THE SOUTHERLY
RETURN FLOW INCREASES.
IN THE EXT FCST...THE FRONTAL BOUNDARY IN ASSOCIATION WITH THE
AFOREMENTIONED STORM SYSTEM WILL MOVE THROUGH THE MID STATE EARLY
SATURDAY. SOME POST FRONTAL MOISTURE WILL KEEP SHOWER CHANCES GOING
THROUGH THE DAY. A BRIEF RESPITE FROM THE RAIN CHANCES WILL BE IN
PLAY ON SUNDAY AND MONDAY. THEN...THE EURO MODEL SHOWS A CLOSED
UPPER LEVEL LOW DIVING SE AND TAKING A TRACK TO THE SOUTH OF THE MID
STATE. ASSOCIATED 850 MB TEMPS SUPPORT SNOW. HOWEVER...THE GFS IS
DRY AND CONSALL TEMPS ARE WARMER. THUS...WILL OPT TO INCLUDE LOW
CHANCES FOR RAIN SHOWERS FOR MON TN AND TUES. IT DOES LOOK AS THOUGH
SOME SUNSHINE WILL RETURN BY TUESDAY OR WEDNESDAY OF NEXT WEEK.
FOR THE EXT TEMPS...PREVAILING AIRMASS BEHIND THIS WEEKENDS STORM
SYSTEM DOES NOT LOOK ALL THAT COLD. OVERALL...ABOVE NORMAL TEMPS ARE
EXPECTED TO CONTINUE.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 40 54 51 67 / 30 50 40 70
CLARKSVILLE 37 50 48 67 / 40 50 40 70
CROSSVILLE 39 55 50 61 / 30 50 40 60
COLUMBIA 42 58 52 68 / 30 40 40 60
LAWRENCEBURG 42 61 53 68 / 30 30 40 60
WAVERLY 39 53 49 68 / 30 50 40 70
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1116 AM CST WED DEC 3 2014
.UPDATE...
TEMPS ROSE QUICKLY THIS MORNING ACROSS THE CENTRAL AND SOUTHERN
SOUTH PLAINS...WITH LUBBOCK REACHING 61 DEGREES AT 11 AM. THIS WAS
DUE TO THE SLIGHTLY SLOWER PROGRESSION OF THE COLD FRONT MOVING
SOUTH OUT OF THE PANHANDLES. THE FRONT IS NOW MOVING THROUGH
THE CENTRAL SOUTH PLAINS AND SHOULD CLEAR OUR SRN ZONES BEFORE
STALLING OUT THIS AFTERNOON. WE UPPED HIGH TEMPS ACROSS OUR
SRN AREAS...AND TRIMMED THEM BACK SLIGHTLY ACROSS THE EAST WHERE
THICK CLOUD COVER HAS LIMITED HEATING.
&&
.AVIATION...
LOW STRATUS ADVANCING WESTWARD BEHIND A COLD FRONT MAY PRODUCE
MVFR TO IFR CEILINGS AT KCDS AS EARLY AS 18 UTC. KLBB AND KPVW
SHOULD REMAIN VFR TODAY. TONIGHT...EXPANDING COVERAGE OF LOW STRATUS
AND FOG WILL BRING A STRONG CHANCE OF IFR CONDITIONS TO ALL THE
TERMINALS WITH A POSSIBLE PERIOD OF LIFR AS WELL EARLY THURSDAY
MORNING. THE CEILING AND VSBY REDUCTIONS WILL LIKELY LAST THROUGH
17 OR 18 UTC THURSDAY. NORTH TO NORTHEAST SURFACE WINDS TODAY WILL
BECOME LIGHT AND VARIABLE TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 549 AM CST WED DEC 3 2014/
AVIATION...
SUB-TROPICAL HIGH CLOUD SHIELD SHOULD CONTINUE THROUGH MUCH OF THE
COMING 24 HOURS. WEAK COLD FRONT WILL SHIFT SOUTHWARD MID TO LATE
MORNING WITH AN MVFR CLOUD LAYER EXPECTED TO DEVELOP AT KCDS BY
EARLY THIS EVENING AND PERSIST WELL INTO OR THROUGH THE NIGHT.
ALSO POSSIBLE FOR AT LEAST MVFR VISIBILITY RESTRICTIONS TO DEVELOP
AT KCDS MAINLY LATER TODAY OR TONIGHT WITH LESSER CHANCES AT BOTH
KPVW AND KLBB LATER TONIGHT AS WELL. WE HAVE REMOVED THE PREVIOUS
TEMPO AT KCDS FOR LIGHT VISIBILITY RESTRICTIONS LASTING UNTIL 14Z
THIS MORNING AS DEW-POINT DEPRESSIONS HAVE NOT SIGNIFICANTLY
CLOSED WHILE THE HRRR TRENDS HAVE BACKED OFF GRADUALLY ON AREAL
COVERAGE OF REDUCED VISIBILITY THIS MORNING. WE WILL CONTINUE TO
REASSESS VISIBILITY ISSUES FOR LATER FORECASTS. RMCQUEEN
PREV DISCUSSION... /ISSUED 358 AM CST WED DEC 3 2014/
SHORT TERM...
A FLAT UPPER RIDGE WILL GRADUALLY MOVE OVERHEAD TODAY AND OFF TO THE
EAST ON THURSDAY WITH AN ABUNDANT SUBTROPICAL MOISTURE PLUME IN THE
MID AND UPPER LEVELS THIS MORNING...PERHAPS THINNING OR CLEARING
BRIEFLY AT TIMES TODAY...BEFORE THICKENING AGAIN TONIGHT. A MODEST
MOUNTAIN WAVE APPEARS LIKELY TO REMAIN A PLAYER IN HIGH CLOUD
COVER THOUGH MAY WEAKEN OR RELEASE BRIEFLY BEHIND A PASSING WAVE
LATER THIS MORNING. AT THE SURFACE...WE EXPECT A WEAKENING COLD
FRONT TO SAG THROUGH THE AREA LATER THIS MORNING BRINGING A 180
DEGREE WIND SHIFT. HIGHER DEW-POINTS SURGING NORTH THROUGH THE
ROLLING PLAINS MAY LEAD TO PATCHY FOG THIS MORNING...AND WE EXPECT
MOISTENING TO WORK UP ONTO THE CAPROCK AS WELL BY LATER TODAY. WE
HAVE ADDED A MENTION OF PATCHY FOG TONIGHT AND EXPANDED A BIT ONTO
THE CAPROCK. PRIOR TO PASSAGE OF THE COLD FRONT...THERE MAY BE
ENOUGH DOWNSLOPE COMPONENT THROUGH MID MORNING FOR A QUICK WARM-UP
ACROSS SOUTHERN COUNTIES DEPENDING ON IF HIGH CLOUDS THIN OR NOT.
TEMPERATURE GUIDANCE TODAY HAS BOUNCED AROUND CONSIDERABLY AS
SOLUTIONS HAVE STRUGGLED TO LATCH ONTO ABOVE FEATURES...THOUGH WE
HAVE SOME FAVORITISM TOWARDS THE LATEST TRENDS BEING WARMER THAN
PREVIOUS. IN SPITE OF RELATIVELY LOW CONFIDENCE WITH SEVERAL
SENSIBLE ELEMENTS TODAY...WE EXPECT BENIGN CONDITIONS TO DOMINATE
OVER-ALL. RMCQUEEN
LONG TERM...
A PROGRESSIVE SOUTHERN STREAM WILL BRING MULTIPLE CHANCES FOR
SHOWERS THROUGH THE NEXT SEVEN DAYS...ALBEIT NONE OF THEM APPEARING
TO BE TERRIBLY IMPRESSIVE AT THIS JUNCTURE...WHILE MAINTAINING A
FAIRLY STEADY STATE AIRMASS ACROSS THE REGION.
THE FIRST OF THESE DISTURBANCES IS SET TO SLIDE ACROSS THE TEXAS AND
OKLAHOMA PANHANDLES THURSDAY EVENING. THE LATEST TRENDS HAVE
CONTINUED TO SUGGEST A DAMPENING OF THIS IMPULSE...BUT MOISTURE
RETURN WILL BE UNDERWAY BY THURSDAY MORNING...WITH NORTHBOUND MOVING
STRATUS AND PATCHY FOG...AS TOP-DOWN MOISTENING TAKES PLACE
DOWNSTREAM OF THE APPROACHING SYSTEM. HOWEVER...A DRY POCKET BELOW
ABOUT H70 MAY PROVE TO BE A MITIGATING FACTOR IN PRECIPITATION
REACHING THE GROUND...THUS ALLOWING FOR ONLY VIRGA SHOWERS. WILL
CONTINUE TO MONITOR THE STRENGTH OF THIS SYSTEM AS IT HEADS ASHORE
THE PACIFIC COAST TONIGHT...BUT FEEL SLIGHT CHANCE POPS ARE STILL
WARRANTED NEAR THE NEW MEXICO STATE LINE BY LATE THURSDAY AFTERNOON
SPREADING EAST THURSDAY EVENING/EARLY NIGHT WITH INCREASING
MOISTURE/OMEGA PROFILES.
INCREASING HEIGHTS AND DOWNSLOPE WINDS SHOULD LEAD TO A NOTICEABLE
WARMUP WELL INTO THE 60S FRIDAY DESPITE A WEAK FRONT/NORTHERLY WIND
SHIFT SET TO MOVE THROUGH WEST TEXAS. THIS FRONT WILL HALT THE
WARMUP...SENDING TEMPERATURES BACK DOWN CLOSER TO AVERAGE IN THE
MID-UPPER 50S BEGINNING SATURDAY AND LASTING INTO NEXT WEEK. AT THE
SAME TIME...THE NEXT UPPER TROUGH WILL ENTER THE DESERT SOUTHWEST
AND BRING A RETURN TO CYCLONIC FLOW SATURDAY AFTERNOON. THIS SYSTEM
TOO HAS CONSISTENTLY SHOWN A WEAKENING TREND...NOW EXHIBITING A
POSITIVE TILT AND PERHAPS SUGGESTING THE BEST CHANCES FOR RAIN TO
RESIDE ACROSS THE SOUTHERN SOUTH PLAINS INTO THE SOUTHERN ROLLING
PLAINS SATURDAY EVENING INTO SUNDAY. EXACTLY HOW FAR SOUTH FRIDAY/S
FRONT PUSHES SOUTH MAY BE A LARGE DETERMINING FACTOR IN LOCAL
PRECIPITATION CHANCES AS THIS WILL AFFECT THE DEGREE/SPEED OF RETURN
FLOW AND GULF MOISTURE.
MONDAY LOOKS TO BRING ANOTHER DRY FRONTAL PASSAGE WITH UPPER RIDGING
IN VICINITY OF THE REGION AND ANOTHER POTENTIALLY LOOMING TROUGH
DEVELOPING UPSTREAM. HAVE KEPT LOW END POPS IN PLACE FOR MONDAY
EVENING INTO TUESDAY AT THIS TIME...BUT SIMILAR CONCERNS TO THE
WEEKEND/S SYSTEM MAY COME TO FRUITION WITH THE ECMWF NOW SHOWING
THIS SYSTEM DEVELOPING AND TRACKING MUCH FARTHER TO OUR SOUTH AND
WEST BEHIND AN IMPRESSIVE EASTERN CONUS UPPER LOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 51 35 61 39 62 / 0 0 20 20 10
TULIA 51 32 60 42 62 / 0 10 20 20 10
PLAINVIEW 54 35 59 42 64 / 0 0 10 20 10
LEVELLAND 63 36 59 43 67 / 0 0 10 20 10
LUBBOCK 62 35 60 45 67 / 0 0 10 20 10
DENVER CITY 66 38 61 43 69 / 0 0 10 20 10
BROWNFIELD 64 36 60 44 68 / 0 0 10 20 10
CHILDRESS 51 36 60 47 67 / 0 10 10 20 10
SPUR 62 35 59 47 69 / 0 0 10 20 10
ASPERMONT 62 39 62 51 71 / 0 10 10 20 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33