Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/21/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1023 AM MST WED FEB 19 2014
.UPDATE...NO MAJOR UPDATES AT THIS TIME...THE LATEST RUC AND HRRR
MDLS STILL APPEAR TO BRING THE SNOW IN THE MOUNTAIN AREAS THIS
AFTERNOON. LATEST MTR OBS INDICATED SNOW AT OVER NRN UT AND SWRN
WY...WITH CIGS BKN-OVC090-100 AGL AT CRAIG AND MEEKER SO STILL
FAIRLY HIGH. CURRENT FORCAST OF DEVELOPING THIS AFTN STILL LOOKS
ON TRACK.
&&
.AVIATION...NOT MUCH CHANGE IN THE TAFS FM THE PRVS DISCUSSION.
VFR CIGS/VSBYS THROUGH 02Z THIS EVENING. CIGS LOWERING TO BLO 5KT
AFTER 03Z STILL LOOKS REASONABLE. RAIN OR RAIN/SNOW MIX POSSIBLE
THROUGH 06-07Z THEN IT SHUD TURN OVER THE SNOW. STILL ANTICIPATE
A SHORT LIVED PRECIPITATION EVENT WITH LITTLE IF ANY SNOWFALL
ACCUMULATION. BEST CHC OF SNOW WILL BE EAST OF THE DENVER AREA.
OVERALL TREND IN THE WIND FORECAST STILL LOOKS OKAY...WITH THE
STRONGEST WINDS FOLLOWING FROPA.
&&
.PREV DISCUSSION... /ISSUED 416 AM MST WED FEB 19 2014/
SHORT TERM...EXPECTING TODAY TO BE ANOTHER MILD ONE AS WE WILL BE
UNDER THE SOUTHWESTERLY FLOW AHEAD OF TONIGHTS APPROACHING UPPER
TROUGH. THE FLOW PATTERN IS VERY PROGRESSIVE...MOVING THE UPPER
LEVEL DISTURBANCE ACROSS THE STATE IN ABOUT 12 HOURS. QUASI-
GEOSTROPHIC DIAGNOSTICS PACKAGE SHOWS THE SYSTEM WILL HAVE QUITE A
BIT OF FORCING AS IT MOVES THROUGH...WHICH SHOULD DELIVER A PRETTY
GOOD SHOT OF SNOW TO THE MOUNTAIN AREAS. INTERACTION WITH THE
TERRAIN OF THE FRONT RANGE WILL LEAVE A MINIMUM IN PRECIPITATION
IN THE LEE OF THE FOOTHILLS...BUT PRECIPITATION COVERAGE SHOULD
THEN INCREASE AGAIN AS THE SYSTEM PROGRESSES EASTWARD. WILL
CONTINUE THE WINTER WEATHER ADVISORY IN THE MOUNTAINS FOR 4 TO 8
INCHES OF NEW SNOW...AND THE CHANCE POPS OR GREATER ON THE PLAINS
OVERNIGHT. TEMPERATURES ALONG THE I-25 CORRIDOR MAY BE WARM ENOUGH
EARLY IN THE EVENING THAT PRECIPITATION WILL BEGIN AS RAIN AND
THEN TRANSITION TO SNOW BY LATE EVENING. SURFACE COLD FRONT WILL
MOVE SOUTHWARD FROM THE WYOMING BORDER STARTING AROUND 00Z AND
THEN MOVE THROUGH DENVER BY 03Z. AS THE DISTURBANCE MOVES RAPIDLY
ACROSS THE COUNTY WARNING AREA...MOST PRECIPITATION ON THE PLAINS
SHOULD BE COMING TO AN END BY SUNRISE THURSDAY MORNING. MOUNTAINS
MAY STILL SEE SOME LINGERING SHOWERS AS MOISTURE GETS CAUGHT WEST
OF THE CONTINENTAL DIVIDE AND NORTHWEST FLOW HELPS PRODUCE
OROGRAPHIC SHOWERS.
LONG TERM...THE UPPER LEVEL TROUGH WILL BE EAST OF THE AREA THU
MORNING WITH FAIRLY STG NW FLOW ALOFT CONTINUING THRU THE AFTN.
CROSS-SECTIONS STILL SHOW DECENT MOISTURE IN THE MTNS IN THE
MORNING WITH FAVORABLE OROGRAPHICS SO MAY SEE ANOTHER FEW INCHES
OF SNOW WITH GUSTY WINDS AS WELL SO MAY NEED TO EXTEND ADVISORY
THRU THE LATE MORNING HOURS. OVER NERN CO IT WILL BE DRY BUT GUSTY
NW WINDS WILL OCCUR. BNDRY LAYER WINDS ARE STILL FCST IN THE 40-45
KT RANGE SO MAY SEE GUSTS UP TO 50 MPH AT TIMES. AT THIS TIME WILL
NOT ISSUE A HIGH WIND WATCH AS BELIEVE SPEEDS WILL STAY JUST BLO
WARNING CRITERIA. AS FOR HIGHS DECENT CAA IS FCST OVER THE AREA SO
WILL KEEP READINGS MAINLY IN THE UPPER 30S TO LOWER 40S.
FOR THU NIGHT AND FRI NWLY FLOW ALOFT WILL REMAIN OVER THE AREA AS A
FEW WK DISTURBANCES MOVE THRU IN THE FLOW. GFS CROSS-SECTIONS SHOW
MOISTURE DEPTH INCREASING IN THE MTNS THU EVENING AND CONTINUING
THRU FRI WITH FAVORABLE OROGRAPHICS. LAPSE RATES ARE INITIALLY IN
THE 5-6 C/KM RANGE HOWEVER THEY IMPROVE TO AROUND 7 C/KM BY AFTN.
IN ADDITION THERE WILL BE AN UPPER LEVEL JET OVERHEAD SO MAY SEE
SOME ENHANCEMENT OF SNOWFALL RATES FROM TIME TO TIME. MEANWHILE
ECMWF HAS LESS MOISTURE FOR THE SAME PERIOD WITH OVERALL SNOWFALL
AMOUNTS MUCH LIGHTER. THUS WILL HOLD OFF ON A WSA AND LET THE DAY
SHIFT SEE IF THE ECMWF AND GFS COME INTO BETTER AGREEMENT. AT LOWER
ELEVATIONS IT WILL REMAIN DRY HOWEVER THERE WILL BE A POTENTIAL FOR
HIGH WINDS THU NIGHT INTO FRI MORNING IN AND NR THE FOOTHILLS.
CROSS MTN FLOW INCREASES TO 60-70 KT THU NIGHT WITH SOME HINT OF A
MTN WAVE. HOWEVER AS WE HAVE SEEN THE LAST SEVERAL EVENTS THE
STRONGER WIND GUSTS HAVE BEEN RATHER SPORADIC AND NOT THAT
WIDESPREAD SO WE SHALL SEE HOW THIS EVENT UNFOLDS. AS FOR HIGHS ON
FRI WITH SOME WARMING IS SHOWN IN THE 850-700 MB LAYER SO WILL
TWEAK HIGHS INTO THE 45 TO 50 DEGREE RANGE OVER NERN CO.
BY FRI NIGHT AND SAT THERE IS LITTLE CHANGE TO THE OVERALL PTRN AS
THE FLOW ALOFT REMAINS NWLY. BOTH THE ECMWF AND GFS SHOW VARYING
AMOUNTS OF MOISTURE AFFECTING THE MTNS HOWEVER LAPSE RATES ARE AOA 7
C/KM SO IF MOISTURE DEPTH REMAINS FAVORABLE CERTAINLY COULD SEE
DECENT ACUMULATIONS IN SOME AREAS. AT LOWER ELEVATIONS IT APPEARS A
CDFNT WILL MOVE INTO NERN CO BY MIDDAY WITH SOME UPSLOPE FLOW LATE
SAT AFTN INTO SAT NIGHT. BOTH THE ECMWF AND GFS DO SHOW SOME
POTENTIAL FOR PCPN OVER NERN CO AS UPPER LEVEL JET IS OVERHEAD AND
MOISTURE IMPROVES BY EVENING THUS WILL KEEP IN POPS FOR SAT NIGHT.
HIGHS ON SAT OVER THE PLAINS WILL DEPEND ON HOW FAST FNT MOVES IN.
READINGS MAY STAY IN THE LOWER TO MID 30S NR THE WY-NE BORDER WHILE
FURTHER SOUTH HIGHS REACH THE LOWER 40S BEFORE THE FNT ARRIVES.
ON SUN THE FLOW ALOFT WILL REMAIN NWLY HOWEVER BOTH THE ECMWF AND
GFS SHOW MOISTURE DECREASING IN THE MTNS SO SNOW CHANCES SHOULD
DIMINISH. OVER NERN CO THE MAIN PUSH OF COLD AIR MAY STAY
GENERALLY TO THE EAST OF THE AREA SO WILL KEEP HIGHS MAINLY IN THE
UPPER 30S TO LOWER 40S.
FOR EARLY NEXT WEEK A BROAD UPPER LEVEL TROUGH WILL EXTEND FM THE
NRN PLAINS ACROSS THE GREAT LAKES WITH NRN CO BASICALLY STAYING IN
WNW FLOW ALOFT THRU TUE. THERE ARE LIKELY GOING TO BE SOME SURGES
OF SHALLOW COLDER AIR MOVING INTO NERN CO IN THIS TYPE OF PATTERN.
BOTH THE ECMWF AND GFS SHOW ONE DECENT SURGE COMING IN ON MON WHICH
COULD LEAD TO A CHC OF SOME LIGHT PCPN IF ENOUGH MOISTURE IS
AVAILABLE OVER NERN CO. HIGH TEMPS WILL BE A PROBLEM DEPENDING ON
TIMING OF THIS SURGE AS READINGS COULD STAY IN THE 30S IF IT ARRIVES
BY MORNING. IN THE MTNS BOTH THE ECMWF AND GFS KEEP THE BEST
MOISTURE OVER WY AT THIS TIME SO WILL ONLY MENTION SOME LOW POPS FOR
NOW.
AVIATION...AVIATION IMPACTS SHOULD BE MINIMAL THROUGH THE EARLY
EVENING. WINDS SHOULD TREND TOWARD SOUTHWESTERLY AND WESTERLY
THROUGH THE DAY...AHEAD OF THIS EVENINGS COLD FRONT. EVEN BEHIND
THE FRONT...WINDS SHOULD REMAIN OUT OF THE NORTHWEST AS THE UPPER
DISTURBANCE TRACKS ACROSS THE REGION QUICKLY. DOWNSLOPING WINDS
OVERNIGHT SHOULD HELP KEEP CEILINGS A LITTLE HIGHER...BUT CAN NOT
RULE OUT CEILINGS DROPPING BELOW 5000 FEET AGL FOR A FEW HOURS.
PRECIPITATION THAT FALLS MAY BE A MIX OF RAIN AND SNOW BEFORE 06Z.
AFTER 06Z...TEMPERATURES WILL BE COLD ENOUGH THAT ANY LINGERING
SHOWERS WILL BE IN THE FORM OF SNOW. SNOW ACCUMULATIONS SHOULD BE
MINIMAL SINCE THE SYSTEM WILL BE MOVING THROUGH SO QUICKLY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 5 AM MST
THURSDAY FOR COZ031-033-034.
&&
$$
SHORT TERM...COOPER
LONG TERM....99
AVIATION...99
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1019 PM EST THU FEB 20 2014
.SYNOPSIS...
A WARM FRONT BRINGS A WINTRY MIX OF PRECIPITATION TO OUR REGION
TONIGHT INTO FRI MORNING ACROSS THE INTERIOR...WITH RAIN
ELSEWHERE. MUCH WARMER AIR THEN INVADES CONNECTICUT...RHODE
ISLAND AND MUCH OF MASSACHUSETTS FRIDAY AFTERNOON ALONG WITH GUSTY
SHOWERS AND LOCALLY HEAVY RAINFALL. A COOLING TREND FOLLOWS FOR
THIS WEEKEND...WITH MUCH COLDER WEATHER LIKELY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
1015 PM UPDATE...MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES
AND TO THE TIMING OF THE PRECIPITATION. HAVE RECEIVED NUMEROUS
REPORTS OF SLEET FROM ACROSS SOUTHERN NEW ENGLAND AND THE
ADJUSTMENTS TO TEMPERATURES HAVE ALLOWED THE FORECAST TO BETTER
REFLECT WHAT IS GOING ON. USED THE HRRR FOR THE POPS AS IT IS
REFLECTING THE TRENDS BEST. TEMPERATURES ARE RIGHT AROUND FREEZING
TO THE MID 30S. EXPECT TEMPERATURES TO WARM A BIT FROM THE SOUTH
AS WINDS TURN TO THE SOUTH LATER ON TONIGHT. TEMPS ARE IN THE MID
40S AS CLOSE AS NJ.
PREVIOUS DISCUSSION...
A COUPLE OF FORECAST CONCERNS FOR THIS EVENING WHICH INCLUDE A
WINTRY MIX OF SNOW/SLEET/FREEZING RAIN OVER THE INTERIOR...AND THE
POTENTIAL FOR DENSE FOG.
BRIEFLY...DEEP LOW UNDERGOING OCCLUSION OVER THE GREAT LAKES REGION
WILL RESULT IN HEIGHT FALLS AND INCREASING S/SW FLOW ALOFT. LEADING
EDGE ALONG A MID-LEVEL WARM FRONT /PRESENTLY OVER PA-UPSTATE NY/
WILL BE THE FOCUS FOR PRECIP ACROSS THE REGION AS IT SWEEPS ACROSS
THE NE CONUS ABOVE A SHALLOW COLD-AIRMASS OVER A DEEPER SNOW-PACK.
FOR THE WINTRY MIX...MUCH OF THE PRECIP WILL BE FOCUSED ALONG THE
MID-LEVEL WARM FRONT SWEEPING NORTH ACROSS THE REGION DURING THE
PERIOD. IT IS ALONG THE WARM-FRONT THAT THE COMBINATION OF F-GEN
BANDING/ISENTROPIC ASCENT/STEEP LAPSE-RATES ABOVE THE INVERSION
BENEATH BROADSCALE DIFFLUENCE WILL LEAD TO LIGHT PRECIP AMOUNTS.
EVALUATING NEAR-TERM MESOSCALE GUIDANCE...HAVE AN AVERAGE OF TWO-
TENTHS WITH THE HIGHEST AMOUNTS ANTICIPATED ALONG S/W SLOPES OF HIGH
TERRAIN WITH LOCALIZED CONVERGENCE AND OROGRAPHIC LIFT.
SUCH LIGHT PRECIP WILL OVERSPREAD SHALLOW COLD AIR RESULTING IN A
QUICK INITIAL BURST OF SNOW/SLEET BEFORE CHANGING OVER TO MAINLY
FREEZING RAIN. 2M TEMPS/DEWPOINTS CRITICAL IN EVALUATING THREATS BUT
A CHALLENGE TO NAIL DOWN AS EMPHASIZED BY THE PREV FORECASTER. AGAIN
USED NEAR-TERM MESOSCALE GUIDANCE WHILE INCORPORATING GREATER WEIGHT
TOWARDS THE WETBULB. ANTICIPATE FREEZING RAIN MAINLY OVER THE N/W
INTERIOR LINGERING TOWARDS MID-MORNING.
TAKING THESE OUTCOMES AND CONSIDERING IMPACT GUIDANCE BASED ON TOP
CIPS ANALOGS WHICH PLACES THE GREATEST CONFIDENCE OF THE FREEZING
RAIN THREAT AROUND AND NORTH OF THE MA/VT/NH BORDER...WILL KEEP WITH
THE PRESENT WINTER WEATHER ADVISORY HEADLINES.
AS FOR DENSE FOG...EVALUATING THE DEWPOINT DEPRESSION...EXPECTING
ONSHORE FLOW OF WARMER AIR TOWARDS MORNING OVER THE REMNANT SNOW-
PACK TO RESULT IN AREAS OF DENSE FOG WITH VISIBILITIES DOWN TO A
QUARTER MILE OR LESS POSSIBLE FOR THE SOUTH AND SOUTHEAST COASTLINE
INCLUDING ADJACENT COASTAL PLAINS TOWARDS THE MORNING...SPREADING
INTO THE INTERIOR THEREAFTER. SOME UNCERTAINTY ON THE TIMING OF
WARMER AIR WITH PERHAPS THE SURFACE WARM-FRONT HANGING UP ON THE
SOUTH-COAST LENDS TO LESSER CONFIDENCE TOWARDS ISSUING A DENSE FOG
ADVISORY. WILL HIGHLIGHT THE THREAT IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY TOWARDS MIDNIGHT SATURDAY...
WARMER AIR PUSHING UP FROM THE SOUTH WILL ERODE THE WINTRY MIX OVER
THE N/W INTERIOR INTO MID-MORNING. BUT THIS WILL LIKELY RESULT IN
AREAS OF FOG DEVELOPING ACROSS THE INTERIOR WITH VISIBILITIES DOWN
TO A QUARTER MILE OR LESS POSSIBLE.
OTHERWISE MAIN FOCUS WILL BE UPON THE ATTENDANT COLD FRONT TO THE
OCCLUDING LOW SWEEPING THROUGH THE REGION INTO EVENING. MAIN
CONCERNS FOCUS ON POTENTIAL THREATS OF WIND/FLOODING/THUNDERSTORMS
WHICH ARE OUTLINED BELOW.
WITH REGARDS TO WIND...STRONG S/SW FLOW DEVELOPING ALONG AND AHEAD
OF THE COLD FRONT WITH NEAR 70 MPH WINDS AT H925 BY AFTERNOON ABOVE
THE CONTINUED STOUT INVERSION /DISTINCT WARM-NOSE AROUND H9/. NEAR
40 MPH GUSTS AT THE SURFACE ANTICIPATED PER PRES-GRADIENT...BUT FEEL
SHALLOW COLD-AIR AND STOUT INVERSION ALOFT WILL LIMIT MIXING. FEEL
ANYTHING HIGHER PERHAPS WITH ANTICIPATED CONVECTION /PRECIP DRAG AND
MECHANICAL-MIXING PROCESSES/ CAN BE HANDLED WITH SHORT-FUSED
WARNINGS...THUS WILL NOT ISSUE A WIND ADVISORY WITH THIS FORECAST
PACKAGE.
AS TO POTENTIAL FLOODING...FURTHER DISCUSSION IS PROVIDED IN THE
HYDROLOGY DISCUSSION BELOW. ALBEIT A ROUGHLY 3 STANDARD DEVIATION
PWAT AXIS INTO SNE OF 1-1.5...THE QUICK MOVING FRONT PRODUCES AN
AREA-WIDE AVERAGE PRECIP AMOUNT OF HALF AN INCH. LOCALLY HIGHER
AMOUNTS ANTICIPATED /ESPECIALLY WITH CONVECTION/. WILL NOT GO WITH A
FLOOD WATCH...RATHER HANDLE ANY FLOODING ISSUES WITH SHORT-FUSED
PRODUCTS. FEEL THE BULK OF THE FLOODING WILL BE NUISANCE/POOR-
DRAINAGE WITH SNOW-CLOGGED STORM DRAINS.
LASTLY POTENTIAL THUNDERSTORMS...ALL CONVECTIVE INDICES MEET OR
EXCEED THRESHOLDS ALONG AND AHEAD OF THE COLD FRONT TO CONSIDER
THUNDERSTORMS IN THE FORECAST. GREATEST CONFIDENCE IS FOR S/SE
PORTIONS OF THE FORECAST AREA IN REGIONS OF GREATER MUCAPE. HAVE
GONE AHEAD WITH AN ISOLATED MENTION FOR NOW MAINLY FOCUSED ON THE
MIDDAY INTO EVENING HOURS.
MIDNIGHT SATURDAY INTO SATURDAY MORNING...
DRY AIR WRAPPING IN REARWARD OF THE DEPARTING SYSTEM. BUT WITH LOW
UNDERGOING OCCLUSION...AIR IS NOT EXCEPTIONALLY COLD ESPECIALLY WITH
THE SOUTHWESTERLY COMPONENT OF FLOW. THOUGH A DRY-AIR INVERSION
BUILDING ACROSS THE REGION WITH GROWING INFLUENCE OF HIGH-PRES...THE
ANOMALOUS DEEP-NATURE OF THE LOW WILL LIKELY LEND TO SOME BLUSTERY
SOUTHWEST WINDS. LOWS DOWN TO AROUND THE UPPER-20S WITH PERHAPS SOME
HIGH CLOUDS WRAPPING REAR-WARD BEHIND THE DEEP-LOW.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
* MILD THIS WEEKEND...FOLLOWED BY A GRADUAL COOLING TREND
* A RETURN TO COLDER THAN NORMAL CONDITIONS NEXT WEEK
THIS WEEKEND...LOW PRESSURE REMAINS PARKED OVER JAMES BAY IN
CANADA. THIS LOW PRESSURE WILL SWEEP ANOTHER COLD FRONT ACROSS
OUR REGION SUNDAY. SOME MEMBERS OF THE 20/12Z GUIDANCE
SUITE...NOTABLY THE GFS AND ECMWF...GENERATE A WEAK SURFACE WAVE
ALONG THIS FRONT JUST OFFSHORE SUNDAY NIGHT AS A POTENT MID-LEVEL
SHORTWAVE MOVES OVERHEAD. INCREASED POPS TO A SLIGHT CHANCE FOR
THIS TIME PERIOD. WILL NEED TO SEE BETTER CONSISTENCY...AND A
TRACK CLOSER TO THE COAST...BEFORE INCREASING POPS FURTHER. AT
THIS POINT...IT APPEARS TO BE SOME LIGHT SNOW SHOWERS AT WORST.
NEXT WEEK...CONTINENTAL POLAR AIRMASS BECOMES ENTRENCHED ACROSS
MUCH OF THE NORTHERN STATES/GREAT LAKES INTO THE NORTHEAST. STILL
MANY SIGNS OF A RETURN TO BELOW NORMAL TEMPERATURES. DEPENDING
UPON THE STRENGTH OF THIS COLD AIR...THE STORM TRACK MAY BE
SHIFTED WELL SOUTH OF OUR REGION. 20/12Z GUIDANCE CONTINUES TO
DEPICT ANOTHER COASTAL LOW PRESSURE MOVING OFF THE MID ATLANTIC
COAST IN THE TUESDAY/WEDNESDAY TIME FRAME. AT THIS POINT...IT
APPEARS OUR REGION WOULD BE ON THE FAR NORTHERN PERIPHERY OF THIS
STORM. WILL NEED TO CONTINUE TO MONITOR THE TRENDS OF THIS STORM
TRACK.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM FORECAST /THROUGH FRIDAY/...
VFR INTO EVENING. WILL SEE CONDITIONS DETERIORATE TOWARDS MORNING.
SCT RAPL THIS EVENING WITH INITIAL ONSET OF PRECIPITATION. MVFR-
LIFR WITH FZRA ACROSS THE N/W INTERIOR AND AREAS OF DENSE FOG
ADVECTING UP FROM THE SOUTH LATER TONIGHT. CONDITIONS TO REMAIN
LOW FRIDAY...WITH DENSE FOG SPREADING FARTHER NORTH INTO THE
INTERIOR. FZRA ENDS IN THE N/W INTERIOR BY MID-MORNING. A COLD
FRONT MOVES THROUGH THE TERMINALS DURING THE AFTERNOON AND
LATE EVENING HOURS. +RA/TSRA POSSIBLE AHEAD OF THIS FRONT...ALONG
WITH POCKETS OF LLWS /70 KT SLY FLOW 2 KFT AGL AROUND 21Z/.
CONDITIONS IMPROVE AFTER MIDNIGHT SATURDAY.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF TRENDS.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF TRENDS.
OUTLOOK...SATURDAY THROUGH TUESDAY...
VFR LIKELY. BRIEF MVFR POSSIBLE IN WIDELY SCATTERED SNOW/RAIN
SHOWERS SUNDAY NIGHT. WIDELY SCATTERED MVFR POSSIBLE IN SNOW
SHOWERS TUESDAY.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
WINDS AND SEAS MAY BE DIMINISHED PRESENTLY...BUT EXPECT DENSE FOG
TO DEVELOP OVER THE WATERS TOWARDS MORNING WITH VISIBILITIES DOWN
TO A QUARTER MILE OR LESS AS SOUTHERLY WINDS INCREASE TOWARDS NEAR
GALE FORCE BY MIDDAY INTO EVENING FRIDAY ALONG AND AHEAD OF A COLD
FRONT. SEAS TO BUILD 8 TO 10 FEET. THUNDERSTORMS POSSIBLE ALONG
AND AHEAD OF THE COLD FRONT IN ADDITION TO STRONG WINDS. ACTIVITY
COMES TO AN END AFTER MIDNIGHT SATURDAY.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SAT/SUN...MODEST SW WIND SAT THEN EASING SUNDAY AS HIGH PRES
BUILDS OVER THE WATERS. LINGERING ROUGH SEAS ACROSS THE OUTER
COASTAL WATERS GRADUALLY SUBSIDE.
MON/TUE...A WEAK LOW PRES TRACKS S OF NEW ENGLAND EARLY MON...
FOLLOWED BY A MODEST NW WIND MON NIGHT. WEAK HIGH PRES THEN BUILDS
ACROSS THE WATERS TUE. ROUGH SEAS OF 5-7 FEET LIKELY ACROSS THE
OUTER COASTAL WATERS.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS MOST OF SOUTHERN NEW ENGLAND RANGE FROM 1 TO
2 FEET...EXCEPT FOR SOMEWHAT LOWER AMOUNTS ALONG SOUTH COASTAL RI
AND MA. TEMPERATURES ARE FORECAST TO CLIMB GENERALLY INTO THE 40S
TO LOW 50S FRIDAY AND SATURDAY...AND OVERNIGHT LOWS WILL BE CLOSE
TO OR BELOW FREEZING. AS A RESULT SOME SNOWMELT WILL OCCUR DURING
THE DAYTIME...WITH THE MOST SNOWMELT EXPECTED ACROSS SOUTHEAST MA
AND SOUTHERN RI WHERE THE SNOWPACK IS THE MOST DENSE AND THE
WARMEST.
ACROSS THE REGION...BARRING THE FREEZING RAIN POTENTIAL FOR
TONIGHT...RAINFALL OF AROUND A HALF INCH IS EXPECTED TONIGHT INTO
FRIDAY. THIS WILL LIKELY CAUSE PONDING OF WATER IN LOCATIONS WHERE
THERE ARE SNOW CLOGGED DRAINS.
THE COMBINATION RAIN AND SNOWMELT ON FRIDAY WILL GIVE SOME AREA
SMALL STREAMS AND RIVERS A BOOST...AND THIS MAY PROMPT ICE MOVEMENT.
THERE IS A CHANCE OF ISOLATED ICE JAM DEVELOPMENT ON FRI FOR SMALL
STREAMS ACROSS CENTRAL INTO WESTERN MA AND NORTHERN CT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR MAZ002>005-
008>012-026.
NH...WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NHZ011-012-
015.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO 4 AM EST SATURDAY FOR
ANZ231>234-251.
SMALL CRAFT ADVISORY FROM 1 PM FRIDAY TO 1 AM EST SATURDAY FOR
ANZ236.
SMALL CRAFT ADVISORY FROM 10 AM FRIDAY TO 7 AM EST SATURDAY
FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ250-
254>256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...BELK/RLG/SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS ALBANY NY
1236 PM EST WED FEB 19 2014
.SYNOPSIS...
ANOTHER FAST MOVING LOW PRESSURE SYSTEM WITH ITS
ASSOCIATED WARM AND COLD FRONTAL BOUNDARIES WILL BRING A PERIOD OF
SNOW AND RAIN TO THE REGION THIS AFTERNOON AND EVENING. MILDER AIR
WILL THEN MOVE INTO THE REGION BY THE END OF THE WEEK...ALONG WITH A
CHANCE OF RAIN SHOWERS...AS A STRONG COLD FRONT APPROACHES FROM THE
GREAT LAKES THURSDAY NIGHT AND FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1235 PM...A BURST OF MODERATE TO HVY SNOWFALL HAS MOVED IN
ACROSS MOST OF ERN NY AND WRN NEW ENGLAND AHEAD OF A POTENT SHORT-
WAVE AND A WARM FRONT. SNOW RATES INCREASED TO 1-2"/HR AS A RESULT
OF THE RADAR RETURNS AND SOME GROUND TRUTH HAS SOME IN WITH SNOW
AMOUNTS UP TO 2" ALREADY IN RHINEBECK AND CATSKILL. SOME FREEZING
RAIN HAS ALSO BEEN REPORTED IN KPOU BASED ON THE ASOS. THE COLUMN
SHOULD COOL DOWN QUICKLY TO TRANSITION TO SNOW. AN SPS HAS BEEN
ISSUED TO TO COVER THE SNOW NORTH OF THE MID HUDSON RIVER
VALLEY...AND MENTION SOME FREEZING RAIN WITH A LIGHT ICE
ACCUMULATION FOR ERN ULSTER...DUTCHESS AND LITCHFIELD COUNTIES FOR
AN HOUR OR SO.
THE PCPN IS DUE TO STRONG ISENTROPIC LIFT AHEAD OF THE WARM
FRONT...AND THE STRONG UPWARD VERTICAL MOTION GENERATED BY THE
FRONT...AND THE SHORT-WAVE. SNOW AMOUNTS HAVE BEEN INCREASED TO
2-4 INCHES OVER SRN VT...THE BERKSHIRES...ERN CATSKILLS...GREENE
CTY...COLUMBIA CTY...PARTS OF THE SRN DACKS...AND THE LITCHFIELD HILLS.
EXPECT 1-2/1-3 INCHES IN MOST OTHER LOCATIONS.
THE LATEST RADAR TRENDS AND HRRR SHOWS THE BATCH OF SNOW AND MIXED
PCPN MOVING THROUGH BEFORE 3 PM ACROSS THE ENTIRE FCST AREA. THE
COLD FRONT WILL ARRIVE WITH ANOTHER ROUND OF RAIN TO SNOW SHOWERS
THIS EVENING.
CONTINUED MAX TEMPS...WITH MID/UPPER 30S IN VALLEY AREAS FROM
ALBANY SOUTH...AND GENERALLY LOWER/MID 30S TO THE NORTH...WITH
GENERALLY 20S TO LOWER 30S ACROSS HIGHER ELEVATIONS.
SOUTH TO SOUTHEAST WINDS WILL INCREASE INTO THE EARLY
AFTERNOON...SIMILAR TO YESTERDAY...WITH SOME GUSTS POSSIBLY
REACHING UP TO 30-35 MPH ACROSS PORTIONS OF SW VT...THE
BERKSHIRES...AND TACONICS...AND POSSIBLY UP TO 25-30 MPH WITHIN
THE CAPITAL REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...AS THE MAIN SHORTWAVE TROUGH PASSES THROUGH...ANOTHER
BURST OF PRECIPITATION IS EXPECTED. THE PRECIP SHOULD BE MORE
SHOWERY IN NATURE. IN FACT...MODEL SOUNDINGS ACTUALLY INDICATE RATHER
STEEP LAPSE RATES IN THE 700-500 HPA LAYER...WITH THE LATEST RAP13
INDICATING AS STEEP AS 8-8.5 C/KM. THESE STEEP LAPSE RATES...COMBINED
WITH ASCENT FROM THE APPROACHING/PASSING SHORTWAVE TROUGH...COULD
EVEN ALLOW FOR SOME ISOLATED THUNDERSTORMS ACROSS THE
REGION...SOME OF WHICH COULD PRODUCE GRAUPEL/SMALL HAIL. IN THE
WAKE OF THE TROUGH PASSAGE...STRONG WEST/NORTHWEST WINDS WILL
LIKELY DEVELOP...WITH ENHANCED FLOW DOWN THE MOHAWK RIVER
VALLEY/CAPITAL REGION AND BERKSHIRES EXPECTED. THIS COULD ALLOW
FOR SOME GUSTS TO REACH 35-40 MPH AT TIMES LATER THIS EVENING
UNTIL SHORTLY AFTER MIDNIGHT. SKIES SHOULD INITIALLY REMAIN MOSTLY
CLOUDY...BUT AS STRONG SUBSIDENCE AND SOME DOWNSLOPING
OCCURS...SKIES SHOULD TREND TO MOSTLY CLEAR WELL AFTER MIDNIGHT.
TEMPS WILL BE TRICKY...AS THERE COULD BE A WINDOW OF RAPID
DECOUPLING RIGHT AROUND OR EVEN AFTER DAYBREAK. HOWEVER...WIND AND
SOME CLOUDS SHOULD KEEP THIS FROM OCCURRING FOR MOST OF THE NIGHT.
SO...ALTHOUGH HAVE SIDED WITH THE COOLER MOS...DID NOT GO MUCH
COOLER. STILL EXPECT WIDESPREAD TEENS AND 20S ACROSS THE REGION.
THURSDAY...HIGH PRESSURE RIDGE WILL TRANSLATE EAST ACROSS THE
REGION. SKIES SHOULD BE MOSTLY SUNNY IN THE MORNING...WITH CLOUDS
INCREASING IN THE AFTERNOON. SOME LIGHT PRECIPITATION COULD REACH
FAR WESTERN AREAS TOWARD OR JUST AFTER SUNSET...MAINLY AS
RAIN...ALTHOUGH A RAIN/SLEET/SNOW MIX COULD OCCUR IN HIGHER
ELEVATIONS. EXPECT MAX TEMPS TO REACH THE UPPER 30S TO LOWER 40S
IN MOST VALLEY AREAS...AND LOWER/MID 30S FOR HIGHER ELEVATIONS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
AS POTENT STORM WRAPS UP ACROSS THE CENTRAL GREAT LAKES
REGION...EQUALLY IMPRESSIVE LOW LEVEL JET AND ISENTROPIC LIFT WILL
UNFOLD ACROSS UPSTATE NEW YORK THURSDAY NIGHT. THIS WILL ALLOW FOR
BANDS OF PRECIPITATION TO EVOLVE FROM SOUTH TO NORTH WITH THE PEAK
OF THE LOW LEVEL FORCING TAKING PLACE ACROSS THE ADIRONDACKS.
THERMAL PROFILES ACROSS THE REGION WILL BE TRANSITIONING WITHIN THE
WARM ADVECTION AS BOUNDARY LAYER TEMPS MAY STRUGGLE FOR A PERIOD OF
TIME. THIS SETS THE STAGE FOR SNOW MIXING WITH SLEET/FREEZING RAIN
IMPACTING MAINLY THE ADIRONDACKS AND SOUTHERN
GREENS...ALTHOUGH...COULD NOT RULE OUT SOME ISOLATED SHELTERED
LOCATIONS RECEIVING A WINTRY MIX IN THE MOHAWK AND CENTRAL-NORTHERN
HUDSON RIVER VALLEY. HOWEVER...THE STRENGTH OF THE WARM ADVECTION
WILL EVENTUALLY OVERCOME THE SHALLOW SUB FREEZING TEMPERATURES
FRIDAY MORNING FOR ALL OF THE PRECIPITATION TO BECOME RAIN.
ALONG WITH THE TEMPERATURES INCREASING...SO DOES THE DEWPOINT TO
ABOVE FREEZING. AS THIS WARMER AND MORE MOIST AIR ADVECTS OVER A
SNOW COVERED GROUND WOULD RESULT IN FOG AS WE WILL PLACE THIS IN THE
GRIDS. STRONG COLD FRONT WITH A FAIRLY TIGHT THERMAL GRADIENT FROM
+8C AT H850 OVER EASTERN NY TO -6C OVER WESTERN NY WILL QUICKLY MOVE
ACROSS THE REGION BY EARLY AFTERNOON PER THE LATEST NCEP MODEL SUITE
TIMING. AN INTERESTING NOTE HERE IS THE SHOWALTER VALUES FROM LATE
MORNING TO EARLY AFTERNOON DROP TO AROUND 0C WHICH SUGGESTS THE
WINDOW OF OPPORTUNITY FOR THUNDER. HOWEVER...WE WILL HOLD OFF ON
THE MENTION IN THE FORECAST/GRIDS UNTIL UPSTREAM TRENDS CAN BE
BETTER OBTAINED.
OVERALL...TEMPERATURES DURING THIS TIME FRAME WILL BE MAINLY
NON-DIURNAL DUE TO THE WARM ADVECTION THURSDAY NIGHT AND CONTINUING
TO RISE THROUGH FRIDAY.
THE LONG TERM WILL FEATURE A RETURN BACK TO WINTER TEMPERATURES AND
A VERY ACTIVE/FAST CYCLONIC FLOW ACROSS THE NORTHEAST CORRIDOR.
THE STORM THAT DEVELOPS OVER THE GREAT LAKES REGION SLOWLY FILLS AND
TRANSITIONS INTO A HUDSON/JAMES BAY LOW. WE WILL BE ON THE SOUTHERN
PERIPHERY OF THIS LOW WHICH KEEPS US RATHER UNSETTLED AND NEAR TO
BELOW NORMAL TEMPERATURES. THE TIMING OF SHORT WAVES WILL BE A
CHALLENGE IN THESE FAST FLOW REGIMES. PER THE GLOBAL MODELS...THE
FIRST WAVE ARRIVES SATURDAY WITH MAINLY THE EASTERN GREAT LAKES AND
SOME LAKE EFFECT SNOW IMPACTING PORTIONS OF THE ADIRONDACKS. THE
NEXT WAVE ARRIVES SUNDAY WITH A BIT MORE OF A SOUTHERN ROUTE. THIS
WAVE ATTEMPTS TO BE AN OVERACHIEVER PER THE ECMWF WITH THE GFS/GGEM
MUCH FLATTER AND MORE PROGRESSIVE. GIVEN THE RECENT TRACK RECORD OF
THE ECMWF...WE WILL PLACE SLIGHT CHANCE POPS FOR NOW.
LOOKING AHEAD INTO THE NEW WORK WEEK...THE HUDSON/JAMES BAY UPPER
LOW LOSES ITS GRIP AS WE MONITOR A POTENT PIECE OF ENERGY DIVE
SOUTHWARD FROM THE NORTHWEST TERRITORIES INTO THE INTERMOUNTAIN
WEST AND QUICKLY OUT ONTO THE CENTRAL PLAINS AND MID WEST BY
TUESDAY. THIS WILL REINTRODUCE THE CHANCE FOR ADDITIONAL WINTRY
PRECIPITATION LATE MONDAY INTO TUESDAY FOR THE ENTIRE CWFA.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
RATHER CHALLENGING IN THE NEAR TERM AS CLEAR SKIES WITH LIGHT WINDS
AND SNOW FROM EARLIER HAS RESULTED IN MVFR/IFR CONDITIONS AT KGFL
WITH OTHER TAF SITES HINTING AT THE POSSIBILITY. WE WILL PLACE A
TEMPO GROUP AT THIS TIME...AS WE MONITOR TRENDS AND UPSTREAM HIGH
AND MID LEVEL CLOUD COVER ADVECTING INTO THE REGION. THIS SHOULD
MINIMIZE THE FOG FROM SPREADING BUT IT WILL BE CLOSE.
AFTER SUNRISE...VISIBILITIES SHOULD IMPROVE AS WE WATCH THE NEXT
CLIPPER SYSTEM APPROACHING. THIS IS EXPECTED TO BRING ANOTHER
CHANCE FOR PRECIPITATION LATE THIS MORNING INTO THE AFTERNOON
HOURS. BOUNDARY LAYER TEMPERATURES WILL BE CLOSE TO RESULT IN
EITHER SN/RASN/RA. FOR NOW...WE FEEL KGFL WILL BE MAINLY SNOW WITH
A MIXTURE FURTHER SOUTH INTO KALB-KPSF AND TRANSITIONING TO ALL RAIN
KPOU. PRECIP SHOULD END THIS EVENING FROM WEST TO EAST RATHER
QUICKLY.
VARIABLE WINDS AT LESS THAN 6 KT WILL SWITCH TO A W-NW DIRECTION
BUT SWITCH TO A SOUTHERLY DIRECTION AND INCREASE TO AROUND 10 KTS
FOR WEDNESDAY MORNING...AND CONTINUE INTO THE AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...FG.
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND ARE GENERALLY FROM A FOOT TO THREE FEET. ALTHOUGH WE HAVE
WARMER TEMPERATURES IN THE FORECAST FOR THE LATTER PART OF THE
WEEK...EXCEPT FOR THURSDAY NIGHT...OVERNIGHT LOWS WILL BE AROUND OR
SLIGHTLY BELOW FREEZING WHICH SHOULD RESULT IN A SLOW MELT AND
HOPEFULLY MINIMIZE ANY FLOOD THREAT. RAINFALL TOTALS THURSDAY NIGHT
INTO FRIDAY MORNING ARE FORECAST TO GENERALLY BE IN THE QUARTER TO
HALF INCH RANGE...SO MUCH OF THIS RAINFALL SHOULD BE ABSORBED BY THE
CURRENT SNOWPACK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 25.7 INCHES THROUGH THE 16TH. THIS AMOUNT IS ONLY 0.3
INCHES FROM REACHING INTO THE TOP 10 FOR SNOWIEST FEBRUARYS SINCE
1885.
A LIGHT TO MODERATE SNOWFALL IS EXPECTED TUESDAY.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.5 INCHES 1899
8. 26.1 INCHES 1914
9. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 62.8 INCHES. NORMAL FOR
THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/WASULA
NEAR TERM...KL/WASULA
SHORT TERM...KL
LONG TERM...BGM
AVIATION...BGM/NAS
HYDROLOGY...KL/GJM
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
956 AM EST WED FEB 19 2014
.SYNOPSIS...
ANOTHER FAST MOVING LOW PRESSURE SYSTEM WILL BRING A
PERIOD OF SNOW AND RAIN TO THE REGION THIS AFTERNOON AND EVENING.
MILDER AIR WILL THEN MOVE INTO THE REGION BY THE END OF THE
WEEK...ALONG WITH A CHANCE OF RAIN SHOWERS AS A STRONG COLD FRONT
APPROACHES FROM THE GREAT LAKES THURSDAY NIGHT AND FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 945 AM...RADAR SHOWS PCPN ECHOES JUST ENTERING THE FAR WESTERN
AND SOUTHWESTERN PARTS OF THE FORECAST AREA...BUT WITH VERY DRY AIR
NEAR THE SURFACE...THE PCPN IS NOT LOKELY REACHING THE GROUND YET.
EXPECT THAT THE LOWER LEVELS WILL MOISTEN UP AND A PERIOD OF PCPN
WILL BE WIDESPREAD FOR A TIME ACROSS THE REGION THIS AFTERNOON.
MAINLY SNOW EXPECTED FOR MOST AREAS WITH RAIN MIXING IN OVER SOME
LOWER TERRAIN AREAS. HAVE ADJUSTED HOURLY TEMPS TO REFLECT CURRENT
CONDITIONS WHICH ARE HIGHLY VARIABLE BASED ON THE MESONET
OBSERVATIONS.
.PREVIOUS DISCUSSION...
AS OF 635 AM EST...HAVE RAISED SNOWFALL AMTS ACROSS THE LAKE
GEORGE/SARATOGA REGION...INTO THE BERKSHIRES AND SOUTHERN VT.
EXPECT 1-3 INCHES ACROSS THE LAKE GEORGE/SARATOGA REGION...AND 2-4
INCHES ACROSS SOUTHERN VT...AND ACROSS BERKSHIRE COUNTY. THIS WAS
BASED ON THE LATEST RAP13 AND HRRR...WHICH INDICATED A POSSIBLE
BURST OF CONVECTIVE PRECIPITATION BETWEEN 22Z-02Z ASSOCIATED WITH
THE PASSAGE OF THE UPPER TROUGH.
MEANWHILE...HIGH AND MID LEVEL CLOUDS ARE INCREASING ACROSS
THE REGION. TEMPS...WHICH INITIALLY DROPPED INTO THE SINGLE DIGITS
AND LOWER TEENS DUE TO SIGNIFICANT BOUNDARY LAYER DECOUPLING
ALONG WITH THE VERY DEEP SNOWCOVER...HAVE NOW STARTED TO RISE. WE
EXPECT MOST TEMPS TO RISE INTO THE TEENS TO LOWER 20S BY
SUNRISE...ALTHOUGH MAY STILL REMAIN IN THE LOWER TEENS ACROSS
PORTIONS OF THE UPPER HUDSON VALLEY.
OTHERWISE...WE HAVE A VERY CHALLENGING FORECAST AHEAD FOR
TODAY...AS A POTENT SHORTWAVE CURRENTLY CROSSING THE MIDWEST
TRANSLATES RAPIDLY EASTWARD. THIS FEATURE...IN COMBINATION WITH A
WEAKER LEAD UPPER LEVEL IMPULSE...HAS TRIGGERED CONSIDERABLE
ELEVATED CONVECTION ACROSS THE NORTHERN APPALACHIANS AND UPPER
OHIO VALLEY EARLY THIS MORNING. THE LATEST RAP13 AND HRRR INDICATE
THAT THE REMNANTS OF THIS CONVECTION SHOULD TRACK EAST
NORTHEAST...ACROSS MAINLY CENTRAL AND SOUTHERN PORTIONS OF THE
REGION THIS AFTERNOON. THUS...PRECIP WILL BE MOST FAVORED FOR THE
EASTERN CATSKILLS...NORTHEAST INTO THE CAPITAL
REGION...BERKSHIRES...MID HUDSON VALLEY AND NW CT...AND SOUTHERN
VT...WITH POTENTIALLY LESS TO THE N AND W. HOWEVER...SHOULD THIS
CONVECTION WEAKEN...IT IS POSSIBLE THAT BETTER MOISTURE TRANSPORT
COULD ALLOW FOR PRECIP TO DEVELOP FURTHER NORTHWARD.
FURTHER COMPLICATING THE FORECAST WILL BE THE EXPECTED THERMAL
PROFILES AS THE PRECIP OCCURS. FORECAST SOUNDINGS...ESP SOUTH OF
ALBANY...INDICATE AN ABOVE FREEZING LAYER DEVELOPING AROUND 925
MB. THIS...IN COMBINATION WITH SOME BOUNDARY LAYER WARMING...WOULD
PROMOTE RAIN. HOWEVER...WITH A BURST OF STRONG VERTICAL VELOCITY
AND WET BULB COOLING...THE LOW LEVELS SHOULD COOL SUFFICIENTLY TO
ALLOW FOR SNOW AFTER A PERIOD OF RAIN/SNOW MIX IN SOME VALLEY
AREAS. SO...ASSUMING WE GET INTO THE BETTER DYNAMICAL FORCING THIS
AFTERNOON...WE HAVE SIDED MORE WITH SNOW THAN RAIN FOR MOST AREAS.
THIS SHOULD GIVE MOST VALLEY AREAS FROM ALBANY SOUTHWARD AROUND
AN INCH OF SNOW...WITH 1-3 INCHES POSSIBLE ACROSS PORTIONS OF THE
LAKE GEORGE/SARATOGA REGION...AS WELL AS HIGHER ELEVATIONS
SURROUNDING THE HUDSON VALLEY...AND 2-4 INCHES ACROSS THE
BERKSHIRES AND SOUTHERN VT. AGAIN...THIS IS A VERY TRICKY
SITUATION...AND SHOULD ANY HEAVIER PRECIP LINGER OVER ANY ONE AREA
LONGER THAN EXPECTED...HIGHER SNOWFALL AMTS COULD OCCUR.
HAVE SIDED WITH...OR EVEN COOLER THAN THE COLDER MOS FOR TODAY/S
MAX TEMPS...WITH MID/UPPER 30S IN VALLEY AREAS FROM ALBANY
SOUTH...AND GENERALLY LOWER/MID 30S TO THE NORTH...WITH GENERALLY
20S TO LOWER 30S ACROSS HIGHER ELEVATIONS.
SOUTH TO SOUTHEAST WINDS WILL INCREASE THIS MORNING THROUGH EARLY
AFTERNOON...SIMILAR TO YESTERDAY...WITH SOME GUSTS POSSIBLY
REACHING UP TO 30-35 MPH ACROSS PORTIONS OF SW VT...THE
BERKSHIRES...AND TACONICS...AND POSSIBLY UP TO 25-30 MPH WITHIN
THE CAPITAL REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...AS THE MAIN SHORTWAVE TROUGH PASSES THROUGH...ANOTHER
BURST OF PRECIPITATION IS EXPECTED. THE PRECIP SHOULD BE MORE
SHOWERY IN NATURE. IN FACT...MODEL SOUNDINGS ACTUALLY INDICATE RATHER
STEEP LAPSE RATES IN THE 700-500 HPA LAYER...WITH THE LATEST RAP13
INDICATING AS STEEP AS 8-8.5 C/KM. THESE STEEP LAPSE RATES...COMBINED
WITH ASCENT FROM THE APPROACHING/PASSING SHORTWAVE TROUGH...COULD
EVEN ALLOW FOR SOME ISOLATED THUNDERSTORMS ACROSS THE
REGION...SOME OF WHICH COULD PRODUCE GRAUPEL/SMALL HAIL. IN THE
WAKE OF THE TROUGH PASSAGE...STRONG WEST/NORTHWEST WINDS WILL
LIKELY DEVELOP...WITH ENHANCED FLOW DOWN THE MOHAWK RIVER
VALLEY/CAPITAL REGION AND BERKSHIRES EXPECTED. THIS COULD ALLOW
FOR SOME GUSTS TO REACH 35-40 MPH AT TIMES LATER THIS EVENING
UNTIL SHORTLY AFTER MIDNIGHT. SKIES SHOULD INITIALLY REMAIN MOSTLY
CLOUDY...BUT AS STRONG SUBSIDENCE AND SOME DOWNSLOPING
OCCURS...SKIES SHOULD TREND TO MOSTLY CLEAR WELL AFTER MIDNIGHT.
TEMPS WILL BE TRICKY...AS THERE COULD BE A WINDOW OF RAPID
DECOUPLING RIGHT AROUND OR EVEN AFTER DAYBREAK. HOWEVER...WIND AND
SOME CLOUDS SHOULD KEEP THIS FROM OCCURRING FOR MOST OF THE NIGHT.
SO...ALTHOUGH HAVE SIDED WITH THE COOLER MOS...DID NOT GO MUCH
COOLER. STILL EXPECT WIDESPREAD TEENS AND 20S ACROSS THE REGION.
THURSDAY...HIGH PRESSURE RIDGE WILL TRANSLATE EAST ACROSS THE
REGION. SKIES SHOULD BE MOSTLY SUNNY IN THE MORNING...WITH CLOUDS
INCREASING IN THE AFTERNOON. SOME LIGHT PRECIPITATION COULD REACH
FAR WESTERN AREAS TOWARD OR JUST AFTER SUNSET...MAINLY AS
RAIN...ALTHOUGH A RAIN/SLEET/SNOW MIX COULD OCCUR IN HIGHER
ELEVATIONS. EXPECT MAX TEMPS TO REACH THE UPPER 30S TO LOWER 40S
IN MOST VALLEY AREAS...AND LOWER/MID 30S FOR HIGHER ELEVATIONS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
AS POTENT STORM WRAPS UP ACROSS THE CENTRAL GREAT LAKES
REGION...EQUALLY IMPRESSIVE LOW LEVEL JET AND ISENTROPIC LIFT WILL
UNFOLD ACROSS UPSTATE NEW YORK THURSDAY NIGHT. THIS WILL ALLOW FOR
BANDS OF PRECIPITATION TO EVOLVE FROM SOUTH TO NORTH WITH THE PEAK
OF THE LOW LEVEL FORCING TAKING PLACE ACROSS THE ADIRONDACKS.
THERMAL PROFILES ACROSS THE REGION WILL BE TRANSITIONING WITHIN THE
WARM ADVECTION AS BOUNDARY LAYER TEMPS MAY STRUGGLE FOR A PERIOD OF
TIME. THIS SETS THE STAGE FOR SNOW MIXING WITH SLEET/FREEZING RAIN
IMPACTING MAINLY THE ADIRONDACKS AND SOUTHERN
GREENS...ALTHOUGH...COULD NOT RULE OUT SOME ISOLATED SHELTERED
LOCATIONS RECEIVING A WINTRY MIX IN THE MOHAWK AND CENTRAL-NORTHERN
HUDSON RIVER VALLEY. HOWEVER...THE STRENGTH OF THE WARM ADVECTION
WILL EVENTUALLY OVERCOME THE SHALLOW SUB FREEZING TEMPERATURES
FRIDAY MORNING FOR ALL OF THE PRECIPITATION TO BECOME RAIN.
ALONG WITH THE TEMPERATURES INCREASING...SO DOES THE DEWPOINT TO
ABOVE FREEZING. AS THIS WARMER AND MORE MOIST AIR ADVECTS OVER A
SNOW COVERED GROUND WOULD RESULT IN FOG AS WE WILL PLACE THIS IN THE
GRIDS. STRONG COLD FRONT WITH A FAIRLY TIGHT THERMAL GRADIENT FROM
+8C AT H850 OVER EASTERN NY TO -6C OVER WESTERN NY WILL QUICKLY MOVE
ACROSS THE REGION BY EARLY AFTERNOON PER THE LATEST NCEP MODEL SUITE
TIMING. AN INTERESTING NOTE HERE IS THE SHOWALTER VALUES FROM LATE
MORNING TO EARLY AFTERNOON DROP TO AROUND 0C WHICH SUGGESTS THE
WINDOW OF OPPORTUNITY FOR THUNDER. HOWEVER...WE WILL HOLD OFF ON
THE MENTION IN THE FORECAST/GRIDS UNTIL UPSTREAM TRENDS CAN BE
BETTER OBTAINED.
OVERALL...TEMPERATURES DURING THIS TIME FRAME WILL BE MAINLY
NON-DIURNAL DUE TO THE WARM ADVECTION THURSDAY NIGHT AND CONTINUING
TO RISE THROUGH FRIDAY.
THE LONG TERM WILL FEATURE A RETURN BACK TO WINTER TEMPERATURES AND
A VERY ACTIVE/FAST CYCLONIC FLOW ACROSS THE NORTHEAST CORRIDOR.
THE STORM THAT DEVELOPS OVER THE GREAT LAKES REGION SLOWLY FILLS AND
TRANSITIONS INTO A HUDSON/JAMES BAY LOW. WE WILL BE ON THE SOUTHERN
PERIPHERY OF THIS LOW WHICH KEEPS US RATHER UNSETTLED AND NEAR TO
BELOW NORMAL TEMPERATURES. THE TIMING OF SHORT WAVES WILL BE A
CHALLENGE IN THESE FAST FLOW REGIMES. PER THE GLOBAL MODELS...THE
FIRST WAVE ARRIVES SATURDAY WITH MAINLY THE EASTERN GREAT LAKES AND
SOME LAKE EFFECT SNOW IMPACTING PORTIONS OF THE ADIRONDACKS. THE
NEXT WAVE ARRIVES SUNDAY WITH A BIT MORE OF A SOUTHERN ROUTE. THIS
WAVE ATTEMPTS TO BE AN OVERACHIEVER PER THE ECMWF WITH THE GFS/GGEM
MUCH FLATTER AND MORE PROGRESSIVE. GIVEN THE RECENT TRACK RECORD OF
THE ECMWF...WE WILL PLACE SLIGHT CHANCE POPS FOR NOW.
LOOKING AHEAD INTO THE NEW WORK WEEK...THE HUDSON/JAMES BAY UPPER
LOW LOSES ITS GRIP AS WE MONITOR A POTENT PIECE OF ENERGY DIVE
SOUTHWARD FROM THE NORTHWEST TERRITORIES INTO THE INTERMOUNTAIN
WEST AND QUICKLY OUT ONTO THE CENTRAL PLAINS AND MID WEST BY
TUESDAY. THIS WILL REINTRODUCE THE CHANCE FOR ADDITIONAL WINTRY
PRECIPITATION LATE MONDAY INTO TUESDAY FOR THE ENTIRE CWFA.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
RATHER CHALLENGING IN THE NEAR TERM AS CLEAR SKIES WITH LIGHT WINDS
AND SNOW FROM EARLIER HAS RESULTED IN MVFR/IFR CONDITIONS AT KGFL
WITH OTHER TAF SITES HINTING AT THE POSSIBILITY. WE WILL PLACE A
TEMPO GROUP AT THIS TIME...AS WE MONITOR TRENDS AND UPSTREAM HIGH
AND MID LEVEL CLOUD COVER ADVECTING INTO THE REGION. THIS SHOULD
MINIMIZE THE FOG FROM SPREADING BUT IT WILL BE CLOSE.
AFTER SUNRISE...VISIBILITIES SHOULD IMPROVE AS WE WATCH THE NEXT
CLIPPER SYSTEM APPROACHING. THIS IS EXPECTED TO BRING ANOTHER
CHANCE FOR PRECIPITATION LATE THIS MORNING INTO THE AFTERNOON
HOURS. BOUNDARY LAYER TEMPERATURES WILL BE CLOSE TO RESULT IN
EITHER SN/RASN/RA. FOR NOW...WE FEEL KGFL WILL BE MAINLY SNOW WITH
A MIXTURE FURTHER SOUTH INTO KALB-KPSF AND TRANSITIONING TO ALL RAIN
KPOU. PRECIP SHOULD END THIS EVENING FROM WEST TO EAST RATHER
QUICKLY.
VARIABLE WINDS AT LESS THAN 6 KT WILL SWITCH TO A W-NW DIRECTION
BUT SWITCH TO A SOUTHERLY DIRECTION AND INCREASE TO AROUND 10 KTS
FOR WEDNESDAY MORNING...AND CONTINUE INTO THE AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...FG.
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND ARE GENERALLY FROM A FOOT TO THREE FEET. ALTHOUGH WE HAVE
WARMER TEMPERATURES IN THE FORECAST FOR THE LATTER PART OF THE
WEEK...EXCEPT FOR THURSDAY NIGHT...OVERNIGHT LOWS WILL BE AROUND OR
SLIGHTLY BELOW FREEZING WHICH SHOULD RESULT IN A SLOW MELT AND
HOPEFULLY MINIMIZE ANY FLOOD THREAT. RAINFALL TOTALS THURSDAY NIGHT
INTO FRIDAY MORNING ARE FORECAST TO GENERALLY BE IN THE QUARTER TO
HALF INCH RANGE...SO MUCH OF THIS RAINFALL SHOULD BE ABSORBED BY THE
CURRENT SNOWPACK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 25.7 INCHES THROUGH THE 16TH. THIS AMOUNT IS ONLY 0.3
INCHES FROM REACHING INTO THE TOP 10 FOR SNOWIEST FEBRUARYS SINCE
1885.
A LIGHT TO MODERATE SNOWFALL IS EXPECTED TUESDAY.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.5 INCHES 1899
8. 26.1 INCHES 1914
9. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 62.8 INCHES. NORMAL FOR
THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/GJM
NEAR TERM...GJM/KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...BGM/NAS
HYDROLOGY...KL/GJM
CLIMATE...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
952 AM EST WED FEB 19 2014
.SYNOPSIS...
A COLD FRONT PUSHES ACROSS THE REGION THIS AFTERNOON. HIGH
PRESSURE BUILDS IN TONIGHT THROUGH THURSDAY. A FRONTAL SYSTEM
MOVES THROUGH THE REGION LATE THURSDAY NIGHT AND FRIDAY. WEAK HIGH
PRESSURE BUILDS IN SATURDAY. A COLD FRONT MOVES THROUGH SUNDAY.
COLD CANADIAN HIGH PRESSURE BUILDS FOR MONDAY. A WEAK LOW MOVES
ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST ON TRACK. PCPN MOVING TO WESTERN NJ ATTM. EXPECT RAIN IN
THE NY METRO FOR THE LUNCH HOUR. FREEZING RAIN FOR THE WESTERN
AREAS AS TEMPS ARE STILL IN THE 20S...BUT RISING QUICKLY.
IMPORTANT TO CONVEY IS THAT EVEN AS TEMPS WARM ABOVE
FREEZING...SURFAVE/PAVEMENT TEMPS WILL LAG BEHIND (LOWS WERE IN
THE SINGLE DIGITS AND TEENS JUST A FEW HOURS AGO). THUS...ICING
CONCERNS HERE ARE SIGNIFICANT...ESPECIALLY ON UNTREATED WALKWAYS.
OTHER CONCERN IS THE CONVECTION...LIGHTNING IS BEING OBSERVED
SOUTH AND WEST OF KPHL ATTM. EXAMINATION OF RAP SOUNDING SUGGEST
ONLY LIMITED ELEVATED INSTABILITY...SO WILL NOT INCLUDE IN FCST UP
HERE.
LASTLY...LATEST RAP RUN SUGGESTS THAT RA/SN SHOWER POTENTIAL IN WAKE
OF THE FRONT EARLY THIS EVENING. WILL EVACUATE THAT FOR THE NOON
UPDATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
FOR TONIGHT...HIGH PRESSURE BUILDING IN FROM THE WEST AND OVERALL
JET STREAM LIFTING NORTH OF THE REGION...A MODERATION OF THE
AIRMASS WILL CONTINUE. STRONG RIDGING ALOFT WITH HIGH PRESSURE
BUILDING IN WILL PROVIDE STRONG SUBSIDENCE. THIS WILL ALLOW FOR
CLOUDS TO DECREASE RAPIDLY LATE.
LOWS WERE A BLEND OF MET/MAV/GMOS AND LOWERED A DEGREE IN SOME SPOTS
TO ACCOUNT FOR SOME RADIATIONAL COOLING. THIS WILL BE MORE
PRONOUNCED WHERE THERE IS MORE RESIDUAL SNOW PACK AND LIGHTER
WINDS...ACROSS THE INTERIOR.
FOR THURSDAY...THE HIGH PRESSURE AREA QUICKLY MOVES AND BUILDS
OFFSHORE WITH A CONTINUED WARM AIR ADVECTION FROM SOUTHERLY FLOW.
IN ADDITION...MID AND HIGH LEVEL CLOUDS WILL STREAM IN AHEAD OF
THE NEXT FRONTAL SYSTEM IN THE AFTERNOON WITH POSSIBLE SHOWERS
DEVELOPING LATE WITH THE APPROACH OF THE WARM FRONT. THE JET
STREAM CONTINUES TO PUSH NORTH AS THE AIRMASS CONTINUES TO
MODERATE.
HIGHS THURSDAY WERE A BLEND OF ECE/GMOS SUBTRACTED BY A DEGREE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A WARM FRONT APPROACHES THE AREA THURSDAY NIGHT AS SURFACE LOW
PRESSURE MOVES THROUGH THE GREAT LAKES. WITH THE LOW WELL TO THE
WEST AND THE COLD FRONT QUICKLY APPROACHING FROM THE WEST THE WARM
FRONT MAY NOT MOVE THROUGH THURSDAY NIGHT INTO FRIDAY MORNING.
LEANED TOWARD THE SLIGHTLY SLOWER COLD FRONT TIMING OF THE GFS AND
ECMWF...MOVING THROUGH FRIDAY AFTERNOON.
INCREASING ISENTROPIC LIFT WILL RESULT IN WARM ADVECTION LIGHT RAIN.
MID LEVELS STILL FORECAST TO DRY SO HAVE MAINTAINED THE DRIZZLE
THURSDAY NIGHT INTO FRIDAY MORNING...AND WITH THE SURFACE WARM FRONT
IN THE VICINITY KEPT AREAS OF FOG.
INSTABILITY INCREASES AHEAD OF THE COLD FRONT FRIDAY...MAINLY
ELEVATED...AND AN 60KT TO 70KT 850MB JET WILL MOVE THROUGH AHEAD OF
THE COLD FRONT...AIDING IN THE INSTABILITY AND CHANCES OF
CONVECTION.
WEAK RIDGE BUILDS IN BEHIND THE FRONT FOR FRIDAY NIGHT INTO
SATURDAY. THE UPPER AND SURFACE LOWS REMAIN ACROSS EASTERN CANADA
AND ANOTHER SHORTWAVE ROTATING THROUGH WILL BRING ANOTHER COLD FRONT
THROUGH THE REGION SUNDAY. WITH LITTLE MOISTURE HAVE KEPT MUCH OF
THE AREA DRY...WITH A CHANCE OF SNOW SHOWERS ACROSS THE INLAND
HIGHER TERRAIN. FLURRIES POSSIBLE FARTHER SOUTH AND EAST BUT NOT
CONFIDENT OF THIS AT THIS TIME. THE COLD FRONTAL PASSAGE SUNDAY AND
CANADIAN HIGH PRESSURE BUILDING IN WILL BRING AN END TO THE WARM
WEATHER..RETURNING TEMPERATURES TO BELOW NORMAL.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
A FRONTAL SYSTEM LIFTS THROUGH THE TERMINALS THIS AFTERNOON. NO
SIGNIFICANT CHANGES MADE TO THE PREVIOUS TAF PACKAGE...BUT LOWER
CIGS MAY ARRIVE AN HOUR OR SO EARLIER THAN FORECAST. THERE ARE
SOME LIGHTNING STRIKES ACROSS SE PA AND THE MID-ATLANTIC REGION.
LOW CONFIDENCE IF LIGHTNING WILL IMPACT KNYC TERMINALS...BUT IT IS
POSSIBLE A STRIKE OR 2 COULD WORK THEIR WAY UP THE COAST.
PTYPE RAIN...EXCEPT FOR KSWF...WHERE A BRIEF PERIOD OF -FZRASN IS
POSSIBLE AT ONSET. TEMPS SHOULD WARM UP QUICKLY ENOUGH FOR ONLY
ABOUT AN HOUR OR TWO OF FROZEN/FREEZING PRECIP.
PATCHY BR ACROSS KHPN...KISP...KGON...AND KBDR EARLY THIS
MORNING...WITH MVFR CONDITIONS POSSIBLE. MORE NOTICEABLE DROP IN
VSBYS LATER TODAY WITH GROUND FOG. CITY TERMINALS HAVE A BETTER
CHANCE OF IFR/LIFR...WITH A LOW TO MEDIUM CHANCE OF SEEING VLIFR.
TIMING FOR FOG...17Z AND 21Z. VSBY IMPROVES AFTER 21Z...WITH CIGS
IMPROVING IN THE EVENING.
LIGHT AND VARIABLE WINDS. SE WINDS INCREASE WED MORNING...WITH
OCCASIONAL GUSTS TO 25 KT ACROSS COASTAL TERMINALS. A PERIOD OF
LIGHT AND VARIABLE WINDS POSSIBLE IN THE AFTERNOON AS SURFACE LOW
WORKS ACROSS...BEFORE WINDS BECOME W AND INCREASE IN THE LATE
AFTERNOON. THEN GUSTY W WINDS TO 20-25KT AFTER 00Z.
MARGINAL LLWS ACROSS CITY/COASTAL TERMINALS BETWEEN 14Z AND 20Z
WITH 40-45KT 2 KFT SOUTHERLY JET.
...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: AMENDMENTS MAY BE NEEDED INTO THIS AFTERNOON
FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL SOME
UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN TO
LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED INTO THIS AFTERNOON
FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL SOME
UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN TO
LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED THIS AFTERNOON FOR
IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL SOME
UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN TO
LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS YELLOW...WHICH
IMPLIES SLANT RANGE VISIBILITY 4-6SM OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED THIS AFTERNOON FOR
IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL SOME
UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN TO
LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED THIS AFTERNOON FOR
IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL SOME
UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN TO
LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED THIS AFTERNOON FOR
IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL SOME
UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN TO
LESS THAN 1 MILE. TIMING OF ONSET 16-18Z.
.OUTLOOK FOR 15Z THU THROUGH SUN...
.THU-THU EVENING...VFR.
.LATE THU NIGHT-FRI...MVFR OR LOWER CONDITIONS AND LLWS LIKELY IN
RAIN. A TSTM POSSIBLE. LATE DAY OR EVENING COLD FROPA.
.FRI NIGHT-SAT...VFR. W WINDS G20-25KT.
.SUN...VFR.
&&
.MARINE...
SCA CONTINUES ON THE OCEAN THROUGH THURSDAY MORNING EAST OF FIRE
ISLAND INLET. OTHERWISE...SCA ON OCEAN WEST OF FIRE ISLAND INLET
THROUGH TONIGHT. MAINLY SUB SCA CONDITIONS ON OTHER WATERS BUT
OCCASIONAL 25 KT GUSTS CANNOT BE RULED OUT TODAY.
SMALL CRAFT SEAS ON THE OCEAN WATERS WILL BE LIKELY THURSDAY NIGHT
INTO FRIDAY AS A SOUTHERLY FLOW INCREASES AHEAD OF A COLD FRONT.
SOUTHERLY WIND SPEEDS AND GUSTS MAY INCREASE TO NEAR SMALL CRAFT
LEVELS LATE THURSDAY NIGHT INTO FRIDAY MORNING. WITH A COLD FRONTAL
PASSAGE FRIDAY AFTERNOON THE WIND SHIFTS TO THE WEST AND DIMINISHES.
SEAS ON THE OCEAN REMAIN AT SMALL CRAFT LEVELS INTO SATURDAY
EVENING.
WIND GUSTS ON THE OCEAN MAY ONCE AGAIN INCREASE TO NEAR SMALL CRAFT
LEVELS SUNDAY NIGHT BEHIND A COLD FRONT MOVING THROUGH THE WATERS
SUNDAY.
&&
.HYDROLOGY...
RAINFALL AMOUNTS OF AROUND A QUARTER TO A THIRD OF AN INCH IS
EXPECTED DURING THE DAY TODAY WITH THE COLD FRONT.
A QUARTER TO HALF INCH OF RAINFALL IS LIKELY THURSDAY NIGHT INTO
FRIDAY.
&&
.EQUIPMENT...
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR NYZ067-069.
NJ...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR NJZ002-004-103-
105-107.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ355.
SMALL CRAFT ADVISORY UNTIL NOON EST THURSDAY FOR ANZ350-353.
&&
$$
SYNOPSIS...JM/MET
NEAR TERM...TONGUE
SHORT TERM...JM
LONG TERM...MET
AVIATION...MPS
MARINE...JM/MET
HYDROLOGY...JM/MET
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
714 AM EST WED FEB 19 2014
.SYNOPSIS...
A COLD FRONT PUSHES ACROSS THE REGION THIS AFTERNOON. HIGH PRESSURE
FROM THE SOUTH AND WEST BUILDS IN TONIGHT AND BUILDS OFFSHORE ON
THURSDAY. A FRONTAL SYSTEM MOVES THROUGH THE REGION THURSDAY NIGHT
AND FRIDAY. WEAK HIGH PRESSURE BUILDS IN SATURDAY. A COLD FRONT
MOVES THROUGH SUNDAY. CANADIAN HIGH PRESSURE BUILDS FOR MONDAY. A
WEAK LOW MOVES ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THERE ARE STILL SOME AREAS OF BLACK ICE FROM REFREEZING OF MELTED
SNOW THE PREVIOUS DAY. SPS REGARDING THIS REMAINS IN EFFECT
THROUGH EARLY MORNING.
FORECAST MAINLY ON TRACK. PRECIP DEVELOPING IN WESTERN PA...WITH
CURRENT LINEAR TRACKING WILL BE MOVING INTO WESTERN PORTIONS OF
THE REGION AROUND 16-17Z. FREEZING RAIN STILL LOOKS TO BE MAIN PRECIP
TYPE ACROSS PARTS OF INTERIOR AS 925 AND 850MB TEMPS HAVE RISEN A
FEW DEGREES ABOVE FREEZING ACCORDING TO RUC13 ANALYSIS. AFTER
17Z...COASTAL LOCATIONS SHOULD ALREADY BE WELL ABOVE FREEZING WITH
INTERIOR SECTIONS ALSO RISING ABOVE FREEZING BY THAT TIME.
FOR TODAY...MAIN FOCUS IS THE PRECIPITATION ASSOCIATED WITH THE
COLD FRONT AND ITS TIMING. THIS IS NOT A SIGNIFICANT SYSTEM WITH
RATHER WEAK MAGNITUDES OF THE PARENT LOW PRESSURE AND THAT OF THE
COLD FRONT.
THERE IS ENOUGH CONFIDENCE FOR THE LIKELIHOOD OF MEASURABLE
PRECIPITATION BUT THE MAGNITUDE OF THE 850-700MB FRONTOGENESIS IS
NOT LARGE. HOWEVER...THERE IS ENOUGH OF A COHERENT SIGNAL OF THIS
FRONTOGENESIS AND AGREE TOO WITH LOW TO MID LEVEL WARM AIR
ADVECTION CONTRIBUTING TO THIS FRONTOGENESIS AMONGST THE NUMERICAL
WEATHER PREDICTION TO MODELS. THIS SUGGEST MAINTENANCE AND PERHAPS
EVEN SOME ENHANCEMENT TO PRECIP AS IT MOVES ACROSS THE AREA.
IN ADDITION...EVEN THOUGH AT FIRST GLANCE THE POPS ARE TRENDING
HIGHER THAN WHEN MOST MODELS SHOW PRECIP ARRIVING...WILL KEEP THIS
EARLIER TIMING SINCE PRECIP TYPICALLY DEVELOPS AND ARRIVES SOONER
THAN WHAT MODELS SHOW WITH THE WARM AIR ADVECTION ALOFT.
THEREFORE...EARLIER TIMING MEANS SURFACE TEMPERATURES FOR THE
INTERIOR WILL STILL BE AT FREEZING OR BELOW WHEN THE PRECIP
ARRIVES. THERE IS WARM ADVECTION ALOFT EVIDENT AT THE 850MB LEVEL.
THIS WILL LIKELY RACE AHEAD OF THE SURFACE WARMER AIR AND WITH THE
INTERIOR AREAS NEAR HIGHER TERRAIN AND WITH BLOCKAGE FROM
SOUTHERLY FLOW...THERE WILL BE LIKELY BE AREAS WHICH WILL BE COLD
ENOUGH FOR FREEZING RAIN.
ADDING TO THE UNCERTAINTY IS THE POTENTIAL FOR STRONGER VERTICAL
VELOCITY TO COOL THE COLUMN AND IN THIS CASE...SNOW SHOWERS WOULD BE
THE LIKELY RESULT. A COATING OF SNOW WILL BE POSSIBLE IN THIS
SCENARIO. BUT THINKING AT THE MOMENT FREEZING RAIN WILL BE THE MORE
LIKELY OF PRECIP TYPES FOR INTERIOR AREAS THIS MORNING. SO JUST
LEFT SNOW SHOWERS AS A CHANCE FOR THE MORNING.
THEREFORE KEEPING FREEZING RAIN ADVISORY AND HEADLINES AS THEY
WERE BEFORE. BY THE TIME THE LINE OF PRECIP ARRIVES TOWARDS
SOUTHERN CONNECTICUT...TEMPERATURES WILL LIKELY ALREADY BE ABOVE
FREEZING FOR MOST PLACES.
PATCHY FOG WILL BE SEEN AS WELL FOR THE AFTERNOON WITH MOIST INFLOW
FROM ONSHORE FLOW AHEAD OF THE COLD FRONT AND LINGERING MOISTURE
AFTER SHOWERS MOVE THROUGH.
HIGHS WERE A BLEND OF NAM12 AND COOLER MAV GUIDANCE YIELDING UPPER
30S TO LOWER 40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
FOR TONIGHT...AT THE START OF THE EVENING...THERE WILL BE A
CHANCE FOR SOME LINGERING RAIN SHOWERS BEHIND THE COLD FRONT.
WINDS WILL BE TURNING MORE WESTERLY AND EVENTUALLY NORTHWESTERLY.
WITH HIGH PRESSURE BUILDING IN FROM THE WEST AND OVERALL JET STREAM
LIFTING NORTH OF THE REGION...A MODERATION OF THE AIRMASS WILL
CONTINUE. STRONG RIDGING ALOFT WITH HIGH PRESSURE BUILDING IN WILL
PROVIDE STRONG SUBSIDENCE. THIS WILL ALLOW FOR CLOUDS TO DECREASE
RAPIDLY LATE.
LOWS WERE A BLEND OF MET/MAV/GMOS AND LOWERED A DEGREE IN SOME SPOTS
TO ACCOUNT FOR SOME RADIATIONAL COOLING. THIS WILL BE MORE
PRONOUNCED WHERE THERE IS MORE RESIDUAL SNOW PACK AND LIGHTER
WINDS...ACROSS THE INTERIOR.
FOR THURSDAY...THE HIGH PRESSURE AREA QUICKLY MOVES AND BUILDS
OFFSHORE WITH A CONTINUED WARM AIR ADVECTION FROM SOUTHERLY FLOW.
IN ADDITION...MID AND HIGH LEVEL CLOUDS WILL STREAM IN AHEAD OF
THE NEXT FRONTAL SYSTEM IN THE AFTERNOON WITH POSSIBLE SHOWERS
DEVELOPING LATE WITH THE APPROACH OF THE WARM FRONT. THE JET
STREAM CONTINUES TO PUSH NORTH AS THE AIRMASS CONTINUES TO
MODERATE.
HIGHS THURSDAY WERE A BLEND OF ECE/GMOS SUBTRACTED BY A DEGREE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A WARM FRONT APPROACHES THE AREA THURSDAY NIGHT AS SURFACE LOW
PRESSURE MOVES THROUGH THE GREAT LAKES. WITH THE LOW WELL TO THE
WEST AND THE COLD FRONT QUICKLY APPROACHING FROM THE WEST THE WARM
FRONT MAY NOT MOVE THROUGH THURSDAY NIGHT INTO FRIDAY MORNING.
LEANED TOWARD THE SLIGHTLY SLOWER COLD FRONT TIMING OF THE GFS AND
ECMWF...MOVING THROUGH FRIDAY AFTERNOON.
INCREASING ISENTROPIC LIFT WILL RESULT IN WARM ADVECTION LIGHT RAIN.
MID LEVELS STILL FORECAST TO DRY SO HAVE MAINTAINED THE DRIZZLE
THURSDAY NIGHT INTO FRIDAY MORNING...AND WITH THE SURFACE WARM FRONT
IN THE VICINITY KEPT AREAS OF FOG.
INSTABILITY INCREASES AHEAD OF THE COLD FRONT FRIDAY...MAINLY
ELEVATED...AND AN 60KT TO 70KT 850MB JET WILL MOVE THROUGH AHEAD OF
THE COLD FRONT...AIDING IN THE INSTABILITY AND CHANCES OF
CONVECTION.
WEAK RIDGE BUILDS IN BEHIND THE FRONT FOR FRIDAY NIGHT INTO
SATURDAY. THE UPPER AND SURFACE LOWS REMAIN ACROSS EASTERN CANADA
AND ANOTHER SHORTWAVE ROTATING THROUGH WILL BRING ANOTHER COLD FRONT
THROUGH THE REGION SUNDAY. WITH LITTLE MOISTURE HAVE KEPT MUCH OF
THE AREA DRY...WITH A CHANCE OF SNOW SHOWERS ACROSS THE INLAND
HIGHER TERRAIN. FLURRIES POSSIBLE FARTHER SOUTH AND EAST BUT NOT
CONFIDENT OF THIS AT THIS TIME. THE COLD FRONTAL PASSAGE SUNDAY AND
CANADIAN HIGH PRESSURE BUILDING IN WILL BRING AN END TO THE WARM
WEATHER..RETURNING TEMPERATURES TO BELOW NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
FRONTAL SYSTEM APPROACHES THE TERMINALS THIS
MORNING AND CROSSES THE FORECAST AREA DURING THIS AFTERNOON. THIS
WILL ALLOW RAIN TO MOVE IN AFTER 16Z.
AT KSWF...SOME -FZRASN IS POSSIBLE AT ONSET. SURFACE TEMPS MAY TAKE
UNTIL...BUT TEMPS SHOULD WARM UP QUICKLY ENOUGH FOR ONLY ABOUT AN
HOUR OR TWO OF FROZEN/FREEZING PRECIP.
PATCHY BR ACROSS KHPN...KISP...KGON...AND KBDR EARLY THIS
MORNING...WITH MVFR CONDITIONS POSSIBLE. MORE NOTICEABLE DROP IN
VSBYS LATER TODAY WITH GROUND FOG. CITY TERMINALS HAVE A BETTER
CHANCE OF IFR/LIFR...WITH A LOW TO MEDIUM CHANCE OF SEEING VLIFR.
TIMING FOR FOG...17Z AND 21Z. VSBY IMPROVES AFTER 21Z...WITH CIGS
IMPROVING IN THE EVENING.
LIGHT AND VARIABLE WINDS. SE WINDS INCREASE WED MORNING...WITH
OCCASIONAL GUSTS TO 25 KT ACROSS COASTAL TERMINALS. A PERIOD OF
LIGHT AND VARIABLE WINDS POSSIBLE IN THE AFTERNOON AS SURFACE LOW
WORKS ACROSS...BEFORE WINDS BECOME W AND INCREASE IN THE LATE
AFTERNOON. THEN GUSTY W WINDS TO 20-25KT AFTER 00Z.
MARGINAL LLWS ACROSS CITY/COASTAL TERMINALS BETWEEN 14Z AND 20Z
WITH 40-45KT 2 KFT SOUTHERLY JET.
...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: AMENDMENTS MAY BE NEEDED THIS MORNING AND
AFTERNOON FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL
SOME UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN
TO LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED THIS MORNING AND
AFTERNOON FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL
SOME UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN
TO LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED WEDNESDAY MORNING AND
AFTERNOON FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL
SOME UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN
TO LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS YELLOW...WHICH
IMPLIES SLANT RANGE VISIBILITY 4-6SM OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED WEDNESDAY MORNING AND
AFTERNOON FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL
SOME UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN
TO LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED WEDNESDAY MORNING AND
AFTERNOON FOR IFR/LIFR VSBY. LOW TO MEDIUM CHANCE OF VLIFR. STILL
SOME UNCERTAINTY...BUT CONFIDENCE IS INCREASING THAT VSBYS COME DOWN
TO LESS THAN 1 MILE. TIMING OF ONSET 17-19Z.
KISP FCSTER COMMENTS: MVFR VSBY POSSIBLE THIS MORNING. AMENDMENTS
MAY BE NEEDED WEDNESDAY MORNING AND AFTERNOON FOR IFR/LIFR VSBY. LOW
TO MEDIUM CHANCE OF VLIFR. STILL SOME UNCERTAINTY...BUT CONFIDENCE
IS INCREASING THAT VSBYS COME DOWN TO LESS THAN 1 MILE. TIMING OF
ONSET 16-18Z.
.OUTLOOK FOR 00Z THU THROUGH SAT...
.LATE WED NIGHT...CONDITIONS IMPROVING TO VFR. W WINDS WITH G20-25KT
THROUGH AROUND 06Z.
.THU-THU EVENING...VFR.
.LATE THU NIGHT-FRI...MVFR OR LOWER CONDITIONS AND LLWS LIKELY IN
RAIN. A TSTM POSSIBLE. LATE DAY OR EVENING COLD FROPA.
.FRI NIGHT-SAT...VFR. W WINDS G20-25KT.
&&
.MARINE...
SCA CONTINUES ON THE OCEAN THROUGH THURSDAY MORNING EAST OF FIRE
ISLAND INLET. OTHERWISE...SCA ON OCEAN WEST OF FIRE ISLAND INLET
THROUGH TONIGHT. MAINLY SUB SCA CONDITIONS ON OTHER WATERS BUT
OCCASIONAL 25 KT GUSTS CANNOT BE RULED OUT TODAY.
SMALL CRAFT SEAS ON THE OCEAN WATERS WILL BE LIKELY THURSDAY NIGHT
INTO FRIDAY AS A SOUTHERLY FLOW INCREASES AHEAD OF A COLD FRONT.
SOUTHERLY WIND SPEEDS AND GUSTS MAY INCREASE TO NEAR SMALL CRAFT
LEVELS LATE THURSDAY NIGHT INTO FRIDAY MORNING. WITH A COLD FRONTAL
PASSAGE FRIDAY AFTERNOON THE WIND SHIFTS TO THE WEST AND DIMINISHES.
SEAS ON THE OCEAN REMAIN AT SMALL CRAFT LEVELS INTO SATURDAY
EVENING.
WIND GUSTS ON THE OCEAN MAY ONCE AGAIN INCREASE TO NEAR SMALL CRAFT
LEVELS SUNDAY NIGHT BEHIND A COLD FRONT MOVING THROUGH THE WATERS
SUNDAY.
&&
.HYDROLOGY...
RAINFALL AMOUNTS OF AROUND A QUARTER TO A THIRD OF AN INCH IS
EXPECTED DURING THE DAY TODAY WITH THE COLD FRONT.
A QUARTER TO HALF INCH OF RAINFALL IS LIKELY THURSDAY NIGHT INTO
FRIDAY.
&&
.EQUIPMENT...
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR NYZ067-069.
NJ...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR NJZ002-004-103-
105-107.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ355.
SMALL CRAFT ADVISORY UNTIL NOON EST THURSDAY FOR ANZ350-353.
&&
$$
SYNOPSIS...JM/MET
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...MET
AVIATION...JP
MARINE...JM/MET
HYDROLOGY...JM/MET
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS ALBANY NY
645 AM EST WED FEB 19 2014
.SYNOPSIS...
ANOTHER FAST MOVING LOW PRESSURE SYSTEM WILL BRING A
PERIOD OF SNOW AND RAIN TO THE REGION THIS AFTERNOON AND EVENING.
MILDER AIR WILL THEN MOVE INTO THE REGION BY THE END OF THE
WEEK...ALONG WITH A CHANCE OF RAIN SHOWERS AS A STRONG COLD FRONT
APPROACHES FROM THE GREAT LAKES THURSDAY NIGHT AND FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 635 AM EST...HAVE RAISED SNOWFALL AMTS ACROSS THE LAKE
GEORGE/SARATOGA REGION...INTO THE BERKSHIRES AND SOUTHERN VT.
EXPECT 1-3 INCHES ACROSS THE LAKE GEORGE/SARATOGA REGION...AND 2-4
INCHES ACROSS SOUTHERN VT...AND ACROSS BERKSHIRE COUNTY. THIS WAS
BASED ON THE LATEST RAP13 AND HRRR...WHICH INDICATED A POSSIBLE
BURST OF CONVECTIVE PRECIPITATION BETWEEN 22Z-02Z ASSOCIATED WITH
THE PASSAGE OF THE UPPER TROUGH.
MEANWHILE...HIGH AND MID LEVEL CLOUDS ARE INCREASING ACROSS
THE REGION. TEMPS...WHICH INITIALLY DROPPED INTO THE SINGLE DIGITS
AND LOWER TEENS DUE TO SIGNIFICANT BOUNDARY LAYER DECOUPLING
ALONG WITH THE VERY DEEP SNOWCOVER...HAVE NOW STARTED TO RISE. WE
EXPECT MOST TEMPS TO RISE INTO THE TEENS TO LOWER 20S BY
SUNRISE...ALTHOUGH MAY STILL REMAIN IN THE LOWER TEENS ACROSS
PORTIONS OF THE UPPER HUDSON VALLEY.
OTHERWISE...WE HAVE A VERY CHALLENGING FORECAST AHEAD FOR
TODAY...AS A POTENT SHORTWAVE CURRENTLY CROSSING THE MIDWEST
TRANSLATES RAPIDLY EASTWARD. THIS FEATURE...IN COMBINATION WITH A
WEAKER LEAD UPPER LEVEL IMPULSE...HAS TRIGGERED CONSIDERABLE
ELEVATED CONVECTION ACROSS THE NORTHERN APPALACHIANS AND UPPER
OHIO VALLEY EARLY THIS MORNING. THE LATEST RAP13 AND HRRR INDICATE
THAT THE REMNANTS OF THIS CONVECTION SHOULD TRACK EAST
NORTHEAST...ACROSS MAINLY CENTRAL AND SOUTHERN PORTIONS OF THE
REGION THIS AFTERNOON. THUS...PRECIP WILL BE MOST FAVORED FOR THE
EASTERN CATSKILLS...NORTHEAST INTO THE CAPITAL
REGION...BERKSHIRES...MID HUDSON VALLEY AND NW CT...AND SOUTHERN
VT...WITH POTENTIALLY LESS TO THE N AND W. HOWEVER...SHOULD THIS
CONVECTION WEAKEN...IT IS POSSIBLE THAT BETTER MOISTURE TRANSPORT
COULD ALLOW FOR PRECIP TO DEVELOP FURTHER NORTHWARD.
FURTHER COMPLICATING THE FORECAST WILL BE THE EXPECTED THERMAL
PROFILES AS THE PRECIP OCCURS. FORECAST SOUNDINGS...ESP SOUTH OF
ALBANY...INDICATE AN ABOVE FREEZING LAYER DEVELOPING AROUND 925
MB. THIS...IN COMBINATION WITH SOME BOUNDARY LAYER WARMING...WOULD
PROMOTE RAIN. HOWEVER...WITH A BURST OF STRONG VERTICAL VELOCITY
AND WET BULB COOLING...THE LOW LEVELS SHOULD COOL SUFFICIENTLY TO
ALLOW FOR SNOW AFTER A PERIOD OF RAIN/SNOW MIX IN SOME VALLEY
AREAS. SO...ASSUMING WE GET INTO THE BETTER DYNAMICAL FORCING THIS
AFTERNOON...WE HAVE SIDED MORE WITH SNOW THAN RAIN FOR MOST AREAS.
THIS SHOULD GIVE MOST VALLEY AREAS FROM ALBANY SOUTHWARD AROUND
AN INCH OF SNOW...WITH 1-3 INCHES POSSIBLE ACROSS PORTIONS OF THE
LAKE GEORGE/SARATOGA REGION...AS WELL AS HIGHER ELEVATIONS
SURROUNDING THE HUDSON VALLEY...AND 2-4 INCHES ACROSS THE
BERKSHIRES AND SOUTHERN VT. AGAIN...THIS IS A VERY TRICKY
SITUATION...AND SHOULD ANY HEAVIER PRECIP LINGER OVER ANY ONE AREA
LONGER THAN EXPECTED...HIGHER SNOWFALL AMTS COULD OCCUR.
HAVE SIDED WITH...OR EVEN COOLER THAN THE COLDER MOS FOR TODAY/S
MAX TEMPS...WITH MID/UPPER 30S IN VALLEY AREAS FROM ALBANY
SOUTH...AND GENERALLY LOWER/MID 30S TO THE NORTH...WITH GENERALLY
20S TO LOWER 30S ACROSS HIGHER ELEVATIONS.
SOUTH TO SOUTHEAST WINDS WILL INCREASE THIS MORNING THROUGH EARLY
AFTERNOON...SIMILAR TO YESTERDAY...WITH SOME GUSTS POSSIBLY
REACHING UP TO 30-35 MPH ACROSS PORTIONS OF SW VT...THE
BERKSHIRES...AND TACONICS...AND POSSIBLY UP TO 25-30 MPH WITHIN
THE CAPITAL REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...AS THE MAIN SHORTWAVE TROUGH PASSES THROUGH...ANOTHER
BURST OF PRECIPITATION IS EXPECTED. THE PRECIP SHOULD BE MORE
SHOWERY IN NATURE. IN FACT...MODEL SOUNDINGS ACTUALLY INDICATE RATHER
STEEP LAPSE RATES IN THE 700-500 HPA LAYER...WITH THE LATEST RAP13
INDICATING AS STEEP AS 8-8.5 C/KM. THESE STEEP LAPSE RATES...COMBINED
WITH ASCENT FROM THE APPROACHING/PASSING SHORTWAVE TROUGH...COULD
EVEN ALLOW FOR SOME ISOLATED THUNDERSTORMS ACROSS THE
REGION...SOME OF WHICH COULD PRODUCE GRAUPEL/SMALL HAIL. IN THE
WAKE OF THE TROUGH PASSAGE...STRONG WEST/NORTHWEST WINDS WILL
LIKELY DEVELOP...WITH ENHANCED FLOW DOWN THE MOHAWK RIVER
VALLEY/CAPITAL REGION AND BERKSHIRES EXPECTED. THIS COULD ALLOW
FOR SOME GUSTS TO REACH 35-40 MPH AT TIMES LATER THIS EVENING
UNTIL SHORTLY AFTER MIDNIGHT. SKIES SHOULD INITIALLY REMAIN MOSTLY
CLOUDY...BUT AS STRONG SUBSIDENCE AND SOME DOWNSLOPING
OCCURS...SKIES SHOULD TREND TO MOSTLY CLEAR WELL AFTER MIDNIGHT.
TEMPS WILL BE TRICKY...AS THERE COULD BE A WINDOW OF RAPID
DECOUPLING RIGHT AROUND OR EVEN AFTER DAYBREAK. HOWEVER...WIND AND
SOME CLOUDS SHOULD KEEP THIS FROM OCCURRING FOR MOST OF THE NIGHT.
SO...ALTHOUGH HAVE SIDED WITH THE COOLER MOS...DID NOT GO MUCH
COOLER. STILL EXPECT WIDESPREAD TEENS AND 20S ACROSS THE REGION.
THURSDAY...HIGH PRESSURE RIDGE WILL TRANSLATE EAST ACROSS THE
REGION. SKIES SHOULD BE MOSTLY SUNNY IN THE MORNING...WITH CLOUDS
INCREASING IN THE AFTERNOON. SOME LIGHT PRECIPITATION COULD REACH
FAR WESTERN AREAS TOWARD OR JUST AFTER SUNSET...MAINLY AS
RAIN...ALTHOUGH A RAIN/SLEET/SNOW MIX COULD OCCUR IN HIGHER
ELEVATIONS. EXPECT MAX TEMPS TO REACH THE UPPER 30S TO LOWER 40S
IN MOST VALLEY AREAS...AND LOWER/MID 30S FOR HIGHER ELEVATIONS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
AS POTENT STORM WRAPS UP ACROSS THE CENTRAL GREAT LAKES
REGION...EQUALLY IMPRESSIVE LOW LEVEL JET AND ISENTROPIC LIFT WILL
UNFOLD ACROSS UPSTATE NEW YORK THURSDAY NIGHT. THIS WILL ALLOW FOR
BANDS OF PRECIPITATION TO EVOLVE FROM SOUTH TO NORTH WITH THE PEAK
OF THE LOW LEVEL FORCING TAKING PLACE ACROSS THE ADIRONDACKS.
THERMAL PROFILES ACROSS THE REGION WILL BE TRANSITIONING WITHIN THE
WARM ADVECTION AS BOUNDARY LAYER TEMPS MAY STRUGGLE FOR A PERIOD OF
TIME. THIS SETS THE STAGE FOR SNOW MIXING WITH SLEET/FREEZING RAIN
IMPACTING MAINLY THE ADIRONDACKS AND SOUTHERN
GREENS...ALTHOUGH...COULD NOT RULE OUT SOME ISOLATED SHELTERED
LOCATIONS RECEIVING A WINTRY MIX IN THE MOHAWK AND CENTRAL-NORTHERN
HUDSON RIVER VALLEY. HOWEVER...THE STRENGTH OF THE WARM ADVECTION
WILL EVENTUALLY OVERCOME THE SHALLOW SUB FREEZING TEMPERATURES
FRIDAY MORNING FOR ALL OF THE PRECIPITATION TO BECOME RAIN.
ALONG WITH THE TEMPERATURES INCREASING...SO DOES THE DEWPOINT TO
ABOVE FREEZING. AS THIS WARMER AND MORE MOIST AIR ADVECTS OVER A
SNOW COVERED GROUND WOULD RESULT IN FOG AS WE WILL PLACE THIS IN THE
GRIDS. STRONG COLD FRONT WITH A FAIRLY TIGHT THERMAL GRADIENT FROM
+8C AT H850 OVER EASTERN NY TO -6C OVER WESTERN NY WILL QUICKLY MOVE
ACROSS THE REGION BY EARLY AFTERNOON PER THE LATEST NCEP MODEL SUITE
TIMING. AN INTERESTING NOTE HERE IS THE SHOWALTER VALUES FROM LATE
MORNING TO EARLY AFTERNOON DROP TO AROUND 0C WHICH SUGGESTS THE
WINDOW OF OPPORTUNITY FOR THUNDER. HOWEVER...WE WILL HOLD OFF ON
THE MENTION IN THE FORECAST/GRIDS UNTIL UPSTREAM TRENDS CAN BE
BETTER OBTAINED.
OVERALL...TEMPERATURES DURING THIS TIME FRAME WILL BE MAINLY
NON-DIURNAL DUE TO THE WARM ADVECTION THURSDAY NIGHT AND CONTINUING
TO RISE THROUGH FRIDAY.
THE LONG TERM WILL FEATURE A RETURN BACK TO WINTER TEMPERATURES AND
A VERY ACTIVE/FAST CYCLONIC FLOW ACROSS THE NORTHEAST CORRIDOR.
THE STORM THAT DEVELOPS OVER THE GREAT LAKES REGION SLOWLY FILLS AND
TRANSITIONS INTO A HUDSON/JAMES BAY LOW. WE WILL BE ON THE SOUTHERN
PERIPHERY OF THIS LOW WHICH KEEPS US RATHER UNSETTLED AND NEAR TO
BELOW NORMAL TEMPERATURES. THE TIMING OF SHORT WAVES WILL BE A
CHALLENGE IN THESE FAST FLOW REGIMES. PER THE GLOBAL MODELS...THE
FIRST WAVE ARRIVES SATURDAY WITH MAINLY THE EASTERN GREAT LAKES AND
SOME LAKE EFFECT SNOW IMPACTING PORTIONS OF THE ADIRONDACKS. THE
NEXT WAVE ARRIVES SUNDAY WITH A BIT MORE OF A SOUTHERN ROUTE. THIS
WAVE ATTEMPTS TO BE AN OVERACHIEVER PER THE ECMWF WITH THE GFS/GGEM
MUCH FLATTER AND MORE PROGRESSIVE. GIVEN THE RECENT TRACK RECORD OF
THE ECMWF...WE WILL PLACE SLIGHT CHANCE POPS FOR NOW.
LOOKING AHEAD INTO THE NEW WORK WEEK...THE HUDSON/JAMES BAY UPPER
LOW LOSES ITS GRIP AS WE MONITOR A POTENT PIECE OF ENERGY DIVE
SOUTHWARD FROM THE NORTHWEST TERRITORIES INTO THE INTERMOUNTAIN
WEST AND QUICKLY OUT ONTO THE CENTRAL PLAINS AND MID WEST BY
TUESDAY. THIS WILL REINTRODUCE THE CHANCE FOR ADDITIONAL WINTRY
PRECIPITATION LATE MONDAY INTO TUESDAY FOR THE ENTIRE CWFA.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
RATHER CHALLENGING IN THE NEAR TERM AS CLEAR SKIES WITH LIGHT WINDS
AND SNOW FROM EARLIER HAS RESULTED IN MVFR/IFR CONDITIONS AT KGFL
WITH OTHER TAF SITES HINTING AT THE POSSIBILITY. WE WILL PLACE A
TEMPO GROUP AT THIS TIME...AS WE MONITOR TRENDS AND UPSTREAM HIGH
AND MID LEVEL CLOUD COVER ADVECTING INTO THE REGION. THIS SHOULD
MINIMIZE THE FOG FROM SPREADING BUT IT WILL BE CLOSE.
AFTER SUNRISE...VISIBILITIES SHOULD IMPROVE AS WE WATCH THE NEXT
CLIPPER SYSTEM APPROACHING. THIS IS EXPECTED TO BRING ANOTHER
CHANCE FOR PRECIPITATION LATE THIS MORNING INTO THE AFTERNOON
HOURS. BOUNDARY LAYER TEMPERATURES WILL BE CLOSE TO RESULT IN
EITHER SN/RASN/RA. FOR NOW...WE FEEL KGFL WILL BE MAINLY SNOW WITH
A MIXTURE FURTHER SOUTH INTO KALB-KPSF AND TRANSITIONING TO ALL RAIN
KPOU. PRECIP SHOULD END THIS EVENING FROM WEST TO EAST RATHER
QUICKLY.
VARIABLE WINDS AT LESS THAN 6 KT WILL SWITCH TO A W-NW DIRECTION
BUT SWITCH TO A SOUTHERLY DIRECTION AND INCREASE TO AROUND 10 KTS
FOR WEDNESDAY MORNING...AND CONTINUE INTO THE AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...FG.
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND ARE GENERALLY FROM A FOOT TO THREE FEET. ALTHOUGH WE HAVE
WARMER TEMPERATURES IN THE FORECAST FOR THE LATTER PART OF THE
WEEK...EXCEPT FOR THURSDAY NIGHT...OVERNIGHT LOWS WILL BE AROUND OR
SLIGHTLY BELOW FREEZING WHICH SHOULD RESULT IN A SLOW MELT AND
HOPEFULLY MINIMIZE ANY FLOOD THREAT. RAINFALL TOTALS THURSDAY NIGHT
INTO FRIDAY MORNING ARE FORECAST TO GENERALLY BE IN THE QUARTER TO
HALF INCH RANGE...SO MUCH OF THIS RAINFALL SHOULD BE ABSORBED BY THE
CURRENT SNOWPACK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 25.7 INCHES THROUGH THE 16TH. THIS AMOUNT IS ONLY 0.3
INCHES FROM REACHING INTO THE TOP 10 FOR SNOWIEST FEBRUARYS SINCE
1885.
A LIGHT TO MODERATE SNOWFALL IS EXPECTED TUESDAY.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.5 INCHES 1899
8. 26.1 INCHES 1914
9. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 62.8 INCHES. NORMAL FOR
THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/GJM
NEAR TERM...KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...BGM/NAS
HYDROLOGY...KL/GJM
CLIMATE...
AREA FORECAST DISCUSSION
NWS ALBANY NY
437 AM EST WED FEB 19 2014
.SYNOPSIS...
ANOTHER FAST MOVING LOW PRESSURE SYSTEM WILL BRING A
PERIOD OF SNOW AND RAIN TO THE REGION THIS AFTERNOON AND EVENING.
MILDER AIR WILL THEN MOVE INTO THE REGION BY THE END OF THE
WEEK...ALONG WITH A CHANCE OF RAIN SHOWERS AS A STRONG COLD FRONT
APPROACHES FROM THE GREAT LAKES THURSDAY NIGHT AND FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 435 AM EST...HIGH AND MID LEVEL CLOUDS ARE INCREASING ACROSS
THE REGION. TEMPS...WHICH INITIALLY DROPPED INTO THE SINGLE DIGITS
AND LOWER TEENS DUE TO SIGNIFICANT BOUNDARY LAYER DECOUPLING
ALONG WITH THE VERY DEEP SNOWCOVER...HAVE NOW STARTED TO RISE. WE
EXPECT MOST TEMPS TO RISE INTO THE TEENS TO LOWER 20S BY
SUNRISE...ALTHOUGH MAY STILL REMAIN IN THE LOWER TEENS ACROSS
PORTIONS OF THE UPPER HUDSON VALLEY.
WE HAVE A VERY CHALLENGING FORECAST AHEAD FOR TODAY...AS A POTENT
SHORTWAVE CURRENTLY CROSSING APPROACHING THE MIDWEST TRANSLATES
RAPIDLY EASTWARD. THIS FEATURE...IN COMBINATION WITH A WEAKER LEAD
UPPER LEVEL IMPULSE...HAS TRIGGERED CONSIDERABLE ELEVATED
CONVECTION ACROSS THE NORTHERN APPALACHIANS AND UPPER OHIO VALLEY
EARLY THIS MORNING. THE LATEST RAP13 AND HRRR INDICATE THAT THE
REMNANTS OF THIS CONVECTION SHOULD TRACK EAST NORTHEAST...ACROSS
MAINLY CENTRAL AND SOUTHERN PORTIONS OF THE REGION THIS AFTERNOON.
THUS...PRECIP WILL BE MOST FAVORED FOR THE EASTERN
CATSKILLS...NORTHEAST INTO THE CAPITAL REGION...BERKSHIRES...MID
HUDSON VALLEY AND NW CT...AND SOUTHERN VT...WITH POTENTIALLY LESS
TO THE N AND W. HOWEVER...SHOULD THIS CONVECTION WEAKEN...IT IS
POSSIBLE THAT BETTER MOISTURE TRANSPORT COULD ALLOW FOR PRECIP TO
DEVELOP FURTHER NORTHWARD.
FURTHER COMPLICATING THE FORECAST WILL BE THE EXPECTED THERMAL
PROFILES AS THE PRECIP OCCURS. FORECAST SOUNDINGS...ESP SOUTH OF
ALBANY...INDICATE AN ABOVE FREEZING LAYER DEVELOPING AROUND 925
MB. THIS...IN COMBINATION WITH SOME BOUNDARY LAYER WARMING...WOULD
PROMOTE RAIN. HOWEVER...WITH A BURST OF STRONG VERTICAL VELOCITY
AND WET BULB COOLING...THE LOW LEVELS SHOULD COOL SUFFICIENTLY TO
ALLOW FOR SNOW AFTER A PERIOD OF RAIN/SNOW MIX IN SOME VALLEY
AREAS. SO...ASSUMING WE GET INTO THE BETTER DYNAMICAL FORCING THIS
AFTERNOON...WE HAVE SIDED MORE WITH SNOW THAN RAIN FOR MOST AREAS.
THIS SHOULD GIVE MOST VALLEY AREAS AROUND AN INCH OF SNOW...WITH
1-3 INCHES POSSIBLE ACROSS HIGHER ELEVATIONS SURROUNDING THE
HUDSON VALLEY...ESPECIALLY ACROSS THE BERKSHIRES AND SOUTHERN VT.
AGAIN...THIS IS A VERY TRICKY SITUATION...AND SHOULD ANY HEAVIER
PRECIP LINGER OVER ANY ONE AREA LONGER THAN EXPECTED...HIGHER
SNOWFALL AMTS COULD OCCUR.
HAVE SIDED WITH...OR EVEN COOLER THAN THE COLDER MOS FOR TODAY/S
MAX TEMPS...WITH MID/UPPER 30S IN VALLEY AREAS FROM ALBANY
SOUTH...AND GENERALLY LOWER/MID 30S TO THE NORTH...WITH GENERALLY
20S TO LOWER 30S ACROSS HIGHER ELEVATIONS.
SOUTH TO SOUTHEAST WINDS WILL INCREASE THIS MORNING THROUGH EARLY
AFTERNOON...SIMILAR TO YESTERDAY...WITH SOME GUSTS POSSIBLY
REACHING UP TO 30-35 MPH ACROSS PORTIONS OF SW VT...THE
BERKSHIRES...AND TACONICS...AND POSSIBLY UP TO 25-30 MPH WITHIN
THE CAPITAL REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...AS THE MAIN SHORTWAVE TROUGH PASSES THROUGH...ANOTHER
BURST OF PRECIPITATION IS EXPECTED. THE PRECIP SHOULD BE MORE
SHOWERY IN NATURE. IN FACT...MODEL SOUNDINGS ACTUALLY INDICATE RATHER
STEEP LAPSE RATES IN THE 700-500 HPA LAYER...WITH THE LATEST RAP13
INDICATING AS STEEP AS 8-8.5 C/KM. THESE STEEP LAPSE RATES...COMBINED
WITH ASCENT FROM THE APPROACHING/PASSING SHORTWAVE TROUGH...COULD
EVEN ALLOW FOR SOME ISOLATED THUNDERSTORMS ACROSS THE
REGION...SOME OF WHICH COULD PRODUCE GRAUPEL/SMALL HAIL. IN THE
WAKE OF THE TROUGH PASSAGE...STRONG WEST/NORTHWEST WINDS WILL
LIKELY DEVELOP...WITH ENHANCED FLOW DOWN THE MOHAWK RIVER
VALLEY/CAPITAL REGION AND BERKSHIRES EXPECTED. THIS COULD ALLOW
FOR SOME GUSTS TO REACH 35-40 MPH AT TIMES LATER THIS EVENING
UNTIL SHORTLY AFTER MIDNIGHT. SKIES SHOULD INITIALLY REMAIN MOSTLY
CLOUDY...BUT AS STRONG SUBSIDENCE AND SOME DOWNSLOPING
OCCURS...SKIES SHOULD TREND TO MOSTLY CLEAR WELL AFTER MIDNIGHT.
TEMPS WILL BE TRICKY...AS THERE COULD BE A WINDOW OF RAPID
DECOUPLING RIGHT AROUND OR EVEN AFTER DAYBREAK. HOWEVER...WIND AND
SOME CLOUDS SHOULD KEEP THIS FROM OCCURRING FOR MOST OF THE NIGHT.
SO...ALTHOUGH HAVE SIDED WITH THE COOLER MOS...DID NOT GO MUCH
COOLER. STILL EXPECT WIDESPREAD TEENS AND 20S ACROSS THE REGION.
THURSDAY...HIGH PRESSURE RIDGE WILL TRANSLATE EAST ACROSS THE
REGION. SKIES SHOULD BE MOSTLY SUNNY IN THE MORNING...WITH CLOUDS
INCREASING IN THE AFTERNOON. SOME LIGHT PRECIPITATION COULD REACH
FAR WESTERN AREAS TOWARD OR JUST AFTER SUNSET...MAINLY AS
RAIN...ALTHOUGH A RAIN/SLEET/SNOW MIX COULD OCCUR IN HIGHER
ELEVATIONS. EXPECT MAX TEMPS TO REACH THE UPPER 30S TO LOWER 40S
IN MOST VALLEY AREAS...AND LOWER/MID 30S FOR HIGHER ELEVATIONS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
AS POTENT STORM WRAPS UP ACROSS THE CENTRAL GREAT LAKES
REGION...EQUALLY IMPRESSIVE LOW LEVEL JET AND ISENTROPIC LIFT WILL
UNFOLD ACROSS UPSTATE NEW YORK THURSDAY NIGHT. THIS WILL ALLOW FOR
BANDS OF PRECIPITATION TO EVOLVE FROM SOUTH TO NORTH WITH THE PEAK
OF THE LOW LEVEL FORCING TAKING PLACE ACROSS THE ADIRONDACKS.
THERMAL PROFILES ACROSS THE REGION WILL BE TRANSITIONING WITHIN THE
WARM ADVECTION AS BOUNDARY LAYER TEMPS MAY STRUGGLE FOR A PERIOD OF
TIME. THIS SETS THE STAGE FOR SNOW MIXING WITH SLEET/FREEZING RAIN
IMPACTING MAINLY THE ADIRONDACKS AND SOUTHERN
GREENS...ALTHOUGH...COULD NOT RULE OUT SOME ISOLATED SHELTERED
LOCATIONS RECEIVING A WINTRY MIX IN THE MOHAWK AND CENTRAL-NORTHERN
HUDSON RIVER VALLEY. HOWEVER...THE STRENGTH OF THE WARM ADVECTION
WILL EVENTUALLY OVERCOME THE SHALLOW SUB FREEZING TEMPERATURES
FRIDAY MORNING FOR ALL OF THE PRECIPITATION TO BECOME RAIN.
ALONG WITH THE TEMPERATURES INCREASING...SO DOES THE DEWPOINT TO
ABOVE FREEZING. AS THIS WARMER AND MORE MOIST AIR ADVECTS OVER A
SNOW COVERED GROUND WOULD RESULT IN FOG AS WE WILL PLACE THIS IN THE
GRIDS. STRONG COLD FRONT WITH A FAIRLY TIGHT THERMAL GRADIENT FROM
+8C AT H850 OVER EASTERN NY TO -6C OVER WESTERN NY WILL QUICKLY MOVE
ACROSS THE REGION BY EARLY AFTERNOON PER THE LATEST NCEP MODEL SUITE
TIMING. AN INTERESTING NOTE HERE IS THE SHOWALTER VALUES FROM LATE
MORNING TO EARLY AFTERNOON DROP TO AROUND 0C WHICH SUGGESTS THE
WINDOW OF OPPORTUNITY FOR THUNDER. HOWEVER...WE WILL HOLD OFF ON
THE MENTION IN THE FORECAST/GRIDS UNTIL UPSTREAM TRENDS CAN BE
BETTER OBTAINED.
OVERALL...TEMPERATURES DURING THIS TIME FRAME WILL BE MAINLY
NON-DIURNAL DUE TO THE WARM ADVECTION THURSDAY NIGHT AND CONTINUING
TO RISE THROUGH FRIDAY.
THE LONG TERM WILL FEATURE A RETURN BACK TO WINTER TEMPERATURES AND
A VERY ACTIVE/FAST CYCLONIC FLOW ACROSS THE NORTHEAST CORRIDOR.
THE STORM THAT DEVELOPS OVER THE GREAT LAKES REGION SLOWLY FILLS AND
TRANSITIONS INTO A HUDSON/JAMES BAY LOW. WE WILL BE ON THE SOUTHERN
PERIPHERY OF THIS LOW WHICH KEEPS US RATHER UNSETTLED AND NEAR TO
BELOW NORMAL TEMPERATURES. THE TIMING OF SHORT WAVES WILL BE A
CHALLENGE IN THESE FAST FLOW REGIMES. PER THE GLOBAL MODELS...THE
FIRST WAVE ARRIVES SATURDAY WITH MAINLY THE EASTERN GREAT LAKES AND
SOME LAKE EFFECT SNOW IMPACTING PORTIONS OF THE ADIRONDACKS. THE
NEXT WAVE ARRIVES SUNDAY WITH A BIT MORE OF A SOUTHERN ROUTE. THIS
WAVE ATTEMPTS TO BE AN OVERACHIEVER PER THE ECMWF WITH THE GFS/GGEM
MUCH FLATTER AND MORE PROGRESSIVE. GIVEN THE RECENT TRACK RECORD OF
THE ECMWF...WE WILL PLACE SLIGHT CHANCE POPS FOR NOW.
LOOKING AHEAD INTO THE NEW WORK WEEK...THE HUDSON/JAMES BAY UPPER
LOW LOSES ITS GRIP AS WE MONITOR A POTENT PIECE OF ENERGY DIVE
SOUTHWARD FROM THE NORTHWEST TERRITORIES INTO THE INTERMOUNTAIN
WEST AND QUICKLY OUT ONTO THE CENTRAL PLAINS AND MID WEST BY
TUESDAY. THIS WILL REINTRODUCE THE CHANCE FOR ADDITIONAL WINTRY
PRECIPITATION LATE MONDAY INTO TUESDAY FOR THE ENTIRE CWFA.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
RATHER CHALLENGING IN THE NEAR TERM AS CLEAR SKIES WITH LIGHT WINDS
AND SNOW FROM EARLIER HAS RESULTED IN MVFR/IFR CONDITIONS AT KGFL
WITH OTHER TAF SITES HINTING AT THE POSSIBILITY. WE WILL PLACE A
TEMPO GROUP AT THIS TIME...AS WE MONITOR TRENDS AND UPSTREAM HIGH
AND MID LEVEL CLOUD COVER ADVECTING INTO THE REGION. THIS SHOULD
MINIMIZE THE FOG FROM SPREADING BUT IT WILL BE CLOSE.
AFTER SUNRISE...VISIBILITIES SHOULD IMPROVE AS WE WATCH THE NEXT
CLIPPER SYSTEM APPROACHING. THIS IS EXPECTED TO BRING ANOTHER
CHANCE FOR PRECIPITATION LATE THIS MORNING INTO THE AFTERNOON
HOURS. BOUNDARY LAYER TEMPERATURES WILL BE CLOSE TO RESULT IN
EITHER SN/RASN/RA. FOR NOW...WE FEEL KGFL WILL BE MAINLY SNOW WITH
A MIXTURE FURTHER SOUTH INTO KALB-KPSF AND TRANSITIONING TO ALL RAIN
KPOU. PRECIP SHOULD END THIS EVENING FROM WEST TO EAST RATHER
QUICKLY.
VARIABLE WINDS AT LESS THAN 6 KT WILL SWITCH TO A W-NW DIRECTION
...BUT SWITCH TO A SOUTHERLY DIRECTION AND INCREASE TO AROUND 10 KTS
FOR WEDNESDAY MORNING...AND CONTINUE INTO THE AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...FG.
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND ARE GENERALLY FROM A FOOT TO THREE FEET. ALTHOUGH WE HAVE
WARMER TEMPERATURES IN THE FORECAST FOR THE LATTER PART OF THE
WEEK...EXCEPT FOR THURSDAY NIGHT...OVERNIGHT LOWS WILL BE AROUND OR
SLIGHTLY BELOW FREEZING WHICH SHOULD RESULT IN A SLOW MELT AND
HOPEFULLY MINIMIZE ANY FLOOD THREAT. RAINFALL TOTALS THURSDAY NIGHT
INTO FRIDAY MORNING ARE FORECAST TO GENERALLY BE IN THE QUARTER TO
HALF INCH RANGE...SO MUCH OF THIS RAINFALL SHOULD BE ABSORBED BY THE
CURRENT SNOWPACK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 25.7 INCHES THROUGH THE 16TH. THIS AMOUNT IS ONLY 0.3
INCHES FROM REACHING INTO THE TOP 10 FOR SNOWIEST FEBRUARYS SINCE
1885.
A LIGHT TO MODERATE SNOWFALL IS EXPECTED TUESDAY.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.5 INCHES 1899
8. 26.1 INCHES 1914
9. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 62.8 INCHES. NORMAL FOR
THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/GJM
NEAR TERM...KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...BGM/NAS
HYDROLOGY...KL/GJM
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
357 AM EST WED FEB 19 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS OUR REGION THIS AFTERNOON. A WARM FRONT
IS FORECAST TO ARRIVE LATER THURSDAY NIGHT, THEN A STRONG COLD FRONT
SWEEPS ACROSS OUR AREA FRIDAY. ANOTHER COLD FRONT SHOULD CROSS THE
MID ATLANTIC REGION SATURDAY NIGHT AND EARLY SUNDAY. A STRONG HIGH
PRESSURE SYSTEM BUILDING DOWN INTO THE NORTHERN PLAINS LATER SUNDAY
INTO MONDAY, WILL THEN EXPAND EASTWARD TO THE MID ATLANTIC REGION
INTO TUESDAY. AN AREA OF LOW PRESSURE HOWEVER MAY TRACK NEARBY
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK HIGH PRESSURE WAS MOVG AWAY FROM THE REGION. AS IT DOES, A
WEAK CDFNT WILL APPROACH FROM THE W. THIS FRONT WILL PASS THROUGH
THE REGION DURG THE LATE MRNG OR ERLY AFTN BUT WILL NOT BRING MUCH
IN THE WAY OF COLDER TEMPS. WHAT THE FRONT WILL BRING IS SOME
PRECIP AND HERE LIES THE CHALLENGE.
THE LATEST WIDE VIEW OF THE RADAR SHOWED THE NEAREST PRECIP BACK
NEAR THE OH/WV/KY BORDER AND SOME IN WRN NC. THE HRRR SEEMS TO BE
HANDLING THIS WELL. THE PRECIP ADVANCES NEWD, BUT HAS SOME DISTANCE
TO TRAVEL BEFORE IT GETS HERE. ITS ARRIVAL TIME IS PROBABLY A BIT
LATER NOW THAN ORIGINALLY THOUGHT. TEMPS ARE STARTING OUT VERY COLD
THIS MRNG BUT WILL RISE WELL INTO THE 40S FROM THE I-95 CORRIDOR S
AND E, AND INTO THE 50S OVER SRN AND ERN PORTIONS OF THE AREA.
HIGHS ARE EXPECTED TO BE AROUND 40 OR IN THE LOW 40S N AND W. SO
ITS A QUESTION OF WHAT HAPPENS FIRST...DO THE TEMPS RISE ABOVE
FREEZING (AND HOW LOW DO THEY GET BEFOREHAND) ESPECIALLY N AND W OR
DOES THE PRECIP GET HERE FIRST?
IF THE PRECIP ARRIVES FIRST IN THE NRN AND WRN AREAS THEN THE
FREEZING RAIN THREAT IS STILL PRESENT. HOWEVER, THE LATER THE
PRECIP ARRIVES, THE LESSER THE THREAT. THE FURTHER S AND E, THE
LESSER THE THREAT. SO, FOR NOW, WILL LET THE FREEZING RAIN ADVISORY
RIDE, BUT MAY BE ABLE TO CANCEL PORTIONS OF IT WITH THE NEXT UPDATE
DEPENDING ON WHERE THE PRECIP IS AND TEMPS ARE AT THAT TIME. IF THE
GUID IS CORRECT WITH 14-15Z ARRIVAL TIME OF THE PRECIP, THEN MANY
AREAS MAY BE OUT OF THE WOODS AND JUST SEE PLAIN RAIN. WE`LL WAIT
AND SEE.
REGARDLESS, ALL AREAS WILL SEE PLAIN RAIN THRU THE AFTN HOURS WITH A
TAPERING BY EVE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
HIGH PRES WILL BUILD IN BEHIND THE FRONT TONIGHT AND EXPECT A CLEAR
SKY WITH LESSENING WIND. THE FACT THAT THERE WILL BE SOME WIND
WOULD PRECLUDE GOOD RADIATIONAL COOLING CONDS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE OVERALL SYNOPTIC SETUP IS COMPRISED OF AN AMPLIFIED FLOW WITH A
STRONG TROUGH FROM THE MIDWEST TO THE SOUTHERN PLAINS THURSDAY. A
PORTION OF THIS TROUGH SLIDES ACROSS THE NORTHEAST FRIDAY, HOWEVER
THE MAIN TROUGH REMAINS FROM THE PLAINS ON EASTWARD THROUGH THE
WEEKEND. THIS IS COURTESY OF A CLOSED LOW BECOMING ANCHORED NEAR THE
HUDSON BAY REGION. THIS WILL ALLOW THE FLOW TO PUSH A FEW SYSTEMS
OUR WAY, WITH THE MOST NOTABLE ONE SCHEDULED FOR FRIDAY. OVERALL, A
MILDER TIME FRAME IS EXPECTED THROUGH AT LEAST SATURDAY THEN SOME
COOLING TAKES PLACE. A MORE SUBSTANTIAL CHANGE TO COLDER WEATHER
ONCE AGAIN LOOKS TO TAKE PLACE NEXT WEEK. WE GENERALLY USED A MODEL
BLEND THURSDAY INTO SATURDAY, THEN LEANED MORE TOWARD THE 00Z WPC
GUIDANCE AND CONTINUITY.
FOR THURSDAY...HIGH PRESSURE TO OUR EAST WILL DRIVE AN INCREASING
SOUTHERLY FLOW ACROSS THE AREA. AS AN UPPER-LEVEL TROUGH AMPLIFIES
TO OUR WEST, LOW PRESSURE WILL DEEPEN AND TRACK UP ACROSS THE GREAT
LAKES. THIS INCREASING FLOW DOWNSTREAM WILL ALLOW FOR INCREASING WAA
FOR OUR AREA. AS A RESULT, CLOUDS WILL BE ON THE INCREASE DURING THE
DAY. THE INCREASING FLOW WILL ALSO ALLOW HIGHER DEW POINTS TO ADVECT
NORTHWARD, ESPECIALLY AS A WARM FRONT GRADUALLY LIFTS NORTHWARD.
DESPITE THE STRONGER FLOW ALOFT, MANY INLAND AREAS ESPECIALLY SHOULD
BE ABLE TO REMAIN DECOUPLED PARTICULARLY WHERE A DECENT SNOWCOVER
REMAINS. THIS SHOULD LEAD TO SOME FOG DEVELOPING AT NIGHT, AND SOME
COULD BE LOCALLY DENSE. THE INITIAL SURGE IN WAA MAY ALLOW FOR SOME
RAIN IN THE AFTERNOON NEAR OUR FAR WESTERN ZONES, THEN WAA AND A
STRENGTHENING INVERSION COMBINED WITH MOISTENING LOW LEVELS MAY
RESULT IN A BIT OF LIGHT RAIN AND DRIZZLE AT NIGHT. THIS IS MAINLY
AIMED AT OUR NORTHERN ZONES WHERE THE BETTER ISENTROPIC LIFT SLIDES
NORTHWARD. IT WILL BE COLDER ALONG THE ATLANTIC COAST GIVEN THE FLOW
OFF OF THE ATLANTIC WHERE THE OCEAN WATER TEMPERATURES ARE IN THE
30S.
FOR FRIDAY...AN INTENSE SURFACE LOW IS FORECAST TO TRACK TOWARDS THE
HUDSON BAY REGION. THIS STORM IS EXPECTED TO OCCLUDE WITH OUR AREA
IN THE WARM SECTOR UNTIL A STRONG COLD FRONT SWEEPS THROUGH IN THE
AFTERNOON. AHEAD OF THE COLD FRONT, THE 850 MB AND 925 MB FLOW IS
FORECAST TO BE ABOUT 50-70 KNOTS. DESPITE THE ROBUST FLOW, THE
FORECAST SOUNDINGS OVERALL INDICATE THE AIRMASS BECOMING DEEPLY
SATURATED WHICH WOULD HOLD DOWN THE INSTABILITY. THE SOUTHERLY FLOW
MAY TEND TO KEEP SOME COOLER AIR IN PLAY ESPECIALLY CLOSER TO THE
COAST GIVEN THE OCEAN WATER TEMPERATURES IN THE 30S. THE COLD FRONT
ITSELF IS STRONG AND THERE APPEARS TO BE A RIBBON OF LINEAR FRONTAL
FORCING, WHICH MAY RESULT IN A FAST MOVING LOW-TOPPED CONVECTIVE
LINE WITH LITTLE OR NO LIGHTNING. THE VERTICAL EXTENT AND LIGHTNING
WITH ANY CONVECTION WILL BE GOVERNED BY THE AMOUNT OF INSTABILITY
REALIZED. THERE IS THE POTENTIAL FOR LOCALLY STRONG/DAMAGING WINDS
WITH ANY ORGANIZED CONVECTIVE ELEMENTS, ESPECIALLY IF ANY LINEAR
SEGMENTS SURGE FORWARD/BOW GIVEN THE ROBUST AND DEEP SOUTHWESTERLY
FLOW.
OTHERWISE, A BAND OF HEAVY SHOWERS WILL ROLL ACROSS THE REGION WITH
THE POTENTIAL FOR BRIEF BUT LOCAL DOWNPOURS. ONCE THE FRONT SHIFTS
EAST, SHOWERS ARE EXPECTED TO QUICKLY END FROM WEST TO EAST IN THE
AFTERNOON. THERE IS SOME CONCERN ABOUT THE DEGREE OF SURFACE WARMING
ESPECIALLY FROM ABOUT THE LEHIGH VALLEY ON NORTHWARD DUE TO A DEEPER
SNOWPACK THAT SHOULD STILL BE IN PLACE AND MIXING UNCERTAINTIES
/850 MB TEMPERATURES ARE FORECAST TO SURGE TO ABOUT +10 TO +12C
AHEAD OF THE FRONT/. EVEN WITHOUT THUNDER, THERE IS THE POTENTIAL
FOR GUSTY GRADIENT WINDS ESPECIALLY ACROSS THE DELMARVA AND INTO
SOUTHERN NEW JERSEY WHERE BETTER MIXING MAY BECOME ESTABLISHED FOR A
TIME.
FOR SATURDAY AND SUNDAY...A POTENT SURFACE LOW NEAR THE HUDSON BAY
AREA IS FORECAST TO GRADUALLY SPIN DOWN AS IT SHIFTS EASTWARD DURING
THIS TIME FRAME. SOME ADDITIONAL ENERGY THOUGH WITHIN THE TROUGH
ALONG THE SOUTHERN PERIPHERY MAY SEND ANOTHER COLD FRONT THROUGH OUR
AREA LATER SATURDAY NIGHT AND SUNDAY MORNING. THIS BOUNDARY MAY HAVE
A WEAK SURFACE LOW ALONG IT AS THE WESTERLY FLOW HELPS TO ORGANIZE A
WEAK PRESSURE TROUGH EAST OF THE MOUNTAINS. OVERALL, THIS FEATURE
GENERALLY LOOKS TO BE ON THE WEAKER SIDE WITH LIMITED MOISTURE TO
WORK WITH. AS A RESULT, WE FOLLOWED WPC`S LEAD AND WENT WITH A DRY
FORECAST ATTM. WE DID HOWEVER INCREASE THE CLOUDS A BIT MORE
ESPECIALLY LATER SATURDAY NIGHT AND SUNDAY.
FOR MONDAY AND TUESDAY...THE UPPER-LEVEL FLOW MAY BEGIN TO AMPLIFY
ONCE AGAIN IN A WAY THAT DRIVES COLDER AIR INTO THE EASTERN STATES.
THIS COULD BE INTRODUCED BY A LEAD SHORT WAVE THAT SPAWNS A SURFACE
LOW NEAR THE MID ATLANTIC, OR PERHAPS A CLIPPER TYPE SYSTEM THAT MAY
THEN REDEVELOP OFF THE MID ATLANTIC COAST. THIS APPEARS TO BE
POSSIBLE DURING TUESDAY WITH THE CHC OF SOME SNOW AS THE AIRMASS
GETS COLDER. THEREFORE, WENT DRY FOR MONDAY THEN LOW CHC POPS
TUESDAY WITH HIGHS A LITTLE COLDER. OUR CONFIDENCE REGARDING THE
TIMING AND DETAILS THIS FAR OUT IS LOW, HOWEVER THERE ARE SOME SIGNS
OF A RETURN TO COLDER AIR ALONG WITH CHCS OF SOME SNOW.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THERE IS SOME FOG CAUSING LCL MVFR CONDS THIS MRNG OTHERWISE MOST
SITES ARE VFR. THEY WILL REMAIN VFR UNTIL PRECIP MOVES IN LATER
THIS MRNG. THEN MVFR/IFR CONDS WILL PREVAIL THRU LATE AFTN. A
FRONT WILL THEN CROSS THE REGION AND END THE PRECIP BY LATE AFTN AND
BRING A RETURN TO VFR CONDS. VFR CONDS WILL THEN BE THE RULE FOR
THE REMAINDER OF THE TAF PD. THERE COULD BE SOME FZRA AT THE ONSET
FOR KABE AND KRDG DEPENDING ON THE TIME THE PRECIP ARRIVES, BEFORE A
CHANGEOVER TO RA. EVERYWHERE ELSE WILL SEE PLAIN RAIN. WIND WILL
BE SE TO S TODAY GENLY AROUND 10 KT THEN BECOME WLY 10 TO 15 KT
EARLY TONIGHT BEHIND THE FROPA BEFORE DECREASING LATE.
OUTLOOK...
THURSDAY...VFR DURING THE DAY WITH AN INCREASE IN CLOUDS. THE
CONDITIONS THEN DETERIORATE AT NIGHT TO MVFR/IFR DUE TO STRATUS
AND/OR FOG. THERE IS THE POTENTIAL FOR SOME DRIZZLE OR LIGHT RAIN
AT NIGHT. A WARM FRONT LIFTING NORTH ACROSS OUR AREA AT NIGHT MAY
RESULT IN A PERIOD OF LOW-LEVEL WIND SHEAR, AS SOUTHWESTERLY FLOW
AT 2,000 FEET INCREASES TO NEAR 50 KNOTS ESPECIALLY LATE.
FRIDAY...MVFR/IFR DUE TO STRATUS AND/OR FOG IN THE MORNING WITH
PERHAPS SOME LIGHT RAIN OR DRIZZLE. LOW-LEVEL WIND SHEAR IS POSSIBLE
IN THE MORNING WITH SOUTHWESTERLY FLOW AT 2,000 FEET AROUND 50
KNOTS. A STRONG COLD FRONT SWEEPS ACROSS THE AREA DURING THE
AFTERNOON. A BAND OF SHOWERS AND PERHAPS SOME THUNDERSTORMS SHOULD
ACCOMPANY THE FRONT. SOUTHWEST WINDS 10-20 KNOTS AHEAD OF THE FRONT
MAY BE RATHER GUSTY ESPECIALLY WITH ANY HEAVIER SHOWERS OR A
THUNDERSTORM, THEN SHIFT TO THE NORTHWEST FOLLOWING THE COLD FRONT.
A RETURN TO VFR IS EXPECTED FOLLOWING THE COLD FRONTAL PASSAGE.
SATURDAY AND SUNDAY...OVERALL VFR.
&&
.MARINE...
WILL LET THE CURRENT SCA FLAG CONTINUE AS PREV ISSUED AS WIND AND
SEAS ARE EXPECTED TO INCREASE AS A CDFNT APPROACHES THE WATERS AND
THEN CROSSES THEM LATER TODAY. HIGH PRESSURE WILL THEN BUILD IN
BEHIND THE FRONT AND THE WIND AND SEAS SHOULD GRADUALLY SUBSIDE.
OUTLOOK...
THURSDAY...SUB-ADVISORY CONDITIONS DURING THE DAY, THEN WINDS AND
SEAS INCREASE AT NIGHT AS A WARM FRONT LIFTS NORTH AND A COLD FRONT
APPROACHES FROM THE WEST. THE AIRMASS WILL BE WARMING, THEREFORE
VERTICAL MIXING SHOULD BE LIMITED IN GENERAL OVER THE COLD WATER.
FRIDAY...SMALL CRAFT ADVISORY CONDITIONS EXPECTED. A SOUTHERLY FLOW
AHEAD OF A STRONG COLD FRONT WILL SHIFT TO THE NORTHWEST IN ITS WAKE
DURING THE AFTERNOON. THE 925 MB WINDS ARE FORECAST TO BE ABOUT 70
KNOTS AHEAD OF THE FRONT, THEREFORE IF MIXING CAN BE EFFICIENT
ENOUGH A PERIOD OF GALES WILL BE POSSIBLE. IN ADDITION, SOME
THUNDERSTORMS ARE POSSIBLE WITH EVEN THE CHC OF A LOW-TOPPED
CONVECTIVE LINE. THE WINDS AND SEAS ARE ANTICIPATED TO SUBSIDE AT
NIGHT.
SATURDAY AND SUNDAY...THE CONDITIONS SHOULD BE BELOW ADVISORY
CRITERIA SATURDAY AS A WEAKNESS IN THE PRESSURE FIELDS OCCUR. THE
CAA IS FORECAST TO INCREASE DURING SUNDAY, AND THIS MAY RESULT IN
WINDS INCREASING TO NEAR ADVISORY CRITERIA ESPECIALLY LATE.
&&
.HYDROLOGY...
CURRENT CONDITIONS...THE EXISTING SNOWPACK ON THE GROUND CONTAINS
3.0 TO 4.5 INCHES OF WATER OVER NORTHERN NEW JERSEY AND EASTERN
PENNSYLVANIA. 1.5 TO 3.0 INCHES OF WATER EXISTS WITHIN THE
SNOWPACK ACROSS CENTRAL NEW JERSEY. THERE ARE 1.5 INCHES OR LESS
OF WATER EQUIVALENT ACROSS SOUTHERN NEW JERSEY AND THE DELMARVA.
IN ADDITION, QUITE A FEW RIVERS AND LARGE STREAMS IN THE AREA
REMAIN ICE-COVERED IN SPOTS DUE TO THE SUSTAINED COLD TEMPERATURES
WE`VE BEEN EXPERIENCING SINCE DECEMBER. THIS COMBINATION OF STORED
WATER IN THE SNOWPACK AND ICE-COVERED WATERWAYS RAISES THE CONCERN
FOR POTENTIAL FLOODING.
PREDICTABILITY...SNOWMELT ALONE USUALLY DOESN`T CAUSE FLOODING IN
THIS PART OF THE COUNTRY. HOWEVER, GIVEN THAT THERE`S SO MUCH ICE IN
THE RIVERS THIS YEAR, THE WATER MELTING FROM THE SNOWPACK COULD
INCREASE THE FLOW TO SUCH AN EXTENT THAT THE ICE WILL BREAK AND JAMS
WILL FORM. ICE JAMS ARE NOT PREDICTABLE ALTHOUGH WE KNOW WHEN
TEMPERATURES WARM AND WATER LEVELS RISE, THEY ARE POSSIBLE.
SO, WHEN AND WHERE ICE JAMS MAY OCCUR ARE DIFFICULT TO PINPOINT,
ALTHOUGH MANY RIVERS AND STREAMS DO HAVE FAVORED SPOTS (BENDS IN THE
STREAM, BRIDGE ABUTMENTS, PIERS, THE HEAD OF A TIDE). SOMETIMES JAMS
DEVELOP AND DISSIPATE WITHOUT PROBLEMS, BUT SOMETIMES THEY CAUSE
MAJOR PROBLEMS. IF HEAVY RAIN OCCURS ON TOP OF A RIPE SNOWPACK (A
SNOWPACK JUST BEGINNING TO SHED WATER DUE TO MELT), THE COMBINATION
OF ADDED WATER PLUS WARMTH, WILL ACCELERATE THE MELTING PROCESS AND
INCREASE FLOODING CONCERNS. LARGE SNOWPACKS CAN MELT VERY QUICKLY
WHEN WARM, MOIST AIR MOVES OVER THEM AND RAIN FALLS ON TOP OF THEM.
THE JANUARY 1996 FLOOD EVENT AND THE APRIL 2005 EVENT SERVES AS
EXAMPLES. GUSTY WINDS COULD ALSO HELP TO ACCELERATE MELTING.
FORECAST...A WARM SPELL LASTING SEVERAL DAYS IS EXPECTED FROM TODAY
THROUGH SATURDAY, WHICH WILL SERVE TO SOFTEN AND MELT THE SNOWPACK.
SIGNIFICANT WIDESPREAD RAIN IS NOT EXPECTED THIS WEEK, ALTHOUGH SOME
THUNDERSTORMS ON FRIDAY COULD PRODUCE AN INCH OR SO OF RAIN IN A
VERY SHORT PERIOD OF TIME IN ISOLATED SPOTS. THE WARM TEMPERATURES
WILL ALSO SOFTEN THE RIVER ICE, MAKING IT EASIER TO BREAK.
WE NEED TO KEEP AN EYE ON ALL THESE ELEMENTS, WARMING TEMPERATURES,
MELTING SNOWPACK, MELTING RIVER ICE, AND RAIN, BUT IT DOESN`T APPEAR
AT THIS VANTAGE POINT THAT THE COMBINED EFFECT OF ALL OF THESE
ELEMENTS WILL BE SEVERE ENOUGH TO CAUSE WIDESPREAD MAINSTEM RIVER
AND/OR LARGE STREAM FLOODING AT THE END OF THIS WEEK. A BIGGER ISSUE
WILL LIKELY BE STREET AND POOR DRAINAGE FLOODING DUE TO CLOGGED OR
RESTRICTED DRAINS, AS WELL AS SMALL CREEK AND STREAM FLOODING, THE
ONES THAT RESPOND MORE QUICKLY.
BUT EVENTUALLY, THE SNOW AND ICE WILL GO, IF NOT THIS WEEK, THAN
SOMETIME LATER THIS WINTER OR EARLY SPRING, AND HOPEFULLY AT A
METERED PACE. WE NEED TO BE VIGILANT FOR THE SIGNS OF FLOODING AS WE
MOVE FORWARD.
&&
.CLIMATE...
SEASONAL SNOW TOTALS AND RANKING SO FAR...
PHILADELPHIA...58.4 INCHES, WHICH RANKS #3. OFFICIAL RECORDS DATE
BACK TO 1872.
1. 78.7 2009-10
2. 65.5 1995-96
3. 58.4 2013-14
4. 55.4 1898-99
ALLENTOWN...66.7 INCHES, WHICH RANKS #4. OFFICIAL RECORDS DATE BACK
TO 1922.
1. 75.4 1993-94
2. 71.4 1995-96
3. 67.2 1966-67
4. 66.7 2013-14
5. 65.2 1960-61
WILMINGTON...47.9 INCHES, WHICH RANKS #4. OFFICIAL RECORDS DATE BACK
TO 1894.
1. 72.8 2009-10
2. 49.5 1957-58
3. 48.8 1906-07 (MISSING DAYS)
4. 47.9 2013-14
5. 46.1 2002-03
ATLANTIC CITY...27.5 INCHES, WHICH IS RANKED #18. OFFICIAL RECORDS
DATE BACK TO 1874.
FOR THE MONTH OF FEBRUARY...
PHILADELPHIA AT 21.3 INCHES, RANKED #7.
1. 51.5 2010
2. 31.5 1899
3. 29.6 2003
4. 27.6 1979
5. 26.1 1983
6. 24.1 1907
7. 21.3 2014
8. 19.0 1978
9/10 18.5 1967 AND 1934
ALLENTOWN AT 36.5 INCHES, RANKED #2 BEHIND THE 42.9 INCHES OF 2010.
WILMINGTON AT 18.5 INCHES, RANKED TIED #7 BEHIND THE #1 46.9 INCHES
OF 2010.
1. 46.9 2010
2. 31.6 2003
3. 27.6 1979
4. 26.3 1934 (MISSING 18 DAYS)
5 22.6 1895 (MISSING 21 DAYS)
6. 18.7 1967
7/8. 18.5 2014 AND 1983
9. 18.4 1978
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZING RAIN ADVISORY FROM 7 AM THIS MORNING TO NOON EST
TODAY FOR PAZ054-055-060>062.
FREEZING RAIN ADVISORY FROM 7 AM TO 10 AM EST THIS MORNING FOR
PAZ101>106.
NJ...FREEZING RAIN ADVISORY FROM 7 AM THIS MORNING TO NOON EST
TODAY FOR NJZ001-007-008.
FREEZING RAIN ADVISORY FROM 7 AM TO 10 AM EST THIS MORNING FOR
NJZ009-010-015.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT EST
TONIGHT FOR ANZ450>455.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...GORSE
AVIATION...GORSE/NIERENBERG
MARINE...GORSE/NIERENBERG
HYDROLOGY...MIKETTA/KRUZDLO
CLIMATE...
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
945 PM EST Thu Feb 20 2014
.Near Term [through Tonight]...
As of 02z, a broken squall line was taking shape to the west and
northwest of our local forecast area - roughly from Nashville, to
Tupelo, to Jackson MS, to Lake Charles LA. The convective line was
showing relatively consistent forward motion, and extrapolation of
the trends would have it arrive in the NW corner of our forecast
area around 10z. Extrapolation would also take the main line to
PAM-ABY around 13z, and TLH-VLD around 14-15z. This is very
similar to the most recent local WRF and HRRR runs. Thus, we
expect the primary convective line to spread into the forecast
area during the early-mid morning hours. As a result, PoPs were
decreased prior to 09z over all but the far western part of the
forecast area, with the bulk of the rain and storms moving in
after that time. Some fog was added to the grids over the entire
area overnight - mostly "patchy fog" wording in advance of the
more concentrated areas of thunderstorm activity. More widespread
fog with some lower visibilities will be possible south of I-10
and to the west of Tallahassee. Right now, we don`t anticipate
enough dense fog to warrant an advisory over land areas.
Regarding thunderstorm intensity - not much has changed from the
previous shift`s assessment: (1) storms should gradually weaken
through the morning as they move across the area from west to
east, (2) there will be the potential for some isolated damaging
wind gusts in stronger segments of convective lines, -AND- (3) the
greatest risk for severe weather will be over the western third
of our forecast area particularly west of a Panama City to Albany
line. Wind fields through the depth of the troposphere should be
decreasing (based on model consensus) from around the arrival time
of the storms (10z) through the rest of the morning hours.
Additionally, the strongest mid-upper level winds will already be
situated to the north of our forecast area. These factors should
contribute to the gradual weakening trend, as well as the more
limited instability further east. The bottom line is that isolated
severe weather is possible, but we are anticipating impacts to be
fairly localized.
&&
.Aviation...
[Through 00Z Saturday] IFR cigs have already returned to ECP and
are expected to eventually develop inland to the remainder of the
TAF sites overnight ahead of an approaching cold front. Storms are
expected to precede the front with stronger storms possible at DHN
and ABY. Gusts to 30kt or higher will be possible in stronger
storms. Clouds will scatter and winds will shift to the north
after frontal passage. High pressure will build quickly eastward
behind the front. Therefore, we are not expecting winds to be
gusts behind the front.
&&
.Marine...
We added a Marine Dense Fog Advisory for the nearshore leg of the
coastal waters from Destin to Apalachicola through 12z. The latest
model guidance indicates high probabilities of visibility below 1
mile, and a couple of recent surface observations near the FL
panhandle coastline confirm this.
Afternoon discussion: Moderate onshore flow this evening will
shift to the north late tonight through midday Friday as a cold
front crosses the waters from west to east. Winds may briefly
increase to near 20 knots immediately following the frontal
passage before diminishing by early Friday afternoon. Winds and
seas will then remain below headline criteria through the weekend.
&&
.Prev Discussion [325 PM EST]...
.Short Term [Friday afternoon Through Saturday Night]...
A cooler airmass will push quickly into the region in the wake of
the passing cold front, with temperatures dropping 10-15 degrees
in most areas. Afternoon sun should allow temperatures to recover
a bit, with afternoon high generally maxing out in the lower to
mid 60s. After a cool start to Saturday (lows ranging from the mid
30s over the west to the lower 50s in the eastern Big Bend), the
airmass will begin to modify, with afternoon highs returning to
the 70s.
The lingering remnants of the cold front are forecast to stall
over the eastern Big Bend Friday night, so a few showers will be
possible during the day on Saturday into Saturday evening for this
area. Additional showers may begin to move into the Florida
Panhandle by late Saturday night, as the next upper impulse
approaches the region.
.Long Term [Sunday Through Thursday]...
A stationary boundary will linger over north Florida bringing
plenty of cloud cover and a chance for rain until mid next week.
The best chance for rain and isolated thunder will be on Sunday as
a minor short wave trough moves through while there is ample gulf
moisture. A cold front will move through on Wednesday bringing
drier air and seasonable temps.
.Fire Weather...
Relative humidity values will remain above critical thresholds
through Wednesday next week.
.Hydrology...
Minor flooding continues along the Apalachicola River near
Blountstown. The river will remain in minor flood stage until
Friday afternoon. No significant impacts are expected. Measurable
rain is expected Fri/Sat/Sun but should remain around half an inch
with only isolated higher amounts. Rain showers are likely early
next week but should not be enough to affect river levels.
For the latest hydrology information, please monitor:
www.water.weather.gov/ahps2/index.php?wfo=tae
&&
.Preliminary Point Temps/PoPs...
Tallahassee 61 67 44 71 50 / 40 80 10 10 20
Panama City 61 65 48 68 56 / 70 80 10 10 30
Dothan 57 63 41 71 50 / 90 80 10 0 20
Albany 59 65 40 70 47 / 60 80 10 10 20
Valdosta 61 69 46 69 50 / 20 80 10 10 20
Cross City 60 76 51 72 53 / 20 60 20 30 20
Apalachicola 62 68 50 64 55 / 40 80 10 10 20
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...Dense Fog Advisory until 7 AM EST Friday for Coastal waters from
Apalachicola to Destin FL out 60 NM.
Small Craft Advisory from 5 AM to 1 PM EST Friday for Coastal
waters from Apalachicola to Destin FL out 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...CAMP
LONG TERM...MCDERMOTT
AVIATION...WOOL
MARINE...LAMERS
FIRE WEATHER...MOORE
HYDROLOGY...MCDERMOTT
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
749 PM EST THU FEB 20 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA EARLY FRIDAY BRINGING A CHANCE OF
SHOWERS AND THUNDERSTORMS. HIGH PRESSURE AND DRIER AIR WILL BUILD
INTO THE REGION FRIDAY EVENING.
&&
.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
FORECAST FOR THE OVERNIGHT CONTINUES TO LOOK ON TRACK. COLD FRONT
AND ASSOCIATED BAND OF SHOWERS AND THUNDERSTORMS EXPECTED TO
APPROACH THE CSRA AROUND DAYBREAK. AHEAD OF THE APPROACHING
FRONT...EXPECT INCREASING CLOUDINESS. CLOUDS AND A SOUTH WIND
STAYING UP WILL LEAD TO WARM MIN TEMPS TONIGHT.
&&
.SHORT TERM /7 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
COLD FRONT EXPECTED TO RAPIDLY MOVE THROUGH THE CWA FROM THE
MORNING INTO THE EARLY AFTERNOON. BY THE AFTERNOON THE FRONT WILL
BE MOVE MOVING EAST TO THE COAST AND OFFSHORE FRIDAY NIGHT. THERE
REMAINS A POTENTIAL FOR THUNDERSTORMS AHEAD OF THE FRONT...MAINLY
DUE TO THE LOW-LEVEL WINDS AROUND 850MB AT 50 TO 55 KNOTS. OTHER
CONCERN IS FOR DRIER AIR QUICKLY OVERTAKING THE MID LEVELS BEHIND
THE FRONT. ONE NEGATIVE IN REGARDS TO STORMS IS THAT THE MODELS
ARE SHOWING MUCH OF THE STRONGER UPPER ENERGY LIFTING NORTH OF THE
AREA DURING THE MORNING. OVERALL CONCERN FOR SEVERE POTENTIAL WITH
FROPA IS STILL POSSIBLE AT THIS TIME BUT WILL CONTINUE TO MONITOR.
HIGH TEMPERATURES WILL BE IN THE MID 60S FOR FRIDAY WITH TEMPERATURES
ONLY SLOWLY CLIMBING THROUGH THE MORNING AND THEN FALLING DURING THE
AFTERNOON. OVERNIGHT LOWS IN THE UPPER 30S TO THE LOWER 40S FRIDAY
NIGHT.
HIGH PRESSURE WILL BUILD IN OVER THE AREA FOR SATURDAY. COOLER WITH
HIGHS IN THE MIDDLE TO 60S. OVERNIGHT LOWS MAINLY IN THE LOWER TO
MIDDLE 40S SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
VERY FEW CHANGES IN THE EXTENDED FORECAST. NEAR ZONAL FLOW ALOFT
WITH WEAK IMPULSES WILL BE THE RULE SUNDAY THROUGH WEDNESDAY...WITH
A BROAD UPPER TROUGH DEVELOPING OVER THE SOUTHERN PLAINS BY
THURSDAY. OVERALL...WITH THE WEAK IMPULSES IN THE ZONAL
FLOW...EXPECT A SLIGHT CHANCE OF RAIN FOR PORTIONS OF THE LONG TERM
WITH SOME LOW CONFIDENCE WITH THE TIMING ISSUES. TEMPERATURES
THROUGH THE LONG TERM WILL BE NEAR TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
CURRENTLY VFR CONDITIONS AT ALL TAF SITES WITH MOSTLY CLEAR
SKIES...HOWEVER MAIN ISSUE THROUGH THE OVERNIGHT/EARLY MORNING
PERIOD WILL BE THE POTENTIAL FOR IFR CONDITIONS MAINLY FOR STRATUS
DEVELOPMENT. THE HRRR MODEL...AND THE SREF MODEL...INDICATING
FOG/STRATUS SPREADING INTO THE EASTERN MIDLAND FROM THE COAST LATE
THIS EVENING/JUST AFTER MIDNIGHT. THUS HAVE INDICATED IFR CIGS
DEVELOPING AT OGB/CUB/CAE DURING THE 06Z-07Z TIME-FRAME. MVFR OR
LOWER LOWER CONDITIONS TO DEVELOP AT AGS/DNL AFTER 06Z AS LOW LEVEL
MOISTURE INCREASES AHEAD OF AN APPROACHING COLD FRONT.
GUIDANCE SUGGESTS VSBYS WILL ALSO GO DOWN INTO THE IFR RANGE BUT
NOT AS CONFIDENT GIVEN MODERATE SURFACE WINDS AS THE PRESSURE
GRADIENT INCREASES AHEAD OF THE FRONT. WITH TIME SECTIONS INDICATING
A 40KT PLUS JET APPROACHING THE AREA AROUND 06Z AND CONTINUING
THROUGH THE MORNING...THINKING WOULD BE A MUCH GREATER CHANCE OF LOW
STRATUS THAN LOW VSBYS. COULD SEE ISOLATED SHOWERS AROUND THE
TERMINALS 08Z-11Z... WITH WIDESPREAD SHOWER AND THUNDERSTORMS
CROSSING THE TAF SITES IN THE 12-16Z TIME-FRAME AHEAD OF A STRONG
COLD FRONT. CONDITIONS SHOULD BEGIN TO IMPROVE AROUND 20Z/21Z AS
DRIER AIR BEGINS TO FILTER IN BEHIND THE FRONT ALONG WITH GUSTY
WINDS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SUNDAY NIGHT AND
AGAIN TUESDAY AS A COUPLE FRONTAL BOUNDARIES CROSS THE AREA.
&&
.CLIMATE...
DAILY RECORD HIGH BROKEN AT COLUMBIA TODAY. THE HIGH TODAY AT
COLUMBIA WAS 84...THE OLD DAILY RECORD HIGH FOR FEB 20TH WAS 83.
84 ALSO TIED THE ALL TIME RECORD HIGH FOR THE MONTH OF FEBRUARY AT
COLUMBIA...WHICH HAS OCCURRED MULTIPLE TIMES.
DAILY RECORD HIGH TIED AT AUGUSTA TODAY. THE HIGH TODAY AT
AUGUSTA WAS 82...WHICH TIED THE DAILY RECORD HIGH FOR FEB 20TH OF
82.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
655 PM EST THU FEB 20 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA EARLY FRIDAY BRINGING A CHANCE OF
SHOWERS AND THUNDERSTORMS. HIGH PRESSURE AND DRIER AIR WILL BUILD
INTO THE REGION FRIDAY EVENING.
&&
.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
LOW PRESSURE OVER THE CENTRAL PLAINS WILL LIFT NORTH TO THE
WESTERN GREAT LAKES TONIGHT. ITS ASSOCIATED COLD FRONT WILL CROSS
THE MS RIVER VALLEY THIS EVENING AND CROSS THE APPALACHIANS TOWARD
DAWN FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
INCREASE LATE TONIGHT AS THIS STRONG COLD FRONT APPROACHES. THE
HRRR MODEL INDICATING FOG/STRATUS SPREADING INTO THE EASTERN
MIDLANDS FROM THE COAST LATE THIS EVENING. IF THIS OCCURS A DENSE
FOG ADVISORY MAY BE NEEDED. LOW TEMPERATURES TONIGHT WILL BE
AROUND 60.
&&
.SHORT TERM /7 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
A STRONG COLD FRONT WILL BE JUST WEST OF THE FORECAST AREA BY
FRIDAY MORNING...AND IS EXPECTED TO RAPIDLY MOVE THROUGH THE CWA
FROM THE MORNING INTO THE EARLY AFTERNOON. BY THE AFTERNOON THE
FRONT WILL BE MOVE MOVING EAST TO THE COAST AND OFFSHORE FRIDAY
NIGHT. THERE REMAINS A POTENTIAL FOR THUNDERSTORMS AHEAD OF THE
FRONT...MAINLY DUE TO THE LOW-LEVEL WINDS AROUND 850MB AT 50 TO 55
KNOTS. OTHER CONCERN IS FOR DRIER AIR QUICKLY OVERTAKING THE MID
LEVELS BEHIND THE FRONT. ONE NEGATIVE IN REGARDS TO STORMS IS THAT
THE MODELS ARE SHOWING MUCH OF THE STRONGER UPPER ENERGY LIFTING
NORTH OF THE AREA DURING THE MORNING. OVERALL CONCERN FOR SEVERE
POTENTIAL WITH FROPA IS STILL POSSIBLE AT THIS TIME BUT WILL
CONTINUE TO MONITOR.
HIGH TEMPERATURES WILL BE IN THE MID 60S FOR FRIDAY WITH TEMPERATURES
ONLY SLOWLY CLIMBING THROUGH THE MORNING AND THEN FALLING DURING THE
AFTERNOON. OVERNIGHT LOWS IN THE UPPER 30S TO THE LOWER 40S FRIDAY
NIGHT.
HIGH PRESSURE WILL BUILD IN OVER THE AREA FOR SATURDAY. COOLER WITH
HIGHS IN THE MIDDLE TO 60S. OVERNIGHT LOWS MAINLY IN THE LOWER TO
MIDDLE 40S SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
VERY FEW CHANGES IN THE EXTENDED FORECAST. NEAR ZONAL FLOW ALOFT
WITH WEAK IMPULSES WILL BE THE RULE SUNDAY THROUGH WEDNESDAY...WITH
A BROAD UPPER TROUGH DEVELOPING OVER THE SOUTHERN PLAINS BY
THURSDAY. OVERALL...WITH THE WEAK IMPULSES IN THE ZONAL
FLOW...EXPECT A SLIGHT CHANCE OF RAIN FOR PORTIONS OF THE LONG TERM
WITH SOME LOW CONFIDENCE WITH THE TIMING ISSUES. TEMPERATURES
THROUGH THE LONG TERM WILL BE NEAR TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
CURRENTLY VFR CONDITIONS AT ALL TAF SITES WITH MOSTLY CLEAR
SKIES...HOWEVER MAIN ISSUE THROUGH THE OVERNIGHT/EARLY MORNING
PERIOD WILL BE THE POTENTIAL FOR IFR CONDITIONS MAINLY FOR STRATUS
DEVELOPMENT. THE HRRR MODEL...AND THE SREF MODEL...INDICATING
FOG/STRATUS SPREADING INTO THE EASTERN MIDLAND FROM THE COAST LATE
THIS EVENING/JUST AFTER MIDNIGHT. THUS HAVE INDICATED IFR CIGS
DEVELOPING AT OGB/CUB/CAE DURING THE 06Z-07Z TIME-FRAME. MVFR OR
LOWER LOWER CONDITIONS TO DEVELOP AT AGS/DNL AFTER 06Z AS LOW LEVEL
MOISTURE INCREASES AHEAD OF AN APPROACHING COLD FRONT.
GUIDANCE SUGGESTS VSBYS WILL ALSO GO DOWN INTO THE IFR RANGE BUT
NOT AS CONFIDENT GIVEN MODERATE SURFACE WINDS AS THE PRESSURE
GRADIENT INCREASES AHEAD OF THE FRONT. WITH TIME SECTIONS INDICATING
A 40KT PLUS JET APPROACHING THE AREA AROUND 06Z AND CONTINUING
THROUGH THE MORNING...THINKING WOULD BE A MUCH GREATER CHANCE OF LOW
STRATUS THAN LOW VSBYS. COULD SEE ISOLATED SHOWERS AROUND THE
TERMINALS 08Z-11Z... WITH WIDESPREAD SHOWER AND THUNDERSTORMS
CROSSING THE TAF SITES IN THE 12-16Z TIME-FRAME AHEAD OF A STRONG
COLD FRONT. CONDITIONS SHOULD BEGIN TO IMPROVE AROUND 20Z/21Z AS
DRIER AIR BEGINS TO FILTER IN BEHIND THE FRONT ALONG WITH GUSTY
WINDS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SUNDAY NIGHT AND
AGAIN TUESDAY AS A COUPLE FRONTAL BOUNDARIES CROSS THE AREA.
&&
.CLIMATE...
DAILY RECORD HIGH BROKEN AT COLUMBIA TODAY. THE HIGH TODAY AT
COLUMBIA WAS 84...THE OLD DAILY RECORD HIGH FOR FEB 20TH WAS 83.
84 ALSO TIED THE ALL TIME RECORD HIGH FOR THE MONTH OF FEBRUARY AT
COLUMBIA...WHICH HAS OCCURRED MULTIPLE TIMES.
DAILY RECORD HIGH TIED AT AUGUSTA TODAY. THE HIGH TODAY AT
AUGUSTA WAS 82...WHICH TIED THE DAILY RECORD HIGH FOR FEB 20TH OF
82.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
648 PM EST THU FEB 20 2014
.SYNOPSIS...
WARM TEMPERATURES CONTINUE ONCE AGAIN TODAY AHEAD OF AN
APPROACHING COLD FRONT. THIS STRONG COLD FRONT WILL CROSS THE
AREA FRIDAY BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE AND DRIER AIR WILL BUILD INTO THE REGION FRIDAY EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE WESTERN ATLANTIC.
WE ARE EXPECTING NEAR RECORD HIGH TEMPERATURES UNDER SUNNY SKIES
THIS AFTERNOON. TEMPERATURES SHOULD PEAK IN THE MID 70S TO LOWER
80S.
LOW PRESSURE OVER THE CENTRAL PLAINS WILL LIFT NORTH TO THE
WESTERN GREAT LAKES TONIGHT. ITS ASSOCIATED COLD FRONT WILL CROSS
THE MS RIVER VALLEY THIS EVENING AND CROSS THE APPALACHIANS TOWARD
DAWN FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
INCREASE LATE TONIGHT AS THIS STRONG COLD FRONT APPROACHES.
THE HRRR MODEL INDICATING FOG/STRATUS SPREADING INTO THE EASTERN
MIDLANDS FROM THE COAST LATE THIS EVENING. IF THIS OCCURS A DENSE
FOG ADVISORY MAY BE NEEDED. LOW TEMPERATURES TONIGHT WILL BE
AROUND 60.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
A STRONG COLD FRONT WILL BE JUST WEST OF THE FORECAST AREA BY
FRIDAY MORNING...AND IS EXPECTED TO RAPIDLY MOVE THROUGH THE CWA
FROM THE MORNING INTO THE EARLY AFTERNOON. BY THE AFTERNOON THE
FRONT WILL BE MOVE MOVING EAST TO THE COAST AND OFFSHORE FRIDAY
NIGHT. THERE REMAINS A POTENTIAL FOR THUNDERSTORMS AHEAD OF THE
FRONT...MAINLY DUE TO THE LOW-LEVEL WINDS AROUND 850MB AT 50 TO 55
KNOTS. OTHER CONCERN IS FOR DRIER AIR QUICKLY OVERTAKING THE MID
LEVELS BEHIND THE FRONT. ONE NEGATIVE IN REGARDS TO STORMS IS THAT
THE MODELS ARE SHOWING MUCH OF THE STRONGER UPPER ENERGY LIFTING
NORTH OF THE AREA DURING THE MORNING. OVERALL CONCERN FOR SEVERE
POTENTIAL WITH FROPA IS STILL POSSIBLE AT THIS TIME BUT WILL
CONTINUE TO MONITOR.
HIGH TEMPERATURES WILL BE IN THE MID 60S FOR FRIDAY WITH TEMPERATURES
ONLY SLOWLY CLIMBING THROUGH THE MORNING AND THEN FALLING DURING THE
AFTERNOON. OVERNIGHT LOWS IN THE UPPER 30S TO THE LOWER 40S FRIDAY
NIGHT.
HIGH PRESSURE WILL BUILD IN OVER THE AREA FOR SATURDAY. COOLER WITH
HIGHS IN THE MIDDLE TO 60S. OVERNIGHT LOWS MAINLY IN THE LOWER TO
MIDDLE 40S SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
VERY FEW CHANGES IN THE EXTENDED FORECAST. NEAR ZONAL FLOW ALOFT
WITH WEAK IMPULSES WILL BE THE RULE SUNDAY THROUGH WEDNESDAY...WITH
A BROAD UPPER TROUGH DEVELOPING OVER THE SOUTHERN PLAINS BY
THURSDAY. OVERALL...WITH THE WEAK IMPULSES IN THE ZONAL
FLOW...EXPECT A SLIGHT CHANCE OF RAIN FOR PORTIONS OF THE LONG TERM
WITH SOME LOW CONFIDENCE WITH THE TIMING ISSUES. TEMPERATURES
THROUGH THE LONG TERM WILL BE NEAR TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /00Z FRIDAY THROUGH WEDNESDAY/...
CURRENTLY VFR CONDITIONS AT ALL TAF SITES WITH MOSTLY CLEAR
SKIES...HOWEVER MAIN ISSUE THROUGH THE OVERNIGHT/EARLY MORNING
PERIOD WILL BE THE POTENTIAL FOR IFR CONDITIONS MAINLY FOR STRATUS
DEVELOPMENT. THE HRRR MODEL...AND THE SREF MODEL...INDICATING
FOG/STRATUS SPREADING INTO THE EASTERN MIDLAND FROM THE COAST LATE
THIS EVENING/JUST AFTER MIDNIGHT. THUS HAVE INDICATED IFR CIGS
DEVELOPING AT OGB/CUB/CAE DURING THE 06Z-07Z TIME-FRAME. MVFR OR
LOWER LOWER CONDITIONS TO DEVELOP AT AGS/DNL AFTER 06Z AS LOW LEVEL
MOISTURE INCREASES AHEAD OF AN APPROACHING COLD FRONT.
GUIDANCE SUGGESTS VSBYS WILL ALSO GO DOWN INTO THE IFR RANGE BUT
NOT AS CONFIDENT GIVEN MODERATE SURFACE WINDS AS THE PRESSURE
GRADIENT INCREASES AHEAD OF THE FRONT. WITH TIME SECTIONS INDICATING
A 40KT PLUS JET APPROACHING THE AREA AROUND 06Z AND CONTINUING
THROUGH THE MORNING...THINKING WOULD BE A MUCH GREATER CHANCE OF LOW
STRATUS THAN LOW VSBYS. COULD SEE ISOLATED SHOWERS AROUND THE
TERMINALS 08Z-11Z... WITH WIDESPREAD SHOWER AND THUNDERSTORMS
CROSSING THE TAF SITES IN THE 12-16Z TIME-FRAME AHEAD OF A STRONG
COLD FRONT. CONDITIONS SHOULD BEGIN TO IMPROVE AROUND 20Z/21Z AS
DRIER AIR BEGINS TO FILTER IN BEHIND THE FRONT ALONG WITH GUSTY
WINDS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SUNDAY NIGHT AND
AGAIN TUESDAY AS A COUPLE FRONTAL BOUNDARIES CROSS THE AREA.
&&
.CLIMATE...
HIGH TEMPERATURES THIS AFTERNOON APPROACHING DAILY RECORD VALUES.
AT CAE...RECORD HIGH FOR FEB 20TH IS 83 SET IN 1991.
AT AGS...RECORD HIGH FOR FEB 20TH IS 82 SET IN 1991.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
441 AM EST WED FEB 19 2014
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL REMAIN STALLED OVER THE AREA THROUGH
FRIDAY. ON FRIDAY A STRONG COLD FRONT WITH CHANCES OF SHOWERS AND
THUNDERSTORMS WILL CROSS THE AREA WITH HIGH PRESSURE AND DRIER AIR
BUILDING INTO THE REGION FRIDAY EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
WARM FRONT HAS CROSSED THE FORECAST AREA WITH SHOWERS AND
THUNDERSTORMS MOVING NORTHEASTWARD AWAY FROM THE AREA. HIGH
PRESSURE WILL BUILD BACK INTO THE REGION THIS AFTERNOON PUSHING
THE FRONTAL BOUNDARY BACK SOUTHWARD. DRIER AIR WILL MIX WITH THE
FRONTAL BOUNDARY AS IT MOVES SOUTHWARD RESULTING IN DIMINISHING
CLOUDS WITH NO RAIN EXPECTED. WINDS THROUGH THIS AFTERNOON WILL
BE AROUND 15 MPH WITH GUSTS TO 25 MPH THEN DIMINISH THIS EVENING
AS THE PRESSURE GRADIENT WEAKENS WITH HIGH PRESSURE BUILDING IN.
OVERNIGHT CLOUDS WILL BEGIN TO INCREASE AS SOUTHERLY FLOW
OVERTAKES THE REGION AND THE BOUNDARY SLIDES SLIGHTLY NORTHWARD.
TEMPERATURES THIS AFTERNOON WILL TOP OUT IN THE MIDDLE 70S FOR
MOST LOCATIONS WITH OVERNIGHT LOWS TONIGHT IN THE LOWER 50S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
LOW PRESSURE WILL DEEPEN AS IT CROSSES THE MID MS VALLEY THURSDAY
AFTERNOON THEN TRACKS INTO THE WESTERN GREAT LAKES THURSDAY NIGHT.
THIS WILL PUSH AN ASSOCIATED COLD FRONT ACROSS THE GULF STATES
THURSDAY NIGHT AND INTO THE FORECAST AREA FRIDAY MORNING. BY
FRIDAY AFTERNOON THE FRONT WILL MOVE TO THE COAST AND OFFSHORE
FRIDAY NIGHT. POTENTIAL FOR THUNDERSTORMS CONTINUES TO SLOWLY
INCREASE FOR COLD FRONT PASSAGE WITH CURRENT CONCERN SURROUNDING
SHEAR WITH WINDS AROUND 850MB NEARING 50 KNOTS. OTHER CONCERN IS
FOR DRIER AIR QUICKLY OVERTAKING THE MID LEVELS BEHIND THE FRONT.
OVERALL CONCERN FOR SEVERE POTENTIAL WITH FROPA REMAINS LOW AND
WILL CONTINUE TO MONITOR. HIGH TEMPERATURES WILL BE IN THE MID 70S
TO AROUND 80 THURSDAY WITH MID 60S TO AROUND 70 FOR THURSDAY AND
OVERNIGHT LOWS THURSDAY NIGHT AROUND 60 FALLING TO THE UPPER 30S
TO MID 40S FOR FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
MODELS THROUGH THE LONG TERM ARE IN GOOD AGREEMENT WITH THE
SYNOPTIC PATTERN...HOWEVER HAVE SIGNIFICANT DIFFERENCES IN TIMING
OF MOISTURE ACROSS THE REGION. HIGH PRESSURE AND DRIER AIR WILL
DOMINATE THE REGION FOR SATURDAY AND SUNDAY WITH THE REMAINS OF
FRONTAL BOUNDARY SOUTH OF THE AREA SLIDING NORTHWARD SUNDAY NIGHT
AND MONDAY. ECMWF BUILDS HIGH PRESSURE INTO THE FORECAST AREA
MONDAY EVENING WHILE THE GFS BRINGS THE FRONTAL BOUNDARY FURTHER
NORTHWARD. THE UNCERTAINTY CONTINUES THROUGH THE REMAINDER OF THE
LONG TERM RESULTING IN LOW CONFIDENCE AND ONLY MINOR ADJUSTMENTS
TO MONDAY THROUGH TUESDAY. TEMPERATURES THROUGH THE LONG TERM WILL
BE NEAR TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
MAINLY MID AND HIGH LEVEL CLOUDS MOVING ACROSS THE AREA. LOWER
CLOUDS ACROSS NORTH GEORGIA INTO SOUTH CAROLINA PIEDMONT. WARM FRONT
HAS MOVED NORTH OF THE REGION. THREAT OF SHOWERS APPEARS LOW. LOW
LEVEL SOUTHWEST WINDS WILL BE INCREASING DURING THE
MORNING...REDUCING FOG THREAT. LATEST HRRR AND LAMP SUGGEST IFR
CEILINGS MORE LIKELY WILL REMAIN WEST OF THE TERMINALS. BRIEF
PERIOD OF MVFR FORECAST THIS MORNING BUT CONFIDENCE LOW. VFR ALL
AREAS BY 15Z WITH GUSTY SOUTHWEST WINDS ABOVE 20 KTS AT TIMES
THROUGH THE EARLY AFTERNOON. DIMINISHING WINDS LATE.
EXTENDED AVIATION OUTLOOK...VSBY/CEILING FOG RESTRICTIONS
POSSIBLE EARLY THURSDAY MORNING. RESTRICTIONS POSSIBLE THURSDAY
NIGHT AND FRIDAY AS A STRONG COLD FRONT MOVES THROUGH THE REGION.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1238 AM EST WED FEB 19 2014
.SYNOPSIS...
A WARM FRONT WILL MOVE NORTH THROUGH THE REGION LATE TONIGHT THEN
STALL AND MEANDER ACROSS THE REGION OVER THE NEXT COUPLE OF DAYS
UNTIL A STRONG COLD FRONT FINALLY EJECTS IT FROM THE REGION ON
FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATE...ONGOING FORECAST CONTINUES TO APPEARS ON TRACK. EXPECT
INCREASING CLOUDINESS...WITH A CHANCE OF SHOWERS AND POSSIBLY A
THUNDERSTORM LATE TONIGHT. LATEST RADAR MOSAIC AND LIGHTNING
DISPLAY INDICATES A BAND OF SCATTERED SHOWERS WITH AN ISOLATED
THUNDERSTORM STRETCHING FROM N GA SE TOWARDS THE CSRA. ACTIVITY
MOVING TO THE ENE.
UPPER TROUGH WILL MOVE INTO THE EASTERN CONUS TONIGHT. COLD FRONT
WILL MOVE EAST ACROSS THE MIDWEST AND OHIO VALLEY TONIGHT...LEADING
TO AN INCREASED SW LOW LEVEL FLOW DOWN TO THE GULF COAST. THIS
WILL CAUSE A WARM FRONT TO OUR SW TO SHIFT NE THROUGH OUR REGION
LATE TONIGHT. AN UPPER IMPULSE WILL RIDE THROUGH OUR REGION AS
WELL LATE TONIGHT. HIGH RESOLUTION MODELS INDICATE PRECIPITATION
DEVELOPING ALONG THE WARM FRONT AND MOVING NE INTO...OR DEVELOPING
OVER...MAINLY NORTHERN PORTIONS OF THE CSRA AROUND OR AFTER
MIDNIGHT...WITH PRECIPITATION COVERAGE AND INTENSITY INCREASING
AND SPREADING EAST ACROSS THE REMAINDER OF THE FA...MAINLY
NORTH...LATE TONIGHT...EXITING THE NE/E FA AROUND DAYBREAK. WEAK
SURFACE BASED INSTABILITIES AND BEST MOISTURE TRANSPORT APPEAR TO
REMAIN MAINLY TO OUR WEST...WITH MAINLY WEAK ELEVATED INSTABILITIES
OVER OUR FA. POTENTIAL EXISTS FOR ISOLATED TO WIDELY SCATTERED
THUNDER ACCOMPANYING THE SHOWER ACTIVITY...GENERALLY FAVORING THE
NORTHERN FA. MIN TEMPS TONIGHT COULD BE APPROACHED EARLY...WITH
POTENTIAL FOR STEADY OR POSSIBLY EVEN SOME RISING TEMPS LATE
TONIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
THE WARM FRONT WILL BE JUST NORTH OF THE MIDLANDS WEDNESDAY. KEPT
SLIGHT CHANCE POPS ACROSS THE NORTHERN MIDLANDS GIVEN THE
PROXIMITY TO THE FRONTAL BOUNDARY. OTHERWISE WE EXPECT PARTIAL
CLEARING FROM THE SOUTH AND MODERATE SOUTHWEST WINDS 10 TO 15 MPH.
OUR WARMING TREND WILL CONTINUE WITH HIGHS IN THE LOW TO MID 70S.
WEDNESDAY NIGHT THROUGH THURSDAY... AN UPPER LEVEL TROUGH WILL
DEVELOP OVER THE CENTRAL CONUS WEDNESDAY NIGHT INTO THURSDAY WITH
DOWNSTREAM RIDGING OVER THE EASTERN CONUS. AT THE SURFACE...THE
LINGERING WARM FRONT WILL LIFT NORTH ACROSS THE NORTHERN PART OF
THE FORECAST AREA WEDNESDAY NIGHT. A LOW WILL DEVELOP OVER THE
CENTRAL PLAINS BY WEDNESDAY NIGHT AND WILL RAPIDLY SHIFT NORTH-
NORTHEASTWARD AND DEEPEN ON THURSDAY WITH A TRAILING COLD FRONT.
SURFACE HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WEDNESDAY
NIGHT WILL BE PUSHED OFFSHORE ON THURSDAY AS THE LOW PROGRESSES.
EXPECT THE COLD FRONT TO APPROACH THE OHIO AND TENNESSEE VALLEYS
BY THURSDAY EVENING WITH POSSIBLE LINEAR CONVECTION ALONG THE
FRONT. TEMPERATURES WILL CONTINUE TO WARM FOR THURSDAY WITH
OVERNIGHT LOWS IN THE UPPER 40S TO LOWER 50S WEDNESDAY NIGHT AND
LOWER TO UPPER 70S FOR AFTERNOON HIGHS.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...UPPER TROUGH WILL TRACK
TOWARD THE GREAT LAKES THURSDAY NIGHT AND DEEPEN WITH THE COLD
AT THE LEADING EDGE OF THE TROUGHING. WINDS WILL INCREASE LATE
THURSDAY INTO FRIDAY AS THE PRESSURE GRADIENT TIGHTENS. EXPECT THE
COLD FRONT TO EXTEND THROUGH THE LEE OF THE APPALACHIANS BY 12Z
FRIDAY MORNING. AS THE VIGOROUS FRONT CROSSES THE REGION...A LINE
OF CONVECTION MAY REDEVELOP. A HIGH SHEAR LOW CAPE SCENARIO IS
POSSIBLE ALTHOUGH INSTABILITY APPEARS LIMITED AT THIS TIME. AMOUNT
OF INSTABILITY WILL DEPEND ON THE TIMING OF THE FRONT AND AMOUNT
OF CLOUD COVER AND HEATING. DRY AIR MOVING IN BEHIND THE FRONT IS
ALSO A CONCERN. ECMWF IS A LITTLE SLOWER WITH THE TIMING OF THE
FRONT WHICH COULD RESULT IN MORE INSTABILITY. THE HIGHEST CHANCE OF
RAIN WILL BE WITH THE FRONTAL PASSAGE FRIDAY MORNING/EARLY
AFTERNOON. MODELS SHOW THE COLD FRONT EAST OF THE FORECAST AREA
FRIDAY EVENING.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
UNCERTAINTY REMAINS IN THE LONG TERM FORECAST WITH SIGNIFICANT
MODEL DIFFERENCES SUNDAY THROUGH MONDAY. AN UPPER RIDGE WILL BUILD
OVER THE WESTERN CONUS WITH BROAD TROUGHING OVER THE EASTERN
CONUS. THE FRONT WILL STALL ALONG THE COAST ON SATURDAY WITH
SURFACE HIGH PRESSURE AND DRIER AIR RIDGING IN BEHIND IT. WITH
CONFIDENCE LOW FOR SUNDAY AND MONDAY HAVE ONLY MADE MINOR
ADJUSTMENTS TO THE FORECAST BY BLENDING WITH LATEST WPC GUIDANCE.
EXPECT A GRADUAL COOLING TREND WITH TEMPERATURES. LATEST GUIDANCE
TRENDED DOWN WITH TEMPERATURES FOR MONDAY AND TUESDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
MID AND HIGH LEVEL CLOUDS MOVING ACROSS THE AREA. WARM FRONT
LIFTING NORTHEAST ACROSS THE REGION OVERNIGHT. BASED ON RADAR
TRENDS...RAIN THREAT APPEARS LOW AS FOCUS FOR CONVECTION SHIFTING
TO THE NORTH OF TERMINALS. HRRR AND LATEST NAM/RAP FORECAST
SOUNDINGS SUGGEST STRATUS OR STRATO-CU THREAT TOWARD MORNING WHICH
MAY RESULT IN IFR CEILINGS FOR A PERIOD FROM 10Z TO 13Z.
CONFIDENCE IS LOW HOWEVER AND NOT SUPPORTED BY LATEST LAMP. VFR
EXPECTED BY 15Z WITH GUSTY SOUTHWEST WINDS ABOVE 20 KTS AT TIMES
THROUGH THE EARLY AFTERNOON. DIMINISHING WINDS LATE.
EXTENDED AVIATION OUTLOOK...VSBY/CEILING FOG RESTRICTIONS
POSSIBLE EARLY THURSDAY MORNING. RESTRICTIONS POSSIBLE THURSDAY
NIGHT AND FRIDAY AS A STRONG COLD FRONT MOVES THROUGH THE REGION.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
413 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* NO CONCERNS IN THE NEAR TERM.
* WINTRY MIX OF PCPN BEGINNING DURG THE PRE-DAWN HOURS...LIKELY
SN/FZRA...THOUGH THERE IS A CHANCE THAT SOME IP COULD MIX IN
BRIEFLY. AMOUNT OF ICE ACCUMULATION IS UNCERTAIN.
* TIMING OF CHANGEOVER FROM WINTRY MIX TO ALL RAIN. LIKELY BY ARND
12Z...BUT EXACT TIMING IS STILL UNCERTAIN.
* VIS MAY DROP TO IFR...OR POSSIBLY LIFR...IN BR/FG BY LATE
MORNING OR EARLY AFTERNOON.
* CHANCE OF ISOLD/EMBEDDED TSRA LATE MORNING THROUGH EARLY
AFTERNOON UNTIL FRONTAL PASSAGE.
* WINDS SHIFTING TO SSWLY-SWLY BY EARLY AFTERNOON...STRENGTHENING
AND BECMG GUSTY TO ARND 30KT IN THE LATE AFTERNOON. GUSTS COULD
POSSIBLY BE EVEN HIGHER LATE AFTERNOON/EARLY EVENING.
KREIN/BMD
//DISCUSSION...UPDATED 18Z...UPDATED 1845Z...
QUIET CONDITIONS THROUGH LATE TONIGHT. CLEAR SKIES WILL GIVE WAY
TO INCREASING MID AND HIGH CLOUD AS A COMPLEX WEATHER SYSTEM
DEVELOPS OVER THE CENTRAL PLAINS AND CLOUD COVER BEGINS TO RACE
OUT AHEAD OF THE DOUBLE BARRELED LOW PRESSURE SYSTEM. OF MAIN
CONCERN TO NRN IL/NWRN INDIANA WILL BE THE TRACK AND DEVELOPMENT
OF THE SOUTHERN OF THE 2 LOWS...WHICH IS EXPECTED TO INITIALLY
DEVELOP OVER THE SOUTH HIGH PLAINS AND AND RAPIDLY DEEPEN AS IT
TRACKS THROUGH THE MIDDLE MISSISSIPPI VALLEY TO EASTERN WISCONSIN
BY EARLY TOMORROW EVENING.
THIS SYSTEM WILL BRING A COMPLEX WEATHER SCENARIO TO THE TERMINALS
WHICH WILL BE HIGHLY DEPENDANT ON THE EXACT TRACK OF THE
SYSTEM...AS WELL AS THE IMPACT OF THE DENSE SNOW PACK OVER THE
REGION. BASED ON THE CURRENTLY EXPECTED TRACK...AN ASSOCIATED WARM
FRONT WOULD LIFT NWD THROUGH THE REGION. WITH WARMER AIR ALOFT
OVERRIDING THE COLDER AIR AND SNOW PACK AT THE SFC...PCPN SHOULD
START OUT AS EITHER ALL SNOW...OR A WINTRY MIX OF
FZRA/IP/SN/RA...WHICH WILL BE HIGHLY DEPENDANT ON THE DEPTH AND
DURATION OF A SUB-FREEZING LAYER AT THE SFC...WITH THE DENSE
SNOWPACK POSSIBLY HELPING TO KEEP SFC TEMPS AT ARND THE FREEZING
MARK. THERE ARE PLEANTY OF QUESTIONS MARKS WITH THIS
SYSTEM...AMONG THEM BEING THE DURATION OF THE FREEZING AND FROZEN
PCPN TYPES. THE SYSTEM IS EXPECTED TO BE VERY FAST-MOVING...BUT
VERY DYNAMIC. THE SPEED OF THE SYSTEM WILL HELP LIMIT THE DURATION
OF THE FREEZING/FROZEN PCPN AND SNOW OR ICE ACCUMULATIONS WOULD BE
MINOR...BUT THE DYNAMICS OF THE SYSTEM COULD HELP GENERATE SOME
ADDITIONAL DYNAMIC COOLING...WHICH WOULD DELAY A CHAGEOVER FROM
SNOW TO FREEZING PCPN AND ADD TO THE SNOW ACCUMULATION TOTALS.
BEST ESTIMATION AT THIS POINT WOULD BE THAT ICE AND SNOW
ACCUMULATIONS WILL BE RELATIVELY MINOR...BUT ENOUGH TO HAVE A
SIGNIFICANT IMPACT ON OPERATIONS EVEN IF THE DURATION IS LIMITED
TO 2-3 HOURS. HAVE RELATIVELY HIGH CONFIDENCE THAT PCPN WILL
CHANGE OVER TO ALL RAIN AS THE WARM FRONT LIFTS NORTH OF THE
TERMINALS. HOWEVER...THIS WILL BRING THE NEXT SIGNIFICANT CONCERN
OF HEAVY RAIN WITH EMBEDDED THUNDERSTORMS. BASED ON THE CURRENTLY
ANTICIPATED TRACK OF THE SYSTEM...WITH THE MAIN SFC LOW PASSING
THROUGH FAR NWRN IL WOULD PUT THE TERMINAL AREAS INTO A WARM
SECTOR OF THE SYSTEM...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT. THE STRONGEST FORCING AND INSTABILITY SHOULD FOCUS THE MOST
EXTENSIVE AND STRONGEST THUNDERSTORMS TO THE SOUTHEAST OF THE
TERMINALS...BUT FORCING AND INSTABILITY SHOULD BE SUFFICIENT FOR
ISOLATED/EMBEDDED THUNDER FROM LATE MORNING AND THROUGH THE
AFTERNOON HOURS. IN ADDITION TO THE RAIN AND THUNDER
CONCERNS...ALSO HAVE CONCERN FOR THE POTENTIAL FOR DENSE FOG WITH
THE ADVECTION OF WARM/MOIST AIR OVER THE SNOW PACK...WHICH WILL
ALSO HAVE INCREASING MOISTURE CONTENT AS THE SNOW ABSORBS THE
FALLING RAIN. WITH HIGH DEWPOINT WARM AIR OVERSPREADING THE
SNOW...THERE IS A CONCERN THAT DENSE FOG COULD DEVELOP BY LATE
MORNING/EARLY AFTERNOON...EVEN WITH STRENGTHENING SELY-SLY WINDS.
HAVE LIMITED THE LOWER EXTENT OF THE VISBY TO 3/4SM TO 1SM FOR
TOMORROW...BUT THERE IS THE POTENTIAL FOR PERIODS OF VISBY
DROPPING TO 1/4SM IN FOG UNTIL THE PASSAGE OF THE STRONG COLD
FRONT TOMORROW EVENING.
THE THIRD CONCERN WILL THEN BECOME WINDS. SELY WINDS WILL BEGIN
TO INCREASE THROUGH THE MORNING WITH THE APPROACH OF THE COLD
FRONT...WITH SELY-SLY WINDS INCREASING AND BECMG GUSTY APPROACHING
30KT LATE THIS AFTERNOON. WHILE IT WILL BE AFTER THE CURRENT TAF
PERIOD...WINDS WILL SHIFT THROUGH SWLY TO WLY FOLLOWING THE FROPA
AND INCREASE FURTHER...POSSIBLY GUSTING TO 40KT EARLY TOMORROW
EVENING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS THROUGH LATE TONIGHT.
* HIGH CONFIDENCE IN A PERIOD OF A WINTRY MIX OF PCPN DURG THE
EARLY MORNING HOURS...BUT LOWER CONFIDENCE IN TIMING AND
DURATION OF THE WINTRY MIX PCPN.
* HIGH CONFIDENCE THAT PCPN WILL CHANGE OVER TO ALL RAIN BY LATE
MORNING...BUT LOWER CONFIDENCE IN EXACT TIMING.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN VISBY TRENDS...ESPECIALLY RELATED TO
THE CHANCE FOR IFR/LIFR VIS IN FOG DEVELOPING LATE TOMORROW
MORNING INTO TOMORROW AFTERNOON.
KREIN/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...RAIN OR SNOW SHOWERS...WITH POSSIBLE MVFR
CONDITIONS. VERY STRONG SOUTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS
UP TO 50 MPH
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF LIGHT SNOW.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NO CONCERNS IN THE NEAR TERM.
* WINTRY MIX OF PCPN BEGINNING DURG THE PRE-DAWN HOURS...LIKELY
SN/FZRA...THOUGH THERE IS A CHANCE THAT SOME IP COULD MIX IN
BRIEFLY. AMOUNT OF ICE ACCUMULATION IS UNCERTAIN.
* TIMING OF CHANGEOVER FROM WINTRY MIX TO ALL RAIN. LIKELY BY ARND
12Z...BUT EXACT TIMING IS STILL UNCERTAIN.
* VIS MAY DROP TO IFR...OR POSSIBLY LIFR...IN BR/FG BY LATE
MORNING OR EARLY AFTERNOON.
* CHANCE OF ISOLD/EMBEDDED TSRA LATE MORNING THROUGH EARLY
AFTERNOON UNTIL FRONTAL PASSAGE.
* WINDS SHIFTING TO SSWLY-SWLY BY EARLY AFTERNOON...STRENGTHENING
AND BECMG GUSTY TO ARND 30KT IN THE LATE AFTERNOON. GUSTS COULD
POSSIBLY BE EVEN HIGHER LATE AFTERNOON/EARLY EVENING.
KREIN
//DISCUSSION...UPDATED 18Z...UPDATED 1845Z...
QUIET CONDITIONS THROUGH LATE TONIGHT. CLEAR SKIES WILL GIVE WAY
TO INCREASING MID AND HIGH CLOUD AS A COMPLEX WEATHER SYSTEM
DEVELOPS OVER THE CENTRAL PLAINS AND CLOUD COVER BEGINS TO RACE
OUT AHEAD OF THE DOUBLE BARRELED LOW PRESSURE SYSTEM. OF MAIN
CONCERN TO NRN IL/NWRN INDIANA WILL BE THE TRACK AND DEVELOPMENT
OF THE SOUTHERN OF THE 2 LOWS...WHICH IS EXPECTED TO INITIALLY
DEVELOP OVER THE SOUTH HIGH PLAINS AND AND RAPIDLY DEEPEN AS IT
TRACKS THROUGH THE MIDDLE MISSISSIPPI VALLEY TO EASTERN WISCONSIN
BY EARLY TOMORROW EVENING.
THIS SYSTEM WILL BRING A COMPLEX WEATHER SCENARIO TO THE TERMINALS
WHICH WILL BE HIGHLY DEPENDANT ON THE EXACT TRACK OF THE
SYSTEM...AS WELL AS THE IMPACT OF THE DENSE SNOW PACK OVER THE
REGION. BASED ON THE CURRENTLY EXPECTED TRACK...AN ASSOCIATED WARM
FRONT WOULD LIFT NWD THROUGH THE REGION. WITH WARMER AIR ALOFT
OVERRIDING THE COLDER AIR AND SNOW PACK AT THE SFC...PCPN SHOULD
START OUT AS EITHER ALL SNOW...OR A WINTRY MIX OF
FZRA/IP/SN/RA...WHICH WILL BE HIGHLY DEPENDANT ON THE DEPTH AND
DURATION OF A SUB-FREEZING LAYER AT THE SFC...WITH THE DENSE
SNOWPACK POSSIBLY HELPING TO KEEP SFC TEMPS AT ARND THE FREEZING
MARK. THERE ARE PLEANTY OF QUESTIONS MARKS WITH THIS
SYSTEM...AMONG THEM BEING THE DURATION OF THE FREEZING AND FROZEN
PCPN TYPES. THE SYSTEM IS EXPECTED TO BE VERY FAST-MOVING...BUT
VERY DYNAMIC. THE SPEED OF THE SYSTEM WILL HELP LIMIT THE DURATION
OF THE FREEZING/FROZEN PCPN AND SNOW OR ICE ACCUMULATIONS WOULD BE
MINOR...BUT THE DYNAMICS OF THE SYSTEM COULD HELP GENERATE SOME
ADDITIONAL DYNAMIC COOLING...WHICH WOULD DELAY A CHAGEOVER FROM
SNOW TO FREEZING PCPN AND ADD TO THE SNOW ACCUMULATION TOTALS.
BEST ESTIMATION AT THIS POINT WOULD BE THAT ICE AND SNOW
ACCUMULATIONS WILL BE RELATIVELY MINOR...BUT ENOUGH TO HAVE A
SIGNIFICANT IMPACT ON OPERATIONS EVEN IF THE DURATION IS LIMITED
TO 2-3 HOURS. HAVE RELATIVELY HIGH CONFIDENCE THAT PCPN WILL
CHANGE OVER TO ALL RAIN AS THE WARM FRONT LIFTS NORTH OF THE
TERMINALS. HOWEVER...THIS WILL BRING THE NEXT SIGNIFICANT CONCERN
OF HEAVY RAIN WITH EMBEDDED THUNDERSTORMS. BASED ON THE CURRENTLY
ANTICIPATED TRACK OF THE SYSTEM...WITH THE MAIN SFC LOW PASSING
THROUGH FAR NWRN IL WOULD PUT THE TERMINAL AREAS INTO A WARM
SECTOR OF THE SYSTEM...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT. THE STRONGEST FORCING AND INSTABILITY SHOULD FOCUS THE MOST
EXTENSIVE AND STRONGEST THUNDERSTORMS TO THE SOUTHEAST OF THE
TERMINALS...BUT FORCING AND INSTABILITY SHOULD BE SUFFICIENT FOR
ISOLATED/EMBEDDED THUNDER FROM LATE MORNING AND THROUGH THE
AFTERNOON HOURS. IN ADDITION TO THE RAIN AND THUNDER
CONCERNS...ALSO HAVE CONCERN FOR THE POTENTIAL FOR DENSE FOG WITH
THE ADVECTION OF WARM/MOIST AIR OVER THE SNOW PACK...WHICH WILL
ALSO HAVE INCREASING MOISTURE CONTENT AS THE SNOW ABSORBS THE
FALLING RAIN. WITH HIGH DEWPOINT WARM AIR OVERSPREADING THE
SNOW...THERE IS A CONCERN THAT DENSE FOG COULD DEVELOP BY LATE
MORNING/EARLY AFTERNOON...EVEN WITH STRENGTHENING SELY-SLY WINDS.
HAVE LIMITED THE LOWER EXTENT OF THE VISBY TO 3/4SM TO 1SM FOR
TOMORROW...BUT THERE IS THE POTENTIAL FOR PERIODS OF VISBY
DROPPING TO 1/4SM IN FOG UNTIL THE PASSAGE OF THE STRONG COLD
FRONT TOMORROW EVENING.
THE THIRD CONCERN WILL THEN BECOME WINDS. SELY WINDS WILL BEGIN
TO INCREASE THROUGH THE MORNING WITH THE APPROACH OF THE COLD
FRONT...WITH SELY-SLY WINDS INCREASING AND BECMG GUSTY APPROACHING
30KT LATE THIS AFTERNOON. WHILE IT WILL BE AFTER THE CURRENT TAF
PERIOD...WINDS WILL SHIFT THROUGH SWLY TO WLY FOLLOWING THE FROPA
AND INCREASE FURTHER...POSSIBLY GUSTING TO 40KT EARLY TOMORROW
EVENING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS THROUGH LATE TONIGHT.
* HIGH CONFIDENCE IN A PERIOD OF A WINTRY MIX OF PCPN DURG THE
EARLY MORNING HOURS...BUT LOWER CONFIDENCE IN TIMING AND
DURATION OF THE WINTRY MIX PCPN.
* HIGH CONFIDENCE THAT PCPN WILL CHANGE OVER TO ALL RAIN BY LATE
MORNING...BUT LOWER CONFIDENCE IN EXACT TIMING.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN VISBY TRENDS...ESPECIALLY RELATED TO
THE CHANCE FOR IFR/LIFR VIS IN FOG DEVELOPING LATE TOMORROW
MORNING INTO TOMORROW AFTERNOON.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...RAIN OR SNOW SHOWERS...WITH POSSIBLE MVFR
CONDITIONS. VERY STRONG SOUTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS
UP TO 50 MPH
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF LIGHT SNOW.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
322 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NO CONCERNS IN THE NEAR TERM.
* WINTRY MIX OF PCPN BEGINNING DURG THE PRE-DAWN HOURS...LIKELY
SN/FZRA...THOUGH THERE IS A CHANCE THAT SOME IP COULD MIX IN
BRIEFLY. AMOUNT OF ICE ACCUMULATION IS UNCERTAIN.
* TIMING OF CHANGEOVER FROM WINTRY MIX TO ALL RAIN. LIKELY BY ARND
12Z...BUT EXACT TIMING IS STILL UNCERTAIN.
* VIS MAY DROP TO IFR...OR POSSIBLY LIFR...IN BR/FG BY LATE
MORNING OR EARLY AFTERNOON.
* CHANCE OF ISOLD/EMBEDDED TSRA LATE MORNING THROUGH EARLY
AFTERNOON UNTIL FRONTAL PASSAGE.
* WINDS SHIFTING TO SSWLY-SWLY BY EARLY AFTERNOON...STRENGTHENING
AND BECMG GUSTY TO ARND 30KT IN THE LATE AFTERNOON. GUSTS COULD
POSSIBLY BE EVEN HIGHER LATE AFTERNOON/EARLY EVENING.
KREIN
//DISCUSSION...UPDATED 18Z...UPDATED 1845Z...
QUIET CONDITIONS THROUGH LATE TONIGHT. CLEAR SKIES WILL GIVE WAY
TO INCREASING MID AND HIGH CLOUD AS A COMPLEX WEATHER SYSTEM
DEVELOPS OVER THE CENTRAL PLAINS AND CLOUD COVER BEGINS TO RACE
OUT AHEAD OF THE DOUBLE BARRELED LOW PRESSURE SYSTEM. OF MAIN
CONCERN TO NRN IL/NWRN INDIANA WILL BE THE TRACK AND DEVELOPMENT
OF THE SOUTHERN OF THE 2 LOWS...WHICH IS EXPECTED TO INITIALLY
DEVELOP OVER THE SOUTH HIGH PLAINS AND AND RAPIDLY DEEPEN AS IT
TRACKS THROUGH THE MIDDLE MISSISSIPPI VALLEY TO EASTERN WISCONSIN
BY EARLY TOMORROW EVENING.
THIS SYSTEM WILL BRING A COMPLEX WEATHER SCENARIO TO THE TERMINALS
WHICH WILL BE HIGHLY DEPENDANT ON THE EXACT TRACK OF THE
SYSTEM...AS WELL AS THE IMPACT OF THE DENSE SNOW PACK OVER THE
REGION. BASED ON THE CURRENTLY EXPECTED TRACK...AN ASSOCIATED WARM
FRONT WOULD LIFT NWD THROUGH THE REGION. WITH WARMER AIR ALOFT
OVERRIDING THE COLDER AIR AND SNOW PACK AT THE SFC...PCPN SHOULD
START OUT AS EITHER ALL SNOW...OR A WINTRY MIX OF
FZRA/IP/SN/RA...WHICH WILL BE HIGHLY DEPENDANT ON THE DEPTH AND
DURATION OF A SUB-FREEZING LAYER AT THE SFC...WITH THE DENSE
SNOWPACK POSSIBLY HELPING TO KEEP SFC TEMPS AT ARND THE FREEZING
MARK. THERE ARE PLEANTY OF QUESTIONS MARKS WITH THIS
SYSTEM...AMONG THEM BEING THE DURATION OF THE FREEZING AND FROZEN
PCPN TYPES. THE SYSTEM IS EXPECTED TO BE VERY FAST-MOVING...BUT
VERY DYNAMIC. THE SPEED OF THE SYSTEM WILL HELP LIMIT THE DURATION
OF THE FREEZING/FROZEN PCPN AND SNOW OR ICE ACCUMULATIONS WOULD BE
MINOR...BUT THE DYNAMICS OF THE SYSTEM COULD HELP GENERATE SOME
ADDITIONAL DYNAMIC COOLING...WHICH WOULD DELAY A CHAGEOVER FROM
SNOW TO FREEZING PCPN AND ADD TO THE SNOW ACCUMULATION TOTALS.
BEST ESTIMATION AT THIS POINT WOULD BE THAT ICE AND SNOW
ACCUMULATIONS WILL BE RELATIVELY MINOR...BUT ENOUGH TO HAVE A
SIGNIFICANT IMPACT ON OPERATIONS EVEN IF THE DURATION IS LIMITED
TO 2-3 HOURS. HAVE RELATIVELY HIGH CONFIDENCE THAT PCPN WILL
CHANGE OVER TO ALL RAIN AS THE WARM FRONT LIFTS NORTH OF THE
TERMINALS. HOWEVER...THIS WILL BRING THE NEXT SIGNIFICANT CONCERN
OF HEAVY RAIN WITH EMBEDDED THUNDERSTORMS. BASED ON THE CURRENTLY
ANTICIPATED TRACK OF THE SYSTEM...WITH THE MAIN SFC LOW PASSING
THROUGH FAR NWRN IL WOULD PUT THE TERMINAL AREAS INTO A WARM
SECTOR OF THE SYSTEM...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT. THE STRONGEST FORCING AND INSTABILITY SHOULD FOCUS THE MOST
EXTENSIVE AND STRONGEST THUNDERSTORMS TO THE SOUTHEAST OF THE
TERMINALS...BUT FORCING AND INSTABILITY SHOULD BE SUFFICIENT FOR
ISOLATED/EMBEDDED THUNDER FROM LATE MORNING AND THROUGH THE
AFTERNOON HOURS. IN ADDITION TO THE RAIN AND THUNDER
CONCERNS...ALSO HAVE CONCERN FOR THE POTENTIAL FOR DENSE FOG WITH
THE ADVECTION OF WARM/MOIST AIR OVER THE SNOW PACK...WHICH WILL
ALSO HAVE INCREASING MOISTURE CONTENT AS THE SNOW ABSORBS THE
FALLING RAIN. WITH HIGH DEWPOINT WARM AIR OVERSPREADING THE
SNOW...THERE IS A CONCERN THAT DENSE FOG COULD DEVELOP BY LATE
MORNING/EARLY AFTERNOON...EVEN WITH STRENGTHENING SELY-SLY WINDS.
HAVE LIMITED THE LOWER EXTENT OF THE VISBY TO 3/4SM TO 1SM FOR
TOMORROW...BUT THERE IS THE POTENTIAL FOR PERIODS OF VISBY
DROPPING TO 1/4SM IN FOG UNTIL THE PASSAGE OF THE STRONG COLD
FRONT TOMORROW EVENING.
THE THIRD CONCERN WILL THEN BECOME WINDS. SELY WINDS WILL BEGIN
TO INCREASE THROUGH THE MORNING WITH THE APPROACH OF THE COLD
FRONT...WITH SELY-SLY WINDS INCREASING AND BECMG GUSTY APPROACHING
30KT LATE THIS AFTERNOON. WHILE IT WILL BE AFTER THE CURRENT TAF
PERIOD...WINDS WILL SHIFT THROUGH SWLY TO WLY FOLLOWING THE FROPA
AND INCREASE FURTHER...POSSIBLY GUSTING TO 40KT EARLY TOMORROW
EVENING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS THROUGH LATE TONIGHT.
* HIGH CONFIDENCE IN A PERIOD OF A WINTRY MIX OF PCPN DURG THE
EARLY MORNING HOURS...BUT LOWER CONFIDENCE IN TIMING AND
DURATION OF THE WINTRY MIX PCPN.
* HIGH CONFIDENCE THAT PCPN WILL CHANGE OVER TO ALL RAIN BY LATE
MORNING...BUT LOWER CONFIDENCE IN EXACT TIMING.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN VISBY TRENDS...ESPECIALLY RELATED TO
THE CHANCE FOR IFR/LIFR VIS IN FOG DEVELOPING LATE TOMORROW
MORNING INTO TOMORROW AFTERNOON.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...RAIN OR SNOW SHOWERS...WITH POSSIBLE MVFR
CONDITIONS. VERY STRONG SOUTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS
UP TO 50 MPH
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF LIGHT SNOW.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
315 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NO CONCERNS IN THE NEAR TERM.
* WINTRY MIX OF PCPN BEGINNING DURG THE PRE-DAWN HOURS...LIKELY
SN/FZRA...THOUGH THERE IS A CHANCE THAT SOME IP COULD MIX IN
BRIEFLY. AMOUNT OF ICE ACCUMULATION IS UNCERTAIN.
* TIMING OF CHANGEOVER FROM WINTRY MIX TO ALL RAIN. LIKELY BY ARND
12Z...BUT EXACT TIMING IS STILL UNCERTAIN.
* VIS MAY DROP TO IFR...OR POSSIBLY LIFR...IN BR/FG BY LATE
MORNING OR EARLY AFTERNOON.
* CHANCE OF ISOLD/EMBEDDED TSRA LATE MORNING THROUGH EARLY
AFTERNOON UNTIL FRONTAL PASSAGE.
* WINDS SHIFTING TO SSWLY-SWLY BY EARLY AFTERNOON...STRENGTHENING
AND BECMG GUSTY TO ARND 30KT IN THE LATE AFTERNOON. GUSTS COULD
POSSIBLY BE EVEN HIGHER LATE AFTERNOON/EARLY EVENING.
KREIN
//DISCUSSION...UPDATED 18Z...UPDATED 1845Z...
QUIET CONDITIONS THROUGH LATE TONIGHT. CLEAR SKIES WILL GIVE WAY
TO INCREASING MID AND HIGH CLOUD AS A COMPLEX WEATHER SYSTEM
DEVELOPS OVER THE CENTRAL PLAINS AND CLOUD COVER BEGINS TO RACE
OUT AHEAD OF THE DOUBLE BARRELED LOW PRESSURE SYSTEM. OF MAIN
CONCERN TO NRN IL/NWRN INDIANA WILL BE THE TRACK AND DEVELOPMENT
OF THE SOUTHERN OF THE 2 LOWS...WHICH IS EXPECTED TO INITIALLY
DEVELOP OVER THE SOUTH HIGH PLAINS AND AND RAPIDLY DEEPEN AS IT
TRACKS THROUGH THE MIDDLE MISSISSIPPI VALLEY TO EASTERN WISCONSIN
BY EARLY TOMORROW EVENING.
THIS SYSTEM WILL BRING A COMPLEX WEATHER SCENARIO TO THE TERMINALS
WHICH WILL BE HIGHLY DEPENDANT ON THE EXACT TRACK OF THE
SYSTEM...AS WELL AS THE IMPACT OF THE DENSE SNOW PACK OVER THE
REGION. BASED ON THE CURRENTLY EXPECTED TRACK...AN ASSOCIATED WARM
FRONT WOULD LIFT NWD THROUGH THE REGION. WITH WARMER AIR ALOFT
OVERRIDING THE COLDER AIR AND SNOW PACK AT THE SFC...PCPN SHOULD
START OUT AS EITHER ALL SNOW...OR A WINTRY MIX OF
FZRA/IP/SN/RA...WHICH WILL BE HIGHLY DEPENDANT ON THE DEPTH AND
DURATION OF A SUB-FREEZING LAYER AT THE SFC...WITH THE DENSE
SNOWPACK POSSIBLY HELPING TO KEEP SFC TEMPS AT ARND THE FREEZING
MARK. THERE ARE PLEANTY OF QUESTIONS MARKS WITH THIS
SYSTEM...AMONG THEM BEING THE DURATION OF THE FREEZING AND FROZEN
PCPN TYPES. THE SYSTEM IS EXPECTED TO BE VERY FAST-MOVING...BUT
VERY DYNAMIC. THE SPEED OF THE SYSTEM WILL HELP LIMIT THE DURATION
OF THE FREEZING/FROZEN PCPN AND SNOW OR ICE ACCUMULATIONS WOULD BE
MINOR...BUT THE DYNAMICS OF THE SYSTEM COULD HELP GENERATE SOME
ADDITIONAL DYNAMIC COOLING...WHICH WOULD DELAY A CHAGEOVER FROM
SNOW TO FREEZING PCPN AND ADD TO THE SNOW ACCUMULATION TOTALS.
BEST ESTIMATION AT THIS POINT WOULD BE THAT ICE AND SNOW
ACCUMULATIONS WILL BE RELATIVELY MINOR...BUT ENOUGH TO HAVE A
SIGNIFICANT IMPACT ON OPERATIONS EVEN IF THE DURATION IS LIMITED
TO 2-3 HOURS. HAVE RELATIVELY HIGH CONFIDENCE THAT PCPN WILL
CHANGE OVER TO ALL RAIN AS THE WARM FRONT LIFTS NORTH OF THE
TERMINALS. HOWEVER...THIS WILL BRING THE NEXT SIGNIFICANT CONCERN
OF HEAVY RAIN WITH EMBEDDED THUNDERSTORMS. BASED ON THE CURRENTLY
ANTICIPATED TRACK OF THE SYSTEM...WITH THE MAIN SFC LOW PASSING
THROUGH FAR NWRN IL WOULD PUT THE TERMINAL AREAS INTO A WARM
SECTOR OF THE SYSTEM...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT. THE STRONGEST FORCING AND INSTABILITY SHOULD FOCUS THE MOST
EXTENSIVE AND STRONGEST THUNDERSTORMS TO THE SOUTHEAST OF THE
TERMINALS...BUT FORCING AND INSTABILITY SHOULD BE SUFFICIENT FOR
ISOLATED/EMBEDDED THUNDER FROM LATE MORNING AND THROUGH THE
AFTERNOON HOURS. IN ADDITION TO THE RAIN AND THUNDER
CONCERNS...ALSO HAVE CONCERN FOR THE POTENTIAL FOR DENSE FOG WITH
THE ADVECTION OF WARM/MOIST AIR OVER THE SNOW PACK...WHICH WILL
ALSO HAVE INCREASING MOISTURE CONTENT AS THE SNOW ABSORBS THE
FALLING RAIN. WITH HIGH DEWPOINT WARM AIR OVERSPREADING THE
SNOW...THERE IS A CONCERN THAT DENSE FOG COULD DEVELOP BY LATE
MORNING/EARLY AFTERNOON...EVEN WITH STRENGTHENING SELY-SLY WINDS.
HAVE LIMITED THE LOWER EXTENT OF THE VISBY TO 3/4SM TO 1SM FOR
TOMORROW...BUT THERE IS THE POTENTIAL FOR PERIODS OF VISBY
DROPPING TO 1/4SM IN FOG UNTIL THE PASSAGE OF THE STRONG COLD
FRONT TOMORROW EVENING.
THE THIRD CONCERN WILL THEN BECOME WINDS. SELY WINDS WILL BEGIN
TO INCREASE THROUGH THE MORNING WITH THE APPROACH OF THE COLD
FRONT...WITH SELY-SLY WINDS INCREASING AND BECMG GUSTY APPROACHING
30KT LATE THIS AFTERNOON. WHILE IT WILL BE AFTER THE CURRENT TAF
PERIOD...WINDS WILL SHIFT THROUGH SWLY TO WLY FOLLOWING THE FROPA
AND INCREASE FURTHER...POSSIBLY GUSTING TO 40KT EARLY TOMORROW
EVENING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS THROUGH LATE TONIGHT.
* HIGH CONFIDENCE IN A PERIOD OF A WINTRY MIX OF PCPN DURG THE
EARLY MORNING HOURS...BUT LOWER CONFIDENCE IN TIMING AND
DURATION OF THE WINTRY MIX PCPN.
* HIGH CONFIDENCE THAT PCPN WILL CHANGE OVER TO ALL RAIN BY LATE
MORNING...BUT LOWER CONFIDENCE IN EXACT TIMING.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN VISBY TRENDS...ESPECIALLY RELATED TO
THE CHANCE FOR IFR/LIFR VIS IN FOG DEVELOPING LATE TOMORROW
MORNING INTO TOMORROW AFTERNOON.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...RAIN OR SNOW SHOWERS...WITH POSSIBLE MVFR
CONDITIONS. VERY STRONG SOUTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS
UP TO 50 MPH
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF LIGHT SNOW.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
305 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NO CONCERNS IN THE NEAR TERM.
* WINTRY MIX OF PCPN BEGINNING DURG THE PRE-DAWN HOURS...LIKELY
SN/FZRA...THOUGH THERE IS A CHANCE THAT SOME IP COULD MIX IN
BRIEFLY. AMOUNT OF ICE ACCUMULATION IS UNCERTAIN.
* TIMING OF CHANGEOVER FROM WINTRY MIX TO ALL RAIN. LIKELY BY ARND
12Z...BUT EXACT TIMING IS STILL UNCERTAIN.
* VIS MAY DROP TO IFR...OR POSSIBLY LIFR...IN BR/FG BY LATE
MORNING OR EARLY AFTERNOON.
* CHANCE OF ISOLD/EMBEDDED TSRA LATE MORNING THROUGH EARLY
AFTERNOON UNTIL FRONTAL PASSAGE.
* WINDS SHIFTING TO SSWLY-SWLY BY EARLY AFTERNOON...STRENGTHENING
AND BECMG GUSTY TO ARND 30KT IN THE LATE AFTERNOON. GUSTS COULD
POSSIBLY BE EVEN HIGHER LATE AFTERNOON/EARLY EVENING.
KREIN
//DISCUSSION...UPDATED 18Z...UPDATED 1845Z...
QUIET CONDITIONS THROUGH LATE TONIGHT. CLEAR SKIES WILL GIVE WAY
TO INCREASING MID AND HIGH CLOUD AS A COMPLEX WEATHER SYSTEM
DEVELOPS OVER THE CENTRAL PLAINS AND CLOUD COVER BEGINS TO RACE
OUT AHEAD OF THE DOUBLE BARRELED LOW PRESSURE SYSTEM. OF MAIN
CONCERN TO NRN IL/NWRN INDIANA WILL BE THE TRACK AND DEVELOPMENT
OF THE SOUTHERN OF THE 2 LOWS...WHICH IS EXPECTED TO INITIALLY
DEVELOP OVER THE SOUTH HIGH PLAINS AND AND RAPIDLY DEEPEN AS IT
TRACKS THROUGH THE MIDDLE MISSISSIPPI VALLEY TO EASTERN WISCONSIN
BY EARLY TOMORROW EVENING.
THIS SYSTEM WILL BRING A COMPLEX WEATHER SCENARIO TO THE TERMINALS
WHICH WILL BE HIGHLY DEPENDANT ON THE EXACT TRACK OF THE
SYSTEM...AS WELL AS THE IMPACT OF THE DENSE SNOW PACK OVER THE
REGION. BASED ON THE CURRENTLY EXPECTED TRACK...AN ASSOCIATED WARM
FRONT WOULD LIFT NWD THROUGH THE REGION. WITH WARMER AIR ALOFT
OVERRIDING THE COLDER AIR AND SNOW PACK AT THE SFC...PCPN SHOULD
START OUT AS EITHER ALL SNOW...OR A WINTRY MIX OF
FZRA/IP/SN/RA...WHICH WILL BE HIGHLY DEPENDANT ON THE DEPTH AND
DURATION OF A SUB-FREEZING LAYER AT THE SFC...WITH THE DENSE
SNOWPACK POSSIBLY HELPING TO KEEP SFC TEMPS AT ARND THE FREEZING
MARK. THERE ARE PLEANTY OF QUESTIONS MARKS WITH THIS
SYSTEM...AMONG THEM BEING THE DURATION OF THE FREEZING AND FROZEN
PCPN TYPES. THE SYSTEM IS EXPECTED TO BE VERY FAST-MOVING...BUT
VERY DYNAMIC. THE SPEED OF THE SYSTEM WILL HELP LIMIT THE DURATION
OF THE FREEZING/FROZEN PCPN AND SNOW OR ICE ACCUMULATIONS WOULD BE
MINOR...BUT THE DYNAMICS OF THE SYSTEM COULD HELP GENERATE SOME
ADDITIONAL DYNAMIC COOLING...WHICH WOULD DELAY A CHAGEOVER FROM
SNOW TO FREEZING PCPN AND ADD TO THE SNOW ACCUMULATION TOTALS.
BEST ESTIMATION AT THIS POINT WOULD BE THAT ICE AND SNOW
ACCUMULATIONS WILL BE RELATIVELY MINOR...BUT ENOUGH TO HAVE A
SIGNIFICANT IMPACT ON OPERATIONS EVEN IF THE DURATION IS LIMITED
TO 2-3 HOURS. HAVE RELATIVELY HIGH CONFIDENCE THAT PCPN WILL
CHANGE OVER TO ALL RAIN AS THE WARM FRONT LIFTS NORTH OF THE
TERMINALS. HOWEVER...THIS WILL BRING THE NEXT SIGNIFICANT CONCERN
OF HEAVY RAIN WITH EMBEDDED THUNDERSTORMS. BASED ON THE CURRENTLY
ANTICIPATED TRACK OF THE SYSTEM...WITH THE MAIN SFC LOW PASSING
THROUGH FAR NWRN IL WOULD PUT THE TERMINAL AREAS INTO A WARM
SECTOR OF THE SYSTEM...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT. THE STRONGEST FORCING AND INSTABILITY SHOULD FOCUS THE MOST
EXTENSIVE AND STRONGEST THUNDERSTORMS TO THE SOUTHEAST OF THE
TERMINALS...BUT FORCING AND INSTABILITY SHOULD BE SUFFICIENT FOR
ISOLATED/EMBEDDED THUNDER FROM LATE MORNING AND THROUGH THE
AFTERNOON HOURS. IN ADDITION TO THE RAIN AND THUNDER
CONCERNS...ALSO HAVE CONCERN FOR THE POTENTIAL FOR DENSE FOG WITH
THE ADVECTION OF WARM/MOIST AIR OVER THE SNOW PACK...WHICH WILL
ALSO HAVE INCREASING MOISTURE CONTENT AS THE SNOW ABSORBS THE
FALLING RAIN. WITH HIGH DEWPOINT WARM AIR OVERSPREADING THE
SNOW...THERE IS A CONCERN THAT DENSE FOG COULD DEVELOP BY LATE
MORNING/EARLY AFTERNOON...EVEN WITH STRENGTHENING SELY-SLY WINDS.
HAVE LIMITED THE LOWER EXTENT OF THE VISBY TO 3/4SM TO 1SM FOR
TOMORROW...BUT THERE IS THE POTENTIAL FOR PERIODS OF VISBY
DROPPING TO 1/4SM IN FOG UNTIL THE PASSAGE OF THE STRONG COLD
FRONT TOMORROW EVENING.
THE THIRD CONCERN WILL THEN BECOME WINDS. SELY WINDS WILL BEGIN
TO INCREASE THROUGH THE MORNING WITH THE APPROACH OF THE COLD
FRONT...WITH SELY-SLY WINDS INCREASING AND BECMG GUSTY APPROACHING
30KT LATE THIS AFTERNOON. WHILE IT WILL BE AFTER THE CURRENT TAF
PERIOD...WINDS WILL SHIFT THROUGH SWLY TO WLY FOLLOWING THE FROPA
AND INCREASE FURTHER...POSSIBLY GUSTING TO 40KT EARLY TOMORROW
EVENING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS THROUGH LATE TONIGHT.
* HIGH CONFIDENCE IN A PERIOD OF A WINTRY MIX OF PCPN DURG THE
EARLY MORNING HOURS...BUT LOWER CONFIDENCE IN TIMING AND
DURATION OF THE WINTRY MIX PCPN.
* HIGH CONFIDENCE THAT PCPN WILL CHANGE OVER TO ALL RAIN BY LATE
MORNING...BUT LOWER CONFIDENCE IN EXACT TIMING.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN VISBY TRENDS...ESPECIALLY RELATED TO
THE CHANCE FOR IFR/LIFR VIS IN FOG DEVELOPING LATE TOMORROW
MORNING INTO TOMORROW AFTERNOON.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...RAIN OR SNOW SHOWERS...WITH POSSIBLE MVFR
CONDITIONS. VERY STRONG SOUTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS
UP TO 50 MPH
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF LIGHT SNOW.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.MARINE...
417 AM CST
SURFACE TROUGH AND FRONTAL BOUNDARY CONTINUE TO SHIFT EAST OF THE
LAKE EARLY THIS MORNING...AS WINDS SETTLE BACK TO A WEST/NORTHWEST
WIND AROUND 10 TO 20 KT ACROSS THE ENTIRE LAKE. AS HIGH PRESSURE
OVER THE CENTRAL PLAINS MOVES EAST THROUGH THE MID MISSISSIPPI
VALLEY TODAY...WINDS WILL TURN BACK TO THE SOUTHWEST. THIS HIGH
WILL THEN PUSH EAST TO THE ATLANTIC COAST TONIGHT WHILE WINDS
BECOME MORE SOUTHERLY...AND BEGIN TO INCREASE. EXPECT SOUTHEAST
WINDS TO INCREASE DURING THE DAY THURSDAY AS DEVELOPING LOW
PRESSURE MOVES OUT OF THE CENTRAL PLAINS NORTHEAST TO THE UPPER
MIDWEST AND WESTERN GREAT LAKES. GALES WILL BECOME MORE LIKELY BY
LATE THURSDAY AFTERNOON OVER THE OPEN WATERS AND NEARSHORE...WITH
THESE SPEEDS CONTINUING INTO THE NIGHT AS THE LOW CONTINUES
NORTHEAST ACROSS THE GREAT LAKES REGION WHILE FURTHER
STRENGTHENING. ALTHOUGH HIGH END GALES WILL CONTINUE FOR THE
NEARSHORE...SPEEDS WILL LIKELY INCREASE TO STORM FORCE AFTER
MIDNIGHT FOR THE OPEN WATERS. STORM FORCE WINDS ARE ANTICIPATED
INTO FRIDAY AFTERNOON BEFORE WEAKENING BACK TO GALES...WITH THESE
GALES POSSIBLY CONTINUING FRIDAY NIGHT. GALE/STORM WATCHES HAVE
BEEN ISSUED FOR BOTH THE NEARSHORE AND OPEN WATERS DURING THESE
PERIODS. CONFIDENCE IS NOT TOO HIGH WITH REGARDS TO THE RESULTANT
WAVE HEIGHTS DUE TO ICE COVERAGE AND FETCH. ALTHOUGH WITH WARMER
AIR TEMPS EXPECTED TODAY INTO THURSDAY...ICE COVERAGE COULD
DECREASE SOME WITH THE POTENTIAL FOR HIGHER WAVES THAN WHAT IS
CURRENTLY FORECAST...ESPECIALLY WITH STORM FORCE WINDS TO 55 KT
POSSIBLE.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
231 PM MST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
LATEST RAP UPPER LEVEL ANALYSIS SHOWS TROUGH CENTERED OVER
SASKATCHEWAN CANADA WITH MEAN AXIS EXTENDING SOUTH OVER MONTANA
AND UTAH. AT THE SURFACE A COLD FRONT CURRENTLY EXTENDS FROM THE
DAKOTAS ACROSS CENTRAL WYOMING AND CENTRAL UTAH. OVER EASTERN
COLORADO A 994MB SURFACE LOW HAS DEVELOPED WITH TIGHT SOUTHERLY
GRADIENT IN PLACE OVER OUR CWA.
REGARDING WINTER WEATHER ADVISORY TONIGHT...
WINTER STORM SHOULD DEVELOPING AS TROUGH MOVES OUT OF NORTHERN
ROCKIES. UPPER LEVEL FORCING SHOULD INCREASE THIS EVENING WITH
COLD FRONT PUSHING SOUTH INTO NW PART OF THE CWA BY ABOUT
03Z...AND THEN ACROSS THE REMAINING CWA THROUGH 09Z. WHILE THERE
ISNT REALLY STRONG CAA BEHIND THIS FRONT...CHANGEOVER SHOULD BE
RELATIVELY QUICK FOR ALL BUT THE FAR SOUTHEAST AS SATURATION TO
WETBULB TEMP WOULD SUPPORT SNOW REACHING SURFACE. BEHIND THIS
FRONT THE COMBINATION OF VERY HIGH 3-6 HOUR PRESSURE RISES AND
STEEP LAPSE RATES WILL HELP MIX A VERY STRONG LLJ TO THE
SURFACE...WITH NEAR WARNING CRITERIA WINDS (60 MPH GUSTS)
POSSIBLE. GUIDANCE HAS GENERALLY TRENDED BACK A LITTLE ON WINDS
ALOFT COMPARED TO A DAY AGO...BUT CONFIDENCE IS IS STILL HIGH FOR
GUSTS AROUND 55 MPH (ISOLATED 60MPH). SHORT RANGE GUIDANCE
(RAP/HRRR) CONTINUES TO INDICATE A VERY INTENSE AND PROGRESSIVE
BAND OF PRECIP MOVING FROM THE NORTHWEST TO THE SOUTHEAST TONIGHT.
THIS GENERALLY MATCH RECENT TRENDS ON GUIDANCE (THOUGH THERE ARE
STILL MINOR DIFFERENCES ON QPF AMOUNTS AND POSITION).
TIMING/POSITION OF DEFORMATION PRECIP BAND WILL DETERMINE LOCATION
OF HIGHER SNOWFALL RATES AND TIMING OF POSSIBLE WHITEOUT
CONDITIONS. SNOW RATES WITH THIS BAND COULD BE QUITE INTENSE AS
MODEL CROSS SECTION CONTINUE TO INDICATE AN UNSTABLE LAYER
ASSOCIATED WITH THE BAND...WHICH COULD LEAD TO SNOWFALL RATES OF
AROUND 2" PER HOUR. DUE TO THE PROGRESSIVE NATURE OF THIS BAND THE
WORST VISIBILITIES ARE NOT EXPECTED TO MEET 3HR REQUIREMENT FOR
BLIZZARD WARNING...AND AMOUNTS WITH BAND SHOULD STILL BE AROUND 3"
MAX. NO CHANGE TO CURRENT WINTER WEATHER ADVISORY AT THIS
TIME...AND WILL ALLOW SUBSEQUENT SHIFT TO MONITOR FOR CHANGES IN
UPSTREAM TRENDS.
THURSDAY...LARGE SCALE SUBSIDENCE WILL SUPPORT RAPIDLY CLEARING
CONDITIONS FROM THE WEST TO THE EAST...WITH ALL PRECIP COMING TO
AN END AROUND SUNRISE. IT STILL LOOKS LIKE THERE WILL BE A BRIEF
REPRIEVE FROM THE STRONGEST WINDS THURSDAY MORNING BEFORE DAYTIME
MIXING BRINGS STRONGER WINDS BACK TO THE SURFACE. WINDS
ALOFT/MIXING HEIGHTS MIGHT SUPPORT NEAR WARNING CRITERIA BEING MET.
IT IS NOT A SLAM DUNK THAT WE WILL REACH WARNING CRITERIA
EVERYWHERE...AND CURRENT WIND ADVISORY THURSDAY COVERS WINDS TO 55
MPH (WHICH GENERALLY MATCHES CURRENT GUIDANCE). NO CHANGE TO WIND
ADVISORY WAS PLANNED WITH THIS UPDATE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
THURSDAY NIGHT-SATURDAY...DRY CONDITIONS EXPECTED WITH VARYING
AMOUNTS OF CLOUDINESS...THICK AT TIMES. BREEZY TO PERHAPS WINDY
CONDITIONS FROM THE NORTHWEST LATE FRIDAY MORNING THROUGH THE
AFTERNOON. HIGHS FRIDAY UPPER 40S FAR NORTHWEST WITH 50S OVER THE
REMAINDER OF THE AREA. FOR SATURDAY COOLER BEHIND FRIDAYS FRONTAL
PASSAGE WITH UPPER 30S NORTHWEST TO MID/UPPER 40S FAR
SOUTH/SOUTHEAST. LOWS THROUGH THE PERIOD GENERALLY IN THE 20S.
SATURDAY NIGHT-WEDNESDAY NIGHT...FORECAST AREA UNDER NORTHWEST FLOW
THROUGH THE PERIOD. WILL HAVE A CHANCE OF SOME LIGHT PRECIPITATION
SATURDAY NIGHT AS A BATCH OF 850-500 MOISTURE MOVES ACROSS AREAS
GENERALLY ALONG AND NORTH OF THE INTERSTATE. SHOULD HAVE A LULL IN
ACTIVITY SUNDAY WITH A SMALL CHANCE OF PRECIP ACROSS THE NORTHEAST
SUNDAY NIGHT INTO MONDAY. COULD SEE ANOTHER ROUND OF LIGHT PRECIP
MONDAY NIGHT A BIT FURTHER WEST THEN PREVIOUS DAYS NEAR PROXIMITY
TO FAVORABLE PORTION OF UPPER JET. TUESDAY AND WEDNESDAY LOOK TO
BE DRY.
HIGH TEMPERATURES A BIT BELOW NORMAL SUNDAY THROUGH TUESDAY WITH
NEAR NORMAL READINGS WEDNESDAY. LOWS THROUGH THE PERIOD PRETTY
CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1032 AM MST WED FEB 19 2014
GUSTY WINDS WILL CONTINUE THROUGH MOST OF THE PERIOD WITH
STRONGEST WINDS TONIGHT WITH FRONTAL PASSAGE WHEN GUSTS 45KT ARE
EXPECTED IMMEDIATELY BEHIND FRONT (POSSIBLY 50KT). THERE WILL BE
TWO LULLS IN THE WINDS AS SURFACE GRADIENT SHIFTS AND GUSTS
BRIEFLY DIMINISH...WITH THE FIRST LATE THIS AFTERNOON/EVENING AND
THEN ANOTHER AROUND SUNRISE THURSDAY.
FLIGHT CONDITIONS WILL DETERIORATE RAPIDLY AFTER 06Z TONIGHT WITH
LIFR/VILFR CONDITIONS POSSIBLE FOR A BRIEF PERIOD AROUND 08-09Z AS
A MODERATE BAND OF SNOW AND BLOWING SNOW MOVES OVER BOTH
TERMINALS. I SHOWED A TRANSITION TO IFR PREVAILING IN THE CURRENT
TAFS...AND IT IS STILL TOO FAR OUT TO ADD TEMPO...HOWEVER THIS
WILL LIKELY NEED TO BE ADDED DURING SUBSEQUENT SCHEDULED UPDATES
TO TIME OUT THE PERIOD OF LOW CONDITIONS. THIS BAND WILL MOVE
THROUGH THE REGION QUICK ENOUGH WITH STABLE AIR BEHIND IT
SUPPORTING RAPIDLY CLEARING CONDITIONS TOWARDS 12Z AT BOTH
TERMINALS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 8 PM MST /9 PM CST/ THIS EVENING TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-014-027-041.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 1 AM TO 8 AM CST THURSDAY FOR
KSZ003-004-015-016-028-029-042.
CO...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 6 AM MST
THURSDAY FOR COZ090>092.
WIND ADVISORY FROM 9 AM TO 5 PM MST THURSDAY FOR COZ090>092.
NE...WINTER WEATHER ADVISORY FROM 8 PM MST /9 PM CST/ THIS EVENING TO
6 AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...DR
AREA FORECAST DISCUSSION
NWS WICHITA KS
209 PM CST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 205 PM CST WED FEB 19 2014
THE MAIN FORECAST CONCERNS WILL BE THE POTENTIAL FOR STRONG-SEVERE
STORMS IN SOUTHEAST KS TONIGHT...VERY STRONG NORTHWEST WINDS
THURSDAY...AND SNOW/REDUCED VISIBILITIES IN CENTRAL KS EARLY
THURSDAY. A STRONG SHORTWAVE TROUGH/PV ANOMALY OVER THE GREAT
BASIN THIS AFTERNOON...WILL TRANSLATE EASTWARD ACROSS THE CENTRAL
PLAINS LATER TONIGHT THROUGH THURSDAY. A 45-50 KNOT SOUTHERLY LOW-
LEVEL JET WILL INDUCE MOISTURE TRANSPORT NORTHWARD THROUGH EASTERN
KANSAS THROUGH TONIGHT. SCATTERED ELEVATED SHOWERS/THUNDERSTORMS
WILL CONTINUE TO DEVELOP OVER SOUTHEASTERN KS THIS AFTERNOON INTO
THIS EVENING WHILE GRADUALLY INTENSIFYING AS BETTER ELEVATED
INSTABILITY ARRIVES. THE ELEVATED INSTABILITY/STRONG SHEAR WILL
LIKELY RESULT IN A FEW STRONG-SEVERE STORMS THIS EVENING WITH
HAIL...BEFORE THE BRUNT OF THIS ACTIVITY SHIFTS NORTHEAST OUT OF
SOUTHEAST KS. THERE COULD BE RENEWED THUNDERSTORM DEVELOPMENT IN
SOUTHEAST KS VERY LATE TONIGHT/EARLY THURSDAY MORNING...AS THE
STRONG PV ANOMALY MOVES IN WITH VERY STEEP MID-LEVEL LAPSE RATES.
AGAIN LARGE HAIL WILL BE THE PRIMARY HAZARD.
THE PRESSURE GRADIENT WILL TIGHTEN DRAMATICALLY BEHIND THE EASTWARD
MOVING COLD FRONT VERY LATE TONIGHT INTO THURSDAY. STEEP LOW-LEVEL
LAPSE RATES WILL PROMOTE THE MIXDOWN OF VERY STRONG 850 MB WINDS
BEHIND THE COLD FRONT. WE PLAN TO UPGRADE THE CURRENT HIGH WIND
WATCH TO A WARNING FOR ALONG/W OF HIGHWAY 14 WHERE DAMAGING WINDS
APPEAR MOST LIKELY...WHILE MAINTAINING THE CURRENT WIND ADVISORY
ALONG/E OF I-135 THURSDAY. COLD AIR ADVECTION WILL CHANGE THE
PRECIPITATION FROM RAIN TO A BRIEF PERIOD (2-4 HOURS) OF SNOW IN
CENTRAL KS VERY LATE TONIGHT INTO MID MORNING THURSDAY. THE
COMBINATION OF SNOW (UP TO 1 INCH ACCUMULATION) AND VERY STRONG
WINDS WILL LIKELY RESULT IN BLOWING SNOW AND SHARPLY REDUCED
VISIBILITIES SO WILL CARRY A WINTER WEATHER ADVISORY FOR PART OF
CENTRAL KS. STRONG SUBSIDENCE WILL SET IN ON THE BACKSIDE OF THE
UPPER TROUGH THURSDAY AFTERNOON ENDING PRECIPITATION IN OUR AREA.
MOSTLY CLEAR SKIES EXPECTED THURSDAY NIGHT INTO FRIDAY. WESTERLY
WINDS WILL INDUCE DOWNSLOPE WARMING FRIDAY AND THIS WILL LEAD TO
ABOVE NORMAL HIGHS IN THE UPPER 50S/LOW 60S. AN INITIAL SHALLOW
SURGE OF COLDER AIR WILL ARRIVE FRIDAY NIGHT INTO SATURDAY RESULTING
IN TEMPERATURES CLOSER TO SEASONAL AVERAGES.
JMC
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 205 PM CST WED FEB 19 2014
UPPER LEVEL RIDGING WILL DEVELOP NORTHWARD FROM THE WEST COAST UP
THROUGH WESTERN CANADA/EASTERN ALASKA. MEANWHILE A LARGE UPPER
TROUGH WILL CONTINUE TO DEVELOP OVER CENTRAL/EASTERN CANADA DOWN
THROUGH THE EASTERN CONUS. THIS PATTERN WILL BE CONDUCIVE TO COLD
AIR SURGES FROM WESTERN CANADA INTO THE CENTRAL PLAINS. ONE SURGE IS
PROGGED MONDAY NIGHT INTO TUESDAY...WITH A SECOND SURGE TUESDAY
NIGHT INTO WEDNESDAY. WE EXPECT SLIGHTLY BELOW NORMAL TEMPERATURES
DURING THE PERIOD WITH MAINLY DRY WEATHER PREVAILING.
JMC
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1118 AM CST WED FEB 19 2014
THERE ARE TWO TO THREE PRIMARY CONCERNS RELATED TO ONE UPPER LEVEL
SYSTEM. AHEAD OF THE SURFACE FRONT/WAVE MOISTURE IS EXPECTED TO
STREAM NORTHWARD DURING THE AFTERNOON HOURS TODAY. THE MOISTURE
TRANSPORT WILL BE STRONGEST LATE THIS AFTERNOON AND EVENING.
LIKING HOW THE HRRR EVOLVES CONVECTION THIS AFTERNOON/EVENING.
THINK THE BEST CHANCES FOR CONVECTION WILL BE ALONG THE NOSE OF
THE MOISTURE TRANSPORT AND THAT IT WILL QUICKLY SHIFT FROM
SOUTHEAST KANSAS NORTHEASTWARD. HAVE KEPT THE VCTS IN AT KCNU FOR
THE EVENING WITH A STRUGGLE OF ACTUAL TIMING OF THE PREVAILING
STORMS. ONLY PUT CONVECTION IN AT KCNU...BUT THERE COULD BE SOME
ACTIVITY AS FAR WEST AS KICT...ALTHOUGH CONFIDENCE IS LOW FOR THIS
TO OCCUR.
THE SECOND CONCERN IS A VERY STRONG PRESSURE GRADIENT WILL IMPACT
THE REGION BEHIND THE COLD FRONT. THIS GRADIENT WILL CAUSE WINDS
TO BECOME NORTHWESTERLY AND SUSTAINED AROUND 30-35KTS AND GUSTS TO
40+ KTS.
THE THIRD CONCERN IS WINTRY PRECIPITATION IMPACTING GENERALLY KRSL
AND KSLN IN THE MORNING HOURS. THIS WILL BE IN COMBINATION WITH
THE VERY STRONG WINDS AND WILL CAUSE A QUICK ACCUMULATION OF SOME
SNOW WITH BLOWING SNOW REDUCING VISIBILITIES.
BILLINGS WRIGHT
&&
.FIRE WEATHER...
ISSUED AT 205 PM CST WED FEB 19 2014
THE COMBINATION OF DRIER AIR OVERSPREADING THE REGION AND STRONG
NORTHWEST WINDS WILL RESULT IN VERY HIGH GRASSLAND FIRE DANGER
CONDITIONS REGION-WIDE THURSDAY. MINIMUM AFTERNOON RELATIVE
HUMIDITIES OF 25-35% ARE EXPECTED.
JMC
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 39 48 27 60 / 30 30 0 0
HUTCHINSON 35 48 27 59 / 60 60 0 0
NEWTON 37 47 28 59 / 50 40 0 0
ELDORADO 42 48 27 59 / 50 30 0 0
WINFIELD-KWLD 43 51 27 61 / 30 30 0 0
RUSSELL 33 46 26 58 / 70 70 0 10
GREAT BEND 34 47 26 58 / 60 60 0 0
SALINA 34 45 27 57 / 80 80 0 10
MCPHERSON 35 47 27 58 / 70 70 0 0
COFFEYVILLE 52 56 29 62 / 60 40 0 0
CHANUTE 49 53 26 58 / 60 50 0 10
IOLA 48 52 27 57 / 70 50 0 10
PARSONS-KPPF 51 55 27 60 / 60 40 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 6 AM TO 4 PM CST THURSDAY FOR KSZ049-051>053-
068>072-083-092>096-098>100.
HIGH WIND WARNING FROM 3 AM TO 10 AM CST THURSDAY FOR KSZ032-033-
047-048-050-067-082-091.
WINTER WEATHER ADVISORY FROM 3 AM TO 10 AM CST THURSDAY FOR
KSZ032-033-047>051.
WIND ADVISORY FROM 10 AM TO 4 PM CST THURSDAY FOR KSZ032-033-047-
048-050-067-082-091.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1128 AM CST WED FEB 19 2014
...UPDATED FOR AVIATION DISCUSSION...
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 312 AM CST WED FEB 19 2014
ABOVE NORMAL TEMPERATURES EXPECTED AGAIN TODAY BUT NOT AS WARM AS
YESTERDAY WITH MORE CLOUDS SPREADING ACROSS THE REGION.
MEANWHILE...MOISTURE TRANSPORT WILL RAMP UP ACROSS EASTERN KANSAS
FOR THIS AFTERNOON INTO TONIGHT AHEAD OF FLEET-FOOTED UPPER WAVE
CURRENTLY OVER THE PACIFIC NORTHWEST. SCATTERED THUNDERSTORMS LOOK
TO DEVELOP THIS AFTERNOON...MAINLY FOR LOCATIONS EAST OF THE KANSAS
TURNPIKE. THE COMBINATION OF ELEVATED INSTABILITY AND STRONG SHEAR
ALOFT COULD GIVE WAY TO A FEW STRONG/SEVERE THUNDERSTORMS WITH HAIL
BEING THE PRIMARY HAZARD. OTHERWISE SURFACE LOW PRESSURE WILL
UNDERGO EXPLOSIVE CYCLOGENESIS TONIGHT WHICH WILL CAUSE A RAPID
TIGHTENING OF THE PRESSURE GRADIENT WINDS ON THE BACKSIDE FOR LATE
TONIGHT...THEN SPREAD EASTWARD ACROSS THE REGION ON THURSDAY. WE
WILL HOIST A HIGH WIND WATCH FOR LOCATIONS THAT COULD SEE WIND
SPEEDS REACHING EXTREME LEVELS(LATE TONIGHT-THURSDAY MORNING) AND
CARRY A WIND ADVISORY FOR THE REMAINDER OF THE AREA ON THURSDAY. THE
COLDER AIR WILL CHANGE THE PRECIP TYPE OVER TO SNOW ACROSS CENTRAL
KANSAS FOR LATE TONIGHT INTO THURSDAY MORNING. IT LOOKS TO BE A
BRIEF PERIOD OF SNOW FOR CENTRAL KANSAS WITH THE DEFORMATION ZONE
RACING EASTWARD...BUT IF THE SNOW COMES DOWN AT A HIGH ENOUGH RATE
COMBINED WITH THE EXTREME WINDS THIS COULD DROP VISIBILITIES
SIGNIFICANTLY AND LATER SHIFTS COULD END UP HOISTING A WINTER
WEATHER ADVISORY FOR THIS HAZARD. THE PRECIP WILL END QUICKLY AS
STRONG SUBSIDENCE SPREADS OVER THE AREA FOR THURSDAY AFTERNOON.
A NICE REBOUND WILL BE IN STORE FOR THE AREA ON FRIDAY AS PREMIUM
DOWNSLOPE EFFECTS BOOSTS DAYTIME HIGHS ABOVE NORMAL.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 312 AM CST WED FEB 19 2014
WE SHOULD SEE A LITTLE COOL DOWN FOR THE WEEKEND WITH A MORE
NOTICEABLE COOL DOWN ARRIVING ON MONDAY NIGHT INTO TUESDAY...AS NEXT
SURGE OF COLDER AIR PUSHES SOUTHWARD INTO KANSAS.
JAKUB
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1118 AM CST WED FEB 19 2014
THERE ARE TWO TO THREE PRIMARY CONCERNS RELATED TO ONE UPPER LEVEL
SYSTEM. AHEAD OF THE SURFACE FRONT/WAVE MOISTURE IS EXPECTED TO
STREAM NORTHWARD DURING THE AFTERNOON HOURS TODAY. THE MOISTURE
TRANSPORT WILL BE STRONGEST LATE THIS AFTERNOON AND EVENING.
LIKING HOW THE HRRR EVOLVES CONVECTION THIS AFTERNOON/EVENING.
THINK THE BEST CHANCES FOR CONVECTION WILL BE ALONG THE NOSE OF
THE MOISTURE TRANSPORT AND THAT IT WILL QUICKLY SHIFT FROM
SOUTHEAST KANSAS NORTHEASTWARD. HAVE KEPT THE VCTS IN AT KCNU FOR
THE EVENING WITH A STRUGGLE OF ACTUAL TIMING OF THE PREVAILING
STORMS. ONLY PUT CONVECTION IN AT KCNU...BUT THERE COULD BE SOME
ACTIVITY AS FAR WEST AS KICT...ALTHOUGH CONFIDENCE IS LOW FOR THIS
TO OCCUR.
THE SECOND CONCERN IS A VERY STRONG PRESSURE GRADIENT WILL IMPACT
THE REGION BEHIND THE COLD FRONT. THIS GRADIENT WILL CAUSE WINDS
TO BECOME NORTHWESTERLY AND SUSTAINED AROUND 30-35KTS AND GUSTS TO
40+ KTS.
THE THIRD CONCERN IS WINTRY PRECIPITATION IMPACTING GENERALLY KRSL
AND KSLN IN THE MORNING HOURS. THIS WILL BE IN COMBINATION WITH
THE VERY STRONG WINDS AND WILL CAUSE A QUICK ACCUMULATION OF SOME
SNOW WITH BLOWING SNOW REDUCING VISIBILITIES.
BILLINGS WRIGHT
&&
.FIRE WEATHER...
ISSUED AT 312 AM CST WED FEB 19 2014
THE COMBINATION OF DRIER AIR OVERSPREADING THE REGION AND STRONG
NORTHWEST WILL GIVE WAY TO VERY HIGH GRASSLAND FIRE DANGER
CONDITIONS ACROSS THE ENTIRE REGION THURSDAY AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 59 38 48 28 / 20 30 30 0
HUTCHINSON 58 35 48 28 / 20 60 60 0
NEWTON 57 36 46 29 / 20 60 60 0
ELDORADO 59 39 47 28 / 30 60 60 10
WINFIELD-KWLD 61 41 51 28 / 20 30 30 0
RUSSELL 58 34 46 27 / 10 70 70 0
GREAT BEND 58 35 47 27 / 10 60 60 0
SALINA 57 35 45 28 / 20 80 80 0
MCPHERSON 57 35 47 28 / 20 70 70 0
COFFEYVILLE 64 51 55 30 / 50 60 60 10
CHANUTE 60 47 52 27 / 50 70 70 10
IOLA 59 46 51 28 / 50 80 80 10
PARSONS-KPPF 62 50 54 28 / 50 70 70 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 6 AM TO 4 PM CST THURSDAY FOR KSZ049-051>053-
068>072-083-092>096-098>100.
HIGH WIND WATCH FROM LATE TONIGHT THROUGH THURSDAY AFTERNOON FOR
KSZ032-033-047-048-050-067-082-091.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1217 AM MST WED FEB 19 2014
.UPDATE...
ISSUED AT 948 PM MST TUE FEB 18 2014
UPDATED THE FORECAST FOR LATEST THINKING ON THE UPCOMING WIND AND
SNOW EVENT TOMORROW NIGHT. MAINTAINED/REFRESHED THE WSW...HWO AND
ZFP BY UPDATING THE TIMING OF THE RAIN/SNOW TRANSITION AND THE
ARRIVAL OF STRONGEST WINDS/ASSOCIATED BLOWING SNOW THREAT.
PRESSURE RISES BEHIND THE COLD FRONT WEDNESDAY EVENING/NIGHT ARE
VERY IMPRESSIVE...ON THE ORDER OF 12-16 MB OVER 3-6 HOURS. THIS ONLY
INCREASES CONFIDENCE IN PROBLEMS WITH STRONG WINDS TOMORROW NIGHT. MODELS
BRING PRECIPITATION INTO THE AREA BEHIND THE FRONT WITHOUT MUCH
AHEAD OF IT. THIS IS DUE TO SOME DRY AIR AT THE LOW LEVELS AND
ALOFT WITH A DRY AIR INTRUSION. BEHIND THE FRONT...THE ATMOSPHERIC
PROFILE SATURATES AND PRECIPITATION WILL BEGIN TO REACH THE
GROUND. IT SEEMS THERE WILL BE A STRONG BAND OF SNOW THAT WILL
DEVELOP BEHIND THE FRONT AND TRANSITION ACROSS THE AREA FAIRLY
QUICKLY. UNDER THE BAND...SNOWFALL RATES AND WINDS WILL BRING
PROBLEMS WITH BLOWING SNOW AND DRIFTING. VISIBILITIES WILL BE NEAR
ZERO AT TIMES. DUE TO THE QUICK MOVEMENT OF THE BAND...SNOWFALL
AMOUNTS ARE NOT EXPECTED TO BE NEARLY AS HIGH AS RECENT BANDED
SNOWFALL EVENTS. AT THIS POINT...ONE TO THREE INCHES OF SNOW IS
EXPECTED WITH THE POTENTIAL TO SEE CLOSER TO 4 INCHES OVER
SOUTHWEST NEBRASKA. VERY COMPLICATED SCENARIO AS THE WINDS MAY
APPROACH HIGH WIND WARNING CRITERIA BUT BLIZZARD CONDITIONS MAY
NOT BE MET FOR THE FULL THREE HOUR REQUIREMENT. THEREFORE...THE
ADVISORY WAS ISSUED AS WINTER STORM CRITERIA WOULD NOT BE MET AS
WELL. HIGHLIGHT CHANGES MAY BE NEEDED CLOSER TO THE EVENT
DEPENDING ON DURATION OF HEAVIER SNOW AND THUS LOWER VISIBILITIES
OR THE STRENGTH OF THE WINDS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 145 PM MST TUE FEB 18 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS INDICATE SHORTWAVE TROUGH OVER
EASTERN NEBRASKA/KANSAS WITH SHORTWAVE RIDGE OVER THE GREAT BASIN
AND NORTHERN ROCKIES. A COLD FRONT (WHICH SHOWS UP BETTER WITH
VERTICAL THICKNESS FIELD) IS MOVING SOUTH TO THE KS/NE BORDER WITH A
PREFRONTAL SURFACE TROUGH AXIS NOW ACROSS CENTRAL KANSAS.
THIS AFTERNOON...STRONG PRESSURE GRADIENT HAS LED TO DEVELOPMENT OF
WIND GUSTS 45-60 MPH ACROSS THE NORTHERN HALF OF THE CWA...WITH
WINDS JUST STARTING TO COME UP ACROSS THE EAST AND SOUTH OVER THE
LAST HOUR. STRONGEST GUSTS WERE ASSOCIATED WITH INITIAL SURGE AS
SURFACE TROUGH SHIFTED SOUTH AND 3HR PRESSURE RISES BEHIND COLD
FRONT PEAKED AROUND 4MB. WINDS HAVE STABILIZED WITHIN ADVISORY
CRITERIA AFTER THIS INITIAL SURGE...SO DECISION WAS MADE TO HOLD
ONTO ADVISORY. RED FLAG CONDITIONS ARE BEING MET AT MOST OF WARNED
AREA...THOUGH INCREASING TD VALUES FROM THE NORTH ARE KEEPING RH
VALUES CLOSER TO 30 PERCENT ACROSS THE NORTHERN PART OF THE RFW. WE
MAY NOT MEET THE HIGH END THRESHOLD FOR RED FLAG CONDITIONS...
HOWEVER WITH THE MAGNITUDE OF WIND...I SEE NO REASON TO MAKE A CHANGE
TO GOING HEADLINES AT THIS POINT. RFW/NPW WILL CONTINUE THROUGH 01Z.
TONIGHT-WEDNESDAY...WINDS WILL QUICKLY DECREASE WITH LOSS OF DAYTIME
MIXING AND WEAKENING GRADIENT THIS EVENING. HIGH CLOUD COVER MOVING
IN FROM THE WEST LATER THIS EVENING MAY LIMIT RADIATIONAL COOLING
TONIGHT AND DIURNAL HEATING WEDNESDAY. LEE TROUGH ALSO REDEVELOPS
AFTER MIDNIGHT TONIGHT IN RESPONSE TO STRONG TROUGH MOVING OUT OF
THE PACIFIC NORTHWEST...WITH RESULTING SOUTHERLY FLOW SUPPORTING WAA
ACROSS THE WEST. I BUMPED LOW TEMPS UP TONIGHT AND HIGH TEMPS UP WED
FOR NOW...AND COULD SEE BOTH PERIODS BEING A LITTLE WARMER/COOLER
THAN ADVERTISED DEPENDING ON CLOUDS. OTHER IMMEDIATE CONCERN WILL BE
BREEZY-WINDY CONDITIONS WEDNESDAY AS SOUTHERLY GRADIENT INCREASE
AHEAD OF APPROACHING UPPER LEVEL SYSTEM. MODEL TEMPERATURE PROFILES
INDICATE MIXING HEIGHTS AROUND 750MB-800MB WHICH KEEPS WINDS JUST
UNDER (OR NEAR) ADVISORY CRITERIA...AND WITH CLOUD COVER POSSIBLY
LIMITING MIXING OVERALL...I DECIDED AGAINST ISSUANCE OF ANOTHER
ADVISORY WED AFTERNOON. UPPER LEVEL SYSTEM DOES APPROACH CENTRAL
ROCKIES WED AFTERNOON AND SURFACE TROUGH WILL SHIFT EAST ALLOWING
WINDS TO DECREASE LATER IN THE AFTERNOON. WHILE FORCING DOES BEGIN
TO INCREASE OVER THE ROCKIES...IT CURRENTLY LOOKS LIKE PRECIP
CHANCES SHOULD HOLD OFF UNTIL WED EVENING.
.LONG TERM...(SATURDAY THROUGH NEXT WEDNESDAY)
ISSUED AT 1211 AM MST WED FEB 19 2014
A TROUGH WILL BE LOCATED OVER THE NORTHERN PLAINS THROUGH MOST OF
THE LONG TERM PERIOD WITH A SERIES OF SHORTWAVE TROUGHS ROTATING
THROUGH. AS A RESULT...TEMPERATURES WILL BE BELOW NORMAL WITH
OCCASIONAL CHANCES OF MAINLY LIGHT WINTRY PRECIPITATION. NONE OF
THESE SYSTEMS APPEAR TO HAVE ENOUGH UPPER SUPPORT FOR MORE THAN AN
INCH OR SO OF SNOW. SOME MIXED PRECIPITATION WILL BE POSSIBLE ON
SATURDAY WITH TEMPERATURES NEAR OR SLIGHTLY ABOVE FREEZING. A
FAIRLY STRONG COLD FRONT WILL MOVE THROUGH ON MONDAY WITH GUSTY
NORTH WINDS AND COLDEST TEMPERATURES OF THE PERIOD. HOWEVER...THE
COLDEST AIR WILL REMAIN IN THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1030 PM MST TUE FEB 18 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH CEILINGS
LOWERING NEAR THE END OR AFTER THE TAF PERIOD BEHIND THE NEXT COLD
FRONT. CURRENTLY...SURFACE HIGH PRESSURE OVER THE REGION IS ALLOWING
WINDS TO REMAIN LIGHT AND VARIABLE TO CALM. WINDS WILL BECOME
SOUTHERLY AS THE SURFACE HIGH DEPARTS AND A LEE SIDE SURFACE LOW
DEVELOPS OVER EASTERN COLORADO. SOUTHERLY WINDS WILL BECOME BREEZY
AT 16 KTS WITH GUSTS AROUND 20 TO 25 KTS FOR BOTH SITES. KGLD COULD
SEE HIGHER GUSTS AROUND 31 KTS AROUND 18Z. THE COLD FRONT WILL MOVE
THROUGH KGLD FIRST AROUND 04Z...WITH WINDS SHIFTING TO THE NORTHEAST
AND EVENTUALLY NORTH GUSTING TO AROUND 25 KTS. NAM BUFKIT SOUNDINGS
INDICATE THAT THERE WILL BE A CHANCE FOR LIGHT RAIN AT KGLD AT
04Z...BUT SINCE EXACT TIMING OF SHOWERS MOVING OVER THE TERMINAL IS
HARD TO PIN DOWN THIS FAR OUT...WENT WITH VCSH. KMCK SHOULD SEE
AFTERNOON GUSTS DIMINISH AROUND 0Z WITH SOUTHEAST WINDS...BUT THE
COLD FRONT SHOULD MOVE THROUGH KGLD FIRST SO DID NOT THINK VCSH
WOULD BE NEAR KMCK BEFORE THE END OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ THIS EVENING TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-027.
WINTER WEATHER ADVISORY FROM 10 PM MST /11 PM CST/ THIS EVENING
TO 6 AM MST /7 AM CST/ THURSDAY FOR KSZ003-004-014>016-028-
029-041-042.
CO...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 6 AM MST
THURSDAY FOR COZ090>092.
NE...WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ THIS EVENING TO
6 AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
&&
$$
UPDATE...RRH
SHORT TERM...DJR
LONG TERM...024
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1030 PM MST TUE FEB 18 2014
.UPDATE...
ISSUED AT 948 PM MST TUE FEB 18 2014
UPDATED THE FORECAST FOR LATEST THINKING ON THE UPCOMING WIND AND
SNOW EVENT TOMORROW NIGHT. MAINTAINED/REFRESHED THE WSW...HWO AND
ZFP BY UPDATING THE TIMING OF THE RAIN/SNOW TRANSITION AND THE
ARRIVAL OF STRONGEST WINDS/ASSOCIATED BLOWING SNOW THREAT.
PRESSURE RISES BEHIND THE COLD FRONT WEDNESDAY EVENING/NIGHT ARE
VERY IMPRESSIVE...ON THE ORDER OF 12-16 MB OVER 3-6 HOURS. THIS ONLY
INCREASES CONFIDENCE IN PROBLEMS WITH STRONG WINDS TOMORROW NIGHT. MODELS
BRING PRECIPITATION INTO THE AREA BEHIND THE FRONT WITHOUT MUCH
AHEAD OF IT. THIS IS DUE TO SOME DRY AIR AT THE LOW LEVELS AND
ALOFT WITH A DRY AIR INTRUSION. BEHIND THE FRONT...THE ATMOSPHERIC
PROFILE SATURATES AND PRECIPITATION WILL BEGIN TO REACH THE
GROUND. IT SEEMS THERE WILL BE A STRONG BAND OF SNOW THAT WILL
DEVELOP BEHIND THE FRONT AND TRANSITION ACROSS THE AREA FAIRLY
QUICKLY. UNDER THE BAND...SNOWFALL RATES AND WINDS WILL BRING
PROBLEMS WITH BLOWING SNOW AND DRIFTING. VISIBILITIES WILL BE NEAR
ZERO AT TIMES. DUE TO THE QUICK MOVEMENT OF THE BAND...SNOWFALL
AMOUNTS ARE NOT EXPECTED TO BE NEARLY AS HIGH AS RECENT BANDED
SNOWFALL EVENTS. AT THIS POINT...ONE TO THREE INCHES OF SNOW IS
EXPECTED WITH THE POTENTIAL TO SEE CLOSER TO 4 INCHES OVER
SOUTHWEST NEBRASKA. VERY COMPLICATED SCENARIO AS THE WINDS MAY
APPROACH HIGH WIND WARNING CRITERIA BUT BLIZZARD CONDITIONS MAY
NOT BE MET FOR THE FULL THREE HOUR REQUIREMENT. THEREFORE...THE
ADVISORY WAS ISSUED AS WINTER STORM CRITERIA WOULD NOT BE MET AS
WELL. HIGHLIGHT CHANGES MAY BE NEEDED CLOSER TO THE EVENT
DEPENDING ON DURATION OF HEAVIER SNOW AND THUS LOWER VISIBILITIES
OR THE STRENGTH OF THE WINDS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 145 PM MST TUE FEB 18 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS INDICATE SHORTWAVE TROUGH OVER
EASTERN NEBRASKA/KANSAS WITH SHORTWAVE RIDGE OVER THE GREAT BASIN
AND NORTHERN ROCKIES. A COLD FRONT (WHICH SHOWS UP BETTER WITH
VERTICAL THICKNESS FIELD) IS MOVING SOUTH TO THE KS/NE BORDER WITH A
PREFRONTAL SURFACE TROUGH AXIS NOW ACROSS CENTRAL KANSAS.
THIS AFTERNOON...STRONG PRESSURE GRADIENT HAS LED TO DEVELOPMENT OF
WIND GUSTS 45-60 MPH ACROSS THE NORTHERN HALF OF THE CWA...WITH
WINDS JUST STARTING TO COME UP ACROSS THE EAST AND SOUTH OVER THE
LAST HOUR. STRONGEST GUSTS WERE ASSOCIATED WITH INITIAL SURGE AS
SURFACE TROUGH SHIFTED SOUTH AND 3HR PRESSURE RISES BEHIND COLD
FRONT PEAKED AROUND 4MB. WINDS HAVE STABILIZED WITHIN ADVISORY
CRITERIA AFTER THIS INITIAL SURGE...SO DECISION WAS MADE TO HOLD
ONTO ADVISORY. RED FLAG CONDITIONS ARE BEING MET AT MOST OF WARNED
AREA...THOUGH INCREASING TD VALUES FROM THE NORTH ARE KEEPING RH
VALUES CLOSER TO 30 PERCENT ACROSS THE NORTHERN PART OF THE RFW. WE
MAY NOT MEET THE HIGH END THRESHOLD FOR RED FLAG CONDITIONS...
HOWEVER WITH THE MAGNITUDE OF WIND...I SEE NO REASON TO MAKE A CHANGE
TO GOING HEADLINES AT THIS POINT. RFW/NPW WILL CONTINUE THROUGH 01Z.
TONIGHT-WEDNESDAY...WINDS WILL QUICKLY DECREASE WITH LOSS OF DAYTIME
MIXING AND WEAKENING GRADIENT THIS EVENING. HIGH CLOUD COVER MOVING
IN FROM THE WEST LATER THIS EVENING MAY LIMIT RADIATIONAL COOLING
TONIGHT AND DIURNAL HEATING WEDNESDAY. LEE TROUGH ALSO REDEVELOPS
AFTER MIDNIGHT TONIGHT IN RESPONSE TO STRONG TROUGH MOVING OUT OF
THE PACIFIC NORTHWEST...WITH RESULTING SOUTHERLY FLOW SUPPORTING WAA
ACROSS THE WEST. I BUMPED LOW TEMPS UP TONIGHT AND HIGH TEMPS UP WED
FOR NOW...AND COULD SEE BOTH PERIODS BEING A LITTLE WARMER/COOLER
THAN ADVERTISED DEPENDING ON CLOUDS. OTHER IMMEDIATE CONCERN WILL BE
BREEZY-WINDY CONDITIONS WEDNESDAY AS SOUTHERLY GRADIENT INCREASE
AHEAD OF APPROACHING UPPER LEVEL SYSTEM. MODEL TEMPERATURE PROFILES
INDICATE MIXING HEIGHTS AROUND 750MB-800MB WHICH KEEPS WINDS JUST
UNDER (OR NEAR) ADVISORY CRITERIA...AND WITH CLOUD COVER POSSIBLY
LIMITING MIXING OVERALL...I DECIDED AGAINST ISSUANCE OF ANOTHER
ADVISORY WED AFTERNOON. UPPER LEVEL SYSTEM DOES APPROACH CENTRAL
ROCKIES WED AFTERNOON AND SURFACE TROUGH WILL SHIFT EAST ALLOWING
WINDS TO DECREASE LATER IN THE AFTERNOON. WHILE FORCING DOES BEGIN
TO INCREASE OVER THE ROCKIES...IT CURRENTLY LOOKS LIKE PRECIP
CHANCES SHOULD HOLD OFF UNTIL WED EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 PM MST TUE FEB 18 2014
FORECAST CONCERNS WILL BE WINDS THROUGH FRIDAY AND PRECIPITATION
CHANCE/PHASE WEDNESDAY NIGHT. SATELLITE SHOWING A PROGRESSIVE AND
ACTIVE WAVE TRAIN FROM THE PACIFIC INTO THE ATLANTIC. NEXT SHORTWAVE
OF INTEREST IS ENTERING THE PACIFIC NORTHWEST. VERY DRY AIR MASS
ALOFT AT THIS TIME.
AT JET LEVEL...MODELS STARTED OUT FINE. AT MID LEVELS...LOOKS TO BE
NO SERIOUS INITIALIZATION PROBLEMS WITH THE MODELS MAYBE A LITTLE
TOO FAR SOUTH AND EAST. AT THIS TIME...THE ECMWF...CANADIAN...UKMET
AND GFS APPEAR TO BE DOING SLIGHTLY BETTER. ECMWF AND SREF WERE
DOING WELL INITIALLY WITH THE SURFACE WIND AND PRESSURE PATTERN.
THE CANADIAN...UKMET AND GFS WERE DOING THE BEST WITH THE LOW LEVEL
THERMAL FIELD.
WEDNESDAY NIGHT...AREA TRANSITIONS FROM WARM...DRY AND WINDY TO
COLD...WET AND WINDY. THERE ARE SOME DIFFERENCES IN THE JET AND
TROUGH POSITION. SOME MODELS HAVE THE LEFT FRONT QUADRANT WELL
SOUTH...AFFECTING THE SOUTHERN HALF OF THE AREA OR STILL TO THE WEST
OF THE AREA. BY THE MIDDLE OF THE NIGHT...THE JET AXIS HAS MOVED
ACROSS WITH THE MAIN AFFECT FROM THE LEFT FRONT QUADRANT ACROSS THE
SOUTHERN HALF OF THE AREA THROUGH THE EVENING. VERY STRONG
FRONTOGENETICAL FORCING MOVES ACROSS THE AREA FROM EARLY IN THE
EVENING TO LATE IN THE NIGHT. THETA-E LAPSE RATES NEAR ZERO OR
SLIGHTLY BELOW ZERO ARE NOT ONLY AT MID LEVELS FOR THE ENTIRE NIGHT
BUT FOR A BRIEF PERIOD ARE AT LOW LEVELS.
SO THE LIKELIHOOD OF PRECIPITATION IS PRETTY HIGH. THE QUESTION
BECOMES WHEN WILL THE PHASE CHANGE FROM RAIN TO SNOW AND HOW MUCH
SNOW WILL OCCUR AFTER THIS HAPPENS. MODEL SOUNDINGS AND WET BULB
PROGS WOULD INDICATE THE NORTHWEST HALF WILL TRANSITION FROM A
RAIN/SNOW MIX EARLY TO ALL SNOW BY 06Z. THE SOUTHEAST HALF WILL
HAVE RAIN UNTIL NEAR 05-06Z BEFORE RAPIDLY CHANGING TO SNOW.
PRECIPITABLE WATER NEARS A HALF INCH OVER THE EASTERN HALF TO TWO
THIRDS OF THE AREA. LIKE THE REPRESENTATION OF QPF THAT WPC HAS AND
USED AS A THE BUILDING BLOCK FOR THE QPF AND SNOWFALL. WPC SLR
GUIDANCE WOULD INDICATE A NEAR 13 TO 1 RATIO IS NEAR NORMAL AND THAT
SEEMS REASONABLE. SO CONSIDERING THE FORCING AND INSTABILITY...THE
SNOW COULD BE RATHER INTENSE AT TIMES DURING THE NIGHT.
SO WITH USING THE WPC QPF AND CUTTING OFF A LITTLE BIT DUE TO THE
EXPECTED PHASE TO BE RAIN...CAME UP WITH 1 TO 4 INCHES WITH THE
LOWEST IN THE FAR SOUTH AND THE MOST FROM YUMA COUNTY TO THE COUNTIES
ALONG THE KANSAS AND NEBRASKA BORDER.
ALL INDICATIONS ARE THAT VERY WINDY CONDITIONS WILL BE A CERTAINTY.
EXTREMELY TIGHT PRESSURE GRADIENT AND 3 HOUR PRESSURE RISES OF NEAR
10 MB WILL PRODUCE VERY WINDY CONDITIONS. AND THAT IS NOT EVEN
CONSIDERING THE POSSIBILITY OF MIXING DOWN EVEN STRONGER WINDS.
THOUGHT LONG AND HARD ABOUT HOW TO HANDLE THIS SCENARIO. WINDS
SHOULD BE IN THE HIGH WIND ADVISORY TO LOW HIGH WIND WARNING RANGE.
SO DESPITE THE AMOUNT OF SNOW EXPECTED...SIGNIFICANT BLOWING OF THAT
SNOW IS EXPECTED. DUE TO HOW FAST THE SNOW MOVES ACROSS THE AREA...3
HOURS OF BLIZZARD CONDITIONS ARE NOT EXPECTED TO OCCUR WHICH WOULD
MEAN A BLIZZARD WARNING. AFTER PLENTY OF DISCUSSION WE HAVE DECIDED
TO ISSUE A WINTER WEATHER ADVISORY AND EMPHASIZE THAT NEAR BLIZZARD
OR BLIZZARD CONDITIONS COULD OCCUR FOR A SHORT PERIOD OF TIME WITH
VISIBILITIES OF A HALF MILE TO A MILE EXPECTED FOR MOST OF THE
PERIOD. SNOW SHOULD BE DONE BY THE END OF THE NIGHT PLUS THE WINDS
SHOULD GO DOWN BY THAT TIME. SO THE WINTER WEATHER ADVISORY WILL BE
FOR THE WHOLE NIGHT FOR THE NORTHWEST HALF AND FOR THE SOUTHEAST HALF
FOR THE LAST HALF OF THE NIGHT ENDING AT 6 TO 7 AM LOCAL TIME.
THURSDAY/THURSDAY NIGHT...SOME DIFFERENCES IN THE SPEED OF INCOMING
NORTH TO SOUTH JET...BUT IT LOOKS TO BE WEST OF THE AREA THROUGH
THE DAY. THAT SEGMENT FLATTENS OUT WITH A WEST TO EAST JET AXIS AND
RIGHT REAR QUADRANT OVER THE NORTHERN HALF OF THE AREA BY THE END
OF THE NIGHT. AT THIS TIME ALL THE MOISTURE IS ALOFT SO THIS WILL
ONLY CAUSE CLOUDS.
THE BIG PROBLEM WILL BE THAT WINDS WILL COME UP AGAIN DURING THE
DAY BEHIND THE EXITING SHORTWAVE TROUGH. QUESTIONS WILL BE HOW
MUCH MIXING WILL OCCUR...ESPECIALLY IN THE NORTH...DUE TO SNOW ON THE
GROUND. LOOK TO STAY MIXED THROUGH THE NIGHT. DURING THE DAY THERE IS
GOOD UNIDIRECTIONAL FLOW WITH DECENT DOWNWARD MOTION. MODELS SHOW
GOOD LAPSE RATES TO AT LEAST 700 MB. SO IT WOULD APPEAR THINGS WILL
MIX WELL. MODEL SOUNDINGS WOULD INDICATE AT LEAST WIND ADVISORY...
POSSIBLY HIGH END...AND POSSIBLY REACHING HIGH WIND WARNING
CRITERIA. SO WILL KEEP WINDY TO VERY WINDY CONDITIONS AND THIS WILL
NEED TO BE ADDRESSED AFTER THE WINTER WEATHER ADVISORY IS DONE.
DEPENDING ON THE AMOUNT OF SNOW AND HOW MUCH IF ANY THE SNOW CRUSTS
OVER...THERE COULD BE SOME MORE BLOWING SNOW DESPITE NO PRECIPITATION
OCCURRING. SO DID PUT IN PATCHY BLOWING SNOW AT THIS TIME. WILL PUT
MAXES IN NEAR TO SLIGHTLY BELOW GUIDANCE.
FRIDAY...ABOVE JET MOVES SOUTH ACROSS THE AREA AT VARIOUS SPEEDS AND
WILL BE NEAR OR JUST SOUTH OF THE AREA BY THE END OF THE DAY. THIS
JUST LOOKS TO PRODUCE SOME CLOUDS. MODELS SHOWING WIND SPEEDS
INCREASING INTO THE WINDY CATEGORY AGAIN. LAPSE RATES LOOK TO STILL
STAY GOOD BUT THE FLOW IS NOT AS UNIDIRECTIONAL AND THE DOWNWARD
MOTION IS NOT AS GREAT. BUFKIT SOUNDINGS ARE INDICATING THE MIXING
DOWN OF A LEAST WIND ADVISORY CRITERIA WINDS AGAIN. WILL DEFINITELY
TRY AND HAVE WINDY WORDING IN THERE AT THIS TIME. TEMPERATURES
SHOULD BE WARMER BUT NOT SURE DEPENDING ON THE AMOUNT OF SNOW ON THE
GROUND.
FRIDAY NIGHT THROUGH TUESDAY...AT END OF THE SHORT TERM INTO THE
BEGINNING OF THIS PERIOD...THE PATTERN TRANSITIONS FROM A
PROGRESSIVE FLOW TO A HIGH AMPLITUDE RIDGE ALONG THE WEST COAST OF
NORTH AMERICA AND HUDSON BAY LOW BECOMING ESTABLISHED ONCE AGAIN BY
THE END OF THE PERIOD. PRECIPITATION IS VERY HARD TO PIN DOWN. WILL
HAVE VERY FAST WEST TO NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
AND JET ENERGY. SIGNIFICANT MOISTURE WILL BE HARD TO COME BY IN THIS
SCENARIO. HOWEVER CANNOT RULE OUT SOME BRIEF AND SPOTTY PRECIPITATION
CHANCES. SO LEFT THE CRH_INIT POPS ALONE WHICH WERE NO HIGHER THAN
SLIGHT CHANCE WHICH SEEMS REASONABLE.
COLDER TEMPERATURES LOOK TO BE COMING BACK. BY LATE IN THE WEEKEND
A SHALLOW COLD AIR MASS WILL BE IN PLACE AS A SURFACE RIDGE BECOMES
ESTABLISHED OVER THE NORTH CENTRAL PORTION OF THE COUNTRY. SO
FOLLOWED OTHER OFFICES AND MADE SLIGHT ADJUSTMENTS DOWN IN
TEMPERATURES...ESPECIALLY THE MAXES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1030 PM MST TUE FEB 18 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH CEILINGS
LOWERING NEAR THE END OR AFTER THE TAF PERIOD BEHIND THE NEXT COLD
FRONT. CURRENTLY...SURFACE HIGH PRESSURE OVER THE REGION IS ALLOWING
WINDS TO REMAIN LIGHT AND VARIABLE TO CALM. WINDS WILL BECOME
SOUTHERLY AS THE SURFACE HIGH DEPARTS AND A LEE SIDE SURFACE LOW
DEVELOPS OVER EASTERN COLORADO. SOUTHERLY WINDS WILL BECOME BREEZY
AT 16 KTS WITH GUSTS AROUND 20 TO 25 KTS FOR BOTH SITES. KGLD COULD
SEE HIGHER GUSTS AROUND 31 KTS AROUND 18Z. THE COLD FRONT WILL MOVE
THROUGH KGLD FIRST AROUND 04Z...WITH WINDS SHIFTING TO THE NORTHEAST
AND EVENTUALLY NORTH GUSTING TO AROUND 25 KTS. NAM BUFKIT SOUNDINGS
INDICATE THAT THERE WILL BE A CHANCE FOR LIGHT RAIN AT KGLD AT
04Z...BUT SINCE EXACT TIMING OF SHOWERS MOVING OVER THE TERMINAL IS
HARD TO PIN DOWN THIS FAR OUT...WENT WITH VCSH. KMCK SHOULD SEE
AFTERNOON GUSTS DIMINISH AROUND 0Z WITH SOUTHEAST WINDS...BUT THE
COLD FRONT SHOULD MOVE THROUGH KGLD FIRST SO DID NOT THINK VCSH
WOULD BE NEAR KMCK BEFORE THE END OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-027.
WINTER WEATHER ADVISORY FROM 10 PM MST /11 PM CST/ WEDNESDAY TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ003-004-014>016-028-029-
041-042.
CO...WINTER WEATHER ADVISORY FROM 7 PM WEDNESDAY TO 6 AM MST THURSDAY
FOR COZ090>092.
NE...WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
&&
$$
UPDATE...RRH
SHORT TERM...DJR
LONG TERM...BULLER
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
948 PM MST TUE FEB 18 2014
.UPDATE...
ISSUED AT 948 PM MST TUE FEB 18 2014
UPDATED THE FORECAST FOR LATEST THINKING ON THE UPCOMING WIND AND
SNOW EVENT TOMORROW NIGHT. MAINTAINED/REFRESHED THE WSW...HWO AND
ZFP BY UPDATING THE TIMING OF THE RAIN/SNOW TRANSITION AND THE
ARRIVAL OF STRONGEST WINDS/ASSOCIATED BLOWING SNOW THREAT.
PRESSURE RISES BEHIND THE COLD FRONT WEDNESDAY EVENING/NIGHT ARE
VERY IMPRESSIVE...ON THE ORDER OF 12-16 MB OVER 3-6 HOURS. THIS ONLY
INCREASES CONFIDENCE IN PROBLEMS WITH STRONG WINDS TOMORROW NIGHT. MODELS
BRING PRECIPITATION INTO THE AREA BEHIND THE FRONT WITHOUT MUCH
AHEAD OF IT. THIS IS DUE TO SOME DRY AIR AT THE LOW LEVELS AND
ALOFT WITH A DRY AIR INTRUSION. BEHIND THE FRONT...THE ATMOSPHERIC
PROFILE SATURATES AND PRECIPITATION WILL BEGIN TO REACH THE
GROUND. IT SEEMS THERE WILL BE A STRONG BAND OF SNOW THAT WILL
DEVELOP BEHIND THE FRONT AND TRANSITION ACROSS THE AREA FAIRLY
QUICKLY. UNDER THE BAND...SNOWFALL RATES AND WINDS WILL BRING
PROBLEMS WITH BLOWING SNOW AND DRIFTING. VISIBILITIES WILL BE NEAR
ZERO AT TIMES. DUE TO THE QUICK MOVEMENT OF THE BAND...SNOWFALL
AMOUNTS ARE NOT EXPECTED TO BE NEARLY AS HIGH AS RECENT BANDED
SNOWFALL EVENTS. AT THIS POINT...ONE TO THREE INCHES OF SNOW IS
EXPECTED WITH THE POTENTIAL TO SEE CLOSER TO 4 INCHES OVER
SOUTHWEST NEBRASKA. VERY COMPLICATED SCENARIO AS THE WINDS MAY
APPROACH HIGH WIND WARNING CRITERIA BUT BLIZZARD CONDITIONS MAY
NOT BE MET FOR THE FULL THREE HOUR REQUIREMENT. THEREFORE...THE
ADVISORY WAS ISSUED AS WINTER STORM CRITERIA WOULD NOT BE MET AS
WELL. HIGHLIGHT CHANGES MAY BE NEEDED CLOSER TO THE EVENT
DEPENDING ON DURATION OF HEAVIER SNOW AND THUS LOWER VISIBILITIES
OR THE STRENGTH OF THE WINDS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 145 PM MST TUE FEB 18 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS INDICATE SHORTWAVE TROUGH OVER
EASTERN NEBRASKA/KANSAS WITH SHORTWAVE RIDGE OVER THE GREAT BASIN
AND NORTHERN ROCKIES. A COLD FRONT (WHICH SHOWS UP BETTER WITH
VERTICAL THICKNESS FIELD) IS MOVING SOUTH TO THE KS/NE BORDER WITH A
PREFRONTAL SURFACE TROUGH AXIS NOW ACROSS CENTRAL KANSAS.
THIS AFTERNOON...STRONG PRESSURE GRADIENT HAS LED TO DEVELOPMENT OF
WIND GUSTS 45-60 MPH ACROSS THE NORTHERN HALF OF THE CWA...WITH
WINDS JUST STARTING TO COME UP ACROSS THE EAST AND SOUTH OVER THE
LAST HOUR. STRONGEST GUSTS WERE ASSOCIATED WITH INITIAL SURGE AS
SURFACE TROUGH SHIFTED SOUTH AND 3HR PRESSURE RISES BEHIND COLD
FRONT PEAKED AROUND 4MB. WINDS HAVE STABILIZED WITHIN ADVISORY
CRITERIA AFTER THIS INITIAL SURGE...SO DECISION WAS MADE TO HOLD
ONTO ADVISORY. RED FLAG CONDITIONS ARE BEING MET AT MOST OF WARNED
AREA...THOUGH INCREASING TD VALUES FROM THE NORTH ARE KEEPING RH
VALUES CLOSER TO 30 PERCENT ACROSS THE NORTHERN PART OF THE RFW. WE
MAY NOT MEET THE HIGH END THRESHOLD FOR RED FLAG CONDITIONS...
HOWEVER WITH THE MAGNITUDE OF WIND...I SEE NO REASON TO MAKE A CHANGE
TO GOING HEADLINES AT THIS POINT. RFW/NPW WILL CONTINUE THROUGH 01Z.
TONIGHT-WEDNESDAY...WINDS WILL QUICKLY DECREASE WITH LOSS OF DAYTIME
MIXING AND WEAKENING GRADIENT THIS EVENING. HIGH CLOUD COVER MOVING
IN FROM THE WEST LATER THIS EVENING MAY LIMIT RADIATIONAL COOLING
TONIGHT AND DIURNAL HEATING WEDNESDAY. LEE TROUGH ALSO REDEVELOPS
AFTER MIDNIGHT TONIGHT IN RESPONSE TO STRONG TROUGH MOVING OUT OF
THE PACIFIC NORTHWEST...WITH RESULTING SOUTHERLY FLOW SUPPORTING WAA
ACROSS THE WEST. I BUMPED LOW TEMPS UP TONIGHT AND HIGH TEMPS UP WED
FOR NOW...AND COULD SEE BOTH PERIODS BEING A LITTLE WARMER/COOLER
THAN ADVERTISED DEPENDING ON CLOUDS. OTHER IMMEDIATE CONCERN WILL BE
BREEZY-WINDY CONDITIONS WEDNESDAY AS SOUTHERLY GRADIENT INCREASE
AHEAD OF APPROACHING UPPER LEVEL SYSTEM. MODEL TEMPERATURE PROFILES
INDICATE MIXING HEIGHTS AROUND 750MB-800MB WHICH KEEPS WINDS JUST
UNDER (OR NEAR) ADVISORY CRITERIA...AND WITH CLOUD COVER POSSIBLY
LIMITING MIXING OVERALL...I DECIDED AGAINST ISSUANCE OF ANOTHER
ADVISORY WED AFTERNOON. UPPER LEVEL SYSTEM DOES APPROACH CENTRAL
ROCKIES WED AFTERNOON AND SURFACE TROUGH WILL SHIFT EAST ALLOWING
WINDS TO DECREASE LATER IN THE AFTERNOON. WHILE FORCING DOES BEGIN
TO INCREASE OVER THE ROCKIES...IT CURRENTLY LOOKS LIKE PRECIP
CHANCES SHOULD HOLD OFF UNTIL WED EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 PM MST TUE FEB 18 2014
FORECAST CONCERNS WILL BE WINDS THROUGH FRIDAY AND PRECIPITATION
CHANCE/PHASE WEDNESDAY NIGHT. SATELLITE SHOWING A PROGRESSIVE AND
ACTIVE WAVE TRAIN FROM THE PACIFIC INTO THE ATLANTIC. NEXT SHORTWAVE
OF INTEREST IS ENTERING THE PACIFIC NORTHWEST. VERY DRY AIR MASS
ALOFT AT THIS TIME.
AT JET LEVEL...MODELS STARTED OUT FINE. AT MID LEVELS...LOOKS TO BE
NO SERIOUS INITIALIZATION PROBLEMS WITH THE MODELS MAYBE A LITTLE
TOO FAR SOUTH AND EAST. AT THIS TIME...THE ECMWF...CANADIAN...UKMET
AND GFS APPEAR TO BE DOING SLIGHTLY BETTER. ECMWF AND SREF WERE
DOING WELL INITIALLY WITH THE SURFACE WIND AND PRESSURE PATTERN.
THE CANADIAN...UKMET AND GFS WERE DOING THE BEST WITH THE LOW LEVEL
THERMAL FIELD.
WEDNESDAY NIGHT...AREA TRANSITIONS FROM WARM...DRY AND WINDY TO
COLD...WET AND WINDY. THERE ARE SOME DIFFERENCES IN THE JET AND
TROUGH POSITION. SOME MODELS HAVE THE LEFT FRONT QUADRANT WELL
SOUTH...AFFECTING THE SOUTHERN HALF OF THE AREA OR STILL TO THE WEST
OF THE AREA. BY THE MIDDLE OF THE NIGHT...THE JET AXIS HAS MOVED
ACROSS WITH THE MAIN AFFECT FROM THE LEFT FRONT QUADRANT ACROSS THE
SOUTHERN HALF OF THE AREA THROUGH THE EVENING. VERY STRONG
FRONTOGENETICAL FORCING MOVES ACROSS THE AREA FROM EARLY IN THE
EVENING TO LATE IN THE NIGHT. THETA-E LAPSE RATES NEAR ZERO OR
SLIGHTLY BELOW ZERO ARE NOT ONLY AT MID LEVELS FOR THE ENTIRE NIGHT
BUT FOR A BRIEF PERIOD ARE AT LOW LEVELS.
SO THE LIKELIHOOD OF PRECIPITATION IS PRETTY HIGH. THE QUESTION
BECOMES WHEN WILL THE PHASE CHANGE FROM RAIN TO SNOW AND HOW MUCH
SNOW WILL OCCUR AFTER THIS HAPPENS. MODEL SOUNDINGS AND WET BULB
PROGS WOULD INDICATE THE NORTHWEST HALF WILL TRANSITION FROM A
RAIN/SNOW MIX EARLY TO ALL SNOW BY 06Z. THE SOUTHEAST HALF WILL
HAVE RAIN UNTIL NEAR 05-06Z BEFORE RAPIDLY CHANGING TO SNOW.
PRECIPITABLE WATER NEARS A HALF INCH OVER THE EASTERN HALF TO TWO
THIRDS OF THE AREA. LIKE THE REPRESENTATION OF QPF THAT WPC HAS AND
USED AS A THE BUILDING BLOCK FOR THE QPF AND SNOWFALL. WPC SLR
GUIDANCE WOULD INDICATE A NEAR 13 TO 1 RATIO IS NEAR NORMAL AND THAT
SEEMS REASONABLE. SO CONSIDERING THE FORCING AND INSTABILITY...THE
SNOW COULD BE RATHER INTENSE AT TIMES DURING THE NIGHT.
SO WITH USING THE WPC QPF AND CUTTING OFF A LITTLE BIT DUE TO THE
EXPECTED PHASE TO BE RAIN...CAME UP WITH 1 TO 4 INCHES WITH THE
LOWEST IN THE FAR SOUTH AND THE MOST FROM YUMA COUNTY TO THE COUNTIES
ALONG THE KANSAS AND NEBRASKA BORDER.
ALL INDICATIONS ARE THAT VERY WINDY CONDITIONS WILL BE A CERTAINTY.
EXTREMELY TIGHT PRESSURE GRADIENT AND 3 HOUR PRESSURE RISES OF NEAR
10 MB WILL PRODUCE VERY WINDY CONDITIONS. AND THAT IS NOT EVEN
CONSIDERING THE POSSIBILITY OF MIXING DOWN EVEN STRONGER WINDS.
THOUGHT LONG AND HARD ABOUT HOW TO HANDLE THIS SCENARIO. WINDS
SHOULD BE IN THE HIGH WIND ADVISORY TO LOW HIGH WIND WARNING RANGE.
SO DESPITE THE AMOUNT OF SNOW EXPECTED...SIGNIFICANT BLOWING OF THAT
SNOW IS EXPECTED. DUE TO HOW FAST THE SNOW MOVES ACROSS THE AREA...3
HOURS OF BLIZZARD CONDITIONS ARE NOT EXPECTED TO OCCUR WHICH WOULD
MEAN A BLIZZARD WARNING. AFTER PLENTY OF DISCUSSION WE HAVE DECIDED
TO ISSUE A WINTER WEATHER ADVISORY AND EMPHASIZE THAT NEAR BLIZZARD
OR BLIZZARD CONDITIONS COULD OCCUR FOR A SHORT PERIOD OF TIME WITH
VISIBILITIES OF A HALF MILE TO A MILE EXPECTED FOR MOST OF THE
PERIOD. SNOW SHOULD BE DONE BY THE END OF THE NIGHT PLUS THE WINDS
SHOULD GO DOWN BY THAT TIME. SO THE WINTER WEATHER ADVISORY WILL BE
FOR THE WHOLE NIGHT FOR THE NORTHWEST HALF AND FOR THE SOUTHEAST HALF
FOR THE LAST HALF OF THE NIGHT ENDING AT 6 TO 7 AM LOCAL TIME.
THURSDAY/THURSDAY NIGHT...SOME DIFFERENCES IN THE SPEED OF INCOMING
NORTH TO SOUTH JET...BUT IT LOOKS TO BE WEST OF THE AREA THROUGH
THE DAY. THAT SEGMENT FLATTENS OUT WITH A WEST TO EAST JET AXIS AND
RIGHT REAR QUADRANT OVER THE NORTHERN HALF OF THE AREA BY THE END
OF THE NIGHT. AT THIS TIME ALL THE MOISTURE IS ALOFT SO THIS WILL
ONLY CAUSE CLOUDS.
THE BIG PROBLEM WILL BE THAT WINDS WILL COME UP AGAIN DURING THE
DAY BEHIND THE EXITING SHORTWAVE TROUGH. QUESTIONS WILL BE HOW
MUCH MIXING WILL OCCUR...ESPECIALLY IN THE NORTH...DUE TO SNOW ON THE
GROUND. LOOK TO STAY MIXED THROUGH THE NIGHT. DURING THE DAY THERE IS
GOOD UNIDIRECTIONAL FLOW WITH DECENT DOWNWARD MOTION. MODELS SHOW
GOOD LAPSE RATES TO AT LEAST 700 MB. SO IT WOULD APPEAR THINGS WILL
MIX WELL. MODEL SOUNDINGS WOULD INDICATE AT LEAST WIND ADVISORY...
POSSIBLY HIGH END...AND POSSIBLY REACHING HIGH WIND WARNING
CRITERIA. SO WILL KEEP WINDY TO VERY WINDY CONDITIONS AND THIS WILL
NEED TO BE ADDRESSED AFTER THE WINTER WEATHER ADVISORY IS DONE.
DEPENDING ON THE AMOUNT OF SNOW AND HOW MUCH IF ANY THE SNOW CRUSTS
OVER...THERE COULD BE SOME MORE BLOWING SNOW DESPITE NO PRECIPITATION
OCCURRING. SO DID PUT IN PATCHY BLOWING SNOW AT THIS TIME. WILL PUT
MAXES IN NEAR TO SLIGHTLY BELOW GUIDANCE.
FRIDAY...ABOVE JET MOVES SOUTH ACROSS THE AREA AT VARIOUS SPEEDS AND
WILL BE NEAR OR JUST SOUTH OF THE AREA BY THE END OF THE DAY. THIS
JUST LOOKS TO PRODUCE SOME CLOUDS. MODELS SHOWING WIND SPEEDS
INCREASING INTO THE WINDY CATEGORY AGAIN. LAPSE RATES LOOK TO STILL
STAY GOOD BUT THE FLOW IS NOT AS UNIDIRECTIONAL AND THE DOWNWARD
MOTION IS NOT AS GREAT. BUFKIT SOUNDINGS ARE INDICATING THE MIXING
DOWN OF A LEAST WIND ADVISORY CRITERIA WINDS AGAIN. WILL DEFINITELY
TRY AND HAVE WINDY WORDING IN THERE AT THIS TIME. TEMPERATURES
SHOULD BE WARMER BUT NOT SURE DEPENDING ON THE AMOUNT OF SNOW ON THE
GROUND.
FRIDAY NIGHT THROUGH TUESDAY...AT END OF THE SHORT TERM INTO THE
BEGINNING OF THIS PERIOD...THE PATTERN TRANSITIONS FROM A
PROGRESSIVE FLOW TO A HIGH AMPLITUDE RIDGE ALONG THE WEST COAST OF
NORTH AMERICA AND HUDSON BAY LOW BECOMING ESTABLISHED ONCE AGAIN BY
THE END OF THE PERIOD. PRECIPITATION IS VERY HARD TO PIN DOWN. WILL
HAVE VERY FAST WEST TO NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
AND JET ENERGY. SIGNIFICANT MOISTURE WILL BE HARD TO COME BY IN THIS
SCENARIO. HOWEVER CANNOT RULE OUT SOME BRIEF AND SPOTTY PRECIPITATION
CHANCES. SO LEFT THE CRH_INIT POPS ALONE WHICH WERE NO HIGHER THAN
SLIGHT CHANCE WHICH SEEMS REASONABLE.
COLDER TEMPERATURES LOOK TO BE COMING BACK. BY LATE IN THE WEEKEND
A SHALLOW COLD AIR MASS WILL BE IN PLACE AS A SURFACE RIDGE BECOMES
ESTABLISHED OVER THE NORTH CENTRAL PORTION OF THE COUNTRY. SO
FOLLOWED OTHER OFFICES AND MADE SLIGHT ADJUSTMENTS DOWN IN
TEMPERATURES...ESPECIALLY THE MAXES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 412 PM MST TUE FEB 18 2014
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD. SURFACE HIGH
PRESSURE WILL SETTLE IN OVER BOTH TERMINALS TONIGHT...ALLOWING
WINDS TO BECOME LIGHT AND VARIABLE. AS THE SURFACE HIGH MOVES
EAST...SOUTHERLY SURFACE WINDS WILL SET UP OVER THE TERMINALS WITH
WINDS INCREASING TO 20 TO 25 KTS SUSTAINED AND GUSTS UP TO 35 KTS
IN THE LATE MORNING INTO THE AFTERNOON. A STRONG COLD FRONT WILL
MOVE INTO THE TERMINALS AFTER THIS TAF PERIOD...SO WILL LEAVE THE
WIND SHIFT AND LOWERING CEILINGS FOR LATER TAF ISSUANCES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-027.
WINTER WEATHER ADVISORY FROM 10 PM MST /11 PM CST/ WEDNESDAY TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ003-004-014>016-028-029-
041-042.
CO...WINTER WEATHER ADVISORY FROM 7 PM WEDNESDAY TO 6 AM MST THURSDAY
FOR COZ090>092.
NE...WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
&&
$$
UPDATE...RRH
SHORT TERM...DJR
LONG TERM...BULLER
AVIATION...ALW
AREA FORECAST DISCUSSION...UPDATED
NWS NEW ORLEANS LA
729 PM CST THU FEB 20 2014
.UPDATE...
UPDATED FORECAST PACKAGE TO REFLECT TORNADO WATCH FOR THE ENTIRE
CWA UNTIL 09Z FRIDAY. 14/MM
&&
.PREV DISCUSSION... /ISSUED 344 PM CST THU FEB 20 2014/
SHORT TERM...
BIGGEST IMPACT OVER THE FORECAST PERIOD WILL BE OVER THE NEXT 12 TO
15 HOURS. AN UPPER LEVEL TROUGH IS CURRENTLY MOVING ACROSS THE
NORTHERN AND CENTRAL PLAINS OF THE UNITED STATES. THE TIGHTEST CURL
AT THE BASE OF THE LOW IS NOW STARTING TO CURL NORTHEAST TOWARDS THE
UPPER MISSISSIPPI VALLEY. THE ASSOCIATED COLD FRONT IS NOW MOVING
SOUTHEAST OVER EASTERN TEXAS AND JUST ENTERING THE EXTREME
NORTHWESTERN LOUISIANA PARISHES. LATEST RADAR IMAGERY SHOWS A LINE
OF THUNDERSTORMS HAS DEVELOPED ALONG AND AHEAD OF THE LEADING EDGE OF
THE COLD FRONT. MORE LOCALLY...SHOWERS ARE BEGINNING TO INCREASE IN
COVERAGE OVER MOST OF THE CWA. MODELS SHOW THIS TREND CONTINUING
THROUGH THE REST OF THE AFTERNOON. MODEL SOUNDINGS INDICATE THAT
ELEVATED INSTABILITY DOES EXIST OVER THE AREA RIGHT NOW WITH A
SLIGHTLY WARM NOSE JUST ABOVE 700MB. THIS WILL ERODE OVER THE NEXT
FEW HOURS WHICH COULD ALLOW FOR A A FEW STORMS TO INTENSIFY AND
LIKELY START PRODUCING THUNDER. THE NCEP WRF WAS THE MOST AGGRESSIVE
WITH MORE DISCRETE CELLS BEING DEPICTED ON IT. LOOKS TO BE THE
OUTLIAR OF MESO AND MEDIUM RANGE MODELS. THE MAIN PLAYER THIS
EVENING SHOULD BE STORMS ALONG AND JUST AHEAD OF THE COLD FRONT AS
IT MARCHES THROUGH THE FORECAST AREA WHERE DYNAMICAL LIFT WILL BE
THE GREATEST. IT WILL HAVE TO OVERCOME PRETTY SIGNIFICANTLY
DEVELOPING INVERSION WHILE COMING THROUGH. WITH THAT TYPE OF LIFT
AND FAIRLY STRONG WINDS THROUGH THE COLUMN...40 TO 50 KNOTS...THERE
WILL BE A THREAT FOR STRONG TO SEVERE WINDS ALONG THE FRONT. A
TORNADO IS NOT OUT OF THE QUESTION EITHER. THE RISK WILL BE GREATEST
IN SOUTHWEST MISSISSIPPI AND ADJACENT LOUISIANA PARISHES WITH
DECREASING THREAT TO THE SOUTH TOWARDS THE COAST. HRRR LOOKS TO
PRETTY SPOT ON IN TERMS OF INITIALIZATION OF THE CURRENT SQUALL
LINE POSITION AND MOVEMENT. CARRYING THAT OUT IN TIME BRINGS THE
LINE TO NWRN ZONES BY 02Z AND NEW ORLEANS METRO BY 06Z. SHOULD BE
FINISHING UP OVER LAND AREAS WITH STRONGER ACTIVITY BY AROUND 09Z
WITH LINGERING SHOWERS TRAILING BY A FEW HOURS. WOULD NOT BE
SURPRISED TO SEE A SEVERE WATCH PUT OUT FOR MUCH IF NOT ALL OF THE
AREA DURING THE EVENING AND EARLY MORNING HOURS. FOR THE POPS...KEPT
IT SIMPLE AND HAVE A PEAK OF 100 PCT ACROSS THE ENTIRE CWA. THE RAIN
SHOULD THEN TAPER OFF VERY QUICKLY CLOSING IN ON 12Z FRIDAY. BY THIS
POINT...ONLY EXTREME COASTAL LOCATIONS OF MS/LA AND SOUTHWARD SHOULD
HAVE ANY SHOWERS LEFT. THE COLD FRONT WILL CONTINUE SOUTH AND STALL
IN THE CENTRAL GULF OF MEXICO.
LONG TERM...
ZONAL FLOW WILL RETURN ON SATURDAY AND REMAIN IN PLACE FOR A FEW
DAYS. BUILDING UPPER LEVEL RIDGE WELL TO THE SOUTH OF THE FORECAST
AREA WHICH WILL BRING THE PREVIOUS BOUNDARY BACK NORTH TO THE GULF
COAST. THIS WILL LIKELY BE THE FOCUS FOR SCATTERED SHOWERS AND
POSSIBLY A FEW THUNDERSTORMS BEGINNING ON SUNDAY. HAVE INCREASED
POPS QUITE A BIT ON SUNDAY TO BE MORE IN LINE WITH BOTH GFS AND
ECMWF QPF OUTPUTS. SLIGHTLY BELOW MEX BUT NOT BY MUCH. TEMPERATURES
WILL BE AT OR ABOVE NORMAL THROUGH THE ENTIRE FORECAST PERIOD.
MEFFER
MARINE...
STILL SEEING SOME LINGERING FOG OVER THE NEARSHORE WATERS NEAR AND
WEST OF THE MISSISSIPPI RIVER. WILL CONTINUE ADVISORY IN THOSE
COASTAL ZONES UNTIL MIDNIGHT. AFTER MIDNIGHT...WIND INCREASE SHOULD
MIX OUT FOG. WILL DROP ADVISORY OVER THE SOUNDS WITH FORECAST
ISSUANCE.
WILL HAVE A PERIOD OF EXERCISE CAUTION WINDS OVER PORTIONS OF THE
EASTERN OPEN WATERS OVERNIGHT...BUT WINDS ARE EXPECTED TO RELAX
SLIGHTLY DURING THE DAY ON THURSDAY. EXPECT SMALL CRAFT ADVISORY TO
BE NECESSARY ON FRIDAY BEHIND THE COLD FRONT...WITH WINDS EASING BY
EVENING. QUIET CONDITIONS EXPECTED BEYOND FRIDAY FOR THE WEEKEND. 35
AVIATION...
ONSHORE FLOW WELL ESTABLISHED TODAY WITH MVFR TO VFR CEILINGS
COMMON. GENERALLY SEEING LOWER DECK IN FL015-025 RANGE AND SECOND
DECK IN FL035-050 LAYER. THESE WILL OCCASIONALLY SCATTER OUT AND
THEN FILL BACK IN. HAVE MADE LITTLE CHANGE IN TIMING OF LINE OF
CONVECTION THAT IS JUST NOW BEGINNING TO DEVELOP NORTHWEST OF
SHREVEPORT...18Z TAF PACKAGE TIMING STILL REASONABLE. STILL
POTENTIAL FOR SEVERE WIND GUSTS WITH THIS LINE AS WELL AS TEMPORARY
IFR CEILINGS/VISIBILITIES. THE THUNDERSTORMS WILL BE NEAR OR JUST
AHEAD OF COLD FRONT WITH A QUICK SHIFT TO NORTHWEST WINDS BEHIND
FRONT. ANTICIPATE SEVERAL HOURS OF GUSTY WINDS BEHIND THE
FRONT...POSSIBLY GUSTING ABOVE 30 KNOTS DOWNWIND OF LAKE
PONTCHARTRAIN AT KMSY AND KNEW. CLOUDS EXPECTED TO CLEAR OUT RAPIDLY
BEHIND THE FRONT FRIDAY MORNING. 35
DECISION SUPPORT...
DSS CODE...BLUE WITH POSSIBLE UPGRADE THIS EVENING
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
MONITORING TSTM THREAT FOR THIS EVE/TONIGHT.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 45 66 37 70 / 100 10 0 0
BTR 47 67 42 73 / 100 10 0 0
ASD 51 67 38 69 / 100 10 0 0
MSY 53 66 47 68 / 100 10 0 0
GPT 51 66 40 66 / 100 10 0 0
PQL 50 68 37 69 / 100 20 0 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY FROM MIDNIGHT FRIDAY TO NOON FRIDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...COASTAL
WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM
PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL
WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON
TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM
STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST
PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO
60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
MS...NONE.
GM...SMALL CRAFT ADVISORY FROM MIDNIGHT FRIDAY TO NOON FRIDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...COASTAL
WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM
PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL
WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON
TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM
STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST
PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO
60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1011 PM EST THU FEB 20 2014
.SYNOPSIS...
A WARM FRONT WILL NORTH OF THE REGION OVERNIGHT. A COLD FRONT
CROSSES THE MID ATLANTIC REGION ON FRIDAY. HIGH PRESSURE AND
DRIER CONDITIONS RETURN TO THE REGION DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
VRB CLDS TO MCLDY ACRS THE FA. WARM FRONT RMNS SLO TO MOVE N
THROUGH THE RGN THIS EVE...WILL DO SO...W/ LAST PLACES TO LOSE THE
LO LVL WEDGE WNW OF RIC. MDLS DIFFER AS TO LO CIGS OR DEVELOPMENT.
WILL INCLUDE AREAS OF FG OVR PORTIONS OF THE WTRS OVRNGT AS THE
WARM AIR PUSHES NWD OVR THE COLDER BAY/OCN WTRS...OTRW CONTG W/
MNLY MCLDY SKY COVER. LO TEMPS ABT REACHED IN MOST PLACES...ESP
SRN VA/NE NC. A RISE IN TEMPS XPCD IN ALL AREAS AS WARM FRONT
CONTS N.
HAVE CUTBACK POPS TO 20-30% (LATE TNGT) ALG/W OF I 95 FOR SLOWER
ARRIVAL TO PCPN. ELSW...POPS AOB 10%.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
SCA REMAIN IN EFFECT FOR ALL THE WATERS BEGINNING AT 06Z/1 AM.
CONDITIONS MAY BE DELAYED IN MOST INSTANCES DUE TO THE COLD WATER
TEMPERATURES. ALREADY SEEING A LARGE DIFFERENCE BETWEEN SENSORS
NEAR THE WATER AND ELEVATED ONES. THE MOST IMPRESSIVE IS
CHESAPEAKE LIGHT BUOY ABOUT 15 MILES OFF VIRGINIA BEACH RECORDING
SUSTAINED 30 KNOTS AT ABOUT 40 METERS WHILE MANY SENSORS NEAR THE
WATER STRUGGLE TO REACH 10 KNOTS. NAM TRANS WINDS FROM THE 12Z
NAM12 RUN IN THE BAY ARE 16 TO 18 KNOTS OVERNIGHT. USUALLY THESE
REFLECT FAIRLY CLOSELY THE WINDS AT THE WATER SURFACE. THE WINDS
SHOULD EASILY TO SCA THRESHOLDS DURING THE DAY FRIDAY.
PREVIOUS DISCUSSION...
HIGH PRESSURE HAS PUSHED OFFSHORE THIS AFTERNOON AS A WARM FRONT
LIFTS NWD FROM NC. BENIGN CONDITIONS (WINDS GENERALLY AOB 5-10 KT)
OVER THE WATERS WILL QUICKLY GIVE WAY TO INCREASING SLY WINDS THIS
EVENING THROUGH TONIGHT AS THE WARM FRONT LIFTS OVER OF THE
WATERS. GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A
STRONG COLD FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND
MIDNIGHT TONIGHT. WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT
THE STRONGEST WINDS ALOFT FROM REACHING THE WATER...PRESSURE FALLS
AND THE TIGHT GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY
AND 20-30 KT OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE
INTO FRI BEFORE THE COLD FRONT CROSSES THE WATERS FRIDAY
AFTERNOON. SHOWERS AND THUNDERSTORMS WILL ALSO ACCOMPANY THE
FRONT...WHICH MAY PRODUCE STRONGER WIND GUSTS WITH CONVECTION. AS
THE FRONT CROSSES THE WATERS AND WINDS BACK TO THE NW...ANTICIPATE
A QUICK SURGE POST FRONTAL BEFORE WINDS DIMINISH FRIDAY NIGHT AS
HIGH PRESSURE BUILDS IN FROM THE SOUTHWEST. WAVES MAY BRIEFLY
INCREASE TO 4 FT AROUND MIDDAY FRIDAY ON THE BAY. MEANWHILE...SEAS
WILL BUILD TO 5-6 FT ON THE SOUTHERN COASTAL WATERS...AND 6-8 FT
ON THE NORTHERN COASTAL WATERS. HEADLINES ARE IN EFFECT FOR ALL
WATERS FROM AFTER MIDNIGHT TONIGHT THROUGH 4PM FRIDAY. RIVERS DROP
OFF FIRST BEFORE THE BAY AT 6PM AND THE NRN COASTAL WATERS AT
MIDNIGHT FRI NIGHT. HIGH PRESSURE REMAINS OVER THE WATERS THROUGH
THE WEEKEND BEFORE A CLIPPER FRONT CROSSES THE WATERS SUNDAY
NIGHT-MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
ANZ650-652-654.
SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR ANZ656-658.
&&
$$
SYNOPSIS...ALB/BMD
NEAR TERM...ALB/BMD
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM/LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
938 PM EST THU FEB 20 2014
.SYNOPSIS...
A WARM FRONT WILL NORTH OF THE REGION OVERNIGHT. A COLD FRONT
CROSSES THE MID ATLANTIC REGION ON FRIDAY. HIGH PRESSURE AND
DRIER CONDITIONS RETURN TO THE REGION DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
VRB CLDS TO MCLDY ACRS THE FA. WARM FRONT RMNS SLO TO MOVE N
THROUGH THE RGN THIS EVE...WILL DO SO...W/ LAST PLACES TO LOSE THE
LO LVL WEDGE WNW OF RIC. MDLS DIFFER AS TO LO CIGS OR DEVELOPMENT.
WILL INCLUDE AREAS OF FG OVR PORTIONS OF THE WTRS OVRNGT AS THE
WARM AIR PUSHES NWD OVR THE COLDER BAY/OCN WTRS...OTRW CONTG W/
MNLY MCLDY SKY COVER. LO TEMPS ABT REACHED IN MOST PLACES...ESP
SRN VA/NE NC. A RISE IN TEMPS XPCD IN ALL AREAS AS WARM FRONT
CONTS N.
HAVE CUTBACK POPS TO 20-30% (LATE TNGT) ALG/W OF I 95 FOR SLOWER
ARRIVAL TO PCPN. ELSW...POPS AOB 10%.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
HIGH PRESSURE HAS PUSHED OFFSHORE THIS AFTERNOON AS A WARM FRONT
LIFTS NWD FROM NC. BENIGN CONDITIONS (WINDS GENERALLY AOB 5-10 KT)
OVER THE WATERS WILL QUICKLY GIVE WAY TO INCREASING SLY WINDS THIS
EVENING THROUGH TONIGHT AS THE WARM FRONT LIFTS OVER OF THE WATERS.
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG COLD
FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT TONIGHT.
WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE STRONGEST WINDS
ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND THE TIGHT
GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND 20-30 KT
OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO FRI BEFORE
THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON. SHOWERS AND
THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH MAY PRODUCE
STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT CROSSES THE WATERS
AND WINDS BACK TO THE NW...ANTICIPATE A QUICK SURGE POST FRONTAL
BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH PRESSURE BUILDS IN FROM
THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE TO 4 FT AROUND MIDDAY
FRIDAY ON THE BAY. MEANWHILE...SEAS WILL BUILD TO 5-6 FT ON THE
SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE NORTHERN COASTAL WATERS.
HEADLINES ARE IN EFFECT FOR ALL WATERS FROM AFTER MIDNIGHT TONIGHT
THROUGH 4PM FRIDAY. RIVERS DROP OFF FIRST BEFORE THE BAY AT 6PM AND
THE NRN COASTAL WATERS AT MIDNIGHT FRI NIGHT. HIGH PRESSURE REMAINS
OVER THE WATERS THROUGH THE WEEKEND BEFORE A CLIPPER FRONT CROSSES
THE WATERS SUNDAY NIGHT-MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST FRIDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST FRIDAY FOR
ANZ630>634.
SMALL CRAFT ADVISORY FROM 1 AM FRIDAY TO MIDNIGHT EST FRIDAY
NIGHT FOR ANZ650-652-654.
SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST FRIDAY FOR ANZ656-
658.
&&
$$
SYNOPSIS...ALB/BMD
NEAR TERM...ALB/BMD
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
804 PM EST THU FEB 20 2014
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY ACROSS NORTH CAROLINA THIS EVENING WILL
LIFT NORTH AS A WARM FRONT LATER TONIGHT. A COLD FRONT CROSSES THE
MID ATLANTIC REGION ON FRIDAY. HIGH PRESSURE AND DRIER CONDITIONS
RETURN TO THE REGION DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
VARIABLE CLOUDINESS TODAY WILL CONTINUE THROUGH TONIGHT. PLENTY OF
INSTABILITY IN THE FORM OF ACCAS CLOUDS (VIA VISIBLE SATELLITE
IMAGERY) CAN BE SEEN ALONG AND SOUTH OF A WARM FRONT STALLED
ACROSS NORTH CAROLINA LATE THIS AFTN. WILL NEED TO MONITOR THE
LOCATION/PROGRESS OF THE ACCAS INTO FAR WRN PORTIONS OF THE FA
LATE TONIGHT AS THE WARM FRONT LIFTS THROUGH THE REGION. HAVE
LIMITED POPS TO 10 PERCENT FOR THE PIEDMONT OVERNIGHT. GUSTY SOUTH
WINDS WILL DEVELOP AFTER MIDNIGHT BEHIND THE WARM FRONT AND
TEMPS/DEWPOINTS WILL START TO RISE. TEMPS SHOULD BOTTOM OUT
SHORTLY AFTER MIDNIGHT WITH LOWS IN THE LOWER 50S NORTH TO AROUND
60 DEGREES SOUTH. BY DAYBREAK...TEMPS SHOULD BE IN THE MID 50S
NORTH TO LOWER 60S SOUTH.
MEANWHILE...A STRONG LOW PRESSURE SYSTEM IN THE MIDWEST WILL TRACK
ALMOST DUE NORTH INTO THE GREAT LAKES REGION TONIGHT. THIS WILL
SHIFT THE UPPER LEVEL JET DYNAMICS INTO A MORE NORTH-TO-SOUTH
ORIENTATION AND WILL LIKELY DELAY THE ONSET OF PRECIPITATION BY A
FEW HOURS. THEREFORE PRECIP IS NOT EXPECTED TO MOVE INTO FAR WRN
PORTIONS OF THE FA UNTIL JUST AFTER DAYBREAK...HOWEVER ISENTROPIC
LIFT ADVECTING MOISTURE INTO THE PIEDMONT/CTRL VA MAY BE ENOUGH TO
SUPPORT SHOWERS JUST PRIOR TO SUNRISE. DUE TO SLOWER TIMING...HAVE
CUT BACK ON PRECIP CHANCES IN WRN AREAS TO 30 PERCENT PRE-DAWN TO
60-70 PERCENT JUST AFTER DAYBREAK.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
HIGH PRESSURE HAS PUSHED OFFSHORE THIS AFTERNOON AS A WARM FRONT
LIFTS NWD FROM NC. BENIGN CONDITIONS (WINDS GENERALLY AOB 5-10 KT)
OVER THE WATERS WILL QUICKLY GIVE WAY TO INCREASING SLY WINDS THIS
EVENING THROUGH TONIGHT AS THE WARM FRONT LIFTS OVER OF THE WATERS.
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG COLD
FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT TONIGHT.
WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE STRONGEST WINDS
ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND THE TIGHT
GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND 20-30 KT
OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO FRI BEFORE
THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON. SHOWERS AND
THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH MAY PRODUCE
STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT CROSSES THE WATERS
AND WINDS BACK TO THE NW...ANTICIPATE A QUICK SURGE POST FRONTAL
BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH PRESSURE BUILDS IN FROM
THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE TO 4 FT AROUND MIDDAY
FRIDAY ON THE BAY. MEANWHILE...SEAS WILL BUILD TO 5-6 FT ON THE
SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE NORTHERN COASTAL WATERS.
HEADLINES ARE IN EFFECT FOR ALL WATERS FROM AFTER MIDNIGHT TONIGHT
THROUGH 4PM FRIDAY. RIVERS DROP OFF FIRST BEFORE THE BAY AT 6PM AND
THE NRN COASTAL WATERS AT MIDNIGHT FRI NIGHT. HIGH PRESSURE REMAINS
OVER THE WATERS THROUGH THE WEEKEND BEFORE A CLIPPER FRONT CROSSES
THE WATERS SUNDAY NIGHT-MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST FRIDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST FRIDAY FOR
ANZ630>634.
SMALL CRAFT ADVISORY FROM 1 AM FRIDAY TO MIDNIGHT EST FRIDAY
NIGHT FOR ANZ650-652-654.
SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST FRIDAY FOR ANZ656-
658.
&&
$$
SYNOPSIS...BMD
NEAR TERM...BMD
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1032 AM EST WED FEB 19 2014
.SYNOPSIS...
A COLD FRONT SAGGING ACROSS THE EASTERN OHIO VALLEY WILL CROSS
THE AREA THIS AFTERNOON. HIGH PRESSURE WILL RETURN TONIGHT AND
THEN DRIFT OFFSHORE THURSDAY. A STRONGER COLD FRONT MOVES THROUGH
FRIDAY. HIGH PRESSURE WILL THEN RETURN OVER THE WEEKEND. LOW
PRESSURE APPROACHES THE REGION TUESDAY OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 10AM...A BAND OF RAIN IS MOVING EAST ACROSS THE I-95
CORRIDOR TOWARD THE CHESAPEAKE BAY. IN PLACES WHERE TEMPERATURES
ARE AT OR JUST BELOW FREEZING...WE HAVE EXTENDED OUR FREEZING RAIN
ADVISORY FOR FREDERICK...CARROLL AND NORTHERN BALTIMORE COUNTIES
THROUGH NOON.
THERE HAVE ALSO BEEN REPORTS OF LIGHTNING AND THUNDER...EITHER BY
STORM SPOTTERS OR BY LIGHTNING DETECTION. MUCH...IF NOT ALL...OF
THE LIGHTNING IS ELEVATED-BASED SINCE WE HAD A MODERATE TO STRONG
INVERSION IN THE BOUNDARY LAYER BUT STEEP LAPSE RATES BETWEEN
850MB AND 700MB. ALSO CONTRIBUTING TO THE ELEVATED CONVECTION IS
A 45 KNOT LOW LEVEL JET AROUND 2000 FEET...A JET STREAK POKING
INTO THE WESTERN PORTION OF OUR REGION FROM THE EASTERN OHIO
VALLEY...AND SOME GOOD PVA WITH A 500 MB SHORTWAVE SLIDING ACROSS
SOUTHERN PENNSYLVANIA.
CONDITIONS WILL IMPROVE FROM WEST TO EAST LATER THIS MORNING AND
AFTERNOON AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
PREVIOUS DISCO...
SFC ANALY ALSO SUGGESTING THERE MAY BE A HINT OF A WMFNT
ACRS CWFA...ROUGHLY DOWN THE PTMC. THE CORE OF THE COLD AIR /TEMPS
IN THE TEENS/ IS OVER NEW ENGLAND...BUT SUBFRZG AIR CAN BE FOUND
IN THE PTMC HIGHLANDS AND ACRS NRN MD. MEANWHILE... STRONG ISENT
LIFT IS PRODUCING AN AREA OF PCPN IN THE OH/TN VLYS AND ACRS THE
MTNS OF NC. THAT LIFT...AND THE ASSOC PCPN /WHICH IS ALL
RA/...PROGGED TO ARRIVE IN THE CWFA BTWN 12-14 UTC. HV INCRSD POPS
AND DELAYED TIMING BASED ON LTST GDNC. QSTN REMAINS WHAT WL THE
SFC TEMPS BE WHEN RAIN ARRIVES.
MDL SNDGS...SPCLY FM THE NAM...SUGGEST THAT A STRONG WARM NOSE WL
RESIDE ARND H9 BUT SFC TEMPS WL STILL BE BLO FRZG. GFS IS WARMER AT
THE SFC AND HAS A LESS PRONOUNCED WARM AIR INTRUSION. RAP BTWN THE
TWO THERMALLY...BUT HAS A LATE PCPN ONSET. SINCE NRN MD HAS A SOLID
SNOWPACK...THINK THE NAM IS ONTO SOMETHING...AND PREFER ITS SOLN FOR
THE MRNG. WE HV A FZRA ADVY IN PLACE FOR NRN MD...AND WL BE KEEPING
THAT GOING. ONLY CONCERN IS WHETHER THE NRN PORTION OF THE ERN WVA
PANHNDL /MINERAL TO JEFFERSON CNTYS/ SHUD BE INCLUDED. GRIDS FM 00Z
NAM/GMOS BLENDED IN FCST DATABASE. MUST ADMIT ITS A CLOSE CALL...
BUT SIGNS POINT TO JUST SQUEAKING IT OUT. WL MONITOR CLOSELY...BUT
HV OPTED TO NOT EXPAND CVRG ATTM.
CDFNT CROSSES CWFA DURING THE AFTN HRS...W/ STRONG CAA /AND DP
MIXING/ IN ITS WAKE. AM XPCTG A BRZY AFTN CONSIDERING WNDS AVBL BTWN
H8 AND SFC. WENT ON THE RESERVED SIDE IN DATABASE...KEEPING GUSTS
20-30 MPH. IF FULL MIXING TRANSPIRES...IT MAY BE MORE THAN THAT.
PAST FEW DAYS...TEMPS HV BEEN WARMER THAN PROGGED. SINCE CAA WL BE
ARRIVING LT IN THE DAY...AND WL BE ACCMPNYD BY COMPRESSIONAL
WARMING...WENT ON THE WARM SIDE OF GDNC FOR MAXT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
RDGG /SFC-H7/ WL BUILD ATOP CWFA TNGT...AND PROGRESS TO THE DELMARVA
THU MRNG. AM XPCTG MOCLR SKIES/DIMINISHING WNDS TNGT...AND MIN-T
FLLW SUIT.
BY THU...WL BE BACK IN RTN FLOW...AND SHUD HV A MID DECK CLDS
OVERSPREADING AREA ONCE AGN. THESE CLDS WL THICKEN THRUT THE DAY AS
ISENT LIFT STRENGTHENS. WHILE SOME MDL FIELDS SUGGEST THERE MAY BE A
LTL PCPN BY THE END OF THE DAY...POPS REMAIN VERY LOW. HV
ENTERTAINED A SCHC IN THE NWRN CORNER OF CWFA ONLY...WHICH WUD BE
NEARER A DVLPG WMFNT.
A LTL VARIANCE NOTED IN THU MAXT...BUT ALL GDNC WARMER THAN PRVS
FCST. HV RAISED TEMPS ACCRDGLY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY EVENING BEGINS WITH A WARM FRONT LOCATED TO THE SOUTH OF
THE AREA...BUT MODELS SHOW A STRENGTHENING LOW LEVEL JET AND
SOUTHERLY BOUNDARY LAYER WINDS LOOK STRONG ENOUGH TO SEND THIS WARM
FRONT NORTHWARD DURING THE NIGHT THURSDAY. SOME RAIN AND FOG ARE
POSSIBLE THURSDAY NIGHT...BUT AS QUICKLY AS THE WARM FRONT LIFTS
TO THE NORTH A COLD FRONT WILL BE APPROACHING FROM THE WEST.
MODELS/ENSEMBLES HAVE TRENDED FASTER...WITH SHOWERS MOVING INTO THE
POTOMAC HIGHLANDS LATE THURSDAY NIGHT AND THEN AFFECTING THE CWA
PRIMARILY FRIDAY MORNING AND EXITING DURING THE AFTERNOON. A FASTER
PASSAGE MAY HELP LIMIT INSTABILITY AND WIDESPREAD SEVERE...HOWEVER
STRONG WINDS IN THE LOW LEVELS MAY BE TRANSPORTED DOWN TO THE
SURFACE EVEN IN ABSENCE OF THUNDERSTORMS /I.E. WITH ONLY SHOWERS/
AND THUS LOCALLY DAMAGING WINDS WILL BE POSSIBLE IN A HIGH SHEAR
BUT LOW/LITTLE CAPE ENVIRONMENT.
MAXIMA MAY WIND UP OCCURRING DURING FRIDAY MORNING...WITH
TEMPERATURES DROPPING BEHIND THE FRONT LATER FRIDAY. ATTEMPTED TO
REFLECT SOME TIMING DETAILS IN THE GRIDS...INCLUDING FOR
MINIMA/MAXIMA THURSDAY NIGHT/FRIDAY.
DRIER AIR MOVES IN FOR FRIDAY NIGHT AND SATURDAY AND THUS THE RETURN
OF SUNSHINE IS EXPECTED FOR SATURDAY. WITH GOOD INSOLATION AND A
SOUTHWEST FLOW...SATURDAY LOOKS LIKE A MILD DAY WITH MAXIMA 10 PLUS
DEGREES ABOVE AVERAGE.
A REINFORCING COLD FRONT IS EXPECTED ON SUNDAY. ASIDE FROM SOME
CLOUDS AND SILENT POPS OVER THE HIGHLANDS...FRONT LIKELY PASSES
THROUGH RATHER QUIETLY. HIGH PRESSURE BUILDING IN BEHIND THE FRONT
WILL HOWEVER HAVE SOME COOLER AIR WITH IT /NEAR AVERAGE FOR THIS
TIME OF THE YEAR/ WHICH WILL TAKE HOLD OF THE MID-ATLANTIC EARLY
NEXT WEEK.
NEXT STORM SYSTEM APPROACHES ON TUESDAY...AND HAVE BUMPED POPS UP TO
CHANCE. UNCERTAINTY IN P-TYPE EXISTS AND HAVE GENERIC RAIN OR SNOW
WORDING.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
SOME MVFR CONDITIONS FOR ANOTHER HOUR OR TWO NEAR DCA...BWI...AND
MTN WITH RAIN MOVING EAST. VFR CONDITIONS AFTERWARDS. THERE IS A
THREAT FOR SOME LOW LEVEL WIND SHEAR THROUGH MIDDAY WITH AN
APPROACHING FRONT.
PCPN SHUD BE GONE BY MIDDAY...AND A WSHFT DURING THE AFTN WL
ACCOMPANY A CDFNT. WLY WNDS G25KT LKLY POST FROPA...BUT GRADIENT
/AND WNDS/ WL RELAX AFDK.
HIPRES OVNGT WL NO CIGS AND LTL WND. SLY FLOW WL RESUME THU MRNG...
INCRSG AGN DURING THE AFTN. CIGS WL DVLP AND LWR...BUT SHUD REMAIN
DRY THRU THE DAY W/ VFR CONDS PREVAILING.
THURSDAY NIGHT...FLIGHT RESTRICTIONS MAY DEVELOP IN SOME RAIN/FOG.
SREFS SUGGESTS AT LEAST IFR...WITH SUPPORT FROM MAV/MET. STRONG LLJ
WILL ALSO BRING THE LIKELIHOOD OF LOW LEVEL WIND SHEAR.
FRIDAY...COLD FRONT MOVES ACROSS THE AREA WITH SHOWERS. SHOWERS
COULD TRANSPORT STRONG GUSTY WINDS TO THE SURFACE. FROPA MAY WIND UP
BEING IN THE MORNING...ALTHOUGH EXACT TIMING IS STILL SOMEWHAT
UNCERTAIN.
SATURDAY INTO EARLY NEXT WEEK...HIGH PRESSURE BUILDS IN FOR NO
SIGNIFICANT WEATHER THROUGH MONDAY. NEXT STORM APPROACHES WITH A
CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
WNDS WL INCRS TDA AHD OF CDFNT. A STRONG SLY LLJ WL DVLP THIS
MRNG. WHILE THERE WL BE A STRONG INVSN WHICH WL TRAP MOST OF THE
WNDS OFF THE WATERS SFC...THE MAGNITUDE OF WND AND PRESENCE OF RA
MAY MIX A LTL DOWN. HV OPTED TO KEEP SCA GOING FOR MID BAY AND LWR
PTMC... ALTHO ITS NOT OF THE HIEST CONFIDENCE.
POST FROPA THERE IS A GOOD MIXED PROFILE FOR A FEW HRS. SCA IN
EFFECT FOR ALL WATERS TAFTN. THE CFP MAY BE A LTL LATER THAN PRVSLY
PROGGED...AND HV XTNDD SCA FOR THE WATERS INTO ELY EVNG PTMC AND MID
EVNG LWR PTMC/BAY.
GRADIENT WL RELAX OVNGT UNDER HIPRES. SLY FLOW WL RESUME THU. WHILE
GRADIENT INCREASES ONCE AGN...THINK THAT MIXING WL HOLD OFF...AND HV
KEPT WNDS UNDER SCA THRESHOLDS.
STRONG SOUTHERLY JET WILL BE IN PLACE THURSDAY NIGHT. A FRACTION OF
WIND ALOFT WILL LIKELY BE ABLE TO MIX DOWN OVERNIGHT FOR SCA
CONDITIONS. WINDS INCREASE FURTHER FRIDAY MORNING AHEAD OF A COLD
FRONT...POSSIBLY NEAR GALES. SHOWERS ASSOCIATED WITH THE FRONT MAY
ALSO BRING DOWN STRONG GUSTY WINDS. FRONT SHOULD MOVE EAST OF THE
WATERS FRIDAY AFTERNOON. HIGH PRESSURE BUILDS IN OVER THE WEEKEND.
&&
.HYDROLOGY...
WILL BE WATCHING SNOWMELT THIS WEEK AS THE WARMUP ENSUES. SNOW WATER
EQUIVALENT VALUES RANGE FROM LESS THAN AN INCH ALONG AND EAST OF
INTERSTATE 95 TO MORE THAN TWO INCHES WEST OF THE BLUE RIDGE AND
ALONG THE MASON DIXON LINE. OBSERVED SNOW WATER EQUIVALENT IS AROUND
4 INCHES IN THE POTOMAC HIGHLANDS /BUT THE HIGHEST VALUES ARE MAINLY
UPSTREAM OF JENNINGS RANDOLPH AND SAVAGE RIVER LAKES/.
A GRADUAL MELT IS EXPECTED IN THE COMING DAYS...SLIGHTLY MORE
PRONOUNCED THU INTO FRI AS LOWS STAY ABOVE FREEZING THURSDAY NIGHT.
IF MODERATE TO HEAVY PRECIPITATION OCCURRED COINCIDENT WITH THE
MELT...CONCERN WOULD BE HIGH FOR FLOODING. HOWEVER...AT THIS TIME...
RAIN AMOUNTS THROUGH FRIDAY ARE EXPECTED TO BE A HALF INCH OR LESS.
AT THIS TIME THE MOST LIKELY SCENARIO SEEMS TO BE A STEADY
WITHIN-BANK RISE OF STREAMS AND RIVERS LATE THIS WEEK AND INTO THE
WEEKEND. IF RAIN AND/OR SNOWMELT ARE MORE THAN CURRENTLY EXPECTED...
THE FLOOD THREAT WOULD INCREASE ACCORDINGLY FRIDAY AND SATURDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR MDZ004>006.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR
ANZ530>534-537>543.
SMALL CRAFT ADVISORY UNTIL 8 PM EST THIS EVENING FOR ANZ535-
536.
&&
$$
SYNOPSIS...BPP/KLW
NEAR TERM...HTS/KLW
SHORT TERM...HTS
LONG TERM...BPP
AVIATION...BPP/KLW
MARINE...BPP/HTS
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
655 AM EST WED FEB 19 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA TODAY. HIGH PRESSURE WILL RETURN
TONIGHT AND THEN DRIFT OFFSHORE THURSDAY. A STRONGER COLD FRONT
MOVES THROUGH FRIDAY. HIGH PRESSURE WILL THEN RETURN OVER THE
WEEKEND. LOW PRESSURE APPROACHES THE REGION TUESDAY OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDT...
06Z NAM COME IN JUST AS COLD AS THE 00Z RUN. IN ADDITION...REPORTS
FM UPSTREAM SUGGEST ICING OCCURRING EVEN WHERE SFC TEMPS ABV FRZG
DUE TO COLD GRND. LAMP TEMPS HV TRENDED COLDER AS LINE OF PCPN MVS
EWD AND ADDTL PCPN DVLPS E OF MAIN AREA. THAT LEADS TO A GREATER
CONCERN. BASED ON LAMP AND MESO OBS...HV MADE A FAIRLY SIZEABLE
EXPANSION TO FZRA ADVY TO INCL EVERYTHING BTWN APLCNS AND BLURDG
AS WELL AS LOUDOUN- MONTCO- HOWARD AND PRINCE WM CNTYS. FZRA SHUD
BE PATCHY IN LINE W/ SFC TEMPS...BUT ITS PSBL TO GET SOME ICING
EVEN WHERE AIR TEMPS ABV FRZG. HOPEFULLY W/ DAYLIGHT UPON US...
THESE THREATS SHUD BE RATHER SHORT LIVED. KEPT ENDING TIME AT 10AM
FOR ALL CNTYS WHERE ITS VALID.
PRVS DSCN FLLWS...
LOPRES OVER LK SUPERIOR ELY THIS MRNG...W/ AN ATTENDENT CDFNT FM
ORD DOWN THE MID-LWR MS RVR VLY. SFC ANALY ALSO SUGGESTING THERE
MAY BE A HINT OF A WMFNT ACRS CWFA...ROUGHLY DOWN THE PTMC. THE
CORE OF THE COLD AIR /TEMPS IN THE TEENS/ IS OVER NEW
ENGLAND...BUT SUBFRZG AIR CAN BE FOUND IN THE PTMC HIGHLANDS AND
ACRS NRN MD. MEANWHILE... STRONG ISENT LIFT IS PRODUCING AN AREA
OF PCPN IN THE OH/TN VLYS AND ACRS THE MTNS OF NC. THAT LIFT...AND
THE ASSOC PCPN /WHICH IS ALL RA/...PROGGED TO ARRIVE IN THE CWFA
BTWN 12-14 UTC. HV INCRSD POPS AND DELAYED TIMING BASED ON LTST
GDNC. QSTN REMAINS WHAT WL THE SFC TEMPS BE WHEN RAIN ARRIVES.
MDL SNDGS...SPCLY FM THE NAM...SUGGEST THAT A STRONG WARM NOSE WL
RESIDE ARND H9 BUT SFC TEMPS WL STILL BE BLO FRZG. GFS IS WARMER AT
THE SFC AND HAS A LESS PRONOUNCED WARM AIR INTRUSION. RAP BTWN THE
TWO THERMALLY...BUT HAS A LATE PCPN ONSET. SINCE NRN MD HAS A SOLID
SNOWPACK...THINK THE NAM IS ONTO SOMETHING...AND PREFER ITS SOLN FOR
THE MRNG. WE HV A FZRA ADVY IN PLACE FOR NRN MD...AND WL BE KEEPING
THAT GOING. ONLY CONCERN IS WHETHER THE NRN PORTION OF THE ERN WVA
PANHNDL /MINERAL TO JEFFERSON CNTYS/ SHUD BE INCLUDED. GRIDS FM 00Z
NAM/GMOS BLENDED IN FCST DATABASE. MUST ADMIT ITS A CLOSE CALL...
BUT SIGNS POINT TO JUST SQUEAKING IT OUT. WL MONITOR CLOSELY...BUT
HV OPTED TO NOT EXPAND CVRG ATTM.
CDFNT CROSSES CWFA DURING THE AFTN HRS...W/ STRONG CAA /AND DP
MIXING/ IN ITS WAKE. AM XPCTG A BRZY AFTN CONSIDERING WNDS AVBL BTWN
H8 AND SFC. WENT ON THE RESERVED SIDE IN DATABASE...KEEPING GUSTS
20-30 MPH. IF FULL MIXING TRANSPIRES...IT MAY BE MORE THAN THAT.
PAST FEW DAYS...TEMPS HV BEEN WARMER THAN PROGGED. SINCE CAA WL BE
ARRIVING LT IN THE DAY...AND WL BE ACCMPNYD BY COMPRESSIONAL
WARMING...WENT ON THE WARM SIDE OF GDNC FOR MAXT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
RDGG /SFC-H7/ WL BUILD ATOP CWFA TNGT...AND PROGRESS TO THE DELMARVA
THU MRNG. AM XPCTG MOCLR SKIES/DIMINISHING WNDS TNGT...AND MIN-T
FLLW SUIT.
BY THU...WL BE BACK IN RTN FLOW...AND SHUD HV A MID DECK CLDS
OVERSPREADING AREA ONCE AGN. THESE CLDS WL THICKEN THRUT THE DAY AS
ISENT LIFT STRENGTHENS. WHILE SOME MDL FIELDS SUGGEST THERE MAY BE A
LTL PCPN BY THE END OF THE DAY...POPS REMAIN VERY LOW. HV
ENTERTAINED A SCHC IN THE NWRN CORNER OF CWFA ONLY...WHICH WUD BE
NEARER A DVLPG WMFNT.
A LTL VARIANCE NOTED IN THU MAXT...BUT ALL GDNC WARMER THAN PRVS
FCST. HV RAISED TEMPS ACCRDGLY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY EVENING BEGINS WITH A WARM FRONT LOCATED TO THE SOUTH OF
THE AREA...BUT MODELS SHOW A STRENGTHENING LOW LEVEL JET AND
SOUTHERLY BOUNDARY LAYER WINDS LOOK STRONG ENOUGH TO SEND THIS WARM
FRONT NORTHWARD DURING THE NIGHT THURSDAY. SOME RAIN AND FOG ARE
POSSIBLE THURSDAY NIGHT...BUT AS QUICKLY AS THE WARM FRONT LIFTS
TO THE NORTH A COLD FRONT WILL BE APPROACHING FROM THE WEST.
MODELS/ENSEMBLES HAVE TRENDED FASTER...WITH SHOWERS MOVING INTO THE
POTOMAC HIGHLANDS LATE THURSDAY NIGHT AND THEN AFFECTING THE CWA
PRIMARILY FRIDAY MORNING AND EXITING DURING THE AFTERNOON. A FASTER
PASSAGE MAY HELP LIMIT INSTABILITY AND WIDESPREAD SEVERE...HOWEVER
STRONG WINDS IN THE LOW LEVELS MAY BE TRANSPORTED DOWN TO THE
SURFACE EVEN IN ABSENCE OF THUNDERSTORMS /I.E. WITH ONLY SHOWERS/
AND THUS LOCALLY DAMAGING WINDS WILL BE POSSIBLE IN A HIGH SHEAR
BUT LOW/LITTLE CAPE ENVIRONMENT.
MAXIMA MAY WIND UP OCCURRING DURING FRIDAY MORNING...WITH
TEMPERATURES DROPPING BEHIND THE FRONT LATER FRIDAY. ATTEMPTED TO
REFLECT SOME TIMING DETAILS IN THE GRIDS...INCLUDING FOR
MINIMA/MAXIMA THURSDAY NIGHT/FRIDAY.
DRIER AIR MOVES IN FOR FRIDAY NIGHT AND SATURDAY AND THUS THE RETURN
OF SUNSHINE IS EXPECTED FOR SATURDAY. WITH GOOD INSOLATION AND A
SOUTHWEST FLOW...SATURDAY LOOKS LIKE A MILD DAY WITH MAXIMA 10 PLUS
DEGREES ABOVE AVERAGE.
A REINFORCING COLD FRONT IS EXPECTED ON SUNDAY. ASIDE FROM SOME
CLOUDS AND SILENT POPS OVER THE HIGHLANDS...FRONT LIKELY PASSES
THROUGH RATHER QUIETLY. HIGH PRESSURE BUILDING IN BEHIND THE FRONT
WILL HOWEVER HAVE SOME COOLER AIR WITH IT /NEAR AVERAGE FOR THIS
TIME OF THE YEAR/ WHICH WILL TAKE HOLD OF THE MID-ATLANTIC EARLY
NEXT WEEK.
NEXT STORM SYSTEM APPROACHES ON TUESDAY...AND HAVE BUMPED POPS UP TO
CHANCE. UNCERTAINTY IN P-TYPE EXISTS AND HAVE GENERIC RAIN OR SNOW
WORDING.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDS ATTM..BUT XPCT PCPN TO OVERSPREAD TERMINALS DURING THE
MRNG PUSH. FLGT RESTRICTIONS MAY DVLP...BUT DO NOT XPCT MUCH WORSE
THAN MVFR. TEMPS SHUD BE WARM ENUF BY THE TIME PCPN ARRIVES /11-13
UTC/ FOR NO PTYPE CONCERNS--XPCT JUST RAIN. THE CLOSEST CALL WL BE
AT MRB AND MTN...WHERE THERE IS A CHC AT BRIEF FZRA AT ONSET. PCPN
DRIVEN BY A STRONG LLJ...AND HV LLWS CONDS IN TAFS THRU THE MRNG /UP
TO 45 KT/.
PCPN SHUD BE GONE BY MIDDAY...AND A WSHFT DURING THE AFTN WL
ACCOMPANY A CDFNT. WLY WNDS G25KT LKLY POST FROPA...BUT GRADIENT
/AND WNDS/ WL RELAX AFDK.
HIPRES OVNGT WL NO CIGS AND LTL WND. SLY FLOW WL RESUME THU MRNG...
INCRSG AGN DURING THE AFTN. CIGS WL DVLP AND LWR...BUT SHUD REMAIN
DRY THRU THE DAY W/ VFR CONDS PREVAILING.
THURSDAY NIGHT...FLIGHT RESTRICTIONS MAY DEVELOP IN SOME RAIN/FOG.
SREFS SUGGESTS AT LEAST IFR...WITH SUPPORT FROM MAV/MET. STRONG LLJ
WILL ALSO BRING THE LIKELIHOOD OF LOW LEVEL WIND SHEAR.
FRIDAY...COLD FRONT MOVES ACROSS THE AREA WITH SHOWERS. SHOWERS
COULD TRANSPORT STRONG GUSTY WINDS TO THE SURFACE. FROPA MAY WIND UP
BEING IN THE MORNING...ALTHOUGH EXACT TIMING IS STILL SOMEWHAT
UNCERTAIN.
SATURDAY INTO EARLY NEXT WEEK...HIGH PRESSURE BUILDS IN FOR NO
SIGNIFICANT WEATHER THROUGH MONDAY. NEXT STORM APPROACHES WITH A
CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
WHILE QUIET CONDS PREVAIL ON THE WATERS ATTM SLY WNDS AOB 10 KT/...
WNDS WL INCRS TDA AHD OF CDFNT. A STRONG SLY LLJ WL DVLP THIS MRNG.
WHILE THERE WL BE A STRONG INVSN WHICH WL TRAP MOST OF THE WNDS OFF
THE WATERS SFC...THE MAGNITUDE OF WND AND PRESENCE OF RA MAY MIX A
LTL DOWN. HV OPTED TO KEEP SCA GOING FOR MID BAY AND LWR PTMC...
ALTHO ITS NOT OF THE HIEST CONFIDENCE.
POST FROPA THERE IS A GOOD MIXED PROFILE FOR A FEW HRS. SCA IN
EFFECT FOR ALL WATERS TAFTN. THE CFP MAY BE A LTL LATER THAN PRVSLY
PROGGED...AND HV XTNDD SCA FOR THE WATERS INTO ELY EVNG PTMC AND MID
EVNG LWR PTMC/BAY.
GRADIENT WL RELAX OVNGT UNDER HIPRES. SLY FLOW WL RESUME THU. WHILE
GRADIENT INCREASES ONCE AGN...THINK THAT MIXING WL HOLD OFF...AND HV
KEPT WNDS UNDER SCA THRESHOLDS.
STRONG SOUTHERLY JET WILL BE IN PLACE THURSDAY NIGHT. A FRACTION OF
WIND ALOFT WILL LIKELY BE ABLE TO MIX DOWN OVERNIGHT FOR SCA
CONDITIONS. WINDS INCREASE FURTHER FRIDAY MORNING AHEAD OF A COLD
FRONT...POSSIBLY NEAR GALES. SHOWERS ASSOCIATED WITH THE FRONT MAY
ALSO BRING DOWN STRONG GUSTY WINDS. FRONT SHOULD MOVE EAST OF THE
WATERS FRIDAY AFTERNOON. HIGH PRESSURE BUILDS IN OVER THE WEEKEND.
&&
.HYDROLOGY...
WILL BE WATCHING SNOWMELT THIS WEEK AS THE WARMUP ENSUES. SNOW WATER
EQUIVALENT VALUES RANGE FROM LESS THAN AN INCH ALONG AND EAST OF
INTERSTATE 95 TO MORE THAN TWO INCHES WEST OF THE BLUE RIDGE AND
ALONG THE MASON DIXON LINE. OBSERVED SNOW WATER EQUIVALENT IS AROUND
4 INCHES IN THE POTOMAC HIGHLANDS /BUT THE HIGHEST VALUES ARE MAINLY
UPSTREAM OF JENNINGS RANDOLPH AND SAVAGE RIVER LAKES/.
A GRADUAL MELT IS EXPECTED IN THE COMING DAYS...SLIGHTLY MORE
PRONOUNCED THU INTO FRI AS LOWS STAY ABOVE FREEZING THURSDAY NIGHT.
IF MODERATE TO HEAVY PRECIPITATION OCCURRED COINCIDENT WITH THE
MELT...CONCERN WOULD BE HIGH FOR FLOODING. HOWEVER...AT THIS TIME...
RAIN AMOUNTS THROUGH FRIDAY ARE EXPECTED TO BE A HALF INCH OR LESS.
AT THIS TIME THE MOST LIKELY SCENARIO SEEMS TO BE A STEADY
WITHIN-BANK RISE OF STREAMS AND RIVERS LATE THIS WEEK AND INTO THE
WEEKEND. IF RAIN AND/OR SNOWMELT ARE MORE THAN CURRENTLY EXPECTED...
THE FLOOD THREAT WOULD INCREASE ACCORDINGLY FRIDAY AND SATURDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MDZ003>007-009-010-501-502.
VA...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
VAZ025>031-040-042-052-501-503-504.
WV...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
WVZ050>053-055-501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR ANZ530-531-538-539.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 8 PM EST THIS
EVENING FOR ANZ535-536.
&&
$$
SYNOPSIS...BPP
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...BPP
AVIATION...HTS/BPP
MARINE...HTS/BPP
HYDROLOGY...JCE
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
510 AM EST WED FEB 19 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA TODAY. HIGH PRESSURE WILL RETURN
TONIGHT AND THEN DRIFT OFFSHORE THURSDAY. A STRONGER COLD FRONT
MOVES THROUGH FRIDAY. HIGH PRESSURE WILL THEN RETURN OVER THE
WEEKEND. LOW PRESSURE APPROACHES THE REGION TUESDAY OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDT...
06Z NAM COME IN JUST AS COLD AS THE 00Z RUN. IN ADDITION...REPORTS
FM UPSTREAM SUGGEST ICING OCCURRING EVEN WHERE SFC TEMPS ABV FRZG
DUE TO COLD GRND. THEREFORE...HV ADDED ENTIRE ERN WV PNHNDL TO
FZRA ADVY. LEFT HIGHLAND CO VA OUT DUE TO SFC TEMP AT HSP IN THE
40S. IN ADDITION...LEFT CENTRAL SHEN VLY OUT IN SPITE OF COLD
TEMPS AS PRECIP THERE NOT IMMINENT...AND NO HIER THAN CHC. LOOKING
AT RDR LOOP THAT MAKES SENSE...SINCE THERE/S A GAP BTWN THE
PREFRNTL RAIN TO THE W AND THE LEADING EDGE OF THE LLJ TO THE S.
FINALLY... HV RESTRUCTURED END TIME TO FIT EVOLUTION. WARMTH FM
ALOFT SHUD ENCOMPASS RDGS OF THE PTMC HIGHLANDS...AND HV ENDING
TIME THERE A CPL HRS ERLR THAN CENTRAL-NERN MD.
WL STILL NEED TO MONITOR EDGE OF LOUDOUN-MONTCO-HOWARD CNTYS.
JYO/GAI BOTH ABV FRZG. THINK PCPN WL MAKE IT INTO BURBS BY 12-13
UTC. AM HOPING THAT GRND CAN WARM A PINCH AFTER DAYLIGHT. SFC
TEMPS ALREADY ABV FRZG.
OTRW...THOUGHT PROCESS SAME AS BEFORE...AS DETAILED IN THE PREV
DSCN...WHICH FLLWS...
LOPRES OVER LK SUPERIOR ELY THIS MRNG...W/ AN ATTENDENT CDFNT FM
ORD DOWN THE MID-LWR MS RVR VLY. SFC ANALY ALSO SUGGESTING THERE
MAY BE A HINT OF A WMFNT ACRS CWFA...ROUGHLY DOWN THE PTMC. THE
CORE OF THE COLD AIR /TEMPS IN THE TEENS/ IS OVER NEW
ENGLAND...BUT SUBFRZG AIR CAN BE FOUND IN THE PTMC HIGHLANDS AND
ACRS NRN MD. MEANWHILE... STRONG ISENT LIFT IS PRODUCING AN AREA
OF PCPN IN THE OH/TN VLYS AND ACRS THE MTNS OF NC. THAT LIFT...AND
THE ASSOC PCPN /WHICH IS ALL RA/...PROGGED TO ARRIVE IN THE CWFA
BTWN 12-14 UTC. HV INCRSD POPS AND DELAYED TIMING BASED ON LTST
GDNC. QSTN REMAINS WHAT WL THE SFC TEMPS BE WHEN RAIN ARRIVES.
MDL SNDGS...SPCLY FM THE NAM...SUGGEST THAT A STRONG WARM NOSE WL
RESIDE ARND H9 BUT SFC TEMPS WL STILL BE BLO FRZG. GFS IS WARMER AT
THE SFC AND HAS A LESS PRONOUNCED WARM AIR INTRUSION. RAP BTWN THE
TWO THERMALLY...BUT HAS A LATE PCPN ONSET. SINCE NRN MD HAS A SOLID
SNOWPACK...THINK THE NAM IS ONTO SOMETHING...AND PREFER ITS SOLN FOR
THE MRNG. WE HV A FZRA ADVY IN PLACE FOR NRN MD...AND WL BE KEEPING
THAT GOING. ONLY CONCERN IS WHETHER THE NRN PORTION OF THE ERN WVA
PANHNDL /MINERAL TO JEFFERSON CNTYS/ SHUD BE INCLUDED. GRIDS FM 00Z
NAM/GMOS BLENDED IN FCST DATABASE. MUST ADMIT ITS A CLOSE CALL...
BUT SIGNS POINT TO JUST SQUEAKING IT OUT. WL MONITOR CLOSELY...BUT
HV OPTED TO NOT EXPAND CVRG ATTM.
CDFNT CROSSES CWFA DURING THE AFTN HRS...W/ STRONG CAA /AND DP
MIXING/ IN ITS WAKE. AM XPCTG A BRZY AFTN CONSIDERING WNDS AVBL BTWN
H8 AND SFC. WENT ON THE RESERVED SIDE IN DATABASE...KEEPING GUSTS
20-30 MPH. IF FULL MIXING TRANSPIRES...IT MAY BE MORE THAN THAT.
PAST FEW DAYS...TEMPS HV BEEN WARMER THAN PROGGED. SINCE CAA WL BE
ARRIVING LT IN THE DAY...AND WL BE ACCMPNYD BY COMPRESSIONAL
WARMING...WENT ON THE WARM SIDE OF GDNC FOR MAXT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
RDGG /SFC-H7/ WL BUILD ATOP CWFA TNGT...AND PROGRESS TO THE DELMARVA
THU MRNG. AM XPCTG MOCLR SKIES/DIMINISHING WNDS TNGT...AND MIN-T
FLLW SUIT.
BY THU...WL BE BACK IN RTN FLOW...AND SHUD HV A MID DECK CLDS
OVERSPREADING AREA ONCE AGN. THESE CLDS WL THICKEN THRUT THE DAY AS
ISENT LIFT STRENGTHENS. WHILE SOME MDL FIELDS SUGGEST THERE MAY BE A
LTL PCPN BY THE END OF THE DAY...POPS REMAIN VERY LOW. HV
ENTERTAINED A SCHC IN THE NWRN CORNER OF CWFA ONLY...WHICH WUD BE
NEARER A DVLPG WMFNT.
A LTL VARIANCE NOTED IN THU MAXT...BUT ALL GDNC WARMER THAN PRVS
FCST. HV RAISED TEMPS ACCRDGLY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY EVENING BEGINS WITH A WARM FRONT LOCATED TO THE SOUTH OF
THE AREA...BUT MODELS SHOW A STRENGTHENING LOW LEVEL JET AND
SOUTHERLY BOUNDARY LAYER WINDS LOOK STRONG ENOUGH TO SEND THIS WARM
FRONT NORTHWARD DURING THE NIGHT THURSDAY. SOME RAIN AND FOG ARE
POSSIBLE THURSDAY NIGHT...BUT AS QUICKLY AS THE WARM FRONT LIFTS
TO THE NORTH A COLD FRONT WILL BE APPROACHING FROM THE WEST.
MODELS/ENSEMBLES HAVE TRENDED FASTER...WITH SHOWERS MOVING INTO THE
POTOMAC HIGHLANDS LATE THURSDAY NIGHT AND THEN AFFECTING THE CWA
PRIMARILY FRIDAY MORNING AND EXITING DURING THE AFTERNOON. A FASTER
PASSAGE MAY HELP LIMIT INSTABILITY AND WIDESPREAD SEVERE...HOWEVER
STRONG WINDS IN THE LOW LEVELS MAY BE TRANSPORTED DOWN TO THE
SURFACE EVEN IN ABSENCE OF THUNDERSTORMS /I.E. WITH ONLY SHOWERS/
AND THUS LOCALLY DAMAGING WINDS WILL BE POSSIBLE IN A HIGH SHEAR
BUT LOW/LITTLE CAPE ENVIRONMENT.
MAXIMA MAY WIND UP OCCURRING DURING FRIDAY MORNING...WITH
TEMPERATURES DROPPING BEHIND THE FRONT LATER FRIDAY. ATTEMPTED TO
REFLECT SOME TIMING DETAILS IN THE GRIDS...INCLUDING FOR
MINIMA/MAXIMA THURSDAY NIGHT/FRIDAY.
DRIER AIR MOVES IN FOR FRIDAY NIGHT AND SATURDAY AND THUS THE RETURN
OF SUNSHINE IS EXPECTED FOR SATURDAY. WITH GOOD INSOLATION AND A
SOUTHWEST FLOW...SATURDAY LOOKS LIKE A MILD DAY WITH MAXIMA 10 PLUS
DEGREES ABOVE AVERAGE.
A REINFORCING COLD FRONT IS EXPECTED ON SUNDAY. ASIDE FROM SOME
CLOUDS AND SILENT POPS OVER THE HIGHLANDS...FRONT LIKELY PASSES
THROUGH RATHER QUIETLY. HIGH PRESSURE BUILDING IN BEHIND THE FRONT
WILL HOWEVER HAVE SOME COOLER AIR WITH IT /NEAR AVERAGE FOR THIS
TIME OF THE YEAR/ WHICH WILL TAKE HOLD OF THE MID-ATLANTIC EARLY
NEXT WEEK.
NEXT STORM SYSTEM APPROACHES ON TUESDAY...AND HAVE BUMPED POPS UP TO
CHANCE. UNCERTAINTY IN P-TYPE EXISTS AND HAVE GENERIC RAIN OR SNOW
WORDING.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDS ATTM..BUT XPCT PCPN TO OVERSPREAD TERMINALS DURING THE
MRNG PUSH. FLGT RESTRICTIONS MAY DVLP...BUT DO NOT XPCT MUCH WORSE
THAN MVFR. TEMPS SHUD BE WARM ENUF BY THE TIME PCPN ARRIVES /11-13
UTC/ FOR NO PTYPE CONCERNS--XPCT JUST RAIN. THE CLOSEST CALL WL BE
AT MRB AND MTN...WHERE THERE IS A CHC AT BRIEF FZRA AT ONSET. PCPN
DRIVEN BY A STRONG LLJ...AND HV LLWS CONDS IN TAFS THRU THE MRNG /UP
TO 45 KT/.
PCPN SHUD BE GONE BY MIDDAY...AND A WSHFT DURING THE AFTN WL
ACCOMPANY A CDFNT. WLY WNDS G25KT LKLY POST FROPA...BUT GRADIENT
/AND WNDS/ WL RELAX AFDK.
HIPRES OVNGT WL NO CIGS AND LTL WND. SLY FLOW WL RESUME THU MRNG...
INCRSG AGN DURING THE AFTN. CIGS WL DVLP AND LWR...BUT SHUD REMAIN
DRY THRU THE DAY W/ VFR CONDS PREVAILING.
THURSDAY NIGHT...FLIGHT RESTRICTIONS MAY DEVELOP IN SOME RAIN/FOG.
SREFS SUGGESTS AT LEAST IFR...WITH SUPPORT FROM MAV/MET. STRONG LLJ
WILL ALSO BRING THE LIKELIHOOD OF LOW LEVEL WIND SHEAR.
FRIDAY...COLD FRONT MOVES ACROSS THE AREA WITH SHOWERS. SHOWERS
COULD TRANSPORT STRONG GUSTY WINDS TO THE SURFACE. FROPA MAY WIND UP
BEING IN THE MORNING...ALTHOUGH EXACT TIMING IS STILL SOMEWHAT
UNCERTAIN.
SATURDAY INTO EARLY NEXT WEEK...HIGH PRESSURE BUILDS IN FOR NO
SIGNIFICANT WEATHER THROUGH MONDAY. NEXT STORM APPROACHES WITH A
CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
WHILE QUIET CONDS PREVAIL ON THE WATERS ATTM SLY WNDS AOB 10 KT/...
WNDS WL INCRS TDA AHD OF CDFNT. A STRONG SLY LLJ WL DVLP THIS MRNG.
WHILE THERE WL BE A STRONG INVSN WHICH WL TRAP MOST OF THE WNDS OFF
THE WATERS SFC...THE MAGNITUDE OF WND AND PRESENCE OF RA MAY MIX A
LTL DOWN. HV OPTED TO KEEP SCA GOING FOR MID BAY AND LWR PTMC...
ALTHO ITS NOT OF THE HIEST CONFIDENCE.
POST FROPA THERE IS A GOOD MIXED PROFILE FOR A FEW HRS. SCA IN
EFFECT FOR ALL WATERS TAFTN. THE CFP MAY BE A LTL LATER THAN PRVSLY
PROGGED...AND HV XTNDD SCA FOR THE WATERS INTO ELY EVNG PTMC AND MID
EVNG LWR PTMC/BAY.
GRADIENT WL RELAX OVNGT UNDER HIPRES. SLY FLOW WL RESUME THU. WHILE
GRADIENT INCREASES ONCE AGN...THINK THAT MIXING WL HOLD OFF...AND HV
KEPT WNDS UNDER SCA THRESHOLDS.
STRONG SOUTHERLY JET WILL BE IN PLACE THURSDAY NIGHT. A FRACTION OF
WIND ALOFT WILL LIKELY BE ABLE TO MIX DOWN OVERNIGHT FOR SCA
CONDITIONS. WINDS INCREASE FURTHER FRIDAY MORNING AHEAD OF A COLD
FRONT...POSSIBLY NEAR GALES. SHOWERS ASSOCIATED WITH THE FRONT MAY
ALSO BRING DOWN STRONG GUSTY WINDS. FRONT SHOULD MOVE EAST OF THE
WATERS FRIDAY AFTERNOON. HIGH PRESSURE BUILDS IN OVER THE WEEKEND.
&&
.HYDROLOGY...
WILL BE WATCHING SNOWMELT THIS WEEK AS THE WARMUP ENSUES. SNOW WATER
EQUIVALENT VALUES RANGE FROM LESS THAN AN INCH ALONG AND EAST OF
INTERSTATE 95 TO MORE THAN TWO INCHES WEST OF THE BLUE RIDGE AND
ALONG THE MASON DIXON LINE. OBSERVED SNOW WATER EQUIVALENT IS AROUND
4 INCHES IN THE POTOMAC HIGHLANDS /BUT THE HIGHEST VALUES ARE MAINLY
UPSTREAM OF JENNINGS RANDOLPH AND SAVAGE RIVER LAKES/.
A GRADUAL MELT IS EXPECTED IN THE COMING DAYS...SLIGHTLY MORE
PRONOUNCED THU INTO FRI AS LOWS STAY ABOVE FREEZING THURSDAY NIGHT.
IF MODERATE TO HEAVY PRECIPITATION OCCURRED COINCIDENT WITH THE
MELT...CONCERN WOULD BE HIGH FOR FLOODING. HOWEVER...AT THIS TIME...
RAIN AMOUNTS THROUGH FRIDAY ARE EXPECTED TO BE A HALF INCH OR LESS.
AT THIS TIME THE MOST LIKELY SCENARIO SEEMS TO BE A STEADY
WITHIN-BANK RISE OF STREAMS AND RIVERS LATE THIS WEEK AND INTO THE
WEEKEND. IF RAIN AND/OR SNOWMELT ARE MORE THAN CURRENTLY EXPECTED...
THE FLOOD THREAT WOULD INCREASE ACCORDINGLY FRIDAY AND SATURDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FREEZING RAIN ADVISORY UNTIL 8 AM EST THIS MORNING FOR MDZ501-
502.
FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MDZ003>007.
VA...NONE.
WV...FREEZING RAIN ADVISORY UNTIL 8 AM EST THIS MORNING FOR WVZ050-
055-501>506.
FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
WVZ051>053.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR ANZ530-531-538-539.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 8 PM EST THIS
EVENING FOR ANZ535-536.
&&
$$
SYNOPSIS...BPP
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...BPP
AVIATION...HTS/BPP
MARINE...HTS/BPP
HYDROLOGY...JCE
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
355 AM EST WED FEB 19 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA TODAY. HIGH PRESSURE WILL RETURN
TONIGHT AND THEN DRIFT OFFSHORE THURSDAY. A STRONGER COLD FRONT
MOVES THROUGH FRIDAY. HIGH PRESSURE WILL THEN RETURN OVER THE
WEEKEND. LOW PRESSURE APPROACHES THE REGION TUESDAY OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOPRES OVER LK SUPERIOR ELY THIS MRNG...W/ AN ATTENDENT CDFNT FM ORD
DOWN THE MID-LWR MS RVR VLY. SFC ANALY ALSO SUGGESTING THERE MAY BE
A HINT OF A WMFNT ACRS CWFA...ROUGHLY DOWN THE PTMC. THE CORE OF THE
COLD AIR /TEMPS IN THE TEENS/ IS OVER NEW ENGLAND...BUT SUBFRZG AIR
CAN BE FOUND IN THE PTMC HIGHLANDS AND ACRS NRN MD. MEANWHILE...
STRONG ISENT LIFT IS PRODUCING AN AREA OF PCPN IN THE OH/TN VLYS AND
ACRS THE MTNS OF NC. THAT LIFT...AND THE ASSOC PCPN /WHICH IS ALL
RA/...PROGGED TO ARRIVE IN THE CWFA BTWN 12-14 UTC. HV INCRSD POPS
AND DELAYED TIMING BASED ON LTST GDNC. QSTN REMAINS WHAT WL THE SFC
TEMPS BE WHEN RAIN ARRIVES.
MDL SNDGS...SPCLY FM THE NAM...SUGGEST THAT A STRONG WARM NOSE WL
RESIDE ARND H9 BUT SFC TEMPS WL STILL BE BLO FRZG. GFS IS WARMER AT
THE SFC AND HAS A LESS PRONOUNCED WARM AIR INTRUSION. RAP BTWN THE
TWO THERMALLY...BUT HAS A LATE PCPN ONSET. SINCE NRN MD HAS A SOLID
SNOWPACK...THINK THE NAM IS ONTO SOMETHING...AND PREFER ITS SOLN FOR
THE MRNG. WE HV A FZRA ADVY IN PLACE FOR NRN MD...AND WL BE KEEPING
THAT GOING. ONLY CONCERN IS WHETHER THE NRN PORTION OF THE ERN WVA
PANHNDL /MINERAL TO JEFFERSON CNTYS/ SHUD BE INCLUDED. GRIDS FM 00Z
NAM/GMOS BLENDED IN FCST DATABASE. MUST ADMIT ITS A CLOSE CALL...
BUT SIGNS POINT TO JUST SQUEAKING IT OUT. WL MONITOR CLOSELY...BUT
HV OPTED TO NOT EXPAND CVRG ATTM.
CDFNT CROSSES CWFA DURING THE AFTN HRS...W/ STRONG CAA /AND DP
MIXING/ IN ITS WAKE. AM XPCTG A BRZY AFTN CONSIDERING WNDS AVBL BTWN
H8 AND SFC. WENT ON THE RESERVED SIDE IN DATABASE...KEEPING GUSTS
20-30 MPH. IF FULL MIXING TRANSPIRES...IT MAY BE MORE THAN THAT.
PAST FEW DAYS...TEMPS HV BEEN WARMER THAN PROGGED. SINCE CAA WL BE
ARRIVING LT IN THE DAY...AND WL BE ACCMPNYD BY COMPRESSIONAL
WARMING...WENT ON THE WARM SIDE OF GDNC FOR MAXT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
RDGG /SFC-H7/ WL BUILD ATOP CWFA TNGT...AND PROGRESS TO THE DELMARVA
THU MRNG. AM XPCTG MOCLR SKIES/DIMINISHING WNDS TNGT...AND MIN-T
FLLW SUIT.
BY THU...WL BE BACK IN RTN FLOW...AND SHUD HV A MID DECK CLDS
OVERSPREADING AREA ONCE AGN. THESE CLDS WL THICKEN THRUT THE DAY AS
ISENT LIFT STRENGTHENS. WHILE SOME MDL FIELDS SUGGEST THERE MAY BE A
LTL PCPN BY THE END OF THE DAY...POPS REMAIN VERY LOW. HV
ENTERTAINED A SCHC IN THE NWRN CORNER OF CWFA ONLY...WHICH WUD BE
NEARER A DVLPG WMFNT.
A LTL VARIANCE NOTED IN THU MAXT...BUT ALL GDNC WARMER THAN PRVS
FCST. HV RAISED TEMPS ACCRDGLY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY EVENING BEGINS WITH A WARM FRONT LOCATED TO THE SOUTH OF
THE AREA...BUT MODELS SHOW A STRENGTHENING LOW LEVEL JET AND
SOUTHERLY BOUNDARY LAYER WINDS LOOK STRONG ENOUGH TO SEND THIS WARM
FRONT NORTHWARD DURING THE NIGHT THURSDAY. SOME RAIN AND FOG ARE
POSSIBLE THURSDAY NIGHT...BUT AS QUICKLY AS THE WARM FRONT LIFTS
TO THE NORTH A COLD FRONT WILL BE APPROACHING FROM THE WEST.
MODELS/ENSEMBLES HAVE TRENDED FASTER...WITH SHOWERS MOVING INTO THE
POTOMAC HIGHLANDS LATE THURSDAY NIGHT AND THEN AFFECTING THE CWA
PRIMARILY FRIDAY MORNING AND EXITING DURING THE AFTERNOON. A FASTER
PASSAGE MAY HELP LIMIT INSTABILITY AND WIDESPREAD SEVERE...HOWEVER
STRONG WINDS IN THE LOW LEVELS MAY BE TRANSPORTED DOWN TO THE
SURFACE EVEN IN ABSENCE OF THUNDERSTORMS /I.E. WITH ONLY SHOWERS/
AND THUS LOCALLY DAMAGING WINDS WILL BE POSSIBLE IN A HIGH SHEAR
BUT LOW/LITTLE CAPE ENVIRONMENT.
MAXIMA MAY WIND UP OCCURRING DURING FRIDAY MORNING...WITH
TEMPERATURES DROPPING BEHIND THE FRONT LATER FRIDAY. ATTEMPTED TO
REFLECT SOME TIMING DETAILS IN THE GRIDS...INCLUDING FOR
MINIMA/MAXIMA THURSDAY NIGHT/FRIDAY.
DRIER AIR MOVES IN FOR FRIDAY NIGHT AND SATURDAY AND THUS THE RETURN
OF SUNSHINE IS EXPECTED FOR SATURDAY. WITH GOOD INSOLATION AND A
SOUTHWEST FLOW...SATURDAY LOOKS LIKE A MILD DAY WITH MAXIMA 10 PLUS
DEGREES ABOVE AVERAGE.
A REINFORCING COLD FRONT IS EXPECTED ON SUNDAY. ASIDE FROM SOME
CLOUDS AND SILENT POPS OVER THE HIGHLANDS...FRONT LIKELY PASSES
THROUGH RATHER QUIETLY. HIGH PRESSURE BUILDING IN BEHIND THE FRONT
WILL HOWEVER HAVE SOME COOLER AIR WITH IT /NEAR AVERAGE FOR THIS
TIME OF THE YEAR/ WHICH WILL TAKE HOLD OF THE MID-ATLANTIC EARLY
NEXT WEEK.
NEXT STORM SYSTEM APPROACHES ON TUESDAY...AND HAVE BUMPED POPS UP TO
CHANCE. UNCERTAINTY IN P-TYPE EXISTS AND HAVE GENERIC RAIN OR SNOW
WORDING.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDS ATTM..BUT XPCT PCPN TO OVERSPREAD TERMINALS DURING THE
MRNG PUSH. FLGT RESTRICTIONS MAY DVLP...BUT DO NOT XPCT MUCH WORSE
THAN MVFR. TEMPS SHUD BE WARM ENUF BY THE TIME PCPN ARRIVES /11-13
UTC/ FOR NO PTYPE CONCERNS--XPCT JUST RAIN. THE CLOSEST CALL WL BE
AT MRB AND MTN...WHERE THERE IS A CHC AT BRIEF FZRA AT ONSET. PCPN
DRIVEN BY A STRONG LLJ...AND HV LLWS CONDS IN TAFS THRU THE MRNG /UP
TO 45 KT/.
PCPN SHUD BE GONE BY MIDDAY...AND A WSHFT DURING THE AFTN WL
ACCOMPANY A CDFNT. WLY WNDS G25KT LKLY POST FROPA...BUT GRADIENT
/AND WNDS/ WL RELAX AFDK.
HIPRES OVNGT WL NO CIGS AND LTL WND. SLY FLOW WL RESUME THU MRNG...
INCRSG AGN DURING THE AFTN. CIGS WL DVLP AND LWR...BUT SHUD REMAIN
DRY THRU THE DAY W/ VFR CONDS PREVAILING.
THURSDAY NIGHT...FLIGHT RESTRICTIONS MAY DEVELOP IN SOME RAIN/FOG.
SREFS SUGGESTS AT LEAST IFR...WITH SUPPORT FROM MAV/MET. STRONG LLJ
WILL ALSO BRING THE LIKELIHOOD OF LOW LEVEL WIND SHEAR.
FRIDAY...COLD FRONT MOVES ACROSS THE AREA WITH SHOWERS. SHOWERS
COULD TRANSPORT STRONG GUSTY WINDS TO THE SURFACE. FROPA MAY WIND UP
BEING IN THE MORNING...ALTHOUGH EXACT TIMING IS STILL SOMEWHAT
UNCERTAIN.
SATURDAY INTO EARLY NEXT WEEK...HIGH PRESSURE BUILDS IN FOR NO
SIGNIFICANT WEATHER THROUGH MONDAY. NEXT STORM APPROACHES WITH A
CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
WHILE QUIET CONDS PREVAIL ON THE WATERS ATTM SLY WNDS AOB 10 KT/...
WNDS WL INCRS TDA AHD OF CDFNT. A STRONG SLY LLJ WL DVLP THIS MRNG.
WHILE THERE WL BE A STRONG INVSN WHICH WL TRAP MOST OF THE WNDS OFF
THE WATERS SFC...THE MAGNITUDE OF WND AND PRESENCE OF RA MAY MIX A
LTL DOWN. HV OPTED TO KEEP SCA GOING FOR MID BAY AND LWR PTMC...
ALTHO ITS NOT OF THE HIEST CONFIDENCE.
POST FROPA THERE IS A GOOD MIXED PROFILE FOR A FEW HRS. SCA IN
EFFECT FOR ALL WATERS TAFTN. THE CFP MAY BE A LTL LATER THAN PRVSLY
PROGGED...AND HV XTNDD SCA FOR THE WATERS INTO ELY EVNG PTMC AND MID
EVNG LWR PTMC/BAY.
GRADIENT WL RELAX OVNGT UNDER HIPRES. SLY FLOW WL RESUME THU. WHILE
GRADIENT INCREASES ONCE AGN...THINK THAT MIXING WL HOLD OFF...AND HV
KEPT WNDS UNDER SCA THRESHOLDS.
STRONG SOUTHERLY JET WILL BE IN PLACE THURSDAY NIGHT. A FRACTION OF
WIND ALOFT WILL LIKELY BE ABLE TO MIX DOWN OVERNIGHT FOR SCA
CONDITIONS. WINDS INCREASE FURTHER FRIDAY MORNING AHEAD OF A COLD
FRONT...POSSIBLY NEAR GALES. SHOWERS ASSOCIATED WITH THE FRONT MAY
ALSO BRING DOWN STRONG GUSTY WINDS. FRONT SHOULD MOVE EAST OF THE
WATERS FRIDAY AFTERNOON. HIGH PRESSURE BUILDS IN OVER THE WEEKEND.
&&
.HYDROLOGY...
WILL BE WATCHING SNOWMELT THIS WEEK AS THE WARMUP ENSUES. SNOW WATER
EQUIVALENT VALUES RANGE FROM LESS THAN AN INCH ALONG AND EAST OF
INTERSTATE 95 TO MORE THAN TWO INCHES WEST OF THE BLUE RIDGE AND
ALONG THE MASON DIXON LINE. OBSERVED SNOW WATER EQUIVALENT IS AROUND
4 INCHES IN THE POTOMAC HIGHLANDS /BUT THE HIGHEST VALUES ARE MAINLY
UPSTREAM OF JENNINGS RANDOLPH AND SAVAGE RIVER LAKES/.
A GRADUAL MELT IS EXPECTED IN THE COMING DAYS...SLIGHTLY MORE
PRONOUNCED THU INTO FRI AS LOWS STAY ABOVE FREEZING THURSDAY NIGHT.
IF MODERATE TO HEAVY PRECIPITATION OCCURRED COINCIDENT WITH THE
MELT...CONCERN WOULD BE HIGH FOR FLOODING. HOWEVER...AT THIS TIME...
RAIN AMOUNTS THROUGH FRIDAY ARE EXPECTED TO BE A HALF INCH OR LESS.
AT THIS TIME THE MOST LIKELY SCENARIO SEEMS TO BE A STEADY
WITHIN-BANK RISE OF STREAMS AND RIVERS LATE THIS WEEK AND INTO THE
WEEKEND. IF RAIN AND/OR SNOWMELT ARE MORE THAN CURRENTLY EXPECTED...
THE FLOOD THREAT WOULD INCREASE ACCORDINGLY FRIDAY AND SATURDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MDZ003>007-501-502.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR ANZ530-531-538-539.
SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 8 PM EST THIS
EVENING FOR ANZ535-536.
&&
$$
SYNOPSIS...BPP
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...BPP
AVIATION...HTS/BPP
MARINE...HTS/BPP
HYDROLOGY...JCE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
519 PM EST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF MOVING ACROSS THE
ROCKIES WITH 2 MAIN SHORTWAVES OF INTEREST THAT WILL CONSPIRE TO
BRING A STRONG WINTER STORM TO THE UPPER LAKES. ONE IS OVER SRN
SASKATCHEWAN/MT AND THE OTHER IS MOVING ACROSS NV/UT. WELL OUT AHEAD
OF THESE FEATURES...A QUIET NIGHT IS EXPECTED ACROSS THE FCST AREA.
MAINLY CLEAR SKIES INITIALLY WILL GIVE WAY TO INCREASING HIGH AND
MID CLOUDS DURING THE NIGHT. LIGHT WINDS AND LACK OF SIGNIFICANT
CLOUD COVER EARLY SHOULD ALLOW TEMPS OVER THE CNTRL AND E TO FALL
QUICKLY. LEANED TOWARD SOME OF THE COLDER GUIDANCE WITH MINS IN THE
MID TEENS IN THE INTERIOR. OUT W...DEVELOPING LIGHT SOUTHERLY FLOW
AND A QUICKER INCREASE IN CLOUDS SHOULD HOLD TEMPS UP INTO THE
LOW/MID 20S.
ON THU...LOW PRES ORGANIZING OVER THE SRN PLAINS EARLY IN THE MORNING
WILL LIFT NE INTO THE MID MISSISSIPPI VALLEY DURING THE AFTN.
GENERAL MODEL TREND IN THE LAST DAY OR SO HAS BEEN FOR A SLOWER
EXPANSION OF PCPN NE INTO THE UPPER LAKES AS SYSTEM IS TENDING TO
START THE RAPID DEEPENING PHASE MORE QUICKLY BEFORE REACHING THE
UPPER LAKES. OPTED TO FOLLOW THIS TREND AND FAVOR THE SLOWER
SOLUTIONS. AS A RESULT...PCPN ONSET HAS BEEN PUSHED BACK SOME. MAIN
PUSH OF HEAVY PCPN IS NOT EXPECTED UNTIL THU NIGHT WHEN IT WILL
RAPIDLY SPREAD ACROSS THE AREA. INITIALLY...EVAPORATIVE/ADIABATIC
COOLING SHOULD LEAD TO PTYPE AS MAINLY SNOW...BUT DID INCLUDE SOME
MENTION OF MIXED PTYPES OVER ABOUT THE SE HALF.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
MAIN CONCERN FOR THE LONG TERM FORECAST IS THE WINTER STORM EXPECTED
ON THURSDAY NIGHT AND FRIDAY.
EARLIER MODEL RUNS HAVE CONSISTENTLY KEPT THE TWO SURFACE LOWS
CROSSING FROM ILLINOIS AND MINNESOTA THURSDAY AFTERNOON TO A MERGED
LOW OVER CENTRAL UPPER MICHIGAN BY LATE THURSDAY EVENING. THIS
BRINGS WARM AIR AND HENCE MIXED PRECIPITATION INTO PORTIONS OF
CENTRAL AND EASTERN UPPER MICHIGAN. CONCERNS THIS PAST FEW DAYS HAVE
BEEN ABOUT THE FORECASTED LOW TRACK SHIFTING AS THE MODELS HAD NOT
REALLY BEEN ABLE TO ADEQUATELY SAMPLE THE SYSTEM UP UNTIL TODAY.
HOWEVER...NOW THAT THE LOW PRESSURE TROUGH RESPONSIBLE FOR THE
DEVELOPMENT OF THIS SYSTEM HAS MOVED ONSHORE IN THE PACIFIC
NORTHWEST...DIFFERENCES IN THE MODELS HAVE DEVELOPED. THE 6Z NAM
BEGAN TRENDING THE SYSTEM EASTWARD...AND THE 12Z NAM HAS COMPLETELY
MOVED THE LOW PRESSURE CENTER LATE THURSDAY EVENING FROM THE CENTRAL
U.P. TO OVER NORTHERN LAKE MICHIGAN. IT IS ALSO SLOWER THAN THE
OTHER SOLUTIONS. FURTHER COMPLICATING MATTERS...THE 12Z GEM MOVED
THE LOW PRESSURE CENTER FURTHER WEST OVER NORTH CENTRAL UPPER
MICHIGAN. THE 12Z GFS HOWEVER...HAS TRENDED SLIGHTLY WESTWARD FROM
ITS 6Z SOLUTION. THIS PUTS THE LOW OVER WESTERN UPPER MI BY 6Z
FRIDAY.
OVERALL...FURTHER EAST SOLUTIONS DIMINISH MIXED PRECIPITATION
CONCERNS AND PULL THE HEAVIEST CORE OF SNOW FURTHER EAST...WHEREAS
PREVIOUS FCST HAD IT MAINLY OVER THE WEST. FOR THIS
FORECAST...DECIDED TO LEAN TOWARDS THE WESTERN SOLUTIONS AS THIS HAS
BEEN THE MORE PERSISTENT SOLUTION. STARTED TRENDING SLIGHTLY MORE
WESTWARD WITH THE FORECAST GRIDS AS A RESULT...NAMELY THE
GFS/GEM/ECMWF COMPROMISE. AS FAR AS TIMING GOES...THE GEM BRINGS
THINGS IN SLOWER. THE 00Z ECMWF/12Z GFS BRING THE LOW THROUGH
QUICKER BY ABOUT 6 HRS...WITH THE CENTER OVER NORTH CENTRAL UPPER MI
BY 6Z FRIDAY. THE GEM IS STILL OVER CENTRAL WI AT THIS TIME.
PREVIOUS RUNS OF THE GEM HAD TIMING MORE LIKE THAT OF THE RECENT
RUNS OF THE ECMWF/GFS...THOUGH THE GFS TENDS TO BE MORE PROGRESSIVE
WITH SYSTEMS. WILL GO MIDDLE OF THE ROAD FOR NOW TO COMPENSATE FOR
THIS.
THE GFS/GEM/ECMWF BLEND SHOWS A BROAD AREA OF ISENTROPIC ASCENT
OVERSPREADING THE AREA STARTING THURSDAY AFTERNOON...WITH THE
STRONGEST MOISTURE TRANSPORT FROM THE 18Z THUR-06Z FRI TIME FRAME
OVER LOWER MICHIGAN...NORTHERN WI...AND CENTRAL/EASTERN UPPER
MICHIGAN. 700/850MB FGEN BAND MOVES FROM ROUGHLY SOUTH TO NORTH
ACROSS THE AREA BEGINNING AROUND THIS TIME AND CONTINUING THROUGH AS
SYSTEM DEEPENS WITH NEGATIVELY TILTING UPPER TROUGH. THE SYSTEM
BEGINS TO OCCLUDE...AND THE TROWAL DEVELOPS AND POSITIONS ITSELF/AND
THE ASSOCIATED FGEN BAND OVER WESTERN UPPER MI.
AS FAR AS PTYPE GOES...THERE ARE DIFFERENCES BETWEEN THE 12Z GFS/12Z
GEM/00Z ECMWF WITH REGARDS TO THE HEIGHT/TEMP OF THE WARMEST LAYER
ALOFT AND DEPTH OF THE SURFACE COLD LAYER FROM 00-03Z FRI...AND THE
SURFACE WARM LAYER AROUND 6-9Z FRI. BY 12Z FRIDAY THE MODELS ARE
CONSISTENT IN HAVING THE WHOLE SOUNDING BELOW ZERO.
IT LOOKS LIKE THE EASTERN HALF WILL SEE THE BEST SHOT FOR FREEZING
RAIN FROM 00-9Z...AND THE RAIN/SNOW LINE SEEMS TO SET UP FROM
EASTERN MARQUETTE COUNTY TO EASTERN DICKINSON COUNTY. ONCE WE GET
PAST 9Z...THE ENTIRE PROFILE IN THIS AREA DROPS BELOW ZERO.
GENERALLY...MIXED PRECIP TIME LOOKS TO BE QUICK ESPECIALLY GIVEN THE
STRONG DYNAMICS IN THE SYSTEM. MAX TS ALOFT REACH A MAX OF 2C WITH
THE WARM GFS...AND STAY BELOW ZERO WITH THE 00Z ECMWF. EAST OF THIS
LINE...WARM LAYER REACHES 3C AROUND 850 AND THE COLD SURFACE LAYER
IS FAIRLY SHALLOW AND EVEN SNEAKS ABOVE ZERO FROM 6-9Z ACCORDING TO
THE GEM...BRINGING A POT POURRI OF PRECIPITATION. THIS AREA IS STILL
ON TRACK FOR SEEING MORE ICE ACCUMULATION. ALL OTHER AREAS WILL BE
PRIMARILY SNOW.
WINDS ARE A CONSIDERABLE ISSUE WITH THIS SYSTEM AS WELL. STRONG
PRESSURE RISE FALL COUPLET SNEAKS IN WITH THE SYSTEM...BRINGING A
SIGNIFICANT ISALLOBARIC COMPONENT TO THE WIND. THIS IS ESPECIALLY
THE CASE ACROSS EASTERN UPPER MICHIGAN EARLY THURSDAY EVENING UNTIL
AROUND 06Z...AND THEN IN THE WEST AND NORTH CENTRAL BY FRIDAY
MORNING/AFTERNOON. THIS WILL ONLY ADD TO THE REDUCED VISIBILITY WITH
EXTENSIVE BLOWING/DRIFTING SNOW. GUSTS IN SOME OF THESE
AREAS...PARTICULARLY THE EXPOSED REGIONS IN THE WEST-NORTHWEST
FAVORED REGIONS...WILL LIKELY SEE GUSTS INTO THE 40S FRIDAY.
GIVEN THE RECENT MODEL RUNS...FELT CONFIDENT ENOUGH TO GO WITH A
WINTER STORM WARNING FOR LOCATIONS WEST OF MARQUETTE/DICKINSON
COUNTIES. SNOW ACCUMULATIONS RANGE FROM ABOUT 8 TO 12 INCHES IN
THESE COUNTIES. ALSO UPGRADED THE BLIZZARD WATCH TO A WARNING FOR
KEWEENAW/N.HOUGHTON COUNTIES GIVEN THE EXTENSIVE WINDS AND SNOW.
OTHERWISE...KEPT THE REST OF THE CWA UNDER A WINTER STORM WATCH TO
PIN DOWN THE DETAILS. IF THE SYSTEM DOES SNEAK EASTWARD...WE MAY
NEED TO ADD ADDITIONAL COUNTIES INTO THE WARNING. MOST OF THE
UNCERTAINTIES WILL IMPACT THE CENTRAL/EASTERN COUNTIES THE MOST...SO
A WATCH SEEMED BEST RIGHT NOW.
FOR THE EXTENDED...WITH THE LINGERING UPPER LEVEL TROUGH IN THE
AREA...EXPECT COLDER TEMPERATURES TO RETURN. 850MB TEMPS WILL DROP
TOWARDS -25C TO -30C AS WE HEAD FURTHER INTO THE LATER TIME PERIODS.
SNOW WILL GRADUALLY CONFINE TO THE WEST WIND FAVORED REGIONS NEAR
LAKE SUPERIOR...AS ICE WILL LIKELY BE BROKEN ENOUGH TO INDUCE
INSTABILITY FOR LES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1230 PM EST WED FEB 19 2014
EXPECT VFR CONDITIONS TO PREVAIL FOR THE MOST PART AT KIWD/KCMX/KSAW
THRU THE FCST PERIOD WITH JUST A MINOR CONCERN FOR MVFR VIS IN FOG
TONIGHT AT KCMX/KSAW. WITH THICKENING MID CLOUDS AHEAD OF
APPROACHING WINTER STORM...VIS SHOULDN`T DROP VERY LOW IF FOG DOES
IN FACT DEVELOP TONIGHT AS RADIATIONAL COOLING WILL BE MINIMIZED.
THE OUTLOOK FOR LATE THU INTO FRI IS FOR VERY POOR FLYING
CONDITIONS. DISRUPTIONS TO AIR TRAVEL ARE QUITE LIKELY DURING THIS
PERIOD AS A SIGNIFICANT WINTER SNOWSTORM AFFECTS THE REGION. AN
EXTENDED PERIOD OF CONDITIONS BLO AIRFIELD LANDING MINS IS POSSIBLE
AT KCMX BEGINNING AT SOME POINT THU NIGHT OR FRI MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 PM EST WED FEB 19 2014
WINDS WILL DIMINISH THIS EVENING...BECOMING LIGHT UNDER 15KT. WINDS
WILL THEN BEGIN TO INCREASE OVERNIGHT AHEAD OF A WINTER STORM
ORGANIZING OVER THE SOUTHERN PLAINS. E TO NE WINDS MAY REACH UPWARDS
OF 30KT OVER FAR WRN LAKE SUPERIOR BY MORNING. WINDS WILL STEADILY
INCREASE ACROSS THE LAKE THU AS THE ORGANIZING LOW PRES SYSTEM LIFTS
INTO THE MID MISSISSIPPI VALLEY. THE LOW WILL THEN RAPIDLY DEEPEN...
BECOMING AN INTENSE LOW WITH PRES BOTTOMING OUT AROUND 28.7 INCHES
AS IT MOVES NNE ACROSS CNTRL UPPER MI AND CNTRL LAKE SUPERIOR LATE
THU NIGHT AND FRI MORNING. AHEAD OF THE LOW...EASTERLY GALES WILL
DEVELOP OVER CNTRL AND ERN LAKE SUPERIOR THU EVENING. WHILE E TO NE
GALES MAY ALSO DEVELOP OVER WRN LAKE SUPERIOR...W GALES ARE MORE
LIKELY IN THE WAKE OF THE LOW FRI/FRI NIGHT. GALES WILL CONTINUE
OVER CNTRL AND ERN LAKE SUPERIOR FRI THRU SAT WITH THE POTENTIAL FOR
STORM FORCE WINDS OVER ERN LAKE SUPERIOR FRI. ALTHOUGH GALES WILL
END BY SUN...WINDS WILL LIKELY REMAIN IN THE 20-30KT RANGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM EST /3 PM CST/ THURSDAY TO NOON
EST /11 AM CST/ FRIDAY FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ006-007-012>014-085.
BLIZZARD WARNING FROM 7 PM THURSDAY TO 10 PM EST FRIDAY FOR
MIZ001-003.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ005-011.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THURSDAY TO 6 PM EST SATURDAY FOR LSZ244-
245-264>267.
GALE WARNING FROM 7 AM EST /6 AM CST/ FRIDAY TO 7 AM EST /6 AM
CST/ SATURDAY FOR LSZ162-241>243-263.
LAKE MICHIGAN...
GALE WARNING FROM 7 PM THURSDAY TO 5 PM EST FRIDAY FOR LMZ221-
248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MCD
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1234 PM EST WED FEB 19 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 326 AM EST WED FEB 19 2014
WE/LL SEE QUITE A BIT OF SUNSHINE TODAY BUT KEEP AN EYE TO THE
SOUTHWEST AS A STORM DEVELOPS IN THE PLAINS. THAT STORM WILL MOVE
TOWARD THE GREAT LAKES THURSDAY AND STRENGTHEN. INITIALLY...A MIX OF
RAIN, FREEZING RAIN, AND SNOW WILL DEVELOP THURSDAY MORNING BUT
CHANGE TO RAIN FROM SOUTH TO NORTH AS WARMER IS IS DRAWN NORTH.
THUNDERSTORMS ARE POSSIBLE TOO THURSDAY AFTERNOON. STRONG WINDS WILL
DEVELOP THURSDAY NIGHT AND CONTINUE INTO FRIDAY MORNING.
&&
.UPDATE...
ISSUED AT 610 AM EST WED FEB 19 2014
ISSUED A QUICK FORECAST UPDATE TO COVER THE NARROW BAND OF PRECIP
APPROACHING FROM THE WEST. THOUGHT THE DRY AIR WOULD ERODE THIS
PRECIP BEFORE IT GOT HERE BUT A FEW 30 DBZ ECHOES ARE MOVING
ACROSS THE LAKE AND SOME OF IT WILL OBVIOUSLY GET HERE.
PRECIP TYPE IS TRICKY. LATEST RAP FCST SOUNDINGS SUGGEST A MIX OF
LIGHT FREEZING RAIN AND SNOW INITIALLY ALTHOUGH WET BULB EFFECTS
THEN COOL THE SOUNDINGS BELOW FREEZING AS THE COLUMN MOISTENS
SUGGESTING ALL SNOW. THE PRECIP DOES NOT APPEAR HEAVY ENOUGH OR OF
LONG ENOUGH DURATION THAT THE COOLING WOULD BE THAT DRAMATIC SO A
BRIEF LIGHT MIX SEEMS THE MOST LIKELY SCENARIO AS THIS BAND MOVES
THROUGH.
SFC TEMPS SHOULD WARM ABOVE FREEZING AFTER 10 AM SO ANY LINGERING
PRECIP MOVING SOUTH AND EAST OF GRR AT THAT TIME SHOULD BE MIXED
RAIN AND SNOW.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 326 AM EST WED FEB 19 2014
FORECAST CONCERNS DEAL WITH THE APPROACHING STORM THURSDAY.
AFTER A MOSTLY SUNNY DAY SKIES WILL BEGIN TO CLOUD UP TONIGHT. LOW
PRESSURE DEVELOPING OVER THE SOUTHERN PLAINS WILL MOVE NORTHEAST
TUESDAY AND RAPIDLY DEEPEN AS IT MOVES WEST OF THE CWA ACROSS
EASTERN WISCONSIN. PCPN WILL MOVE INTO THE SW CWA AFTER 12Z
THURSDAY. INITIALLY, FORECAST SOUNDINGS SUGGEST THE PCPN WILL BE A
MIX OF RAIN, FREEZING RAIN AND SLEET. NORTH OF I-96, MUCH OF THE
PCPN WILL BE SNOW WITH FREEZING RAIN MIXING IN. I SUSPECT WE`LL NEED
A WINTER WEATHER ADVISORY THURSDAY FOR MUCH OF THE CWA.
H8 WINDS NEAR 70KTS WILL DRAW ABUNDANT WARM AIR NORTHWARD AND THE
PCPN WILL CHANGE TO RAIN FROM SOUTH TO NORTH. QPF IN THE HALF INCH
TO INCH RANGE WILL MOSTLY GET TRAPPED IN THE SNOW PACK AND THAT`S
NOT GOOD NEWS BECAUSE THE ADDED WEIGHT TO THE SNOWPACK WILL LIKELY
RESULT IN MORE ROOF COLLAPSES. PONDING ON ROADS DUE TO CLOGGED STORM
DRAINS WILL ALSO BE AN ISSUES. MODELS SNOW SFC DEWPOINTS RISING
ABOVE FREEZING LATE IN THE DAY AND THAT`S WHEN VISIBILITIES WILL
DECREASE THE MOST.
ALONG WITH THE WARMER AIR WILL COME INCREASED INSTABILITY. ELEVATED
LI`S ARE BELOW 0C AND MUCAPE RISES TO 500 J/KG. GIVEN SHEAR VALUES
OVER 60KTS...WE`LL LIKELY SEE THUNDERSTORMS DEVELOP. THE BEST CHANCE
FOR STRONG TO SEVERE STORMS WILL BE JUST SOUTH OF THE CWA.
AN OCCLUDED FRONT WILL SWEEP IN FROM THE WEST THURSDAY EVENING.
STRONG WEST WINDS WILL DEVELOP AND GUST TO 40-45 MPH AND COLDER AIR
WILL MOVE BACK INTO THE CWA. SNOW SHOWERS AND COLDER TEMPERATURES
ARE EXPECTED FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 326 AM EST WED FEB 19 2014
THE LONG TERM PERIOD WILL FEATURE GENERALLY QUIET WEATHER WITH BELOW
NORMAL TEMPERATURES AS A BROAD UPPER TROUGH REMAINS FIRMLY ANCHORED
OVER MOST OF CANADA AND THE NORTHERN AND EASTERN UNITED STATES. THE
PERSISTENT COLD CYCLONIC FLOW WILL PROMOTE OCCASIONAL LIGHT LAKE
EFFECT SNOW SHOWER ACTIVITY BUT NO SIGNIFICANT ACCUMULATIONS ARE
EXPECTED. CLIPPER TYPE SHORTWAVES DIVING THROUGH THE NORTHWEST FLOW
ALOFT COULD BRING BRIEF PERIODS SNOW SHOWER ENHANCEMENT BUT AGAIN NO
MAJOR SYSTEMS ARE FORESEEN AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1226 PM EST WED FEB 19 2014
THE MAIN CHALLENGE IN THE AVIATION FORECAST DEALS WITH POTENTIAL STRATUS/FOG
OVERNIGHT FOLLOWED BY WINTRY MIX AND IMPACT CEILINGS/VSBYS THU.
WITH THE RELATIVELY WARM TEMPERATURES TODAY RESULTING IN SOME
MELTING...THIS ADDED MOISTURE COULD LEAD TO FOG/STRATUS FORMING
THIS EVENING. NOT CERTAIN TO HAPPEN AND TIMING IS A
CHALLENGE...BUT I AM THINKING THAT AFTER A FEW HOURS OF
RADIATIONAL COOLING WE WILL SEE THESE IMPACT CONDITIONS DEVELOPING
FROM SOUTH TO NORTH THROUGH THE AREA. AS THE APPROACHING STORM
NEARS LATER TONIGHT AND THU AM...THIS WILL ACT TO BREAK UP THE
FOG/STRATUS DECK...POSSIBLY BEFORE 12Z.
THEN PRECIPITATION MOVES IN FROM THE SOUTHWEST...LIKELY AFTER 12Z.
LOW LEVELS LOOK DRY...SO UNLESS SNOW DEVELOPS...WE SHOULD SEE VFR
CONDITIONS WITH ZR/PL FOR A FEW HRS AT THE ONSET. AS THE WARMER
AIR GRADUALLY MOVES IN...CEILINGS AND VISIBILITIES WILL LOWER
THROUGH THE DAY. IFR AND LOWER CONDITIONS LOOK LIKELY BY 18Z THU.
BEYOND 18Z A PROLONGED PERIOD OF SUB IFR LOOKS LIKELY TO OCCUR FOR
ALL SITES.
&&
.HYDROLOGY...
ISSUED AT 141 PM EST TUE FEB 18 2014
RAIN COULD BE HEAVY AT TIMES THURSDAY INTO THURSDAY NIGHT AS
TEMPERATURES WARM UP. UPWARDS OF AN INCH OF RAIN IS FORECASTED. WE
WILL SEE SOME RUNOFF WHICH MAY LEAD TO URBAN AND POOR DRAINAGE
FLOODING. THE WARM TEMPERATURES WILL LAST LESS THAN 24 HRS THEN WE
DROP BACK DOWN BELOW FREEZING. THUS IT APPEARS THAT NOT ENOUGH
RUNOFF WILL OCCUR TO TRIGGER WIDESPREAD FLOODING...INCLUDING ICE
BREAKUP AND JAMS. WILL NEED TO MONITOR THE SITUATION CLOSELY IN
THE COMING DAYS.
ICE JAMS IN RIVERS TEND TO FORM NEAR SHARP BENDS...IN SHALLOW
AREAS...AND NEAR OBSTRUCTIONS...LIKE BRIDGES AND ISLANDS. ICE
BREAKUP ON RIVERS CAN OCCUR WHENEVER THE RIVER STAGE RISES 1.5 TO 3
TIMES THE RIVER ICE THICKNESS. ICE JAMS ON RIVERS CAN RESULT IN
UNPREDICTABLE RAPID RISES ON RIVERS.
UNTIL THEN...LITTLE CHANGE IS EXPECTED ON AREA RIVERS AS ICE REMAINS
LARGELY LOCKED IN PLACE ACROSS MOST RIVERS AND STREAMS AS FLOW IS
NEAR NORMAL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...MJS
HYDROLOGY...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
649 AM EST WED FEB 19 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 326 AM EST WED FEB 19 2014
WE/LL SEE QUITE A BIT OF SUNSHINE TODAY BUT KEEP AN EYE TO THE
SOUTHWEST AS A STORM DEVELOPS IN THE PLAINS. THAT STORM WILL MOVE
TOWARD THE GREAT LAKES THURSDAY AND STRENGTHEN. INITIALLY...A MIX OF
RAIN, FREEZING RAIN, AND SNOW WILL DEVELOP THURSDAY MORNING BUT
CHANGE TO RAIN FROM SOUTH TO NORTH AS WARMER IS IS DRAWN NORTH.
THUNDERSTORMS ARE POSSIBLE TOO THURSDAY AFTERNOON. STRONG WINDS WILL
DEVELOP THURSDAY NIGHT AND CONTINUE INTO FRIDAY MORNING.
&&
.UPDATE...
ISSUED AT 610 AM EST WED FEB 19 2014
ISSUED A QUICK FORECAST UPDATE TO COVER THE NARROW BAND OF PRECIP
APPROACHING FROM THE WEST. THOUGHT THE DRY AIR WOULD ERODE THIS
PRECIP BEFORE IT GOT HERE BUT A FEW 30 DBZ ECHOES ARE MOVING
ACROSS THE LAKE AND SOME OF IT WILL OBVIOUSLY GET HERE.
PRECIP TYPE IS TRICKY. LATEST RAP FCST SOUNDINGS SUGGEST A MIX OF
LIGHT FREEZING RAIN AND SNOW INITIALLY ALTHOUGH WET BULB EFFECTS
THEN COOL THE SOUNDINGS BELOW FREEZING AS THE COLUMN MOISTENS
SUGGESTING ALL SNOW. THE PRECIP DOES NOT APPEAR HEAVY ENOUGH OR OF
LONG ENOUGH DURATION THAT THE COOLING WOULD BE THAT DRAMATIC SO A
BRIEF LIGHT MIX SEEMS THE MOST LIKELY SCENARIO AS THIS BAND MOVES
THROUGH.
SFC TEMPS SHOULD WARM ABOVE FREEZING AFTER 10 AM SO ANY LINGERING
PRECIP MOVING SOUTH AND EAST OF GRR AT THAT TIME SHOULD BE MIXED
RAIN AND SNOW.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 326 AM EST WED FEB 19 2014
FORECAST CONCERNS DEAL WITH THE APPROACHING STORM THURSDAY.
AFTER A MOSTLY SUNNY DAY SKIES WILL BEGIN TO CLOUD UP TONIGHT. LOW
PRESSURE DEVELOPING OVER THE SOUTHERN PLAINS WILL MOVE NORTHEAST
TUESDAY AND RAPIDLY DEEPEN AS IT MOVES WEST OF THE CWA ACROSS
EASTERN WISCONSIN. PCPN WILL MOVE INTO THE SW CWA AFTER 12Z
THURSDAY. INITIALLY, FORECAST SOUNDINGS SUGGEST THE PCPN WILL BE A
MIX OF RAIN, FREEZING RAIN AND SLEET. NORTH OF I-96, MUCH OF THE
PCPN WILL BE SNOW WITH FREEZING RAIN MIXING IN. I SUSPECT WE`LL NEED
A WINTER WEATHER ADVISORY THURSDAY FOR MUCH OF THE CWA.
H8 WINDS NEAR 70KTS WILL DRAW ABUNDANT WARM AIR NORTHWARD AND THE
PCPN WILL CHANGE TO RAIN FROM SOUTH TO NORTH. QPF IN THE HALF INCH
TO INCH RANGE WILL MOSTLY GET TRAPPED IN THE SNOW PACK AND THAT`S
NOT GOOD NEWS BECAUSE THE ADDED WEIGHT TO THE SNOWPACK WILL LIKELY
RESULT IN MORE ROOF COLLAPSES. PONDING ON ROADS DUE TO CLOGGED STORM
DRAINS WILL ALSO BE AN ISSUES. MODELS SNOW SFC DEWPOINTS RISING
ABOVE FREEZING LATE IN THE DAY AND THAT`S WHEN VISIBILITIES WILL
DECREASE THE MOST.
ALONG WITH THE WARMER AIR WILL COME INCREASED INSTABILITY. ELEVATED
LI`S ARE BELOW 0C AND MUCAPE RISES TO 500 J/KG. GIVEN SHEAR VALUES
OVER 60KTS...WE`LL LIKELY SEE THUNDERSTORMS DEVELOP. THE BEST CHANCE
FOR STRONG TO SEVERE STORMS WILL BE JUST SOUTH OF THE CWA.
AN OCCLUDED FRONT WILL SWEEP IN FROM THE WEST THURSDAY EVENING.
STRONG WEST WINDS WILL DEVELOP AND GUST TO 40-45 MPH AND COLDER AIR
WILL MOVE BACK INTO THE CWA. SNOW SHOWERS AND COLDER TEMPERATURES
ARE EXPECTED FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 326 AM EST WED FEB 19 2014
THE LONG TERM PERIOD WILL FEATURE GENERALLY QUIET WEATHER WITH BELOW
NORMAL TEMPERATURES AS A BROAD UPPER TROUGH REMAINS FIRMLY ANCHORED
OVER MOST OF CANADA AND THE NORTHERN AND EASTERN UNITED STATES. THE
PERSISTENT COLD CYCLONIC FLOW WILL PROMOTE OCCASIONAL LIGHT LAKE
EFFECT SNOW SHOWER ACTIVITY BUT NO SIGNIFICANT ACCUMULATIONS ARE
EXPECTED. CLIPPER TYPE SHORTWAVES DIVING THROUGH THE NORTHWEST FLOW
ALOFT COULD BRING BRIEF PERIODS SNOW SHOWER ENHANCEMENT BUT AGAIN NO
MAJOR SYSTEMS ARE FORESEEN AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 648 AM EST WED FEB 19 2014
A NARROW BAND OF LIGHT FREEZING RAIN AND LIGHT SNOW WILL IMPACT
THE TERMINALS FOR ABOUT AN HOUR THIS MORNING RESULTING IN A BRIEF
PERIOD OF MVFR CONDITIONS AND PERHAPS SOME LIGHT ICING. OTHERWISE
VFR CONDITIONS WILL PREVAIL BOTH AHEAD AND BEHIND THIS BAND... WITH
SKIES CLEARING 16-18Z BEHIND THE EXITING/DIMINISHING PRECIP.
&&
.HYDROLOGY...
ISSUED AT 141 PM EST TUE FEB 18 2014
RAIN COULD BE HEAVY AT TIMES THURSDAY INTO THURSDAY NIGHT AS
TEMPERATURES WARM UP. UPWARDS OF AN INCH OF RAIN IS FORECASTED. WE
WILL SEE SOME RUNOFF WHICH MAY LEAD TO URBAN AND POOR DRAINAGE
FLOODING. THE WARM TEMPERATURES WILL LAST LESS THAN 24 HRS THEN WE
DROP BACK DOWN BELOW FREEZING. THUS IT APPEARS THAT NOT ENOUGH
RUNOFF WILL OCCUR TO TRIGGER WIDESPREAD FLOODING...INCLUDING ICE
BREAKUP AND JAMS. WILL NEED TO MONITOR THE SITUATION CLOSELY IN
THE COMING DAYS.
ICE JAMS IN RIVERS TEND TO FORM NEAR SHARP BENDS...IN SHALLOW
AREAS...AND NEAR OBSTRUCTIONS...LIKE BRIDGES AND ISLANDS. ICE
BREAKUP ON RIVERS CAN OCCUR WHENEVER THE RIVER STAGE RISES 1.5 TO 3
TIMES THE RIVER ICE THICKNESS. ICE JAMS ON RIVERS CAN RESULT IN
UNPREDICTABLE RAPID RISES ON RIVERS.
UNTIL THEN...LITTLE CHANGE IS EXPECTED ON AREA RIVERS AS ICE REMAINS
LARGELY LOCKED IN PLACE ACROSS MOST RIVERS AND STREAMS AS FLOW IS
NEAR NORMAL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...MEADE
HYDROLOGY...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
610 AM EST WED FEB 19 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 326 AM EST WED FEB 19 2014
WE/LL SEE QUITE A BIT OF SUNSHINE TODAY BUT KEEP AN EYE TO THE
SOUTHWEST AS A STORM DEVELOPS IN THE PLAINS. THAT STORM WILL MOVE
TOWARD THE GREAT LAKES THURSDAY AND STRENGTHEN. INITIALLY...A MIX OF
RAIN, FREEZING RAIN, AND SNOW WILL DEVELOP THURSDAY MORNING BUT
CHANGE TO RAIN FROM SOUTH TO NORTH AS WARMER IS IS DRAWN NORTH.
THUNDERSTORMS ARE POSSIBLE TOO THURSDAY AFTERNOON. STRONG WINDS WILL
DEVELOP THURSDAY NIGHT AND CONTINUE INTO FRIDAY MORNING.
&&
.UPDATE...
ISSUED AT 610 AM EST WED FEB 19 2014
ISSUED A QUICK FORECAST UPDATE TO COVER THE NARROW BAND OF PRECIP
APPROACHING FROM THE WEST. THOUGHT THE DRY AIR WOULD ERODE THIS
PRECIP BEFORE IT GOT HERE BUT A FEW 30 DBZ ECHOES ARE MOVING
ACROSS THE LAKE AND SOME OF IT WILL OBVIOUSLY GET HERE.
PRECIP TYPE IS TRICKY. LATEST RAP FCST SOUNDINGS SUGGEST A MIX OF
LIGHT FREEZING RAIN AND SNOW INITIALLY ALTHOUGH WET BULB EFFECTS
THEN COOL THE SOUNDINGS BELOW FREEZING AS THE COLUMN MOISTENS
SUGGESTING ALL SNOW. THE PRECIP DOES NOT APPEAR HEAVY ENOUGH OR OF
LONG ENOUGH DURATION THAT THE COOLING WOULD BE THAT DRAMATIC SO A
BRIEF LIGHT MIX SEEMS THE MOST LIKELY SCENARIO AS THIS BAND MOVES
THROUGH.
SFC TEMPS SHOULD WARM ABOVE FREEZING AFTER 10 AM SO ANY LINGERING
PRECIP MOVING SOUTH AND EAST OF GRR AT THAT TIME SHOULD BE MIXED
RAIN AND SNOW.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 326 AM EST WED FEB 19 2014
FORECAST CONCERNS DEAL WITH THE APPROACHING STORM THURSDAY.
AFTER A MOSTLY SUNNY DAY SKIES WILL BEGIN TO CLOUD UP TONIGHT. LOW
PRESSURE DEVELOPING OVER THE SOUTHERN PLAINS WILL MOVE NORTHEAST
TUESDAY AND RAPIDLY DEEPEN AS IT MOVES WEST OF THE CWA ACROSS
EASTERN WISCONSIN. PCPN WILL MOVE INTO THE SW CWA AFTER 12Z
THURSDAY. INITIALLY, FORECAST SOUNDINGS SUGGEST THE PCPN WILL BE A
MIX OF RAIN, FREEZING RAIN AND SLEET. NORTH OF I-96, MUCH OF THE
PCPN WILL BE SNOW WITH FREEZING RAIN MIXING IN. I SUSPECT WE`LL NEED
A WINTER WEATHER ADVISORY THURSDAY FOR MUCH OF THE CWA.
H8 WINDS NEAR 70KTS WILL DRAW ABUNDANT WARM AIR NORTHWARD AND THE
PCPN WILL CHANGE TO RAIN FROM SOUTH TO NORTH. QPF IN THE HALF INCH
TO INCH RANGE WILL MOSTLY GET TRAPPED IN THE SNOW PACK AND THAT`S
NOT GOOD NEWS BECAUSE THE ADDED WEIGHT TO THE SNOWPACK WILL LIKELY
RESULT IN MORE ROOF COLLAPSES. PONDING ON ROADS DUE TO CLOGGED STORM
DRAINS WILL ALSO BE AN ISSUES. MODELS SNOW SFC DEWPOINTS RISING
ABOVE FREEZING LATE IN THE DAY AND THAT`S WHEN VISIBILITIES WILL
DECREASE THE MOST.
ALONG WITH THE WARMER AIR WILL COME INCREASED INSTABILITY. ELEVATED
LI`S ARE BELOW 0C AND MUCAPE RISES TO 500 J/KG. GIVEN SHEAR VALUES
OVER 60KTS...WE`LL LIKELY SEE THUNDERSTORMS DEVELOP. THE BEST CHANCE
FOR STRONG TO SEVERE STORMS WILL BE JUST SOUTH OF THE CWA.
AN OCCLUDED FRONT WILL SWEEP IN FROM THE WEST THURSDAY EVENING.
STRONG WEST WINDS WILL DEVELOP AND GUST TO 40-45 MPH AND COLDER AIR
WILL MOVE BACK INTO THE CWA. SNOW SHOWERS AND COLDER TEMPERATURES
ARE EXPECTED FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 326 AM EST WED FEB 19 2014
THE LONG TERM PERIOD WILL FEATURE GENERALLY QUIET WEATHER WITH BELOW
NORMAL TEMPERATURES AS A BROAD UPPER TROUGH REMAINS FIRMLY ANCHORED
OVER MOST OF CANADA AND THE NORTHERN AND EASTERN UNITED STATES. THE
PERSISTENT COLD CYCLONIC FLOW WILL PROMOTE OCCASIONAL LIGHT LAKE
EFFECT SNOW SHOWER ACTIVITY BUT NO SIGNIFICANT ACCUMULATIONS ARE
EXPECTED. CLIPPER TYPE SHORTWAVES DIVING THROUGH THE NORTHWEST FLOW
ALOFT COULD BRING BRIEF PERIODS SNOW SHOWER ENHANCEMENT BUT AGAIN NO
MAJOR SYSTEMS ARE FORESEEN AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1155 PM EST TUE FEB 18 2014
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH WEDNESDAY. A COLD FRONT
COULD BRING SOME BRIEF MVFR CEILINGS LATE TONIGHT BUT THE CHANCES
WERE LOW ENOUGH TO LEAVE OUT OF THE FORECAST. SOUTHWEST WINDS WILL
GO NORTHWEST BEHIND THE FRONT EARLY WEDNESDAY AND REMAIN AROUND 10
KNOTS.
&&
.HYDROLOGY...
ISSUED AT 141 PM EST TUE FEB 18 2014
RAIN COULD BE HEAVY AT TIMES THURSDAY INTO THURSDAY NIGHT AS
TEMPERATURES WARM UP. UPWARDS OF AN INCH OF RAIN IS FORECASTED. WE
WILL SEE SOME RUNOFF WHICH MAY LEAD TO URBAN AND POOR DRAINAGE
FLOODING. THE WARM TEMPERATURES WILL LAST LESS THAN 24 HRS THEN WE
DROP BACK DOWN BELOW FREEZING. THUS IT APPEARS THAT NOT ENOUGH
RUNOFF WILL OCCUR TO TRIGGER WIDESPREAD FLOODING...INCLUDING ICE
BREAKUP AND JAMS. WILL NEED TO MONITOR THE SITUATION CLOSELY IN
THE COMING DAYS.
ICE JAMS IN RIVERS TEND TO FORM NEAR SHARP BENDS...IN SHALLOW
AREAS...AND NEAR OBSTRUCTIONS...LIKE BRIDGES AND ISLANDS. ICE
BREAKUP ON RIVERS CAN OCCUR WHENEVER THE RIVER STAGE RISES 1.5 TO 3
TIMES THE RIVER ICE THICKNESS. ICE JAMS ON RIVERS CAN RESULT IN
UNPREDICTABLE RAPID RISES ON RIVERS.
UNTIL THEN...LITTLE CHANGE IS EXPECTED ON AREA RIVERS AS ICE REMAINS
LARGELY LOCKED IN PLACE ACROSS MOST RIVERS AND STREAMS AS FLOW IS
NEAR NORMAL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...OSTUNO
HYDROLOGY...MJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1241 AM EST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM EST TUE FEB 18 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A LOW AMPLITUDE TROF
MOVING ACROSS THE NCNTRL STATES/UPPER MISSISSIPPI VALLEY. THERE ARE
SEVERAL VORT MAXES WITHIN THE TROF. AHEAD OF ONE SHORTWAVE OVER NRN
ONTARIO INTO MN...RADAR RETURNS HAVE BEEN SHOWING UP IN NE MN AND
NOW ACROSS LAKE SUPERIOR. GIVEN DRY LOW-LEVELS...PCPN HAS NOT BEEN
ABLE TO REACH THE GROUND.
AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER LAKES TONIGHT...
NOT OUT OF THE QUESTION THAT PATCHY -SN/FLURRIES OR -FZDZ COULD
DEVELOP OVER THE ERN FCST AREA WHERE SHALLOW LOW-LEVEL MOISTURE HAS
ADVECTED N OFF LAKE MICHIGAN. IF LAYER BTWN THE MID LEVEL MOISTURE
AND SHALLOW MOISTURE OFF THE LAKE DOES NOT MOISTEN SUFFICIENTLY...
THEN -FZDZ WILL BE THE PTYPE IF ANY PCPN DOES OCCUR. ELSEWHERE...
HAVE SOME CONCERN FOR -FZDZ OVER THE KEWEENAW WITH WINDS SHIFTING TO
AN UPSLOPE WESTERLY DIRECTION WITH SFC TROF PASSAGE. THERE IS AN
AXIS OF SLIGHTLY HIGHER DWPTS THAT WILL BE ADVECTED INTO THE HIGHER
TERRAIN...AND THIS COULD LEAD TO POSSIBLE STRATUS/FOG AND EVEN
-FZDZ. HOWEVER...WITH FCST SOUNDINGS SHOWING ONLY A VERY SHALLOW SFC
BASED MOIST LAYER AND SINCE MUCH OF WRN LAKE SUPERIOR IS ICED OVER
TO GREATLY LIMIT ANY ADDITIONAL MOISTENING FROM THE LAKE...-FZDZ
POTENTIAL SEEMS VERY MINIMAL ATTM. OUTSIDE OF THOSE CONCERNS...
TONIGHT WILL BE ONE OF THE WARMER NIGHTS IN QUITE A WHILE UNDER
PACIFIC AIR MASS. EXPECT MIN TEMPS GENERALLY IN THE MID TEENS TO
LOWER 20S.
WED WILL BE A DRY DAY AS MIDLEVEL TROF SHIFTS E OF THE AREA AND
SHORTWAVE RIDGING BUILDS INTO THE WRN LAKES. WHILE THERE MIGHT BE
SOME LOW CLOUDS LINGERING INTO WED MORNING OVER THE NW AND MORE
LIKELY THE NE FCST AREA...EXPECT MOST AREAS TO SEE A GOOD DISPLAY OF
SUNSHINE WED. HIGHER MID TO LATE FEB SUN ANGLE WORKING ON THE LOWER
ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE WELL INTO THE 30S AND
EVEN INTO THE LWR 40S ACROSS MUCH OF THE FCST AREA. NOT OUT OF THE
QUESTION FOR A FEW LOCATIONS TO REACH THE MID 40S WHERE DOWNSLOPING
OCCURS. WITH W TO WNW WINDS FOR MUCH OF THE DAY...TEMPS WILL BE
COOLEST NEAR LAKE SUPERIOR OVER WRN UPPER MI AND OVER THE NE FCST
AREA. IN THOSE LOCATIONS...TEMPS SHOULD STRUGGLE TO RISE ABOVE
FREEZING NEAR THE LAKE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 505 PM EST TUE FEB 18 2014
WED NIGHT...
HIGH PRES AND CLEAR TO PARTLY CLOUDY SKIES WILL GIVE WAY
TO INCREASING SRLY WINDS AND MID/HIGH CLOUDS AS THE WAA REGIME
STRENGTHENS AHEAD OF THE MID LEVEL TROUGH OVER THE PLAINS AND SFC
TROUGH MOVING INTO THE UPPER MS VALLEY. LOWS ARE ONLY EXPECTED TO
DROP INTO THE LOWER 20S.
THURSDAY INTO FRIDAY...
THE MODELS HAVE COME INTO RELATIVELY GOOD AGREEMENT WITH THE TRACK
OF THE INTENSIFYING LOW PRESSURE SYSTEM MOVING INTO THE WRN GREAT
LAKES AND THE STRENGTH/POSITION OF THE MID LEVEL FEATURES. THE WPC
FAVORED ECMWF/GEM REMAINED A BIT FARTHER WEST WITH THE TRACK
COMPARED TO THE GFS. SINCE THE 12Z NAM WAS ALSO VERY CLOSE TO THE
ECMWF...IT WAS USED FOR MORE OF THE FCST DETAILS. THE LOW IS
EXPECTED TO RAPIDLY DEEPEN AS IT TRACKS NORTH FROM NEAR MKE AT
00Z/FRI TO NEAR MARQUETTE AT 06Z/FRI AND INTO NRN LAKE SUPERIOR AT
12Z/FRI.
THE POTENT MID LEVEL DYNAMICS WITH STRONG 700-300 QVECTOR CONV AND
FGEN COMBINED WITH ABUNDANT MOISTURE INFLOW SHOULD EASILY BE ABLE TO
PRODUCE QPF AMOUNTS AROUND AN INCH...ESPECIALLY OVER THE WEST THIRD
OF THE CWA. WITH AN ELEVATED DGZ AOA 10K FT...SLR ONLY AROUND 12Z/1
ARE EXPECTED LEADING TO SNOWFALL AMOUNTS AOA 10 INCHES OVER THE WEST
AND AROUND 6 INCHES CENTRAL. MIXED PCPN IS ALSO EXPECTED OVER THE
EAST HALF WITH AN 850-700 MB WARM LAYER MOVING LATE THU INTO THU
EVENING. WITH SFC TEMPS NEAR FREEZING...A MIX OF SN/PL/FZRA BEFORE
THE PCPN CHANGES BACK TO SNOW LATE. THERE IS STILL MORE UNCERTAINTY
ABOUT THE SNOW AMOUNTS AND PCPN TYPE TIMING OVER THE EAST HALF GIVEN
LINGERING MODEL DIFFERENCES. AS THE LOW MOVES NORTH OF UPPER MI LATE
THU NIGHT INTO FRI MORNING...STRONG WEST WINDS ARE EXPECTED TO
DEVELOP. NAM BUFKIT MIXED LAYER WINDS IN THE 40-50 KT RANGE OVER THE
KEWEENAW SUGGEST POTENTIAL FOR VERY STRONG SFC WINDS WITH SEVERE
BLOWING AND DRIFTING SNOW. SO...A BLIZZARD WATCH WAS POSTED FOR THE
KEWEENAW. OTHER LOCATIONS ACROSS THE CWA WILL ALSO SEE BLSN BUT WILL
HAVE FEWER IMPACTS WITH A WEST WIND. THE WINDS WILL ONLY GRADUALLY
DIMINISH FRIDAY AFTERNOON INTO EVENING. ALTHOUGH THE STRONG WINDS MAY
BREAK UP SOME OF THE LAKE ICE...THE REMAINING EXTENSIVE ICE COVER
WILL SIGNIFICANTLY REDUCE CHANCE FOR ADDITIONAL LAKE ENHANCED SNOW OR
LES. HOWEVER...THE UPSLOPE TERRAIN ENHANCEMENT COULD STILL BOOST
SNOWFALL AMOUNTS OVER THE HIGHER TERRAIN OF THE NW CWA.
SAT-TUE...
ONLY SMALL CHANCE POPS WERE INCLUDED NEAR LAKE SUPERIOR FOR WNW/W
FLOW AREAS AS TEMPS ARE SUFFICIENTLY COLD FOR LAKE EFFECT RIGHT
THROUGH THE WEEKEND. WITH THE EXTENSIVE ICE ON LAKE SUPERIOR IT WILL
BE BE INTERESTING TO SEE HOW MUCH OPEN WATER DEVELOPS AFTER THE
STRONG WINDS EXPECTED ON FRIDAY. AWAY FROM ANY LAKE EFFECT...THE
RETURNING COLD WILL BE THE MAIN STORY WITH READINGS BOTH SATURDAY AND
SUNDAY IN THE TEENS. THE COLD REGIME LOOKS TO AS THE WRN CONUS RIDGE
REEMERGES AND ARCTIC HIGH PRES BUILDS INTO THE REGION FROM WRN
CANADA. HOWEVER...THE MODELS WERE LESS AGGRESSIVE IN BRINGING THE
VERY COLD AIR COMPARED TO PREVIOUS RUNS. TEMPS WILL REMAIN WELL BELOW
NORMAL WITH HIGHS FROM 10 TO 15 AND LOWS FROM ZERO TO AT LEAST 5
BELOW. WIND CHILLS MON AND TUE MORNING ARE ALSO EXPECTED TO DROP TO
NEAR 20 BELOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1239 AM EST WED FEB 19 2014
KIWD AND KCMX TO CONTINUE WITH VFR CONDITIONS THROUGH THE FORECAST
PACKAGE. LIFR CIGS AND VISIBILITIES IN FREEZING FOG DEVELOPED
EARLIER THIS EVENING AT KSAW AS WINDS BACKED A BIT MORE SOUTHERLY.
KSAW ON THE EDGE OF THE FOG/STRATUS PER SATELLITE IMAGERY...THUS FOG
SHOULD LIFT ONCE WINDS SHIFT WEST AND DOWNSLOPE STRENGTHENS. LATEST
SHORT-TERM MODEL RUNS KEEPING WINDS LIGHTER AND DELAYING WESTERLY
WIND SHIFT THERE...THUS HAVE KEPT FOG/STRATUS IN KSAW TAF THROUGH
10Z. ONCE FOG DOES LIFT...VFR CONDITIONS TO PREVAIL THROUGH THE
FORECAST. LATEST NAM BUFKIT SOUNDINGS FOR KCMX SUGGEST LOW CIGS MAY
IMPACT THAT SITE LATE IN THE FORECAST AS WINDS BECOME EASTERLY AND
THIS IS SOMETHING THAT WILL NEED TO BE MONITORED.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ006-007-012>014-085.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ005-011.
BLIZZARD WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING FOR
MIZ001-003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...RJT
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
257 PM CST Wed Feb 19 2014
.SHORT TERM: (Through Late Tonight)
Issued at 253 PM CST Wed Feb 19 2014
Main concerns tonight are the potential for localized flooding and
that a few thunderstorms could produce some hail near severe
limits. Showers and scattered thunderstorms have already begun to
develop over southeast Kansas this afternoon in a band of strong
moisture convergence that extends from the Central Plains into the
Mid South. The RAP shows this moisture convergence moving into
central Missouri by 00Z, which will then spreads northeast across the
CWA during the evening. Large scale ascent will increase across the
CWA tonight with the approach of the upper trough. At the same
time, the instability will also increase through the night as lapse
rates steepens with the approach of the upper trough in a highly
sheared environment. Overall coverage with any severe storms
capable of producing quarter size hail between 06-12Z is expected to
be limited in coverage over parts of central, northeast and east
central Missouri as well as adjacent sections of Illinois. A flood
watch will go into effect at midnight tonight where we expect
thunderstorms to move over the remaining snowpack. The ground is
frozen in these areas and streams and area rivers have had problems
with ice jams that could cause some localized flooding. The NMM and
NSSL WRF/GFS simulated reflectivity are similar to going forecast
which already have high chances for showers and thunderstorms this
evening across central and northeast Missouri and west central
Illinois, that then spreads southeast across the rest of the CWA
overnight.
Britt
.LONG TERM: (Thursday through Next Wednesday)
Issued at 253 PM CST Wed Feb 19 2014
Deepening surface low to lift northeast into southeastern Iowa by
18z Thursday, then into Great Lakes region by 06z Friday. In the
meantime, associated cold front to rapidly slide east through
forecast area with another round of showers and thunderstorms on
Thursday. Some of the storms could be strong with isolated severe
storms not out of the question but best chances will be east and
southeast of forecast area. Heaviest rains continue to be in an
axis from central through northeast MO and into west central IL.
Flood watch for portions of central/northeast MO and west central IL,
where there is still snow cover, to remain in effect until 00z
Friday. As for temperatures, will warm up into the mid 40s to
upper 60s by midday, then temperatures to fall through the
afternoon hours as cold front exits region. Another issue to deal
with will be the winds. Winds to pickup from the south ahead of
cold front then veer to the west and increase even more, between
15 and 25 mph with gusts near 35-40 mph at times. At this time no
wind advisory needed, but will need to keep an eye out on future
model runs to see if one will be needed.
Precipitation to move out of forecast area by 00z Friday with winds
gradually diminishing and skies clearing out. Lows will be near
normal in the mid 20s to low 30s.
On Friday, weak surface ridge to build in with winds becoming
southwesterly once again ahead of a weak cold front. Highs will
range from the upper 40s northeast to the upper 50s southwest.
As front slides through late Friday afternoon and Friday night,
energy to remain just north and northeast of forecast area, so
should see dry conditions. Did keep silent slight chance pops over
northeast MO and west central IL on Friday where some light
snow/light rain may be possible, but confidence is low right now.
By Saturday, surface ridge to build back in with cooler conditions
expected. Highs will only be in the upper 30s to mid 50s, but still
near normal for this time of year.
Beyond that, another weak shortwave to approach region Saturday
night, but confidence is low on any precipitation. So kept silent
slight chance pops for portions of forecast area for now. Lows
Saturday night will range from near 20 far north to the low 30s
far south. Dry and colder weather expected Sunday and Sunday night
with highs in the low 30s to mid 40s and lows in the upper teens
to mid 20s.
Next chance for precipitation will be Monday and Monday night,
though best chances will be over northern MO and northern half of
IL, so adjusted pops accordingly. With colder air moving in, the
precipitation will be in the form of light snow with this system.
Colder weather to persist through mid week with highs in the mid 20s
to low 40s each day and lows in the teens to low 20s.
Byrd
&&
.AVIATION: (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1202 PM CST Wed Feb 19 2014
Still looks like VFR conditions through 00Z before thunderstorms
develop across central and northeast Missouri between 00-06Z.
These storms will slowly move eastward overnight tonight and
eventually move into the St. Louis metro TAF sites between 09-11Z.
Low MVFR or IFR conditions will develop in the thunderstorms. LLWS
will also develop overnight as a low level jet will set up over
the area. A cold front will move across the area on Tuesday which
may produce another round of thunderstorms during the afternoon at
the St. Louis metro TAF sites.
Specifics for KSTL: Expect dry and VFR conditions into the early
evening hours before thunderstorm chances increase during the late
evening and overnight hours. Current thinking is that thunderstorms
over central Missouri will move into the TAF site around 09Z. An
additional line of storms is expected to develop ahead of a cold
front on Thursday afternoon. Timing is uncertain, and current
18-20Z group may need to be changed in future TAF issuances based
on cold front timing.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLOOD WATCH from Midnight CST tonight through Thursday afternoon
FOR Audrain MO-Boone MO-Knox MO-Lewis MO-Marion MO-Monroe
MO-Pike MO-Ralls MO-Shelby MO.
IL...FLOOD WATCH from Midnight CST tonight through Thursday afternoon
FOR Adams IL-Brown IL-Greene IL-Macoupin IL-Montgomery IL-
Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
349 PM EST WED FEB 19 2014
.SYNOPSIS...
DEEPENING LOW PRESSURE IN THE GULF OF MAINE THIS EVENING WILL ALLOW
FOR LINGERING SNOW SHOWERS AND FLURRIES ACROSS THE NORTHERN
ADIRONDACKS AND CENTRAL AND NORTHERN GREEN MOUNTAINS THROUGH
MIDNIGHT TONIGHT. OTHERWISE...IT WILL GENERALLY BE DRY WITH PARTIAL
CLEARING BY DAYBREAK. HIGH PRESSURE BRIEFLY BUILDS EASTWARD ACROSS
THE REGION THURSDAY...WITH PARTLY SUNNY SKIES AND MILD AFTERNOON
TEMPERATURES REACHING THE UPPER 30S TO LOWER 40S. A STRONGER STORM
SYSTEM WILL AFFECT THE AREA THURSDAY NIGHT INTO FRIDAY. A PERIOD
OF SLEET AND FREEZING RAIN IS EXPECTED...ESPECIALLY EAST OF THE
GREEN MOUNTAINS EARLY FRIDAY MORNING...AND WILL LIKELY MAKE FOR A
DIFFICULT FRIDAY MORNING COMMUTE ACROSS CENTRAL AND EASTERN VERMONT.
THE WINTRY MIX CHANGES TO ALL RAIN LATER FRIDAY MORNING WITH
LOCALLY GUSTY WINDS. HIGHS FRIDAY WILL REACH THE 40S TO AROUND
50...WARMEST IN THE CHAMPLAIN AND ST. LAWRENCE VALLEYS. A TREND
BACK TOWARD BELOW NORMAL TEMPERATURES IS EXPECTED FOR NEXT WEEK.
&&
.NEAR TERM /UNTIL 7 AM THURSDAY MORNING/...
AS OF 315 PM EST WEDNESDAY...STEADY SNOW IS ENDING ACROSS
CENTRAL/ERN VT LATE THIS AFTN AS DEVELOPING SFC LOW ACROSS SERN MA
TRACKS NEWD INTO THE GULF OF MAINE. RECEIVED REPORTS OF 3-4"
ACROSS RUTLAND AND WINDSOR COUNTIES THIS AFTERNOON...SO LIKELY
SOME LINGERING SLOW TRAVEL THRU THE EVENING COMMUTE DUE TO SNOW
COVERED ROADWAYS.
HIGH RESOLUTION MODELS CONTINUE TO INDICATE LINGERING FLURRY OR
LIGHT SNOW SHOWER ACTIVITY IN THE NRN ADIRONDACKS AND NRN GREEN
MTNS. THIS IS CONSISTENT WITH INCREASING TREND IN RADAR
REFLECTIVITY ACROSS ERN FRANKLIN VT/CHITTENDEN COUNTY DURING THE
PAST HOUR. MAY SEE LOCALIZED 1-2" AMTS ACROSS THE MTNS
THIS EVENING...WITH ACTIVITY DIMINISHING AFTER MIDNIGHT. PARTIAL
CLEARING IS EXPECTED BY DAYBREAK AREAWIDE AS SHORTWAVE RIDGE
BUILDS INTO NRN NY TOWARD 12Z WEDNESDAY. LOWS WILL BE ABOVE
AVERAGE TONIGHT AS AIR MASS CONTINUES TO MODERATE...AND CLOUDS
LIMIT RADIATIVE COOLING TO SOME EXTENT. LOOKING FOR LOWS GENERALLY
IN THE UPPER TEENS TO MID 20S...HIGHEST IN THE CHAMPLAIN VLY.
&&
.SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 315 PM EST WEDNESDAY...QUIET AND MILD CONDITIONS THURSDAY.
SFC RIDGE AND SHORTWAVE RIDGING ALOFT WILL BISECT THE NORTH
COUNTRY AT 18Z. 850MB TEMPS MODERATE TO -1C TO -3C...AND THIS
SHOULD ALLOW SFC TEMPS TO RISE INTO UPPER 30S TO LOWER 40S. MOSTLY
SUNNY IN THE MORNING...BUT SHOULD SEE AN INCREASE IN MID-UPR LEVEL
CLOUD COVER DURING THE AFTN WITH ONSET OF ISENTROPIC ASCENT IN
ADVANCE OF NEXT FRONTAL SYSTEM.
RAPIDLY DEEPENING SFC CYCLONE (970MB BY 12Z FRIDAY) TRACKING NEWD
THRU THE CENTRAL GREAT LAKES THURSDAY NIGHT IS ASSOCIATED WITH A
LEADING WARM FRONT AND STRONG SLY LOW-LEVEL JET WHICH WILL BE
LIFTING THRU THE NORTH COUNTRY. THE 12Z NWP GUIDANCE IS A BIT
QUICKER WITH ONSET OF MIXED WINTRY PRECIPITATION ACROSS THE
REGION...WITH STRONG WAA BRINGING WIDESPREAD STRATIFORM PCPN INTO
THE AREA. PRECIPITATION WILL REACH THE ADIRONDACKS AND S-CENTRAL
VT BY MIDNIGHT...AND OVERSPREAD THE REMAINDER OF THE REGION DURING
THE PRE-DAWN HOURS. IT APPEARS A QUICK CHANGE FROM SNOW TO
SLEET/FREEZING RAIN IS LIKELY IN THE ADIRONDACKS...NRN ST. LAWRENCE
VALLEY...AND POINTS EAST OF THE GREEN MTNS DURING THE PRE-DAWN HRS
FRIDAY...LASTING INTO THE MORNING COMMUTE. IN THE CHAMPLAIN
VALLEY...WET SNOW TO MAINLY RAIN EXPECTED WITH LOCALLY ABOVE 32F
TEMPS. SFC TEMPS REMAIN 28-32F LONGEST EAST OF THE GREEN
MTNS...AND WITH TEMPS REACHING +4 TO +6C IN SOUNDING WARM "NOSE"
BETWEEN 850-800MB...THERMODYNAMIC PROFILES STRONGLY FAVOR PERIOD
OF FREEZING RAIN ACROSS CENTRAL/ERN VT. ICY ROAD CONDITIONS WITH
COLD GROUND CONDITIONS WILL MAKE FOR A HAZARDOUS MORNING COMMUTE
AWAY FROM THE CHAMPLAIN VALLEY...ESPECIALLY CENTRAL/ERN VT. A
WINTER WEATHER ADVISORY MAY EVENTUALLY BE REQUIRED AS WE GET
CLOSER TO THE EVENT. TOTAL ICE WILL GENERALLY REMAIN BELOW 0.2"
MAX...SO MAIN IMPACT WILL BE TO TRANSPORTATION. ANY SNOW/SLEET AT
THE START OF THE PRECIPITATION EVENT WILL AMOUNT TO 2" OR LESS.
SOME GUSTY DOWNSLOPE WINDS ARE ALSO POSSIBLE EARLY FRIDAY...SE
20-30 WITH GUSTS TO 40 MPH ALONG THE WRN SLOPES OF THE GREEN MTNS.
THIS WOULD MAINLY OCCUR BETWEEN 06-15Z FRIDAY. FOLLOWING COLD
FRONTAL PASSAGE...STEEP LOW-LEVEL LAPSE RATES AND CHANNELED FLOW
IN THE ST. LAWRENCE VALLEY WILL LIKELY YIELD SOME SW GUSTS 40-45
MPH. WINDS SHOULD NOT BE QUITE AS STRONG ELSEWHERE.
QPF AMTS EXPECTED TO RANGE FROM 0.4"-0.8"...HIGHEST IN THE
ADIRONDACKS WITH UPSLOPE FLOW AND INTO THE CENTRAL GREEN MTNS.
LOCAL SHADOWING AFFECTS IN THE CHAMPLAIN VALLEY WILL RESULT IN
TOTAL PRECIPITATION ON THE LOW END OF THE RANGE. DESPITE TEMPS
WELL INTO THE 40S TO NEAR 50F...NOT ANTICIPATING ANY SIGNIFICANT
HYDRO CONCERNS AS OUTLINED IN HYDRO SECTION BELOW.
CLEARING FRIDAY NIGHT WITH WLY FLOW. AIR MASS IS NOT PARTICULARLY
COLD IN THE WAKE OF THE COLD FRONT PER NAM/GFS THERMAL FIELDS.
KEPT LOWS GENERALLY IN THE 20S FOR FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 250 PM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE OF
FCSTS WITH REGARDS TO LARGE SCALE SYNOPTIC PATTERN WHICH SUPPORTS
DEEP FULL LATITUDE MID/UPPER LVL TROF DEVELOPING ACRS THE EASTERN
CONUS. THIS WL SUPPORT A TREND TWD BLW NORMAL TEMPS BY EARLY NEXT
WEEK...ALONG WITH BLW NORMAL CHCS FOR PRECIP. GIVEN THE POSITION
OF TROF AXIS AND SFC HIGH PRES...EXPECTING A FAST WESTERLY
CONFLUENT FLW ACRS OUR CWA...WITH NO INTERACTION OF SUB TROPICAL
MOISTURE INTO OUR REGION. THE COMBINATION OF S/W ENERGY IN THE FLW
ALOFT AND SFC TROFS EVERY COUPLE OF DAYS...WL RESULT IN MAINLY ON
AND OFF MTN SNOW SHOWERS THRU THE PERIOD...BUT ACCUMULATIONS WL BE
LIGHT. TEMPS WL START MUCH ABOVE NORMAL FOR SAT WITH PROGGED 925MB
TEMPS RANGING FROM -2C SLV TO +2C CT RIVER VALLEY...SUPPORTING L/M
30S MTNS L/M 40S VALLEYS...ESPECIALLY LWR CT RIVER VALLEY. BY
SUNDAY...925MB TEMPS FALL ANOTHER 3 TO 6 DEGREES SUPPORTING HIGHS
BACK INTO THE 20S MTNS TO 30S VALLEYS. THIS TREND OF COOLING LLVL
THERMAL PROFILES BY 3 TO 6 DEGREES A DAY CONTINUES FOR MONDAY INTO
TUESDAY...WITH EXPECTED HIGHS IN THE TEENS TO L/M20S ANTICIPATED.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...IFR CONDITIONS WL OCCUR AT RUT/MPV THRU 21Z
TODAY...WITH POTENTIAL IFR CIGS/VIS DEVELOPING AT SLK BY 23Z THIS
EVENING. CRNT RADAR SHOWS BAND OF MODERATE SNOW LIFTING ACRS
CENTRAL/SOUTHERN VT...IMPACTING MPV/RUT WITH VIS BLW 1SM. BASED ON
RAP13 AND HRRR MODEL PROGGED COMPOSITE REFLECTIVITY EXPECT THIS
ACTIVITY TO BE EAST OF OUR TAF SITES BY 21Z WITH MAINLY MVFR
CONDITIONS PREVAILING. AT SLK THINKING WEAK SFC TROF WL SHIFT THE
WINDS TO THE WEST/NORTHWEST THIS EVENING WITH LLVL CLOUDS AND
LIGHT SNOW DEVELOPING. THIS WL RESULT IN A PERIOD OF IFR
CONDITIONS AT SLK WITH VIS BLW 2SM AND CIGS BLW OVC 1000 FT.
ELSEWHERE...EXPECTING MAINLY VFR WITH BRIEF PERIODS OF MVFR AT
MSS/BTV THRU THIS EVENING. WEAK SFC RIDGE WITH VFR CONDITIONS WL
PREVAIL LATE TONIGHT INTO 18Z WEDS AT OUR TAF SITES.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
VFR CONDITIONS WITH THICKENING CLOUDS THRU 00Z FRIDAY. SFC WARM
FRNT WL RESULT IN MIXED PRECIP DEVELOPING BY 06Z FRIDAY WITH SOME
ICE ACCUMULATION POSSIBLE AT MPV...ALONG WITH WIDESPREAD MVFR/IFR
CONDITIONS LIKELY BTWN 06Z-12Z FRIDAY. ANOTHER BAND OF MAINLY RAIN
SHOWERS OCCURS FRIDAY WITH MVFR CONDITIONS...WITH EXCEPTION OF IFR
POSSIBLE AT MSS/SLK/MPV. ALSO...WITH WARM TEMPS MOVING OVER
RELATIVELY COLD SFC TEMPS/SNOWPACK AREAS OF FOG/BR WL BE POSSIBLE
IN THE DEEPER PROTECTED VALLEY LOCATIONS OF VT/NY FRIDAY INTO
SATURDAY. STRONG LLVL JET WL RESULT IN AREAS OF LLVL WS ON
FRIDAY...ESPECIALLY AT MSS WITH NORTHEAST SFC WINDS AND SW WINDS
ALOFT AT 1500 FEET AND AT MPV WITH LIGHT SFC WINDS ANTICIPATED AND
STRONG 1000 AGL WINDS OF 45 TO 50 KNTS. GUSTY SE WINDS OF 30 TO 35
KNTS WL BE POSSIBLE AT RUTLAND ON FRIDAY MORNING...WHICH WL SHIFT
TO THE SOUTHWEST AND BECM GUSTY AT MSS/SLK/PBG/BTV DURING THE
AFTN/EVENING OF FRIDAY. OTHERWISE...DRY SLOT WL RESULT IN VFR
CONDITIONS DEVELOPING FRIDAY NIGHT AND PREVAILING INTO SUNDAY.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGICAL ISSUES FORESEEN WITH BRIEF WARMUP
THURSDAY AND FRIDAY AS SNOWPACK IS NOT RIPE FOR RAPID SNOWMELT. MOST
OF THE EXPECTED PRECIPITATION FRIDAY (BASIN AVG AROUND 0.40"-0.70")
IS EXPECTED TO BE ABSORBED INTO THE SNOWPACK GIVEN CURRENT
CHARACTERISTICS OF SNOWPACK. THAWING DEGREE HOURS REACH NEAR 300
ACROSS A LIMITED AREA OF ADDISON/RUTLAND COUNTY AND IN ST. LAWRENCE
COUNTY NY...WHERE TEMPERATURES WILL APPROACH 48-50F FOR A TIME
FRIDAY. SHOULD ANY MINOR ICE JAMS DEVELOP FRIDAY OR FRIDAY
NIGHT...WILL LIKELY BE CONFINED TO RUTLAND/ADDISON/ST. LAWRENCE
COUNTIES...AND ON THE SMALLER RIVERS AND STREAMS. LOW PROBABILITY
OF ANY ICE JAM FLOODING AT THIS POINT...BUT WE WILL CONTINUE TO
MONITOR.
&&
.EQUIPMENT...
DAMAGED EQUIPMENT HAS RESULTED IN AN AUDIBLE HUM ON THE MOUNT
ASCUTNEY NOAA WEATHER RADIO BROADCAST (WXM-44). OUR TECHNICIANS
ARE AWARE OF THE PROBLEM AND WILL RESOLVE THE ISSUE AS QUICKLY AS
POSSIBLE. REPAIRS MAY INVOLVE COORDINATION AND ACCESS BY
TELCO...INCLUDING PARTS ACQUISITION. THIS MAY TAKE 1-2 DAYS TO
RESOLVE. IN THE MEANTIME...WE APOLOGIZE FOR ANY DIFFICULTIES IN
HEARING THE BROADCAST FROM MOUNT ASCUTNEY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
HYDROLOGY...BANACOS
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
247 PM EST WED FEB 19 2014
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL BRING PERIODS OF LIGHT SNOW TO THE
REGION THIS AFTERNOON INTO EARLY TONIGHT. A STRONGER STORM SYSTEM WILL
AFFECT THE AREA THURSDAY NIGHT INTO FRIDAY WITH MILDER TEMPERATURES
ALONG WITH A MIX OF WINTRY PRECIPITATION AND LOCALLY GUSTY WINDS.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1230 PM EST WEDNESDAY...NO SIGNIFICANT CHANGES TO PREVIOUS
FORECAST. RADAR TRENDS SUGGEST 1-2 HOUR PERIOD OF MODERATE SNOW
ACROSS S-CENTRAL VT NEWD ACROSS CENTRAL/ERN VT THIS AFTN. SHOULD
SEE A QUICK 2-3" OF SNOW THRU 21Z BEFORE BEST UVV SHIFTS EWD. A
SPECIAL WX STATEMENT HAS BEEN ISSUED TO COVER THIS
POTENTIAL...WITH SOME SLOW TRAVEL CONDITIONS EXPECTED CENTRAL/ERN
VT THIS AFTN. REMAINDER OF THE FCST IS UNCHANGED.
PREVIOUS DISCUSSION...OVERCAST SKIES IN PLACE ACROSS THE NORTH
COUNTRY THIS MORNING IN ADVANCE OF A SHORTWAVE TROUGH CROSSING THE
EASTERN GREAT LAKES REGION AND ASSOCIATED SFC TROUGH ACROSS SERN
ONTARIO/WRN NY. SIMILAR TO YESTERDAY...A SECONDARY LOW PRESSURE
SYSTEM IS EXPECTED TO DEVELOP ACROSS SOUTHERN NEW ENGLAND THIS
AFTN AND THEN DEEPEN ACROSS THE GULF OF MAINE THIS EVENING. MOST
OF THE ASSOCIATED PRECIPITATION IS FOCUSED SOUTH AND EAST OF OUR
FORECAST AREA. THAT SAID...NAM...BTV-4KM AND 12KM WRF DO SHOW AN
INCREASE IN PRECIPITATION COVERAGE ACROSS VERMONT AROUND
18Z...LASTING THRU THIS EVENING. NO SIGNIFICANT CHANGES OTHER THAN
TO LOWER POPS/QPF A BIT ACROSS NRN NY. OVERALL LOOKING AT 0.10 TO
0.15" ACROSS VT AND < 0.10" ACROSS NRN NY. GENERALLY LOOKING AT
SNOW...ALTHOUGH PBL TEMPS WARM ABOVE FREEZING AND NEAR-SFC WARM
LAYER SHOULD BE ENOUGH FOR CONDITIONAL RAIN/SNOW MIX WITH ANYTHING
THAT FALLS ACROSS SWRN ST. LAWRENCE COUNTY TODAY.
ELSEWHERE...VALLEY TEMPS REACH THE MID 30S ACROSS WRN VT...SO
LIKELY LOOKING AT LIMITED ACCUMULATIONS ON ROAD SURFACES. SNOWFALL
FCST IS A DUSTING TO 1" ACROSS THE CHAMPLAIN VALLEY AND GENERALLY
1-3" ACROSS CENTRAL AND ERN VT. HIGHEST SNOW TOTALS ARE LIKELY
ACROSS THE CENTRAL GREEN MTNS THIS AFTN THRU THE FIRST PART OF
TONIGHT. HIGH TEMPS RANGE FROM 34-37F IN THE CHAMPLAIN VALLEY TO
30-33F EAST OF THE GREEN MTNS. HIGHS IN THE LOWER-MID 40S EXPECTED
ACROSS SRN ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 459 AM EST WEDNESDAY...CHANCES FOR SNOW WILL TAPER OFF
TONIGHT...BUT AN ADDITIONAL INCH OR TWO IS POSSIBLE OVER NORTH
CENTRAL AND NORTHEAST VERMONT BEFORE IT WINDS DOWN BY AROUND
MIDNIGHT. EXPECT PLENTY OF CLOUDS HOWEVER... ESPECIALLY NORTH.
LOOK FOR MIN TEMPS IN THE UPPER TEENS TO MID 20S.
THURSDAY WILL BE QUIET AS SURFACE HIGH SLIDES EAST ACROSS THE REGION
AND REACHES THE EAST COAST BY EVENING. EXPECT A DECREASE IN CLOUD
COVER IN THE MORNING...FOLLOWED BY AN INCREASE IN CLOUDS AGAIN
LATER IN THE DAY IN ADVANCE OF NEXT AREA OF LOW PRESSURE
AND ASSOCIATED FRONTAL SYSTEM. IT SHOULD REMAIN MOSTLY DRY THROUGH
THE DAYLIGHT HOURS HOWEVER. WINDS TURN INTO THE SOUTH IN BETWEEN
DEPARTING HIGH AND APPROACHING LOW. WITH 850 MB TEMPS CLIMBING TO
NEAR 0C BY 00Z FRIDAY...WE CAN EXPECT A RATHER MILD DAY WITH HIGHS
IN THE MID 30S TO AROUND 40.
STRONG/HIGH AMPLITUDE MID-LEVEL TROUGH ACROSS THE CENTRAL
MISSISSIPPI VALLEY THURSDAY NIGHT RESULTS IN RAPIDLY DEEPENING LOW
PRESSURE ACROSS THE GREAT LAKES REGION (968MB PER 00Z GFS AT 12Z
FRIDAY OVER LAKE SUPERIOR). STRONG SOUTHERLY LOW-LEVEL JET DEVELOPS
DURING THURSDAY NIGHT...WITH 55-60 KTS AT 850MB BY DAYBREAK FRIDAY.
STRONG WARM FRONTAL ASCENT WILL BRING STRATIFORM PRECIPITATION TO
THE REGION...ESPECIALLY AFTER MIDNIGHT THURSDAY NIGHT.
PRECIPITATION TYPE WILL BE AN ISSUE ACROSS MUCH OF THE AREA THURSDAY
NIGHT. ABOVE FREEZING TEMPS LIKELY IN THE CHAMPLAIN VALLEY
SUPPORTING MAINLY RAIN...ALTHOUGH SOME EVAPORATIONAL COOLING AT
ONSET OF PRECIPITATION MAY SUPPORT A BRIEF PERIOD OF SLEET AND SNOW.
MODEL SOUNDINGS INDICATE THAT TEMPS ACROSS THE REST OF THE FORECAST
AREA WILL BE BELOW FREEZING NEAR THE SURFACE WITH FAVORABLE
PROFILES FOR A PERIOD OF SLEET AND POSSIBLE FREEZING RAIN. LOOK FOR
ANY ICING TO BE MINIMAL AND OF SHORT DURATION OVER MUCH OF THE
ADIRONDACKS AND SAINT LAWRENCE VALLEY. EAST OF THE GREEN
MOUNTAINS...SOME AREAS WILL SEE THE THREAT OF FREEZING RAIN LINGER
INTO MID MORNING FRIDAY AS TEMPS STRUGGLE TO CLIMB ABOVE FREEZING IN
THE SHELTERED VALLEYS. THIS MAY RESULT IN SOME TRAVEL IMPACT
DURING THE PRE-DAWN HRS INTO THE EARLY MORNING COMMUTE ON FRIDAY.
ALSO LOOKING AT LOCALLY STRONG AND GUSTY WINDS...ESPECIALLY ALONG
THE WESTERN SLOPES WHERE GUSTS MAY TOP 40 MPH FOR A TIME. THESE
WINDS WILL SHIFT TO THE SOUTHWEST WITH FRONTAL PASSAGE FROM LATE
FRIDAY MORNING THROUGH AFTERNOON ACROSS THE AREA...WITH STRONGEST
WINDS POST FROPA OVER SAINT LAWRENCE VALLEY.
AS FOR THE PRECIPITATION...THE WARM AIR ADVECTION RAIN/FREEZING RAIN
WILL BE LATE THURSDAY NIGHT THROUGH EARLY FRIDAY. MAYBE A BRIEF LULL
IN THE PRECIPITATION BEFORE MORE CONVECTIVE TYPE SHOWERS ASSOCIATED
WITH COLD FRONT QUICKLY OVERSPREAD THE REGION FROM WEST TO EAST.
EXPECT FROPA IN SAINT LAWRENCE VALLEY BY 15Z FRIDAY AND IN
EASTERN VERMONT BY AROUND 21Z. THIS PRECIPITATION EXPECTED TO BE
ALL IN THE FORM OF RAIN WITH MAX TEMPS RANGING FROM THE UPPER 30S
EASTERN VERMONT TO THE UPPER 40S IN ACROSS NORTHERN NEW YORK AND
SOUTHWEST VERMONT. PRECIPITATION TOTALS FROM THURSDAY NIGHT
THROUGH FRIDAY EXPECTED TO RANGE FROM ONE HALF TO ONE INCH...WITH
SOME LOCALLY HIGHER AMOUNTS POSSIBLE.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 250 PM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE OF
FCSTS WITH REGARDS TO LARGE SCALE SYNOPTIC PATTERN WHICH SUPPORTS
DEEP FULL LATITUDE MID/UPPER LVL TROF DEVELOPING ACRS THE EASTERN
CONUS. THIS WL SUPPORT A TREND TWD BLW NORMAL TEMPS BY EARLY NEXT
WEEK...ALONG WITH BLW NORMAL CHCS FOR PRECIP. GIVEN THE POSITION
OF TROF AXIS AND SFC HIGH PRES...EXPECTING A FAST WESTERLY
CONFLUENT FLW ACRS OUR CWA...WITH NO INTERACTION OF SUB TROPICAL
MOISTURE INTO OUR REGION. THE COMBINATION OF S/W ENERGY IN THE FLW
ALOFT AND SFC TROFS EVERY COUPLE OF DAYS...WL RESULT IN MAINLY ON
AND OFF MTN SNOW SHOWERS THRU THE PERIOD...BUT ACCUMULATIONS WL BE
LIGHT. TEMPS WL START MUCH ABOVE NORMAL FOR SAT WITH PROGGED 925MB
TEMPS RANGING FROM -2C SLV TO +2C CT RIVER VALLEY...SUPPORTING L/M
30S MTNS L/M 40S VALLEYS...ESPECIALLY LWR CT RIVER VALLEY. BY
SUNDAY...925MB TEMPS FALL ANOTHER 3 TO 6 DEGREES SUPPORTING HIGHS
BACK INTO THE 20S MTNS TO 30S VALLEYS. THIS TREND OF COOLING LLVL
THERMAL PROFILES BY 3 TO 6 DEGREES A DAY CONTINUES FOR MONDAY INTO
TUESDAY...WITH EXPECTED HIGHS IN THE TEENS TO L/M20S ANTICIPATED.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...IFR CONDITIONS WL OCCUR AT RUT/MPV THRU 21Z
TODAY...WITH POTENTIAL IFR CIGS/VIS DEVELOPING AT SLK BY 23Z THIS
EVENING. CRNT RADAR SHOWS BAND OF MODERATE SNOW LIFTING ACRS
CENTRAL/SOUTHERN VT...IMPACTING MPV/RUT WITH VIS BLW 1SM. BASED ON
RAP13 AND HRRR MODEL PROGGED COMPOSITE REFLECTIVITY EXPECT THIS
ACTIVITY TO BE EAST OF OUR TAF SITES BY 21Z WITH MAINLY MVFR
CONDITIONS PREVAILING. AT SLK THINKING WEAK SFC TROF WL SHIFT THE
WINDS TO THE WEST/NORTHWEST THIS EVENING WITH LLVL CLOUDS AND
LIGHT SNOW DEVELOPING. THIS WL RESULT IN A PERIOD OF IFR
CONDITIONS AT SLK WITH VIS BLW 2SM AND CIGS BLW OVC 1000 FT.
ELSEWHERE...EXPECTING MAINLY VFR WITH BRIEF PERIODS OF MVFR AT
MSS/BTV THRU THIS EVENING. WEAK SFC RIDGE WITH VFR CONDITIONS WL
PREVAIL LATE TONIGHT INTO 18Z WEDS AT OUR TAF SITES.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
VFR CONDITIONS WITH THICKENING CLOUDS THRU 00Z FRIDAY. SFC WARM
FRNT WL RESULT IN MIXED PRECIP DEVELOPING BY 06Z FRIDAY WITH SOME
ICE ACCUMULATION POSSIBLE AT MPV...ALONG WITH WIDESPREAD MVFR/IFR
CONDITIONS LIKELY BTWN 06Z-12Z FRIDAY. ANOTHER BAND OF MAINLY RAIN
SHOWERS OCCURS FRIDAY WITH MVFR CONDITIONS...WITH EXCEPTION OF IFR
POSSIBLE AT MSS/SLK/MPV. ALSO...WITH WARM TEMPS MOVING OVER
RELATIVELY COLD SFC TEMPS/SNOWPACK AREAS OF FOG/BR WL BE POSSIBLE
IN THE DEEPER PROTECTED VALLEY LOCATIONS OF VT/NY FRIDAY INTO
SATURDAY. STRONG LLVL JET WL RESULT IN AREAS OF LLVL WS ON
FRIDAY...ESPECIALLY AT MSS WITH NORTHEAST SFC WINDS AND SW WINDS
ALOFT AT 1500 FEET AND AT MPV WITH LIGHT SFC WINDS ANTICIPATED AND
STRONG 1000 AGL WINDS OF 45 TO 50 KNTS. GUSTY SE WINDS OF 30 TO 35
KNTS WL BE POSSIBLE AT RUTLAND ON FRIDAY MORNING...WHICH WL SHIFT
TO THE SOUTHWEST AND BECM GUSTY AT MSS/SLK/PBG/BTV DURING THE
AFTN/EVENING OF FRIDAY. OTHERWISE...DRY SLOT WL RESULT IN VFR
CONDITIONS DEVELOPING FRIDAY NIGHT AND PREVAILING INTO SUNDAY.
&&
.EQUIPMENT...
DAMAGED EQUIPMENT HAS RESULTED IN AN AUDIBLE HUM ON THE MOUNT
ASCUTNEY NOAA WEATHER RADIO BROADCAST (WXM-44). OUR TECHNICIANS
ARE AWARE OF THE PROBLEM AND WILL RESOLVE THE ISSUE AS QUICKLY AS
POSSIBLE. REPAIRS MAY INVOLVE COORDINATION AND ACCESS BY
TELCO...INCLUDING PARTS ACQUISITION. THIS MAY TAKE 1-2 DAYS TO
RESOLVE. IN THE MEANTIME...WE APOLOGIZE FOR ANY DIFFICULTIES IN
HEARING THE BROADCAST FROM MOUNT ASCUTNEY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS/RJS
NEAR TERM...BANACOS
SHORT TERM...RJS
LONG TERM...TABER
AVIATION...TABER
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
102 PM EST WED FEB 19 2014
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL BRING PERIODS OF LIGHT SNOW TO THE
REGION THIS AFTERNOON INTO EARLY TONIGHT. A STRONGER STORM SYSTEM WILL
AFFECT THE AREA THURSDAY NIGHT INTO FRIDAY WITH MILDER TEMPERATURES
ALONG WITH A MIX OF WINTRY PRECIPITATION AND LOCALLY GUSTY WINDS.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1230 PM EST WEDNESDAY...NO SIGNIFICANT CHANGES TO PREVIOUS
FORECAST. RADAR TRENDS SUGGEST 1-2 HOUR PERIOD OF MODERATE SNOW
ACROSS S-CENTRAL VT NEWD ACROSS CENTRAL/ERN VT THIS AFTN. SHOULD
SEE A QUICK 2-3" OF SNOW THRU 21Z BEFORE BEST UVV SHIFTS EWD. A
SPECIAL WX STATEMENT HAS BEEN ISSUED TO COVER THIS
POTENTIAL...WITH SOME SLOW TRAVEL CONDITIONS EXPECTED CENTRAL/ERN
VT THIS AFTN. REMAINDER OF THE FCST IS UNCHANGED.
PREVIOUS DISCUSSION...OVERCAST SKIES IN PLACE ACROSS THE NORTH
COUNTRY THIS MORNING IN ADVANCE OF A SHORTWAVE TROUGH CROSSING THE
EASTERN GREAT LAKES REGION AND ASSOCIATED SFC TROUGH ACROSS SERN
ONTARIO/WRN NY. SIMILAR TO YESTERDAY...A SECONDARY LOW PRESSURE
SYSTEM IS EXPECTED TO DEVELOP ACROSS SOUTHERN NEW ENGLAND THIS
AFTN AND THEN DEEPEN ACROSS THE GULF OF MAINE THIS EVENING. MOST
OF THE ASSOCIATED PRECIPITATION IS FOCUSED SOUTH AND EAST OF OUR
FORECAST AREA. THAT SAID...NAM...BTV-4KM AND 12KM WRF DO SHOW AN
INCREASE IN PRECIPITATION COVERAGE ACROSS VERMONT AROUND
18Z...LASTING THRU THIS EVENING. NO SIGNIFICANT CHANGES OTHER THAN
TO LOWER POPS/QPF A BIT ACROSS NRN NY. OVERALL LOOKING AT 0.10 TO
0.15" ACROSS VT AND < 0.10" ACROSS NRN NY. GENERALLY LOOKING AT
SNOW...ALTHOUGH PBL TEMPS WARM ABOVE FREEZING AND NEAR-SFC WARM
LAYER SHOULD BE ENOUGH FOR CONDITIONAL RAIN/SNOW MIX WITH ANYTHING
THAT FALLS ACROSS SWRN ST. LAWRENCE COUNTY TODAY.
ELSEWHERE...VALLEY TEMPS REACH THE MID 30S ACROSS WRN VT...SO
LIKELY LOOKING AT LIMITED ACCUMULATIONS ON ROAD SURFACES. SNOWFALL
FCST IS A DUSTING TO 1" ACROSS THE CHAMPLAIN VALLEY AND GENERALLY
1-3" ACROSS CENTRAL AND ERN VT. HIGHEST SNOW TOTALS ARE LIKELY
ACROSS THE CENTRAL GREEN MTNS THIS AFTN THRU THE FIRST PART OF
TONIGHT. HIGH TEMPS RANGE FROM 34-37F IN THE CHAMPLAIN VALLEY TO
30-33F EAST OF THE GREEN MTNS. HIGHS IN THE LOWER-MID 40S EXPECTED
ACROSS SRN ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 459 AM EST WEDNESDAY...CHANCES FOR SNOW WILL TAPER OFF
TONIGHT...BUT AN ADDITIONAL INCH OR TWO IS POSSIBLE OVER NORTH
CENTRAL AND NORTHEAST VERMONT BEFORE IT WINDS DOWN BY AROUND
MIDNIGHT. EXPECT PLENTY OF CLOUDS HOWEVER... ESPECIALLY NORTH.
LOOK FOR MIN TEMPS IN THE UPPER TEENS TO MID 20S.
THURSDAY WILL BE QUIET AS SURFACE HIGH SLIDES EAST ACROSS THE REGION
AND REACHES THE EAST COAST BY EVENING. EXPECT A DECREASE IN CLOUD
COVER IN THE MORNING...FOLLOWED BY AN INCREASE IN CLOUDS AGAIN
LATER IN THE DAY IN ADVANCE OF NEXT AREA OF LOW PRESSURE
AND ASSOCIATED FRONTAL SYSTEM. IT SHOULD REMAIN MOSTLY DRY THROUGH
THE DAYLIGHT HOURS HOWEVER. WINDS TURN INTO THE SOUTH IN BETWEEN
DEPARTING HIGH AND APPROACHING LOW. WITH 850 MB TEMPS CLIMBING TO
NEAR 0C BY 00Z FRIDAY...WE CAN EXPECT A RATHER MILD DAY WITH HIGHS
IN THE MID 30S TO AROUND 40.
STRONG/HIGH AMPLITUDE MID-LEVEL TROUGH ACROSS THE CENTRAL
MISSISSIPPI VALLEY THURSDAY NIGHT RESULTS IN RAPIDLY DEEPENING LOW
PRESSURE ACROSS THE GREAT LAKES REGION (968MB PER 00Z GFS AT 12Z
FRIDAY OVER LAKE SUPERIOR). STRONG SOUTHERLY LOW-LEVEL JET DEVELOPS
DURING THURSDAY NIGHT...WITH 55-60 KTS AT 850MB BY DAYBREAK FRIDAY.
STRONG WARM FRONTAL ASCENT WILL BRING STRATIFORM PRECIPITATION TO
THE REGION...ESPECIALLY AFTER MIDNIGHT THURSDAY NIGHT.
PRECIPITATION TYPE WILL BE AN ISSUE ACROSS MUCH OF THE AREA THURSDAY
NIGHT. ABOVE FREEZING TEMPS LIKELY IN THE CHAMPLAIN VALLEY
SUPPORTING MAINLY RAIN...ALTHOUGH SOME EVAPORATIONAL COOLING AT
ONSET OF PRECIPITATION MAY SUPPORT A BRIEF PERIOD OF SLEET AND SNOW.
MODEL SOUNDINGS INDICATE THAT TEMPS ACROSS THE REST OF THE FORECAST
AREA WILL BE BELOW FREEZING NEAR THE SURFACE WITH FAVORABLE
PROFILES FOR A PERIOD OF SLEET AND POSSIBLE FREEZING RAIN. LOOK FOR
ANY ICING TO BE MINIMAL AND OF SHORT DURATION OVER MUCH OF THE
ADIRONDACKS AND SAINT LAWRENCE VALLEY. EAST OF THE GREEN
MOUNTAINS...SOME AREAS WILL SEE THE THREAT OF FREEZING RAIN LINGER
INTO MID MORNING FRIDAY AS TEMPS STRUGGLE TO CLIMB ABOVE FREEZING IN
THE SHELTERED VALLEYS. THIS MAY RESULT IN SOME TRAVEL IMPACT
DURING THE PRE-DAWN HRS INTO THE EARLY MORNING COMMUTE ON FRIDAY.
ALSO LOOKING AT LOCALLY STRONG AND GUSTY WINDS...ESPECIALLY ALONG
THE WESTERN SLOPES WHERE GUSTS MAY TOP 40 MPH FOR A TIME. THESE
WINDS WILL SHIFT TO THE SOUTHWEST WITH FRONTAL PASSAGE FROM LATE
FRIDAY MORNING THROUGH AFTERNOON ACROSS THE AREA...WITH STRONGEST
WINDS POST FROPA OVER SAINT LAWRENCE VALLEY.
AS FOR THE PRECIPITATION...THE WARM AIR ADVECTION RAIN/FREEZING RAIN
WILL BE LATE THURSDAY NIGHT THROUGH EARLY FRIDAY. MAYBE A BRIEF LULL
IN THE PRECIPITATION BEFORE MORE CONVECTIVE TYPE SHOWERS ASSOCIATED
WITH COLD FRONT QUICKLY OVERSPREAD THE REGION FROM WEST TO EAST.
EXPECT FROPA IN SAINT LAWRENCE VALLEY BY 15Z FRIDAY AND IN
EASTERN VERMONT BY AROUND 21Z. THIS PRECIPITATION EXPECTED TO BE
ALL IN THE FORM OF RAIN WITH MAX TEMPS RANGING FROM THE UPPER 30S
EASTERN VERMONT TO THE UPPER 40S IN ACROSS NORTHERN NEW YORK AND
SOUTHWEST VERMONT. PRECIPITATION TOTALS FROM THURSDAY NIGHT
THROUGH FRIDAY EXPECTED TO RANGE FROM ONE HALF TO ONE INCH...WITH
SOME LOCALLY HIGHER AMOUNTS POSSIBLE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 459 AM EST WEDNESDAY...AFTER A PRETTY ACTIVE WEEK THE
WEATHER TURNS A BIT MORE QUIET FOR THE EXTENDED PORTION OF THE
FORECAST FROM FRIDAY NIGHT ONWARD. A FAIRLY BROAD AND SOMEWHAT
FLAT UPPER TROUGH SETTLES IN OVER MUCH OF THE NORTHERN CONUS WITH
A FAST WESTERLY FLOW ALOFT ALLOWING SEVERAL WEAK SHORTWAVE
TROUGHS TO QUICKLY TRAVERSE THE AREA. THE RESULT WILL BE ON AND
OFF LOW CHANCES FOR SOME LIGHT SNOW SHOWERS...BUT NO BIG SYSTEMS
WITH VERY LITTLE OVERALL QPF. TEMPS WILL RUN NORMAL TO SLIGHTLY
ABOVE FRIDAY NIGHT THROUGH SUNDAY WITH LOWS IN THE TEENS TO MID
20S...HIGHS SATURDAY IN THE MID 30S TO MID 40S...AND SUNDAY IN
THE MID 20S TO MID 30S. FROM SUNDAY NIGHT THROUGH THE END OF THE
PERIOD THE TREND WILL BE BACK TOWARDS BELOW NORMAL TEMPS THOUGH
WITH LOWS IN THE SINGLE DIGITS TO TEENS...AND HIGHS IN THE TEENS
TO LOWER 20S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...IFR CONDITIONS WL OCCUR AT RUT/MPV THRU 21Z
TODAY...WITH POTENTIAL IFR CIGS/VIS DEVELOPING AT SLK BY 23Z THIS
EVENING. CRNT RADAR SHOWS BAND OF MODERATE SNOW LIFTING ACRS
CENTRAL/SOUTHERN VT...IMPACTING MPV/RUT WITH VIS BLW 1SM. BASED ON
RAP13 AND HRRR MODEL PROGGED COMPOSITE REFLECTIVITY EXPECT THIS
ACTIVITY TO BE EAST OF OUR TAF SITES BY 21Z WITH MAINLY MVFR
CONDITIONS PREVAILING. AT SLK THINKING WEAK SFC TROF WL SHIFT THE
WINDS TO THE WEST/NORTHWEST THIS EVENING WITH LLVL CLOUDS AND
LIGHT SNOW DEVELOPING. THIS WL RESULT IN A PERIOD OF IFR
CONDITIONS AT SLK WITH VIS BLW 2SM AND CIGS BLW OVC 1000 FT.
ELSEWHERE...EXPECTING MAINLY VFR WITH BRIEF PERIODS OF MVFR AT
MSS/BTV THRU THIS EVENING. WEAK SFC RIDGE WITH VFR CONDITIONS WL
PREVAIL LATE TONIGHT INTO 18Z WEDS AT OUR TAF SITES.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
VFR CONDITIONS WITH THICKENING CLOUDS THRU 00Z FRIDAY. SFC WARM
FRNT WL RESULT IN MIXED PRECIP DEVELOPING BY 06Z FRIDAY WITH SOME
ICE ACCUMULATION POSSIBLE AT MPV...ALONG WITH WIDESPREAD MVFR/IFR
CONDITIONS LIKELY BTWN 06Z-12Z FRIDAY. ANOTHER BAND OF MAINLY RAIN
SHOWERS OCCURS FRIDAY WITH MVFR CONDITIONS...WITH EXCEPTION OF IFR
POSSIBLE AT MSS/SLK/MPV. ALSO...WITH WARM TEMPS MOVING OVER
RELATIVELY COLD SFC TEMPS/SNOWPACK AREAS OF FOG/BR WL BE POSSIBLE
IN THE DEEPER PROTECTED VALLEY LOCATIONS OF VT/NY FRIDAY INTO
SATURDAY. STRONG LLVL JET WL RESULT IN AREAS OF LLVL WS ON
FRIDAY...ESPECIALLY AT MSS WITH NORTHEAST SFC WINDS AND SW WINDS
ALOFT AT 1500 FEET AND AT MPV WITH LIGHT SFC WINDS ANTICIPATED AND
STRONG 1000 AGL WINDS OF 45 TO 50 KNTS. GUSTY SE WINDS OF 30 TO 35
KNTS WL BE POSSIBLE AT RUTLAND ON FRIDAY MORNING...WHICH WL SHIFT
TO THE SOUTHWEST AND BECM GUSTY AT MSS/SLK/PBG/BTV DURING THE
AFTN/EVENING OF FRIDAY. OTHERWISE...DRY SLOT WL RESULT IN VFR
CONDITIONS DEVELOPING FRIDAY NIGHT AND PREVAILING INTO SUNDAY.
&&
.EQUIPMENT...
DAMAGED EQUIPMENT HAS RESULTED IN AN AUDIBLE HUM ON THE MOUNT
ASCUTNEY NOAA WEATHER RADIO BROADCAST (WXM-44). OUR TECHNICIANS
ARE AWARE OF THE PROBLEM AND WILL RESOLVE THE ISSUE AS QUICKLY AS
POSSIBLE. REPAIRS MAY INVOLVE COORDINATION AND ACCESS BY
TELCO...INCLUDING PARTS ACQUISITION. THIS MAY TAKE 1-2 DAYS TO
RESOLVE. IN THE MEANTIME...WE APOLOGIZE FOR ANY DIFFICULTIES IN
HEARING THE BROADCAST FROM MOUNT ASCUTNEY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS/RJS
NEAR TERM...BANACOS
SHORT TERM...RJS
LONG TERM...LAHIFF
AVIATION...TABER
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
636 AM EST WED FEB 19 2014
.SYNOPSIS...
A STORM SYSTEM MOVING ACROSS LAKE ERIE WILL BRING A WARM UP TO OUR
REGION TODAY AND THURSDAY. A STRONGER STORM WILL MOVE FROM THE
MIDWEST INTO LOWER CANADA THURSDAY NIGHT, BRINGING RAIN AND
ADDITIONAL WARM AIR TO NY AND PA.
&&
.NEAR TERM /THROUGH TONIGHT/...
STORM SYSTEM AND SHORTWAVE TRACKING ACROSS GREAT LAKES WILL BRING
PRECIPITATION TO OUR REGION THIS MORNING. TEMPERATURES FELL INTO
THE TEENS AND LOWER 20S, BUT HAVE ALREADY BEGUN TO STABILIZE AND
RISE IN SOME SPOTS. AS SOUTHERLY FLOW INCREASES AHEAD OF THE
APPROACHING STORM, TEMPERATURES WILL ACCELERATE UPWARD.
THERE ARE TWO BIG PROBLEMS WITH THE CURRENT FREEZING RAIN
SCENARIO. THE FIRST IS THAT THE ATMOSPHERE REMAINS VERY DRY, AND
THE RADAR IS VERY QUIET BACK INTO WESTERN PA AND EASTERN OHIO.
CONVECTIVE ELEMENTS HAVE FIRED OVER SOUTHERN OHIO, BUT RADAR
TRAJECTORY WOULD SUGGEST THEY WILL PASS WELL SOUTH OF OUR FA.
UPGLIDE SHOULD PRODUCE PRECIP FORMATION THIS MORNING, BUT THE
TIMING WILL LIKELY BE BETWEEN 13Z AND 15Z WHEN TEMPERATURES WILL
BE PUSHING NORTH OF 32F. LATEST RUC AND HRRR HAVE SUGGESTED BIG
REDUCTIONS IN QPF/POPS OVER THE FIRST HALF OF THE DAY, WHEN THE
FREEZING RAIN POTENTIAL EXISTS.
WE MAY NEED TO RECONSIDER THE ADVISORY. AT THIS POINT WE WILL LET
IT RIDE, AND HOPEFULLY HAVE A CLEAR ENOUGH RADAR PICTURE BY 5 AM
OR SO THAT WE CAN LEAVE NEXT SHIFT WITH A CONFIDENT FORECAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A RIDGE REBUILDS TONIGHT INTO THURSDAY, ALLOWING FOR AN OVERNIGHT
COOL DOWN BEFORE TEMPERATURES PUSH INTO THE 40S THURSDAY.
A VIGOROUS CYCLONE WILL ROTATE OUT OF THE MIDWEST INTO LOWER
CANADA THURSDAY NIGHT, DRAGGING A WARM FRONT ACROSS LAKE ERIE. DEW
POINTS WILL ALSO INCREASE, AND THERE IS THE POTENTIAL FOR SOME
OVERNIGHT FOG, WHICH IS AN EFFECTIVE SNOW PACK MELTER.
THE COMBINATION OF RUN OFF AND QPF IS NOT TOO ALARMING IN THIS
CASE, AND I WOULD NOT BE SURPRISED IF A LOT OF THE QPF IS ABSORBED
IN THE STILL THICK SNOW PACK.
THE MAIN RISK APPEARS TO BE FOR ICE BREAKING UP ON AREA STREAMS AND
CREEKS. THIS WOULD LEAD TO HIGHLY LOCALIZED ICE JAM ISSUES, MAKING
A WIDESPREAD FFA OVERKILL. WITH THIS EVENT STILL A SOLID 42 TO 54
HOURS OUT, SEE TOO MUCH RISK IN RUSHING IN WITH A FLAG THIS EARLY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FRIDAY NIGHT THE SFC LOW AND ATTENDANT RAIN SHOWERS ARE EXPECTED TO
MOVE NORTH OF THE REGION AND A BRIEF DRY PERIOD WILL RETURN THROUGH
SATURDAY AFTERNOON. ANOTHER COLD FRONT IS EXPECTED TO MOVE THROUGH
THE CWA LATE SAT NIGHT/SUN MORNING BRINGING ANOTHER SHOT OF SNOW
SHOWERS AND COLDER AIR. COLD AIR WILL CONTINUE TO ADVECT INTO THE
REGION AND BY MONDAY MORNING AND 850MB TEMPS WILL FALL TO AROUND
NEGATIVE 18 DEGREES... THUS WE MAY SEE A WEAK LAKE EFFECT RESPONSE
AND SCATTERED SNOW SHOWERS MAY DEVELOP ACROSS THE REGION THROUGH
TUESDAY MORNING. A SFC RIDGE WILL START TO BUILD INTO THE REGION
TUES MORNING FROM THE SW WHICH WILL RESULT IN THE LAKE EFFECT
RESPONSE TO DIMINISH. AFTER TUESDAY GUIDANCE STARTS TO VARY
GREATLY BETWEEN EACH OTHER... AND DECIDED TO JUST KEEP 20 PERCENT
POPS ATTM AS AN ACTIVE PATTERN IS EXPECTED IN THE FAR EXTENDED AND
CONFIDENCE IS LOW ON WHICH MODEL TO FOLLOW.
DECIDED TO GO CLOSELY WITH WPC GUIDANCE WITH TEMPS THROUGH THE
EXTENDED. SAT TEMPS WILL STILL REMAIN IN THE UPR 30S TO MID 40S AS
THE COLD FRONT WONT MOVE THROUGH THE REGION UNTIL LATE SAT NIGHT.
SUNDAY THE COLD AIR WILL RETURN AND WINTER WILL MAKE ITS MARK YET
ONCE AGAIN. TUESDAY MORNING WILL BE PARTICULARLY COLD WITH LOWS
ACROSS CENTRAL NY AND NORTHEAST PA BEING IN THE SINGLE DIGITS.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
STRONG LTL SHRT WV AND SFC WV HAS DVLPD A CONCENTRATED AREA OF
PCPN OVER CNTRL PA THAT IS ZIPPING EAST THIS MRNG. THE MAJORITY OF
THIS PCPN WILL MISS THE NY SITES BUT WILL GIVE A BRIEF PD OF FZRA
TO AVP...AND PERHAPS BGM. OTRW...LGT PCPN WILL DVLP OVER THE NY
STATIONS AS THE LOW MVES NE TODAY RESULTING IN MAINLY MVFR CIGS
AND VSBYS. DRIER AIR MVES IN LTR THIS AFTN AND OVRNGT RETURNING
VFR CIGS AND VSBYS OVRNGT...WITH THE XCPTN OF RME WHERE SOME LAKE
MOISTURE MAY KEEP LWR CIGS.
OUTLOOK...
THU AFTN...POSSIBLE RESTRICTIONS IN MIXED PRECIP.
THU NGT...MVFR/IFR RESTRICTIONS POSSIBLE IN FOG/RAIN.
FRI...RESTRICTIONS POSSIBLE IN -RA.
SAT/SUN...MVFR/IFR RESTRICTIONS POSSIBLE IN SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR PAZ038>040-043-
044-047-048-072.
NY...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR NYZ022>025-044-
045-055>057-062.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP
SHORT TERM...DJP
LONG TERM...KAH
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
245 AM EST WED FEB 19 2014
.SYNOPSIS...
A STORM SYSTEM MOVING ACROSS LAKE ERIE WILL BRING A WARM UP TO OUR
REGION TODAY AND THURSDAY. A STRONGER STORM WILL MOVE FROM THE
MIDWEST INTO LOWER CANADA THURSDAY NIGHT, BRINGING RAIN AND
ADDITIONAL WARM AIR TO NY AND PA.
&&
.NEAR TERM /THROUGH TODAY/...
STORM SYSTEM AND SHORTWAVE TRACKING ACROSS GREAT LAKES WILL BRING
PRECIPITATION TO OUR REGION THIS MORNING. TEMPERATURES FELL INTO
THE TEENS AND LOWER 20S, BUT HAVE ALREADY BEGUN TO STABILIZE AND
RISE IN SOME SPOTS. AS SOUTHERLY FLOW INCREASES AHEAD OF THE
APPROACHING STORM, TEMPERATURES WILL ACCELERATE UPWARD.
THERE ARE TWO BIG PROBLEMS WITH THE CURRENT FREEZING RAIN
SCENARIO. THE FIRST IS THAT THE ATMOSPHERE REMAINS VERY DRY, AND
THE RADAR IS VERY QUIET BACK INTO WESTERN PA AND EASTERN OHIO.
CONVECTIVE ELEMENTS HAVE FIRED OVER SOUTHERN OHIO, BUT RADAR
TRAJECTORY WOULD SUGGEST THEY WILL PASS WELL SOUTH OF OUR FA.
UPGLIDE SHOULD PRODUCE PRECIP FORMATION THIS MORNING, BUT THE
TIMING WILL LIKELY BE BETWEEN 13Z AND 15Z WHEN TEMPERATURES WILL
BE PUSHING NORTH OF 32F. LATEST RUC AND HRRR HAVE SUGGESTED BIG
REDUCTIONS IN QPF/POPS OVER THE FIRST HALF OF THE DAY, WHEN THE
FREEZING RAIN POTENTIAL EXISTS.
WE MAY NEED TO RECONSIDER THE ADVISORY. AT THIS POINT WE WILL LET
IT RIDE, AND HOPEFULLY HAVE A CLEAR ENOUGH RADAR PICTURE BY 5 AM
OR SO THAT WE CAN LEAVE NEXT SHIFT WITH A CONFIDENT FORECAST.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
A RIDGE REBUILDS TONIGHT INTO THURSDAY, ALLOWING FOR AN OVERNIGHT
COOL DOWN BEFORE TEMPERATURES PUSH INTO THE 40S THURSDAY.
A VIGOROUS CYCLONE WILL ROTATE OUT OF THE MIDWEST INTO LOWER
CANADA THURSDAY NIGHT, DRAGGING A WARM FRONT ACROSS LAKE ERIE. DEW
POINTS WILL ALSO INCREASE, AND THERE IS THE POTENTIAL FOR SOME
OVERNIGHT FOG, WHICH IS AN EFFECTIVE SNOW PACK MELTER.
THE COMBINATION OF RUN OFF AND QPF IS NOT TOO ALARMING IN THIS
CASE, AND I WOULD NOT BE SURPRISED IF A LOT OF THE QPF IS ABSORBED
IN THE STILL THICK SNOW PACK.
THE MAIN RISK APPEARS TO BE FOR ICE BREAKING UP ON AREA STREAMS AND
CREEKS. THIS WOULD LEAD TO HIGHLY LOCALIZED ICE JAM ISSUES, MAKING
A WIDESPREAD FFA OVERKILL. WITH THIS EVENT STILL A SOLID 42 TO 54
HOURS OUT, SEE TOO MUCH RISK IN RUSHING IN WITH A FLAG THIS EARLY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FRIDAY NIGHT THE SFC LOW AND ATTENDANT RAIN SHOWERS ARE EXPECTED TO
MOVE NORTH OF THE REGION AND A BRIEF DRY PERIOD WILL RETURN THROUGH
SATURDAY AFTERNOON. ANOTHER COLD FRONT IS EXPECTED TO MOVE THROUGH
THE CWA LATE SAT NIGHT/SUN MORNING BRINGING ANOTHER SHOT OF SNOW
SHOWERS AND COLDER AIR. COLD AIR WILL CONTINUE TO ADVECT INTO THE
REGION AND BY MONDAY MORNING AND 850MB TEMPS WILL FALL TO AROUND
NEGATIVE 18 DEGREES... THUS WE MAY SEE A WEAK LAKE EFFECT RESPONSE
AND SCATTERED SNOW SHOWERS MAY DEVELOP ACROSS THE REGION THROUGH
TUESDAY MORNING. A SFC RIDGE WILL START TO BUILD INTO THE REGION
TUES MORNING FROM THE SW WHICH WILL RESULT IN THE LAKE EFFECT
RESPONSE TO DIMINISH. AFTER TUESDAY GUIDANCE STARTS TO VARY
GREATLY BETWEEN EACH OTHER... AND DECIDED TO JUST KEEP 20 PERCENT
POPS ATTM AS AN ACTIVE PATTERN IS EXPECTED IN THE FAR EXTENDED AND
CONFIDENCE IS LOW ON WHICH MODEL TO FOLLOW.
DECIDED TO GO CLOSELY WITH WPC GUIDANCE WITH TEMPS THROUGH THE
EXTENDED. SAT TEMPS WILL STILL REMAIN IN THE UPR 30S TO MID 40S AS
THE COLD FRONT WONT MOVE THROUGH THE REGION UNTIL LATE SAT NIGHT.
SUNDAY THE COLD AIR WILL RETURN AND WINTER WILL MAKE ITS MARK YET
ONCE AGAIN. TUESDAY MORNING WILL BE PARTICULARLY COLD WITH LOWS
ACROSS CENTRAL NY AND NORTHEAST PA BEING IN THE SINGLE DIGITS.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
SHRT WV ZIPPING THRU THE OH VLY AND GREAT LAKES WILL BRING CLDS
AND MIXED PCPN TO THE AREA AFT 12Z WED. TEMPS ARE VERY MRGNL SO
EXACT PCPN TYPE DFCLT TO FCST...BUT IT DOES APPEAR THAT AT LEAST
OCNL IFR CONDS DUE TO VSBY PSBL FOR SVRL HRS WED. SFC TROF PASSES
AND COLDER AIR MVES IN BHD THE SYSTEM LTR WED BRINGING VFR CONDS.
OUTLOOK...
WED OVERNIGHT TO THU MORN...VFR.
THU AFTN...POSSIBLE RESTRICTIONS IN MIXED PRECIP.
THU NGT...MVFR/IFR RESTRICTIONS POSSIBLE IN FOG/RAIN.
FRI...RESTRICTIONS POSSIBLE IN -RA.
SAT/SUN...MVFR/IFR RESTRICTIONS POSSIBLE IN SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FREEZING RAIN ADVISORY FROM 7 AM THIS MORNING TO NOON EST
TODAY FOR PAZ038>040-043-044-047-048-072.
NY...FREEZING RAIN ADVISORY FROM 7 AM THIS MORNING TO NOON EST
TODAY FOR NYZ022>025-044-045-055>057-062.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP
SHORT TERM...DJP
LONG TERM...KAH
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
411 AM EST WED FEB 19 2014
.SYNOPSIS...
WEAK COLD FRONT PUSHES EXITS EAST EARLY TODAY. VIGOROUS SYSTEM
PASSES THURSDAY NIGHT...BUT MILD...PACIFIC AIR FOLLOWS IT AS WELL.
COLD FRONT CROSSES SATURDAY NIGHT,..BEGINNING A TREND TO COLDER.
&&
.NEAR TERM /THROUGH TODAY/...
COLD FRONT MOVING ACROSS THIS MORNING...WITH FEW STORMS EMBEDDED
WITHIN RAIN SHOWERS. INCREASED POPS WITH THIS FEATURE...DECREASING
THEM TO LIKELIES BY THE TIME PCPN REACHES THE MOUNTAINS. USED THE
RAP MODELS FOR POPS TWEAKING THEM DOWN SOME.
EXPECT THE FRONT TO EXIT THE EASTERN MOUNTAINS LATER THIS MORNING
OR EARLY AFTERNOON ENDING CHANCES FOR PCPN. NO SIGNIFICANT PCPN IS
EXPECTED ATTM. UPPER SHELTERED VALLEYS WHERE TEMPERATURES ARE
BELOW FREEZING...FREEZING RAIN WILL BE POSSIBLE FOR A SHORT PERIOD
OF TIME DURING THE PREDAWN HOURS.
BRING POPS BACK FROM THE SOUTH EARLY LATE TONIGHT INTO EARLY
THURSDAY MORNING AS A WARM FRONT LIFT NORTH ACROSS THE AREA.
SOUTHWEST FLOW BRING WARMER TEMPERATURES TO THE AREA.
GENERALLY...TEMPS SHOULD REACH THE UPPER 50S LOWLANDS...RANGING
INTO THE MID 40S NORTHEAST MOUNTAINS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
SPRING SPRINGS THIS PERIOD AS STRONG S FLOW AHEAD OF A VIGOROUS S/W
TROUGH / SFC COLD FRONT BRINGS A RATHER MILD THU...FOLLOWED BY THE
THREAT FOR STRONG THUNDERSTORMS THU EVENING.
BUBBLE HIGH EXITS WED EVENING...ALLOWING STRENGTHENING FLOW FROM THE
S AHEAD OF THE NEXT SYSTEM. WARM FRONT ASSOCIATED WITH THIS SYSTEM
MOVES NWD THROUGH THE AREA EARLY THU MORNING THROUGH THE DAY THU.
ELEVATED INSTABILITY IN THE POSITIVE THETA E ADVECTION COULD LEAD TO
THUNDER AHEAD OF AND ALONG THE WARM FRONT AS PW VALUES CLIMB TO
AROUND AN INCH AND SHOWALTERS GO TO ZERO.
WARM SECTOR BECOMES ESTABLISHED BY THU EVENING...BEFORE COLD FRONT
COMES CHARGING THROUGH OVERNIGHT. PW VALUES GET AS HIGH AS ABOUT
1.25 IN AS SFC DEW POINTS APPROACH 50 AND H85 WIND INCREASE TO 70
KTS OR BETTER. INSTABILITY AXIS JUST AHEAD OF THE COLD FRONT WANES
AS IT CROSSES THE AREA THU NT BUT...GIVEN THE STRONG FLOW
ALOFT...ANY CONVECTIVE LINE THAT GETS GOING UPSTREAM CAN MAINTAIN A
DAMAGING WIND THREAT AT LEAST AS FAR E AS THE E EDGE OF THE SLIGHT
RISK AREA...WHICH CUTS N-S THROUGH HTS...WITH STRONG GUSTS POSSIBLE
WELL E OF THERE. THE RUC WIND GUST MOMENTUM ALGORITHM YIELDS GUSTS
TO 40 KTS OVER THE HIGH TERRAIN AND UP TO 30 KTS OVER THE
LOWLANDS...SO IT WILL TAKE HEAVY SHOWERS...OR THUNDERSTORMS...TO
BRING THE GREATER MOMENTUM DOWN. THE HWO ALREADY CARRIES A SEVERE
THREAT IN THE SLIGHT RISK AREA PER PREVIOUS SHIFT.
USED GFS/NAM BLEND FOR QPF WHICH IS UP NEAR AN INCH IN THE
W...DIMINISHING TO AS LITTLE AS A QUARTER OF AN INCH IN THE
MOUNTAINS...WAY TO LITTLE TO RELEASE THE SNOW PACK EVEN WITH STRONG
WINDS AND DEW POINTS ABOVE FREEZING. THE CANADIAN IS AN ODD MODEL
OUT IN NOT PUSHING THE COLD FRONT THROUGH UNTIL FRI MORNING.
IT APPEARS THE COLD ADVECTION BEHIND THIS COLD FRONT WILL BE TOO
WEAK TO COUNTER DIURNAL HEATING FRI...AS TEMPERATURES WILL RECOVER
TO HIGHS ABOVE NORMAL. A BUBBLE HIGH OF PACIFIC ORIGIN PASSES S OF
THE AREA FRI AFTERNOON...AS LOW PRESSURE INTENSIFIES OVER SERN
CANADA. THE GRADIENT BETWEEN THESE TWO FEATURES WILL PRODUCE STRONG
WINDS...ESPECIALLY ACROSS THE N...WHERE THE MOMENTUM ALGORITHM PUMPS
OUT GUSTS AROUND 30 KTS.
BLENDED IN GFS-BASED BIAS CORRECTED MOS FOR HIGHS AND NAM12 AND THE
MET FOR NON-DIURNAL TEMPERATURES BOTH NTS...OVERALL LITTLE CHANGE
FROM PREVIOUS FCST SAVE FOR TIMING OF COLDER AIR THU NT...A LITTLE
LATER.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
MODELS SHOWING COLD AIR MOVING BACK INTO THE REGION LATE THIS
WEEKEND. BOTH THE ECMWF AND GFS SHOWING A POTENTIAL ENHANCED CLIPPER
SNOW EARLY NEXT WEEK. HOWEVER...LOTS OF DIFFERENCES IN THE ENSEMBLE
MEMBERS ON THE TIMING OF FEATURES...EVEN THOUGH ENSEMBLES SUPPORT
THE BROADER PATTERN WITH A TROUGH IN THE EAST. THEREFORE...USED THE
ECMWF AND GEFS MEANS...AS CONFIDENCE WITH INDIVIDUAL ENERGY PIECES
IS LOW.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
WIDESPREAD VFR CONDITIONS WILL PREVAIL THROUGH AT LEAST 09Z.
THEN...CONVECTION WILL ENTER SOUTHEAST OH...NORTHEAST KY TO SPREAD
ACROSS WV DURING THE PREDAWN HOURS. INTRODUCED SPATIAL AND TIMING DETAILS
FROM THE HIGH RESOLUTION RAP MODEL WHICH INITIALIZED WELL WITH
RADAR IMAGES.
PRECIPITATION WILL BE IN THE FORM OF -RA...AND WITH A LIGHTNING OR
TWO POSSIBLE. EXPECT BRIEF MVFR CONDITIONS BETWEEN 06Z-18Z
WEDNESDAY IN PRECIPITATION. FLOW AT H85 FROM THE SOUTHWEST ABOUT
40 KNOTS NOT IMPRESSIVE...AND THE ATMOSPHERE SHOULD CONTINUE
DECOUPLED THROUGH AT LEAST 12Z. FLOW BECOMES GUSTY UP TO 35 KTS
ACROSS HIGHER TERRAIN...AND UP TO 22 KTS ACROSS LOWLANDS.
AREAS OF RAIN WILL START CLEARING FROM WEST TO EAST BY EARLY
AFTERNOON...TO AFFECT EKN AND BKW THE LATEST THROUGH AT LEAST 21Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF THE ONSET OF PRECIPITATION AND MVFR
PREVALENT CIGS MAY VARY...AND IMPROVEMENT TO VFR MAY ALSO VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE WED 02/19/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY H H L L L L L L H H H H
HTS CONSISTENCY L L L L L L L L H H H H
BKW CONSISTENCY H L L L L L L L L M M H
EKN CONSISTENCY H H H M M L L L L L L L
PKB CONSISTENCY H L L L L L L L L L L L
CKB CONSISTENCY H H H L L L L L L L L L
AFTER 06Z THURSDAY...
IFR POSSIBLE THURSDAY NIGHT IN GUSTY SHOWERS...AND POSSIBLY A STRONG
THUNDERSTORM.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...ARJ
SHORT TERM...50
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
103 AM EST WED FEB 19 2014
.SYNOPSIS...
WEAK COLD FRONT PUSHES EAST OVERNIGHT. VIGOROUS SYSTEM PASSES
THURSDAY NIGHT...BUT MILD...PACIFIC AIR FOLLOWS IT AS WELL. A COLD
FRONT CROSSES SATURDAY NIGHT,...BEGINNING A TREND TO COLDER.
&&
.NEAR TERM /THROUGH TODAY/...
SENT AN UPDATE TO ADJUST POPS ACCORDING TO THE RAP HIGH RESOLUTION
MODEL WHICH SHOW BETTER INITIALIZATION AMONG OTHER MODELS
DEVELOPING CONVECTION ASSOCIATED WITH UPCOMING COLD FRONT ACROSS
SOUTHERN OH ...AND KENTUCKY. THIS CONVECTION IS EXPECTED TO REACH
OUR SOUTHEAST OH COUNTIES AROUND 08-09Z. THEN SPREAD EAST TO COVER
MOST PART OF THE AREA.
VERY ISOLATED LIGHTNING HAVE BEEN REPORTED UPSTREAM THIS
CONVECTION. EXPECT ANY STORM TO BE SHORT LIVED...BUT PRODUCE
BRIEF PERIODS OF MODERATE RAINFALL AND SOME STRONG GUSTY WINDS.
PREVIOUS DISCUSSION BELOW...
915 PM UPDATE...NO MAJOR CHANGES NEEDED TO PREVIOUS FORECAST.
PREVIOUS DISCUSSION FOLLOWS...
THE SYSTEM THAT PRODUCED THE PRECIPITATION LAST NIGHT HAS PUSHED
WELL TO OUR EAST...WITH WEAK HIGH PRESSURE NOW IN CONTROL OF THE
REGION. THE COMBINATION OF ABUNDANT SUNSHINE AND GUSTY SOUTHWESTERLY
WINDS HAVE PUSHED TEMPERATURES INTO THE MID 40S TO MID 50S ACROSS
MUCH OF THE AREA.
THE HIGH WILL PUSH EAST TONIGHT...ALLOWING A COLD FRONT TO
APPROACH FROM THE WEST. EXPECT CLOUDS WILL INCREASE...WITH
PRECIPITATION EXPECTED TO SPREAD NORTHEAST ACROSS THE AREA AFT 06
UTC.
THE COLD FRONT WILL PUSH EAST ON WEDNESDAY...BRINGING THE
PRECIPITATION CHANCES TO AN END.
WITH NAM/GFS AS WELL AS WPC ALL INDICATING MEASURABLE
PRECIPITATION...HAVE BUMPED POPS TO LIKELY...ALONG AND AHEAD OF THE
FRONT. LOOKS LIKE THIS WILL BE A HIGH POP...LOW QPF EVENT.
LATEST TEMP GUIDANCE SUGGESTS LOW TEMP FORECAST FOR TONIGHT AND
HIGHS ON WEDNESDAY ARE IN THE BALLPARK...SO HAVE ONLY MADE SOME
MINOR TWEAKS.
WITH WARMING TEMPS ALOFT AND MOST OF THE REGION SHOULD BE ABOVE
FREEZING AT THE SURFACE...RAIN SHOULD BE THE PREDOMINANT WEATHER
TYPE.
INITIALLY THOUGHT SOME OF THE SHELTERED NORTHERN MOUNTAIN VALLEYS
WILL BE COLD ENOUGH FOR THE PRECIPITATION TO BE IN THE FORM OF
FREEZING RAIN. BUT IT NOW LOOKS LIKE TEMPERATURES WILL FALL
EARLY...AND THEN WARM AS THE CLOUDS AND PRECIPITATION MOVE IN.
MAY BE SOME ISOLATED LOCATIONS THAT COULD SEE FREEZING RAIN...BUT IT
SHOULD NOT LAST LONG...AND BE VERY LIGHT. WITH THIS CHANGE...DO NOT
THINK THERE IS THE NEED FOR ANY FREEZING RAIN ADVISORIES.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
SPRING SPRINGS THIS PERIOD AS STRONG S FLOW AHEAD OF A VIGOROUS S/W
TROUGH / SFC COLD FRONT BRINGS A RATHER MILD THU...FOLLOWED BY THE
THREAT FOR STRONG THUNDERSTORMS THU EVENING.
BUBBLE HIGH EXITS WED EVENING...ALLOWING STRENGTHENING FLOW FROM THE
S AHEAD OF THE NEXT SYSTEM. WARM FRONT ASSOCIATED WITH THIS SYSTEM
MOVES NWD THROUGH THE AREA EARLY THU MORNING THROUGH THE DAY THU.
ELEVATED INSTABILITY IN THE POSITIVE THETA E ADVECTION COULD LEAD TO
THUNDER AHEAD OF AND ALONG THE WARM FRONT AS PW VALUES CLIMB TO
AROUND AN INCH AND SHOWALTERS GO TO ZERO.
WARM SECTOR BECOMES ESTABLISHED BY THU EVENING...BEFORE COLD FRONT
COMES CHARGING THROUGH OVERNIGHT. PW VALUES GET AS HIGH AS ABOUT
1.25 IN AS SFC DEW POINTS APPROACH 50 AND H85 WIND INCREASE TO 70
KTS OR BETTER. INSTABILITY AXIS JUST AHEAD OF THE COLD FRONT WANES
AS IT CROSSES THE AREA THU NT BUT...GIVEN THE STRONG FLOW
ALOFT...ANY CONVECTIVE LINE THAT GETS GOING UPSTREAM CAN MAINTAIN A
DAMAGING WIND THREAT AT LEAST AS FAR E AS THE E EDGE OF THE SLIGHT
RISK AREA...WHICH CUTS N-S THROUGH HTS...WITH STRONG GUSTS POSSIBLE
WELL E OF THERE. THE RUC WIND GUST MOMENTUM ALGORITHM YIELDS GUSTS
TO 40 KTS OVER THE HIGH TERRAIN AND UP TO 30 KTS OVER THE
LOWLANDS...SO IT WILL TAKE HEAVY SHOWERS...OR THUNDERSTORMS...TO
BRING THE GREATER MOMENTUM DOWN. THE HWO ALREADY CARRIES A SEVERE
THREAT IN THE SLIGHT RISK AREA PER PREVIOUS SHIFT.
USED GFS/NAM BLEND FOR QPF WHICH IS UP NEAR AN INCH IN THE
W...DIMINISHING TO AS LITTLE AS A QUARTER OF AN INCH IN THE
MOUNTAINS...WAY TO LITTLE TO RELEASE THE SNOW PACK EVEN WITH STRONG
WINDS AND DEW POINTS ABOVE FREEZING. THE CANADIAN IS AN ODD MODEL
OUT IN NOT PUSHING THE COLD FRONT THROUGH UNTIL FRI MORNING.
IT APPEARS THE COLD ADVECTION BEHIND THIS COLD FRONT WILL BE TOO
WEAK TO COUNTER DIURNAL HEATING FRI...AS TEMPERATURES WILL RECOVER
TO HIGHS ABOVE NORMAL. A BUBBLE HIGH OF PACIFIC ORIGIN PASSES S OF
THE AREA FRI AFTERNOON...AS LOW PRESSURE INTENSIFIES OVER SERN
CANADA. THE GRADIENT BETWEEN THESE TWO FEATURES WILL PRODUCE STRONG
WINDS...ESPECIALLY ACROSS THE N...WHERE THE MOMENTUM ALGORITHM PUMPS
OUT GUSTS AROUND 30 KTS.
BLENDED IN GFS-BASED BIAS CORRECTED MOS FOR HIGHS AND NAM12 AND THE
MET FOR NON-DIURNAL TEMPERATURES BOTH NTS...OVERALL LITTLE CHANGE
FROM PREVIOUS FCST SAVE FOR TIMING OF COLDER AIR THU NT...A LITTLE
LATER.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MODELS SHOWING COLD AIR MOVING BACK INTO THE REGION LATE THIS
WEEKEND. BOTH THE ECMWF AND GFS SHOWING A POTENTIAL ENHANCED CLIPPER
SNOW EARLY NEXT WEEK. HOWEVER...LOTS OF DIFFERENCES IN THE ENSEMBLE
MEMBERS ON THE TIMING OF FEATURES...EVEN THOUGH ENSEMBLES SUPPORT
THE BROADER PATTERN WITH A TROUGH IN THE EAST. THEREFORE...USED THE
ECMWF AND GEFS MEANS...AS CONFIDENCE WITH INDIVIDUAL ENERGY PIECES
IS LOW.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
WIDESPREAD VFR CONDITIONS WILL PREVAIL THROUGH AT LEAST 09Z.
THEN...CONVECTION WILL ENTER SOUTHEAST OH...NORTHEAST KY TO SPREAD
ACROSS WV DURING THE PREDAWN HOURS. INTRODUCED SPATIAL AND TIMING DETAILS
FROM THE HIGH RESOLUTION RAP MODEL WHICH INITIALIZED WELL WITH
RADAR IMAGES.
PRECIPITATION WILL BE IN THE FORM OF -RA...AND WITH A LIGHTNING OR
TWO POSSIBLE. EXPECT BRIEF MVFR CONDITIONS BETWEEN 06Z-18Z
WEDNESDAY IN PRECIPITATION. FLOW AT H85 FROM THE SOUTHWEST ABOUT
40 KNOTS NOT IMPRESSIVE...AND THE ATMOSPHERE SHOULD CONTINUE
DECOUPLED THROUGH AT LEAST 12Z. FLOW BECOMES GUSTY UP TO 35 KTS
ACROSS HIGHER TERRAIN...AND UP TO 22 KTS ACROSS LOWLANDS.
AREAS OF RAIN WILL START CLEARING FROM WEST TO EAST BY EARLY
AFTERNOON...TO AFFECT EKN AND BKW THE LATEST THROUGH AT LEAST 21Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF THE ONSET OF PRECIPITATION AND MVFR
PREVALENT CIGS MAY VARY...AND IMPROVEMENT TO VFR MAY ALSO VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE WED 02/19/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H L L L L L L H H
HTS CONSISTENCY H H L L L L L L L L H H
BKW CONSISTENCY H H H L L L L L L L L M
EKN CONSISTENCY H H H H H M M L L L L L
PKB CONSISTENCY H H H L L L L L L L L L
CKB CONSISTENCY H H H H H L L L L L L L
AFTER 06Z THURSDAY...
IFR POSSIBLE THURSDAY NIGHT IN GUSTY SHOWERS...AND POSSIBLY A STRONG
THUNDERSTORM.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/ARJ/TRM/RPY
NEAR TERM...JSH/ARJ/SL
SHORT TERM...TRM
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS NORMAN OK
1144 AM CST WED FEB 19 2014
.DISCUSSION...
THE 18Z AVIATION DISCUSSION FOLLOWS....
&&
.AVIATION...
A WARM FRONT WILL BRING LOW CEILINGS AND PATCHES OF BR TO MUCH OF
OK AND N TX THIS AFTERNOON. CLEARING IS EXPECTED AT MOST SITES
THIS EVENING AS WINDS SWITCH TO THE S/SW AHEAD OF AN APPROACHING
COLD FRONT. THIS COLD FRONT WILL SWEEP RAPIDLY THROUGH OK/N TX
TOMORROW MORNING. BEHIND THE FRONT...EXPECT STRONG NW
WINDS...ABOUT 25-35 KT WITH GUSTS 30-40KT...PERHAPS MORE. A BRIEF
PERIOD OF CEILINGS AROUND 2500 FT WILL LIKELY FOLLOW THE FRONT AS
WELL. WINDS SHOULD DIMINISH SOMEWHAT DURING THE AFTERNOON
TOMORROW.
&&
.PREV DISCUSSION... /ISSUED 1046 AM CST WED FEB 19 2014/
UPDATE...
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST THROUGH THIS EVENING.
HIGH RESOLUTION MODELS...INCLUDING THE HRRR AND NSSL
WRF...INDICATE THAT CHANCES FOR TSRA WILL REMAIN VERY SLIM OVER
MUCH OF THE REGION. THE ONE EXCEPTION LOOKS TO BE OVER FAR NORTH
CENTRAL/NORTHEAST OKLAHOMA...WHERE ELEVATED THUNDER APPEARS
PROBABLE. THUS...HAVE ADJUSTED POPS TO REFLECT LATER TIMING OF
POSSIBLE SHRA/TSRA AND INCLUDED HIGHER PROBS OVER KAY COUNTY
OKLAHOMA. OTHERWISE...THE FORECAST LOOKS TO BE IN DECENT SHAPE AND
ONLY UPDATED HOURLY TEMPS/DEWPOINTS/WINDS TO REFLECT RECENT OBS.
PREV DISCUSSION... /ISSUED 605 AM CST WED FEB 19 2014/
AVIATION...19 FEB 12Z TAF ISSUANCE...
EXPECT VFR CIGS TO PREVAIL THROUGH THE MORNING HOURS. DECENT MID-
HIGH DECK OF STRATUS WILL CONTINUE TO STREAM ACROSS THE REGION
TODAY AHEAD OF AN ADVANCING FRONTAL BOUNDARY. EASTERLY WINDS WILL
SLOWLY VEER OUT OF THE S/SE THROUGH THE DAY... WITH INCREASING
MOISTURE IN THE LOWER LEVELS. THIS MAY RESULT IN SOME LIGHT FOG
AND PERHAPS DRIZZLE ACROSS PORTIONS OF CENTRAL AND SRN OK... WITH
MVFR VIS AND CIGS. BIGGEST CONCERN FACING AVIATION THIS TAF PERIOD
ARE THE STRONG N/NW WINDS THAT WILL ARRIVE LATE IN THE PERIOD ACROSS
N/NWRN OK. EXPECT WINDS ANYWHERE FROM 20 TO 30 KTS... WITH GUSTS OF
40 TO 50 EXPECTED NEAR DAY BREAK ACROSS NWRN OK.
JTK
PREV DISCUSSION... /ISSUED 348 AM CST WED FEB 19 2014/
DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED ON THE IMPACTS ASSOCIATED
WITH THE STOUT SFC LOW POISED TO SWING ACROSS THE SRN/CENTRAL PLAINS
TONIGHT/EARLY THU.
CURRENTLY... THE WEAK FRONT FROM TUE EVENING REMAINS STALLED SOUTH
OF THE RED RIVER... DECENT MID 50S TO NEAR 60 DEW POINTS REMAIN
POOLED ALONG THE SFC TROUGH AXIS. WITH CALM WINDS... LIGHT FOG HAS
DEVELOPED AND WILL REMAIN LIKELY THROUGH THE MORNING ALONG THE RED
RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL OK. 09Z SFC ANALYSIS
SHOWS TEMPS HOLDING IN THE UPPER 40S AND 50S ACROSS CENTRAL AND SRN
OK AND WRN N TX WHERE WINDS REMAIN ELEVATED. EXPECT TEMPS TO LOWER A
FEW DEGREES MORE AS WINDS LESSEN SLIGHTLY THROUGH SUNRISE.
AFTER SUNRISE... EXPECT RAPID MOISTURE RETURN TO START THIS MORNING
AS ERLY SFC WINDS VEER TO THE SE THROUGH NOON AHEAD OF THE SFC
LOW/H500 TROUGH. SPEAKING OF THE TROUGH... WV HAS IT CURRENTLY
TRAVERSING THE INTERMOUNTAIN WEST... AND IT WILL CONTINUE TO
INCREASE IN INTENSITY AS IT ADVANCES EWRD ACROSS THE ROCKIES LATER
THIS EVENING. OVERALL... PRECIP CHANCES ACROSS CENTRAL AND WRN OK
AND WRN N TX REMAIN LOW. THE 00Z ECMWF REMAINS A TAD QUICKER WITH
THE EJECTION OF THE SFC LOW TO THE E/NE THU MORNING... BUT OVERALL
TRACK REMAINS CONSISTENT WHEN COMPARED TO THE SUITE OF GUIDANCE.
BEST CHANCES FOR RAIN WILL BE E/NE OF THE FORECAST AREA ACROSS NERN
OK/SERN KS/SWRN MO... WHERE THE BETTER THETA-E ADVECTION AND
ISENTROPIC RESPONSE WILL RESIDE. ANY CHANCE OF RAIN AND/OR ISOLATED
THUNDER WILL RESIDE EAST OF I-35 TONIGHT THROUGH THURSDAY.
OF GREATER CONCERN WITH THE ARRIVAL OF THIS SFC LOW... STOUT N/NW
WINDS LATE TONIGHT THROUGH THU MORNING. QUITE THE IMPRESSIVE
PRESSURE GRADIENT ASSOCIATED WITH THE COLD FRONT AS IT SWINGS
THROUGH NWRN OK TONIGHT. 3HR PRESSURE CHANGES OF 7 TO 9 MB ARE
EXPECTED... WITH 0-1KM LAPSE RATES OF 6 TO 9 C/KM. BEST CHANCES WILL
BE AFTER MIDNIGHT THROUGH SUNRISE... WITH 40 TO 45 MPH WINDS GUSTING
50 TO 60 MPH. AREA OF GREATEST CONCERN WILL BE ALONG/NORTH OF I-40
AND ALONG/WEST OF I-35. BUFKIT PROFILES WOULD SUGGEST BL WINDS OF 50
TO 60 KTS NEAR/AT SUNRISE FOR NWRN OK. A HIGH WIND WATCH WILL REMAIN
IN EFFECT FOR THE TIME BEING FROM 1 AM TONIGHT THROUGH 1 PM THU. A
PORTION OF THIS WATCH WILL LIKELY BE UPGRADED TO A WARNING AS WE GET
CLOSER TO EVENT TIME. FOREWENT DOING THIS NOW TO AVOID CONFUSION OF
START TIME OF HIGH WINDS. HEAVILY RELATED... FIRE SPREAD POTENTIAL
WILL BE VERY HIGH TO EXTREME FOR MOST OF THE DAY THURS...ESPECIALLY
WEST OF I-35 WHERE RAPID DRYING/MIXING WILL OCCUR DUE TO THE
HIGH WINDS EARLIER IN THE DAY.
BEHIND THE FRONT... TEMPS WILL DIP NEAR NORMAL OVERNIGHT THROUGH
FRIDAY AS WINDS RELAX. TEMPS WILL THEN WARM BACK UP ONCE AGAIN
FRIDAY AS S/SW FLOW RETURNS. AS MENTIONED BY THE DAY SHIFT...SHOULD
START TO SEE A PATTERN CHANGE THROUGH THE WEEKEND AS BROAD TROUGHING
REPLACES THE QUASI-ZONAL FLOW PATTERN AHEAD OF AN APPROACHING
CANADIAN AIRMASS FOR EARLY NEXT WEEK. AT THE MOMENT... A MORE
FEBRUARY FEEL WILL BE IN THE AIR EARLY NEXT WORK WEEK AS A COLD
FRONT SETTLES ACROSS THE CENTRAL PLAINS.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 50 56 32 66 / 10 10 0 0
HOBART OK 46 56 31 64 / 0 0 0 0
WICHITA FALLS TX 55 61 34 68 / 10 0 0 0
GAGE OK 37 52 26 63 / 0 0 0 0
PONCA CITY OK 47 55 28 63 / 50 20 0 0
DURANT OK 59 64 37 66 / 10 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HIGH WIND WATCH FROM LATE TONIGHT THROUGH THURSDAY AFTERNOON FOR
OKZ004>007-009>012-014>018-021>024-033>036.
TX...NONE.
&&
$$
84/23/23
AREA FORECAST DISCUSSION
NWS NORMAN OK
1046 AM CST WED FEB 19 2014
.UPDATE...
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST THROUGH THIS EVENING.
HIGH RESOLUTION MODELS...INCLUDING THE HRRR AND NSSL
WRF...INDICATE THAT CHANCES FOR TSRA WILL REMAIN VERY SLIM OVER
MUCH OF THE REGION. THE ONE EXCEPTION LOOKS TO BE OVER FAR NORTH
CENTRAL/NORTHEAST OKLAHOMA...WHERE ELEVATED THUNDER APPEARS
PROBABLE. THUS...HAVE ADJUSTED POPS TO REFLECT LATER TIMING OF
POSSIBLE SHRA/TSRA AND INCLUDED HIGHER PROBS OVER KAY COUNTY
OKLAHOMA. OTHERWISE...THE FORECAST LOOKS TO BE IN DECENT SHAPE AND
ONLY UPDATED HOURLY TEMPS/DEWPOINTS/WINDS TO REFLECT RECENT OBS.
&&
.PREV DISCUSSION... /ISSUED 605 AM CST WED FEB 19 2014/
AVIATION...19 FEB 12Z TAF ISSUANCE...
EXPECT VFR CIGS TO PREVAIL THROUGH THE MORNING HOURS. DECENT MID-
HIGH DECK OF STRATUS WILL CONTINUE TO STREAM ACROSS THE REGION
TODAY AHEAD OF AN ADVANCING FRONTAL BOUNDARY. EASTERLY WINDS WILL
SLOWLY VEER OUT OF THE S/SE THROUGH THE DAY... WITH INCREASING
MOISTURE IN THE LOWER LEVELS. THIS MAY RESULT IN SOME LIGHT FOG
AND PERHAPS DRIZZLE ACROSS PORTIONS OF CENTRAL AND SRN OK... WITH
MVFR VIS AND CIGS. BIGGEST CONCERN FACING AVIATION THIS TAF PERIOD
ARE THE STRONG N/NW WINDS THAT WILL ARRIVE LATE IN THE PERIOD ACROSS
N/NWRN OK. EXPECT WINDS ANYWHERE FROM 20 TO 30 KTS... WITH GUSTS OF
40 TO 50 EXPECTED NEAR DAY BREAK ACROSS NWRN OK.
JTK
PREV DISCUSSION... /ISSUED 348 AM CST WED FEB 19 2014/
DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED ON THE IMPACTS ASSOCIATED
WITH THE STOUT SFC LOW POISED TO SWING ACROSS THE SRN/CENTRAL PLAINS
TONIGHT/EARLY THU.
CURRENTLY... THE WEAK FRONT FROM TUE EVENING REMAINS STALLED SOUTH
OF THE RED RIVER... DECENT MID 50S TO NEAR 60 DEW POINTS REMAIN
POOLED ALONG THE SFC TROUGH AXIS. WITH CALM WINDS... LIGHT FOG HAS
DEVELOPED AND WILL REMAIN LIKELY THROUGH THE MORNING ALONG THE RED
RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL OK. 09Z SFC ANALYSIS
SHOWS TEMPS HOLDING IN THE UPPER 40S AND 50S ACROSS CENTRAL AND SRN
OK AND WRN N TX WHERE WINDS REMAIN ELEVATED. EXPECT TEMPS TO LOWER A
FEW DEGREES MORE AS WINDS LESSEN SLIGHTLY THROUGH SUNRISE.
AFTER SUNRISE... EXPECT RAPID MOISTURE RETURN TO START THIS MORNING
AS ERLY SFC WINDS VEER TO THE SE THROUGH NOON AHEAD OF THE SFC
LOW/H500 TROUGH. SPEAKING OF THE TROUGH... WV HAS IT CURRENTLY
TRAVERSING THE INTERMOUNTAIN WEST... AND IT WILL CONTINUE TO
INCREASE IN INTENSITY AS IT ADVANCES EWRD ACROSS THE ROCKIES LATER
THIS EVENING. OVERALL... PRECIP CHANCES ACROSS CENTRAL AND WRN OK
AND WRN N TX REMAIN LOW. THE 00Z ECMWF REMAINS A TAD QUICKER WITH
THE EJECTION OF THE SFC LOW TO THE E/NE THU MORNING... BUT OVERALL
TRACK REMAINS CONSISTENT WHEN COMPARED TO THE SUITE OF GUIDANCE.
BEST CHANCES FOR RAIN WILL BE E/NE OF THE FORECAST AREA ACROSS NERN
OK/SERN KS/SWRN MO... WHERE THE BETTER THETA-E ADVECTION AND
ISENTROPIC RESPONSE WILL RESIDE. ANY CHANCE OF RAIN AND/OR ISOLATED
THUNDER WILL RESIDE EAST OF I-35 TONIGHT THROUGH THURSDAY.
OF GREATER CONCERN WITH THE ARRIVAL OF THIS SFC LOW... STOUT N/NW
WINDS LATE TONIGHT THROUGH THU MORNING. QUITE THE IMPRESSIVE
PRESSURE GRADIENT ASSOCIATED WITH THE COLD FRONT AS IT SWINGS
THROUGH NWRN OK TONIGHT. 3HR PRESSURE CHANGES OF 7 TO 9 MB ARE
EXPECTED... WITH 0-1KM LAPSE RATES OF 6 TO 9 C/KM. BEST CHANCES WILL
BE AFTER MIDNIGHT THROUGH SUNRISE... WITH 40 TO 45 MPH WINDS GUSTING
50 TO 60 MPH. AREA OF GREATEST CONCERN WILL BE ALONG/NORTH OF I-40
AND ALONG/WEST OF I-35. BUFKIT PROFILES WOULD SUGGEST BL WINDS OF 50
TO 60 KTS NEAR/AT SUNRISE FOR NWRN OK. A HIGH WIND WATCH WILL REMAIN
IN EFFECT FOR THE TIME BEING FROM 1 AM TONIGHT THROUGH 1 PM THU. A
PORTION OF THIS WATCH WILL LIKELY BE UPGRADED TO A WARNING AS WE GET
CLOSER TO EVENT TIME. FOREWENT DOING THIS NOW TO AVOID CONFUSION OF
START TIME OF HIGH WINDS. HEAVILY RELATED... FIRE SPREAD POTENTIAL
WILL BE VERY HIGH TO EXTREME FOR MOST OF THE DAY THURS...ESPECIALLY
WEST OF I-35 WHERE RAPID DRYING/MIXING WILL OCCUR DUE TO THE
HIGH WINDS EARLIER IN THE DAY.
BEHIND THE FRONT... TEMPS WILL DIP NEAR NORMAL OVERNIGHT THROUGH
FRIDAY AS WINDS RELAX. TEMPS WILL THEN WARM BACK UP ONCE AGAIN
FRIDAY AS S/SW FLOW RETURNS. AS MENTIONED BY THE DAY SHIFT...SHOULD
START TO SEE A PATTERN CHANGE THROUGH THE WEEKEND AS BROAD TROUGHING
REPLACES THE QUASI-ZONAL FLOW PATTERN AHEAD OF AN APPROACHING
CANADIAN AIRMASS FOR EARLY NEXT WEEK. AT THE MOMENT... A MORE
FEBRUARY FEEL WILL BE IN THE AIR EARLY NEXT WORK WEEK AS A COLD
FRONT SETTLES ACROSS THE CENTRAL PLAINS.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 69 50 56 32 / 10 10 10 0
HOBART OK 67 46 56 31 / 0 0 0 0
WICHITA FALLS TX 74 55 61 34 / 0 10 0 0
GAGE OK 64 37 52 26 / 0 0 0 0
PONCA CITY OK 62 47 55 28 / 20 50 20 0
DURANT OK 69 59 64 37 / 20 10 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HIGH WIND WATCH FROM LATE TONIGHT THROUGH THURSDAY AFTERNOON FOR
OKZ004>007-009>012-014>018-021>024-033>036.
TX...NONE.
&&
$$
84/23
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
733 AM EST WED FEB 19 2014
.SYNOPSIS...
A FAST MOVING UPPER LEVEL TROUGH WILL SLIDE ACROSS THE LOWER
GREAT LAKES AND NORTHERN MID-ATLANTIC STATES TODAY...WITH
SECONDARY SURFACE LOW DEVELOPMENT FROM THE SOUTHERN NEW ENGLAND
COAST INTO THE CANADIAN MARITIMES...SIMILAR TO YESTERDAY. A WEAK
AREA OF HIGH PRESSURE WILL MIGRATE OVER THE REGION TONIGHT INTO
EARLY THURSDAY BEHIND THE DEPARTING SYSTEM. A WARM FRONT WILL LIFT
NORTH ACROSS THE AREA THURSDAY NIGHT...BEFORE A STRONG COLD FRONT
SWEEPS THROUGH THE COMMONWEALTH ON FRIDAY. TEMPERATURES SHOULD
AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO WEEKEND BEFORE
TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
**12Z UPDATE** MULTIPLE PTYPE SCENARIO PLAYING OUT WITH
SNOW/SLEET/FZRA MIX IN STATE COLLEGE. RUC 925-850MB WET BULB
TEMPS FAVOR THIS MIX FROM STATE COLLEGE NEWD TO THE LYCOMING
VALLEY AND ENDLESS MTNS. TO THE SOUTH...SLEET COULD MIX IN ALONG
RT 22 INTO THE MID SUSQ VLY. ELSEWHERE EXPECT A QUICK GLAZING OF
ICE. OVERALL...WET BULBS ARE PLAYING IN INTEGRAL ROLE IN
DETERMINING PTYPES...PER EARLIER FCST CONCERNS. MADE SOME MINOR
CHANGES TO ZR ADVY WITH ANOTHER UPDATE LKLY NEEDED SOON GIVEN
SPEED OF PCPN SHIELD.
INCREASING LG SCALE LIFT/500MB HGT FALLS ASSOC WITH APPROACHING
GRT LKS SHORTWAVE MID/UPPER LEVEL TROUGH...AND STG WARM AIR/THETAE
ADVECTION/ISENT LIFT ON NOSE OF 40+KT SWLY LLJ IS RESULTING IN
FAST-MOVG AREA OF PCPN ACRS SE OH/NW WV MOVG INTO SW PA NEAR PIT
AS OF 09Z. SHORT RANGE MESO MODELS BRING THIS PCPN INTO CENTRAL PA
DURING THE PRE-DAWN AND EARLY MORNING HOURS /EXTRAPOLATED TOA IS
APPROX 0930Z IN THE SW ZONES AND AROUND 12Z IN THE ERN
COUNTIES/...OVERSPREADING A COMPLEX LOW-LEVEL THERMAL PROFILE.
LATEST RUC DATA INDICATES 925-850MB TEMPS ARE ABOVE 0C ACRS THE
ENTIRE CWA...BUT THIS CHANGES FOR SOME AREAS AFT FACTORING IN WET
BULB EFFECTS GIVEN DRY AIR IN PLACE WITH RATHER LARGE DEWPT
DEPRESSIONS. TO FURTHER COMPLICATE MATTERS...SFC TEMPS VARY WIDELY
WITH CNTRL-ERN SITES CALM/DECOUPLED AND WRN SITES WEAKLY MIXED AOA
32F. TO GET A SENSE OF THIS GRADIENT...THE 08Z THE TEMP DIFF FROM
MGW TO SEG WAS 34 DEGREES...48F VS. 14F. THE LOCAL TEMP HERE AT
THE OFFICE IS AROUND 19-20F.
MADE NO CHANGES TO ZR ADVY HEADLINE COVERING NEARLY ALL OF THE
CWA. HOWEVER CONCERN IS FOR MULTIPLE PTYPE SCENARIO GIVEN
COMPLEXITY OF BLYR THERMAL STRUCTURE+WET BULB EFFECTS...WITH THE
GREATEST POTNL FOR AN INITIAL PERIOD OF SNOW (MOST LKLY SLEET)
ACRS NERN 1/2 OF THE CWA...ESPECIALLY THE ENDLESS MTN/SRN POCONO
REGION NE OF THE LYCOMING VALLEY/IPT. ANTICIPATE UPDATING THE WX
GRIDS ONCE THE PCPN TYPES START TO SHOW THEIR HAND OVER THE NEXT
1-3 HRS.
TEMPS SHOULD WARM ABOVE FZG BY MIDDAY THUS ENDING THE THREAT FOR
ZR. WILL NEED TO SEE IF MDLS ARE TOO AGGRESSIVE IN WARMING TEMPS
GIVEN THE INITIAL WET BULBING AT THE ONSET OF PCPN. TEMPS SHOULD
START TO WARM ONCE WINDS SHIFT TO THE WEST BEHIND OCCLD FRNT. ONCL
LGT RAIN WILL CONTINUE INTO THE EARLY AFTN WITH THE HIGHEST POPS
OVER THE ERN ZONES BASED ON A CONSENSUS BLEND OF MDL QPFS...AND
NEAR SECONDARY SFC LOW DEVELOPING INVOF THE NJ COAST. A RAIN/SNOW
MIX IS POSSIBLE OVER THE NW MTNS AS COLDER AIR ALOFT ARRIVES ON
THE BACKSIDE OF THE SHORTWAVE TROUGH.
PCPN ENDS FROM SW TO NE BY THIS EVE AS HIGH PRES MIGRATES EWD FROM
THE UPPER OH VLY INTO PA...PROVIDING DRY WX FOR THE OVERNIGHT PD.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
A STRONG MID-LVL TROUGH CROSSING THE PLAINS STATES THURS IS FCST
TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS AND
MS/OH VLYS THURS NGT. AT THE SFC...HIGH PRES WILL SHIFT OFF THE
MID-ATL COAST EARLY THURS AS A WARM FRONT...EXTENDING EWD FROM
DEEPENING SFC LOW MOVG NNEWD FROM SERN KN TO LK SUPERIOR BY THE
END OF THE PD...LIFTS NWD ACRS THE AREA BY 00Z FRI. THE MAIN
SYNOPTIC FEATURE OF INTEREST WILL BE THE SHARP/TRAILING COLD FRONT
WHICH WILL BE CROSSING THE APPLCHNS AROUND 12Z FRI. THIS FRONT IS
EXPECTED TO BE A FOCUS FOR A LINE OF LOW-TOPPED CONVECTION WHICH
COULD REACH THE WRN ALLEGHENIES EARLY FRI MORNING.
QUESTION FOR THURS WILL BE THE EXTENT OF THE LLVL CAD PATTERN
GIVEN THE EXPECTED ONSLAUGHT OF LLVL WAA IN ADVANCE OF DYNAMIC
MIDWEST SYSTEM. THE HIRES NAM SHOWS NELY AGEO WINDS HOLDING SFC
TEMPS IN THE 35-40F RANGE WITH SOME OVERRUNNING PCPN SPREADING
INTO NWRN SECTIONS. SREF DATA SHOWS THE DOMINANT PTYPES AS RAIN
WITH VERY LOW PROBS FOR FROZEN/FZG PCPN IN THE N-CNTRL MTNS/N OF
I-80. IN GENERAL..STAYED VERY CLOSE TO CONSENSUS BLEND FOR MOST
ELEMENTS...WHICH FAVORED DAYTIME TEMPS AROUND 40F AND CATEGORICAL
POPS ACRS THE FAR NW ZONES THURS NGT. SPC DAY 2+3 OUTLOOKS PLACES
THE AREA IN GENERAL RISK HOWEVER MAY NEED TO ADD ENHANCED WORDING
IN HWO DUE TO POSSIBLE NCFRB/LOW TOPPED SQ LINE RACING ACRS THE
AREA DURING THE PRE-DAWN AND MORNING HOURS FRI. THE SYSTEM IS
PROGRESSIVE WHICH WILL LIMIT HVY RAIN POTNL/FLOOD THREAT...HOWEVER
ICE JAM EFFECTS COULD BE A CONCERN. ATTM DO NOT ANTICIPATE RAPID
SNOWMELT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS COLD FRONT SLIDES ACROSS ON FRI...PRECIP WILL PUSH EASTWARD
AND COOLER AIR WILL FILTER BACK INTO THE REGION. GFS/ECMWF NOW IN
QUITE GOOD ALIGNMENT WITH MAIN FEATURES AS THIS SYSTEM
EVOLVES...WITH PRECIP ENDING BY LUNCHTIME FRI.
BROAD TROUGH DEVELOPS ACROSS EASTERN 2/3RDS OF U.S. FOR THE
WEEKEND...GIVING US A SLOW AND STEADY RETURN BACK TO SLIGHTLY
BELOW NORMAL TEMPERATURES. WEAK FRONT PUSHES THROUGH MID-WEEKEND
THAT MAY BRING LIGHT ACCUMS OF SNOW. OTHERWISE...NO BIG SYSTEMS ON
THE HORIZON. SNOWFLAKES WILL LINGER OVER THE WESTERN/NORTHERN
HIGHER TERRAIN IN PERSISTENT NW/W FLOW.
AS FAR AS THE SNOW COVER AND RIVER ICE...WARMING TREND LATE THIS
WEEK WILL BE FAIRLY SHORT-LIVED...SO MELTING OF SNOW AND ICE WILL
REMAIN GRADUAL...WHICH SHOULD KEEP POTENTIAL FOR WIDESPREAD
PROBLEMS LOW.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
BANDS OF MIXED PRECIPITATION CONTINUE TO MOVE ACROSS CENTRAL PA
THIS MORNING. THE INITIAL EDGE IS SNOW...BUT QUICKLY TRANSITIONING
TO A SLEET...FREEZING RAIN MIX AND THEN INTO FREEZING RAIN. THIS
BAND WILL BE HEAVY AT TIMES...AND MOVING SOUTHWEST TO NORTHEAST.
MVFR TO IFR CONDITIONS WILL BE POSSIBLE AT ALL TAF SITES THROUGH
18Z. THE CENTRAL AND WESTERN TAF SITES WILL IMPROVE LATE MORNING
TO EARLY AFTERNOON. LNS AND MDT WILL HAVE MVFR LINGER INTO MID
AFTERNOON. THIS WILL BE FOLLOWED BY A COOLER AND DRIER NW FLOW IN
THE WAKE OF THE FRONT. THERE COULD BE SOME LINGERING MVFR/IFR IN
SCATTERED RAIN OR SNOW SHOWERS...BUT THESE WILL BE VERY BRIEF AND
CONFINED TO THE WESTERN MOUNTAINS.
LLWS WILL BE ASSOCIATED WITH THIS LINE...WITH WIND SHEAR OF UP TO
50KTS POSSIBLE AT 020KFT AT JST...UNV...IPT AND AOO THROUGH 16Z.
OUTLOOK...
THU...MVFR/IFR LIKELY WITH SHOWERS AND FOG.
FRI...SHRA/REDUCED CIGS LIKELY.
SAT...NO SIG WX EXPECTED.
SUN...MVFR/SCT SHSN NW. MAINLY VFR ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR PAZ006-012-018-
019-025>028-037-041-042-045-046-049>053-056>059.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ005-
010-011-017-024-033.
FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
PAZ034>036-063>066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
702 AM EST WED FEB 19 2014
.SYNOPSIS...
A FAST MOVING UPPER LEVEL TROUGH WILL SLIDE ACROSS THE LOWER
GREAT LAKES AND NORTHERN MID-ATLANTIC STATES TODAY...WITH
SECONDARY SURFACE LOW DEVELOPMENT FROM THE SOUTHERN NEW ENGLAND
COAST INTO THE CANADIAN MARITIMES...SIMILAR TO YESTERDAY. A WEAK
AREA OF HIGH PRESSURE WILL MIGRATE OVER THE REGION TONIGHT INTO
EARLY THURSDAY BEHIND THE DEPARTING SYSTEM. A WARM FRONT WILL LIFT
NORTH ACROSS THE AREA THURSDAY NIGHT...BEFORE A STRONG COLD FRONT
SWEEPS THROUGH THE COMMONWEALTH ON FRIDAY. TEMPERATURES SHOULD
AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO WEEKEND BEFORE
TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
**12Z UPDATE** MULTIPLE PTYPE SCENARIO PLAYING OUT WITH
SNOW/SLEET/FZRA MIX IN STATE COLLEGE. RUC 925-850MB WET BULB
TEMPS FAVOR THIS MIX FROM STATE COLLEGE NEWD TO THE LYCOMING
VALLEY AND ENDLESS MTNS. TO THE SOUTH...SLEET COULD MIX IN ALONG
RT 22 INTO THE MID SUSQ VLY. ELSEWHERE EXPECT A QUICK GLAZING OF
ICE. OVERALL...WET BULBS ARE PLAYING IN INTEGRAL ROLE IN
DETERMINING PTYPES...PER EARLIER FCST CONCERNS. MADE SOME MINOR
CHANGES TO ZR ADVY WITH ANOTHER UPDATE LKLY NEEDED SOON GIVEN
SPEED OF PCPN SHIELD.
INCREASING LG SCALE LIFT/500MB HGT FALLS ASSOC WITH APPROACHING
GRT LKS SHORTWAVE MID/UPPER LEVEL TROUGH...AND STG WARM AIR/THETAE
ADVECTION/ISENT LIFT ON NOSE OF 40+KT SWLY LLJ IS RESULTING IN
FAST-MOVG AREA OF PCPN ACRS SE OH/NW WV MOVG INTO SW PA NEAR PIT
AS OF 09Z. SHORT RANGE MESO MODELS BRING THIS PCPN INTO CENTRAL PA
DURING THE PRE-DAWN AND EARLY MORNING HOURS /EXTRAPOLATED TOA IS
APPROX 0930Z IN THE SW ZONES AND AROUND 12Z IN THE ERN
COUNTIES/...OVERSPREADING A COMPLEX LOW-LEVEL THERMAL PROFILE.
LATEST RUC DATA INDICATES 925-850MB TEMPS ARE ABOVE 0C ACRS THE
ENTIRE CWA...BUT THIS CHANGES FOR SOME AREAS AFT FACTORING IN WET
BULB EFFECTS GIVEN DRY AIR IN PLACE WITH RATHER LARGE DEWPT
DEPRESSIONS. TO FURTHER COMPLICATE MATTERS...SFC TEMPS VARY WIDELY
WITH CNTRL-ERN SITES CALM/DECOUPLED AND WRN SITES WEAKLY MIXED AOA
32F. TO GET A SENSE OF THIS GRADIENT...THE 08Z THE TEMP DIFF FROM
MGW TO SEG WAS 34 DEGREES...48F VS. 14F. THE LOCAL TEMP HERE AT
THE OFFICE IS AROUND 19-20F.
MADE NO CHANGES TO ZR ADVY HEADLINE COVERING NEARLY ALL OF THE
CWA. HOWEVER CONCERN IS FOR MULTIPLE PTYPE SCENARIO GIVEN
COMPLEXITY OF BLYR THERMAL STRUCTURE+WET BULB EFFECTS...WITH THE
GREATEST POTNL FOR AN INITIAL PERIOD OF SNOW (MOST LKLY SLEET)
ACRS NERN 1/2 OF THE CWA...ESPECIALLY THE ENDLESS MTN/SRN POCONO
REGION NE OF THE LYCOMING VALLEY/IPT. ANTICIPATE UPDATING THE WX
GRIDS ONCE THE PCPN TYPES START TO SHOW THEIR HAND OVER THE NEXT
1-3 HRS.
TEMPS SHOULD WARM ABOVE FZG BY MIDDAY THUS ENDING THE THREAT FOR
ZR. WILL NEED TO SEE IF MDLS ARE TOO AGGRESSIVE IN WARMING TEMPS
GIVEN THE INITIAL WET BULBING AT THE ONSET OF PCPN. TEMPS SHOULD
START TO WARM ONCE WINDS SHIFT TO THE WEST BEHIND OCCLD FRNT. ONCL
LGT RAIN WILL CONTINUE INTO THE EARLY AFTN WITH THE HIGHEST POPS
OVER THE ERN ZONES BASED ON A CONSENSUS BLEND OF MDL QPFS...AND
NEAR SECONDARY SFC LOW DEVELOPING INVOF THE NJ COAST. A RAIN/SNOW
MIX IS POSSIBLE OVER THE NW MTNS AS COLDER AIR ALOFT ARRIVES ON
THE BACKSIDE OF THE SHORTWAVE TROUGH.
PCPN ENDS FROM SW TO NE BY THIS EVE AS HIGH PRES MIGRATES EWD FROM
THE UPPER OH VLY INTO PA...PROVIDING DRY WX FOR THE OVERNIGHT PD.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
A STRONG MID-LVL TROUGH CROSSING THE PLAINS STATES THURS IS FCST
TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS AND
MS/OH VLYS THURS NGT. AT THE SFC...HIGH PRES WILL SHIFT OFF THE
MID-ATL COAST EARLY THURS AS A WARM FRONT...EXTENDING EWD FROM
DEEPENING SFC LOW MOVG NNEWD FROM SERN KN TO LK SUPERIOR BY THE
END OF THE PD...LIFTS NWD ACRS THE AREA BY 00Z FRI. THE MAIN
SYNOPTIC FEATURE OF INTEREST WILL BE THE SHARP/TRAILING COLD FRONT
WHICH WILL BE CROSSING THE APPLCHNS AROUND 12Z FRI. THIS FRONT IS
EXPECTED TO BE A FOCUS FOR A LINE OF LOW-TOPPED CONVECTION WHICH
COULD REACH THE WRN ALLEGHENIES EARLY FRI MORNING.
QUESTION FOR THURS WILL BE THE EXTENT OF THE LLVL CAD PATTERN
GIVEN THE EXPECTED ONSLAUGHT OF LLVL WAA IN ADVANCE OF DYNAMIC
MIDWEST SYSTEM. THE HIRES NAM SHOWS NELY AGEO WINDS HOLDING SFC
TEMPS IN THE 35-40F RANGE WITH SOME OVERRUNNING PCPN SPREADING
INTO NWRN SECTIONS. SREF DATA SHOWS THE DOMINANT PTYPES AS RAIN
WITH VERY LOW PROBS FOR FROZEN/FZG PCPN IN THE N-CNTRL MTNS/N OF
I-80. IN GENERAL..STAYED VERY CLOSE TO CONSENSUS BLEND FOR MOST
ELEMENTS...WHICH FAVORED DAYTIME TEMPS AROUND 40F AND CATEGORICAL
POPS ACRS THE FAR NW ZONES THURS NGT. SPC DAY 2+3 OUTLOOKS PLACES
THE AREA IN GENERAL RISK HOWEVER MAY NEED TO ADD ENHANCED WORDING
IN HWO DUE TO POSSIBLE NCFRB/LOW TOPPED SQ LINE RACING ACRS THE
AREA DURING THE PRE-DAWN AND MORNING HOURS FRI. THE SYSTEM IS
PROGRESSIVE WHICH WILL LIMIT HVY RAIN POTNL/FLOOD THREAT...HOWEVER
ICE JAM EFFECTS COULD BE A CONCERN. ATTM DO NOT ANTICIPATE RAPID
SNOWMELT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS COLD FRONT SLIDES ACROSS ON FRI...PRECIP WILL PUSH EASTWARD
AND COOLER AIR WILL FILTER BACK INTO THE REGION. GFS/ECMWF NOW IN
QUITE GOOD ALIGNMENT WITH MAIN FEATURES AS THIS SYSTEM
EVOLVES...WITH PRECIP ENDING BY LUNCHTIME FRI.
BROAD TROUGH DEVELOPS ACROSS EASTERN 2/3RDS OF U.S. FOR THE
WEEKEND...GIVING US A SLOW AND STEADY RETURN BACK TO SLIGHTLY
BELOW NORMAL TEMPERATURES. WEAK FRONT PUSHES THROUGH MID-WEEKEND
THAT MAY BRING LIGHT ACCUMS OF SNOW. OTHERWISE...NO BIG SYSTEMS ON
THE HORIZON. SNOWFLAKES WILL LINGER OVER THE WESTERN/NORTHERN
HIGHER TERRAIN IN PERSISTENT NW/W FLOW.
AS FAR AS THE SNOW COVER AND RIVER ICE...WARMING TREND LATE THIS
WEEK WILL BE FAIRLY SHORT-LIVED...SO MELTING OF SNOW AND ICE WILL
REMAIN GRADUAL...WHICH SHOULD KEEP POTENTIAL FOR WIDESPREAD
PROBLEMS LOW.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRESSURE...CLEAR SKIES...LIGHT WINDS AND SNOWPACK HAVE ALLOWED
FOR FOG/MIST ACROSS SOUTHEASTERN AND CENTRAL PA OVERNIGHT. THE
THICKEST FOG WAS AT LNS...AND THAT HAS SINCE LIFTED. THERE IS A
CHANCE FOR FOG AT LNS BETWEEN 11Z-15Z...OUT AHEAD OF THE NEXT BAND
OF PRECIPITATION. EXPECT FOG/MIST AT UNV...MDT AND LNS AND SHOULD
CONTINUE THROUGH MID MORNING.
PRECIP ASSOCIATED WITH THE APPROACHING COLD FRONT WILL BEGIN
MOVING INTO SOUTHWESTERN AREAS AROUND OR JUST BEFORE
DAWN...PROBABLY IN THE FORM OF FREEZING RAIN/DRIZZLE OR A LIGHT
WINTRY MIX. MOST TERMINALS WILL LIKELY EXPERIENCE A LIGHT ICING
ISSUE FOR A FEW HOURS AS THE PRECIP MOVES INTO THE REGION. THE
THREAT FOR ICING SHOULD DIMINISH BY MID TO LATE MORNING AS
TEMPERATURES RECOVER SLOWLY ABOVE FREEZING. MVFR/IFR CAN BE
EXPECTED WITH THE COMBINATION OF THE MILDER AIR AND LIGHT PRECIP
MOVING IN OVER OUR DEEP SNOW PACK.
THE COLD FRONT SHOULD MOVE THROUGH THE AREA BY EARLY TO MID
AFTERNOON...FOLLOWED BY A COOLER AND DRIER NW FLOW IN THE WAKE OF
THE FRONT. THERE COULD BE SOME LINGERING MVFR/IFR IN SCATTERED
RAIN OR SNOW SHOWERS...BUT THESE WILL BE VERY BRIEF AND CONFINED
TO THE WESTERN MOUNTAINS.
OUTLOOK...
THU...MVFR/IFR LIKELY WITH SHOWERS AND FOG.
FRI...SHRA/REDUCED CIGS LIKELY.
SAT...NO SIG WX EXPECTED.
SUN...MVFR/SCT SHSN NW. MAINLY VFR ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR PAZ006-012-018-
019-025>028-037-041-042-045-046-049>053-056>059.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ005-
010-011-017-024-033.
FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
PAZ034>036-063>066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
443 AM EST WED FEB 19 2014
.SYNOPSIS...
A FAST MOVING UPPER LEVEL TROUGH WILL SLIDE ACROSS THE LOWER
GREAT LAKES AND NORTHERN MID-ATLANTIC STATES TODAY...WITH
SECONDARY SURFACE LOW DEVELOPMENT FROM THE SOUTHERN NEW ENGLAND
COAST INTO THE CANADIAN MARITIMES...SIMILAR TO YESTERDAY. A WEAK
AREA OF HIGH PRESSURE WILL MIGRATE OVER THE REGION TONIGHT INTO
EARLY THURSDAY BEHIND THE DEPARTING SYSTEM. A WARM FRONT WILL LIFT
NORTH ACROSS THE AREA THURSDAY NIGHT...BEFORE A STRONG COLD FRONT
SWEEPS THROUGH THE COMMONWEALTH ON FRIDAY. TEMPERATURES SHOULD
AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO WEEKEND BEFORE
TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
**UPDATE** EXPANDED ZR ADVY FOR REST OF CWA /LAURELS AND
WARREN COUNTY/. OBSERVATIONS FROM PBZ AREA INDICATE THAT DESPITE
TEMPS AOA 32F...RAIN IS FREEZING ON CONTACT DUE TO COLD GROUND
TEMPS.
INCREASING LG SCALE LIFT/500MB HGT FALLS ASSOC WITH APPROACHING
GRT LKS SHORTWAVE MID/UPPER LEVEL TROUGH...AND STG WARM AIR/THETAE
ADVECTION/ISENT LIFT ON NOSE OF 40+KT SWLY LLJ IS RESULTING IN
FAST-MOVG AREA OF PCPN ACRS SE OH/NW WV MOVG INTO SW PA NEAR PIT
AS OF 09Z. SHORT RANGE MESO MODELS BRING THIS PCPN INTO CENTRAL PA
DURING THE PRE-DAWN AND EARLY MORNING HOURS /EXTRAPOLATED TOA IS
APPROX 0930Z IN THE SW ZONES AND AROUND 12Z IN THE ERN
COUNTIES/...OVERSPREADING A COMPLEX LOW-LEVEL THERMAL PROFILE.
LATEST RUC DATA INDICATES 925-850MB TEMPS ARE ABOVE 0C ACRS THE
ENTIRE CWA...BUT THIS CHANGES FOR SOME AREAS AFT FACTORING IN WET
BULB EFFECTS GIVEN DRY AIR IN PLACE WITH RATHER LARGE DEWPT
DEPRESSIONS. TO FURTHER COMPLICATE MATTERS...SFC TEMPS VARY WIDELY
WITH CNTRL-ERN SITES CALM/DECOUPLED AND WRN SITES WEAKLY MIXED AOA
32F. TO GET A SENSE OF THIS GRADIENT...THE 08Z THE TEMP DIFF FROM
MGW TO SEG WAS 34 DEGREES...48F VS. 14F. THE LOCAL TEMP HERE AT
THE OFFICE IS AROUND 19-20F.
MADE NO CHANGES TO ZR ADVY HEADLINE COVERING NEARLY ALL OF THE
CWA. HOWEVER CONCERN IS FOR MULTIPLE PTYPE SCENARIO GIVEN
COMPLEXITY OF BLYR THERMAL STRUCTURE+WET BULB EFFECTS...WITH THE
GREATEST POTNL FOR AN INITIAL PERIOD OF SNOW (MOST LKLY SLEET)
ACRS NERN 1/2 OF THE CWA...ESPECIALLY THE ENDLESS MTN/SRN POCONO
REGION NE OF THE LYCOMING VALLEY/IPT. ANTICIPATE UPDATING THE WX
GRIDS ONCE THE PCPN TYPES START TO SHOW THEIR HAND OVER THE NEXT
1-3 HRS.
TEMPS SHOULD WARM ABOVE FZG BY MIDDAY THUS ENDING THE THREAT FOR
ZR. WILL NEED TO SEE IF MDLS ARE TOO AGGRESSIVE IN WARMING TEMPS
GIVEN THE INITIAL WET BULBING AT THE ONSET OF PCPN. TEMPS SHOULD
START TO WARM ONCE WINDS SHIFT TO THE WEST BEHIND OCCLD FRNT. ONCL
LGT RAIN WILL CONTINUE INTO THE EARLY AFTN WITH THE HIGHEST POPS
OVER THE ERN ZONES BASED ON A CONSENSUS BLEND OF MDL QPFS...AND
NEAR SECONDARY SFC LOW DEVELOPING INVOF THE NJ COAST. A RAIN/SNOW
MIX IS POSSIBLE OVER THE NW MTNS AS COLDER AIR ALOFT ARRIVES ON
THE BACKSIDE OF THE SHORTWAVE TROUGH.
PCPN ENDS FROM SW TO NE BY THIS EVE AS HIGH PRES MIGRATES EWD FROM
THE UPPER OH VLY INTO PA...PROVIDING DRY WX FOR THE OVERNIGHT PD.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
A STRONG MID-LVL TROUGH CROSSING THE PLAINS STATES THURS IS FCST
TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS AND
MS/OH VLYS THURS NGT. AT THE SFC...HIGH PRES WILL SHIFT OFF THE
MID-ATL COAST EARLY THURS AS A WARM FRONT...EXTENDING EWD FROM
DEEPENING SFC LOW MOVG NNEWD FROM SERN KN TO LK SUPERIOR BY THE
END OF THE PD...LIFTS NWD ACRS THE AREA BY 00Z FRI. THE MAIN
SYNOPTIC FEATURE OF INTEREST WILL BE THE SHARP/TRAILING COLD FRONT
WHICH WILL BE CROSSING THE APPLCHNS AROUND 12Z FRI. THIS FRONT IS
EXPECTED TO BE A FOCUS FOR A LINE OF LOW-TOPPED CONVECTION WHICH
COULD REACH THE WRN ALLEGHENIES EARLY FRI MORNING.
QUESTION FOR THURS WILL BE THE EXTENT OF THE LLVL CAD PATTERN
GIVEN THE EXPECTED ONSLAUGHT OF LLVL WAA IN ADVANCE OF DYNAMIC
MIDWEST SYSTEM. THE HIRES NAM SHOWS NELY AGEO WINDS HOLDING SFC
TEMPS IN THE 35-40F RANGE WITH SOME OVERRUNNING PCPN SPREADING
INTO NWRN SECTIONS. SREF DATA SHOWS THE DOMINANT PTYPES AS RAIN
WITH VERY LOW PROBS FOR FROZEN/FZG PCPN IN THE N-CNTRL MTNS/N OF
I-80. IN GENERAL..STAYED VERY CLOSE TO CONSENSUS BLEND FOR MOST
ELEMENTS...WHICH FAVORED DAYTIME TEMPS AROUND 40F AND CATEGORICAL
POPS ACRS THE FAR NW ZONES THURS NGT. SPC DAY 2+3 OUTLOOKS PLACES
THE AREA IN GENERAL RISK HOWEVER MAY NEED TO ADD ENHANCED WORDING
IN HWO DUE TO POSSIBLE NCFRB/LOW TOPPED SQ LINE RACING ACRS THE
AREA DURING THE PRE-DAWN AND MORNING HOURS FRI. THE SYSTEM IS
PROGRESSIVE WHICH WILL LIMIT HVY RAIN POTNL/FLOOD THREAT...HOWEVER
ICE JAM EFFECTS COULD BE A CONCERN. ATTM DO NOT ANTICIPATE RAPID
SNOWMELT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS COLD FRONT SLIDES ACROSS ON FRI...PRECIP WILL PUSH EASTWARD
AND COOLER AIR WILL FILTER BACK INTO THE REGION. GFS/ECMWF NOW IN
QUITE GOOD ALIGNMENT WITH MAIN FEATURES AS THIS SYSTEM
EVOLVES...WITH PRECIP ENDING BY LUNCHTIME FRI.
BROAD TROUGH DEVELOPS ACROSS EASTERN 2/3RDS OF U.S. FOR THE
WEEKEND...GIVING US A SLOW AND STEADY RETURN BACK TO SLIGHTLY
BELOW NORMAL TEMPERATURES. WEAK FRONT PUSHES THROUGH MID-WEEKEND
THAT MAY BRING LIGHT ACCUMS OF SNOW. OTHERWISE...NO BIG SYSTEMS ON
THE HORIZON. SNOWFLAKES WILL LINGER OVER THE WESTERN/NORTHERN
HIGHER TERRAIN IN PERSISTENT NW/W FLOW.
AS FAR AS THE SNOW COVER AND RIVER ICE...WARMING TREND LATE THIS
WEEK WILL BE FAIRLY SHORT-LIVED...SO MELTING OF SNOW AND ICE WILL
REMAIN GRADUAL...WHICH SHOULD KEEP POTENTIAL FOR WIDESPREAD
PROBLEMS LOW.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRESSURE...CLEAR SKIES...LIGHT WINDS AND SNOWPACK HAVE ALLOWED
FOR FOG/MIST ACROSS SOUTHEASTERN AND CENTRAL PA OVERNIGHT. THE
THICKEST FOG WAS AT LNS...AND THAT HAS SINCE LIFTED. THERE IS A
CHANCE FOR FOG AT LNS BETWEEN 11Z-15Z...OUT AHEAD OF THE NEXT BAND
OF PRECIPITATION. EXPECT FOG/MIST AT UNV...MDT AND LNS AND SHOULD
CONTINUE THROUGH MID MORNING.
PRECIP ASSOCIATED WITH THE APPROACHING COLD FRONT WILL BEGIN
MOVING INTO SOUTHWESTERN AREAS AROUND OR JUST BEFORE
DAWN...PROBABLY IN THE FORM OF FREEZING RAIN/DRIZZLE OR A LIGHT
WINTRY MIX. MOST TERMINALS WILL LIKELY EXPERIENCE A LIGHT ICING
ISSUE FOR A FEW HOURS AS THE PRECIP MOVES INTO THE REGION. THE
THREAT FOR ICING SHOULD DIMINISH BY MID TO LATE MORNING AS
TEMPERATURES RECOVER SLOWLY ABOVE FREEZING. MVFR/IFR CAN BE
EXPECTED WITH THE COMBINATION OF THE MILDER AIR AND LIGHT PRECIP
MOVING IN OVER OUR DEEP SNOW PACK.
THE COLD FRONT SHOULD MOVE THROUGH THE AREA BY EARLY TO MID
AFTERNOON...FOLLOWED BY A COOLER AND DRIER NW FLOW IN THE WAKE OF
THE FRONT. THERE COULD BE SOME LINGERING MVFR/IFR IN SCATTERED
RAIN OR SNOW SHOWERS...BUT THESE WILL BE VERY BRIEF AND CONFINED
TO THE WESTERN MOUNTAINS.
OUTLOOK...
THU...MVFR/IFR LIKELY WITH SHOWERS AND FOG.
FRI...SHRA/REDUCED CIGS LIKELY.
SAT...NO SIG WX EXPECTED.
SUN...MVFR/SCT SHSN NW. MAINLY VFR ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR PAZ006-012-037-
041-042-045-046-049>053-057>059.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ004-
005-010-011-017>019-024>028-033>036-056-063>066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
412 AM EST WED FEB 19 2014
.SYNOPSIS...
A FAST MOVING UPPER LEVEL TROUGH WILL SLIDE ACROSS THE LOWER
GREAT LAKES AND NORTHERN MID-ATLANTIC STATES TODAY...WITH
SECONDARY SURFACE LOW DEVELOPMENT FROM THE SOUTHERN NEW ENGLAND
COAST INTO THE CANADIAN MARITIMES...SIMILAR TO YESTERDAY. A WEAK
AREA OF HIGH PRESSURE WILL MIGRATE OVER THE REGION TONIGHT INTO
EARLY THURSDAY BEHIND THE DEPARTING SYSTEM. A WARM FRONT WILL LIFT
NORTH ACROSS THE AREA THURSDAY NIGHT...BEFORE A STRONG COLD FRONT
SWEEPS THROUGH THE COMMONWEALTH ON FRIDAY. TEMPERATURES SHOULD
AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO WEEKEND BEFORE
TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
INCREASING LG SCALE LIFT/500MB HGT FALLS ASSOC WITH APPROACHING
GRT LKS SHORTWAVE MID/UPPER LEVEL TROUGH...AND STG WARM AIR/THETAE
ADVECTION/ISENT LIFT ON NOSE OF 40+KT SWLY LLJ IS RESULTING IN
FAST-MOVG AREA OF PCPN ACRS SE OH/NW WV MOVG INTO SW PA NEAR PIT
AS OF 09Z. SHORT RANGE MESO MODELS BRING THIS PCPN INTO CENTRAL PA
DURING THE PRE-DAWN AND EARLY MORNING HOURS /EXTRAPOLATED TOA IS
APPROX 0930Z IN THE SW ZONES AND AROUND 12Z IN THE ERN
COUNTIES/...OVERSPREADING A COMPLEX LOW-LEVEL THERMAL PROFILE.
LATEST RUC DATA INDICATES 925-850MB TEMPS ARE ABOVE 0C ACRS THE
ENTIRE CWA...BUT THIS CHANGES FOR SOME AREAS AFT FACTORING IN WET
BULB EFFECTS GIVEN DRY AIR IN PLACE WITH RATHER LARGE DEWPT
DEPRESSIONS. TO FURTHER COMPLICATE MATTERS...SFC TEMPS VARY WIDELY
WITH CNTRL-ERN SITES CALM/DECOUPLED AND WRN SITES WEAKLY MIXED AOA
32F. TO GET A SENSE OF THIS GRADIENT...THE 08Z THE TEMP DIFF FROM
MGW TO SEG WAS 34 DEGREES...48F VS. 14F. THE LOCAL TEMP HERE AT
THE OFFICE IS AROUND 19-20F.
MADE NO CHANGES TO ZR ADVY HEADLINE COVERING NEARLY ALL OF THE
CWA. HOWEVER CONCERN IS FOR MULTIPLE PTYPE SCENARIO GIVEN
COMPLEXITY OF BLYR THERMAL STRUCTURE+WET BULB EFFECTS...WITH THE
GREATEST POTNL FOR AN INITIAL PERIOD OF SNOW (MOST LKLY SLEET)
ACRS NERN 1/2 OF THE CWA...ESPECIALLY THE ENDLESS MTN/SRN POCONO
REGION NE OF THE LYCOMING VALLEY/IPT. ANTICIPATE UPDATING THE WX
GRIDS ONCE THE PCPN TYPES START TO SHOW THEIR HAND OVER THE NEXT
1-3 HRS.
TEMPS SHOULD WARM ABOVE FZG BY MIDDAY THUS ENDING THE THREAT FOR
ZR. WILL NEED TO SEE IF MDLS ARE TOO AGGRESSIVE IN WARMING TEMPS
GIVEN THE INITIAL WET BULBING AT THE ONSET OF PCPN. TEMPS SHOULD
START TO WARM ONCE WINDS SHIFT TO THE WEST BEHIND OCCLD FRNT. ONCL
LGT RAIN WILL CONTINUE INTO THE EARLY AFTN WITH THE HIGHEST POPS
OVER THE ERN ZONES BASED ON A CONSENSUS BLEND OF MDL QPFS...AND
NEAR SECONDARY SFC LOW DEVELOPING INVOF THE NJ COAST. A RAIN/SNOW
MIX IS POSSIBLE OVER THE NW MTNS AS COLDER AIR ALOFT ARRIVES ON
THE BACKSIDE OF THE SHORTWAVE TROUGH.
PCPN ENDS FROM SW TO NE BY THIS EVE AS HIGH PRES MIGRATES EWD FROM
THE UPPER OH VLY INTO PA...PROVIDING DRY WX FOR THE OVERNIGHT PD.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
A STRONG MID-LVL TROUGH CROSSING THE PLAINS STATES THURS IS FCST
TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS AND
MS/OH VLYS THURS NGT. AT THE SFC...HIGH PRES WILL SHIFT OFF THE
MID-ATL COAST EARLY THURS AS A WARM FRONT...EXTENDING EWD FROM
DEEPENING SFC LOW MOVG NNEWD FROM SERN KN TO LK SUPERIOR BY THE
END OF THE PD...LIFTS NWD ACRS THE AREA BY 00Z FRI. THE MAIN
SYNOPTIC FEATURE OF INTEREST WILL BE THE SHARP/TRAILING COLD FRONT
WHICH WILL BE CROSSING THE APPLCHNS AROUND 12Z FRI. THIS FRONT IS
EXPECTED TO BE A FOCUS FOR A LINE OF LOW-TOPPED CONVECTION WHICH
COULD REACH THE WRN ALLEGHENIES EARLY FRI MORNING.
QUESTION FOR THURS WILL BE THE EXTENT OF THE LLVL CAD PATTERN
GIVEN THE EXPECTED ONSLAUGHT OF LLVL WAA IN ADVANCE OF DYNAMIC
MIDWEST SYSTEM. THE HIRES NAM SHOWS NELY AGEO WINDS HOLDING SFC
TEMPS IN THE 35-40F RANGE WITH SOME OVERRUNNING PCPN SPREADING
INTO NWRN SECTIONS. SREF DATA SHOWS THE DOMINANT PTYPES AS RAIN
WITH VERY LOW PROBS FOR FROZEN/FZG PCPN IN THE N-CNTRL MTNS/N OF
I-80. IN GENERAL..STAYED VERY CLOSE TO CONSENSUS BLEND FOR MOST
ELEMENTS...WHICH FAVORED DAYTIME TEMPS AROUND 40F AND CATEGORICAL
POPS ACRS THE FAR NW ZONES THURS NGT. SPC DAY 2+3 OUTLOOKS PLACES
THE AREA IN GENERAL RISK HOWEVER MAY NEED TO ADD ENHANCED WORDING
IN HWO DUE TO POSSIBLE NCFRB/LOW TOPPED SQ LINE RACING ACRS THE
AREA DURING THE PRE-DAWN AND MORNING HOURS FRI. THE SYSTEM IS
PROGRESSIVE WHICH WILL LIMIT HVY RAIN POTNL/FLOOD THREAT...HOWEVER
ICE JAM EFFECTS COULD BE A CONCERN. ATTM DO NOT ANTICIPATE RAPID
SNOWMELT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS COLD FRONT SLIDES ACROSS ON FRI...PRECIP WILL PUSH EASTWARD
AND COOLER AIR WILL FILTER BACK INTO THE REGION. GFS/ECMWF NOW IN
QUITE GOOD ALIGNMENT WITH MAIN FEATURES AS THIS SYSTEM
EVOLVES...WITH PRECIP ENDING BY LUNCHTIME FRI.
BROAD TROUGH DEVELOPS ACROSS EASTERN 2/3RDS OF U.S. FOR THE
WEEKEND...GIVING US A SLOW AND STEADY RETURN BACK TO SLIGHTLY
BELOW NORMAL TEMPERATURES. WEAK FRONT PUSHES THROUGH MID-WEEKEND
THAT MAY BRING LIGHT ACCUMS OF SNOW. OTHERWISE...NO BIG SYSTEMS ON
THE HORIZON. SNOWFLAKES WILL LINGER OVER THE WESTERN/NORTHERN
HIGHER TERRAIN IN PERSISTENT NW/W FLOW.
AS FAR AS THE SNOW COVER AND RIVER ICE...WARMING TREND LATE THIS
WEEK WILL BE FAIRLY SHORT-LIVED...SO MELTING OF SNOW AND ICE WILL
REMAIN GRADUAL...WHICH SHOULD KEEP POTENTIAL FOR WIDESPREAD
PROBLEMS LOW.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRESSURE...CLEAR SKIES...LIGHT WINDS AND SNOWPACK HAVE ALLOWED
FOR FOG/MIST ACROSS SOUTHEASTERN AND CENTRAL PA OVERNIGHT. THE
THICKEST FOG WAS AT LNS...AND THAT HAS SINCE LIFTED. THERE IS A
CHANCE FOR FOG AT LNS BETWEEN 11Z-15Z...OUT AHEAD OF THE NEXT BAND
OF PRECIPITATION. EXPECT FOG/MIST AT UNV...MDT AND LNS AND SHOULD
CONTINUE THROUGH MID MORNING.
PRECIP ASSOCIATED WITH THE APPROACHING COLD FRONT WILL BEGIN
MOVING INTO SOUTHWESTERN AREAS AROUND OR JUST BEFORE
DAWN...PROBABLY IN THE FORM OF FREEZING RAIN/DRIZZLE OR A LIGHT
WINTRY MIX. MOST TERMINALS WILL LIKELY EXPERIENCE A LIGHT ICING
ISSUE FOR A FEW HOURS AS THE PRECIP MOVES INTO THE REGION. THE
THREAT FOR ICING SHOULD DIMINISH BY MID TO LATE MORNING AS
TEMPERATURES RECOVER SLOWLY ABOVE FREEZING. MVFR/IFR CAN BE
EXPECTED WITH THE COMBINATION OF THE MILDER AIR AND LIGHT PRECIP
MOVING IN OVER OUR DEEP SNOW PACK.
THE COLD FRONT SHOULD MOVE THROUGH THE AREA BY EARLY TO MID
AFTERNOON...FOLLOWED BY A COOLER AND DRIER NW FLOW IN THE WAKE OF
THE FRONT. THERE COULD BE SOME LINGERING MVFR/IFR IN SCATTERED
RAIN OR SNOW SHOWERS...BUT THESE WILL BE VERY BRIEF AND CONFINED
TO THE WESTERN MOUNTAINS.
OUTLOOK...
THU...MVFR/IFR LIKELY WITH SHOWERS AND FOG.
FRI...SHRA/REDUCED CIGS LIKELY.
SAT...NO SIG WX EXPECTED.
SUN...MVFR/SCT SHSN NW. MAINLY VFR ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR PAZ006-012-037-
041-042-045-046-049>053-057>059.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ005-
010-011-017>019-025>028-034>036-056-063>066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
909 PM CST THU FEB 20 2014
.UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE WIND ADVISORY
FOR LOCATIONS ALONG AND WEST OF THE I-65 CORRIDOR AND TO REMOVE
COUNTIES FROM TORNADO WATCH 11 THAT WAS ALLOWED TO EXPIRE.
&&
.PREV DISCUSSION.../ISSUED 714 PM CST THU FEB 20 2014/
UPDATE...
UPDATED THE SUITE OF FORECAST PRODUCTS TO MENTION IMPACTS OF
TORNADO WATCH NUMBER 16 UNTIL 3 AM.
PREV DISCUSSION... /ISSUED 604 PM CST THU FEB 20 2014/
UPDATE...
UPDATED TO REMOVE THROUGH LATE AFTERNOON GROUPING FROM ZONE
FORECAST PRODUCT.
PREV DISCUSSION.../ISSUED 525 PM CST THU FEB 20 2014/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION...00Z AVIATION DISCUSSION.
ANTICIPATE MULTIPLE AMENDMENTS THRU AT LEAST 21/06Z PER ACTUAL
FLUCTUATIONS IN WINDS...CEILINGS...TSTM...AND RAINFALL IMPACTS.
ALONG WITH STRONG PRESSURE GRADIENT CONCERNS ALONG AND AHEAD OF
EXPECTED SQUALL LINE EXPECTED TO MOVE ACROSS MID STATE...EMBEDDED
SVR TSTMS COULD PRODUCE VRB WIND GUSTS AT OR GREATER THAN 50KTS.
AVIATION INTEREST NEED TO PAY SPECIAL ATTENTION TO RAPIDLY
CHANGING WX CONDITIONS THRU THE MID STATE THRU AT LEAST 21/06Z.
WILL GO WITH A TIME FRAME OF POTENTIAL IMPACTS CKV 21/00Z-21/02Z...
BNA 21/01Z-21/03Z...AND CSV 21/03Z-21/05Z...WITH PREDOMINATE MVFR
CEILINGS AND IFR VSBYS DURING THESE TIME PERIODS.
PREV DISCUSSION.../ISSUED 447 PM CST THU FEB 20 2014/
DISCUSSION...
UPDATED TO BREAK OUT LATE AFTERNOON GROUPING IN THE ZONE FORECAST
PRODUCT FOR GREATER CLARIFICATION FOR FORECAST THROUGH LATE
AFTERNOON HOURS AND FOR TONIGHT.
PREV DISCUSSION.../ISSUED 348 PM CST THU FEB 20 2014/
POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT AS
STRONG COLD FRONT SWEEPS THROUGH...
SHORT TERM...AS OF 330 PM, THUNDERSTORMS WERE ALREADY DEVELOPING
OVER THE EXTREME NORTHWESTERN PART OF OUR CWA. INTERMEDIATE 20Z
OHX SOUNDING STILL SHOWED A WARM NOSE AROUND 700MB, AS DID THE
EARLIER 12Z SOUNDING. HOWEVER, FORECAST RUC SOUNDINGS CONTINUE TO
SUGGEST AN EROSION OF THE INHIBITING NOSE THROUGH OUR NORTHWESTERN
COUNTIES, AS INDICATED BY THE ONGOING THUNDERSTORMS.
RECORD WARMTH WAS RECORDED OVER THE MID STATE TODAY, WITH
NASHVILLE EQUALING A RECORD HIGH OF 78 DEGREES. WINDS CONTINUE TO
GUST TO BETWEEN 35 AND 40 MPH OVER OUR WESTERN COUNTIES, IN
ADVANCE OF THE STORMS.
A TORNADO WATCH IS IN EFFECT UNTIL 9PM FOR OUR MOST WESTERN
COUNTIES, AND IT WOULD NOT BE SURPRISING TO SEE SEVERE WEATHER
WATCHES EXTENDED INTO OTHER PARTS OF THE MID STATE LATER THIS
EVENING.
STILL LOOKS LIKE THE STRONG COLD FRONT, NOW LOCATED BACK OVER
SOUTHEASTERN MISSOURI, WILL SWEEP RAPIDLY EASTWARD ACROSS THE MID
STATE BETWEEN 00Z AND 06Z THIS EVENING, WITH AN ATTENDANT SQUALL
LINE, AND THE EXPECTATION FOR SOME DAMAGING STRAIGHT LINE WINDS,
LARGE HAIL, AND POSSIBLY A FEW TORNADOES AS WELL.
THERE WILL BE A SLIGHT CHANCE FOR LINGERING SHOWERS IN THE
MORNING, ALONG THE CUMBERLAND PLATEAU. OTHERWISE, TOMORROW SHOULD
BRING SOME DRIER AND MUCH QUIETER WEATHER, WITH AFTERNOON HIGHS
IN THE 50S.
UNSEASONABLY MILD TEMPERATURES REMAIN OVER THE UPCOMING WEEKEND,
WITH DAYTIME HIGHS FORECAST TO BE IN THE 60S BOTH SATURDAY AND
SUNDAY.
LONG TERM...A GENERAL COOL DOWN OCCURS NEXT WEEK, WITH HIGHS
FALLING TO THE 40S AND 50S MONDAY AND TUESDAY AND INTO THE 40S FOR
WEDNESDAY AND THURSDAY. HAVE TRENDED TOWARD THE COOLER ECMWF FOR
THE LATTER PERIODS, AS BOTH GFS AND ECMWF SUGGEST SOME PRETTY GOOD
DEEPENING OF UPPER TROUGH BY NEXT WEDNESDAY AND THURSDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-029>034-
063>066-077>080.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
714 PM CST THU FEB 20 2014
.UPDATE...
UPDATED THE SUITE OF FORECAST PRODUCTS TO MENTION IMPACTS OF
TORNADO WATCH NUMBER 16 UNTIL 3 AM.
&&
.PREV DISCUSSION... /ISSUED 604 PM CST THU FEB 20 2014/
UPDATE...
UPDATED TO REMOVE THROUGH LATE AFTERNOON GROUPING FROM ZONE
FORECAST PRODUCT.
PREV DISCUSSION.../ISSUED 525 PM CST THU FEB 20 2014/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION...00Z AVIATION DISCUSSION.
ANTICIPATE MULTIPLE AMENDMENTS THRU AT LEAST 21/06Z PER ACTUAL
FLUCTUATIONS IN WINDS...CEILINGS...TSTM...AND RAINFALL IMPACTS.
ALONG WITH STRONG PRESSURE GRADIENT CONCERNS ALONG AND AHEAD OF
EXPECTED SQUALL LINE EXPECTED TO MOVE ACROSS MID STATE...EMBEDDED
SVR TSTMS COULD PRODUCE VRB WIND GUSTS AT OR GREATER THAN 50KTS.
AVIATION INTEREST NEED TO PAY SPECIAL ATTENTION TO RAPIDLY
CHANGING WX CONDITIONS THRU THE MID STATE THRU AT LEAST 21/06Z.
WILL GO WITH A TIME FRAME OF POTENTIAL IMPACTS CKV 21/00Z-21/02Z...
BNA 21/01Z-21/03Z...AND CSV 21/03Z-21/05Z...WITH PREDOMINATE MVFR
CEILINGS AND IFR VSBYS DURING THESE TIME PERIODS.
PREV DISCUSSION.../ISSUED 447 PM CST THU FEB 20 2014/
DISCUSSION...
UPDATED TO BREAK OUT LATE AFTERNOON GROUPING IN THE ZONE FORECAST
PRODUCT FOR GREATER CLARIFICATION FOR FORECAST THROUGH LATE
AFTERNOON HOURS AND FOR TONIGHT.
PREV DISCUSSION.../ISSUED 348 PM CST THU FEB 20 2014/
POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT AS
STRONG COLD FRONT SWEEPS THROUGH...
SHORT TERM...AS OF 330 PM, THUNDERSTORMS WERE ALREADY DEVELOPING
OVER THE EXTREME NORTHWESTERN PART OF OUR CWA. INTERMEDIATE 20Z
OHX SOUNDING STILL SHOWED A WARM NOSE AROUND 700MB, AS DID THE
EARLIER 12Z SOUNDING. HOWEVER, FORECAST RUC SOUNDINGS CONTINUE TO
SUGGEST AN EROSION OF THE INHIBITING NOSE THROUGH OUR NORTHWESTERN
COUNTIES, AS INDICATED BY THE ONGOING THUNDERSTORMS.
RECORD WARMTH WAS RECORDED OVER THE MID STATE TODAY, WITH
NASHVILLE EQUALING A RECORD HIGH OF 78 DEGREES. WINDS CONTINUE TO
GUST TO BETWEEN 35 AND 40 MPH OVER OUR WESTERN COUNTIES, IN
ADVANCE OF THE STORMS.
A TORNADO WATCH IS IN EFFECT UNTIL 9PM FOR OUR MOST WESTERN
COUNTIES, AND IT WOULD NOT BE SURPRISING TO SEE SEVERE WEATHER
WATCHES EXTENDED INTO OTHER PARTS OF THE MID STATE LATER THIS
EVENING.
STILL LOOKS LIKE THE STRONG COLD FRONT, NOW LOCATED BACK OVER
SOUTHEASTERN MISSOURI, WILL SWEEP RAPIDLY EASTWARD ACROSS THE MID
STATE BETWEEN 00Z AND 06Z THIS EVENING, WITH AN ATTENDANT SQUALL
LINE, AND THE EXPECTATION FOR SOME DAMAGING STRAIGHT LINE WINDS,
LARGE HAIL, AND POSSIBLY A FEW TORNADOES AS WELL.
THERE WILL BE A SLIGHT CHANCE FOR LINGERING SHOWERS IN THE
MORNING, ALONG THE CUMBERLAND PLATEAU. OTHERWISE, TOMORROW SHOULD
BRING SOME DRIER AND MUCH QUIETER WEATHER, WITH AFTERNOON HIGHS
IN THE 50S.
UNSEASONABLY MILD TEMPERATURES REMAIN OVER THE UPCOMING WEEKEND,
WITH DAYTIME HIGHS FORECAST TO BE IN THE 60S BOTH SATURDAY AND
SUNDAY.
LONG TERM...A GENERAL COOL DOWN OCCURS NEXT WEEK, WITH HIGHS
FALLING TO THE 40S AND 50S MONDAY AND TUESDAY AND INTO THE 40S FOR
WEDNESDAY AND THURSDAY. HAVE TRENDED TOWARD THE COOLER ECMWF FOR
THE LATTER PERIODS, AS BOTH GFS AND ECMWF SUGGEST SOME PRETTY GOOD
DEEPENING OF UPPER TROUGH BY NEXT WEDNESDAY AND THURSDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-029>034-
063>066-077>080.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
604 PM CST THU FEB 20 2014
.UPDATE...
UPDATED TO REMOVE THROUGH LATE AFTERNOON GROUPING FROM ZONE
FORECAST PRODUCT.
&&
.PREV DISCUSSION.../ISSUED 525 PM CST THU FEB 20 2014/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION...00Z AVIATION DISCUSSION.
ANTICIPATE MULTIPLE AMENDMENTS THRU AT LEAST 21/06Z PER ACTUAL
FLUCTUATIONS IN WINDS...CEILINGS...TSTM...AND RAINFALL IMPACTS.
ALONG WITH STRONG PRESSURE GRADIENT CONCERNS ALONG AND AHEAD OF
EXPECTED SQUALL LINE EXPECTED TO MOVE ACROSS MID STATE...EMBEDDED
SVR TSTMS COULD PRODUCE VRB WIND GUSTS AT OR GREATER THAN 50KTS.
AVIATION INTEREST NEED TO PAY SPECIAL ATTENTION TO RAPIDLY
CHANGING WX CONDITIONS THRU THE MID STATE THRU AT LEAST 21/06Z.
WILL GO WITH A TIME FRAME OF POTENTIAL IMPACTS CKV 21/00Z-21/02Z...
BNA 21/01Z-21/03Z...AND CSV 21/03Z-21/05Z...WITH PREDOMINATE MVFR
CEILINGS AND IFR VSBYS DURING THESE TIME PERIODS.
PREV DISCUSSION.../ISSUED 447 PM CST THU FEB 20 2014/
DISCUSSION...
UPDATED TO BREAK OUT LATE AFTERNOON GROUPING IN THE ZONE FORECAST
PRODUCT FOR GREATER CLARIFICATION FOR FORECAST THROUGH LATE
AFTERNOON HOURS AND FOR TONIGHT.
PREV DISCUSSION.../ISSUED 348 PM CST THU FEB 20 2014/
POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT AS
STRONG COLD FRONT SWEEPS THROUGH...
SHORT TERM...AS OF 330 PM, THUNDERSTORMS WERE ALREADY DEVELOPING
OVER THE EXTREME NORTHWESTERN PART OF OUR CWA. INTERMEDIATE 20Z
OHX SOUNDING STILL SHOWED A WARM NOSE AROUND 700MB, AS DID THE
EARLIER 12Z SOUNDING. HOWEVER, FORECAST RUC SOUNDINGS CONTINUE TO
SUGGEST AN EROSION OF THE INHIBITING NOSE THROUGH OUR NORTHWESTERN
COUNTIES, AS INDICATED BY THE ONGOING THUNDERSTORMS.
RECORD WARMTH WAS RECORDED OVER THE MID STATE TODAY, WITH
NASHVILLE EQUALING A RECORD HIGH OF 78 DEGREES. WINDS CONTINUE TO
GUST TO BETWEEN 35 AND 40 MPH OVER OUR WESTERN COUNTIES, IN
ADVANCE OF THE STORMS.
A TORNADO WATCH IS IN EFFECT UNTIL 9PM FOR OUR MOST WESTERN
COUNTIES, AND IT WOULD NOT BE SURPRISING TO SEE SEVERE WEATHER
WATCHES EXTENDED INTO OTHER PARTS OF THE MID STATE LATER THIS
EVENING.
STILL LOOKS LIKE THE STRONG COLD FRONT, NOW LOCATED BACK OVER
SOUTHEASTERN MISSOURI, WILL SWEEP RAPIDLY EASTWARD ACROSS THE MID
STATE BETWEEN 00Z AND 06Z THIS EVENING, WITH AN ATTENDANT SQUALL
LINE, AND THE EXPECTATION FOR SOME DAMAGING STRAIGHT LINE WINDS,
LARGE HAIL, AND POSSIBLY A FEW TORNADOES AS WELL.
THERE WILL BE A SLIGHT CHANCE FOR LINGERING SHOWERS IN THE
MORNING, ALONG THE CUMBERLAND PLATEAU. OTHERWISE, TOMORROW SHOULD
BRING SOME DRIER AND MUCH QUIETER WEATHER, WITH AFTERNOON HIGHS
IN THE 50S.
UNSEASONABLY MILD TEMPERATURES REMAIN OVER THE UPCOMING WEEKEND,
WITH DAYTIME HIGHS FORECAST TO BE IN THE 60S BOTH SATURDAY AND
SUNDAY.
LONG TERM...A GENERAL COOL DOWN OCCURS NEXT WEEK, WITH HIGHS
FALLING TO THE 40S AND 50S MONDAY AND TUESDAY AND INTO THE 40S FOR
WEDNESDAY AND THURSDAY. HAVE TRENDED TOWARD THE COOLER ECMWF FOR
THE LATTER PERIODS, AS BOTH GFS AND ECMWF SUGGEST SOME PRETTY GOOD
DEEPENING OF UPPER TROUGH BY NEXT WEDNESDAY AND THURSDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-029>034-
063>066-077>080.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
525 PM CST THU FEB 20 2014
.UPDATE...FOR 00Z AVIATION DISCUSSION.
&&
.AVIATION...00Z AVIATION DISCUSSION.
ANTICIPATE MULTIPLE AMENDMENTS THRU AT LEAST 21/06Z PER ACTUAL
FLUCTUATIONS IN WINDS...CEILINGS...TSTM...AND RAINFALL IMPACTS.
ALONG WITH STRONG PRESSURE GRADIENT CONCERNS ALONG AND AHEAD OF
EXPECTED SQUALL LINE EXPECTED TO MOVE ACROSS MID STATE...EMBEDDED
SVR TSTMS COULD PRODUCE VRB WIND GUSTS AT OR GREATER THAN 50KTS.
AVIATION INTEREST NEED TO PAY SPECIAL ATTENTION TO RAPIDLY
CHANGING WX CONDITIONS THRU THE MID STATE THRU AT LEAST 21/06Z.
WILL GO WITH A TIME FRAME OF POTENTIAL IMPACTS CKV 21/00Z-21/02Z...
BNA 21/01Z-21/03Z...AND CSV 21/03Z-21/05Z...WITH PREDOMINATE MVFR
CEILINGS AND IFR VSBYS DURING THESE TIME PERIODS.
&&
.PREV DISCUSSION.../ISSUED 447 PM CST THU FEB 20 2014/
DISCUSSION...
UPDATED TO BREAK OUT LATE AFTERNOON GROUPING IN THE ZONE FORECAST
PRODUCT FOR GREATER CLARIFICATION FOR FORECAST THROUGH LATE
AFTERNOON HOURS AND FOR TONIGHT.
PREV DISCUSSION.../ISSUED 348 PM CST THU FEB 20 2014/
.POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT AS
STRONG COLD FRONT SWEEPS THROUGH...
SHORT TERM...AS OF 330 PM, THUNDERSTORMS WERE ALREADY DEVELOPING
OVER THE EXTREME NORTHWESTERN PART OF OUR CWA. INTERMEDIATE 20Z
OHX SOUNDING STILL SHOWED A WARM NOSE AROUND 700MB, AS DID THE
EARLIER 12Z SOUNDING. HOWEVER, FORECAST RUC SOUNDINGS CONTINUE TO
SUGGEST AN EROSION OF THE INHIBITING NOSE THROUGH OUR NORTHWESTERN
COUNTIES, AS INDICATED BY THE ONGOING THUNDERSTORMS.
RECORD WARMTH WAS RECORDED OVER THE MID STATE TODAY, WITH
NASHVILLE EQUALING A RECORD HIGH OF 78 DEGREES. WINDS CONTINUE TO
GUST TO BETWEEN 35 AND 40 MPH OVER OUR WESTERN COUNTIES, IN
ADVANCE OF THE STORMS.
A TORNADO WATCH IS IN EFFECT UNTIL 9PM FOR OUR MOST WESTERN
COUNTIES, AND IT WOULD NOT BE SURPRISING TO SEE SEVERE WEATHER
WATCHES EXTENDED INTO OTHER PARTS OF THE MID STATE LATER THIS
EVENING.
STILL LOOKS LIKE THE STRONG COLD FRONT, NOW LOCATED BACK OVER
SOUTHEASTERN MISSOURI, WILL SWEEP RAPIDLY EASTWARD ACROSS THE MID
STATE BETWEEN 00Z AND 06Z THIS EVENING, WITH AN ATTENDANT SQUALL
LINE, AND THE EXPECTATION FOR SOME DAMAGING STRAIGHT LINE WINDS,
LARGE HAIL, AND POSSIBLY A FEW TORNADOES AS WELL.
THERE WILL BE A SLIGHT CHANCE FOR LINGERING SHOWERS IN THE
MORNING, ALONG THE CUMBERLAND PLATEAU. OTHERWISE, TOMORROW SHOULD
BRING SOME DRIER AND MUCH QUIETER WEATHER, WITH AFTERNOON HIGHS
IN THE 50S.
UNSEASONABLY MILD TEMPERATURES REMAIN OVER THE UPCOMING WEEKEND,
WITH DAYTIME HIGHS FORECAST TO BE IN THE 60S BOTH SATURDAY AND
SUNDAY.
LONG TERM...A GENERAL COOL DOWN OCCURS NEXT WEEK, WITH HIGHS
FALLING TO THE 40S AND 50S MONDAY AND TUESDAY AND INTO THE 40S FOR
WEDNESDAY AND THURSDAY. HAVE TRENDED TOWARD THE COOLER ECMWF FOR
THE LATTER PERIODS, AS BOTH GFS AND ECMWF SUGGEST SOME PRETTY GOOD
DEEPENING OF UPPER TROUGH BY NEXT WEDNESDAY AND THURSDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-029>034-
063>066-077>080.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
31
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1204 PM CST WED FEB 19 2014
.AVIATION...
THE MVFR STRATUS LAYER AT KCDS HAS BEEN QUITE PERSISTENT...WITH
EACH HOURLY RUN OF THE RAP CONTINUING TO DELAY CLEARING UNTIL THE
NEXT HOUR. VIEWING OF THE STRATUS LAYER VIA SATELLITE DIFFERENCE
CHANNELS HAS BEEN HAMPERED BY THE THICKER CLOUD DECK BLOCKING FROM
ALOFT. ALSO...IT HAS BECOME LESS OBVIOUS IF SURFACE SOUTHWEST WIND
FLOW WILL BE ABLE TO DEVELOP ANYTIME THIS AFTERNOON AT KCDS. FOR
THIS FORECAST WE WILL SIDE WITH THE RAP MAINTAINING AN EAST OR
SOUTHEAST LOW LEVEL COMPONENT THROUGH THE AFTERNOON...THOUGH BREAK
OUT THE MVFR CLOUD LAYER BY 19Z. THE WEST TO SOUTHWEST COMPONENT
AT KLBB ALSO IS A BIT DELAYED WITH ONLY VERY WEAK SURFACE PRESSURE
FALLS CURRENTLY NEAR THE NEW MEXICO BORDER...BUT MORE BROAD
PRESSURE FALLS EXPECTED TO EXPAND THROUGH THE AREA THIS AFTERNOON
WHICH SHOULD GENERATE MORE WESTERLY COMPONENT BY MID TO LATE IN
THE AFTERNOON. THE NEXT EVENT WILL BE PASSAGE OF A VIGOROUS COLD
FRONT LATE IN THE NIGHT...NOT MUCH TO DIFFER WITH TIMING OF THE
FRONT. SPEEDS SHOULD INCREASE AROUND DAYBREAK THURSDAY AS WINDS
VEER SLIGHTLY MORE TO THE NORTH. ADDED A MENTION OF A MINOR
VISIBILITY REDUCTION FOR BLOWING DUST AT KLBB AFTER DAYBREAK
THURSDAY DUE TO FAVORABLE COMPOENENT...SPEEDS...AND TIME OF YEAR.
RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 516 AM CST WED FEB 19 2014/
AVIATION...
VFR TO CONTINUE NEXT 24 HOURS. PRESSURE GRADIENT WILL INCREASE
THIS EVENING AS SURFACE TROUGH ACROSS ERN NM BEGINS TO PUSH
EASTWARD. STRONG COLD FRONT WILL BRING WINDY CONDITIONS TO BOTH
TERMINALS EARLY THURSDAY MORNING.
PREV DISCUSSION... /ISSUED 240 AM CST WED FEB 19 2014/
SHORT TERM...
THROUGH 21/00Z. ZONAL FLOW ACROSS THE REGION WILL BECOME MORE
SOUTHWESTERLY AS TROUGH AMPLIFIES ACROSS THE ROCKIES TODAY AND
TONIGHT. PRIMARY CONCERN WILL BE WIND SPEEDS AND SOME LIMITED
POTENTIAL FOR FIRE WEATHER THIS AFTERNOON BEFORE A STRONG COLD FRONT
ENTERS THE PICTURE EARLY THURSDAY MORNING WITH YET MORE WIND.
PRIMARY WIND DRIVER TODAY OUT EAST WILL BE THE SURFACE PRESSURE
GRADIENT AS INVERSION ALOFT FROM ABOUT H9 TO H8 LIMITS POTENTIAL
ACROSS THE EASTERN ROLLING PLAINS. FURTHER WEST...A NICE ADIABATIC
LAPSE RATE IS PROGGED UP TO ABOUT 750MB AND THIS SHOULD ALLOW
EFFICIENT MISSING LATER THIS AFTERNOON WITH SPEEDS UP IN THE 15-20
MPH RANGE. SEE FIRE WEATHER SECTION BELOW. THESE WINDS WILL
CONTINUE TO INCREASE TO 20-25 MPH DURING THE EVENING AS SURFACE LOW
KICKS EASTWARD IN RESPONSE TO AFOREMENTIONED DEEPENING UPPER LEVEL
TROUGH. THEN...A STRONGLY FORCED COLD FRONT SHOULD ENTER THE REGION
AND POSSIBLY CLEAR THE ENTIRE CWFA BY 12Z THURSDAY MORNING. WINDS
BEHIND THIS FRONT LOOK TO BE QUITE GUSTY AND MAY MEET ADVISORY
CRITERIA.
LONG TERM...
THE UA TROUGH RESPONSIBLE FOR THE RATHER BREEZY CONDITIONS
ANTICIPATED FOR LATE TONIGHT INTO TOMORROW...WILL BE EAST OF THE
SOUTHERN PLAINS BY TOMORROW EVENING...AND THUS SLIGHT W-NW FLOW
ALOFT WILL SETTLE BACK TO SEMI-ZONAL FLOW BY FRI. THE EXTENDED
FORECAST WILL BE PUNCTUATED BY SEVERAL COLD FRONTAL PASSAGES THAT
ARE ASSOCIATED WITH A SERIES OF DISTURBANCES PASSING TO OUR NORTH.
THE FIRST OF THESE COLD FRONTS WILL OCCUR ON SAT...AND IS EXHIBITED
TO BE RELATIVELY WEAK AS 850 MB TEMPS REMAIN WELL ABOVE 0 DEGREES C
WITH RELATIVELY LIGHT WIND SPEEDS. LONG TERM SOLUTIONS SHOW THIS
FRONT TO WASH OUT OVER THE CWA HENCE WINDS WILL RETURN TO A S-SE
COMPONENT BY THE EVENING-OVERNIGHT HOURS. THIS APPEARS TO BE
SHORT-LIVED AS YET ANOTHER FRONT IMPINGES ON THE REGION ON SUNDAY.
WINDS ARE A TAD BIT BREEZIER BEHIND THIS COLD FRONTAL PASSAGE /10-15
MPH/ IN ADDITION TO BEING COLDER AS 850 MB TEMPS DROP TO A RANGE OF
2-14 DEGREES C DURING THE DAY. WILL THEREFORE SEE HIGHS DROP FROM
MAINLY THE 60S ON SAT TO THE 50S /WITH A FEW 60S/ SUN. QUITE A BIT
OF DRY AIR IN THE LOW-MID LEVELS WOULD NEED TO BE OVERCOME IN ORDER
FOR PRECIP TO DEVELOP...THUS LACK OF QPF SIGNALS APPEAR VALID.
EARLY NEXT WEEK...AMPLIFIED UA RIDGING ACROSS THE WRN CONUS WILL
PROMOTE A SLIGHT W-NW FLOW ALOFT ACROSS THE SOUTHERN PLAINS. LONG
TERM SOLUTIONS HINT AT THIS FLOW ALOFT POSSIBLY BEING VEERED JUST
ENOUGH TO ALLOW FOR A COLDER AIR INTRUSION IN ASSOCIATED WITH
ANOTHER BREEZY FROPA ON TUE...AS 850 MB TEMPS DROP TO SLIGHTLY BELOW
0 DEGREES C /SUGGESTIVE OF HIGHS ONLY IN THE 40S/. THOUGH...THE MUCH
COLDER AIR IS PROJECTED TO REMAIN ENTRENCHED ACROSS THE GREAT LAKES
REGION AND THE NERN CONUS. FURTHERMORE...PROGGED SOUNDINGS DISPLAYED
MOISTENING LOW LEVELS TUE AS PWATS MARGINALLY INCREASE TO AOA 0.50
INCHES /ESPECIALLY OFF THE CAPROCK/. HOWEVER...MID LEVELS ARE RATHER
DRY AND IT IS NO WONDER QPF VALUES ARE SHOWN TO BE RATHER LIGHT.
WILL NOT INCREASE POPS BEYOND 5 PERCENT POPS ON TUE ATTM.
ALTHOUGH THE EXTENDED FORECAST IS PLAGUED WITH FRONTAL
PASSAGES...THERE WILL BE A FEW DAYS WHERE NEARBY SFC LEE TROUGHING
ENCOURAGES MODEST SWRLY BREEZES AND THUS WARMER TEMPS /LOWER TO UPPER
60S/...WHICH WILL OCCUR ON FRI AND MON.
FIRE WEATHER...
DAY 1...
PRESENT INDICATIONS SUGGEST THAT WHILE WE WILL HAVE PERIODS OF QUITE
DRY CONDITIONS AND WINDY CONDITIONS...THE OVERLAP OF THESE TWO
PARAMETERS APPEARS TO BE MINIMAL. GIVEN THE REPORTED FIRES OF THE
PAST COUPLE OF DAYS...THERE IS LITTLE DOUBT THAT FUELS ARE QUITE
VOLATILE. GIVEN THE WIND SPEEDS IN THE 15-20 MPH RANGE THIS
AFTERNOON ALONG WITH MIN RH VALUES IN THE 10-15 PC RANGE...WILL
ELECT TO ISSUE RFD GENERALLY WEST OF THE CAPROCK ESCARPMENT.
ADJACENT AREAS OF THE ROLLING PLAINS MAY ALSO BE ELEVATED THOUGH
WIND SPEEDS ARE EXPECTED TO BE A BIT LIGHTER OUT EAST. FOR THIS
AFTERNOON...MOST FAVORABLE FIRE WX CONDITIONS LOOK TO BE ACROSS THE
SOUTHWESTERN SOUTH PLAINS. VERY LITTLE IN THE WAY OF OVERNIGHT
RECOVERY IS EXPECTED WITH RH VALUES REMAINING UNDER 30 PCT.
DAY2...
ELEVATED FIRE WEATHER CONDITIONS WILL BE POSSIBLE MAINLY EAST OF THE
I-27 CORRIDOR DURING THE MORNING HOURS AS GUSTY WINDS PREVAIL BEHIND
A FAST MOVING COLD FRONT. THE BEST DRYING...HOWEVER...APPEARS TO
OCCUR AFTER THE WINDS BEGIN TO SUBSIDE IN THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 72 36 53 22 64 / 0 0 0 0 0
TULIA 71 39 52 25 63 / 0 0 0 0 0
PLAINVIEW 75 41 52 26 65 / 0 0 0 0 0
LEVELLAND 79 43 56 28 69 / 0 0 0 0 0
LUBBOCK 79 43 55 29 67 / 0 0 0 0 0
DENVER CITY 80 41 58 32 69 / 0 0 0 0 0
BROWNFIELD 82 43 57 29 69 / 0 0 0 0 0
CHILDRESS 72 45 56 30 67 / 0 0 0 0 0
SPUR 81 47 57 29 68 / 0 0 0 0 0
ASPERMONT 83 48 57 30 68 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1006 AM CST WED FEB 19 2014
.UPDATE...
ALLOWED THE DENSE FOG ADVISORY TO EXPIRE AT 10AM AND REMOVED THE
ADVISORY FROM THE ZONES. A COUPLE LOCATIONS WERE STILL AT ONE
QUARTER MILE...HOWEVER VISIBILITIES WERE GENERALLY ON THE INCREASE.
THE SHORT TERM FORECAST WILL ADDRESS THE LOCALIZED LOWER VISIBILITIES
FOR THE NEXT HOUR. OTHERWISE THE ONGOING FORECAST IS ON TRACK AND
NO MAJOR CHANGES NEEDED AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 613 AM CST WED FEB 19 2014/
UPDATE...
WE HAVE UPDATED THE FORECAST TO ISSUE A DENSE FOG ADVISORY FOR
AREAS GENERALLY ALONG AND WEST OF A LLANO TO NEW BRAUNFELS TO SAN
ANTONIO TO PLEASANTON LINE. LIGHT WINDS AND PLENTY OF LOW LEVEL
MOISTURE HAS LED TO PATCHY...DENSE FOG ACROSS ROUGHLY THE WESTERN
2/3 OF SOUTH CENTRAL TEXAS THIS MORNING. IMPROVING CONDITIONS ARE
EXPECTED AFTER 10 AM AS WINDS AND TEMPERATURES BEGIN TO INCREASE.
PREV DISCUSSION... /ISSUED 354 AM CST WED FEB 19 2014/
SHORT TERM (TODAY THROUGH THURSDAY)...
SURFACE OBSERVATIONS AND SATELLITE IMAGERY SHOW FOG AND LOW CLOUDS
ARE CURRENTLY IN PLACE ACROSS SOUTH CENTRAL TEXAS. BASED ON RECENT
TRENDS AND THE LATEST HI-RES RUC MODEL...WE HAVE INCLUDED A
MENTION OF PATCHY...DENSE FOG ACROSS THE HILL COUNTRY AND SOUTHERN
EDWARDS PLATEAU. THE FOG IS EXPECTED TO DECREASE BY MID-MORNING AS
SOUTHERLY WINDS AND DAYTIME HEATING COMMENCE. AFTERNOON
TEMPERATURES WILL WARM TO ABOVE NORMAL LEVELS TODAY... WITH HIGHS
RANGING FROM THE UPPER 80S ALONG THE RIO GRANDE TO UPPER 70S ALONG
THE HIGHWAY 77 CORRIDOR. MOIST CONDITIONS REMAIN IN PLACE TONIGHT
AND WE/LL CONTINUE TO MENTION FOG AND DRIZZLE ACROSS MOST AREAS. A
PACIFIC COLD FRONT WILL MOVE THROUGH THE REGION ON THURSDAY. IN
ADVANCE OF THE FRONT...CAN/T RULE OUT SOME LIGHT MORNING SHOWERS
ALONG AND EAST OF THE I-35 CORRIDOR. WE/LL ALSO CONTINUE TO
MENTION A SLIGHT CHANCE FOR AFTERNOON THUNDERSTORMS EAST OF I-35
AS THE COLD FRONT WILL BE ACROSS THIS REGION DURING PEAK HEATING.
THE COLD FRONT WILL ALSO BRING AN INCREASE IN FIRE WEATHER
CONCERNS FOR AREAS ALONG AND WEST OF I-35. PLEASE SEE THE BELOW
FIRE WEATHER SECTION FOR MORE INFORMATION.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
WINDS WILL DECREASE THURSDAY NIGHT AS SKIES REMAIN MOSTLY CLEAR.
THIS ALONG WITH DRY AIR WILL ALLOW TEMPERATURES TO DROP INTO THE
LOWER 30S ACROSS THE HILL COUNTRY TO THE MID 40S COASTAL PLAINS.
SOUTHERLY FLOW IN THE LOW-LEVELS RESUMES ON FRIDAY AS ZONAL FLOW
ALOFT PERSISTS. A WARMING TREND IS EXPECTED SATURDAY AS THE LATEST
MEDIUM RANGE MODELS SHOW A COLD FRONT REMAINING NORTH OF THE
REGION. THERE IS SOME DISAGREEMENT AMONG THE MEDIUM RANGE MODELS
WITH REGARDS TO THE SOUTHWARD PROGRESS OF THE COLD FRONT ON
SUNDAY. FOR NOW...WILL SHOW SOME SLIGHTLY COOLER TEMPERATURES
NORTH OF I-10...WITH LITTLE CHANGE ELSEWHERE. THE FLOW ALOFT OVER
THE WESTERN U.S. WILL AMPLIFY EARLY NEXT WEEK...BUT DOES NOT
CHANGE SIGNIFICANTLY ACROSS THE SOUTHERN PLAINS. THIS PATTERN DOES
FAVOR PERIODIC COLD FRONTS MOVING INTO THE REGION AND WE/LL SHOW
SOME NEAR TO BELOW NORMAL TEMPERATURES ON TUESDAY. SOME LIGHT
SHOWERS ARE POSSIBLE EARLY NEXT WEEK...BUT OVERALL AMOUNTS AND
PRECIPITATION CHANCES WILL REMAIN LOW.
FIRE WEATHER...
CRITICAL TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE LIKELY FOR
AREAS MAINLY ALONG AND WEST OF THE I-35 CORRIDOR THURSDAY
AFTERNOON IN THE WAKE OF A PACIFIC COLD FRONT. RELATIVE HUMIDITIES
WILL DROP INTO THE TEENS WITH NORTH WINDS OF 15 TO 25 MPH AND
GUSTY FOLLOWING THE FRONTAL PASSAGE. ELEVATED FIRE WEATHER
CONDITIONS ARE POSSIBLE FRIDAY AFTERNOON MAINLY ALONG AND WEST OF
THE I-35 CORRIDOR AS RELATIVE HUMIDITIES AGAIN FALL INTO THE
TEENS WITH SOUTHERLY WINDS OF 10 TO 15 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 81 64 81 43 72 / - - 20 - -
AUSTIN BERGSTROM INTL AIRPORT 79 61 81 36 71 / - - 20 - -
NEW BRAUNFELS MUNI AIRPORT 80 61 83 39 73 / - - 20 - -
BURNET MUNI AIRPORT 78 60 76 37 69 / - - 20 - -
DEL RIO INTL AIRPORT 88 58 86 43 74 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 62 78 38 69 / - - 20 - -
HONDO MUNI AIRPORT 85 59 86 40 75 / - - 10 0 -
SAN MARCOS MUNI AIRPORT 79 62 81 39 71 / - - 20 - -
LA GRANGE - FAYETTE REGIONAL 78 64 79 42 69 / - 10 20 10 -
SAN ANTONIO INTL AIRPORT 82 63 85 44 74 / - - 10 - -
STINSON MUNI AIRPORT 82 62 86 43 73 / - - 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING
FOR THE FOLLOWING COUNTIES: BANDERA...BASTROP...BEXAR...BLANCO...
BURNET...CALDWELL...COMAL...DIMMIT...EDWARDS...FRIO...GILLESPIE...
GUADALUPE...HAYS...KENDALL...KERR...KINNEY...LLANO...MAVERICK...
MEDINA...REAL...TRAVIS...UVALDE...VAL VERDE...WILLIAMSON...ZAVALA.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...01
PUBLIC SERVICE/DATA COLLECTION...32
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
613 AM CST WED FEB 19 2014
.UPDATE...
WE HAVE UPDATED THE FORECAST TO ISSUE A DENSE FOG ADVISORY FOR
AREAS GENERALLY ALONG AND WEST OF A LLANO TO NEW BRAUNFELS TO SAN
ANTONIO TO PLEASANTON LINE. LIGHT WINDS AND PLENTY OF LOW LEVEL
MOISTURE HAS LED TO PATCHY...DENSE FOG ACROSS ROUGHLY THE WESTERN
2/3 OF SOUTH CENTRAL TEXAS THIS MORNING. IMPROVING CONDITIONS ARE
EXPECTED AFTER 10 AM AS WINDS AND TEMPERATURES BEGIN TO INCREASE.
&&
.PREV DISCUSSION... /ISSUED 354 AM CST WED FEB 19 2014/
SHORT TERM (TODAY THROUGH THURSDAY)...
SURFACE OBSERVATIONS AND SATELLITE IMAGERY SHOW FOG AND LOW CLOUDS
ARE CURRENTLY IN PLACE ACROSS SOUTH CENTRAL TEXAS. BASED ON RECENT
TRENDS AND THE LATEST HI-RES RUC MODEL...WE HAVE INCLUDED A
MENTION OF PATCHY...DENSE FOG ACROSS THE HILL COUNTRY AND SOUTHERN
EDWARDS PLATEAU. THE FOG IS EXPECTED TO DECREASE BY MID-MORNING AS
SOUTHERLY WINDS AND DAYTIME HEATING COMMENCE. AFTERNOON
TEMPERATURES WILL WARM TO ABOVE NORMAL LEVELS TODAY... WITH HIGHS
RANGING FROM THE UPPER 80S ALONG THE RIO GRANDE TO UPPER 70S ALONG
THE HIGHWAY 77 CORRIDOR. MOIST CONDITIONS REMAIN IN PLACE TONIGHT
AND WE/LL CONTINUE TO MENTION FOG AND DRIZZLE ACROSS MOST AREAS. A
PACIFIC COLD FRONT WILL MOVE THROUGH THE REGION ON THURSDAY. IN
ADVANCE OF THE FRONT...CAN/T RULE OUT SOME LIGHT MORNING SHOWERS
ALONG AND EAST OF THE I-35 CORRIDOR. WE/LL ALSO CONTINUE TO
MENTION A SLIGHT CHANCE FOR AFTERNOON THUNDERSTORMS EAST OF I-35
AS THE COLD FRONT WILL BE ACROSS THIS REGION DURING PEAK HEATING.
THE COLD FRONT WILL ALSO BRING AN INCREASE IN FIRE WEATHER
CONCERNS FOR AREAS ALONG AND WEST OF I-35. PLEASE SEE THE BELOW
FIRE WEATHER SECTION FOR MORE INFORMATION.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
WINDS WILL DECREASE THURSDAY NIGHT AS SKIES REMAIN MOSTLY CLEAR.
THIS ALONG WITH DRY AIR WILL ALLOW TEMPERATURES TO DROP INTO THE
LOWER 30S ACROSS THE HILL COUNTRY TO THE MID 40S COASTAL PLAINS.
SOUTHERLY FLOW IN THE LOW-LEVELS RESUMES ON FRIDAY AS ZONAL FLOW
ALOFT PERSISTS. A WARMING TREND IS EXPECTED SATURDAY AS THE LATEST
MEDIUM RANGE MODELS SHOW A COLD FRONT REMAINING NORTH OF THE
REGION. THERE IS SOME DISAGREEMENT AMONG THE MEDIUM RANGE MODELS
WITH REGARDS TO THE SOUTHWARD PROGRESS OF THE COLD FRONT ON
SUNDAY. FOR NOW...WILL SHOW SOME SLIGHTLY COOLER TEMPERATURES
NORTH OF I-10...WITH LITTLE CHANGE ELSEWHERE. THE FLOW ALOFT OVER
THE WESTERN U.S. WILL AMPLIFY EARLY NEXT WEEK...BUT DOES NOT
CHANGE SIGNIFICANTLY ACROSS THE SOUTHERN PLAINS. THIS PATTERN DOES
FAVOR PERIODIC COLD FRONTS MOVING INTO THE REGION AND WE/LL SHOW
SOME NEAR TO BELOW NORMAL TEMPERATURES ON TUESDAY. SOME LIGHT
SHOWERS ARE POSSIBLE EARLY NEXT WEEK...BUT OVERALL AMOUNTS AND
PRECIPITATION CHANCES WILL REMAIN LOW.
FIRE WEATHER...
CRITICAL TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE LIKELY FOR
AREAS MAINLY ALONG AND WEST OF THE I-35 CORRIDOR THURSDAY
AFTERNOON IN THE WAKE OF A PACIFIC COLD FRONT. RELATIVE HUMIDITIES
WILL DROP INTO THE TEENS WITH NORTH WINDS OF 15 TO 25 MPH AND
GUSTY FOLLOWING THE FRONTAL PASSAGE. ELEVATED FIRE WEATHER
CONDITIONS ARE POSSIBLE FRIDAY AFTERNOON MAINLY ALONG AND WEST OF
THE I-35 CORRIDOR AS RELATIVE HUMIDITIES AGAIN FALL INTO THE
TEENS WITH SOUTHERLY WINDS OF 10 TO 15 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 81 64 81 43 72 / - - 20 - -
AUSTIN BERGSTROM INTL AIRPORT 79 61 81 36 71 / - - 20 - -
NEW BRAUNFELS MUNI AIRPORT 80 61 83 39 73 / - - 20 - -
BURNET MUNI AIRPORT 78 60 76 37 69 / - - 20 - -
DEL RIO INTL AIRPORT 88 58 86 43 74 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 62 78 38 69 / - - 20 - -
HONDO MUNI AIRPORT 85 59 86 40 75 / - - 10 0 -
SAN MARCOS MUNI AIRPORT 79 62 81 39 71 / - - 20 - -
LA GRANGE - FAYETTE REGIONAL 78 64 79 42 69 / - 10 20 10 -
SAN ANTONIO INTL AIRPORT 82 63 85 44 74 / - - 10 - -
STINSON MUNI AIRPORT 82 62 86 43 73 / - - 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING
FOR THE FOLLOWING COUNTIES: BANDERA...BASTROP...BEXAR...BLANCO...
BURNET...CALDWELL...COMAL...DIMMIT...EDWARDS...FRIO...GILLESPIE...
GUADALUPE...HAYS...KENDALL...KERR...KINNEY...LLANO...MAVERICK...
MEDINA...REAL...TRAVIS...UVALDE...VAL VERDE...WILLIAMSON...ZAVALA.
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: ATASCOSA...BANDERA...BEXAR...BLANCO...COMAL...DIMMIT...
EDWARDS...FRIO...GILLESPIE...KENDALL...KERR...KINNEY...LLANO...
MAVERICK...MEDINA...REAL...UVALDE...VAL VERDE...ZAVALA.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...24
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
532 AM CST WED FEB 19 2014
.AVIATION...
FOG AND LOW CLOUDS WILL COVER THE AREA THIS MORNING. VIS LOOKS TO
BE THE DRIVING FACTOR THIS MORNING. LIFR TO VLIFR VIS IS LIKELY AT
THE AUSTIN AND SAN ANTONIO TERMINALS THROUGH LATE MORNING. DRT
WILL SEE VIS DOWN TO IFR. THERE IS A CHANCE OF DRIZZLE. VIS WILL IMPROVE
THIS AFTERNOON AND CIGS WILL LIFT TO LOW VFR. WINDS WILL PICK UP
TO 10 TO 15 KTS DURING THE AFTERNOON AND STAY UP THROUGH THE
EVENING. STRONGER WINDS SHOULD KEEP VIS BETTER THURSDAY
MORNING...BUT STILL EXPECTING MVFR VIS OVERNIGHT WITH IFR CIGS.
&&
.PREV DISCUSSION... /ISSUED 354 AM CST WED FEB 19 2014/
SHORT TERM (TODAY THROUGH THURSDAY)...
SURFACE OBSERVATIONS AND SATELLITE IMAGERY SHOW FOG AND LOW CLOUDS
ARE CURRENTLY IN PLACE ACROSS SOUTH CENTRAL TEXAS. BASED ON RECENT
TRENDS AND THE LATEST HI-RES RUC MODEL...WE HAVE INCLUDED A
MENTION OF PATCHY...DENSE FOG ACROSS THE HILL COUNTRY AND SOUTHERN
EDWARDS PLATEAU. THE FOG IS EXPECTED TO DECREASE BY MID-MORNING AS
SOUTHERLY WINDS AND DAYTIME HEATING COMMENCE. AFTERNOON
TEMPERATURES WILL WARM TO ABOVE NORMAL LEVELS TODAY... WITH HIGHS
RANGING FROM THE UPPER 80S ALONG THE RIO GRANDE TO UPPER 70S ALONG
THE HIGHWAY 77 CORRIDOR. MOIST CONDITIONS REMAIN IN PLACE TONIGHT
AND WE/LL CONTINUE TO MENTION FOG AND DRIZZLE ACROSS MOST AREAS. A
PACIFIC COLD FRONT WILL MOVE THROUGH THE REGION ON THURSDAY. IN
ADVANCE OF THE FRONT...CAN/T RULE OUT SOME LIGHT MORNING SHOWERS
ALONG AND EAST OF THE I-35 CORRIDOR. WE/LL ALSO CONTINUE TO
MENTION A SLIGHT CHANCE FOR AFTERNOON THUNDERSTORMS EAST OF I-35
AS THE COLD FRONT WILL BE ACROSS THIS REGION DURING PEAK HEATING.
THE COLD FRONT WILL ALSO BRING AN INCREASE IN FIRE WEATHER
CONCERNS FOR AREAS ALONG AND WEST OF I-35. PLEASE SEE THE BELOW
FIRE WEATHER SECTION FOR MORE INFORMATION.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
WINDS WILL DECREASE THURSDAY NIGHT AS SKIES REMAIN MOSTLY CLEAR.
THIS ALONG WITH DRY AIR WILL ALLOW TEMPERATURES TO DROP INTO THE
LOWER 30S ACROSS THE HILL COUNTRY TO THE MID 40S COASTAL PLAINS.
SOUTHERLY FLOW IN THE LOW-LEVELS RESUMES ON FRIDAY AS ZONAL FLOW
ALOFT PERSISTS. A WARMING TREND IS EXPECTED SATURDAY AS THE LATEST
MEDIUM RANGE MODELS SHOW A COLD FRONT REMAINING NORTH OF THE
REGION. THERE IS SOME DISAGREEMENT AMONG THE MEDIUM RANGE MODELS
WITH REGARDS TO THE SOUTHWARD PROGRESS OF THE COLD FRONT ON
SUNDAY. FOR NOW...WILL SHOW SOME SLIGHTLY COOLER TEMPERATURES
NORTH OF I-10...WITH LITTLE CHANGE ELSEWHERE. THE FLOW ALOFT OVER
THE WESTERN U.S. WILL AMPLIFY EARLY NEXT WEEK...BUT DOES NOT
CHANGE SIGNIFICANTLY ACROSS THE SOUTHERN PLAINS. THIS PATTERN DOES
FAVOR PERIODIC COLD FRONTS MOVING INTO THE REGION AND WE/LL SHOW
SOME NEAR TO BELOW NORMAL TEMPERATURES ON TUESDAY. SOME LIGHT
SHOWERS ARE POSSIBLE EARLY NEXT WEEK...BUT OVERALL AMOUNTS AND
PRECIPITATION CHANCES WILL REMAIN LOW.
FIRE WEATHER...
CRITICAL TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE LIKELY FOR
AREAS MAINLY ALONG AND WEST OF THE I-35 CORRIDOR THURSDAY
AFTERNOON IN THE WAKE OF A PACIFIC COLD FRONT. RELATIVE HUMIDITIES
WILL DROP INTO THE TEENS WITH NORTH WINDS OF 15 TO 25 MPH AND
GUSTY FOLLOWING THE FRONTAL PASSAGE. ELEVATED FIRE WEATHER
CONDITIONS ARE POSSIBLE FRIDAY AFTERNOON MAINLY ALONG AND WEST OF
THE I-35 CORRIDOR AS RELATIVE HUMIDITIES AGAIN FALL INTO THE
TEENS WITH SOUTHERLY WINDS OF 10 TO 15 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 81 64 81 43 72 / - - 20 - -
AUSTIN BERGSTROM INTL AIRPORT 79 61 81 36 71 / - - 20 - -
NEW BRAUNFELS MUNI AIRPORT 80 61 83 39 73 / - - 20 - -
BURNET MUNI AIRPORT 78 60 76 37 69 / - - 20 - -
DEL RIO INTL AIRPORT 88 58 86 43 74 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 62 78 38 69 / - - 20 - -
HONDO MUNI AIRPORT 85 59 86 40 75 / - - 10 0 -
SAN MARCOS MUNI AIRPORT 79 62 81 39 71 / - - 20 - -
LA GRANGE - FAYETTE REGIONAL 78 64 79 42 69 / - 10 20 10 -
SAN ANTONIO INTL AIRPORT 82 63 85 44 74 / - - 10 - -
STINSON MUNI AIRPORT 82 62 86 43 73 / - - 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING
FOR THE FOLLOWING COUNTIES: BANDERA...BASTROP...BEXAR...BLANCO...
BURNET...CALDWELL...COMAL...DIMMIT...EDWARDS...FRIO...GILLESPIE...
GUADALUPE...HAYS...KENDALL...KERR...KINNEY...LLANO...MAVERICK...
MEDINA...REAL...TRAVIS...UVALDE...VAL VERDE...WILLIAMSON...ZAVALA.
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: ATASCOSA...BANDERA...BEXAR...BLANCO...COMAL...DIMMIT...
EDWARDS...FRIO...GILLESPIE...KENDALL...KERR...KINNEY...LLANO...
MAVERICK...MEDINA...REAL...UVALDE...VAL VERDE...ZAVALA.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...24
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
354 AM CST WED FEB 19 2014
.SHORT TERM (TODAY THROUGH THURSDAY)...
SURFACE OBSERVATIONS AND SATELLITE IMAGERY SHOW FOG AND LOW CLOUDS
ARE CURRENTLY IN PLACE ACROSS SOUTH CENTRAL TEXAS. BASED ON RECENT
TRENDS AND THE LATEST HI-RES RUC MODEL...WE HAVE INCLUDED A
MENTION OF PATCHY...DENSE FOG ACROSS THE HILL COUNTRY AND SOUTHERN
EDWARDS PLATEAU. THE FOG IS EXPECTED TO DECREASE BY MID-MORNING AS
SOUTHERLY WINDS AND DAYTIME HEATING COMMENCE. AFTERNOON
TEMPERATURES WILL WARM TO ABOVE NORMAL LEVELS TODAY... WITH HIGHS
RANGING FROM THE UPPER 80S ALONG THE RIO GRANDE TO UPPER 70S ALONG
THE HIGHWAY 77 CORRIDOR. MOIST CONDITIONS REMAIN IN PLACE TONIGHT
AND WE/LL CONTINUE TO MENTION FOG AND DRIZZLE ACROSS MOST AREAS. A
PACIFIC COLD FRONT WILL MOVE THROUGH THE REGION ON THURSDAY. IN
ADVANCE OF THE FRONT...CAN/T RULE OUT SOME LIGHT MORNING SHOWERS
ALONG AND EAST OF THE I-35 CORRIDOR. WE/LL ALSO CONTINUE TO
MENTION A SLIGHT CHANCE FOR AFTERNOON THUNDERSTORMS EAST OF I-35
AS THE COLD FRONT WILL BE ACROSS THIS REGION DURING PEAK HEATING.
THE COLD FRONT WILL ALSO BRING AN INCREASE IN FIRE WEATHER
CONCERNS FOR AREAS ALONG AND WEST OF I-35. PLEASE SEE THE BELOW
FIRE WEATHER SECTION FOR MORE INFORMATION.
&&
.LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
WINDS WILL DECREASE THURSDAY NIGHT AS SKIES REMAIN MOSTLY CLEAR.
THIS ALONG WITH DRY AIR WILL ALLOW TEMPERATURES TO DROP INTO THE
LOWER 30S ACROSS THE HILL COUNTRY TO THE MID 40S COASTAL PLAINS.
SOUTHERLY FLOW IN THE LOW-LEVELS RESUMES ON FRIDAY AS ZONAL FLOW
ALOFT PERSISTS. A WARMING TREND IS EXPECTED SATURDAY AS THE LATEST
MEDIUM RANGE MODELS SHOW A COLD FRONT REMAINING NORTH OF THE
REGION. THERE IS SOME DISAGREEMENT AMONG THE MEDIUM RANGE MODELS
WITH REGARDS TO THE SOUTHWARD PROGRESS OF THE COLD FRONT ON
SUNDAY. FOR NOW...WILL SHOW SOME SLIGHTLY COOLER TEMPERATURES
NORTH OF I-10...WITH LITTLE CHANGE ELSEWHERE. THE FLOW ALOFT OVER
THE WESTERN U.S. WILL AMPLIFY EARLY NEXT WEEK...BUT DOES NOT
CHANGE SIGNIFICANTLY ACROSS THE SOUTHERN PLAINS. THIS PATTERN DOES
FAVOR PERIODIC COLD FRONTS MOVING INTO THE REGION AND WE/LL SHOW
SOME NEAR TO BELOW NORMAL TEMPERATURES ON TUESDAY. SOME LIGHT
SHOWERS ARE POSSIBLE EARLY NEXT WEEK...BUT OVERALL AMOUNTS AND
PRECIPITATION CHANCES WILL REMAIN LOW.
&&
.FIRE WEATHER...
CRITICAL TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE LIKELY FOR
AREAS MAINLY ALONG AND WEST OF THE I-35 CORRIDOR THURSDAY
AFTERNOON IN THE WAKE OF A PACIFIC COLD FRONT. RELATIVE HUMIDITIES
WILL DROP INTO THE TEENS WITH NORTH WINDS OF 15 TO 25 MPH AND
GUSTY FOLLOWING THE FRONTAL PASSAGE. ELEVATED FIRE WEATHER
CONDITIONS ARE POSSIBLE FRIDAY AFTERNOON MAINLY ALONG AND WEST OF
THE I-35 CORRIDOR AS RELATIVE HUMIDITIES AGAIN FALL INTO THE
TEENS WITH SOUTHERLY WINDS OF 10 TO 15 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 81 64 81 43 72 / - - 20 - -
AUSTIN BERGSTROM INTL AIRPORT 79 61 81 36 71 / - - 20 - -
NEW BRAUNFELS MUNI AIRPORT 80 61 83 39 73 / - - 20 - -
BURNET MUNI AIRPORT 78 60 76 37 69 / - - 20 - -
DEL RIO INTL AIRPORT 88 58 86 43 74 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 62 78 38 69 / - - 20 - -
HONDO MUNI AIRPORT 85 59 86 40 75 / - - 10 0 -
SAN MARCOS MUNI AIRPORT 79 62 81 39 71 / - - 20 - -
LA GRANGE - FAYETTE REGIONAL 78 64 79 42 69 / - 10 20 10 -
SAN ANTONIO INTL AIRPORT 82 63 85 44 74 / - - 10 - -
STINSON MUNI AIRPORT 82 62 86 43 73 / - - 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING
FOR THE FOLLOWING COUNTIES: BANDERA...BASTROP...BEXAR...BLANCO...
BURNET...CALDWELL...COMAL...DIMMIT...EDWARDS...FRIO...GILLESPIE...
GUADALUPE...HAYS...KENDALL...KERR...KINNEY...LLANO...MAVERICK...
MEDINA...REAL...TRAVIS...UVALDE...VAL VERDE...WILLIAMSON...ZAVALA.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...24
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1244 PM EST WED FEB 19 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE AREA THIS AFTERNOON AND INTO
THURSDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE AREA EARLY
FRIDAY WITH HEAVY SHOWERS...GUSTY WINDS...AND EVEN A FEW
THUNDERSTORMS ONCE AGAIN. SUCCESSIVELY COLDER TEMPERATURES ARE
EXPECTED FOR THE WEEKEND INTO NEXT WEEK...WITH AN INCREASING
THREAT FOR WINTER PRECIPITATION NEXT WEEK AND MUCH BELOW NORMAL
TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM EST WEDNESDAY...
A WEAK SURFACE FRONT IS APPROACHING WESTERN SLOPES OF SE WV EARLY
THIS AFTERNOON. THIS IS BEING PICKED UP BY HRRR THAN ANY OTHER
MODEL. I HAVE INCREASED POPS ALONG WESTERN SLOPES TO 30-40
PERCENT...THEN DECREASE CHANCES AND AREAL COVERAGE THROUGH THE
REMAINDER OF THE AFTERNOON. WINDS MAY ALSO BE BREEZY AND GUSTY
THIS AFTERNOON WITH PRESSURE RISES BEHIND THE FRONT.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
AS OF 400 AM EST WEDNESDAY...
EASTERLY COMPONENT STRENGTHENING IN RESPONSE TO AN AMPLIFYING
UPPER PATTERN...WILL KEEP TEMPS COOLER THAN WEDNESDAY AT MANY
LOCATIONS...ESPECIALLY ALONG THE BLUE RIDGE. ALSO PATCHY
DRIZZLE/SHOWERS WILL DEVELOP WITH THE UPSLOPE FLOW WELL AHEAD OF
THE FRONT THURSDAY AFTERNOON. STIFF BREEZE AND CLOUDS THURSDAY
NIGHT MAY KEEP SOME OF THE WARMER SPOTS NEAR THE MID 50S ALL
NIGHT. SHOWERS ASSOCIATED WITH THE FRONT SHOULD BREAK OUT AFTER
MIDNIGHT...WITH HEAVY RAIN AT TIMES THROUGH THE BLF/JFZ CORRIDOR.
MODELS GIVING A WIDESPREAD HALF INCH OF RAIN ACROSS THE
REGION...BUT THERE WILL BE SOME UPSLOPE ENHANCEMENT ALONG THE BLUE
RIDGE. THINKING THAT MOST OF THE SNOWCOVER WILL BE GONE AT THIS
POINT TO PRECLUDE WATER PROBLEMS. NOT MUCH INSTABILITY BUT THERE
REMAINS A SLT CHC OF THUNDER MAINLY ACROSS EXTREME SW VA AND THEN
THE VA/NC PIEDMONT IN THE AFTERNOON. SPC HAS PUT ROUGHLY THE AREA
EAST OF THE BLUE RIDGE INTO A SLT RISK ANTICIPATING A HIGH SHEAR
LOW CAPE SETUP THURSDAY LATE MORNING. QUITE POSSIBLE THAT THE
STRONGEST CELLS DEVELOP SOUTH OF OUR REGION...WHERE CONDITIONS ARE
MORE FAVORABLE...THEN RACE NNE ALONG THE BOUNDARY OR JUST AHEAD OF
IT INTO THE SOUTHSIDE. AIRMASS BEHIND THE FRONT IS COOLER...BUT
NOT WHAT ONE WOULD EXPECT IN FEBRUARY...AS BREEZY DOWNSLOPING
WINDS WILL PUSH MAX T ACROSS 60F AGAIN AT THE WARMEST SITES
SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 330 PM EST MONDAY...
HIGH PRESSURE WILL BUILD INTO THE REGION FRIDAY NIGHT IN THE WAKE OF
A DEPARTING COLD FRONT. DESPITE THE FRONTAL PASSAGE...AIR MOVING IN
FROM THE WEST WILL ONLY BE SLIGHTLY COOLER...AND EXPECT FRIDAY NIGHT
LOWS TO HOLD IN THE UPPER 20S TO THE LOW 30S...WHILE SATURDAY
AFTERNOON HIGHS REACH INTO THE 50S FOR MOST LOCATIONS...PERHAPS
TOUCHING 60 IN SOUTHSIDE VIRGINIA.
TEMPERATURES REMAIN RELATIVELY MILD SATURDAY NIGHT AS WINDS SHIFT
SOUTHWESTERLY AGAIN AHEAD OF OUR NEXT COLD FRONT...THIS ONE A
CLIPPER APPROACHING FROM THE NORTHWEST. AS WE HAVE SEEN SEVERAL
TIMES THIS WINTER...THIS CLIPPER WILL BRING UPSLOPE SNOW SHOWERS TO
THE MOUNTAINS...ESPECIALLY SOUTHEAST WEST VIRGINIA...WITH UP TO AN
INCH OF NEW SNOW POSSIBLY IN WESTERN GREENBRIER COUNTY. SNOW SHOWERS
WILL TAPER OFF SUNDAY MORNING AS CANADIAN HIGH PRESSURE BUILDS IN
FROM THE WEST TO CONTROL THE WEATHER PATTERN THROUGH MONDAY EVENING.
TEMPERATURES FOR SUNDAY NIGHT THROUGH MONDAY NIGHT WILL BE NEAR
SEASONAL NORMALS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 633 AM EST WEDNESDAY...
A WEAK COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA THIS
AFTERNOON. THERE ARE A FEW SHOWERS COMING ACROSS EASTERN KENTUCKY
THAT COULD IMPACT LEWISBURG (LWB) TO BLUEFIELD (BLF) TO MOUNT
AIRY (MWK) AND POINTS SOUTHWEST THROUGH THE AFTERNOON. VAD WIND
PROFILES HAS WEST WINDS ALOFT...THEREFORE SHOWERS MAY NOT SURVIVE
MOVING EAST ACROSS THE MOUNTAIN EMPIRE. THIS WEST WIND AND
MOISTURE WILL LIKLEY BRING IFR-MVFR CIELINGS ALONG WESTERN SLOPES
INTO THIS EVENING. PRESSURE RISES BEHIND THE FRONT WILL ALSO BRING
BREEZY AND GUSTY CONDITIONS TO THE AREA INTO EARLY THIS
EVENING...THEN DECOUPLE AS HIGH PRESSURE TRACKS OVER THE REGION.
HIGH PRESSURE AND CLEAR SKIES WILL WIN OUT THROUGH MOST OF THE
OVERNIGHT FOR ALL TAF SITES. TOWARDS SUNRISE...A WARM FRONT WILL
OVERRUN LINGERING SURFACE RIDGE TO INCREASE CLOUDS FROM THE
SOUTHWEST TO NORTHEAST. THROUGH THE DAY...CEILING COULD LOWER TO
MVFR ALONG AND EAST OF THE BLUE RIDGE. BY THURSDAY EVENING...LIGHT
RAIN/DRIZZLE/FOG LIKELY TO FORM AND REMAIN IN THE AREA UNTIL A
STRONGER FRONT PUSHES OVER THE REGION FRIDAY MORNING. EASTERLY
DOWNSLOPE FLOW WILL KEEP THE WEST (BLF-LWB) DRY WITH CIELINGS
REMAINING VFR UNTIL THE STRONGER FRONT APPORAHCES THE AREA.
A STRONG COLD FRONT WILL CROSS THE REGION LATE THURSDAY NIGHT INTO
EARLY FRIDAY MORNING. EXPECT A LINE OF GUSTY SHOWERS TO ACCOMPANY
THE FRONT...AND WINDS TO SHIFT NORTHWEST BEHIND IT BY MIDDAY FRIDAY.
A TREND TOWARD COLDER TEMPERATURES...BUT A SUSTAINED NORTHWEST
FLOW AND MAINLY VFR CONDITIONS WILL CONTINUE THROUGH THE WEEKEND.
HIGH PRESSURE...DRY AIR AND UNFAVORABLE WIND DIRECTION SHOULD
PRECLUDE UPSLOPE SNOW SHOWERS AT LWB AT THE END OF THE WEEKEND.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...RAB/RCS
SHORT TERM...KM
LONG TERM...NF
AVIATION...RCS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
557 PM CST THU FEB 20 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 325 PM CST THU FEB 20 2014
DANGEROUS WINTER STORM IMPACTING THE REGION THROUGH FRIDAY
MORNING.
STRONG LOW PRESSURE WAS MOVING INTO THE AREA THIS AFTERNOON
PRODUCING HEAVY SNOW...SLEET...RAIN...AND SCATTERED
THUNDERSTORMS. INTENSE SNOWFALL RATES ARE OCCURRING LEADING TO
DANGEROUS TRAVEL CONDITIONS. SEVERAL ACCIDENTS HAVE ALREADY BEEN
REPORTED. STRONG WEST/NORTHWEST WINDS ARE DEVELOPING ON THE BACK
EDGE OF THIS SYSTEM AND WILL MOVE INTO THE REGION THIS EVENING
INTO THE OVERNIGHT HOURS PRODUCING BLIZZARD CONDITIONS.
LOW PRESSURE WAS CENTERED OVER EAST CENTRAL IOWA AT 3 PM THIS
AFTERNOON AND WAS LIFTING NORTH INTO SOUTHWEST WISCONSIN AND
DEEPENING. THE BLIZZARD WARNING...WINTER STORM WARNING AND WINTER
WEATHER ADVISORIES ARE STILL ON TRACK. THERE IS A CONCERN THAT THE
WARM LAYER WILL ERODE FASTER THAN PREVIOUSLY THOUGHT OVER PORTIONS
OF WEST CENTRAL WISCONSIN. IF THIS IS THE CASE...THE WINTER STORM
WARNING MAY NEED TO BE EXPANDED EAST ANOTHER ROW OF COUNTIES. STILL
SOME UNCERTAINTY WITH THIS SCENARIO SO WILL MAINTAIN HEADLINES AND
CLOSELY MONITOR THE WARM LAYER THIS EVENING. THE STRONGEST WINDS
ARE EXPECTED TONIGHT AS THE LOW LIFTS INTO SOUTHWEST AND CENTRAL
WISCONSIN...WHEN WINDS WILL INCREASE TO 25 TO 35 MPH WITH GUSTS
AROUND 50 MPH LIKELY IN OPEN AREAS. THESE WINDS WILL CREATE
WHITEOUTS AND SIGNIFICANT DRIFTING SNOW. HAVE LEANED TOWARD HIGHER
SNOW TOTALS OVER SOUTHEAST MINNESOTA INTO WEST CENTRAL WISCONSIN
GIVEN THE CONVECTIVE NATURE OF THE SNOW. THINKING THE CORRIDOR
FROM AROUND ROCHESTER TO DODGE CENTER...NORTHEAST THROUGH FAR
NORTHWEST WABASHA COUNTY OVER TO THE EAU CLAIRE AREA SHOULD SEE
SNOWFALL ACCUMULATIONS IN THE 10 TO 15 INCH RANGE. LOCATIONS OVER
EXTREME NORTHEAST IOWA INTO FAR SOUTHWEST AND CENTRAL WISCONSIN
WILL BE IN THE WARMER AIR WITH WARM LAYER TEMPERATURES HOVERING
IN THE 4 TO 5 C LATE THIS AFTERNOON THEN FINALLY COOLING BELOW
FREEZING EARLY THIS EVENING WITH PRECIPITATION SWITCHING OVER TO
ALL SNOW. THE SNOW WILL FINALLY TAPER OFF LATE TONIGHT INTO FRIDAY
MORNING AS THE LOW LIFTS NORTHEAST OVER EASTERN LAKE SUPERIOR.
HOWEVER...STRONG WEST WINDS AND LIGHT SNOW WILL CONTINUE TO
PRODUCE HAZARDOUS TRAVEL CONDITIONS SO WILL CONTINUE THE WINTER
WEATHER HEADLINES THROUGH 18Z FRIDAY.
THE LOW FINALLY LIFTS NORTHEAST OF THE REGION FRIDAY AFTERNOON BUT
A WEAK SHORTWAVE IS EXPECTED TO TRACK ACROSS WESTERN INTO CENTRAL
IOWA AND MAY PRODUCE SOME LIGHT SNOW OVER NORTHEAST IOWA.
CONFIDENCE IS LOW ON THE SNOW IMPACTING NORTHEAST IOWA GIVEN THE
TRACK OF THIS SYSTEM IS FURTHER SOUTHWEST...SO HAVE LEFT IT OUT OF
THE FORECAST AT THIS TIME.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 PM CST THU FEB 20 2014
HIGH PRESSURE BUILDS INTO THE REGION FOR FRIDAY NIGHT THROUGH
SATURDAY PROVIDING DRY AND QUIET WEATHER. LOOK FOR HIGH TEMPERATURES
TO RANGE FROM THE UPPER TEENS TO LOWER 20S...AND LOWS TO FALL IN THE
SINGLE DIGITS ABOVE TO SINGLE DIGITS BELOW ZERO.
SUNDAY NIGHT THROUGH THURSDAY...
THE MAIN FOCUS THROUGH NEXT WEEK IS WITH THE POTENTIAL OF SOME LIGHT
SNOW ON MONDAY FOLLOWED BY HOW COLD IT WILL BE THE REST OF THE WEEK.
SNOW IS POSSIBLE ON MONDAY...MAINLY ACROSS NORTHEAST
IOWA...SOUTHEAST MINNESOTA AND FAR SOUTHWEST WISCONSIN...AS A MID
LEVEL SHORT WAVE TROUGH DIVES DOWN INTO THE REGION. SNOW SHOULD
MAINLY BE ON THE LIGHT SIDE WITH ABOUT A TENTH OF AN INCH OF LIQUID
EQUIVALENT FORECAST. THIS WILL BE A FAIRLY QUICK MOVING SYSTEM THAT
SHOULD MAINLY BE THROUGH BY OVERNIGHT.
THIS SYSTEM WILL PULL DOWN AN INITIAL SURGE OF COLD AIR DOWN FROM
CANADA WITH ANOTHER SURGE COMING LATER IN THE WEEK. 850MB
TEMPERATURES DROP FROM -14C EARLY ON MONDAY DOWN TO -19C BY TUESDAY
NIGHT AND THEN INTO THE -20 TO -30C RANGE ON THURSDAY. THIS WILL
LEAD TO TEMPERATURES STAYING IN THE TEENS TO SINGLE DIGITS BELOW
ZERO FOR MUCH OF NEXT WEEK. THE COLDEST DAY LOOKS LIKE IT WILL BE
ON THURSDAY WHEN MORNING LOWS WILL BE IN THE TEENS BELOW ZERO WITH A
WIND CHILL ADVISORY LIKELY BEING NEEDED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 557 PM CST THU FEB 20 2014
THE AREA OF LOW PRESSURE WAS LOCATED NEAR KDBQ LATE THIS AFTERNOON
AND WILL CONTINUE TO MOVE NORTH/NORTHEAST TOWARD THE U.P. OF
MICHIGAN. THIS WILL EVENTUALLY PULL THE COLDER AIR EAST AND ALLOW
FOR A CHANGE OVER TO SNOW AT KLSE...BUT THIS MAY NOT HAPPEN UNTIL
MID EVENING. THE 20.22Z RAP INDICATES THAT ICE MAY NOT BE PRESENT
IN THE CLOUDS WHICH WILL SERVE TO KEEP THE PRECIPITATION TYPE AS
RAIN OR FREEZING RAIN/DRIZZLE UNTIL THE COLDER AIR AND ICE
ARRIVES. HAVE TRIED TO COVER THESE VARIATIONS IN THE PRECIPITATION
TYPE THROUGH ABOUT 04Z. BY THE TIME THIS SWITCH OVER OCCURS...THE
HEAVIEST OF THE PRECIPITATION MAY HAVE ALREADY MOVED BY KLSE SO
HAVE ONLY GONE WITH A SHORT PERIOD OF IFR VISIBILITIES BEFORE
COMING BACK UP TO MVFR. AT KRST...THE HEAVY SNOW IS EXPECTED TO
CONTINUE THROUGH THE MIDDLE OF THE EVENING BEFORE STARTING TO LIFT
TO THE NORTH. HOWEVER...AS IT DOES...EXPECT TO SEE THE WINDS START
TO INCREASE WITH GUSTS TO 40 KNOTS POSSIBLE. THIS WILL BE MORE
THAN ENOUGH TO PRODUCE BLOWING SNOW TO KEEP THE VISIBILITY BELOW A
MILE FOR MUCH OF THE NIGHT. NOT INCLUDING ANY BLOWING SNOW FOR
KLSE DESPITE GUSTS OF 35 KNOTS AS THE RAIN EARLY TODAY HAS
MOISTURE LOADED THE SNOW TOO MUCH TO ALLOW IT TO MOVE WITH NOT A
LOT OF FRESH SNOW EXPECTED. THE WINDS WILL SLOWLY DECREASE DURING
THE DAY FRIDAY BUT STILL REMAIN STRONG ENOUGH FOR THE BLOWING SNOW
TO CONTINUE WITH MVFR VISIBILITIES AT KRST FOR MUCH OF THE DAY
DESPITE THE CLOUDS CLEARING OUT DURING THE EARLY AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING UNTIL NOON CST FRIDAY FOR WIZ017-029-
032>034.
MN...BLIZZARD WARNING UNTIL NOON CST FRIDAY FOR MNZ079-086-087-094-
095.
WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR MNZ096.
WINTER STORM WARNING UNTIL NOON CST FRIDAY FOR MNZ088.
IA...BLIZZARD WARNING UNTIL NOON CST FRIDAY FOR IAZ008>010-018-019-
029.
WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR IAZ011-030.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP/HALBACH
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
328 PM CST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 328 PM CST WED FEB 19 2014
DANGEROUS WINTER STORM TO IMPACT THE AREA THURSDAY AFTERNOON INTO
THURSDAY NIGHT.
STRONG LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS TONIGHT AND
IS EXPECTED TO START TRACKING NORTHEAST TOWARD THE UPPER
MISSISSIPPI RIVER VALLEY. WARM AIR ADVECTION OVERSPREADS THE
REGION TONIGHT AHEAD OF THE DEVELOPING SYSTEM AND WILL LEAD TO A
WINTRY MIX OF FREEZING RAIN...SLEET AND SNOW. THE BULK OF THE
PRECIPITATION TONIGHT WILL OCCUR ALONG AND SOUTH OF THE INTERSTATE
90 CORRIDOR. LIGHT ICE ACCUMULATIONS OF AROUND 1/10 OF AN INCH ARE
POSSIBLE MAINLY OVER PORTIONS OF NORTHEAST IOWA INTO FAR
SOUTHWEST WISCONSIN. THIS LIGHT ICING WILL LEAD TO A SLICK
THURSDAY MORNING COMMUTE.
THE MAIN SYSTEM LIFTS INTO THE AREA THURSDAY AFTERNOON WITH
CONDITIONS RAPIDLY DETERIORATING DURING THE EARLY AFTERNOON HOURS.
LOOK FOR HEAVY SNOW TO OVERSPREAD THE REGION WITH SNOWFALL RATES
OF 1 TO 2 INCHES PER HOURS LIKELY. TRAVEL CONDITIONS WILL BECOME
DANGEROUS BY LATE THURSDAY AFTERNOON. AS THE CYCLONE LIFTS INTO
SOUTHERN WISCONSIN DURING THE LATE AFTERNOON AND EARLY EVENING
NORTHWEST WINDS WILL INCREASE TO 25 TO 35 MPH ON THE BACK SIDE OF
THE LOW...LEADING TO BLIZZARD CONDITIONS ACROSS OPEN AREAS. THERE
REMAINS SOME UNCERTAINTY ON SNOW ACCUMULATIONS OVER PORTIONS OF
CENTRAL WISCONSIN WHERE WARMER AIR WILL KEEP MORE OF A
RAIN/SLEET/SNOW MIX GOING INTO THE EARLY EVENING HOURS. DECIDED TO
INCLUDE GRANT COUNTY IN THE WINTER STORM WARNING WHERE AROUND 3.5
INCHES OF SNOW AND THE STRONG NORTHWEST WINDS WILL LEAD TO NEAR
BLIZZARD CONDITIONS AT TIMES. THE MORE SHELTERED LOCATIONS OVER
CENTRAL WISCONSIN ARE EXPECTED TO SEE SNOW AMOUNTS OF 1 TO 3
INCHES OF SNOW AND SLIGHTLY LIGHTER WIND SPEEDS. HAVE SIDED WITH
THE ECMWF/GFS FOR THE LOW TRACK TONIGHT. IF THE SYSTEM WOULD SLIDE
SLIGHTLY FURTHER EAST...RICHLAND...ADAMS...AND JUNEAU COUNTIES
WOULD LIKELY NEED TO BE UPGRADED TO A WINTER STORM WARNING.
FURTHER TO THE WEST...OVER MUCH OF NORTHEAST IOWA...SOUTHEAST
MINNESOTA...AND WEST CENTRAL INTO NORTH CENTRAL WISCONSIN...SNOW
ACCUMULATIONS OF 6 TO 10 INCHES ARE EXPECTED. ROADS WILL LIKELY
BECOME IMPASSABLE...ESPECIALLY ACROSS THE OPEN AREAS OF SOUTHEAST
MINNESOTA INTO NORTHEAST IOWA FROM THE DRIFTING SNOW.
ALSO...VISIBILITIES WILL BE REDUCED TO ZERO AT TIMES. THE LOW
FINALLY OCCLUDES AND LIFTS NORTH OVER LAKE SUPERIOR LATE THURSDAY
NIGHT INTO EARLY FRIDAY MORNING WITH SNOW TAPERING OFF.
HOWEVER...STRONG NORTHWEST WINDS WILL CONTINUE TO PRODUCE AREAS OF
BLOWING AND DRIFTING SNOW...IMPACTING THE FRIDAY MORNING COMMUTE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 328 PM CST WED FEB 19 2014
COOL HIGH PRESSURE BUILDS BACK INTO THE REGION LATE FRIDAY INTO
SATURDAY AND REMAINS OVER THE REGION THROUGH THE WEEKEND. PLAN ON
QUIET WEATHER WITH HIGHS IN THE TEENS TO LOWER 20S AND LOWS IN THE
SINGLE DIGITS ABOVE AND BELOW ZERO. THE NEXT CHANCE FOR SNOW MOVES
ACROSS THE AREA MONDAY INTO MONDAY NIGHT...BUT LATEST TRENDS
APPEAR THAT IT MAY TRACK JUST SOUTH OF THE FORECAST AREA. COLD
HIGH PRESSURE LOOKS TO MAKE A RETURN TUESDAY NIGHT WITH LOWS
FALLING INTO THE SINGLE DIGITS TO TEENS BELOW ZERO. EVEN COLDER
TEMPERATURES ARE POSSIBLE WEDNESDAY NIGHT WHEN LOWS COULD FALL
INTO THE TEENS BELOW ZERO ACROSS THE ENTIRE FORECAST AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY)
ISSUED AT 1152 AM CST WED FEB 19 2014
THE 19.12Z NAM APPEARS TO BE AN OUTLIER WHEN COMPARED TO THE OTHER
19.12Z MODELS. DUE THIS...DID NOT CONSIDER THE NAM WHEN MAKING THE
AVIATION FORECAST. EVEN WITH THIS MODEL OUT OF THE MIX...THERE
CONTINUES TO BE SOME QUESTIONS ON HOW FAR WEST WILL WARM AIR WILL
GET LATE THURSDAY MORNING AND AFTERNOON. THE GFS...GEM...AND
UKMET SUGGEST THAT THE WARM AIR WILL ADVANCE AS FAR WEST AS THE
MISSISSIPPI RIVER. THIS WILL AFFECT BOTH THE PRECIPITATION TYPE
AND SNOW AMOUNTS AT LA CROSSE. BUFKIT SOUNDINGS SUGGEST THAT THE
PRECIPITATION WILL START OUT AS SNOW IN LA CROSSE AROUND 20.10Z
AND THEN TRANSITION OVER TO RAIN BY 20.16Z. THERE WAS EVEN SOME
HINTS IN THE RAP THAT THERE MAY BE EVEN SOME FREEZING RAIN
OVERNIGHT. SINCE THIS WAS THE ONLY ONE SHOWING IT AT THAT
TIME...JUST WENT WITH SNOW LATE TONIGHT. MEANWHILE AT KRST THE
PRECIPITATION LOOKS LIKE IT WILL STAY MAINLY SNOW...BUT THERE MAY
BE A BRIEF PERIOD OF SLEET. SNOW TOTALS THROUGH NOON WILL BE
AROUND AN INCH...AND THEN A RAPID INCREASE DURING THE AFTERNOON
AND EARLY EVENING. HOURLY SNOW RATES OF 1 TO 2 INCHES AN HOUR
DURING THE LATE AFTERNOON AND EARLY EVENING. TOTAL SNOWFALL
RANGING FROM 6 TO 10 INCHES.
CEILINGS AND VISIBILITIES AT BOTH TAF SITES WILL QUICKLY BECOME
IFR ONCE THE PRECIPITATION BEGINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
WIZ041-042-053-054-061.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
WIZ017-029-032>034-041-042-053-054-061.
WINTER WEATHER ADVISORY FROM 3 AM THURSDAY TO 6 AM CST FRIDAY
FOR WIZ043-044-055.
MN...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
MNZ086>088-094>096.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ079-086-087-094-095.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ088-096.
IA...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
IAZ008>011-018-019-029-030.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ008>010-018-019-029.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ011-030.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1154 AM CST WED FEB 19 2014
.SHORT TERM...(TODAY THROUGH THROUGH THURSDAY)
ISSUED AT 414 AM CST WED FEB 19 2014
INCOMING MAJOR WINTER STORM IS MAIN FORECAST FOCUS.
CURRENT WATER VAPOR ANALYSIS HAS A TROUGH OF LOW PRESSURE PUSHING
EAST OF THE REGION. RADAR WAS SHOWING SOME RETURNS ACROSS SOUTHEAST
WI WITH THIS FEATURE. AT THE SURFACE...HIGH PRESSURE WAS MOVING INTO
THE REGION FROM THE PLAINS. UNDER MOSTLY CLEAR SKIES...TEMPERATURES
ACROSS THE AREA WERE IN THE 20S. OF BIGGER CONCERN ON WATER VAPOR
WAS A DEEPENING TROUGH COMING ONSHORE OFF THE WEST COAST. THIS WAS
PRODUCING SURFACE CYCLOGENESIS OVER THE INTERMOUNTAIN WEST. THIS
CYCLONE WILL BE OUR MAJOR WINTER STORM HEADING INTO
THURSDAY/THURSDAY NIGHT.
PRETTY DECENT DAY ON TAP FOR TODAY AS HIGH PRESSURE DRIFTS ACROSS
THE REGION AND WITH WEAK WARM AIR ADVECTION KICKING IN LATER THIS
AFTERNOON. SKIES EXPECTED TO START OFF MOSTLY SUNNY...THEN WILL SEE
AN INCREASE IN HIGH/MID CLOUDS THROUGH THE AFTERNOON IN RESPONSE TO
THE WARM AIR ADVECTION. OTHERWISE...LOOK FOR HIGHS TODAY IN THE MID-
UPPER 30S.
TONIGHT GETS A BIT MESSY AS A WEAKER LEAD/MID-LEVEL WAVE GET EJECTED
TOWARD THE UPPER MISSISSIPPI RIVER REGION AFTER MIDNIGHT AHEAD OF
THE MAIN TROUGH/STRONGER SURFACE CYCLOGENESIS OVER THE SOUTHERN
PLAINS. MODERATE ISENTROPIC UPGLIDE AND WEAK 700-300MB PV-ADVECTION
WILL BE ENOUGH TO BRING IN A WINTRY MIX OF SNOW/SLEET AND POSSIBLY
POCKETS OF FREEZING RAIN TOWARD MORNING...THEN LASTING INTO MID/LATE
MORNING. THIS IS OF COURSE BEFORE THE MAIN LOW THAT WILL BE
DEEPENING OVER THE CENTRAL PLAINS. THEN LOOK FOR THE MAIN LOW TO
DEEPEN QUICKLY AND MOVE NORTHEAST INTO NORTHWEST IL BY 18Z AND THEN
INTO SOUTHEAST WI BY LATE AFTERNOON. STRONG MID-LEVEL FRONTOGENESIS
NORTHWEST OF THE LOW WILL RAPIDLY COOL THE COLUMN BY LATER IN THE
MORNING/EARLY AFTERNOON FOR ALL SNOW ACROSS ALL BUT PORTIONS OF
NORTHEAST IA INTO FAR SOUTHWEST WI WHERE A WINTRY MIX MAY LINGER A
BIT LONGER INTO THURSDAY AFTERNOON. STRONGER FRONTOGENESIS AND
SLANTWISE CONVECTION/POCKETS OF THUNDERSNOW NORTHWEST OF THIS LOW
TRACK WILL LEAD TO RAPID SNOW ACCUMULATIONS ACROSS NORTHEAST
IA/SOUTHEAST MN...INTO SOUTHWEST/CENTRAL WI. CURRENT THINKING IS THE
HEAVIEST SNOWFALL AXIS WILL EXTEND FROM MEDFORD WI THROUGH WINONA MN
TO CHARLES CITY IA...WHERE 8-12 INCHES LOOKS LIKELY. LOOK FOR WEST
TO NORTHWEST WINDS TO KICK IN ON THE BACKSIDE OF THE LOW TOWARD NOON
AND THEN GET VERY STRONG BY LATE IN THE AFTERNOON GUSTING IN THE 40-
50 MPH RANGE WEST OF THE MISSISSIPPI RIVER DURING THE HEAVY SNOW
PERIOD. WHITEOUT CONDITIONS WILL LIKELY BE SEEN ACROSS THE MORE OPEN
AREAS OF SOUTHEAST MN AND NORTHEAST IA. FURTHER EAST STRONGER WINDS
WILL KICK IN MORE IN THE EVENING AS THE LOW CONTINUES TO PULL TOWARD
UPPER MI.
HEADLINES FOR THIS MAJOR STORM SYSTEM ARE SOMEWHAT COMPLICATED
//SEE BELOW IN THE WWA SECTION FOR DETAILS // DUE TO THE INITIAL
WINTRY MIX DURING THE MORNING...THEN TRANSITIONING INTO WINTER
STORM/BLIZZARD WARNING CRITERIA LATE MORNING INTOTHE AFTERNOON. WILL
BE STICKING WITH A WATCH ACROSS JUNEAU/ADAMS/RICHLAND/GRANT COUNTIES
DUE TO THE FACT THAT THESE COUNTIES WILL BE IN WARMER AIR LONGER AND
SNOW AMOUNTS STILL A BIT UNCERTAIN.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 414 AM CST WED FEB 19 2014
LOOK FOR THE SNOW TO SLOWLY TAPER OFF THROUGH THURSDAY NIGHT...BUT
STRONG/GUSTY NORTHWEST WINDS OF 35-45 MPH WILL CONTINUE...CAUSING
WIDESPREAD BLOWING AND DRIFTING OF THE SNOW.
NOT MUCH TIME WAS SPENT PAST THE TIME FRAME OF THIS MAJOR STORM
SYSTEM. BOTTOM LINE WILL BE COLDER NORTHWEST FLOW ACROSS THE AREA.
APPEARS TO BE A SHOT AT SOME LIGHT SNOW MON/MON NIGHT TIME FRAME
WITH A WEAK MID-LEVEL TROUGH. HIGHS START OFF IN THE 20S ON
FRIDAY...THEN LOOK TO BE IN THE TEENS THROUGH THE WEEKEND INTO EARLY
NEXT WEEK.
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY)
ISSUED AT 1152 AM CST WED FEB 19 2014
THE 19.12Z NAM APPEARS TO BE AN OUTLIER WHEN COMPARED TO THE OTHER
19.12Z MODELS. DUE THIS...DID NOT CONSIDER THE NAM WHEN MAKING THE
AVIATION FORECAST. EVEN WITH THIS MODEL OUT OF THE MIX...THERE
CONTINUES TO BE SOME QUESTIONS ON HOW FAR WEST WILL WARM AIR WILL
GET LATE THURSDAY MORNING AND AFTERNOON. THE GFS...GEM...AND
UKMET SUGGEST THAT THE WARM AIR WILL ADVANCE AS FAR WEST AS THE
MISSISSIPPI RIVER. THIS WILL AFFECT BOTH THE PRECIPITATION TYPE
AND SNOW AMOUNTS AT LA CROSSE. BUFKIT SOUNDINGS SUGGEST THAT THE
PRECIPITATION WILL START OUT AS SNOW IN LA CROSSE AROUND 20.10Z
AND THEN TRANSITION OVER TO RAIN BY 20.16Z. THERE WAS EVEN SOME
HINTS IN THE RAP THAT THERE MAY BE EVEN SOME FREEZING RAIN
OVERNIGHT. SINCE THIS WAS THE ONLY ONE SHOWING IT AT THAT
TIME...JUST WENT WITH SNOW LATE TONIGHT. MEANWHILE AT KRST THE
PRECIPITATION LOOKS LIKE IT WILL STAY MAINLY SNOW...BUT THERE MAY
BE A BRIEF PERIOD OF SLEET. SNOW TOTALS THROUGH NOON WILL BE
AROUND AN INCH...AND THEN A RAPID INCREASE DURING THE AFTERNOON
AND EARLY EVENING. HOURLY SNOW RATES OF 1 TO 2 INCHES AN HOUR
DURING THE LATE AFTERNOON AND EARLY EVENING. TOTAL SNOWFALL
RANGING FROM 6 TO 10 INCHES.
CEILINGS AND VISIBILITIES AT BOTH TAF SITES WILL QUICKLY BECOME
IFR ONCE THE PRECIPITATION BEGINS.
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
WIZ041>044-053>055-061.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
WIZ017-029-032>034-041-042-053-054.
WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR WIZ043-044-055-061.
MN...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
MNZ086>088-094>096.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ079-086-087-094-095.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ088-096.
IA...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
IAZ008>011-018-019-029-030.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ008>010-018-019-029.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ011-030.
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
351 AM CST WED FEB 19 2014
.UPDATE...
ISSUED AT 351 AM CST WED FEB 19 2014
PRELIMINARY HEADLINES BELOW. MAJOR AFD COMING AROUND 415 AM.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 321 PM CST TUE FEB 18 2014
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED SHORTWAVE TROUGHS OVER MANITOBA AND OVER EASTERN
SOUTH DAKOTA INTO NEBRASKA...RIDGING OVER THE NORTHERN
ROCKIES...AND A POTENT UPPER TROUGH JUST OFF THE BRITISH COLUMBIA
AND PACIFIC NORTHWEST COASTS. THIS POTENT UPPER TROUGH IS THE
CULPRIT FOR OUR THURSDAY STORM. DPVA AND PACIFIC MOISTURE AHEAD OF
THE TWO SHORTWAVE TROUGHS HAVE BEEN SPREADING MID AND HIGH CLOUDS
ACROSS THE FORECAST AREA TODAY. THESE CLOUDS HAVE LIMITED SOME
INSULATION...BUT SOUTHWESTERLY 925-850MB FLOW AHEAD OF A COLD
FRONT MOVING INTO THE FORECAST AREA HELPED BOOST TEMPERATURES INTO
THE 30S TO MID 40S THIS AFTERNOON. OVER WESTERN IOWA WHERE NO SNOW
EXISTS...READINGS ARE IN THE 50S TO LOW 60S. IN THE WAKE OF THE
COLD FRONT...READINGS ARE STILL IN THE 30S AND 40S...PARTIALLY DUE
TO A BIT MORE SUN AND DOWNSLOPING FLOW OFF THE NORTHERN ROCKIES.
THE QUIET BEFORE THE STORM PHRASE WORKS PERFECTLY FOR THE SHORT
TERM. 18.12Z MODEL GUIDANCE DEPICT THE RIDGING OVER THE NORTHERN
ROCKIES MARCHING EASTWARD TO ABOUT OVER THE FORECAST AREA BY 00Z
THU...PUSHED BY THE POTENT NORTHEAST PACIFIC NORTHWEST TROUGH
PLOWING INTO THE ROCKIES. ON THE EAST SIDE OF THE UPPER RIDGE AXIS
THERE IS A WEAK SHORTWAVE AT 500MB SUGGESTED TO DROP SOUTHEAST
THROUGH THE FORECAST AREA LATE TONIGHT...BUT THIS FEATURE WILL COME
THROUGH DRY WITH BASICALLY NO CLOUD.
ONLY REAL ISSUE TO CONTEND WITH TONIGHT IS IF ANY FOG CAN FORM
RESULTING FROM MELTING SNOW. ALL MODELS KEEP A DECENT PRESSURE
GRADIENT IN PLACE TONIGHT WITH A SURFACE RIDGE AXIS ONLY REACHING
WESTERN MN BY 12Z WED. 925MB WINDS STAY UP 20-30 KT FOR MUCH OF THE
NIGHT IN THE WAKE OF THE COLD FRONTAL PASSAGE THIS EVENING.
THUS...THINK ANY FOG WOULD BE LIMITED TO PERHAPS THE TYPICAL COLD
SPOTS AND SOME SMALL VALLEYS.
PLENTY OF SUN LOOKS ON TAP FOR WEDNESDAY...OUTSIDE OF SOME CLOUDS
INCREASING LATE AS THE RIDGE AXIS APPROACHES. 925MB TEMPS IN THE 0-
2C RANGE AT 18Z WED SUPPORTS HIGHS IN THE 30S TO A COUPLE
40S...WARMEST IN SOUTHWEST WI.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 321 PM CST TUE FEB 18 2014
...WINTER STORM FOR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
MANY FACETS OF THE STORM TO TALK ABOUT...
MODEL ANALYSIS...18.12Z GUIDANCE CONTINUES TO FOLLOW THE PAST COUPLE
OF CYCLES...PHASING TROUGHING OVER THE ROCKIES ON TOP OF THE
FORECAST AREA THURSDAY. THE PHASED UPPER TROUGH ALSO BECOMES
NEGATIVELY TITLED AS IT LIFTS THROUGH THE FORECAST AREA THURSDAY
EVENING. OVERALL...THE SPREAD IN GUIDANCE FROM 500MB TO THE SURFACE
IS FAIRLY LOW CONSIDERING THIS IS A PHASING TROUGH AND STILL ISNT
ONSHORE YET. THEREFORE...CONFIDENCE IS INCREASING THAT A HIGH IMPACT
WINTER STORM WILL AFFECT THE FORECAST AREA.
WINDS...MOST OF THE GUIDANCE IS IN AGREEMENT THAT AS THE PHASING
TAKES PLACE OF THE UPPER TROUGH...THE SURFACE LOW IS GOING TO
UNDERGO BOMBOGENESIS...DROPPING FROM A PRESSURE OF 995MB IN EASTERN
KS AT 12Z THU TO AROUND 970MB OVER LAKE SUPERIOR AT 12Z FRI. TO
HANDLE THIS PRESSURE DROP AND THE COLD AIR THAT GETS PULLED
IN...925MB WINDS INCREASE OUT OF THE WEST-NORTHWEST AT 30-50 KT ON
THE BACK SIDE OF THE STORM FOR THURSDAY EVENING. THE STRONGEST CORE
TRACKS ACROSS SOUTHEAST MN AND NORTHEAST IOWA...THE FAVORABLE
BLIZZARD AREA.
PRECIPITATION...THERE IS SOME UNCERTAINTY ON HOW QUICK PRECIPITATION
DEVELOPS. GFS/NAM/ECMWF SOUNDINGS DEPICT A DECENT DRY LAYER BETWEEN
900-700MB WEDNESDAY NIGHT...WITH MUCH OF THE LIFT FROM WARM
ADVECTION IN THAT LAYER VERSUS IN THE MID/HIGH CLOUDS ABOVE IT.
PRECIPITATION SHOULD STAND A MUCH BETTER CHANCE MOVING IN
THURSDAY...LIKELY SOUTH TO NORTH...AS THE STORM SYSTEM MOVES INTO
SOUTHERN WI. DURING THE AFTERNOON...FRONTOGENESIS IN THE MID/UPPER
LEVELS REALLY INTENSIFIES WITH THE APPROACH OF THE UPPER TROUGH...
WHICH SHOULD DEVELOP A STRONG AND HEAVY PRECIPITATING COLD CONVEYOR
BELT. PRECIPITABLE WATER PROGGED BETWEEN 0.5-0.75 INCHES OR 200-250
PERCENT OF NORMAL SUGGESTS PLENTY OF MOISTURE AVAILABLE FOR THE
FORCING TO PRODUCE FAIRLY HEAVY QPF. CROSS-SECTIONS EVEN SHOW A
LARGE AREA OF NEGATIVE EPV AND SOME WEAK CAPE IN THE AFTERNOON...
SUGGESTING THUNDER COULD OCCUR. WILL SEE IF THIS TRENDS HOLDS WITH
LATER MODELS. COLD CONVEYOR BELT WILL GRADUALLY LIFT INTO THE U.P.
OF MI THU NIGHT...GRADUALLY ENDING PRECIPITATION SOUTHWEST TO
NORTHEAST.
PRECIPITATION TYPE...A DRY WARM LAYER ALOFT SHOULD RESIDE OVER THE
FORECAST AREA WEDNESDAY NIGHT. AS THE PRECIPITATION SPREADS IN LATE
WEDNESDAY NIGHT/THURSDAY MORNING...THAT COULD FALL AS EITHER
SLEET...FREEZING RAIN OR RAIN UNTIL EVAPORATIVE COOLING SWITCHES IT
OVER TO SNOW. THE AFTERNOON IS TRICKY AND COMPLETELY DEPENDS ON THE
850MB LOW TRACK. AHEAD OF THE 850MB LOW...A WARM LAYER ALOFT AND AT
THE SURFACE WILL ADVECT NORTH...RESULTING IN A MIX OR COMPLETELY
SWITCHOVER TO RAIN. RIGHT NOW THIS SEEMS MOST PROBABLE TO OCCUR IN
FAR SOUTHEAST SECTIONS OF THE FORECAST AREA FROM 15-21Z THU. IF THE
LOW TRACKS FARTHER NORTHWEST LIKE THE 18.12Z UKMET...THEN RAIN COULD
FALL EVEN AT LA CROSSE. HOWEVER...THE UKMET IS A NORTHWEST OUTLIER.
SNOW AMOUNTS/ICE ACCUMULATION...ANY ICE ACCUMULATION LOOKS TO BE
LATE WEDNESDAY NIGHT FROM THE INITIAL WARM LAYER. EVEN SNOW AMOUNTS
REALLY DO NOT START TO PICK UP UNTIL LATE THURSDAY MORNING WHEN
HEAVIER PRECIPITATION BEGINS TO DEVELOP. DURING THURSDAY AFTERNOON
AND EVENING...1 TO 2 INCH PER HOUR RATES ARE POSSIBLE...ESPECIALLY
IF CONVECTION FORMS. PRESENTLY DEPICT 2 TO 10 INCHES FOR
TOTALS...HIGHEST IN NORTH CENTRAL WI WHERE THE LONGEST DURATION OF
SNOW IS EXPECTED. IMPORTANT...THESE AMOUNTS ARE SUBJECT TO
CHANGE...AS EVEN THE NEW 18.18Z NAM SUGGESTS OF A FOOT IN SOUTHEAST
MN.
...REST OF THE LONG TERM PERIOD...
AFTER THE WINTER STORM...THE WEATHER GETS QUIET. 18.12Z
ECMWF/CANADIAN/GFS AND ENSEMBLE DATA REMAIN CONSISTENT IN FORMING AN
OMEGA BLOCK FROM THE U.S. WEST COAST INTO ALASKA...RESULTING IN DEEP
TROUGHING OVER MUCH OF CANADA AND INTO THE UPPER MIDWEST. THIS
ALLOWS FOR A GRADUAL COOLING TREND FROM FRIDAY THROUGH NEXT
TUESDAY...AND ACCORDING TO THE CFS WOULD CONTINUE THROUGH THE REST
OF THE MONTH. WIND CHILLS THROUGH TUESDAY LOOK TO STAY JUST ABOVE
WIND CHILL ADVISORY CRITERIA...I.E. -20 F. DESPITE THE COOLING
TREND...THERE ARE NOT THAT MANY PRECIPITATING SYSTEMS TO DEAL WITH.
THERE ARE SOME HINTS OF A WEAK SHORTWAVE CROSSING THE SOUTHERN
PORTION OF THE FORECAST AREA FRIDAY NIGHT WITH SOME LIGHT SNOW.
LOOKING OUT TO MONDAY AND MONDAY NIGHT OUR SOUTHERN FORECAST AREA
COULD ALSO GET CLIPPED BY A MID LEVEL FRONTOGENESIS BAND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1113 PM CST TUE FEB 18 2014
BAND OF CLOUDS ASSOCIATED WITH A SHORT WAVE TROUGH MOVING ACROSS
THE REGION HAVE JUST ABOUT MOVED EAST OF BOTH TAF SITES. EXPECT
THAT KRST WILL BE CLEAR BY 06Z WITH JUST SOME SCATTERED CLOUDS
LEFT FOR KLSE. THE GRADIENT AHEAD OF THE AREA OF HIGH PRESSURE
CENTERED OVER NEBRASKA IS EXPECTED TO KEEP THE WINDS AROUND 10
KNOTS FOR MOST OF THE NIGHT. THIS SHOULD PRODUCE ENOUGH MIXING TO
KEEP ANY FOG FROM FORMING...BUT IF THE WINDS DROP OFF SOME TOWARD
SUNRISE AS SUGGESTED BY THE 19.00Z NAM...THEN SOME FOG COULD
QUICKLY FORM WITH PLENTY OF LOW LEVEL MOISTURE IN PLACE FROM THE
SNOW MELT TODAY. THE AREA OF HIGH PRESSURE WILL MOVE INTO MISSOURI
OVERNIGHT AND THE INTO THE OHIO RIVER VALLEY WEDNESDAY. THIS WILL
ALLOW THE WINDS TO COME AROUND TO THE SOUTH WEDNESDAY AND INCREASE
TO OVER 10 KNOTS BY LATE AFTERNOON/EARLY EVENING FOR KRST. MID
LEVEL CLOUDS WILL ALSO OVER SPREAD THE AREA AHEAD OF THE THURSDAY
STORM SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
WIZ041>044-053>055-061.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
WIZ017-029-032>034-041-042-053-054.
WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR WIZ043-044-055-061.
MN...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
MNZ086>088-094>096.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ079-086-087-094-095.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ088-096.
IA...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
IAZ008>011-018-019-029-030.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ008>010-018-019-029.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ011-030.
&&
$$
UPDATE...BAUMGARDT
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1114 PM CST TUE FEB 18 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 321 PM CST TUE FEB 18 2014
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED SHORTWAVE TROUGHS OVER MANITOBA AND OVER EASTERN
SOUTH DAKOTA INTO NEBRASKA...RIDGING OVER THE NORTHERN
ROCKIES...AND A POTENT UPPER TROUGH JUST OFF THE BRITISH COLUMBIA
AND PACIFIC NORTHWEST COASTS. THIS POTENT UPPER TROUGH IS THE
CULPRIT FOR OUR THURSDAY STORM. DPVA AND PACIFIC MOISTURE AHEAD OF
THE TWO SHORTWAVE TROUGHS HAVE BEEN SPREADING MID AND HIGH CLOUDS
ACROSS THE FORECAST AREA TODAY. THESE CLOUDS HAVE LIMITED SOME
INSULATION...BUT SOUTHWESTERLY 925-850MB FLOW AHEAD OF A COLD
FRONT MOVING INTO THE FORECAST AREA HELPED BOOST TEMPERATURES INTO
THE 30S TO MID 40S THIS AFTERNOON. OVER WESTERN IOWA WHERE NO SNOW
EXISTS...READINGS ARE IN THE 50S TO LOW 60S. IN THE WAKE OF THE
COLD FRONT...READINGS ARE STILL IN THE 30S AND 40S...PARTIALLY DUE
TO A BIT MORE SUN AND DOWNSLOPING FLOW OFF THE NORTHERN ROCKIES.
THE QUIET BEFORE THE STORM PHRASE WORKS PERFECTLY FOR THE SHORT
TERM. 18.12Z MODEL GUIDANCE DEPICT THE RIDGING OVER THE NORTHERN
ROCKIES MARCHING EASTWARD TO ABOUT OVER THE FORECAST AREA BY 00Z
THU...PUSHED BY THE POTENT NORTHEAST PACIFIC NORTHWEST TROUGH
PLOWING INTO THE ROCKIES. ON THE EAST SIDE OF THE UPPER RIDGE AXIS
THERE IS A WEAK SHORTWAVE AT 500MB SUGGESTED TO DROP SOUTHEAST
THROUGH THE FORECAST AREA LATE TONIGHT...BUT THIS FEATURE WILL COME
THROUGH DRY WITH BASICALLY NO CLOUD.
ONLY REAL ISSUE TO CONTEND WITH TONIGHT IS IF ANY FOG CAN FORM
RESULTING FROM MELTING SNOW. ALL MODELS KEEP A DECENT PRESSURE
GRADIENT IN PLACE TONIGHT WITH A SURFACE RIDGE AXIS ONLY REACHING
WESTERN MN BY 12Z WED. 925MB WINDS STAY UP 20-30 KT FOR MUCH OF THE
NIGHT IN THE WAKE OF THE COLD FRONTAL PASSAGE THIS EVENING.
THUS...THINK ANY FOG WOULD BE LIMITED TO PERHAPS THE TYPICAL COLD
SPOTS AND SOME SMALL VALLEYS.
PLENTY OF SUN LOOKS ON TAP FOR WEDNESDAY...OUTSIDE OF SOME CLOUDS
INCREASING LATE AS THE RIDGE AXIS APPROACHES. 925MB TEMPS IN THE 0-
2C RANGE AT 18Z WED SUPPORTS HIGHS IN THE 30S TO A COUPLE
40S...WARMEST IN SOUTHWEST WI.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 321 PM CST TUE FEB 18 2014
...WINTER STORM FOR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
MANY FACETS OF THE STORM TO TALK ABOUT...
MODEL ANALYSIS...18.12Z GUIDANCE CONTINUES TO FOLLOW THE PAST COUPLE
OF CYCLES...PHASING TROUGHING OVER THE ROCKIES ON TOP OF THE
FORECAST AREA THURSDAY. THE PHASED UPPER TROUGH ALSO BECOMES
NEGATIVELY TITLED AS IT LIFTS THROUGH THE FORECAST AREA THURSDAY
EVENING. OVERALL...THE SPREAD IN GUIDANCE FROM 500MB TO THE SURFACE
IS FAIRLY LOW CONSIDERING THIS IS A PHASING TROUGH AND STILL ISNT
ONSHORE YET. THEREFORE...CONFIDENCE IS INCREASING THAT A HIGH IMPACT
WINTER STORM WILL AFFECT THE FORECAST AREA.
WINDS...MOST OF THE GUIDANCE IS IN AGREEMENT THAT AS THE PHASING
TAKES PLACE OF THE UPPER TROUGH...THE SURFACE LOW IS GOING TO
UNDERGO BOMBOGENESIS...DROPPING FROM A PRESSURE OF 995MB IN EASTERN
KS AT 12Z THU TO AROUND 970MB OVER LAKE SUPERIOR AT 12Z FRI. TO
HANDLE THIS PRESSURE DROP AND THE COLD AIR THAT GETS PULLED
IN...925MB WINDS INCREASE OUT OF THE WEST-NORTHWEST AT 30-50 KT ON
THE BACK SIDE OF THE STORM FOR THURSDAY EVENING. THE STRONGEST CORE
TRACKS ACROSS SOUTHEAST MN AND NORTHEAST IOWA...THE FAVORABLE
BLIZZARD AREA.
PRECIPITATION...THERE IS SOME UNCERTAINTY ON HOW QUICK PRECIPITATION
DEVELOPS. GFS/NAM/ECMWF SOUNDINGS DEPICT A DECENT DRY LAYER BETWEEN
900-700MB WEDNESDAY NIGHT...WITH MUCH OF THE LIFT FROM WARM
ADVECTION IN THAT LAYER VERSUS IN THE MID/HIGH CLOUDS ABOVE IT.
PRECIPITATION SHOULD STAND A MUCH BETTER CHANCE MOVING IN
THURSDAY...LIKELY SOUTH TO NORTH...AS THE STORM SYSTEM MOVES INTO
SOUTHERN WI. DURING THE AFTERNOON...FRONTOGENESIS IN THE MID/UPPER
LEVELS REALLY INTENSIFIES WITH THE APPROACH OF THE UPPER TROUGH...
WHICH SHOULD DEVELOP A STRONG AND HEAVY PRECIPITATING COLD CONVEYOR
BELT. PRECIPITABLE WATER PROGGED BETWEEN 0.5-0.75 INCHES OR 200-250
PERCENT OF NORMAL SUGGESTS PLENTY OF MOISTURE AVAILABLE FOR THE
FORCING TO PRODUCE FAIRLY HEAVY QPF. CROSS-SECTIONS EVEN SHOW A
LARGE AREA OF NEGATIVE EPV AND SOME WEAK CAPE IN THE AFTERNOON...
SUGGESTING THUNDER COULD OCCUR. WILL SEE IF THIS TRENDS HOLDS WITH
LATER MODELS. COLD CONVEYOR BELT WILL GRADUALLY LIFT INTO THE U.P.
OF MI THU NIGHT...GRADUALLY ENDING PRECIPITATION SOUTHWEST TO
NORTHEAST.
PRECIPITATION TYPE...A DRY WARM LAYER ALOFT SHOULD RESIDE OVER THE
FORECAST AREA WEDNESDAY NIGHT. AS THE PRECIPITATION SPREADS IN LATE
WEDNESDAY NIGHT/THURSDAY MORNING...THAT COULD FALL AS EITHER
SLEET...FREEZING RAIN OR RAIN UNTIL EVAPORATIVE COOLING SWITCHES IT
OVER TO SNOW. THE AFTERNOON IS TRICKY AND COMPLETELY DEPENDS ON THE
850MB LOW TRACK. AHEAD OF THE 850MB LOW...A WARM LAYER ALOFT AND AT
THE SURFACE WILL ADVECT NORTH...RESULTING IN A MIX OR COMPLETELY
SWITCHOVER TO RAIN. RIGHT NOW THIS SEEMS MOST PROBABLE TO OCCUR IN
FAR SOUTHEAST SECTIONS OF THE FORECAST AREA FROM 15-21Z THU. IF THE
LOW TRACKS FARTHER NORTHWEST LIKE THE 18.12Z UKMET...THEN RAIN COULD
FALL EVEN AT LA CROSSE. HOWEVER...THE UKMET IS A NORTHWEST OUTLIER.
SNOW AMOUNTS/ICE ACCUMULATION...ANY ICE ACCUMULATION LOOKS TO BE
LATE WEDNESDAY NIGHT FROM THE INITIAL WARM LAYER. EVEN SNOW AMOUNTS
REALLY DO NOT START TO PICK UP UNTIL LATE THURSDAY MORNING WHEN
HEAVIER PRECIPITATION BEGINS TO DEVELOP. DURING THURSDAY AFTERNOON
AND EVENING...1 TO 2 INCH PER HOUR RATES ARE POSSIBLE...ESPECIALLY
IF CONVECTION FORMS. PRESENTLY DEPICT 2 TO 10 INCHES FOR
TOTALS...HIGHEST IN NORTH CENTRAL WI WHERE THE LONGEST DURATION OF
SNOW IS EXPECTED. IMPORTANT...THESE AMOUNTS ARE SUBJECT TO
CHANGE...AS EVEN THE NEW 18.18Z NAM SUGGESTS OF A FOOT IN SOUTHEAST
MN.
...REST OF THE LONG TERM PERIOD...
AFTER THE WINTER STORM...THE WEATHER GETS QUIET. 18.12Z
ECMWF/CANADIAN/GFS AND ENSEMBLE DATA REMAIN CONSISTENT IN FORMING AN
OMEGA BLOCK FROM THE U.S. WEST COAST INTO ALASKA...RESULTING IN DEEP
TROUGHING OVER MUCH OF CANADA AND INTO THE UPPER MIDWEST. THIS
ALLOWS FOR A GRADUAL COOLING TREND FROM FRIDAY THROUGH NEXT
TUESDAY...AND ACCORDING TO THE CFS WOULD CONTINUE THROUGH THE REST
OF THE MONTH. WIND CHILLS THROUGH TUESDAY LOOK TO STAY JUST ABOVE
WIND CHILL ADVISORY CRITERIA...I.E. -20 F. DESPITE THE COOLING
TREND...THERE ARE NOT THAT MANY PRECIPITATING SYSTEMS TO DEAL WITH.
THERE ARE SOME HINTS OF A WEAK SHORTWAVE CROSSING THE SOUTHERN
PORTION OF THE FORECAST AREA FRIDAY NIGHT WITH SOME LIGHT SNOW.
LOOKING OUT TO MONDAY AND MONDAY NIGHT OUR SOUTHERN FORECAST AREA
COULD ALSO GET CLIPPED BY A MID LEVEL FRONTOGENESIS BAND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1113 PM CST TUE FEB 18 2014
BAND OF CLOUDS ASSOCIATED WITH A SHORT WAVE TROUGH MOVING ACROSS
THE REGION HAVE JUST ABOUT MOVED EAST OF BOTH TAF SITES. EXPECT
THAT KRST WILL BE CLEAR BY 06Z WITH JUST SOME SCATTERED CLOUDS
LEFT FOR KLSE. THE GRADIENT AHEAD OF THE AREA OF HIGH PRESSURE
CENTERED OVER NEBRASKA IS EXPECTED TO KEEP THE WINDS AROUND 10
KNOTS FOR MOST OF THE NIGHT. THIS SHOULD PRODUCE ENOUGH MIXING TO
KEEP ANY FOG FROM FORMING...BUT IF THE WINDS DROP OFF SOME TOWARD
SUNRISE AS SUGGESTED BY THE 19.00Z NAM...THEN SOME FOG COULD
QUICKLY FORM WITH PLENTY OF LOW LEVEL MOISTURE IN PLACE FROM THE
SNOW MELT TODAY. THE AREA OF HIGH PRESSURE WILL MOVE INTO MISSOURI
OVERNIGHT AND THE INTO THE OHIO RIVER VALLEY WEDNESDAY. THIS WILL
ALLOW THE WINDS TO COME AROUND TO THE SOUTH WEDNESDAY AND INCREASE
TO OVER 10 KNOTS BY LATE AFTERNOON/EARLY EVENING FOR KRST. MID
LEVEL CLOUDS WILL ALSO OVER SPREAD THE AREA AHEAD OF THE THURSDAY
STORM SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR WIZ017-029-032>034-041>044-053>055-061.
MN...BLIZZARD WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT
FOR MNZ086-087-094-095.
WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR MNZ079-088-096.
IA...BLIZZARD WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT
FOR IAZ008>010-018-019-029.
WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR IAZ011-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1117 PM MST THU FEB 20 2014
.UPDATE...
ISSUED AT 1115 PM MST THU FEB 20 2014
AFTER A LOOK AT THE 00Z GFS MODEL AND WHAT IS NOT HAPPENING ON
SATELLITE...WE HAVE CANCELLED THE WINTER WEATHER ADVISORIES OVER
THE NORTHERN COLORADO MTNS. THANKS TO PUB FOR COORDINATION.
UPDATE ISSUED AT 945 PM MST THU FEB 20 2014
SURFACE HIGH PRESSURE IS CENTERED OVER THE FOUR CORNERS AREA
TONIGHT BRINGING STRONGER INVERSIONS TO THE SOUTH AND THUS MUCH
COLDER TEMPERATURES THAN 24 HRS AGO. THE GRADIENT REMAINS TIGHT
ACROSS THE NORTH ESPECIALLY ALONG THE PARK/GORE RANGES. CLOUDS ARE
STRETCHED ALONG THE WYOMING BORDER AND ALONG THE CONTINENTAL
DIVIDE.
CONCERNING THE ADVISORIES IN THE NW COLORADO MTNS...THE 00Z NAM
PRODUCES ONLY VERY LIGHT SNOW ACROSS THE EASTERN MTNS TONIGHT AND
EVEN INTO FRIDAY. NAM AND RAP FORECAST SOUNDINGS SHOW THE PROFILE
BECOMING MUCH MORE STABLE IN MILD 700MB WARM ADVECTION BUT ALSO
THE PROFILE IS NOT FULLY SATURATING. THE PROFILE BECOMES MILDLY
UNSTABLE THROUGH A SHALLOW LAYER TO ABOUT 11KFT ON FRIDAY. ITS NOT
UNTIL AROUND SUNSET FRIDAY THAT A 100KT JET NOSES IN FROM THE NW
AND PRODUCES SOME ADDITIONAL FORCING THAT SNOW REALLY STARTS TO
ACCUMULATE. WILL LOOK CLOSELY AT THE NEW GFS AND THE CURRENT
HIGHLIGHTS TONIGHT.
ELSEWHERE AFTER A COLD START TO THE DAY EXPECT PERIODS OF CLOUDS
AND DAYTIME TEMPERATURES RECOVERING TO JUST BELOW NORMAL.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 344 PM MST THU FEB 20 2014
THE LAST STORM SYSTEM HAS MOVED ONTO THE PLAINS WHERE IT IS
PRODUCING SEVERE WEATHER THIS AFTERNOON. IN IT/S WAKE...COLDER
TEMPERATURES AND ISOLATED TO SCATTERED SHOWERS PERSIST ACROSS THE
DIVIDE MOUNTAINS. WINDS ALSO CONTINUE TO GUST OVER 35 MPH ALONG THE
SPINE OF THE ROCKIES AND THIS IS LIKELY TO CONTINUE OVER THE NEXT
FEW DAYS AS FAST NORTHWEST FLOW WAVERS OVER SOUTHERN WYOMING AND
NORTHERN COLORADO. THE INFUSION OF PACIFIC MOISTURE AND EMBEDDED
ENERGY WILL BRING WAVES OF SNOW TO THE REGION WITH THE NEXT BATCH
EXPECTED OVERNIGHT. 290-300K MOISTURE TRANSPORT VECTORS SHOW THIS
MOISTURE ARRIVING THROUGH THE EVENING ALONG WITH AN INCREASE IN JET
LEVEL WINDS. WAA INCREASES WITH THE APPROACH OF MID LEVEL ENERGY
AND THIS DEEPENS THE DENDRITIC LAYER UP NORTH AS THE LOWER PORTION
OF THE SOUNDING APPROACHES ISOTHERMAL. NEGATIVE EPV VALUES JUST
ABOVE THIS LAYER ALSO SUGGEST SOME POTENTIAL FOR BETTER SNOWFALL
PRODUCTION ACROSS THE NORTHERN MOUNTAINS THROUGH SUNRISE. THOUGH
MID LEVEL TEMPERATURES ARE WARMING...AFTERNOON SOUNDING ALSO
SUGGEST STEEP LAPSE RATES REMAINING IN PLACE THROUGH THE DENDRITIC
LAYER. THIS SHOULD HELP PRODUCE SOME HEAVIER AREAS OF SNOWFALL AS
THE PRECIPITATION BECOMES MORE CONVECTIVE THROUGH THE AFTERNOON.
SNOW AMOUNTS IN THE 4-8 INCH RANGE EXPECTED OVER 9000 FEET IN
PORTIONS OF THE CENTRAL AND NORTHERN MOUNTAINS WITH LOCALLY HIGHER
ON FAVORED SLOPES. AGAIN FEEL THAT THE GUSTY WINDS AND NEAR
WHITEOUT CONDITIONS WILL KEEP A THREAT OF HAZARDOUS TRAVEL
CONDITIONS IN PLACE AND HAVE HOISTED AN ADVISORY THROUGH FRIDAY
EVENING. THERE LOOKS TO BE A SHORT BREAK MOVE THROUGH THE EARLY
MORNING HOURS ON SATURDAY BEFORE ANOTHER SURGE OF MID LEVEL ENERGY
AND JET LEVEL WINDS INCREASE SNOW INTENSITY ON SATURDAY. THE ONE
CAVEAT IS SNOW MAY NOT ENTIRELY END ACROSS THE PORTIONS OF THE
PARK AND GORE RANGE WHERE THE OROGRAPHIC WINDS REMAIN FAVORABLE.
TEMPERATURES THROUGH THIS TIME WILL GRADUALLY WARM...ESPECIALLY IN
THE LOWER VALLEYS OF THE SOUTHWEST WHERE HIGHS SHOULD REACH BACK
TOWARD NORMAL. THE MOUNTAINS WILL WARM AS WELL BUT STILL REMAIN
FAVORABLE FOR SNOW REACHING INTO THE HIGH VALLEYS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 344 PM MST THU FEB 20 2014
SNOW IS EXPECTED TO PICK UP AGAIN ACROSS THE NORTHERN CO MTNS SAT
AND SAT NIGHT AS ANOTHER WAVE EMBEDDED IN THE NORTHWEST FLOW
PASSES. 30-40 KT WESTERLY WINDS AT MTN TOP LEVEL WILL CONTINUE THE
WINDY CONDITIONS UP HIGH WITH AREAS OF BLOWING SNOW. SNOW LIKELY
TO EXTEND AS FAR SOUTH AS PERHAPS CRESTED BUTTE BUT ACCUMULATIONS
SHOULD TAPER RATHER QUICKLY SOUTH OF I-70. A DECREASING CHANCE OF
SNOW WILL LINGER ACROSS THE NORTHERN CO MTNS SUNDAY.
A HIGH AMPLITUDE RIDGE IS EXPECTED ALONG THE WEST COAST OF NORTH
AMERICA THE FIRST HALF OF NEXT WEEK WHILE A LARGE AREA OF LOW
PRESSURE RESIDES OVER ERN CANADA. THIS WILL GENERALLY KEEP DRIER
NORTHWEST FLOW ACROSS OUR FORECAST AREA BUT SHIFT JET STREAM TO OUR
NORTHEAST AS THE RIDGE BUILDS INTO THE GREAT BASIN. MODELS SHOW A
SMALL DISTURBANCE MOVING EAST ACROSS THE 4 CORNERS MONDAY FOR SOME
CLOUDS BUT NO PRECIP. MODELS ALSO SHOW A DISTURBANCE ROTATING AROUND
THE CANADIAN LOW BRUSHING OUR NORTHERN MTNS TUE-WED FOR A SLIGHT
CHANCE/CHANCE OF SNOW THERE. TEMPS WILL BE SEASONABLE.
A STRONG WESTERLY PACIFIC JET IS SHOWN UNDERCUTTING THE WESTERN
RIDGE AFTER WEDNESDAY AND QUICKLY PUNCHES MOISTURE INLAND ACROSS THE
GREAT BASIN. MODELS ARE IN GOOD AGREEMENT HERE...SO PRECIP CHANCES
SHOULD BE INCREASING THE LAST HALF OF NEXT WEEK. BUT WITH THE AIR
ORIGINATING OVER THE PACIFIC...WILL PROBABLY BE SEEING SNOW LEVELS
ON THE RISE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 945 PM MST THU FEB 20 2014
VFR CONDITIONS DOMINATE WITH CIGS 060-070 ONLY AT KCAG KHDN KSBS.
VFR CIGS WILL INCREASE ACROSS MUCH OF THE REGION TONIGHT. LOWERING
CLOUDS AND INCREASING PRECIPITATION OVER THE NORTHERN AND CENTRAL
COLORADO MOUNTAINS WILL BEGIN TO IMPACT THE KEGE AND KASE FLIGHT
TERMINALS TOWARD 12Z. LOWERED FLIGHT CRITERIA AT THESE TERMINALS
MAY PERSIST INTO THE AFTERNOON HOURS ON FRIDAY AS SNOW SHOWERS
PASS BY...BUT THEY SHOULD SHOW A GENERAL UPWARD TREND TOWARD VFR.
THE REMAINING FLIGHT TERMINALS SHOULD REMAIN AT VFR LEVELS. GUSTY
MOUNTAIN TOP WINDS WILL LEAD TO MECHANICAL TURBULENCE THROUGH THE
NEXT 24 HOURS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATES...JOE
SHORT TERM...15
LONG TERM...JAD
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
947 PM MST THU FEB 20 2014
.UPDATE...
ISSUED AT 945 PM MST THU FEB 20 2014
SURFACE HIGH PRESSURE IS CENTERED OVER THE FOUR CORNERS AREA
TONIGHT BRINGING STRONGER INVERSIONS TO THE SOUTH AND THUS MUCH
COLDER TEMPERATURES THAN 24 HRS AGO. THE GRADIENT REMAINS TIGHT
ACROSS THE NORTH ESPECIALLY ALONG THE PARK/GORE RANGES. CLOUDS ARE
STRETCHED ALONG THE WYOMING BORDER AND ALONG THE CONTINENTAL
DIVIDE.
CONCERNING THE ADVISORIES IN THE NW COLORADO MTNS...THE 00Z NAM
PRODUCES ONLY VERY LIGHT SNOW ACROSS THE EASTERN MTNS TONIGHT AND
EVEN INTO FRIDAY. NAM AND RAP FORECAST SOUNDINGS SHOW THE PROFILE
BECOMING MUCH MORE STABLE IN MILD 700MB WARM ADVECTION BUT ALSO
THE PROFILE IS NOT FULLY SATURATING. THE PROFILE BECOMES MILDLY
UNSTABLE THROUGH A SHALLOW LAYER TO ABOUT 11KFT ON FRIDAY. ITS NOT
UNTIL AROUND SUNSET FRIDAY THAT A 100KT JET NOSES IN FROM THE NW
AND PRODUCES SOME ADDITIONAL FORCING THAT SNOW REALLY STARTS TO
ACCUMULATE. WILL LOOK CLOSELY AT THE NEW GFS AND THE CURRENT
HIGHLIGHTS TONIGHT.
ELSEWHERE AFTER A COLD START TO THE DAY EXPECT PERIODS OF CLOUDS
AND DAYTIME TEMPERATURES RECOVERING TO JUST BELOW NORMAL.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 344 PM MST THU FEB 20 2014
THE LAST STORM SYSTEM HAS MOVED ONTO THE PLAINS WHERE IT IS
PRODUCING SEVERE WEATHER THIS AFTERNOON. IN IT/S WAKE...COLDER
TEMPERATURES AND ISOLATED TO SCATTERED SHOWERS PERSIST ACROSS THE
DIVIDE MOUNTAINS. WINDS ALSO CONTINUE TO GUST OVER 35 MPH ALONG THE
SPINE OF THE ROCKIES AND THIS IS LIKELY TO CONTINUE OVER THE NEXT
FEW DAYS AS FAST NORTHWEST FLOW WAVERS OVER SOUTHERN WYOMING AND
NORTHERN COLORADO. THE INFUSION OF PACIFIC MOISTURE AND EMBEDDED
ENERGY WILL BRING WAVES OF SNOW TO THE REGION WITH THE NEXT BATCH
EXPECTED OVERNIGHT. 290-300K MOISTURE TRANSPORT VECTORS SHOW THIS
MOISTURE ARRIVING THROUGH THE EVENING ALONG WITH AN INCREASE IN JET
LEVEL WINDS. WAA INCREASES WITH THE APPROACH OF MID LEVEL ENERGY
AND THIS DEEPENS THE DENDRITIC LAYER UP NORTH AS THE LOWER PORTION
OF THE SOUNDING APPROACHES ISOTHERMAL. NEGATIVE EPV VALUES JUST
ABOVE THIS LAYER ALSO SUGGEST SOME POTENTIAL FOR BETTER SNOWFALL
PRODUCTION ACROSS THE NORTHERN MOUNTAINS THROUGH SUNRISE. THOUGH
MID LEVEL TEMPERATURES ARE WARMING...AFTERNOON SOUNDING ALSO
SUGGEST STEEP LAPSE RATES REMAINING IN PLACE THROUGH THE DENDRITIC
LAYER. THIS SHOULD HELP PRODUCE SOME HEAVIER AREAS OF SNOWFALL AS
THE PRECIPITATION BECOMES MORE CONVECTIVE THROUGH THE AFTERNOON.
SNOW AMOUNTS IN THE 4-8 INCH RANGE EXPECTED OVER 9000 FEET IN
PORTIONS OF THE CENTRAL AND NORTHERN MOUNTAINS WITH LOCALLY HIGHER
ON FAVORED SLOPES. AGAIN FEEL THAT THE GUSTY WINDS AND NEAR
WHITEOUT CONDITIONS WILL KEEP A THREAT OF HAZARDOUS TRAVEL
CONDITIONS IN PLACE AND HAVE HOISTED AN ADVISORY THROUGH FRIDAY
EVENING. THERE LOOKS TO BE A SHORT BREAK MOVE THROUGH THE EARLY
MORNING HOURS ON SATURDAY BEFORE ANOTHER SURGE OF MID LEVEL ENERGY
AND JET LEVEL WINDS INCREASE SNOW INTENSITY ON SATURDAY. THE ONE
CAVEAT IS SNOW MAY NOT ENTIRELY END ACROSS THE PORTIONS OF THE
PARK AND GORE RANGE WHERE THE OROGRAPHIC WINDS REMAIN FAVORABLE.
TEMPERATURES THROUGH THIS TIME WILL GRADUALLY WARM...ESPECIALLY IN
THE LOWER VALLEYS OF THE SOUTHWEST WHERE HIGHS SHOULD REACH BACK
TOWARD NORMAL. THE MOUNTAINS WILL WARM AS WELL BUT STILL REMAIN
FAVORABLE FOR SNOW REACHING INTO THE HIGH VALLEYS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 344 PM MST THU FEB 20 2014
SNOW IS EXPECTED TO PICK UP AGAIN ACROSS THE NORTHERN CO MTNS SAT
AND SAT NIGHT AS ANOTHER WAVE EMBEDDED IN THE NORTHWEST FLOW
PASSES. 30-40 KT WESTERLY WINDS AT MTN TOP LEVEL WILL CONTINUE THE
WINDY CONDITIONS UP HIGH WITH AREAS OF BLOWING SNOW. SNOW LIKELY
TO EXTEND AS FAR SOUTH AS PERHAPS CRESTED BUTTE BUT ACCUMULATIONS
SHOULD TAPER RATHER QUICKLY SOUTH OF I-70. A DECREASING CHANCE OF
SNOW WILL LINGER ACROSS THE NORTHERN CO MTNS SUNDAY.
A HIGH AMPLITUDE RIDGE IS EXPECTED ALONG THE WEST COAST OF NORTH
AMERICA THE FIRST HALF OF NEXT WEEK WHILE A LARGE AREA OF LOW
PRESSURE RESIDES OVER ERN CANADA. THIS WILL GENERALLY KEEP DRIER
NORTHWEST FLOW ACROSS OUR FORECAST AREA BUT SHIFT JET STREAM TO OUR
NORTHEAST AS THE RIDGE BUILDS INTO THE GREAT BASIN. MODELS SHOW A
SMALL DISTURBANCE MOVING EAST ACROSS THE 4 CORNERS MONDAY FOR SOME
CLOUDS BUT NO PRECIP. MODELS ALSO SHOW A DISTURBANCE ROTATING AROUND
THE CANADIAN LOW BRUSHING OUR NORTHERN MTNS TUE-WED FOR A SLIGHT
CHANCE/CHANCE OF SNOW THERE. TEMPS WILL BE SEASONABLE.
A STRONG WESTERLY PACIFIC JET IS SHOWN UNDERCUTTING THE WESTERN
RIDGE AFTER WEDNESDAY AND QUICKLY PUNCHES MOISTURE INLAND ACROSS THE
GREAT BASIN. MODELS ARE IN GOOD AGREEMENT HERE...SO PRECIP CHANCES
SHOULD BE INCREASING THE LAST HALF OF NEXT WEEK. BUT WITH THE AIR
ORIGINATING OVER THE PACIFIC...WILL PROBABLY BE SEEING SNOW LEVELS
ON THE RISE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 945 PM MST THU FEB 20 2014
VFR CONDITIONS DOMINATE WITH CIGS 060-070 ONLY AT KCAG KHDN KSBS.
VFR CIGS WILL INCREASE ACROSS MUCH OF THE REGION TONIGHT. LOWERING
CLOUDS AND INCREASING PRECIPITATION OVER THE NORTHERN AND CENTRAL
COLORADO MOUNTAINS WILL BEGIN TO IMPACT THE KEGE AND KASE FLIGHT
TERMINALS TOWARD 12Z. LOWERED FLIGHT CRITERIA AT THESE TERMINALS
MAY PERSIST INTO THE AFTERNOON HOURS ON FRIDAY AS SNOW SHOWERS
PASS BY...BUT THEY SHOULD SHOW A GENERAL UPWARD TREND TOWARD VFR.
THE REMAINING FLIGHT TERMINALS SHOULD REMAIN AT VFR LEVELS. GUSTY
MOUNTAIN TOP WINDS WILL LEAD TO MECHANICAL TURBULENCE THROUGH THE
NEXT 24 HOURS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 11 PM MST FRIDAY ABOVE 9000 FEET
FOR COZ004-010-013.
UT...NONE.
&&
$$
UPDATE...JOE
SHORT TERM...15
LONG TERM...JAD
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS ALBANY NY
327 AM EST FRI FEB 21 2014
.SYNOPSIS...
AHEAD OF A COLD FRONT...MILDER AIR WILL MOVE INTO THE REGION FOR
TODAY...ALONG WITH RAIN SHOWERS...GUSTY WINDS OVER THE HIGH
TERRAIN...AND A SLIGHT CHANCE FOR A THUNDERSTORM. AFTER THE FRONT
PASSES THROUGH THE REGION LATE TODAY...THE THREAT FOR RAIN SHOWERS
WILL END. DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL INTO
THE WEEKEND...BUT MUCH COLDER AIR WILL RETURN TO THE REGION FOR MUCH
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 327 AM EST...A STRONG STORM SYSTEM AND POTENT UPPER LEVEL
SHORTWAVE IS MOVING ACROSS THE UPPER GREAT LAKES. A WARM FRONT
ASSOCIATED WITH THIS STORM IS HAVING A TOUGH TIME MOVING ACROSS
OUR REGION...DUE TO PLENTY OF LOW LEVEL COLD AIR IN PLACE THANKS
TO A DEEP SNOW PACK. TEMPERATURES CONTINUE TO BE IN THE LOWER TO
MIDDLE 30S ACROSS THE REGION.
WITH TEMPS ALOFT WELL ABOVE FREEZING...A BAND OF STEADY RAIN AND /IN
AREAS WHERE SURFACE TEMPERATURES REMAIN BELOW FREEZING/ FREEZING
RAIN IS MOVING ACROSS THE NORTHERN HALF OF THE AREA DUE TO STRONG
ISENTROPIC LIFT/WARM AIR ADVECTION. ALTHOUGH SOME FREEZING RAIN IS
STILL OCCURRING IN SHELTERED VALLEYS OF THE ADIRONDACKS AND SRN
GREEN MOUNTAINS...SFC TEMPS WILL GRADUALLY WARM UP ABOVE FREEZING
ACROSS THE ENTIRE REGION BY THE MID MORNING HOURS. THIS WILL END THE
THREAT FOR FREEZING RAIN. UNTIL THEN...AN ADDITIONAL TRACE TO TWO
TENTHS OF AN INCH OF ICE WILL BE POSSIBLE FOR THESE ISOLATED AREAS.
MOST OTHER LOCATIONS WILL JUST SEE A PLAIN RAIN...BUT WITH TEMPS
BARELY ABOVE FREEZING...PLENTY OF SLUSH WILL REMAIN AROUND...AND
SOME SURFACES MAY STILL BE ICY OR SLIPPERY DUE TO RECENT SNOW/SLEET
FROM LAST EVENING. WINTER WEATHER ADVISORIES REMAIN IN EFFECT FOR
NORTHERN PORTIONS OF THE AREA TO ACCOUNT FOR THIS ISOLATED FREEZING
RAIN POTENTIAL...BUT SHOULD BE ABLE TO BE CANCELLED/ALLOWED TO
EXPIRE LATER THIS MORNING.
THERE LOOKS TO BE A BREAK IN THE STEADY PRECIP DURING BETWEEN ABOUT
SUNRISE AND EARLY AFTERNOON...AS SEEN IN THE 05Z 3KM HRRR AND 00Z
NAM12...AS THE BEST ISENTROPIC LIFT SHIFTS NORTHWARD AND THE STORM/S
COLD FRONT CONTINUES TO REMAIN UPSTREAM ACROSS WESTERN NY.
HOWEVER...WE WILL STILL KEEP POPS RATHER HIGH FOR THE MORNING...AS
SOME LIGHT RAIN SHOWERS OR DRIZZLE MAY BE PASSING THROUGH THE
REMAINDER DUE TO THE MOIST SOUTHERLY FLOW...ESP IN UPSLOPE FAVORED
AREAS. MAX TEMPS SHOULD WARM UP INTO THE LOWER TO MID 40S FOR VALLEY
AREAS...WITH UPPER 30S IN THE HIGH TERRAIN WITH THESE HIGHS IN THE
LATE MORNING TO EARLY AFTERNOON.
THE STORM/S COLD FRONT LOOKS TO MOVE FROM WEST TO EAST DURING THE
AFTERNOON HOURS. A STRONGLY FORCED LINE OF SHOWERS...AND POSSIBLY
SOME ISOLATED THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS IS
SEEN IN THE 3KM HRRR AS WELL...WITH THE TIMING ACROSS OUR AREA BASICALLY
FROM 1 PM THROUGH 4 PM. SHOWALTER VALUES LOOK TO BE JUST BELOW
ZERO...SO SOME ELEVATED INSTABILITY IS POSSIBLE FOR A RUMBLE OR
TWO OF THUNDER...BUT NO STRONG/SEVERE STORMS ARE ANTICIPATED DUE
TO MEAGER SURFACE BASED INSTABILITY. ONCE THE FRONT GOES
THROUGH...THE THREAT FOR SHOWERS WILL DIMINISH GREATLY...AND TEMPS
WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION
AT SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY
QPF WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER
QUICKLY. WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH
EXPECTED COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE
SNOW...PERHAPS MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR
VALLEY AREAS. JUST AN INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR
NOW...WILL JUST GO WITH CHC POPS FOR SUN/SUN NIGHT DUE TO
UNCERTAINTY REGARDING ITS EXACT TRACK/TIMING. MAX TEMPS WILL BE IN
THE 30S...AND MINS SUNDAY NIGHT LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
THE NEXT BATCH OF PCPN IS MOVING QUICKLY EAST INTO THE HUDSON VALLEY
AT THIS HOUR. MOST OF THE PCPN WILL BE IN THE FORM OF RAIN WITH
POCKETS OF SLEET. THIS WILL RESULT IN MVFR/IFR CONDITIONS FOR MUCH
OF THE TAF PERIOD. FRIDAY DURING THE DAY THE PCPN TYPE SHOULD BE ALL
RAIN. SOLID IFR/LIFR EXPECTED THROUGH MUCH OF THE DAY ON FRIDAY
MORNING DUE TO RELATIVELY WARM/MOIST AIR MOVING OVER A DEEP
SNOWPACK. RAIN WILL CONTINUE THROUGH MUCH OF FRIDAY BEFORE A COLD
FRONT PASSES THROUGH DURING THE AFTERNOON.
WINDS WILL BE SOUTH-SOUTHEAST AROUND 4-8 KT...BECOMING LIGHT AND
VARIABLE OVERNIGHT INTO FRIDAY MORNING. WINDS WILL SHIFT TO
SOUTHWEST AND WEST LATER FRIDAY AFTERNOON AT 10 KT OR LESS.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3+ FEET.
TEMPERATURES ARE CURRENTLY IN THE LOWER TO MIDDLE 30S...WITH STEADY
RAIN AND FREEZING RAIN OCCURRING ACROSS THE NORTHERN HALF OF THE
REGION AS A WARM FRONT MOVES ACROSS THE REGION. WITH A SOUTHERLY
FLOW DEVELOPING...TEMPERATURES WILL BRIEFLY BE ABOVE NORMAL
TODAY...WITH HIGHS IN THE UPPER 30S TO MID 40S...ALONG WITH SOME
ADDITIONAL RAIN SHOWERS. HOWEVER...COLDER AIR WILL QUICKLY RETURN
BEHIND THIS AFTERNOON/S COLD FRONT...WITH TEMPERATURES DROPPING BACK
BELOW FREEZING ACROSS THE ENTIRE REGION BY TONIGHT.
STORM TOTAL QPF WILL BE A HALF INCH TO NEARLY ONE AND A HALF
INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DAYTIME TEMPERATURES OVER THE WEEKEND WILL CONTINUE TO BE ABOVE
FREEZING...AND OVERNIGHT LOWS WILL DROP BELOW FREEZING. THIS SHOULD
ALLOW FOR A STEADY CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY
FLOODING CONCERNS. MUCH COLDER WEATHER...WITH TEMPERATURES
COMPLETELY BELOW FREEZING...WILL RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION A SLIGHT CHC FOR AN ISOLATED ICE JAM ON
SMALLER STREAMS AND CREEK IN THE HWO STATEMENT FOR TODAY INTO
TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT WIDESPREAD
FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ033-039>043-048>050-082>084.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NYZ032-038-047-051>054.
MA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
504 AM EST FRI FEB 21 2014
.UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
&&
.PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
AVIATION...
06Z UPDATE...
LINE OF SHOWERS AND THUNDERSTORMS EXPECTED TO MOVE THROUGH THE
AREA OVERNIGHT...WITH DEGRADING CIGS AND VSBYS ACCOMPANYING THE
TSRA. HAVE TIMED THE SQUALL LINE THROUGH THE ATL AREA BY 10Z...AND
THE MCN AND AHN AREAS BY AROUND 12Z. S-SW GUSTY WINDS /15G25KT OR
SO/ WILL BECOME NW AT 13-15KT GUSTS TO 22-25KT BEHIND THE LINE.
EXPECT HIGH IFR OR LOW MVFR CIGS WITH THE POST-TSRA LIGHT
RAIN...WITH SLOW IMPROVEMENT THROUGH FRIDAY MORNING...AND VFR BY AFTERNOON.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 90 5 5 10
ATLANTA 61 39 66 43 / 70 5 5 10
BLAIRSVILLE 57 32 63 36 / 60 5 5 10
CARTERSVILLE 61 32 66 38 / 40 5 5 10
COLUMBUS 63 39 67 41 / 80 5 5 20
GAINESVILLE 62 38 65 40 / 70 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 20 5 5 10
PEACHTREE CITY 61 30 66 36 / 70 5 5 10
VIDALIA 68 45 70 46 / 90 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 9 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: BARROW...BIBB...BUTTS...CARROLL...
CHATTAHOOCHEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...
CRISP...DEKALB...DOOLY...DOUGLAS...FAYETTE...GREENE...GWINNETT...
HARALSON...HARRIS...HEARD...HENRY...HOUSTON...JASPER...JONES...
LAMAR...MACON...MARION...MERIWETHER...MONROE...MORGAN...
MUSCOGEE...NEWTON...NORTH FULTON...OCONEE...OGLETHORPE...
PAULDING...PEACH...PIKE...POLK...PUTNAM...ROCKDALE...SCHLEY...
SOUTH FULTON...SPALDING...STEWART...SUMTER...TALBOT...TAYLOR...
TROUP...UPSON...WALTON...WEBSTER.
&&
$$
SHORT TERM...31
LONG TERM....39
AVIATION...31
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
421 AM EST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT EASTWARD TONIGHT IN ADVANCE OF AN APPROACHING
COLD FRONT. THE COLD FRONT WILL SWEEP THROUGH THE AREA ON FRIDAY...STALLING
JUST OFFSHORE UNTIL STRONGER HIGH PRESSURE BUILDS INTO THE AREA ON
MONDAY. A LOW PRESSURE SYSTEM COULD DEVELOP OFF THE SOUTHEAST COAST
LATE TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...IMPRESSIVE COOL SEASON NOCTURNAL WARM AIR ADVECTION PATTERN
IN FULL TILT WITH TEMPS WARMING INTO THE MID TO UPPER 60S OVERNIGHT
AS MIXING FROM THE LOW LEVEL JET RESULTING IN AN INCREASING SSW
BREEZE MANY LOCATIONS...ESPECIALLY ALONG AND E OF I-95. THIS HAS
REDUCED POTENTIAL FOR FOG AND MOST RECENT WEB CAMS ALONG THE
BEACHES HAVE BEEN FOG FREE FOR MUCH OF THE OVERNIGHT. THERE STILL
IS POTENTIAL FOR SOME DENSE SEA FOG TO BRUSH THE COAST BUT LATEST
THINKING IS FOR MORE OF A TRANSIENT/PATCHY SCENARIO AND HAVE
ALLOWED LAND-BASED FOG ADVISORIES TO COME DOWN. MOST AREAS WILL
REMAIN DRY AT DAWN BUT CONVECTIVE RAINS WILL BE NEARING OUR FAR
INLAND ZONES AT THAT TIME. WE CANCELLED A DENSE FOG ADVISORY FOR
COASTAL ZONES THIS MORNING GIVEN ONGOING OBSERVATION/SATELLITE
TRENDS.
A STRONG MID LEVEL SHORT WAVE RIDING BELOW THE LARGE/DEEP CLOSED UPPER
LOW OVER THE GREAT LAKES WAS IMPRESSIVE EARLY THIS MORNING ON WATER
VAPOR SATELLITE IMAGERY. THIS FEATURE WILL DIG THE MEAN UPPER TROUGH
THROUGH THE TENNESSEE/OHIO VALLEYS THIS MORNING THEN LIFT TOWARD NEW
ENGLAND LATE TODAY. SUBTLE NEGATIVE TILTING APPEARS TO BE STRONGER
OFF TO THE NORTH OF OUR FORECAST AREA THROUGH MID AFTERNOON.
ONGOING TRENDS THIS MORNING HAVE INCREASED OUR CONCERNS FOR SEVERE
WEATHER POTENTIAL IN THE PRE-FRONTAL ENVIRONMENT THROUGH MID
AFTERNOON. THE FIRST...OBVIOUSLY THE MUCH WARMER THAN GUIDANCE
READINGS THAT HAVE BECOME ROOTED ACROSS SE GEORGIA AND EASTERN SOUTH
CAROLINA EARLY THIS MORNING BEFORE DAYBREAK. ALTHOUGH TIMING OF
THE CONVECTIVE LINE THROUGH THE FORECAST AREA REMAINS FAIRLY
CONSISTENT FROM PREVIOUS MODEL RUNS TODAY...IT IS NOT GOING TO
TAKE MUCH TO ALLOW TEMPS TO RISE WARMER INTO THE LOWER TO MID 70S
THIS MORNING. UPSTREAM CONVECTION OVERNIGHT HAS BEEN QUITE
ROBUST WITH THE LATEST RAP SHOWING SURFACE BASED INSTABILITY INTO SW
GEORGIA WITH SBCAPES OVER 750 J/KG AT 08Z. SOME OF FORECAST AREAS
COULD SEE SOME THINNER CLOUDS THROUGH MID MORNING AS DENSE CLOUD
COVER WILL BE COMING IN LATER IN THE MORNING.
SPC HAS OUR REGION IN A SLIGHT RISK OF SEVERE CONVECTION AND THERE
APPEARS TO BE NO REASON TO DOUBT IT PER LATEST MESOSCALE TRENDS.
00Z HIGH RESOLUTION GUIDANCE INDICATING POTENTIAL FOR HIGHER DBZ CORES
AND LINEAR ORGANIZATION. GIVEN THE STRONG WIND FIELDS...SMALL BOWS
WOULD BE A CONCERN ALONG WITH POSSIBLE FORMATION OF A DECENT REAR
INFLOW JET. CONCERN FALLS OVER OUR NW TIER OF ZONES THAT SUFFERED
GREAT TIMBER DAMAGE FROM THE RECENT ICE STORM. TSTM GUST IMPACTS
COULD CERTAINLY BE MUCH GREATER IN THOSE ZONES WHERE WEAK AND
BROKEN LIMBS ALREADY LACE THAT REGION. EVEN A MARGINALLY GUSTY
SQUALL LINE COULD MAKE FOR SOME BAD TIMES IN SOME AREAS AND WE
WILL REMAIN COGNIZANT OF THIS SITUATION. WE WILL RAMP UP SEVERE
WORDING A BIT IN OUR HAZARDOUS WEATHER OUTLOOK THIS MORNING
ALTHOUGH IT IS STILL MORE LIKELY THAT WE ONLY SEE ONLY SEE
ISOLATED OCCURRENCES OF 50 KT CONVECTIVE WIND GUSTS IN THE
CONVECTIVE SEGMENTS/LINES AS TIMING AND STRENGTH OF DYNAMICS DO
NOT APPEAR TO COMPLETELY COME IN SYNC FOR A MORE WIDESPREAD
EVENT.
THE COLD FRONT WILL RACE THROUGH THE FORECAST AREA THIS AFTERNOON AND
OFFSHORE BY EARLY EVENING. MUCH COOLER TEMPS EXPECTED TONIGHT WITH
LOWS IN THE 40S AND GRADUALLY CLEARING SKIES.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
DRY HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY. AMPLE
MOISTURE WITHIN A 105 KT JET OVER THE DEEP SOUTH WILL PRODUCE
EXTENSIVE CIRRUS WHICH WILL SLIGHTLY LIMIT INSOLATION. HOWEVER HIGH
TEMPS WILL STILL REACH 70F IN MANY SPOTS.
ON SUNDAY WE START TO SEE SOME CHANNELED VORTICITY ENERGY MOVE INTO
THE EASTERN UNITED STATES. MEANWHILE THE LOW-LEVEL RIDGE OVER THE
WESTERN ATLANTIC STARTS TO SHIFT EAST AS THE FLOW BACKS TO
SOUTHWESTERLY. AS LOW-LEVEL MOISTURE INCREASES...WEAK ISENTROPIC
ASCENT WILL DEVELOP ACROSS SOUTHEAST GA WITH SOME RAIN SHOWERS
POSSIBLE BY SUNDAY AFTERNOON. WE ADDED A SLIGHT CHANCE OF TSTMS
ACROSS FAR SOUTHERN AREAS BECAUSE A POCKET OF ELEVATED INSTABILITY
SHIFTS THROUGH DURING THIS TIME. LOW-LEVEL WARM ADVECTION WILL PUSH
HIGH TEMPS INTO THE LOWER TO MIDDLE 70S.
A BACKDOOR COLD FRONT WILL DROP INTO THE AREA SUNDAY NIGHT AND PUSH
OFFSHORE ON MONDAY. UPPER DYNAMICS ARE NOT VERY IMPRESSIVE
ACCOMPANYING THE FROPA SO WE ONLY HAVE 20-40 POPS SUNDAY NIGHT.
ON MONDAY...SLIGHTLY COOLER HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WHILE THE BACKDOOR FRONT SITS JUST SOUTH OF THE AREA.
EXTENSIVE CLOUD COVER WILL ALSO PERSIST THOUGH THE BEST RAIN CHANCES
WILL BE FAR SOUTH CLOSER TO THE FRONT. WE SHOW HIGH TEMPS IN THE
MID/UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PATTERN WILL MAINLY BE DOMINATED BY A LOBE OF THE
POLAR VORTEX MOVING INTO THE GREAT LAKES REGION LATE WEEK. MONDAY
NIGHT THROUGH WEDNESDAY THE UPPER PATTERN WILL BE TRENDING TOWARD A
BROAD TROUGH REGIME WITH A SERIES OF WEAK FRONTS AND LOW PRESSURE
WAVES AFFECTING THE FORECAST AREA. DUE TO LARGE UNCERTAINTIES IN
TIMING INDIVIDUAL FEATURES WE MAINTAINED A CONSERVATIVE FORECAST
WITH MAINLY SLIGHT CHANCES FOR SHOWERS AND HIGH TEMPS IN THE 60S.
A STRONG COLD FRONT WILL SWEEP THROUGH WEDNESDAY NIGHT... FOLLOWED
BY COOL CANADIAN HIGH PRESSURE THURSDAY AND FRIDAY. THIS WILL BRING
DRY CONDITIONS AND BELOW-NORMAL TEMPERATURES.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
AT KCHS...LOW CONFIDENCE FORECAST OVERNIGHT AS POTENTIAL FOR LOW CLOUDS
IS HIGH BUT TIMING AND AREAL EXTENT/TRANSLATION NEARLY IMPOSSIBLE
TO PIN DOWN THANKS TO AN INCREASING LOW LEVEL JET SCENARIO. WE CARRIED
ON SIMILAR TRENDS FROM THE 00Z TAF CYCLE WITH MVFR CONDITIONS BECOMING
LIKELY CLOSER TO DAYBREAK WITH LESSER CHANCES THE NEXT COUPLE OF HOURS.
CONVECTIVE RAINS INCLUDING CHANCES FOR TSTMS EXPECTED TO SWEEP THROUGH
THE COASTAL CORRIDOR BETWEEN LATE MORNING AND EARLY AFTERNOON WITH
CHANCES FOR A FEW TSTMS WITH GUSTY WINDS. CONDITIONS IMPROVING LATE
AFTERNOON WITH VFR CONDITIONS RETURNING.
AT KSAV...THE LAST TAF AMENDMENT INDICATES POSSIBLE MVFR
CONDITIONS DEVELOPING DUE TO REDUCED CEILINGS FROM SUNRISE TO MID
MORNING. MVFR CONDITIONS ARE THEN MAINTAINED IN SHOWERS THROUGH
ABOUT 19Z. GUSTY SW SURFACE WINDS ARE EXPECTED TO DEVELOP AFTER
MID MORNING AS BETTER MIXING COMMENCES AHEAD OF THE APPROACHING
COLD FRONT. SHOWERS AND A FEW TSTMS WILL PASS THROUGH THE MID TO
LATE MORNING THROUGH EARLY AFTERNOON IMPROVING CONDITIONS TO VFR
LATE AFTERNOON ONWARD.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE AT KSAV SATURDAY
NIGHT AND AT BOTH TERMINALS SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE VFR.
&&
.MARINE...
LITTLE TO NO REPORTS OF DENSE SEA FOG OVERNIGHT ALONG THE COAST WITH
SATELLITE IMAGERY ALSO NOT SUPPORTING OF FOG BASED LOW STRATUS OFF
THE COAST. THERE STILL IS A CHANCE FOR SEA FOG BUT GIVEN LATEST TRENDS
WE OPTED TO CANCEL MARINE FOG ADVISORIES AND JUST FORECAST PATCHY DENSE
FOG OVER THE WATERS THROUGH EARLY AFTERNOON WHEN RAIN CHANCES INCREASE
AND THE COLD FRONT NEARS.
OTHERWISE...NOT MUCH MIXING GOING ON OVER CHILLY SHELF WATERS AND IT
IS INTERESTING TO SEE WINDS GUSTS TO 20 KT AT TIMES AT CHARLESTON
AND SAVANNAH WHERE TEMPS HAVE WARMED TO THE UPPER 60S. TEMPS AT
GRAYS REEF NEAR 60 AND WINDS BELOW 10 KT ALL NIGHT WITH 2-3 FT
SEAS...QUITE THE STRONG MARINE INVERSION. SEAS WILL CONTINUE TO BUILD
OFFSHORE AND MAINTAINED A MARGINAL SCA FOR CHARLESTON COUNTY
WATERS MAINLY WELL EAST OF BULLS BAY. MOST NEAR SHORE WATERS TODAY
WILL SEE SW WINDS 15 KT OR SO AND SEAS 3-4 FT TOPS. THERE IS ALSO
A SCA FOR OUR OUTER GEORGIA WATERS WITH OCCASIONALLY GUSTY SW FLOW
AND SEAS 4-7 FT...HIGHEST NEAR THE WEST WALL OF THE GULF STREAM.
THE FRONT MOVES THROUGH THIS EVENING WITH WINDS SHIFTING W OR WNW
TONIGHT WITH COLD AIR ADVECTION MORE GRADUAL THAN SHARP...CONDITIONS
BELOW SCA CRITERIA.
MARINE WINDS/SEAS WILL BE RATHER LIGHT SATURDAY THROUGH SUNDAY
BEFORE A COLD FRONT DROPS INTO THE WATER SUNDAY NIGHT. WINDS WILL
INCREASE ALONG THE FRONT BUT THE STRONGER SURGE COMES MONDAY AS THE
FLOW BECOMES NE. CONDITIONS COULD FLIRT WITH ADVISORY LEVELS...
ESPECIALLY MONDAY NIGHT WHEN SEAS COME UP SOME.
THE NEXT SURGE COMES WEDNESDAY AND WEDNESDAY NIGHT BEHIND A STRONG
COLD FRONT. MODERATE CHANCES FOR SMALL CRAFT ADVISORIES WITH THE
MID-WEEK SYSTEM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ350-
374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
322 AM EST FRI FEB 21 2014
.SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
AVIATION...
06Z UPDATE...
LINE OF SHOWERS AND THUNDERSTORMS EXPECTED TO MOVE THROUGH THE
AREA OVERNIGHT...WITH DEGRADING CIGS AND VSBYS ACCOMPANYING THE
TSRA. HAVE TIMED THE SQUALL LINE THROUGH THE ATL AREA BY 10Z...AND
THE MCN AND AHN AREAS BY AROUND 12Z. S-SW GUSTY WINDS /15G25KT OR
SO/ WILL BECOME NW AT 13-15KT GUSTS TO 22-25KT BEHIND THE LINE.
EXPECT HIGH IFR OR LOW MVFR CIGS WITH THE POST-TSRA LIGHT
RAIN...WITH SLOW IMPROVEMENT THROUGH FRIDAY MORNING...AND VFR BY AFTERNOON.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 100 5 5 10
ATLANTA 61 39 66 43 / 80 5 5 10
BLAIRSVILLE 57 32 63 36 / 70 5 5 10
CARTERSVILLE 61 32 66 38 / 60 5 5 10
COLUMBUS 63 39 67 41 / 100 5 5 20
GAINESVILLE 62 38 65 40 / 100 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 40 5 5 10
PEACHTREE CITY 61 30 66 36 / 90 5 5 10
VIDALIA 68 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 9 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: CARROLL...CHATTAHOOCHEE...CLAYTON...COBB...
COWETA...DEKALB...DOUGLAS...FAYETTE...GWINNETT...HARALSON...
HARRIS...HEARD...HENRY...MARION...MERIWETHER...MUSCOGEE...NORTH
FULTON...PAULDING...PIKE...POLK...ROCKDALE...SCHLEY...SOUTH
FULTON...SPALDING...STEWART...SUMTER...TALBOT...TAYLOR...TROUP...
UPSON...WEBSTER.
TORNADO WATCH UNTIL 5 AM EST EARLY THIS MORNING FOR THE
FOLLOWING ZONES: BARTOW...CATOOSA...CHATTOOGA...CHEROKEE...
DADE...DAWSON...FANNIN...FLOYD...FORSYTH...GILMER...GORDON...
HALL...LUMPKIN...MURRAY...PICKENS...TOWNS...UNION...WALKER...
WHITE...WHITFIELD.
&&
$$
SHORT TERM...31
LONG TERM....39
AVIATION...31
Area Forecast Discussion
National Weather Service Lincoln IL
350 AM CST Fri Feb 21 2014
.DISCUSSION...
ISSUED 323 AM CST Fri Feb 21 2014
Dynamic storm system moved through the region yesterday and
overnight with the main cold front well out to the east and the
occluded low center over nrn Wisconsin this morning. A small wave
rippling around this morning in the wake of the cold front
bringing some light snow and may continue through the morning
hours. Other than that, forecast is mainly a slow chill beyond
today and tomorrow as another push of cold air comes to the
Midwest. As far as precipitation, several shortwaves are hinted in
the models, but timing is not very consistent. Best consistency is
for Monday/Monday night, with the chance for accumulating snow.
Beyond Monday, temperatures fall below normals in the extended for
next week. At this point the forecast in the extended is dry, but
as it is also increasingly NWrly flow, expect to eventually see a
couple of short waves creep into the forecast.
SHORT TERM...Today and tomorrow...
A short break in the frigid temperatures as the max temps will
climb above freezing heading into the weekend. Clearing this
morning should result in a sunny afternoon, but clouds redevelop
for tomorrow so partly cloudy skies will keep temps from
increasing too much over todays max. Tonight and tomorrow night, a
quick shot for snow across the northern tier of the CWA as
shortwaves ripple through in the wake of the exiting low. Both
shots at precip should result in less than a half of an inch of
accumulation.
LONG TERM...Sunday through Thursday...
Relatively dry but beyond the weekend the operational models are
shearing out some energy across the center of the country and
setting up a weak boundary in parallel flow. Agreement btwn GFS
and ECMWF for the existence of a Monday/Monday night system, with
major issues with the timing. At the end of the NAM run, but the
NAM is leaning into the same solution. Just another quick shot of snow
with a clipper-like system from the WNW. Colder air moving in as
well, as flow amplifies and Midwest sees northwesterly flow
reestablish Tuesday night/Wednesday. Temperatures from midweek on
drop below seasonal normals again.
HJS
&&
.AVIATION...
ISSUED 1139 PM CST Thu Feb 20 2014
Strong W/SW winds will continue through the overnight hours,
although they will not be quite as strong as earlier this
evening. Based on latest obs and 00z numeric guidance, have
lowered winds into the 15 to 20kt range with gusts to between 25
and 30kt. The strong/gusty winds will continue through Friday as
well, before subsiding to around 10kt by evening. Main aviation
challenge will be an area of MVFR clouds currently pushing
eastward across Iowa/northern Missouri. Satellite timing tools
bring these clouds into KSPI by 08z, then further east to KCMI
between 09z and 10z. HRRR does not have a good handle on the
clouds, but at least hints at ceilings overnight into early Friday
morning. Have therefore cleared skies from west to east between
12z and 14z.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
303 AM CST FRI FEB 21 2014
.DISCUSSION...
311 PM CST
THIS EVENING WILL SEE A QUICK TRANSITION FROM DENSE FOG TO BRIEFLY
HEAVY RAIN WITH THUNDERSTORMS...TO RAPIDLY FALLING TEMPERATURES AND
VERY STRONG WIND GUSTS. NOT SURE ABOUT EXACT TIMING OF BETTER
VISIBILITIES THIS EVENING...SO WILL MAINTAIN THE DENSE FOG ADVISORY
THROUGH 01Z BUT EXPECT SOUTHERN AREAS MAY CLEAR EARLIER THAN THAT.
VERY DENSE FOG WITH VISIBILITIES OF 1/4 MILE OR LESS IS BEING
REPORTED AT SEVERAL OBSERVATION SITES...AND LOWER VALUES ARE LIKELY
OUT THERE SOMEWHERE.
LATER THIS EVENING MODEL GUIDANCE AND UPSTREAM OBSERVATIONS BOTH
CONTINUE TO SUPPORT THE POTENTIAL FOR NON CONVECTIVE GUSTS IN
EXCESS OF 50 MPH FOR AT LEAST A WHILE AS THE COLD FRONT PUSHES
THROUGH.
LASTLY...THE FLOOD WATCH WAS ALLOWED TO EXPIRE AT 3 PM CST AFTER
THE BREAK IN THE AFTERNOON SHOWERS. SNOWMELT DOES CONTINUE AND
UPSTREAM STORMS MAY YET PRODUCE HEAVY RAIN...BUT THE STORMS SHOULD
BE VERY LOCALIZED AND RELATIVELY BRIEF. TEMPERATURES FALLING BELOW
FREEZING LATER THIS EVENING WOULD HELP TO FURTHER MITIGATE THE
DEGREE OF SNOWMELT.
LENNING
OVERNIGHT THROUGH THURSDAY...
AS COLDER AIR SPREADS ACROSS THE REGION BEHIND THE COLD FRONT...A
PERIOD OF LIGHT SNOW WILL BE POSSIBLE ESPECIALLY ACROSS THE
NORTHERN THIRD/HALF OF THE CWA. WITH ONLY A FEW HUNDREDTHS OF
QPF...SNOWFALL AMOUNTS WILL BE LIGHT A DUSTING TO PERHAPS A HALF
INCH. BUT WITH THE STRONG/GUSTY WINDS...ANY AMOUNT OF SNOWFALL
COULD CAUSE BLOWING AND DRIFTING SNOW. HAVE INCREASED POPS TO
LIKELY ACROSS THE NORTH OVERNIGHT BUT THESE MAY NEED TO GO HIGHER
AND PERHAPS BE EXTENDED INTO FRIDAY MORNING...ESPECIALLY FOR FAR
NORTHEAST IL. TEMPS WILL FALL THROUGH THE 20S AND COMBINED WITH
THE STRONG WINDS...WIND CHILLS IN THE SINGLE DIGITS ARE EXPECTED
BY FRIDAY MORNING.
A BRIEF PERIOD OF WEAK WARM AIR ADVECTION WILL OCCUR FRIDAY
AFTERNOON INTO FRIDAY EVENING AND THIS COMBINED WITH AT LEAST
PARTLY CLOUDY SKIES SHOULD HELP TEMPERATURES REBOUND INTO THE
LOWER/MID 30S NORTH TO UPPER 30S/NEAR 40 SOUTH. A COLD FRONT WILL
THEN MOVE ACROSS THE AREA FRIDAY NIGHT AND THERE REMAINS SOME
POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS AND HAVE INTRODUCED LOW
CHANCE POPS BACK INTO THE FORECAST FOR THIS TIME PERIOD. FLOW
REMAINS SOMEWHAT ZONAL SATURDAY WITH NO SIGNIFICANT COOLING BEHIND
THE FRONT...SO HIGHS SATURDAY COULD BE SIMILAR TO HIGHS ON FRIDAY.
BY SUNDAY MORNING...ANOTHER WEAK WAVE WILL QUICKLY MOVE ACROSS THE
REGION WITH A PERIOD OF LIGHT SNOW ASSOCIATED WITH IT. WHERE IT
MOVES/DEVELOPS REMAINS SOMEWHAT UNCERTAIN BUT THE NORTHERN EXTENT
OF IT MAY SPREAD ACROSS THE SOUTHERN CWA AND HAVE INCLUDED LOW
CHANCE POPS FOR THIS PERIOD.
FROM SUNDAY THROUGH THURSDAY...THE TREND WILL BE COLDER WITH HIGHS
ONLY IN THE 20S AND LOWS IN THE SINGLE DIGITS...AND THAT IS BEFORE
THE NEXT PUSH OF ARCTIC AIR ARRIVES WEDNESDAY/WEDNESDAY NIGHT. BY
THIS TIME...OVERNIGHT LOWS WILL LIKELY DROP INTO SINGLE DIGITS BELOW
ZERO WITH DAYTIME HIGHS BY THURSDAY MAYBE ONLY LOWER TEENS/SINGLE
DIGITS.
ONE OTHER CONCERN IN THE EXTENDED WOULD BE A CLIPPER SYSTEM TO
AFFECT THE REGION MONDAY AFTERNOON INTO MONDAY NIGHT. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE GFS/ECMWF FOR SEVERAL RUNS AND
SEEMS TO MOVE RIGHT ACROSS THE CWA BUT NOW IN A WEAKENING FORM. THIS
STILL APPEARS TO HAVE THE POTENTIAL TO PRODUCE A FEW INCHES OF
FLUFFY SNOW BUT HAVE ONLY BUMPED POPS INTO MID CHANCE RANGE FOR NOW.
CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* VERY GUSTY WESTERLY WINDS.
* MVFR CIGS IMPROVING TO VFR LATE FRIDAY MORNING/EARLY AFTERNOON.
* CHANCE FOR SOME ADDITIONAL LIGHT SNOW SHOWERS EARLY TO MID
FRIDAY MORNING...WITH BLOWING SNOW.
BMD
//DISCUSSION...UPDATED 06Z...
DEEP AREA OF LOW PRESSURE WILL CONTINUE TO LIFT ACROSS WISCONSIN
OVERNIGHT WITH A TIGHT PRESSURE GRADIENT AND STRONG PRESSURE RISES
ACROSS NORTHERN ILLINOIS RESULTING IN STRONG WESTERLY WINDS. WIND
ARE EXPECTED TO CONTINUE TO GUST IN THE MID TO UPPER 30 KT RANGE
OVERNIGHT THROUGH FRIDAY AFTERNOON...THEN SHOULD BEGIN TO TAPER
LATE AFTERNOON INTO THE EVENING AS THE GRADIENT SLACKENS.
CIGS ACROSS THE REGION ARE GENERALLY 015-025 TONIGHT AND EXPECT
THESE LEVELS TO PERSIST OVERNIGHT. ANOTHER WAVE CURRENTLY OVER
IOWA WILL MOVE ACROSS THE TERMINALS EARLY TO MID MORNING BRING
ADDITIONAL LIGHT SNOW SHOWERS. MOISTURE IS FAIRLY SHALLOW THOUGH
AND SOME MODELS MAINTAIN DRY CONDITIONS IN THE MORNING. WILL HAVE
TO MONITOR UPSTREAM TRENDS AND MAY BE ABLE TO PULL MENTION OF
SNOW/BLOWING SNOW IF THIS OCCURS. OTHERWISE...GIVEN THE STRONG
WINDS...EXPECT EVEN LIGHT SNOW TO BLOW AROUND RESULTING IN MORE
SIGNIFICANT REDUCTIONS IN VISIBILITY THAN OTHERWISE WOULD BE
EXPECTED.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE IN WIND DIRECTION...MEDIUM-HIGH CONFIDENCE IN
SPEED.
* MEDIUM-HIGH CONFIDENCE IN CIG TRENDS...MEDIUM IN TIMING
IMPROVEMENT TO VFR.
* LOW CONFIDENCE IN HOW AREAS OF SNOW WILL EVOLVE OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...SLIGHT CHANCE OF LIGHT SNOW DURING THE AFTERNOON AND
NIGHT OTHERWISE VFR.
TUESDAY...VFR.
WEDNESDAY...VFR.
ED F
&&
.MARINE...
302 AM CST
STRONG LOW PRESSURE LIES OVER WISCONSIN EARLY THIS MORNING AND WILL
LIFT NORTH ACROSS ONTARIO TO JAMES BAY BY LATE TONIGHT.
MEANWHILE...A TIGHT PRESSURE GRADIENT WILL RESULT IN STRONG GALES
AND STORM FORCE WINDS AT TIMES ACROSS LAKE MICHIGAN THROUGH THIS
AFTERNOON. WILL LEAVE THE CURRENT TIMING IN PLACE FOR THE STORM
WARNING...THOUGH LATEST PROJECTIONS INDICATE THAT IT MAY BE
CANCELED EARLY. EITHER WAY...A GALE WARNING WILL BE NEEDED TO
REPLACE THE STORM WARNING FOR A PERIOD LATE THIS AFTERNOON INTO
THE EARLY OVERNIGHT HOURS. WINDS SHOULD FINALLY DIMINISH BELOW
GALES LATE TONIGHT BUT WILL REMAIN AROUND 30 KT THROUGH THE
REMAINDER OF THE WEEKEND. A BROAD RIDGE OF HIGH PRESSURE WILL
BUILD FROM THE NORTHERN PLAINS INTO THE OHIO VALLEY AND REMAIN
ANCHORED FOR MUCH OF THE UPCOMING WEEK...LEAVING LAKE MICHIGAN
WITH PERSISTENT MODERATE WEST TO NORTHWEST WINDS NEXT WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-
ILZ032-ILZ033-ILZ039 UNTIL 3 PM FRIDAY.
IN...WIND ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 3 PM
FRIDAY.
LM...STORM WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM FRIDAY.
STORM WARNING...NEARSHORE WATERS UNTIL
4 AM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1139 PM CST Thu Feb 20 2014
.DISCUSSION...
ISSUED 847 PM CST Thu Feb 20 2014
Cold front and associated convection has now pushed well to the
east into Indiana, leaving behind windy and cooler conditions
across central Illinois. Latest obs generally show winds in the 25
to 35 mph range, with gusts occasionally over 40 mph. Will
continue with the High Wind Warning at this time, but this may
need to be canceled early as upstream winds across Missouri have
weakened even further. Made some minor adjustments to hourly temp
grids to account for the colder air spilling into the region, but
changes do not effect the going forecast. Therefore no zone update
is needed at this time.
Barnes
&&
.AVIATION...
ISSUED 1139 PM CST Thu Feb 20 2014
Strong W/SW winds will continue through the overnight hours,
although they will not be quite as strong as earlier this
evening. Based on latest obs and 00z numeric guidance, have
lowered winds into the 15 to 20kt range with gusts to between 25
and 30kt. The strong/gusty winds will continue through Friday as
well, before subsiding to around 10kt by evening. Main aviation
challenge will be an area of MVFR clouds currently pushing
eastward across Iowa/northern Missouri. Satellite timing tools
bring these clouds into KSPI by 08z, then further east to KCMI
between 09z and 10z. HRRR does not have a good handle on the
clouds, but at least hints at ceilings overnight into early Friday
morning. Have therefore cleared skies from west to east between
12z and 14z.
Barnes
&&
.PREV DISCUSSION...
ISSUED 320 PM CST Thu Feb 20 2014
Short term issues revolve around a rapidly deepening low pressure
system passing across far NW IL this afternoon, with a cold front
racing across IL and into Indiana by 7 pm. Severe weather
potential will progress east along and south of the warm front.
Areas of very dense fog should dissipate behind the cold front as
well.
Very strong winds will develop as pressure rises reach 12mb per 3
hours. Wind speeds of 30-40 mph and gusts over 55 mph will develop
shortly after the cold front passes. Flooding is already occurring
across Knox and Stark counties where 2-2.5" of rain already fell
earlier today. More rain from the line of thunderstorms could
aggravate the flooding.
Beyond the very busy short term, we have various short waves
expected to move across IL between Friday night and Monday night.
With the colder air also arriving this weekend, most of any
precipitation that does develop should fall as snow. The models
are producing widely varying solutions as to amount and coverage
of any precip during that time, but we wanted to at least
acknowledge the potential for precip due to at least 2 models
showing some precipitation produced by each wave.
SHORT TERM...Tonight through Sunday.
A line of storms will race across IL just ahead of the cold front.
Forward motion of the storms is being measured at 60 mph, with a
low level jet of 70 kts just above the LCL. Storms are moving from
to the N-NE towards areas with snow cover and more stable air near
the ground. We expect to see localized damaging winds from the
storm gust fronts in areas along and south of the warm front,
which generally extends from Galesburg to Bloomington at this
point. Isolated tornadoes could develop as wind shear rapidly
increases just ahead of the cold front.
As storms move farther north over snow covered areas, storms should
begin to lose the ability to blast damaging winds through the
stable low level airmass to the ground. The severe thunderstorm
watch goes until 6 pm for out SW counties, but an additional watch
will likely be needed farther east and south of the warm front as
the cold front moves across IL.
Dense fog has caused travel hazards for areas north of Rushville
to Lincoln to Bloomington, and a dense fog advisory will go
through 6 pm.
Shortly behind the cold front, very strong pressure rises will
produce very strong winds for several hours, with the strongest
gusts possibly as high as 60 mph in the first 3-4 hours behind the
front. Pressure rises diminish somewhat later this evening, but
sustained winds will likely remain around 30 mph gusting to 40 mph
at times until midnight. We may be able to remove some of the
wind warning headline a little before 3 am as conditions warrant.
A band of light rain or snow may move into our west-northwestern
counties this evening through just after midnight, but little to
no snow accumulation is expected.
The axis of coldest air behind the cold front will pass across our
forecast area around 12z/6am Friday morning. Clouds will begin to
clear out of our SW areas around that time, but lows should still
remain in the mid 20s north and upper 20 south. Warming occurs
through the day on Friday, as 850mb temps climb from -8C or -9C at 6
am to zero to -2C at 6 pm. West-southwest winds will remain brisk
and help to push high temps into the 40s across the board.
The first shortwave that could produce some light snow is forecast
to arrive Friday night. The GFS and Canadian have been
consistently showing that feature and a dusting to a half inch of
snow across the northern counties. The 12z Canadian did back off a
little on the QPF, but the 12z ECMWF has started pointing towards
forcing for precip during that time over that area as well.
The airmass cools down for Saturday, as high pressure builds into
IL from the NW. The GFS and Canadian once again team up on a
shortwave for Sunday, producing 0.5" to 1" of snow across our W
and N counties. The NAM indicates some snow for our southeastern
counties Sunday afternoon, while the ECMWF is not resolving that
feature as well.
More noticeably cooler highs are forecast for Sunday as readings
top out about 10-12F degrees colder than Saturday.
LONG TERM...Monday through Thursday.
The third shortwave is projected to arrive later Monday morning or
Monday afternoon. There is some agreement on this by the GFS,
Canadian, and ECMWF. With 3 models in general agreement, we
increased PoPs into the chance category across the north, for
another 0.5 to 1" of snow through early Monday evening.
A stronger push of cold air will arrive behind that wave, as 850mb
temps drop to -16C to -18C by Tuesday evening. Lows should reach
into the single digits above zero north of Peoria to Bloomington
Tues night, with single digits N of I-70 Wed night. The coldest
highs this week look to be on Thursday as readings remain in the
teens north of a line from Rushville to Champaign.
Light snow may return late next Thursday afternoon and Thursday
night as yet another shortwave pushes into the area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 3 AM CST Friday FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION...CORRECTED
NWS BALTIMORE MD/WASHINGTON DC
456 AM EST FRI FEB 21 2014
.SYNOPSIS...
A WARM FRONT IS POSITIONED ACROSS SOUTHERN VIRGINIA WHILE A COLD FRONT
STRETCHES FROM OHIO TO ALABAMA. THE COLD FRONT WILL MOVE THROUGH
THE MID ATLANTIC BY EARLY AFTERNOON. HIGH PRESSURE WILL RETURN
OVER THE WEEKEND. UNSETTLED WEATHER IS POSSIBLE TUESDAY.
&&
.NEAR TERM /TODAY/...
QUITE A CHANGEABLE PD IN THE MID ATLC - CLOSE TO 1.5 FT OF SNOW
ACROSS MUCH OF THE AREA A WK AGO HAS BEEN LARGELY MELTED AWAY. A
CHECK OF SNOW ON THE GRND RECORDS (SOLELY IAD) SHOW IT IS INDEED
HARD TO KEEP SNOWPACK ON GRND VERY LONG - IN 42 YRS OF RECORDS
MORE THAN 1" OF SNOW ON GRND HAS ONLY RMND ON GRND LONGER THAN ONE
WK 25 TIMES. RECORD LENGTH OF TIME WAS AT THE END OF 1969 - 23 DAYS.
PRSNT SFC ANLYS/OBS SHOW A WARM FNT ALONG THE NC/VA BRDR CURVING
UP INTO SERN VA. IN SOME LOCATIONS THERE`S A 15-20 TEMP DIFFERENCE
OVR THE COURSE OF 20 MILES. AND TO OUR W IS A FAST MOVG CD FNT -
THRU 3 AM CRW WAS ISSUING WRNGS ON IT: THEIR OFFICE RCVD A GUST TO
60 MPH AT 220 AM.
THE CD FNT WL BE PUSHING INTO THE APLCHNS ARND 14Z...QUICKLY
REACHING THE BAY ABT 5 HRS LATER. QUSTN THEN BECOMES HOW MUCH OF
THE CD WEDGE ON THE N SIDE OF THE WARM FNT WL BE ERODED AWAY B4
THE CD FNT MOVES IN. THIS IN TURN MAKES FOR AN XTRMLY CHALLENGING
TEMP FCST. USED HRRR 2M TEMP FIELD AS A GUIDE..AS WELL AS PAST
HISTORY ON SYNTOPIC SITUATIONS SUCH AS THIS: SUSPECT THAT THE
COLDER WEDGE WL NOT BE PUSHED OUT W/ THE XCPTN OF LWR SRN
MD...WHERE IT MAY HAPPEN FOR AN HOUR OR TWO B4 THE CD FNT MOVES THRU.
NEXT CONCERN IS SVR/WIND THREATS. THE TIME OF DAY THE FNT IS PASSING
THRU IS NOT OPTIMAL FOR CNVCTV DVLPMNT...AND LTNG ACTVTY HAS BEEN
DIMINISHING AND TRACKING FURTHER S AS THE NGT PROGRESSES. BUT AT
THIS TIME OF YR LTNG IS NOT THE ONLY CONCERN...AS IS WITNESSED BY
THE WRNGS/OBS BEING XPRNCD IN W.V. LOW TOPPED FAST MOVG STORMS CAN
BRING STRONG WINDS TO THE SFC...AND IAD VWP IS SHOWING WINDS INXS
OF 70 KT AT FL 040. WE HV ISSUED A WIND ADVSRY FOR THE HIGHER
ELEVS BECAUSE OF THIS.
TEMP FCST - CONFIDENCE IS NOT AT ITS HIGHEST...BUT MUCH OF THE
AREA SHOULD SEE THE L50S FOR HIGHS...LWR SRN MD MAY END UP ABT TEN
DEGS WRMR B4 THE CD FNT PUSHES THRU.
&&
.SHORT TERM /TONIGHT/...
TNGT IS A LESS CHALLENGING FCST AS HIGH PRES MOVES IN BEHIND THE
FNT. LOWS IN THE 20S W OF THE BLUE RDG...30S ELSEWHERE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
ZONAL FLOW ALOFT MOVES IN THIS WEEKEND BEHIND TODAY/S COLD FRONTAL
PASSAGE. SATURDAY LOOKS TO BE A MILD DAY WITH ZONAL FLOW
ALOFT...PLENTY OF SUNSHINE AND A SOUTHWEST WIND IN THE LOW LEVELS.
THIS WILL BOOST TEMPERATURES WELL INTO THE 50S AND PERHAPS ABOVE 60
IN SOME AREAS SATURDAY AFTERNOON.
SAT NGT THRU THU/...
WE EXPECT INCREASING CLOUDS SATURDAY NIGHT INTO SUNDAY AS A
SHORTWAVE APPROACHES. AT THE SURFACE...A COLD FRONTAL PASSAGE WILL
OCCUR DURING THE DAY SUNDAY. ANOTHER SHORTWAVE ON THE HEELS OF THE
FRONT MAY BRING A CHANCE OF SNOW SHOWERS SUNDAY NIGHT NEAR THE MASON
DIXON LINE AND OVER THE POTOMAC HIGHLANDS.
CANADIAN HIGH PRESSURE THEN BUILDS IN FOR MONDAY WITH A COLDER AIR
MASS TAKING HOLD OVER THE MID ATLANTIC. THIS COLDER AIR MASS WILL
NOT ONLY STICK AROUND THROUGH MID-WEEK BUT WILL LIKELY BE REINFORCED
THROUGH THIS TIME.
THERE IS STILL THE POTENTIAL FOR SOME WINTRY PRECIPITATION IN THE
TUESDAY TO WEDNESDAY TIME FRAME...BUT UNCERTAINTY REMAINS REGARDING
THE DETAILS INCLUDING TIMING AND STRENGTH. KEPT LOW CHANCE POPS IN
THE FORECAST.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
CONDS WL BE DIMINISHING RAPIDLY THIS MRNG AS A FAST MOVG CD FNT
ROLLS THRU THE MID ATLC AREA. IAD VWP IS SHOWING 70 KT AT FL
040...LLWX WL BE XPRNCD BY AIRCRAFT THIS MRNG. HVY RW DURG THE
11-18Z TIME WL CAUSE DIMINISHED CIGS AND VSBYS.
VFR CONDS TNGT.
SATURDAY INTO EARLY NEXT WEEK...NO SIGNIFICANT WX EXPECTED WITH A
WEAK COLD FRONT SUNDAY AND THEN HIGH PRESSURE MONDAY. NEXT STORM
APPROACHES WITH A CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
AN SCA IS IN EFFECT FOR ALL WATERS TDA. SMW`S MAY BE NEEDED...
ESPECIALLY IN LWR TIDAL PTMC AND CHES BAY S OF DRUM PT DURG LATE
MRNG/ERLY AFTN.
HIGH PRESSURE BUILDS IN SATURDAY...THEN A COLD FRONT MOVES THROUGH
SUNDAY. SCA IS LIKELY ON MONDAY IN NORTHWEST WINDS BEHIND THE
FRONT.
&&
.HYDROLOGY...
WE`VE LOST UP TO ONE INCH OF SNOW WATER IN THE PAST TWO DAYS AREA
WIDE. SNOW WATER EQUIVALENT VALUES ARE STILL QUITE HIGH IN THE FAR
POTOMAC HIGHLANDS...BUT THE HIGHEST VALUES ARE MAINLY UPSTREAM OF
JENNINGS RANDOLPH AND SAVAGE RIVER LAKES...AND THE OVERALL VALUES
ARE MUCH LESS THAN OBSERVED IN PREVIOUS SNOWMELT FLOOD EVENTS.
THERE WILL BE MORE MELT TODAY. THAT WILL BE ENOUGH TO CAUSE RIVER
RISES AND THESE ARE REFLECTED IN THE CURRENT RIVER FORECASTS.
RIGHT NOW NONE OF THE FORECASTS RISE TO FLOOD STAGE...BUT IF
SNOWMELT OR RAIN AMOUNTS ON TODAY EXCEED THE CURRENT PROJECTIONS...
SOME MINOR FLOODING WILL BE POSSIBLE... PARTICULARLY ON SMALLER
CREEKS AND STREAMS AND OUR USUAL FIRST-TO-FLOOD SPOTS AMONG THE
RIVER FORECAST POINTS.
THE GRADUAL MELT RESUMES OVER THE WEEKEND...WITH FREEZES EACH NIGHT
AND NO PRECIPITATION EXPECTED. COLDER WEATHER ARRIVES EARLY NEXT
WEEK...SIGNIFICANTLY DECREASING OR STOPPING THE MELT FOR AWHILE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR MDZ501.
VA...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR VAZ025>027-029-
036>039-503-504.
WV...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR WVZ050-055-
501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ530-
531-535-536-538-539.
&&
$$
PRODUCTS,,,WOODY!/BPP
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
348 AM EST FRI FEB 21 2014
.SYNOPSIS...
A WARM FRONT IS POSITIONED ACROSS SOUTHERN VIRGINIA WHILE A COLD FRONT
STRETCHES FROM OHIO TO ALABAMA. THE COLD FRONT WILL MOVE THROUGH
THE MID ATLANTIC BY EARLY AFTERNOON. HIGH PRESSURE WILL RETURN
OVER THE WEEKEND. UNSETTLED WEATHER IS POSSIBLE TUESDAY.
&&
.NEAR TERM /TODAY/...
QUITE A CHANGEABLE PD IN THE MID ATLC - CLOSE TO 1.5 FT OF SNOW
ACROSS MUCH OF THE AREA A WK AGO HAS BEEN LARGELY MELTED AWAY. A
CHECK OF SNOW ON THE GRND RECORDS (SOLELY IAD) SHOW IT IS INDEED
HARD TO KEEP SNOWPACK ON GRND VERY LONG - IN 42 YRS OF RECORDS
MORE THAN 1" OF SNOW ON GRND HAS ONLY RMND ON GRND LONGER THAN ONE
WK 25 TIMES. RECORD LENGTH OF TIME WAS AT THE END OF 1969 - 23 DAYS.
PRSNT SFC ANLYS/OBS SHOW A WARM FNT ALONG THE NC/VA BRDR. THE FNT
HAS ACTUALLY PUSHED INTO SERN VA - IN SOME LOCATIONS THERE`S A
15-20 TEMP DIFFERENCE OVR THE COURSE OF 20 MILES. AND TO OUR W IS
A FAST MOVG CD FNT - CRW HAS BEEN ISSUING WRNGS ON IT SINCE MDNGT:
THEIR OFFICE RCVD A GUST TO 60 MPH AT 220 AM.
THE CD FNT WL BE PUSHING INTO THE APLCHNS ARND 14Z...QUICKLY
REACHING THE BAY ABT 5 HRS LATER. QUSTN THEN BECOMES HOW MUCH OF
THE CD WEDGE ON THE N SIDE OF THE WARM FNT WL BE ERODED AWAY B4
THE CD FNT MOVES IN. THIS IN TURN MAKES FOR AN XTRMLY CHALLENGING
TEMP FCST. USED HRRR 2M TEMP FIELD AS A GUIDE..AS WELL AS PAST
HISTORY ON SYNTOPIC SITUATIONS SUCH AS THIS: SUSPECT THAT THE
COLDER WEDGE WL NOT BE PUSHED OUT W/ THE XCPTN OF LWR SRN
MD...WHERE IT MAY HAPPEN FOR AN HOUR OR TWO B4 THE CD FNT MOVES THRU.
NEXT CONCERN IS SVR/WIND THREATS. THE TIME OF DAY THE FNT IS PASSING
THRU IS NOT OPTIMAL FOR CNVCTV DVLPMNT...AND LTNG RMNS OVR NC AND
PTS S. BUT AT THIS TIME OF YR LTNG IS NOT THE ONLY CONCERN...AS IS
WITNESSED BY THE WRNGS/OBS BEING XPRNCD IN W.V. LOW TOPPED FAST
MOVG STORMS CAN BRING STRONG WINDS TO THE SFC...AND IAD VWP IS
SHOWING WINDS INXS OF 70 KT AT FL 040. WE HV ISSUED A WIND ADSRVY
FOR THE HIGHER ELEVS BECAUSE OF THIS.
TEMP FCST - CONFIDENCE IS NOT AT ITS HIGHEST...BUT MUCH OF THE
AREA SHOULD SEE THE L50S FOR HIGHS...LWR SRN MD MAY END UP ABT TEN
DEGS WRMR B4 THE CD FNT PUSHES THRU.
&&
.SHORT TERM /TONIGHT/...
TNGT IS A LESS CHALLENGING FCST AS HIGH PRES MOVES IN BEHIND THE
FNT. LOWS IN THE 20S W OF THE BLUE RDG...30S ELSEWHERE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
ZONAL FLOW ALOFT MOVES IN THIS WEEKEND BEHIND TODAY/S COLD FRONTAL
PASSAGE. SATURDAY LOOKS TO BE A MILD DAY WITH ZONAL FLOW
ALOFT...PLENTY OF SUNSHINE AND A SOUTHWEST WIND IN THE LOW LEVELS.
THIS WILL BOOST TEMPERATURES WELL INTO THE 50S AND PERHAPS ABOVE 60
IN SOME AREAS SATURDAY AFTERNOON.
SAT NGT THRU THU/...
WE EXPECT INCREASING CLOUDS SATURDAY NIGHT INTO SUNDAY AS A
SHORTWAVE APPROACHES. AT THE SURFACE...A COLD FRONTAL PASSAGE WILL
OCCUR DURING THE DAY SUNDAY. ANOTHER SHORTWAVE ON THE HEELS OF THE
FRONT MAY BRING A CHANCE OF SNOW SHOWERS SUNDAY NIGHT NEAR THE MASON
DIXON LINE AND OVER THE POTOMAC HIGHLANDS.
CANADIAN HIGH PRESSURE THEN BUILDS IN FOR MONDAY WITH A COLDER AIR
MASS TAKING HOLD OVER THE MID ATLANTIC. THIS COLDER AIR MASS WILL
NOT ONLY STICK AROUND THROUGH MID-WEEK BUT WILL LIKELY BE REINFORCED
THROUGH THIS TIME.
THERE IS STILL THE POTENTIAL FOR SOME WINTRY PRECIPITATION IN THE
TUESDAY TO WEDNESDAY TIME FRAME...BUT UNCERTAINTY REMAINS REGARDING
THE DETAILS INCLUDING TIMING AND STRENGTH. KEPT LOW CHANCE POPS IN
THE FORECAST.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
CONDS WL BE DIMINISHING RAPIDLY THIS MRNG AS A FAST MOVG CD FNT
ROLLS THRU THE MID ATLC AREA. IAD VWP IS SHOWING 70 KT AT FL
040...LLWX WL BE XPRNCD BY AIRCRAFT THIS MRNG. HVY RW DURG THE
11-18Z TIME WL CAUSE DIMINISHED CIGS AND VSBYS.
VFR CONDS TNGT.
SATURDAY INTO EARLY NEXT WEEK...NO SIGNIFICANT WX EXPECTED WITH A
WEAK COLD FRONT SUNDAY AND THEN HIGH PRESSURE MONDAY. NEXT STORM
APPROACHES WITH A CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
AN SCA IS IN EFFECT FOR ALL WATERS TDA. SMW`S MAY BE NEEDED...
ESPECIALLY IN LWR TIDAL PTMC AND CHES BAY S OF DRUM PT DURG LATE
MRNG/ERLY AFTN.
HIGH PRESSURE BUILDS IN SATURDAY...THEN A COLD FRONT MOVES THROUGH
SUNDAY. SCA IS LIKELY ON MONDAY IN NORTHWEST WINDS BEHIND THE
FRONT.
&&
.HYDROLOGY...
WE`VE LOST UP TO ONE INCH OF SNOW WATER IN THE PAST TWO DAYS AREA
WIDE. SNOW WATER EQUIVALENT VALUES ARE STILL QUITE HIGH IN THE FAR
POTOMAC HIGHLANDS...BUT THE HIGHEST VALUES ARE MAINLY UPSTREAM OF
JENNINGS RANDOLPH AND SAVAGE RIVER LAKES...AND THE OVERALL VALUES
ARE MUCH LESS THAN OBSERVED IN PREVIOUS SNOWMELT FLOOD EVENTS.
THERE WILL BE MORE MELT TODAY. THAT WILL BE ENOUGH TO CAUSE RIVER
RISES AND THESE ARE REFLECTED IN THE CURRENT RIVER FORECASTS.
RIGHT NOW NONE OF THE FORECASTS RISE TO FLOOD STAGE...BUT IF
SNOWMELT OR RAIN AMOUNTS ON TODAY EXCEED THE CURRENT PROJECTIONS...
SOME MINOR FLOODING WILL BE POSSIBLE... PARTICULARLY ON SMALLER
CREEKS AND STREAMS AND OUR USUAL FIRST-TO-FLOOD SPOTS AMONG THE
RIVER FORECAST POINTS.
THE GRADUAL MELT RESUMES OVER THE WEEKEND...WITH FREEZES EACH NIGHT
AND NO PRECIPITATION EXPECTED. COLDER WEATHER ARRIVES EARLY NEXT
WEEK...SIGNIFICANTLY DECREASING OR STOPPING THE MELT FOR AWHILE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR MDZ501.
VA...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR VAZ025>027-029-
036>039-503-504.
WV...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR WVZ050-055-
501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ530-
531-535-536-538-539.
&&
$$
PRODUCTS,,,WOODY!/BPP
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1204 AM EST FRI FEB 21 2014
.SYNOPSIS...
A WARM FRONT LIFTS NORTH OF THE REGION THIS MORNING. A COLD FRONT
CROSSES THE AREA LATER TODAY. HIGH PRESSURE AND DRIER CONDITIONS
RETURN FOR THE WEEKEND.
&&
.NEAR TERM /OVERNIGHT/...
LATEST MSAS SHOWING WARM FRONT LIFTG NORTH ACROSS THE AREA ATTM.
QUITE A TEMP CONTRAST ACROSS THE AREA AT MIDNIGHT. CRNTLY 41 AT
LKU RANGING TO 66 AT NTU. WILL DO A QUICK UPDATE TO ACCOUNT FOR
THE 10+ DEGREE TEMP / DP TEMP RISE BEHIND WARM FRONT PAST FEW
HOURS. WILL CALL THE MIDNIGHT OBS THE MIN TEMP ACROSS THE NORTH
WITH RISING TMPS OVERNIGHT...OTW STDY 60-65. NAM12 SEEMS TO BEST
DEPICT THE TMP CHANGES.
PVS DSCN:
VRB CLDS TO MCLDY ACRS THE FA. WARM FRONT RMNS SLO TO MOVE N
THROUGH THE RGN THIS EVE...WILL DO SO...W/ LAST PLACES TO LOSE THE
LO LVL WEDGE WNW OF RIC. MDLS DIFFER AS TO LO CIGS OR DEVELOPMENT.
WILL INCLUDE AREAS OF FG OVR PORTIONS OF THE WTRS OVRNGT AS THE
WARM AIR PUSHES NWD OVR THE COLDER BAY/OCN WTRS...OTRW CONTG W/
MNLY MCLDY SKY COVER. LO TEMPS ABT REACHED IN MOST PLACES...ESP
SRN VA/NE NC. A RISE IN TEMPS XPCD IN ALL AREAS AS WARM FRONT
CONTS N.
HAVE CUTBACK POPS TO 20% AFTR 09Z WEST OF I95 FOR SLOWER ARRIVAL
TO PCPN. DRY ELSEWHERE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
AS OF 0430Z...WINDS INCREASING OVER THE SOUTHERN END OF THE BAY AS
THE WARM FRONT MOVES THROUGH. SCA CONDITIONS WILL DEVELOP ACROSS
THE WATERS DURING THE EARLY MORNING HOURS. WINDS OF SCA STRENGTH
MAY BE INTERMITTENT DURING THE OVERNIGHT DUE TO THE COLD WATER
TEMPERATURE BUT WILL INCREASE TO A MORE SOLID SCA DURING THE DAY
FRIDAY. THE WINDS SHOULD EASILY TO SCA THRESHOLDS DURING THE DAY
FRIDAY.
FROM PREVIOUS DISCUSSION...
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG
COLD FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT
TONIGHT. WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE
STRONGEST WINDS ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND
THE TIGHT GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND
20-30 KT OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO
FRI BEFORE THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON.
SHOWERS AND THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH
MAY PRODUCE STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT
CROSSES THE WATERS AND WINDS BACK TO THE NW...ANTICIPATE A QUICK
SURGE POST FRONTAL BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH
PRESSURE BUILDS IN FROM THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE
TO 4 FT AROUND MIDDAY FRIDAY ON THE BAY. MEANWHILE...SEAS WILL
BUILD TO 5-6 FT ON THE SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE
NORTHERN COASTAL WATERS. HEADLINES ARE IN EFFECT FOR ALL WATERS
FROM AFTER MIDNIGHT TONIGHT THROUGH 4PM FRIDAY. RIVERS DROP OFF
FIRST BEFORE THE BAY AT 6PM AND THE NRN COASTAL WATERS AT MIDNIGHT
FRI NIGHT. HIGH PRESSURE REMAINS OVER THE WATERS THROUGH THE
WEEKEND BEFORE A CLIPPER FRONT CROSSES THE WATERS SUNDAY NIGHT-
MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
ANZ650-652-654.
SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR ANZ656-658.
&&
$$
SYNOPSIS...MPR
NEAR TERM...ALB/MPR
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM/LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1154 PM EST THU FEB 20 2014
.SYNOPSIS...
A WARM FRONT WILL NORTH OF THE REGION OVERNIGHT. A COLD FRONT
CROSSES THE MID ATLANTIC REGION ON FRIDAY. HIGH PRESSURE AND
DRIER CONDITIONS RETURN TO THE REGION DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
VRB CLDS TO MCLDY ACRS THE FA. WARM FRONT RMNS SLO TO MOVE N
THROUGH THE RGN THIS EVE...WILL DO SO...W/ LAST PLACES TO LOSE THE
LO LVL WEDGE WNW OF RIC. MDLS DIFFER AS TO LO CIGS OR DEVELOPMENT.
WILL INCLUDE AREAS OF FG OVR PORTIONS OF THE WTRS OVRNGT AS THE
WARM AIR PUSHES NWD OVR THE COLDER BAY/OCN WTRS...OTRW CONTG W/
MNLY MCLDY SKY COVER. LO TEMPS ABT REACHED IN MOST PLACES...ESP
SRN VA/NE NC. A RISE IN TEMPS XPCD IN ALL AREAS AS WARM FRONT
CONTS N.
HAVE CUTBACK POPS TO 20-30% (LATE TNGT) ALG/W OF I 95 FOR SLOWER
ARRIVAL TO PCPN. ELSW...POPS AOB 10%.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
AS OF 0430Z...WINDS INCREASING OVER THE SOUTHERN END OF THE BAY AS
THE WARM FRONT MOVES THROUGH. SCA CONDITIONS WILL DEVELOP ACROSS
THE WATERS DURING THE EARLY MORNING HOURS. WINDS OF SCA STRENGTH
MAY BE INTERMITTENT DURING THE OVERNIGHT DUE TO THE COLD WATER
TEMPERATURE BUT WILL INCREASE TO A MORE SOLID SCA DURING THE DAY
FRIDAY. THE WINDS SHOULD EASILY TO SCA THRESHOLDS DURING THE DAY
FRIDAY.
FROM PREVIOUS DISCUSSION...
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG
COLD FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT
TONIGHT. WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE
STRONGEST WINDS ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND
THE TIGHT GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND
20-30 KT OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO
FRI BEFORE THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON.
SHOWERS AND THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH
MAY PRODUCE STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT
CROSSES THE WATERS AND WINDS BACK TO THE NW...ANTICIPATE A QUICK
SURGE POST FRONTAL BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH
PRESSURE BUILDS IN FROM THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE
TO 4 FT AROUND MIDDAY FRIDAY ON THE BAY. MEANWHILE...SEAS WILL
BUILD TO 5-6 FT ON THE SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE
NORTHERN COASTAL WATERS. HEADLINES ARE IN EFFECT FOR ALL WATERS
FROM AFTER MIDNIGHT TONIGHT THROUGH 4PM FRIDAY. RIVERS DROP OFF
FIRST BEFORE THE BAY AT 6PM AND THE NRN COASTAL WATERS AT MIDNIGHT
FRI NIGHT. HIGH PRESSURE REMAINS OVER THE WATERS THROUGH THE
WEEKEND BEFORE A CLIPPER FRONT CROSSES THE WATERS SUNDAY NIGHT-
MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
ANZ650-652-654.
SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR ANZ656-658.
&&
$$
SYNOPSIS...ALB/BMD
NEAR TERM...ALB/BMD
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM/LSA
AREA FORECAST DISCUSSION
NWS NORMAN OK
404 AM CST FRI FEB 21 2014
.DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
&&
.FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 39 66 42 / 0 0 0 0
HOBART OK 68 38 70 41 / 0 0 0 0
WICHITA FALLS TX 71 43 76 47 / 0 0 0 0
GAGE OK 64 21 63 34 / 0 0 0 0
PONCA CITY OK 63 35 60 36 / 0 0 0 10
DURANT OK 65 44 70 52 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR OKZ005>030-033>040-044-045.
TX...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR TXZ083>090.
&&
$$
03/17
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
214 AM CST FRI FEB 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CST FRI FEB 21 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM ALASKA DOWN INTO THE MID-MISSISSIPPI
RIVER VALLEY AND A DEEP UPPER LOW OVER NORTHERN WI. UNDERNEATH THE
UPPER LOW WAS A 978 MB SURFACE LOW NEAR RHINELANDER. A VERY TIGHT
PRESSURE GRADIENT SOUTHWEST OF THE LOW WAS SUPPORTING SURFACE WINDS
OF 25 TO 35 MPH WITH GUSTS UP TO 55 MPH. THE COLD CONVEYOR BELT
WRAPPING AROUND THE NEARLY VERTICALLY STACKED LOW WAS STILL BRINGING
SNOW TO THE FORECAST AREA...HEAVIEST OVER NORTH CENTRAL WI. EARLIER
LAST EVENING THE STRONG WINDS WERE NOT REDUCING VISIBILITIES THAT
MUCH IN SOUTHEAST MN/NORTHEAST IA PER ASOS/AWOS OBSERVATIONS...DUE
TO THE WET NATURE OF THE SNOW. HOWEVER...CALLS TO COUNTY SHERIFFS
IN THE SAME AREA WERE REPORTING WHITEOUTS WITH SOME ROADS
CLOSED...SUGGESTING ASOS/AWOS OBSERVATIONS WERE NOT FULLY
REPRESENTATIVE. IN ADDITION...POWER OUTAGES WERE A MAJOR ISSUE
WITH THE WEIGHT OF THE WET SNOW ON TREES/POWER LINES AND WINDS.
NOW THE WINDS HAVE ADVECTED COLDER AIR INTO THE FORECAST AREA AS
NOTED BY TEMPERATURES IN THE TEENS TO LOW 20S. THE COLDER AIR HAS
ALLOWED THE SNOW TO BECOME DRIER...MORE ABLE TO BLOW.
THE NEARLY VERTICALLY STACKED LOW WILL CONTINUE LIFTING
NORTHEASTWARD OVER THE NEXT 24 HOURS...REACHING NORTHERN ONTARIO
THIS EVENING. AS THE LOW PULLS AWAY...THE WINDS WILL GRADUALLY
RELAX...DROPPING FROM 20 TO 35 MPH WITH HIGHER GUSTS DURING THE
MORNING TO 10 TO 25 MPH BY 00Z. FURTHER DIMINISHING OF THE WINDS ARE
EXPECTED TONIGHT. IN TERMS OF THE COLD CONVEYOR BELT OF SNOW...GOOD
AGREEMENT EXISTS THAT THE SNOW SHOULD EXIT MOST LOCATIONS WEST OF
THE MISSISSIPPI RIVER BY 12Z...LOCATIONS SOUTHWEST OF I-94 BY
18Z...AND THE CHIMNEY AREA BY 00Z. MUCH OF THE SNOW SHOULD BE
LIGHT WITH THE SYSTEM OCCLUDED AND MOVING AWAY. JUXTAPOSITION OF
THE WINDS AND SNOW SUGGESTS CONTINUATION OF HAZARDS OVER THE
NORTHWEST HALF OF THE FORECAST AREA. CONTEMPLATED RIGHT NOW
CANCELING SOME OF THE WINTER WEATHER ADVISORY...BUT HAVE KEPT IT
GOING FOR NOW DUE TO LIGHT SNOW GOING THROUGH AND STRONG WINDS
ALLOWING THAT TO BLOW AROUND...WINDS AT ADVISORY LEVEL...AND COLD
AIR ALLOWING RECENT WATER TO FREEZE.
WE SHOULD ALSO SEE SOME CLEARING TODAY SOUTHWEST TO NORTHEAST AS
DRIER/SUBSIDENT AIR OVER THE PLAINS ADVECTS IN BEHIND THE SYSTEM.
THIS CLEARING IS WELL EVIDENT OVER WESTERN IOWA AND FAR SOUTHWEST MN
CURRENTLY. THE DRIER AIR HOLDS INTO TONIGHT...SO ALTHOUGH SOME
SHORTWAVES ROTATING AROUND THE UPPER LOW ARE PROGGED TO COME ACROSS
THE FORECAST AREA...NO PRECIPITATION OR EVEN CLOUD IMPACTS ARE
EXPECTED FROM THEM.
925MB TEMPERATURES OF -8 TO -12C TODAY WILL RESULT IN MUCH COOLER
HIGHS TODAY COMPARED TO YESTERDAY...AS MUCH AS 15 TO 20 DEGREES
COLDER. 925MB TEMPS COOL EVEN MORE TONIGHT...TO -10 TO -16C BY 12Z
SATURDAY...COLDEST NORTH. HAVING MOSTLY CLEAR SKIES...COOLING TEMPS
AND FRESH SNOW IS CONCERNING FOR TEMPERATURES TO TANK...BUT MIXING
OF THE WINDS SHOULD HELP KEEP MOST LOCATIONS ABOVE 0F. THE LONE
EXCEPTION TO GO BELOW ZERO COULD BE UP IN TAYLOR COUNTY WHERE THE
COLDEST AIR IS FLOWING IN. COMBINATION OF THE WINDS AND FALLING
TEMPS BRINGS WIND CHILLS CLOSE BUT NOT TO -20F...WHEN WE WOULD ISSUE
WIND CHILL ADVISORIES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 214 AM CST FRI FEB 21 2014
MUCH OF THE LONG TERM PERIOD IS DOMINATED BY A STUCK UPPER LEVEL
PATTERN...RESULTING FROM AN OMEGA BLOCK THAT DEVELOPS AND
STRENGTHENS FROM ALONG THE U.S. WEST COAST INTO FAR WESTERN CANADA.
THE STRENGTHENING OMEGA BLOCK CORRELATES WELL WITH A STRATOSPHERIC
WARMING EVENT TAKING PLACE OVER THE ALEUTIANS THE NEXT FEW DAYS.
THIS OMEGA BLOCK WILL ALLOW A SERIES OF SHORTWAVE TROUGHS DROPPING
OUT OF THE ARCTIC TO COME THROUGH THE FORECAST AREA. IN THE WAKE OF
EACH TROUGH...A SURGE OF COLDER AIR WITH ARCTIC HIGH PRESSURE WILL
FOLLOW. GIVEN THE ARCTIC NATURE OF THE SHORTWAVES...MOISTURE AND
PRECIPITATION IS GOING TO BE HARD TO COME BY. THE ONLY REAL CHANCE
IT LOOKS LIKE FOR SNOW WILL COME MONDAY INTO MONDAY NIGHT WITH A
SHORTWAVE TROUGH DROPPING THROUGH THEN. STILL...AT THIS POINT...IT
DOES NOT APPEAR TO BE A BIG SNOW PRODUCER. HIGHEST CHANCES ARE
SITUATED OVER THE SOUTHWEST HALF OF THE FORECAST AREA.
NOW THE MAIN IMPACT ISSUE...THE COLD...WHICH HAS BEEN CONSISTENTLY
FORECASTED FROM THE ECMWF/GFS AND CFS. HAVING ARCTIC COLD FLOW INTO
THE FORECAST AREA ALSO CORRELATES WELL WITH THE AFOREMENTIONED
STRATOSPHERIC WARMING OVER THE ALEUTIANS.
THE WEEKEND...925MB TEMPS ARE NOT FORECAST TO CHANGE MUCH THROUGH
THE WEEKEND FROM THE -10 TO -16C PROGGED AT 12Z SATURDAY. THIS
SHOULD RESULT IN HIGHS SIMILAR FOR BOTH DAYS...RANGING FROM THE LOW
TEENS TO LOW 20S. TEMPERATURES SATURDAY NIGHT COULD FALL QUITE A BIT
WITH A WEAKER PRESSURE GRADIENT. TYPICAL COLD SPOTS WILL LIKELY
DECOUPLE...ALLOWING THEM TO APPROACH 10 BELOW. WIND CHILLS MAY FLIRT
WITH ADVISORY CRITERIA AS WELL SUNDAY MORNING.
NEXT WEEK...BEHIND THE MONDAY SHORTWAVE TROUGH...925MB TEMPS FALL TO
-18 TO -22C BY 12Z TUESDAY PER 21.00Z ECMWF/GFS. A COLDER SURGE
COMES IN TUESDAY NIGHT BEHIND ANOTHER SHORTWAVE TROUGH...WITH THOSE
925MB TEMPS DOWN TO -22 TO -26C AT 12Z WEDNESDAY. MORE IMPORTANTLY
WITH THIS COLD SURGE IS STRONGER 925MB WINDS OF 25-35 KTS...WHICH
RESULTS IN WIND CHILL ADVISORY NEED. THE FINAL AND COLDEST OF THE
COLD COMES WEDNESDAY NIGHT INTO THURSDAY. 925MB TEMPS ARE SIMILAR TO
THE TUESDAY NIGHT SURGE...BUT 850MB TEMPS APPROACH -30C IN TAYLOR
COUNTY...SUGGESTING A DEEPER COLDER AIRMASS. AND LIKE TUESDAY
NIGHT...PLENTY OF WIND IS FORECAST...SO WIND CHILL ADVISORY HAZARDS
LOOK LIKELY. IN FACT...LOWS THEMSELVES SHOULD BE IN THE SINGLE
DIGITS TO TEENS BELOW ZERO TUESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1118 PM CST THU FEB 20 2014
THE SNOW WITH THE STORM SYSTEM CONTINUES TO LIFT SLOWLY NORTHEAST
WITH THE RADAR SHOWING THE HEAVIEST SNOW NOW NORTH OF BOTH TAF
SITES. EXPECT THIS TREND TO CONTINUE THROUGH THE NIGHT AS THE LOW
CONTINUES TO PULL OFF TO THE NORTH/NORTHEAST WITH THE SNOW ENDING
BEFORE 12Z AT BOTH SITES. THE STRONGEST WINDS ARE JUST MOVING INTO
THE AREA AND EXPECT THE GUSTS OF 35 TO 40 KNOTS TO CONTINUE FOR
MUCH OF THE NIGHT WITH SOME DECREASE EXPECTED TO OCCUR BY MID
MORNING FRIDAY WITH THE GUSTS COMING DOWN TO 30 TO 35 KNOTS. THESE
WINDS WILL PRODUCE BLOWING SNOW AT KRST WITH IFR VISIBILITIES
EXPECTED UNTIL THE WINDS SETTLE DOWN A LITTLE BIT TO ALLOW THE
VISIBILITY TO COME UP TO MVFR. THE WINDS SHOULD THEN STAY STRONG
ENOUGH TO CONTINUE TO PRODUCE SOME BLOWING SNOW THROUGH MUCH OF
THE DAY. CEILINGS PRIMARILY EXPECTED TO BE MVFR UNTIL THE CLOUDS
SCATTER OUT EARLY FRIDAY AFTERNOON. THE WINDS SHOULD SETTLE DOWN
EVEN MORE LATE FRIDAY AFTERNOON OR EARLY EVENING AS THE GRADIENT
RELAXES SOME MORE AND THE LOW LEVEL INVERSION BEGINS TO DEVELOP.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR WIZ017-029-032>034.
MN...BLIZZARD WARNING UNTIL NOON CST TODAY FOR MNZ079-086-087-094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ096.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR MNZ088.
IA...BLIZZARD WARNING UNTIL NOON CST TODAY FOR IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR IAZ011-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
535 AM MST FRI FEB 21 2014
.UPDATE...
&&
.SHORT TERM...WINDS HAVE DROPPED OFF TO BLO WARNING LEVELS EVEN AT
THE NORMAL WINDY SPOTS SO WILL CANCEL THE HI WIND WARNING EARLY.
.PREV DISCUSSION... /ISSUED 344 AM MST FRI FEB 21 2014/
SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA TODAY THRU
TONIGHT. DECENT WIND EVENT OCCURRED LATE LAST EVENING INTO THE
EARLY MORNING HOURS IN AND NEAR THE FOOTHILLS OF BOULDER AND
JEFFERSON COUNTIES AS GUSTS RANGED FROM 70-90 MPH. THE LAST FEW
HOURS WINDS HAVE DECREASED WITH GUSTS MAINLY IN THE 50-60 MPH
RANGE WITH A FEW GUSTS TO 70 MPH AT TIMES. OVERALL MTN WAVE SHOULD
BREAKDOWN BY 12Z WITH THREAT OF HIGH WINDS GRADUALLY BY 9 AM IF
NOT SOONER. HOWEVER IT STILL WILL BE VERY WINDY AT TIMES THROUGH
MIDDAY.
IN THE MTNS MOISTURE WAS INCREASING EARLY THIS MORNING AND COMBINED
WITH FAVORABLE OROGRAPHICS WAS PRODUCING SNOW IN THE MTNS WITH
AREAS OF BLOWING SNOW OVER THE HIGHER PASSES. MOISTURE IS FCST TO
DECREASE BY MIDDAY THRU THE EARLY EVENING HOURS SO SNOW COVERAGE
WILL LIKELY DECREASE BY 18Z ALTHOUGH AREAS OF BLOWING SNOW WILL
STILL BE POSSIBLE.
ACROSS NERN CO WITH RATHER STG NWLY FLOW IN THE LOWER LEVELS AS
MIXING OCCURS LATER THIS MORNING THRU THE AFTN HOURS WILL SEE
GUSTY NORTHWEST WINDS WITH SOME GUSTS IN THE 40-50 MPH RANGE AT
TIMES. AS FOR HIGHS WILL KEEP READINGS IN THE 45 TO 50 DEGREE
RANGE OVER THE PLAINS.
FOR TONIGHT MOISTURE MAY INCREASE IN THE MTNS AFTER MIDNIGHT WITH
BETTER COVERAGE OF SNOW ESPECIALLY NORTH OF I-70. WINDS WILL REMAIN
GUSTY IN THE MTNS AND FOOTHILLS HOWEVER CROSS MTN FLOW IS ONLY IN
THE 45-50 KT RANGE OVERNIGHT WITH A WEAKER MTN WAVE AS COMPARED
TO LAST NIGHT. THUS POTENTIAL FOR HIGH WINDS LOOKS ON THE LOW SIDE AT
THIS POINT HOWEVER STILL MAY SEE A FEW GUSTS TO 60-70 MPH AT TIMES
IN A FEW LOCATIONS.
LONG TERM...STRONG WESTERLY JET LEVEL FLOW IS PROGGED TO
CONTINUE OVER THE CWA SATURDAY INTO SUNDAY MORNING. FOR THE REST
TO SUNDAY AND SUNDAY NIGHT...THE FLOW ALOFT DECREASES A BIT AND IS
WEST-NORTHWESTERLY. THERE IS QG ASCENT PROGGED FOR THE CWA
SATURDAY INTO THE EARLY EVENING...THEN DOWNWARD MOTION IS PROGGED
WELL INTO SUNDAY. THERE IS WEAK UPWARD TO NEUTRAL SYNOPTIC SCALE
ENERGY FOR SUNDAY NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS
POINT TO NORMAL DIURNAL PATTERNS FOR WINDS SATURDAY. MODELS DO
NOT BRING THE COLD FRONT INTO THE CWA UNTIL LATE AFTERNOON/EARLY
EVENING. UPSLOPE IS PROGGED ALL OF SATURDAY NIGHT...WITH
SOUTHEASTERLIES ON SUNDAY. TROUGHING IS PROGGED TO DEVELOP EAST OF
THE MOUNTAINS SUNDAY NIGHT...AND ENHANCED DRAINAGE WIND PATTERNS
CAN BE EXPECTED FOR THE PLAINS AND FOOTHILLS. FOR MOISTURE...
THERE IS SOME OVER THE MOUNTAINS ON SATURDAY...AND LITTLE OVER THE
PLAINS. IT IS A BIT DEEPER OVER THE MOUNTAINS SATURDAY NIGHT...
WITH A BIT AT THE LOWER LEVELS FOR THE PLAINS. THERE IS SOME
MOISTURE HANGING AROUND OVER THE MOUNTAINS SUNDAY AND SUNDAY
NIGHT...WITH A BIT OVER THE PLAINS IN THE MORNING ONLY. OVERALL
..MOISTURE IS LESS ON THESE 00Z MODEL RUNS COMPARED TO
YESTERDAY`S. THE QPF FIELDS HAVE SMALL AMOUNTS OF MEASURABLE
SNOWFALL OVER THE MOUNTAINS SATURDAY THROUGH ABOUT MID DAY SUNDAY.
THERE IS A TAD OVER THE PLAINS...MOSTLY THE NORTHERN HALF...
SATURDAY AFTERNOON LATE INTO SUNDAY MORNING. FOR POPS WILL GO WITH
40-70%S IN THE MOUNTAINS SATURDAY AND SATURDAY NIGHT. WILL GO WITH
"CHANCE"S OVER THE NORTHERN HALF OF THE PLAINS SATURDAY NIGHT.
WINDS SHOULD BE BE PARTICULARLY STRONG. THERE WILL BE SOME
DECREASING POPS OVER THE MOUNTAINS AND NORTHEAST CORNER ON SUNDAY.
SUNDAY NIGHT SHOULD BE DRY. FOR TEMPERATURES...SATURDAY`S HIGHS
SHOULD ONLY BE A TAD COLDER THAN TODAY`S...ESPECIALLY SINCE THE
COLD FRONT IS PROGGED IN LATE DAY. SUNDAY`S HIGHS ARE 1-3 C COLDER
THAN SATURDAY`S. FOR THE LATER DAYS...MONDAY THROUGH THURSDAY...
WEAKER WEST-NORTHWESTERLY FLOW IS PROGGED MONDAY INTO TUESDAY. A
WEAK UPPER TROUGH SLIDES IN FROM THE NORTHWEST LATER TUESDAY AND
TUESDAY NIGHT WITH AN ASSOCIATED COLD FRONT. TUESDAY LOOKS TO HAVE
BETTER POPS FOR ALL THE CWA THAN PREVIOUS MODELS INDICATED. THE
WEST-NORTHWESTERLY FLOW ALOFT CONTINUES ON WEDNESDAY AND
THURSDAY. THERE IS AN UPPER RIDGE AXIS JUST WEST OF THE CWA ON
THURSDAY.
&&
.AVIATION...WNW WINDS WERE ALREADY OCCURRING AT DIA WITH GUSTS
TO 25 MPH AT TIMES EARLY THIS MORNING. BOTH THE HRRR AND RAP SHOW
GUSTY WNW WINDS THRU 00Z WITH SOME GUSTS TO 40 MPH AT TIMES.
AFTER 00Z WINDS MAY BECOME MORE WLY WITH SPEEDS IN THE 10-20 MPH
RANGE WHICH WILL GRADUALLY BECOME MORE SSW AFTER 03Z. OTHERWISE
EXPECT VFR CONDITIONS TODAY THRU TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
344 AM MST FRI FEB 21 2014
.SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA TODAY THRU
TONIGHT. DECENT WIND EVENT OCCURRED LATE LAST EVENING INTO THE
EARLY MORNING HOURS IN AND NEAR THE FOOTHILLS OF BOULDER AND
JEFFERSON COUNTIES AS GUSTS RANGED FROM 70-90 MPH. THE LAST FEW
HOURS WINDS HAVE DECREASED WITH GUSTS MAINLY IN THE 50-60 MPH
RANGE WITH A FEW GUSTS TO 70 MPH AT TIMES. OVERALL MTN WAVE SHOULD
BREAKDOWN BY 12Z WITH THREAT OF HIGH WINDS GRADUALLY BY 9 AM IF
NOT SOONER. HOWEVER IT STILL WILL BE VERY WINDY AT TIMES THROUGH
MIDDAY.
IN THE MTNS MOISTURE WAS INCREASING EARLY THIS MORNING AND COMBINED
WITH FAVORABLE OROGRAPHICS WAS PRODUCING SNOW IN THE MTNS WITH
AREAS OF BLOWING SNOW OVER THE HIGHER PASSES. MOISTURE IS FCST TO
DECREASE BY MIDDAY THRU THE EARLY EVENING HOURS SO SNOW COVERAGE
WILL LIKELY DECREASE BY 18Z ALTHOUGH AREAS OF BLOWING SNOW WILL
STILL BE POSSIBLE.
ACROSS NERN CO WITH RATHER STG NWLY FLOW IN THE LOWER LEVELS AS
MIXING OCCURS LATER THIS MORNING THRU THE AFTN HOURS WILL SEE
GUSTY NORTHWEST WINDS WITH SOME GUSTS IN THE 40-50 MPH RANGE AT
TIMES. AS FOR HIGHS WILL KEEP READINGS IN THE 45 TO 50 DEGREE
RANGE OVER THE PLAINS.
FOR TONIGHT MOISTURE MAY INCREASE IN THE MTNS AFTER MIDNIGHT WITH
BETTER COVERAGE OF SNOW ESPECIALLY NORTH OF I-70. WINDS WILL REMAIN
GUSTY IN THE MTNS AND FOOTHILLS HOWEVER CROSS MTN FLOW IS ONLY IN
THE 45-50 KT RANGE OVERNIGHT WITH A WEAKER MTN WAVE AS COMPARED
TO LAST NIGHT. THUS POTENTIAL FOR HIGH WINDS LOOKS ON THE LOW SIDE AT
THIS POINT HOWEVER STILL MAY SEE A FEW GUSTS TO 60-70 MPH AT TIMES
IN A FEW LOCATIONS.
.LONG TERM...STRONG WESTERLY JET LEVEL FLOW IS PROGGED TO
CONTINUE OVER THE CWA SATURDAY INTO SUNDAY MORNING. FOR THE REST
TO SUNDAY AND SUNDAY NIGHT...THE FLOW ALOFT DECREASES A BIT AND IS
WEST-NORTHWESTERLY. THERE IS QG ASCENT PROGGED FOR THE CWA
SATURDAY INTO THE EARLY EVENING...THEN DOWNWARD MOTION IS PROGGED
WELL INTO SUNDAY. THERE IS WEAK UPWARD TO NEUTRAL SYNOPTIC SCALE
ENERGY FOR SUNDAY NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS
POINT TO NORMAL DIURNAL PATTERNS FOR WINDS SATURDAY. MODELS DO
NOT BRING THE COLD FRONT INTO THE CWA UNTIL LATE AFTERNOON/EARLY
EVENING. UPSLOPE IS PROGGED ALL OF SATURDAY NIGHT...WITH
SOUTHEASTERLIES ON SUNDAY. TROUGHING IS PROGGED TO DEVELOP EAST OF
THE MOUNTAINS SUNDAY NIGHT...AND ENHANCED DRAINAGE WIND PATTERNS
CAN BE EXPECTED FOR THE PLAINS AND FOOTHILLS. FOR MOISTURE...
THERE IS SOME OVER THE MOUNTAINS ON SATURDAY...AND LITTLE OVER THE
PLAINS. IT IS A BIT DEEPER OVER THE MOUNTAINS SATURDAY NIGHT...
WITH A BIT AT THE LOWER LEVELS FOR THE PLAINS. THERE IS SOME
MOISTURE HANGING AROUND OVER THE MOUNTAINS SUNDAY AND SUNDAY
NIGHT...WITH A BIT OVER THE PLAINS IN THE MORNING ONLY. OVERALL
...MOISTURE IS LESS ON THESE 00Z MODEL RUNS COMPARED TO
YESTERDAY`S. THE QPF FIELDS HAVE SMALL AMOUNTS OF MEASURABLE
SNOWFALL OVER THE MOUNTAINS SATURDAY THROUGH ABOUT MID DAY SUNDAY.
THERE IS A TAD OVER THE PLAINS...MOSTLY THE NORTHERN HALF...
SATURDAY AFTERNOON LATE INTO SUNDAY MORNING. FOR POPS WILL GO WITH
40-70%S IN THE MOUNTAINS SATURDAY AND SATURDAY NIGHT. WILL GO WITH
"CHANCE"S OVER THE NORTHERN HALF OF THE PLAINS SATURDAY NIGHT.
WINDS SHOULD BE BE PARTICULARLY STRONG. THERE WILL BE SOME
DECREASING POPS OVER THE MOUNTAINS AND NORTHEAST CORNER ON SUNDAY.
SUNDAY NIGHT SHOULD BE DRY. FOR TEMPERATURES...SATURDAY`S HIGHS
SHOULD ONLY BE A TAD COLDER THAN TODAY`S...ESPECIALLY SINCE THE
COLD FRONT IS PROGGED IN LATE DAY. SUNDAY`S HIGHS ARE 1-3 C COLDER
THAN SATURDAY`S. FOR THE LATER DAYS...MONDAY THROUGH THURSDAY...
WEAKER WEST-NORTHWESTERLY FLOW IS PROGGED MONDAY INTO TUESDAY. A
WEAK UPPER TROUGH SLIDES IN FROM THE NORTHWEST LATER TUESDAY AND
TUESDAY NIGHT WITH AN ASSOCIATED COLD FRONT. TUESDAY LOOKS TO HAVE
BETTER POPS FOR ALL THE CWA THAN PREVIOUS MODELS INDICATED. THE
WEST-NORTHWESTERLY FLOW ALOFT CONTINUES ON WEDNESDAY AND
THURSDAY. THERE IS AN UPPER RIDGE AXIS JUST WEST OF THE CWA ON
THURSDAY.
&&
.AVIATION...WNW WINDS WERE ALREADY OCCURRING AT DIA WITH GUSTS
TO 25 MPH AT TIMES EARLY THIS MORNING. BOTH THE HRRR AND RAP SHOW
GUSTY WNW WINDS THRU 00Z WITH SOME GUSTS TO 40 MPH AT TIMES.
AFTER 00Z WINDS MAY BECOME MORE WLY WITH SPEEDS IN THE 10-20 MPH
RANGE WHICH WILL GRADUALLY BECOME MORE SSW AFTER 03Z. OTHERWISE
EXPECT VFR CONDITIONS TODAY THRU TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 9 AM MST THIS MORNING FOR COZ033>036-038-
039.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS ALBANY NY
1032 AM EST FRI FEB 21 2014
.SYNOPSIS...
AHEAD OF A COLD FRONT...MILDER AIR WILL MOVE INTO THE REGION FOR
TODAY...ALONG WITH RAIN SHOWERS...GUSTY WINDS OVER THE HIGH
TERRAIN...AND A SLIGHT CHANCE FOR A THUNDERSTORM. AFTER THE FRONT
PASSES THROUGH THE REGION LATE TODAY...THE THREAT FOR RAIN SHOWERS
WILL END. DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL INTO
THE WEEKEND...BUT MUCH COLDER AIR WILL RETURN TO THE REGION FOR MUCH
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1015 AM...TEMPS IN NY WERE ALL ABOVE FREEZING...WITH JUST A
FEW POCKETS OF BELOW FREEZING TEMPS IN SOUTHERN VERMONT AND
BERKSHIRE COUNTY. HOWEVER...RADAR INDICATES TO ADDITIONAL PCPN WILL
OCCUR IN SOUTHERN VERMONT AND BERKSHIRE COUNTY UNTIL THIS
AFTERNOON...AT WHICH TIME TEMPS WILL BE ABOVE FREEZING IN ALL AREAS
THERE AS WELL. AS A RESULT...HAVE CANCELLED ANY REMAINING WINTER
WEATHER ADVISORIES. HAVE ALSO MADE ADJUSTMETNS TO THE HOURLY TEMP
AND POP GRIDS TO REFLECT CURRENT CONDITIONS AND TRENDS.
.PREVIOUS DISCUSSION...
AS OF 621 AM EST...A STRONG STORM SYSTEM AND POTENT UPPER LEVEL
SHORTWAVE IS MOVING ACROSS THE UPPER GREAT LAKES. A WARM FRONT
ASSOCIATED WITH THIS STORM IS HAVING A TOUGH TIME MOVING ACROSS
OUR REGION...DUE TO PLENTY OF LOW LEVEL COLD AIR IN PLACE THANKS
TO A DEEP SNOW PACK. TEMPERATURES CONTINUE TO BE IN THE 30S ACROSS
OUR ENTIRE REGION.
STEADY PRECIPITATION HAS MOVED NORTH AND EAST OF THE REGION...AS
THE BEST ISENTROPIC LIFT/WARM AIR ADVECTION IS NOW FOCUSED ACROSS
NORTHERN NEW ENGLAND. WITH TEMPERATURES WARMING THROUGH THE 30S
AND MOST OF THE PRECIPITATION DONE...WE/VE CANCELLED THE WINTER
WEATHER ADVISORY FOR MOST OF THE AREA. WE WILL CONTINUE IT FOR A
LITTLE LONGER FOR THE EASTERN ADIRONDACKS...LAKE GEORGE AREA...AND
SRN VT...AS SOME LIGHT PRECIPITATION REMAINS THERE...AND SOME
POCKETS OF 30-32 DEGREES ARE STILL OCCURRING ACCORDING TO MESO OBS
AT THIS TIME. ONCE TEMPS WARM UP AND PRECIP ENDS...WE SHOULD BE
ABLE TO CANCEL THE ADVISORY.
AS SHOWN IN THE MODELS...THIS BREAK IN THE PRECIP LOOKS TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS. WE HAVE LOWERED POPS
TO CHC THROUGH THE MID MORNING HOURS FOR CENTRAL/SOUTHERN PARTS OF
THE AREA. HOWEVER...THE MOIST SOUTHERLY FLOW...COMBINED WITH SOME
UPSLOPE...MAY ALLOW FOR SOME SPOTTY AREAS OF LIGHT RAIN SHOWERS BY
LATER THIS MORNING...SO WE WILL RAISE POPS BACK UP TO LIKELY FOR
THE LATE MORNING HOURS. MAX TEMPS SHOULD WARM UP INTO THE LOWER TO
MID 40S FOR VALLEY AREAS...WITH UPPER 30S IN THE HIGH TERRAIN WITH
THESE HIGHS IN THE LATE MORNING TO EARLY AFTERNOON.
THE STORM/S COLD FRONT LOOKS TO MOVE FROM WEST TO EAST DURING THE
AFTERNOON HOURS. A STRONGLY FORCED LINE OF SHOWERS...AND POSSIBLY
SOME ISOLATED THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS IS
SEEN IN THE 09Z 3KM HRRR AS WELL...WITH THE TIMING ACROSS OUR
AREA BASICALLY FROM 1 PM THROUGH 5 PM. SHOWALTER VALUES LOOK TO BE
JUST BELOW ZERO...SO SOME ELEVATED INSTABILITY IS POSSIBLE FOR A
RUMBLE OR TWO OF THUNDER...BUT NO STRONG/SEVERE STORMS ARE
ANTICIPATED DUE TO MEAGER SURFACE BASED INSTABILITY. ONCE THE
FRONT GOES THROUGH...THE THREAT FOR SHOWERS WILL DIMINISH
GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION AT
SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY QPF
WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER QUICKLY.
WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH EXPECTED
COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE SNOW...PERHAPS
MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR VALLEY AREAS. JUST AN
INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR NOW...WILL JUST GO WITH CHC
POPS FOR SUN/SUN NIGHT DUE TO UNCERTAINTY REGARDING ITS EXACT
TRACK/TIMING. MAX TEMPS WILL BE IN THE 30S...AND MINS SUNDAY NIGHT
LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
MUCH OF THE RAIN HAS ENDED AT LEAST FOR NOW AT THE TAF SITES WITH
THE NEXT BATCH OF RAIN AHEAD OF THE COLD FRONT NOT EXPECTED TO
ARRIVE UNTIL EARLY AFTERNOON. THE TAF SITES UP UNTIL THIS TIME ARE
EXPECTED TO BE MVFR AT KGFL AND KALB WITH IFR/LIFR CONDITIONS
EXPECTED AT KPSF AND KPOU WHERE FOG AND LOW STRATUS WL BE PRESENT.
IFR CONDITIONS ARE EXPECTED AT ALL OF THE TAF SITES STARTING ARND
18Z AS THE NEXT BATCH OF RAIN MOVES IN. A COLD FRONT WL SWEEP
THROUGH THE RGN LATE THIS AFTERNOON WITH SKIES BECOMING SKC THIS
EVENING IN THE WAKE OF THE COLD FRONT.
WINDS WILL BE LIGHT AND VARIABLE UNTIL EARLY AFTERNOON AND THEN
NE-SE ARND 5 KTS AHD OF THE FRONT AND WEST TO SOUTHWEST AT 6 TO 10
KTS IN THE WAKE OF THE COLD FRONT.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3+ FEET.
TEMPERATURES ARE CURRENTLY IN THE LOWER TO MIDDLE 30S...WITH STEADY
RAIN AND FREEZING RAIN OCCURRING ACROSS THE NORTHERN HALF OF THE
REGION AS A WARM FRONT MOVES ACROSS THE REGION. WITH A SOUTHERLY
FLOW DEVELOPING...TEMPERATURES WILL BRIEFLY BE ABOVE NORMAL
TODAY...WITH HIGHS IN THE UPPER 30S TO MID 40S...ALONG WITH SOME
ADDITIONAL RAIN SHOWERS. HOWEVER...COLDER AIR WILL QUICKLY RETURN
BEHIND THIS AFTERNOON/S COLD FRONT...WITH TEMPERATURES DROPPING BACK
BELOW FREEZING ACROSS THE ENTIRE REGION BY TONIGHT.
STORM TOTAL QPF WILL BE A HALF INCH TO NEARLY ONE AND A HALF
INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DAYTIME TEMPERATURES OVER THE WEEKEND WILL CONTINUE TO BE ABOVE
FREEZING...AND OVERNIGHT LOWS WILL DROP BELOW FREEZING. THIS SHOULD
ALLOW FOR A STEADY CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY
FLOODING CONCERNS. MUCH COLDER WEATHER...WITH TEMPERATURES
COMPLETELY BELOW FREEZING...WILL RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION A SLIGHT CHC FOR AN ISOLATED ICE JAM ON
SMALLER STREAMS AND CREEK IN THE HWO STATEMENT FOR TODAY INTO
TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT WIDESPREAD
FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ033-041>043-082>084.
MA...NONE.
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...GJM/FRUGIS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
729 AM EST FRI FEB 21 2014
.SYNOPSIS...
AN APPROACHING WARM FRONT BRINGS PERIODS OF RAIN AND DRIZZLE TO
THE AREA THIS MORNING...WITH POCKETS OF FREEZING RAIN TO THE
HIGHER TERRAIN. WARMER AIR THEN INVADES CONNECTICUT...RHODE ISLAND
AND EASTERN MASSACHUSETTS THIS AFTERNOON ALONG WITH GUSTY
SHOWERS...AN ISOLATED THUNDERSTORM AND LOCALLY HEAVY RAINFALL.
MILD WEATHER THIS WEEKEND FOLLOWED BY MUCH COLDER WEATHER NEXT
WEEK. A PERIOD OF SNOW IS POSSIBLE SUNDAY NIGHT AND AGAIN THE
MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
LITTLE BREAK IN THE ACTION WITH MAJORITY OF THE WARM ADVECTION
PRECIP ACROSS NORTHERN NEW ENGLAND...WITH JUST ONE BAND LEFT
ACROSS EASTERN MA. OTHERWISE PRECIP FOR THE REMAINDER OF THIS
MORNING INTO EARLY THIS AFTERNOON SHOULD BE MAINLY LIGHT/NUISANCE
TYPE DRIZZLE AND/OR SPOTTY LIGHT RAIN. EXPECT COOL CONDITIONS MUCH
OF THE DAY WITH WARM SECTOR POSSIBLY PUNCHING INTO RI AND
SOUTHEAST MA LATER THIS AFTERNOON.
ONLY CHANGE TO THE FORECAST WAS TO HIT A BIT HARDER THE POTENTIAL
FOR ELEVATED CONVECTION ALONG AND AHEAD OF APPROACHING COLD FRONT.
SPC MESOANALYSIS INDICATES STEEP MID LEVEL LAPSE RATES ADVECTING
NORTHWARD FROM THE MID ATLC STATES. THIS COUPLED WITH FRONTAL
CONVERGENCE THIS AFTERNOON AND QG FORCING FROM STRONG UPPER LEVEL
JET SHOULD BE SUFFICIENT TO INITIATE ELEVATED CONVECTION. PAST FEW
RUNS OF HRRR SUPPORT THIS THINKING WITH THIS MODEL SIMULATING AN
ORGANIZED FINE LINE OF LOW TOP CONVECTION MOVING ACROSS THE AREA 3
PM TO 7 PM FROM WEST TO EAST. MAIN CONCERN IS IF CONVECTION FIRES
SUBTROPICAL MOISTURE PLUME WITH PWATS +3 STD FROM CLIMO YIELDS A
RISK OF HEAVY RAINFALL. THIS COMBINED WITH ALREADY SNOW CLOGGED
STORM DRAINS MAY RESULT IN WIDESPREAD STREET AND HIGHWAY FLOODING
DURING THE LATE DAY COMMUTE. THUS HAVE ISSUED A SPECIAL WEATHER
STATEMENT TO HEIGHTEN PUBLIC AWARENESS. FLY IN THE OINTMENT WILL
BE IF CONVECTION UPSTREAM ACROSS THE SOUTHEAST STATES ROBS
MOISTURE AND INSTABILITY FROM BEING TRANSPORTED NORTHWARD. DAY
SHIFT WILL HAVE TO MONITOR THIS. EARLIER DISCUSSION BELOW.
================================================================
4 AM UPDATE...THE FIRST OF TWO ROUNDS OF PRECIP IS OVER SOUTHERN NEW
ENGLAND CURRENTLY...WITH THE HEAVIEST PRECIP IN SOUTHERN NEW
HAMPSHIRE. THESE NEXT FEW HOURS WILL BE THE MOST COMPLICATED PART OF
THE FORECAST WITH THE SURFACE TEMPERATURES PLAYING SUCH AN IMPORTANT
ROLE. TEMPERATURES ACROSS THE AREA ARE HOVERING RIGHT AROUND
FREEZING WITH A FEW LOCATIONS BELOW FREEZING AND THE MAJORITY JUST
ABOVE. DEWPOINTS ARE ALSO JUST BELOW FREEZING SO ANY HEAVY
PRECIPITATION THAT MOVES OVER THOSE AREAS WILL LIKELY BE ENOUGH TO
COOL THE TEMPERATURES TO FREEZING OR JUST BELOW. ALOFT THE
ATMOSPHERE IS WARM ENOUGH NOW FOR PRECIPITATION TO BE FALLING AS
RAIN ACROSS SOUTHERN NEW ENGLAND. THE ONLY QUESTION IS WHETHER THE
TEMPERATURES AT THE SURFACE WILL BE ABOVE OR BELOW FREEZING. IN THE
AREAS WHERE THE TEMPERATURES ARE BELOW FREEZING OR FALL BELOW
FREEZING...ICING WILL BE A CONCERN. NOT EXPECTING MUCH IN THE WAY
OF ICING...LESS THAN A TENTH OF AN INCH...BUT EVEN THE LIGHTEST
AMOUNTS OF ICING CAN WREAK HAVOC ON TRAVEL. SO WILL LEAVE THE
WINTER WEATHER ADVISORY IN PLACE FOR PORTIONS OF MASSACHUSETTS AND
SOUTHERN NEW HAMPSHIRE.
BY MID-MORNING...TEMPERATURES SHOULD RISE ABOVE FREEZING
EVERYWHERE...ALLOWING ANY REMAINING PRECIPITATION TO FALL AS RAIN.
AT THIS POINT...THE CONCERN WILL TURN TO HEAVY RAIN AND THUNDER
POTENTIAL FOR THE AFTERNOON. A COLD FRONT APPROACHING THE AREA...A
STRENGTHENING LOW LEVEL JET...AND STEEPENING MID LEVEL LAPSE RATES
SHOULD PROVIDE ENOUGH LIFT AND INSTABILITY FOR A CONVECTIVE LINE OF
SHOWERS JUST AHEAD OF THE COLD FRONT. IN ADDITION...PRECIPITABLE
WATER VALUES ARE 3 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR. SO ANY SHOWERS ARE LIKELY TO PRODUCE BRIEF HEAVY DOWNPOURS
AND WITH SNOW CLOGGED DRAINS...EXPECT SOME PONDING OF WATER ON ROADS
THIS AFTERNOON. DEPENDING ON THE TIMING OF THE FRONT AND THUS THE
SHOWERS AHEAD OF THE FRONT...THERE IS A POSSIBILITY OF SOME THUNDER
WITH THE LINE. HAVE KEPT A SLIGHT CHANCE OF THUNDER IN THE GRIDS FOR
THIS AFTERNOON. EXPECT THE FRONT TO MOVE THROUGH IN THE LATE
AFTERNOON INTO EARLY EVENING. IF IT COMES THROUGH DURING
DAYLIGHT...THERE WILL BE THAT INSTABILITY POTENTIAL...IF IT COMES
THROUGH LATER AFTER SOME OF THE HEATING FROM THE DAY IS
LOST...THUNDER IS LESS LIKELY.
DESPITE A RATHER HEFTY LOW LEVEL JET THE WARM AIR ALOFT WILL PREVENT
MOST OF THAT ENERGY FROM MIXING TO THE SURFACE. THE EXCEPTION TO
THIS WOULD BE IN ANY OF THOSE CONVECTIVE SHOWERS THAT OCCUR. HEAVY
RAIN IN THOSE SHOWERS COULD DRAG SOME OF THOSE STRONGER WINDS DOWN
TO THE SURFACE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
TONIGHT...AS THE COLD FRONT PUSHES OFFSHORE IT WILL TAKE THE PRECIP
WITH IT AND WE WILL BEGIN TO DRY OUT FOR A BIT. EXPECT SKIES TO
CLEAR FAIRLY QUICKLY BEHIND THE FRONT WITH MOSTLY CLEAR SKIES FOR
MUCH OF THE NIGHT. THE LOW LEVEL JET WILL KEEP WINDS FROM
DECOUPLING OVERNIGHT SO WILL NOT HAVE OPTIMAL RADIATIONAL COOLING
CONDITIONS. SO TEMPERATURES WILL REMAIN IN THE 20S TO MID 30S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
* MILD THIS WEEKEND
* ARCTIC AIR RETURNS NEXT WEEK
* HIGH AMPLITUDE PATTERN OFFERS A CHANCE OF SNOW SUN NIGHT & AGAIN
MIDDLE OF NEXT WEEK
THIS WEEKEND...
SATURDAY...DRY POST FRONTAL AIRMASS OVERSPREADS THE REGION. HOWEVER
AIRMASS IS RELATIVELY MILD WITH 850 TEMPS AROUND -2C AND 925 MB
AROUND +4C. BUFKIT SOUNDINGS SUGGEST MIXING TO AROUND 925 MB WILL
PROMOTE MAX TEMPS 45-50. HOWEVER A GUSTY SW WIND OF 20-30 MPH WILL
PROVIDE A BIT OF A WIND CHILL. NEVERTHELESS PLEASANT BY LATE FEB
STANDARDS...ALONG WITH DRY WEATHER PREVAILING.
SUNDAY...THE 00Z NAM WAS A STRONG OUTLIER WITH ITS MID LEVEL
SHORTWAVE TROUGH. THUS FOLLOWED A BLEND OF THE 00Z ECMWF/GFS AND
GEFS SOLUTIONS WHICH SUGGEST A PERIOD OF SNOW POSSIBLE LATE SUN/SUN
NIGHT INTO EARLY MON AS A FRONTAL WAVE TRACKS SOUTH OF NEW ENGLAND.
ECMWF OFFERS ONLY UP TO A TENTH OF AN INCH OF QPF WHILE THE GFS
GENERATES SEVERAL TENTHS. GEFS SIDES WITH THE OPERATIONAL GFS. UPPER
AIR PATTERN FAVORS MINOR SNOW ACCUMULATIONS GIVEN THE LACK OF SHORT
WAVE AMPLITUDE AND PROGRESSIVE NATURE. NEVERTHELESS A FEW INCHES OF
SNOW ARE POSSIBLE LATE SUN INTO EARLY MON. OTHERWISE SUNDAY WILL
START OUT DRY AND RELATIVELY MILD...BUT COOLING LATER IN THE DAY AS
FRONTAL BOUNDARY SLIPS SOUTHWARD WITH COLD AIR ADVECTION COMMENCING.
NEXT WEEK...
TEMPERATURES...LOOKS LIKE A COLD STRETCH OF WEATHER WITH THE POLAR
FRONT SLIDING SOUTH OF NEW ENGLAND ALL OF NEXT WEEK AS ALL MODEL
GUIDANCE /INCLUDING GFS-ECMWF-ECENS-GEFS/ PROJECTING 850 TEMPS OF
AROUND -15C /-1 STD FROM CLIMO/ ACROSS THE AREA MON THROUGH WED.
COLDER CONDITIONS ARE POSSIBLE LATE NEXT WEEK AS ENSEMBLES AND
DETERMINISTIC GUIDANCE HINT AT ANOTHER ARCTIC SURGE ADVECTING INTO
THE NORTHEAST WITH 850 TEMPS LOWERING TO -20C TO -25C
/-2 STD FROM CLIMO/!
PRECIPITATION...DIFFICULT AT THIS RANGE TO TIME WAVES ALONG LEADING
AND SECONDARY FRONTAL SURGES NEXT WEEK. HOWEVER ALL MODEL GUIDANCE
/AT VARYING DEGREES/ FOCUSES PRECIP CHANCES AROUND MID WEEK
WITH CYCLOGENESIS OFF THE MID ATLC COAST. THEN QUESTION BECOMES HOW
CLOSE DOES SYSTEM TRACK TO THE COAST. JET ENERGY ASSOCIATED WITH
THIS SYSTEM IS CURRENTLY OVER THE ARCTIC...A VERY DATA SPARSE AREA.
THUS MODELS WILL NOT CAPTURE THE TRUE AMPLITUDE OF THIS FEATURE
UNTIL MON OR TUE WHEN IT TRACKS INTO A MORE DATA RICH AREA OVER
SOUTHERN CANADA/NORTHERN ROCKIES. THE UPPER AIR PATTERN DOES FAVOR
SOME DEGREE OF EAST COAST STORMINESS WITH A SPLIT FLOW REGIME ACROSS
THE WEST COAST WHICH INCLUDES AN ANOMALOUS WESTERN US/CANADA RIDGE
EXTENDING INTO AK. OTHERWISE...MUCH OF NEXT WEEK LOOKS COLD AND DRY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
7 AM UPDATE...
NOT MUCH CHANGE FROM 06Z TAFS. MAIN CONCERN IS HEAVY SHOWERS WITH
EMBEDDED TSTMS 3 PM TO 7 PM FROM WEST TO EAST. EARLIER DISCUSSION
BELOW.
=================================================================
THROUGH 12Z...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN
TIMING. SEEING A MIX OF CONDITIONS...MAINLY MVFR/VFR...WITH A FEW
PATCHES OF IFR CONDITIONS. GENERALLY GOING TO SEE CONDITIONS
DECLINE TOWARDS MORNING WITH DENSE FOG DEVELOPING AS WARM AIR
MOVES OVER THE COLD SNOWPACK. IN ADDITION...-SN/FZRA IS POSSIBLE
ACROSS S NH AND PARTS OF N MA.
TODAY...MVFR/IFR CONDITIONS CONTINUE THROUGH THE DAY WITH FOG
SPREADING FARTHER NORTH INTO THE REGION. WINTRY PRECIP COMES TO AN
END SHORTLY AFTER 12Z AS TEMPERATURES WARM. HEAVY RAIN AND EVEN
SOME THUNDER IS POSSIBLE THIS AFTERNOON AHEAD OF A COLD FRONT.
LLWS IS ALSO LIKELY PARTICULARLY ACROSS RI AND SE MA AS LOW LEVEL
JET STRENGTHENS OVER THE AREA.
TONIGHT...CONDITIONS IMPROVE TO VFR AFTER MIDNIGHT.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF TRENDS.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF TRENDS.
OUTLOOK...SATURDAY THROUGH TUESDAY...
VFR LIKELY MUCH OF THIS TIME FRAME. BRIEF MVFR POSSIBLE SUNDAY NIGHT
IN A PERIOD OF LIGHT SNOW. MODEST WSW WIND SAT SHIFTS TO WNW SUN/MON
AND TUE.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SMALL CRAFT ADVISORIES CONTINUE FOR ALL OF THE COASTAL WATERS EXCEPT
BOSTON HARBOR. THESE ARE LARGELY FOR SEAS BUT THERE WILL BE A
PERIOD OF TIME THIS AFTERNOON AND EVENING WHEN A COLD FRONT MOVES
OVER THE WATERS AND SOUTHERLY WINDS WILL SWITCH TO WESTERLY WINDS
AND GUSTS UP TO 25-30 KTS ARE POSSIBLE. VISIBILITIES WILL BE
REDUCED AT TIMES IN RAIN AND THERE IS A LOW PROBABILITY OF THUNDER
ACCOMPANYING SOME OF THIS RAIN LATER THIS AFTERNOON AND EVENING.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SAT/SUN...MODEST SW WIND SAT SHIFTS TO WNW SUNDAY. VSBY GOOD BUT MAY
LOWER IN SNOW SUNDAY NIGHT.
MON/TUE...MODEST WNW WIND ALONG WITH GOOD VSBY. FREEZING SPRAY
POSSIBLE AS ARCTIC AIR OVERSPREADS THE WATERS ON A GUSTY WNW WIND.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS MOST OF SOUTHERN NEW ENGLAND RANGE FROM 1 TO
2 FEET...EXCEPT FOR SOMEWHAT LOWER AMOUNTS ALONG SOUTH COASTAL RI
AND MA. TEMPERATURES ARE FORECAST TO CLIMB GENERALLY INTO THE 40S
TO LOW 50S FRIDAY AND SATURDAY...AND OVERNIGHT LOWS WILL BE CLOSE
TO OR BELOW FREEZING. AS A RESULT SOME SNOWMELT WILL OCCUR DURING
THE DAYTIME...WITH THE MOST SNOWMELT EXPECTED ACROSS SOUTHEAST MA
AND SOUTHERN RI WHERE THE SNOWPACK IS THE MOST DENSE AND THE
WARMEST.
RAINFALL...0.25 TO 0.35 INCHES OF RAINFALL ARE EXPECTED TODAY.
LOCALLY HIGHER AMOUNTS ARE POSSIBLE IF THUNDERSTORMS DEVELOP. THIS
WILL LIKELY CAUSE PONDING OF WATER IN LOCATIONS WHERE THERE ARE
SNOW CLOGGED DRAINS. THE HEAVIEST SHOWERS WILL LIKELY OCCUR
BETWEEN 4 PM AND 8 PM. THIS TIMING MAY IMPACT THE LATE DAY COMMUTE
WITH STREET AND HIGHWAY FLOODING.
THE COMBINATION RAIN AND SNOWMELT TODAY WILL GIVE SOME AREAS SMALL
STREAMS AND RIVERS A BOOST...AND THIS MAY PROMPT ICE MOVEMENT.
THERE IS A CHANCE OF ISOLATED ICE JAM DEVELOPMENT TODAY FOR SMALL
STREAMS ACROSS CENTRAL INTO WESTERN MA AND NORTHERN CT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MAZ002>005-008>012-026.
NH...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR NHZ011-
012-015.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR ANZ231>234-
251.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM EST
SATURDAY FOR ANZ236.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ250-
254>256.
&&
$$
SYNOPSIS...NOCERA/RLG
NEAR TERM...NOCERA/RLG
SHORT TERM...RLG
LONG TERM...NOCERA
AVIATION...NOCERA/RLG
MARINE...NOCERA/RLG
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS ALBANY NY
621 AM EST FRI FEB 21 2014
.SYNOPSIS...
AHEAD OF A COLD FRONT...MILDER AIR WILL MOVE INTO THE REGION FOR
TODAY...ALONG WITH RAIN SHOWERS...GUSTY WINDS OVER THE HIGH
TERRAIN...AND A SLIGHT CHANCE FOR A THUNDERSTORM. AFTER THE FRONT
PASSES THROUGH THE REGION LATE TODAY...THE THREAT FOR RAIN SHOWERS
WILL END. DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL INTO
THE WEEKEND...BUT MUCH COLDER AIR WILL RETURN TO THE REGION FOR MUCH
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 621 AM EST...A STRONG STORM SYSTEM AND POTENT UPPER LEVEL
SHORTWAVE IS MOVING ACROSS THE UPPER GREAT LAKES. A WARM FRONT
ASSOCIATED WITH THIS STORM IS HAVING A TOUGH TIME MOVING ACROSS
OUR REGION...DUE TO PLENTY OF LOW LEVEL COLD AIR IN PLACE THANKS
TO A DEEP SNOW PACK. TEMPERATURES CONTINUE TO BE IN THE 30S ACROSS
OUR ENTIRE REGION.
STEADY PRECIPITATION HAS MOVED NORTH AND EAST OF THE REGION...AS
THE BEST ISENTROPIC LIFT/WARM AIR ADVECTION IS NOW FOCUSED ACROSS
NORTHERN NEW ENGLAND. WITH TEMPERATURES WARMING THROUGH THE 30S
AND MOST OF THE PRECIPITATION DONE...WE/VE CANCELLED THE WINTER
WEATHER ADVISORY FOR MOST OF THE AREA. WE WILL CONTINUE IT FOR A
LITTLE LONGER FOR THE EASTERN ADIRONDACKS...LAKE GEORGE AREA...AND
SRN VT...AS SOME LIGHT PRECIPITATION REMAINS THERE...AND SOME
POCKETS OF 30-32 DEGREES ARE STILL OCCURRING ACCORDING TO MESO OBS
AT THIS TIME. ONCE TEMPS WARM UP AND PRECIP ENDS...WE SHOULD BE
ABLE TO CANCEL THE ADVISORY.
AS SHOWN IN THE MODELS...THIS BREAK IN THE PRECIP LOOKS TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS. WE HAVE LOWERED POPS
TO CHC THROUGH THE MID MORNING HOURS FOR CENTRAL/SOUTHERN PARTS OF
THE AREA. HOWEVER...THE MOIST SOUTHERLY FLOW...COMBINED WITH SOME
UPSLOPE...MAY ALLOW FOR SOME SPOTTY AREAS OF LIGHT RAIN SHOWERS BY
LATER THIS MORNING...SO WE WILL RAISE POPS BACK UP TO LIKELY FOR
THE LATE MORNING HOURS. MAX TEMPS SHOULD WARM UP INTO THE LOWER TO
MID 40S FOR VALLEY AREAS...WITH UPPER 30S IN THE HIGH TERRAIN WITH
THESE HIGHS IN THE LATE MORNING TO EARLY AFTERNOON.
THE STORM/S COLD FRONT LOOKS TO MOVE FROM WEST TO EAST DURING THE
AFTERNOON HOURS. A STRONGLY FORCED LINE OF SHOWERS...AND POSSIBLY
SOME ISOLATED THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS IS
SEEN IN THE 09Z 3KM HRRR AS WELL...WITH THE TIMING ACROSS OUR
AREA BASICALLY FROM 1 PM THROUGH 5 PM. SHOWALTER VALUES LOOK TO BE
JUST BELOW ZERO...SO SOME ELEVATED INSTABILITY IS POSSIBLE FOR A
RUMBLE OR TWO OF THUNDER...BUT NO STRONG/SEVERE STORMS ARE
ANTICIPATED DUE TO MEAGER SURFACE BASED INSTABILITY. ONCE THE
FRONT GOES THROUGH...THE THREAT FOR SHOWERS WILL DIMINISH
GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION
AT SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY
QPF WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER
QUICKLY. WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH
EXPECTED COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE
SNOW...PERHAPS MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR
VALLEY AREAS. JUST AN INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR
NOW...WILL JUST GO WITH CHC POPS FOR SUN/SUN NIGHT DUE TO
UNCERTAINTY REGARDING ITS EXACT TRACK/TIMING. MAX TEMPS WILL BE IN
THE 30S...AND MINS SUNDAY NIGHT LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
MUCH OF THE RAIN HAS ENDED AT LEAST FOR NOW AT THE TAF SITES WITH
THE NEXT BATCH OF RAIN AHEAD OF THE COLD FRONT NOT EXPECTED TO
ARRIVE UNTIL EARLY AFTERNOON. THE TAF SITES UP UNTIL THIS TIME ARE
EXPECTED TO BE MVFR AT KGFL AND KALB WITH IFR/LIFR CONDITIONS
EXPECTED AT KPSF AND KPOU WHERE FOG AND LOW STRATUS WL BE PRESENT.
IFR CONDITIONS ARE EXPECTED AT ALL OF THE TAF SITES STARTING ARND
18Z AS THE NEXT BATCH OF RAIN MOVES IN. A COLD FRONT WL SWEEP
THROUGH THE RGN LATE THIS AFTERNOON WITH SKIES BECOMING SKC THIS
EVENING IN THE WAKE OF THE COLD FRONT.
WINDS WILL BE LIGHT AND VARIABLE UNTIL EARLY AFTERNOON AND THEN
NE-SE ARND 5 KTS AHD OF THE FRONT AND WEST TO SOUTHWEST AT 6 TO 10
KTS IN THE WAKE OF THE COLD FRONT.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3+ FEET.
TEMPERATURES ARE CURRENTLY IN THE LOWER TO MIDDLE 30S...WITH STEADY
RAIN AND FREEZING RAIN OCCURRING ACROSS THE NORTHERN HALF OF THE
REGION AS A WARM FRONT MOVES ACROSS THE REGION. WITH A SOUTHERLY
FLOW DEVELOPING...TEMPERATURES WILL BRIEFLY BE ABOVE NORMAL
TODAY...WITH HIGHS IN THE UPPER 30S TO MID 40S...ALONG WITH SOME
ADDITIONAL RAIN SHOWERS. HOWEVER...COLDER AIR WILL QUICKLY RETURN
BEHIND THIS AFTERNOON/S COLD FRONT...WITH TEMPERATURES DROPPING BACK
BELOW FREEZING ACROSS THE ENTIRE REGION BY TONIGHT.
STORM TOTAL QPF WILL BE A HALF INCH TO NEARLY ONE AND A HALF
INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DAYTIME TEMPERATURES OVER THE WEEKEND WILL CONTINUE TO BE ABOVE
FREEZING...AND OVERNIGHT LOWS WILL DROP BELOW FREEZING. THIS SHOULD
ALLOW FOR A STEADY CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY
FLOODING CONCERNS. MUCH COLDER WEATHER...WITH TEMPERATURES
COMPLETELY BELOW FREEZING...WILL RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION A SLIGHT CHC FOR AN ISOLATED ICE JAM ON
SMALLER STREAMS AND CREEK IN THE HWO STATEMENT FOR TODAY INTO
TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT WIDESPREAD
FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ033-041>043-082>084.
MA...NONE.
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1026 AM EST FRI FEB 21 2014
UPDATE...
A LINE OF SHOWERS AND TSTMS FROM SWAINSBORO TO LUMBER CITY
CONTINUES MOVING EAST THROUGH THE REMAINDER OF THE FFC FORECAST
AREA. MOST OF THE FFC GA COUNTIES HAVE BEEN REMOVED FROM THE
SVR TSTM WATCH 22. THE REMAINING THREE COUNTIES WILL BE REMOVED
BY 1100 PM EST. THE COLD FRONT EXTENDING FROM WARRENTON TO CORDELE
WILL EXIT THE FORECAST AREA BY EARLY AFTERNOON. RAPID CLEARING
WILL CONTINUE ACROSS NORTH AND CENTRAL GEORGIA THROUGH THE DAY.
16
PREV DISCUSSION... /ISSUED 650 AM EST FRI FEB 21 2014/
PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
AVIATION...
12Z UPDATE...
AREA OF SHOWERS AND THUNDERSTORMS HAS ALMOST PUSHED EAST OF THE
ATL METRO TAF SITES. EXPECT IT TO CLEAR THE AHN...CSG...AND MCN
AREAS BY 14Z. GUSTY NW WINDS WILL CONTINUE THROUGH MID
MORNING...THEN EXPECT SUSTAINED 8-12KT. WINDS DIMINISH OVERNIGHT.
VFR CONDITIONS BY THE AFTERNOON.
ATL CONFIDENCE...12Z UPDATE... LOW CONFIDENCE ON CIGS THROUGH
14Z...OTHERWISE HIGH CONFIDENCE.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 62 36 68 40 / 50 5 5 10
ATLANTA 61 39 66 43 / 10 5 5 10
BLAIRSVILLE 57 32 63 36 / 10 5 5 10
CARTERSVILLE 59 32 66 38 / 5 5 5 10
COLUMBUS 63 39 67 41 / 10 5 5 20
GAINESVILLE 61 38 65 40 / 10 5 5 10
MACON 65 34 68 40 / 60 5 5 10
ROME 59 31 65 36 / 5 5 5 10
PEACHTREE CITY 61 30 66 36 / 10 5 5 10
VIDALIA 70 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: EMANUEL...MONTGOMERY...TOOMBS.
&&
$$
SHORT TERM...20
LONG TERM....16
AVIATION...20
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1006 AM EST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT EASTWARD TONIGHT IN ADVANCE OF AN APPROACHING
COLD FRONT. THE COLD FRONT WILL SWEEP THROUGH THE AREA ON
FRIDAY...STALLING JUST OFFSHORE UNTIL STRONGER HIGH PRESSURE
BUILDS INTO THE AREA ON MONDAY. A LOW PRESSURE SYSTEM COULD
DEVELOP OFF THE SOUTHEAST COAST LATE TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
MORNING UPDATE...THE LINE OF THUNDERSTORMS HAS MOVED INTO THE FAR
INLAND COUNTIES. WARNINGS WILL BE ISSUED WITH MORE CAUTION SINCE
A LOT OF AREAS ARE MORE SUSCEPTIBLE TO WIND DAMAGE FROM THE RECENT
ICE STORM. RECENT TRENDS HAVE SHOWN A DECREASE IN LIGHTNING AS
PRECIPITABLE ECHOES ARE HOVERING NEAR OR BELOW 20K FT. SPC RUC
MESOANALYSIS INDICATES THAT CAPE VALUES ARE RANGING FROM 100 TO
500 J/KG...SO INSTABILITY IS STILL SOMEWHAT LACKING RIGHT NOW.
EXPECT THAT TO CHANGE AS THE DAY GOES ON AS SURFACE HEATING AND
FORCING INCREASES. UNTIL THEN...THE MAIN THREAT WILL BE STRONG TO
SEVERE WINDS AND ISOLATED TORNADOES. DAMAGE WAS CONFIRMED NEAR
DUBLIN IN LAURENS COUNTY WEST OF US. 6KM SHEAR WILL HOLD STEADY AT
NEARLY 45KTS...SO WE COULD SEE SOME BOWING SEGMENTS. IN TERMS OF
TIMING...ROUGH ESTIMATES ARE THAT THE LINE WILL BE NEAR SAV AT 16Z
AND CHS BY 17Z. MOST AREAS COULD SEE CLOSE TO 1.5 INCHES OF RAIN
ACCUMULATION WITH THE MORE INTENSE CELLS. TEMPERATURES WILL HOLD
STEADY IN THE LOW 70S TODAY FOR AREAS AHEAD OF THE COLD FRONT.
WITH FROPA...TEMPS COULD DROP 10 DEGREES.
PREVIOUS DISCUSSION...A STRONG MID LEVEL SHORT WAVE RIDING BELOW THE
LARGE/DEEP CLOSED UPPER LOW OVER THE GREAT LAKES WAS IMPRESSIVE
EARLY THIS MORNING ON WATER VAPOR SATELLITE IMAGERY. THIS FEATURE
WILL DIG THE MEAN UPPER TROUGH THROUGH THE TENNESSEE/OHIO VALLEYS
THIS MORNING THEN LIFT TOWARD NEW ENGLAND LATE TODAY. SUBTLE
NEGATIVE TILTING APPEARS TO BE STRONGER OFF TO THE NORTH OF OUR
FORECAST AREA THROUGH MID AFTERNOON.
ONGOING TRENDS THIS MORNING HAVE INCREASED OUR CONCERNS FOR SEVERE
WEATHER POTENTIAL IN THE PRE-FRONTAL ENVIRONMENT THROUGH MID
AFTERNOON. THE FIRST...OBVIOUSLY THE MUCH WARMER THAN GUIDANCE
READINGS THAT HAVE BECOME ROOTED ACROSS SE GEORGIA AND EASTERN SOUTH
CAROLINA EARLY THIS MORNING BEFORE DAYBREAK. ALTHOUGH TIMING OF
THE CONVECTIVE LINE THROUGH THE FORECAST AREA REMAINS FAIRLY
CONSISTENT FROM PREVIOUS MODEL RUNS TODAY...IT IS NOT GOING TO
TAKE MUCH TO ALLOW TEMPS TO RISE WARMER INTO THE LOWER TO MID 70S
THIS MORNING. UPSTREAM CONVECTION OVERNIGHT HAS BEEN QUITE
ROBUST WITH THE LATEST RAP SHOWING SURFACE BASED INSTABILITY INTO SW
GEORGIA WITH SBCAPES OVER 750 J/KG AT 08Z. SOME OF FORECAST AREAS
COULD SEE SOME THINNER CLOUDS THROUGH MID MORNING AS DENSE CLOUD
COVER WILL BE COMING IN LATER IN THE MORNING.
SPC HAS OUR REGION IN A SLIGHT RISK OF SEVERE CONVECTION AND THERE
APPEARS TO BE NO REASON TO DOUBT IT PER LATEST MESOSCALE TRENDS.
00Z HIGH RESOLUTION GUIDANCE INDICATING POTENTIAL FOR HIGHER DBZ CORES
AND LINEAR ORGANIZATION. GIVEN THE STRONG WIND FIELDS...SMALL BOWS
WOULD BE A CONCERN ALONG WITH POSSIBLE FORMATION OF A DECENT REAR
INFLOW JET. CONCERN FALLS OVER OUR NW TIER OF ZONES THAT SUFFERED
GREAT TIMBER DAMAGE FROM THE RECENT ICE STORM. TSTM GUST IMPACTS
COULD CERTAINLY BE MUCH GREATER IN THOSE ZONES WHERE WEAK AND
BROKEN LIMBS ALREADY LACE THAT REGION. EVEN A MARGINALLY GUSTY
SQUALL LINE COULD MAKE FOR SOME BAD TIMES IN SOME AREAS AND WE
WILL REMAIN COGNIZANT OF THIS SITUATION. WE WILL RAMP UP SEVERE
WORDING A BIT IN OUR HAZARDOUS WEATHER OUTLOOK THIS MORNING
ALTHOUGH IT IS STILL MORE LIKELY THAT WE ONLY SEE ONLY SEE
ISOLATED OCCURRENCES OF 50 KT CONVECTIVE WIND GUSTS IN THE
CONVECTIVE SEGMENTS/LINES AS TIMING AND STRENGTH OF DYNAMICS DO
NOT APPEAR TO COMPLETELY COME IN SYNC FOR A MORE WIDESPREAD
EVENT.
THE COLD FRONT WILL RACE THROUGH THE FORECAST AREA THIS AFTERNOON AND
OFFSHORE BY EARLY EVENING. MUCH COOLER TEMPS EXPECTED TONIGHT WITH
LOWS IN THE 40S AND GRADUALLY CLEARING SKIES.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
DRY HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY. AMPLE
MOISTURE WITHIN A 105 KT JET OVER THE DEEP SOUTH WILL PRODUCE
EXTENSIVE CIRRUS WHICH WILL SLIGHTLY LIMIT INSOLATION. HOWEVER HIGH
TEMPS WILL STILL REACH 70F IN MANY SPOTS.
ON SUNDAY WE START TO SEE SOME CHANNELED VORTICITY ENERGY MOVE INTO
THE EASTERN UNITED STATES. MEANWHILE THE LOW-LEVEL RIDGE OVER THE
WESTERN ATLANTIC STARTS TO SHIFT EAST AS THE FLOW BACKS TO
SOUTHWESTERLY. AS LOW-LEVEL MOISTURE INCREASES...WEAK ISENTROPIC
ASCENT WILL DEVELOP ACROSS SOUTHEAST GA WITH SOME RAIN SHOWERS
POSSIBLE BY SUNDAY AFTERNOON. WE ADDED A SLIGHT CHANCE OF TSTMS
ACROSS FAR SOUTHERN AREAS BECAUSE A POCKET OF ELEVATED INSTABILITY
SHIFTS THROUGH DURING THIS TIME. LOW-LEVEL WARM ADVECTION WILL PUSH
HIGH TEMPS INTO THE LOWER TO MIDDLE 70S.
A BACKDOOR COLD FRONT WILL DROP INTO THE AREA SUNDAY NIGHT AND PUSH
OFFSHORE ON MONDAY. UPPER DYNAMICS ARE NOT VERY IMPRESSIVE
ACCOMPANYING THE FROPA SO WE ONLY HAVE 20-40 POPS SUNDAY NIGHT.
ON MONDAY...SLIGHTLY COOLER HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WHILE THE BACKDOOR FRONT SITS JUST SOUTH OF THE AREA.
EXTENSIVE CLOUD COVER WILL ALSO PERSIST THOUGH THE BEST RAIN CHANCES
WILL BE FAR SOUTH CLOSER TO THE FRONT. WE SHOW HIGH TEMPS IN THE
MID/UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PATTERN WILL MAINLY BE DOMINATED BY A LOBE OF THE
POLAR VORTEX MOVING INTO THE GREAT LAKES REGION LATE WEEK. MONDAY
NIGHT THROUGH WEDNESDAY THE UPPER PATTERN WILL BE TRENDING TOWARD A
BROAD TROUGH REGIME WITH A SERIES OF WEAK FRONTS AND LOW PRESSURE
WAVES AFFECTING THE FORECAST AREA. DUE TO LARGE UNCERTAINTIES IN
TIMING INDIVIDUAL FEATURES WE MAINTAINED A CONSERVATIVE FORECAST
WITH MAINLY SLIGHT CHANCES FOR SHOWERS AND HIGH TEMPS IN THE 60S.
A STRONG COLD FRONT WILL SWEEP THROUGH WEDNESDAY NIGHT... FOLLOWED
BY COOL CANADIAN HIGH PRESSURE THURSDAY AND FRIDAY. THIS WILL BRING
DRY CONDITIONS AND BELOW-NORMAL TEMPERATURES.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
PRIOR TO THE RAINS TODAY...GUSTY SW SURFACE WINDS AHEAD OF THE
SQUALL LINE ALONG WITH FAIRLY WIDESPREAD MVFR CIGS. THERE COULD BE
A BRIEF BOUT OF IFR CIGS BUT THE WINDOW LOOKS FAIRLY BRIEF. ADDED
THUNDER TO THE TAFS WITH THE LINE EXPECTED TO BE OVER KSAV AROUND
16Z AND KCHS AT 17Z. THERE IS NOT A LOT OF LIGHTNING WITH THIS
LINE...BUT THAT COULD CHANGE AS INSTABILITY INCREASES. SKIES WILL
BEGIN TO CLEAR OUT THIS EVENING WITH VFR CONDITIONS EXPECTED
TONIGHT IN THE WAKE OF A COLD FRONT.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE AT KSAV SATURDAY
NIGHT AND AT BOTH TERMINALS SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE VFR.
&&
.MARINE...
A SEVERE TSTM WATCH IS IN EFFECT FOR NEAR SHORE WATERS AND THE
CHARLESTON HARBOR.
OTHERWISE...NOT MUCH MIXING GOING ON OVER CHILLY SHELF WATERS AND IT
IS INTERESTING TO SEE WINDS GUSTS TO 20 KT AT TIMES AT CHARLESTON
AND SAVANNAH WHERE TEMPS HAVE WARMED TO THE UPPER 60S. TEMPS AT
GRAYS REEF NEAR 60 AND WINDS BELOW 10 KT ALL NIGHT WITH 2-3 FT
SEAS...QUITE THE STRONG MARINE INVERSION. SEAS WILL CONTINUE TO BUILD
OFFSHORE AND MAINTAINED A MARGINAL SCA FOR CHARLESTON COUNTY
WATERS MAINLY WELL EAST OF BULLS BAY. MOST NEAR SHORE WATERS TODAY
WILL SEE SW WINDS 15 KT OR SO AND SEAS 3-4 FT TOPS. THERE IS ALSO
A SCA FOR OUR OUTER GEORGIA WATERS WITH OCCASIONALLY GUSTY SW FLOW
AND SEAS 4-7 FT...HIGHEST NEAR THE WEST WALL OF THE GULF STREAM.
THE FRONT MOVES THROUGH THIS EVENING WITH WINDS SHIFTING W OR WNW
TONIGHT WITH COLD AIR ADVECTION MORE GRADUAL THAN SHARP...CONDITIONS
BELOW SCA CRITERIA.
MARINE WINDS/SEAS WILL BE RATHER LIGHT SATURDAY THROUGH SUNDAY
BEFORE A COLD FRONT DROPS INTO THE WATER SUNDAY NIGHT. WINDS WILL
INCREASE ALONG THE FRONT BUT THE STRONGER SURGE COMES MONDAY AS THE
FLOW BECOMES NE. CONDITIONS COULD FLIRT WITH ADVISORY LEVELS...
ESPECIALLY MONDAY NIGHT WHEN SEAS COME UP SOME.
THE NEXT SURGE COMES WEDNESDAY AND WEDNESDAY NIGHT BEHIND A STRONG
COLD FRONT. MODERATE CHANCES FOR SMALL CRAFT ADVISORIES WITH THE
MID-WEEK SYSTEM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ350-
374.
&&
$$
SYNOPSIS...JRL
NEAR TERM...BDC
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...BDC
MARINE...BDC/JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
759 AM EST FRI FEB 21 2014
.UPDATE...
LINE OF CONVECTION/PRECIPITATION PROGRESSING QUICKLY ACROSS THE
FORECAST AREA. HAVE BEEN ABLE TO CLEAR SV.A 21. SV.A 22 REMAINS IN
EFFECT UNTIL 2 PM...HOWEVER THE PORTION IN OUR FORECAST AREA WILL
LIKELY BE CLEAR OF CONVECTION BY LATE MORNING AT THE CURRENT PACE.
POP AND SKY GRIDS LOOK GOOD WITH RESPECT TO CURRENT RADAR/SATELLITE
TRENDS SO NO MAJOR CHANGES PLANNED TO THE CURRENT GRIDS AT THIS TIME.
20
&&
.PREV DISCUSSION... /ISSUED 650 AM EST FRI FEB 21 2014/
PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
AVIATION...
12Z UPDATE...
AREA OF SHOWERS AND THUNDERSTORMS HAS ALMOST PUSHED EAST OF THE
ATL METRO TAF SITES. EXPECT IT TO CLEAR THE AHN...CSG...AND MCN
AREAS BY 14Z. GUSTY NW WINDS WILL CONTINUE THROUGH MID
MORNING...THEN EXPECT SUSTAINED 8-12KT. WINDS DIMINISH OVERNIGHT.
VFR CONDITIONS BY THE AFTERNOON.
ATL CONFIDENCE...12Z UPDATE... LOW CONFIDENCE ON CIGS THROUGH
14Z...OTHERWISE HIGH CONFIDENCE.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 100 5 5 10
ATLANTA 61 39 66 43 / 70 5 5 10
BLAIRSVILLE 57 32 63 36 / 60 5 5 10
CARTERSVILLE 61 32 66 38 / 40 5 5 10
COLUMBUS 63 39 67 41 / 80 5 5 20
GAINESVILLE 62 38 65 40 / 70 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 20 5 5 10
PEACHTREE CITY 61 30 66 36 / 70 5 5 10
VIDALIA 68 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BALDWIN...BLECKLEY...DODGE...EMANUEL...
GLASCOCK...HANCOCK...JEFFERSON...JOHNSON...LAURENS...
MONTGOMERY...PULASKI...TALIAFERRO...TELFAIR...TOOMBS...
TREUTLEN...TWIGGS...WARREN...WASHINGTON...WHEELER...WILCOX...
WILKES...WILKINSON.
&&
$$
SHORT TERM...20
LONG TERM....BDL
AVIATION...20
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
716 AM EST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT EASTWARD TONIGHT IN ADVANCE OF AN APPROACHING
COLD FRONT. THE COLD FRONT WILL SWEEP THROUGH THE AREA ON FRIDAY...STALLING
JUST OFFSHORE UNTIL STRONGER HIGH PRESSURE BUILDS INTO THE AREA ON
MONDAY. A LOW PRESSURE SYSTEM COULD DEVELOP OFF THE SOUTHEAST COAST
LATE TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEAR DAWN...FAIRLY ORGANIZED LINE OF CONVECTION MOVING IN FROM THE
WEST OVER EAST CENTRAL GEORGIA. A SEVERE THUNDERSTORM WATCH HAS BEEN
ISSUED FOR OUR ENTIRE FORECAST AREA AS TSTMS EXPECTED TO MOVE
THROUGH AT A DECENT CLIP. LATEST SPC RUC MESOANALYSIS INDICATES
MODERATE INSTABILITY BETWEEN 500 MB AND 700 MB WITH LAPSE RATES OF
-6.5C. THE LINE WILL BE MOVING INTO A SLIGHTLY LESS FAVORABLE
ENVIRONMENT OVER OUR INLAND GEORGIA ZONES IN THE NEXT COUPLE OF
HOURS...HOWEVER MUCH BETTER INSTABILITY IN PLACE OVER SE SOUTH
CAROLINA WITH SB LIFTED INDICES OF -3. LATEST HRRR FORECAST
CONVECTION PROGS SUGGEST SHOWERS AND STORMS COVERAGE AND INTENSITY
COULD INCREASE AFTER 15Z...THEN NEAR THE COAST AROUND MIDDAY.
A STRONG MID LEVEL SHORT WAVE RIDING BELOW THE LARGE/DEEP CLOSED UPPER
LOW OVER THE GREAT LAKES WAS IMPRESSIVE EARLY THIS MORNING ON WATER
VAPOR SATELLITE IMAGERY. THIS FEATURE WILL DIG THE MEAN UPPER TROUGH
THROUGH THE TENNESSEE/OHIO VALLEYS THIS MORNING THEN LIFT TOWARD NEW
ENGLAND LATE TODAY. SUBTLE NEGATIVE TILTING APPEARS TO BE STRONGER
OFF TO THE NORTH OF OUR FORECAST AREA THROUGH MID AFTERNOON.
ONGOING TRENDS THIS MORNING HAVE INCREASED OUR CONCERNS FOR SEVERE
WEATHER POTENTIAL IN THE PRE-FRONTAL ENVIRONMENT THROUGH MID
AFTERNOON. THE FIRST...OBVIOUSLY THE MUCH WARMER THAN GUIDANCE
READINGS THAT HAVE BECOME ROOTED ACROSS SE GEORGIA AND EASTERN SOUTH
CAROLINA EARLY THIS MORNING BEFORE DAYBREAK. ALTHOUGH TIMING OF
THE CONVECTIVE LINE THROUGH THE FORECAST AREA REMAINS FAIRLY
CONSISTENT FROM PREVIOUS MODEL RUNS TODAY...IT IS NOT GOING TO
TAKE MUCH TO ALLOW TEMPS TO RISE WARMER INTO THE LOWER TO MID 70S
THIS MORNING. UPSTREAM CONVECTION OVERNIGHT HAS BEEN QUITE
ROBUST WITH THE LATEST RAP SHOWING SURFACE BASED INSTABILITY INTO SW
GEORGIA WITH SBCAPES OVER 750 J/KG AT 08Z. SOME OF FORECAST AREAS
COULD SEE SOME THINNER CLOUDS THROUGH MID MORNING AS DENSE CLOUD
COVER WILL BE COMING IN LATER IN THE MORNING.
SPC HAS OUR REGION IN A SLIGHT RISK OF SEVERE CONVECTION AND THERE
APPEARS TO BE NO REASON TO DOUBT IT PER LATEST MESOSCALE TRENDS.
00Z HIGH RESOLUTION GUIDANCE INDICATING POTENTIAL FOR HIGHER DBZ CORES
AND LINEAR ORGANIZATION. GIVEN THE STRONG WIND FIELDS...SMALL BOWS
WOULD BE A CONCERN ALONG WITH POSSIBLE FORMATION OF A DECENT REAR
INFLOW JET. CONCERN FALLS OVER OUR NW TIER OF ZONES THAT SUFFERED
GREAT TIMBER DAMAGE FROM THE RECENT ICE STORM. TSTM GUST IMPACTS
COULD CERTAINLY BE MUCH GREATER IN THOSE ZONES WHERE WEAK AND
BROKEN LIMBS ALREADY LACE THAT REGION. EVEN A MARGINALLY GUSTY
SQUALL LINE COULD MAKE FOR SOME BAD TIMES IN SOME AREAS AND WE
WILL REMAIN COGNIZANT OF THIS SITUATION. WE WILL RAMP UP SEVERE
WORDING A BIT IN OUR HAZARDOUS WEATHER OUTLOOK THIS MORNING
ALTHOUGH IT IS STILL MORE LIKELY THAT WE ONLY SEE ONLY SEE
ISOLATED OCCURRENCES OF 50 KT CONVECTIVE WIND GUSTS IN THE
CONVECTIVE SEGMENTS/LINES AS TIMING AND STRENGTH OF DYNAMICS DO
NOT APPEAR TO COMPLETELY COME IN SYNC FOR A MORE WIDESPREAD
EVENT.
THE COLD FRONT WILL RACE THROUGH THE FORECAST AREA THIS AFTERNOON AND
OFFSHORE BY EARLY EVENING. MUCH COOLER TEMPS EXPECTED TONIGHT WITH
LOWS IN THE 40S AND GRADUALLY CLEARING SKIES.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
DRY HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY. AMPLE
MOISTURE WITHIN A 105 KT JET OVER THE DEEP SOUTH WILL PRODUCE
EXTENSIVE CIRRUS WHICH WILL SLIGHTLY LIMIT INSOLATION. HOWEVER HIGH
TEMPS WILL STILL REACH 70F IN MANY SPOTS.
ON SUNDAY WE START TO SEE SOME CHANNELED VORTICITY ENERGY MOVE INTO
THE EASTERN UNITED STATES. MEANWHILE THE LOW-LEVEL RIDGE OVER THE
WESTERN ATLANTIC STARTS TO SHIFT EAST AS THE FLOW BACKS TO
SOUTHWESTERLY. AS LOW-LEVEL MOISTURE INCREASES...WEAK ISENTROPIC
ASCENT WILL DEVELOP ACROSS SOUTHEAST GA WITH SOME RAIN SHOWERS
POSSIBLE BY SUNDAY AFTERNOON. WE ADDED A SLIGHT CHANCE OF TSTMS
ACROSS FAR SOUTHERN AREAS BECAUSE A POCKET OF ELEVATED INSTABILITY
SHIFTS THROUGH DURING THIS TIME. LOW-LEVEL WARM ADVECTION WILL PUSH
HIGH TEMPS INTO THE LOWER TO MIDDLE 70S.
A BACKDOOR COLD FRONT WILL DROP INTO THE AREA SUNDAY NIGHT AND PUSH
OFFSHORE ON MONDAY. UPPER DYNAMICS ARE NOT VERY IMPRESSIVE
ACCOMPANYING THE FROPA SO WE ONLY HAVE 20-40 POPS SUNDAY NIGHT.
ON MONDAY...SLIGHTLY COOLER HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WHILE THE BACKDOOR FRONT SITS JUST SOUTH OF THE AREA.
EXTENSIVE CLOUD COVER WILL ALSO PERSIST THOUGH THE BEST RAIN CHANCES
WILL BE FAR SOUTH CLOSER TO THE FRONT. WE SHOW HIGH TEMPS IN THE
MID/UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PATTERN WILL MAINLY BE DOMINATED BY A LOBE OF THE
POLAR VORTEX MOVING INTO THE GREAT LAKES REGION LATE WEEK. MONDAY
NIGHT THROUGH WEDNESDAY THE UPPER PATTERN WILL BE TRENDING TOWARD A
BROAD TROUGH REGIME WITH A SERIES OF WEAK FRONTS AND LOW PRESSURE
WAVES AFFECTING THE FORECAST AREA. DUE TO LARGE UNCERTAINTIES IN
TIMING INDIVIDUAL FEATURES WE MAINTAINED A CONSERVATIVE FORECAST
WITH MAINLY SLIGHT CHANCES FOR SHOWERS AND HIGH TEMPS IN THE 60S.
A STRONG COLD FRONT WILL SWEEP THROUGH WEDNESDAY NIGHT... FOLLOWED
BY COOL CANADIAN HIGH PRESSURE THURSDAY AND FRIDAY. THIS WILL BRING
DRY CONDITIONS AND BELOW-NORMAL TEMPERATURES.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
EARLIER CONCERNS WITH FOG HAS TURNED TO CONCERN FOR STRONG CONVECTION
MOVING INTO THE COASTAL CORRIDOR AFTER MID MORNING AND THEN
EXITING PRIOR TO MID AFTERNOON. PRIOR TO THE RAINS TODAY...GUSTY SW
SURFACE WINDS WERE DEVELOPING AHEAD OF THE SQUALL LINE ALONG WITH
FAIRLY WIDESPREAD MVFR CIGS. THERE COULD BE A BRIEF BOUT OF IFR CIGS
BUT THE WINDOW LOOKS FAIRLY BRIEF. STILL A BIT EARLY TO COMMIT TSRA
AS THE LINE COULD BE PREDOMINATELY MORE SHALLOW...HOWEVER WE BELIEVE
THUNDER WILL HAVE TO BE ADDED AT SOME POINT BY MID MORNING GIVEN
RADAR TRENDS. SKIES WILL BEGIN TO CLEAR OUT THIS EVENING WITH VFR
CONDITIONS EXPECTED TONIGHT IN THE WAKE OF A COLD FRONT.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE AT KSAV SATURDAY
NIGHT AND AT BOTH TERMINALS SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE VFR.
&&
.MARINE...
LITTLE TO NO REPORTS OF DENSE SEA FOG OVERNIGHT ALONG THE COAST WITH
SATELLITE IMAGERY ALSO NOT SUPPORTING OF FOG BASED LOW STRATUS OFF
THE COAST. THERE STILL IS A CHANCE FOR SEA FOG BUT GIVEN LATEST TRENDS
WE OPTED TO CANCEL MARINE FOG ADVISORIES AND JUST FORECAST PATCHY DENSE
FOG OVER THE WATERS THROUGH EARLY AFTERNOON WHEN RAIN CHANCES INCREASE
AND THE COLD FRONT NEARS. A SEVERE TSTM WATCH IS IN EFFECT FOR
NEAR SHORE WATERS AND THE CHARLESTON HARBOR.
OTHERWISE...NOT MUCH MIXING GOING ON OVER CHILLY SHELF WATERS AND IT
IS INTERESTING TO SEE WINDS GUSTS TO 20 KT AT TIMES AT CHARLESTON
AND SAVANNAH WHERE TEMPS HAVE WARMED TO THE UPPER 60S. TEMPS AT
GRAYS REEF NEAR 60 AND WINDS BELOW 10 KT ALL NIGHT WITH 2-3 FT
SEAS...QUITE THE STRONG MARINE INVERSION. SEAS WILL CONTINUE TO BUILD
OFFSHORE AND MAINTAINED A MARGINAL SCA FOR CHARLESTON COUNTY
WATERS MAINLY WELL EAST OF BULLS BAY. MOST NEAR SHORE WATERS TODAY
WILL SEE SW WINDS 15 KT OR SO AND SEAS 3-4 FT TOPS. THERE IS ALSO
A SCA FOR OUR OUTER GEORGIA WATERS WITH OCCASIONALLY GUSTY SW FLOW
AND SEAS 4-7 FT...HIGHEST NEAR THE WEST WALL OF THE GULF STREAM.
THE FRONT MOVES THROUGH THIS EVENING WITH WINDS SHIFTING W OR WNW
TONIGHT WITH COLD AIR ADVECTION MORE GRADUAL THAN SHARP...CONDITIONS
BELOW SCA CRITERIA.
MARINE WINDS/SEAS WILL BE RATHER LIGHT SATURDAY THROUGH SUNDAY
BEFORE A COLD FRONT DROPS INTO THE WATER SUNDAY NIGHT. WINDS WILL
INCREASE ALONG THE FRONT BUT THE STRONGER SURGE COMES MONDAY AS THE
FLOW BECOMES NE. CONDITIONS COULD FLIRT WITH ADVISORY LEVELS...
ESPECIALLY MONDAY NIGHT WHEN SEAS COME UP SOME.
THE NEXT SURGE COMES WEDNESDAY AND WEDNESDAY NIGHT BEHIND A STRONG
COLD FRONT. MODERATE CHANCES FOR SMALL CRAFT ADVISORIES WITH THE
MID-WEEK SYSTEM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ350-
374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
650 AM EST FRI FEB 21 2014
.PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
.AVIATION...
12Z UPDATE...
AREA OF SHOWERS AND THUNDERSTORMS HAS ALMOST PUSHED EAST OF THE
ATL METRO TAF SITES. EXPECT IT TO CLEAR THE AHN...CSG...AND MCN
AREAS BY 14Z. GUSTY NW WINDS WILL CONTINUE THROUGH MID
MORNING...THEN EXPECT SUSTAINED 8-12KT. WINDS DIMINISH OVERNIGHT.
VFR CONDITIONS BY THE AFTERNOON.
//ATL CONFIDENCE...12Z UPDATE...
LOW CONFIDENCE ON CIGS THROUGH 14Z...OTHERWISE HIGH CONFIDENCE.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 90 5 5 10
ATLANTA 61 39 66 43 / 70 5 5 10
BLAIRSVILLE 57 32 63 36 / 60 5 5 10
CARTERSVILLE 61 32 66 38 / 40 5 5 10
COLUMBUS 63 39 67 41 / 80 5 5 20
GAINESVILLE 62 38 65 40 / 70 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 20 5 5 10
PEACHTREE CITY 61 30 66 36 / 70 5 5 10
VIDALIA 68 45 70 46 / 90 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BALDWIN...BLECKLEY...DODGE...EMANUEL...
GLASCOCK...HANCOCK...JEFFERSON...JOHNSON...LAURENS...
MONTGOMERY...PULASKI...TALIAFERRO...TELFAIR...TOOMBS...
TREUTLEN...TWIGGS...WARREN...WASHINGTON...WHEELER...WILCOX...
WILKES...WILKINSON.
SEVERE THUNDERSTORM WATCH UNTIL 9 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: BIBB...CRAWFORD...CRISP...DOOLY...GREENE...
HOUSTON...JASPER...JONES...MACON...MARION...MONROE...MORGAN...
OGLETHORPE...PEACH...PUTNAM...SCHLEY...STEWART...SUMTER...
TAYLOR...WEBSTER.
&&
$$
SHORT TERM...31
LONG TERM....39
AVIATION...31
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
535 AM CST FRI FEB 21 2014
.DISCUSSION...
305 AM CST
TODAY...
POWERFUL STORM SYSTEM CONTINUES TO INFLUENCE THE WEATHER FOR THE
REGION TODAY...DESPITE THE SFC LOW BECOMING CENTERED WELL NORTH OF
THE FORECAST AREA THIS MORNING OVER NORTHERN WISCONSIN. A VERY TIGHT
GRADIENT REMAINS OVER NORTHERN IL/NORTHWEST IN...AS EARLY THIS
MORNING ISALLOBARIC PRES RISES HOVER ARND 5MB/3HR. THIS HAS BEEN
PRODUCING SUSTAINED WINDS BETWEEN 20-30MPH AND GUSTS AT TIMES TO 45
MPH. WILL MAINTAIN THE CURRENT WIND ADVISORY...HOWEVER BASED ON
LATEST GUIDANCE IT APPEARS GUSTS MAY BEGIN TO DIMINISH CLOSER TO
MIDDAY.
IR IMAGERY INDICATES THE DRY WEDGE HAS DEPARTED TO THE
NORTHEAST...WITH THE WRAP-AROUND MOISTURE BEGINNING TO SLIDE BACK
INTO NORTHERN IL/NORTHWEST IN. SFC OBS UPSTREAM EARLY THIS MORNING
HAVE INDICATED SOME LIGHT SNOW...AND A FEW POINTS IN CENTRAL IOWA
HAD VSBYS DOWN TO 1/4 MILE WITH MODERATE SNOW...HOWEVER FEEL THIS
MAY HAVE ACTUALLY BEEN A FUNCTION OF THE VERY GUSTY WINDS AND
AMPLIFYING THE EFFECTS SLIGHTLY. OVERALL THOUGH EXPECT THIS
WRAP-AROUND WEDGE TO SLOWLY SLIDE NORTHEAST...CLIPPING NORTHERN IL
THIS MORNING. THIS MAY PRODUCE A DUSTING OF SNOW...OTHERWISE BY LATE
MORNING FLURRIES SHOULD BE ALL THAT REMAINS BEFORE ENDING EARLY THIS
MORNING. TEMPS TODAY WILL BE CHAOTIC...WITH MORNING TEMPS MAINLY IN
THE 30S ACROSS THE REGION THEN FALLING INTO THE 20S. WITH CLOUD
COVER ERODING BY EARLY AFTN FROM SOUTHWEST TO NORTHEAST...THIS MAY
ALLOW TEMPS TO REBOUND A FEW DEGREES THIS AFTN. SO AS A RESULT HAVE
HELD ONTO HIGHS IN THE LOW/MID 30S WITH NEAR 40 ALONG THE FAR
SOUTHERN CWFA.
CONFIDENCE...HIGH.
TONIGHT THROUGH SUNDAY...
500MB TROUGH AXIS RETURNS TO THE REGION...WHICH PLACES A HOLD ON THE
PAST FEW DAYS OF ABNORMALLY WARM TEMPS AND BRINGS A REALITY CHECK
THAT WINTER IS STILL THE PREFERRED SEASON OF CHOICE BY MOTHER
NATURE. WITH THE POWERFUL SHORTWAVE STEADILY LIFTING NORTHEAST
TOWARDS JAMES BAY TONIGHT...THE TRAILING GRADIENT WILL WEAKEN. BROAD
SFC RIDGING IS POISED TO SLIDE EAST ACROSS THE TENN VALLEY
STRETCHING SOUTH TO THE GULF OF MEXICO. THIS WILL ALLOW THE FLOW
OVER OUR REGION TO MAINLY BE WESTERLY THROUGH TONIGHT AND INTO
SATURDAY.
GUIDANCE DIFFERS ON HOW TO RESOLVE A WEAK MID-LVL LOBE OF VORTICITY
THAT WILL MOVE EAST ACROSS THE CENTRAL PLAINS TOWARDS THE OHIO
VALLEY. THE FORCING LOOKS RATHER LOW WITH THIS FEATURE...HOWEVER A
SECONDARY SFC RIDGE OVER THE NORTHERN PLAINS WILL STRETCH SOUTHEAST
TOWARDS THE FORECAST AREA SAT NGT. AT THIS TIME HAVE HELD ONTO A DRY
FORECAST...HOWEVER COULD SEE FLURRIES BEING NEEDED AND PERHAPS A
SMALL WINDOW OF LIGHT SNOW SHOWERS INTO EARLY SUN MORNING.
THE 500MB TROUGH DOES NOT INDICATE ANY AMPLIFICATION THROUGH THE
WEEKEND...WHICH WILL LIKELY MAINTAIN A SEMI-ZONAL FLOW. THIS WILL
EXPEDITE PACIFIC WAVES REACHING THE FORECAST AREA/OHIO VALLEY IN AN
EFFICIENT MANNER. AS A RESULT GUIDANCE CONTINUES TO SUGGEST YET
ANOTHER WEAK MID-LVL LOBE OF VORTICITY ARRIVING SUN AFTN.
TEMPS TONIGHT WILL FALL INTO THE TEENS TO MID 20S...THEN WITH
P-CLOUDY SKIES SAT AND 850MB TEMPS HOVERING ARND -4 TO -6 DEG
C...HIGHS SAT SHOULD GENERALLY BE IN THE LOW 30S...POSSIBLY NEAR 40
FOR THE FAR SOUTHERN CWFA. WEAK FRONTAL BOUNDARY SLIDES OVER THE
AREA SUN...WITH WINDS TURNING NORTHWESTERLY AND BRINGING SLIGHTLY
COOLER AIR AS HIGHS ARE GENERALLY IN THE 20S.
CONFIDENCE IN TEMPS...MEDIUM/HIGH.
CONFIDENCE IN FLURRIES/LGT SNOW...MEDIUM.
MONDAY THROUGH FRIDAY...
ENSEMBLES HAVE CONTINUED TO POINT TOWARDS YET ANOTHER PATTERN CHANGE
BREWING IN THE EXTENDED PERIODS...WITH A HIGH-AMPLITUDE RIDGE
DEVELOPING OVER WESTERN CANADA OR THE YUKON. THE DOWNSTREAM RESULT
IS YET ANOTHER DEEP TROUGH DIGGING SOUTH THROUGH THE GREAT LAKES
REGION.
A WEAK MID-LVL WAVE WILL TRAVERSE THE REGION MON...WITH A PERIOD OF
LIGHT SNOW PROGGED TO BLANKET THE CWFA. THEN MOVING INTO TUE/WED...A
STRONGER FRONTAL BOUNDARY IS POISED TO SLIDE SOUTHEAST FROM CANADA
AND BRING 850MB THERMAL TROUGH OF -14 TO -20 DEG C TO THE REGION BY
WED...HOWEVER THIS MAY BE MILD COMPARED TO THE LATER PERIODS WHEN
GUIDANCE IS CURRENTLY SUGGESTING 850MB TEMPS BY LATE NEXT WEEK IN
THE -23 TO -28 DEG C RANGE. THIS WILL LIKELY ALLOW SFC TEMPS FOR THE
MIDDLE OF NEXT WEEK TO REMAIN IN THE TEENS...THEN POSSIBLY STRUGGLE
TO WARM BEYOND THE SINGLE DIGITS ABOVE ZERO BY THUR OF NEXT WEEK.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* VERY GUSTY WESTERLY WINDS.
* MVFR CIGS IMPROVING TO VFR LATE MORNING/EARLY AFTERNOON.
* LIGHT SNOW EARLY TO MID MORNING...WITH BLOWING SNOW.
BMD
//DISCUSSION...UPDATED 12Z...
A DEEP AREA OF LOW PRESSURE CURRENTLY OVER FAR NORTHERN WISCONSIN
CONTINUES TO LIFT AWAY FROM THE AREA...BUT STRONG WESTERLY WINDS ARE
FORECAST TO PERSIST MUCH OF THE DAY WITH GUSTS IN THE MID TO UPPER
30 KT RANGE THROUGH THE AFTERNOON...TAPERING INTO THE HIGH 20 TO LOW
30 KT RANGE THIS EVENING. MEANWHILE...AN UPPER LEVEL DISTURBANCE IS
DROPPING SOUTHEAST ACROSS THE MID/UPPER MISSISSIPPI VALLEY EARLY
THIS MORNING WITH SNOW SPREADING ACROSS NORTHERN ILLINOIS. VSBY IS
FALLING INTO THE 1-2SM RANGE AT TIMES WITH THE SNOW AND BLOWING
SNOW. THE WAVE SHOULD PASS WITH PRECIP ENDING MID TO LATE THIS
MORNING...AND WE MAY SEE LIGHT ACCUMULATIONS OF A FEW TENTHS. MVFR
CIGS WILL PERSIST THIS MORNING...BUT DRIER AIR MOVING IN SHOULD
SCOUR OUT SOME OF THE LOWER CLOUDS BY EARLY AFTERNOON WITH
CONDITIONS BECOMING VFR. WINDS WILL EASE THIS EVENING AND
TONIGHT...AND SHOULD REMAIN SW TO W.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN WIND DIRECTION...MEDIUM-HIGH CONFIDENCE IN
SPEED.
* MEDIUM-HIGH CONFIDENCE IN CIG TRENDS...MEDIUM IN TIMING
IMPROVEMENT TO VFR.
* LOW CONFIDENCE IN HOW AREAS OF SNOW WILL EVOLVE OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...CHC SNOW...ESPECIALLY LATE.
TUESDAY THROUGH THURSDAY...VFR.
BMD
&&
.MARINE...
302 AM CST
STRONG LOW PRESSURE LIES OVER WISCONSIN EARLY THIS MORNING AND WILL
LIFT NORTH ACROSS ONTARIO TO JAMES BAY BY LATE TONIGHT.
MEANWHILE...A TIGHT PRESSURE GRADIENT WILL RESULT IN STRONG GALES
AND STORM FORCE WINDS AT TIMES ACROSS LAKE MICHIGAN THROUGH THIS
AFTERNOON. WILL LEAVE THE CURRENT TIMING IN PLACE FOR THE STORM
WARNING...THOUGH LATEST PROJECTIONS INDICATE THAT IT MAY BE
CANCELED EARLY. EITHER WAY...A GALE WARNING WILL BE NEEDED TO
REPLACE THE STORM WARNING FOR A PERIOD LATE THIS AFTERNOON INTO
THE EARLY OVERNIGHT HOURS. WINDS SHOULD FINALLY DIMINISH BELOW
GALES LATE TONIGHT BUT WILL REMAIN AROUND 30 KT THROUGH THE
REMAINDER OF THE WEEKEND. A BROAD RIDGE OF HIGH PRESSURE WILL
BUILD FROM THE NORTHERN PLAINS INTO THE OHIO VALLEY AND REMAIN
ANCHORED FOR MUCH OF THE UPCOMING WEEK...LEAVING LAKE MICHIGAN
WITH PERSISTENT MODERATE WEST TO NORTHWEST WINDS NEXT WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-
ILZ032-ILZ033-ILZ039 UNTIL 3 PM FRIDAY.
IN...WIND ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 3 PM
FRIDAY.
LM...STORM WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM FRIDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 6
PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
350 AM CST Fri Feb 21 2014
.DISCUSSION...
ISSUED 323 AM CST Fri Feb 21 2014
Dynamic storm system moved through the region yesterday and
overnight with the main cold front well out to the east and the
occluded low center over nrn Wisconsin this morning. A small wave
rippling around this morning in the wake of the cold front
bringing some light snow and may continue through the morning
hours. Other than that, forecast is mainly a slow chill beyond
today and tomorrow as another push of cold air comes to the
Midwest. As far as precipitation, several shortwaves are hinted in
the models, but timing is not very consistent. Best consistency is
for Monday/Monday night, with the chance for accumulating snow.
Beyond Monday, temperatures fall below normals in the extended for
next week. At this point the forecast in the extended is dry, but
as it is also increasingly NWrly flow, expect to eventually see a
couple of short waves creep into the forecast.
SHORT TERM...Today and tomorrow...
A short break in the frigid temperatures as the max temps will
climb above freezing heading into the weekend. Clearing this
morning should result in a sunny afternoon, but clouds redevelop
for tomorrow so partly cloudy skies will keep temps from
increasing too much over todays max. Tonight and tomorrow night, a
quick shot for snow across the northern tier of the CWA as
shortwaves ripple through in the wake of the exiting low. Both
shots at precip should result in less than a half of an inch of
accumulation.
LONG TERM...Sunday through Thursday...
Relatively dry but beyond the weekend the operational models are
shearing out some energy across the center of the country and
setting up a weak boundary in parallel flow. Agreement btwn GFS
and ECMWF for the existence of a Monday/Monday night system, with
major issues with the timing. At the end of the NAM run, but the
NAM is leaning into the same solution. Just another quick shot of snow
with a clipper-like system from the WNW. Colder air moving in as
well, as flow amplifies and Midwest sees northwesterly flow
reestablish Tuesday night/Wednesday. Temperatures from midweek on
drop below seasonal normals again.
HJS
&&
.AVIATION...
ISSUED 1139 PM CST Thu Feb 20 2014
Strong W/SW winds will continue through the overnight hours,
although they will not be quite as strong as earlier this
evening. Based on latest obs and 00z numeric guidance, have
lowered winds into the 15 to 20kt range with gusts to between 25
and 30kt. The strong/gusty winds will continue through Friday as
well, before subsiding to around 10kt by evening. Main aviation
challenge will be an area of MVFR clouds currently pushing
eastward across Iowa/northern Missouri. Satellite timing tools
bring these clouds into KSPI by 08z, then further east to KCMI
between 09z and 10z. HRRR does not have a good handle on the
clouds, but at least hints at ceilings overnight into early Friday
morning. Have therefore cleared skies from west to east between
12z and 14z.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
527 AM CST FRI FEB 21 2014
.DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH TO SOUTHWEST WINDS WILL INCREASE AND BECOME GUSTY
AT ALL SITES BY 17Z. THESE WINDS WILL SUBSIDE AROUND 00Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 404 AM CST FRI FEB 21 2014/
DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 39 66 42 / 0 0 0 0
HOBART OK 68 38 70 41 / 0 0 0 0
WICHITA FALLS TX 71 43 76 47 / 0 0 0 0
GAGE OK 64 21 63 34 / 0 0 0 0
PONCA CITY OK 63 35 60 36 / 0 0 0 10
DURANT OK 65 44 70 52 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR OKZ005>030-033>040-044-045.
TX...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR TXZ083>090.
&&
$$
03/17/17
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
540 AM CST FRI FEB 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CST FRI FEB 21 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM ALASKA DOWN INTO THE MID-MISSISSIPPI
RIVER VALLEY AND A DEEP UPPER LOW OVER NORTHERN WI. UNDERNEATH THE
UPPER LOW WAS A 978 MB SURFACE LOW NEAR RHINELANDER. A VERY TIGHT
PRESSURE GRADIENT SOUTHWEST OF THE LOW WAS SUPPORTING SURFACE WINDS
OF 25 TO 35 MPH WITH GUSTS UP TO 55 MPH. THE COLD CONVEYOR BELT
WRAPPING AROUND THE NEARLY VERTICALLY STACKED LOW WAS STILL BRINGING
SNOW TO THE FORECAST AREA...HEAVIEST OVER NORTH CENTRAL WI. EARLIER
LAST EVENING THE STRONG WINDS WERE NOT REDUCING VISIBILITIES THAT
MUCH IN SOUTHEAST MN/NORTHEAST IA PER ASOS/AWOS OBSERVATIONS...DUE
TO THE WET NATURE OF THE SNOW. HOWEVER...CALLS TO COUNTY SHERIFFS
IN THE SAME AREA WERE REPORTING WHITEOUTS WITH SOME ROADS
CLOSED...SUGGESTING ASOS/AWOS OBSERVATIONS WERE NOT FULLY
REPRESENTATIVE. IN ADDITION...POWER OUTAGES WERE A MAJOR ISSUE
WITH THE WEIGHT OF THE WET SNOW ON TREES/POWER LINES AND WINDS.
NOW THE WINDS HAVE ADVECTED COLDER AIR INTO THE FORECAST AREA AS
NOTED BY TEMPERATURES IN THE TEENS TO LOW 20S. THE COLDER AIR HAS
ALLOWED THE SNOW TO BECOME DRIER...MORE ABLE TO BLOW.
THE NEARLY VERTICALLY STACKED LOW WILL CONTINUE LIFTING
NORTHEASTWARD OVER THE NEXT 24 HOURS...REACHING NORTHERN ONTARIO
THIS EVENING. AS THE LOW PULLS AWAY...THE WINDS WILL GRADUALLY
RELAX...DROPPING FROM 20 TO 35 MPH WITH HIGHER GUSTS DURING THE
MORNING TO 10 TO 25 MPH BY 00Z. FURTHER DIMINISHING OF THE WINDS ARE
EXPECTED TONIGHT. IN TERMS OF THE COLD CONVEYOR BELT OF SNOW...GOOD
AGREEMENT EXISTS THAT THE SNOW SHOULD EXIT MOST LOCATIONS WEST OF
THE MISSISSIPPI RIVER BY 12Z...LOCATIONS SOUTHWEST OF I-94 BY
18Z...AND THE CHIMNEY AREA BY 00Z. MUCH OF THE SNOW SHOULD BE
LIGHT WITH THE SYSTEM OCCLUDED AND MOVING AWAY. JUXTAPOSITION OF
THE WINDS AND SNOW SUGGESTS CONTINUATION OF HAZARDS OVER THE
NORTHWEST HALF OF THE FORECAST AREA. CONTEMPLATED RIGHT NOW
CANCELING SOME OF THE WINTER WEATHER ADVISORY...BUT HAVE KEPT IT
GOING FOR NOW DUE TO LIGHT SNOW GOING THROUGH AND STRONG WINDS
ALLOWING THAT TO BLOW AROUND...WINDS AT ADVISORY LEVEL...AND COLD
AIR ALLOWING RECENT WATER TO FREEZE.
WE SHOULD ALSO SEE SOME CLEARING TODAY SOUTHWEST TO NORTHEAST AS
DRIER/SUBSIDENT AIR OVER THE PLAINS ADVECTS IN BEHIND THE SYSTEM.
THIS CLEARING IS WELL EVIDENT OVER WESTERN IOWA AND FAR SOUTHWEST MN
CURRENTLY. THE DRIER AIR HOLDS INTO TONIGHT...SO ALTHOUGH SOME
SHORTWAVES ROTATING AROUND THE UPPER LOW ARE PROGGED TO COME ACROSS
THE FORECAST AREA...NO PRECIPITATION OR EVEN CLOUD IMPACTS ARE
EXPECTED FROM THEM.
925MB TEMPERATURES OF -8 TO -12C TODAY WILL RESULT IN MUCH COOLER
HIGHS TODAY COMPARED TO YESTERDAY...AS MUCH AS 15 TO 20 DEGREES
COLDER. 925MB TEMPS COOL EVEN MORE TONIGHT...TO -10 TO -16C BY 12Z
SATURDAY...COLDEST NORTH. HAVING MOSTLY CLEAR SKIES...COOLING TEMPS
AND FRESH SNOW IS CONCERNING FOR TEMPERATURES TO TANK...BUT MIXING
OF THE WINDS SHOULD HELP KEEP MOST LOCATIONS ABOVE 0F. THE LONE
EXCEPTION TO GO BELOW ZERO COULD BE UP IN TAYLOR COUNTY WHERE THE
COLDEST AIR IS FLOWING IN. COMBINATION OF THE WINDS AND FALLING
TEMPS BRINGS WIND CHILLS CLOSE BUT NOT TO -20F...WHEN WE WOULD ISSUE
WIND CHILL ADVISORIES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 214 AM CST FRI FEB 21 2014
MUCH OF THE LONG TERM PERIOD IS DOMINATED BY A STUCK UPPER LEVEL
PATTERN...RESULTING FROM AN OMEGA BLOCK THAT DEVELOPS AND
STRENGTHENS FROM ALONG THE U.S. WEST COAST INTO FAR WESTERN CANADA.
THE STRENGTHENING OMEGA BLOCK CORRELATES WELL WITH A STRATOSPHERIC
WARMING EVENT TAKING PLACE OVER THE ALEUTIANS THE NEXT FEW DAYS.
THIS OMEGA BLOCK WILL ALLOW A SERIES OF SHORTWAVE TROUGHS DROPPING
OUT OF THE ARCTIC TO COME THROUGH THE FORECAST AREA. IN THE WAKE OF
EACH TROUGH...A SURGE OF COLDER AIR WITH ARCTIC HIGH PRESSURE WILL
FOLLOW. GIVEN THE ARCTIC NATURE OF THE SHORTWAVES...MOISTURE AND
PRECIPITATION IS GOING TO BE HARD TO COME BY. THE ONLY REAL CHANCE
IT LOOKS LIKE FOR SNOW WILL COME MONDAY INTO MONDAY NIGHT WITH A
SHORTWAVE TROUGH DROPPING THROUGH THEN. STILL...AT THIS POINT...IT
DOES NOT APPEAR TO BE A BIG SNOW PRODUCER. HIGHEST CHANCES ARE
SITUATED OVER THE SOUTHWEST HALF OF THE FORECAST AREA.
NOW THE MAIN IMPACT ISSUE...THE COLD...WHICH HAS BEEN CONSISTENTLY
FORECASTED FROM THE ECMWF/GFS AND CFS. HAVING ARCTIC COLD FLOW INTO
THE FORECAST AREA ALSO CORRELATES WELL WITH THE AFOREMENTIONED
STRATOSPHERIC WARMING OVER THE ALEUTIANS.
THE WEEKEND...925MB TEMPS ARE NOT FORECAST TO CHANGE MUCH THROUGH
THE WEEKEND FROM THE -10 TO -16C PROGGED AT 12Z SATURDAY. THIS
SHOULD RESULT IN HIGHS SIMILAR FOR BOTH DAYS...RANGING FROM THE LOW
TEENS TO LOW 20S. TEMPERATURES SATURDAY NIGHT COULD FALL QUITE A BIT
WITH A WEAKER PRESSURE GRADIENT. TYPICAL COLD SPOTS WILL LIKELY
DECOUPLE...ALLOWING THEM TO APPROACH 10 BELOW. WIND CHILLS MAY FLIRT
WITH ADVISORY CRITERIA AS WELL SUNDAY MORNING.
NEXT WEEK...BEHIND THE MONDAY SHORTWAVE TROUGH...925MB TEMPS FALL TO
-18 TO -22C BY 12Z TUESDAY PER 21.00Z ECMWF/GFS. A COLDER SURGE
COMES IN TUESDAY NIGHT BEHIND ANOTHER SHORTWAVE TROUGH...WITH THOSE
925MB TEMPS DOWN TO -22 TO -26C AT 12Z WEDNESDAY. MORE IMPORTANTLY
WITH THIS COLD SURGE IS STRONGER 925MB WINDS OF 25-35 KTS...WHICH
RESULTS IN WIND CHILL ADVISORY NEED. THE FINAL AND COLDEST OF THE
COLD COMES WEDNESDAY NIGHT INTO THURSDAY. 925MB TEMPS ARE SIMILAR TO
THE TUESDAY NIGHT SURGE...BUT 850MB TEMPS APPROACH -30C IN TAYLOR
COUNTY...SUGGESTING A DEEPER COLDER AIRMASS. AND LIKE TUESDAY
NIGHT...PLENTY OF WIND IS FORECAST...SO WIND CHILL ADVISORY HAZARDS
LOOK LIKELY. IN FACT...LOWS THEMSELVES SHOULD BE IN THE SINGLE
DIGITS TO TEENS BELOW ZERO TUESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 540 AM CST FRI FEB 21 2014
THE STRONG LOW WAS ALREADY IN THE U.P. OF MI EARLY THIS MORNING...
CONTINUING TO MOVE AWAY FROM THE AREA. TAF SITES WERE ALREADY ON THE
EDGE OF THE TRAILING -SN...WHICH LOOKS TO BE OUT OF BOTH TAF SITES
BY 14Z. CIGS HAD GENERALLY COME UP TO THE 1500-2500FT RANGE...WITH
THE DECREASE OF CLOUDS/CLEARING LINE NEAR MANKATO MN TO JUST WEST OF
WATERLOO IA. BROUGHT THIS INTO/THRU THE TAF SITES AROUND 18Z...BUT
IT MAY OCCUR SOONER AT KRST.
BIGGEST REMAINING PROBLEM AT THE TAF SITES IS THE STRONG GRADIENT
WINDS BEHIND THE LOW WHICH WILL PERSIST ACROSS THE AREA TODAY.
THESE WINDS TO PRODUCE IFR/MVFR VSBYS IN BLSN AT SITES LIKE KRST
THRU MUCH OF THE MORNING. VSBYS AT KRST SHOULD GRADUALLY IMPROVE TO
MVFR BY LATE MORNING BUT WITH WINDS EXPECTED TO GUST 30-35KTS MVFR
VSBYS LOOK TO LINGER AT KRST MUCH OF THE AFTERNOON. WINDS DIMINISH
TO 15-20KTS THIS EVENING...WITH VFR CONDITIONS TONIGHT INTO SAT
MORNING AS COLDER/DRIER ARCTIC HIGH PRESSURE GRADUALLY BUILDS IN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR WIZ017-029-032>034.
MN...BLIZZARD WARNING UNTIL NOON CST TODAY FOR MNZ079-086-087-094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ096.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR MNZ088.
IA...BLIZZARD WARNING UNTIL NOON CST TODAY FOR IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR IAZ011-030.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
937 AM PST FRI FEB 21 2014
...UPDATED AVIATION SECTION...
.SYNOPSIS...
HIGH PRESSURE WILL BRING MOSTLY CLEAR SKIES AND ABOVE NORMAL MAXIMUM
TEMPERATURES THROUGH SATURDAY. THE MARINE LAYER WILL RETURN SUNDAY
AND BRING COOLER TEMPERATURES INTO EARLY NEXT WEEK. IT IS GROWING
MORE AND MORE LIKELY THAT IT WILL BE WET FROM MID WEEK ON.
&&
.SHORT TERM (TODAY-MON)...A DENSE FOG FIELD DEVELOPED OVER THE SAN
PEDRO CHANNEL THIS MORNING AND WAS EXPANDING OVER THE CHANNEL WHILE
SURGING NORTH OVER THE SANTA MONICA BASIN AT THIS TIME. THE LOW
LEVEL PROFILER IS INOP AT LAX THIS MORNING AND ESTIMATE THE TOPS
USING THE ABC LONG BEACH WEB CAM AT 500 FEET OR LESS. HRRR INDICATED
LIGHT SOUTH WINDS OVER THE SANTA MONICA BASIN THROUGH EARLY
AFTERNOON AND THE DENSE FOG MAY CONTINUE NORTH AND SURGE ONTO THE
MALIBU COAST LATE THIS MORNING. HAVE ISSUED AN UPDATE FOR THE LOS
ANGELES COUNTY COAST AND SANTA CATALINA ISLAND OTHERWISE NO CHANGES.
THE FOLLOWING DISCUSSION IS FROM THE PREVIOUS SHIFT...
A COUPLE OF NICE DAYS ON TAP TODAY AND SATURDAY AS THE AREA SITS
UNDER MOSTLY CLEAR SKIES. DRY SW FLOW WILL BE OVERHEAD AS A RIDGE
WILL SIT TO THE WEST OF THE STATE. GOOD OFFSHORE FLOW THIS MORNING
(WITH SOME RESULTANT SUB ADVISORY 15 TO 25 MPH WINDS THROUGH AND
BELOW THE CANYONS) WILL MAKE TODAY THE WARMEST WITH MANY VLY MAX
TEMPS IN THE LOW TO MID 80S. ON SATURDAY ONSHORE TRENDS COULD BRING
SOME LOW CLOUDS TO THE LONG BEACH AREA IN THE MORNING AND WILL COOL
THE COASTS BUT THE INTERIOR TEMPS WILL BE PRETTY UNCHANGED.
STRONGER ONSHORE FLOW ON SUNDAY AND A WEAK EDDY WILL BRING LOW
CLOUDS TO LA/VTA/SRN SBA COASTS AND LOCALLY INTO THE COASTAL VLYS.
THIS WILL CAUSE A GOOD COOL DOWN FOR THE COASTS AND VLY. THE MTNS
AND INTERIOR SECTIONS WILL NOT SEE MUCH CHANGE IN TEMPS.
MONDAY WILL BE A NEAR CARBON COPY (NOTHING LIKE AN OUT OF DATE
REFERENCE) OF SUNDAY. MORNING LOW CLOUDS FOR THE COASTS AND VLYS
SOUTH OF POINT CONCEPTION...OTHERWISE MOSTLY CLEAR SKIES WITH NEAR
NORMAL MAX TEMPS.
.LONG TERM (TUE-THU)...
THE XTND FCST IS WHERE ALL THE ACTION IS. ON TUESDAY THE RIDGE MOVES
EASTWARD. ONSHORE FLOW INCREASES. MID AND HIGH LEVEL CLOUDS WILL
STREAM IN AND BLANKET THE AREAS. A DEEP MARINE LAYER SHOULD BE LIFT
UP ACROSS THE CSTS AND INTO THE VLYS AS WELL. SO LOOK FOR A CLOUDIER
COOLER DAY.
CONTINUED CLOUDY ON WEDNESDAY WITH A BIG MIX OF LOW MID AND HIGH
CLOUDS. BY THE AFTERNOON A FRONT WILL APPROACH THE AREA. TIMING IS
NOT A SURE THING AS THE FRONT AND TROF WILL HAVE TO FIGHT THE
DEPARTING RIDGE AND MAY WELL BE SLOWED DOWN. THE CANADIAN MDL IS THE
FASTEST THE EC JUST A TOUCH SLOWER AND THE GFS IS NOTICEABLY SLOWER.
ALL THREE MDLS BRING RAIN TO THE CENTRAL COAST WED EVENING SO LIKELY
POPS SEEM JUSTIFIED EVEN THOUGH ITS STILL ALONG WAYS AWAY. A CHANCE
OF RAIN ELSE WHERE AS THE FRONT MOVES THROUGH THE AREA OVERNIGHT AND
INTO THURSDAY MORNING. HGTS ARE PRETTY HIGH AND SNOW LEVELS SHOULD
STAY ABOVE 6500 FEET.
CURRENT MDLS RUNS SHOW A SMALL POP UP RIDGE FOR THURSDAY AND A MUCH
LESS CHANCE OF RAIN. THE RIDGE SHOULD BE VERY DIRTY FROM THE
VANGUARD OF CLOUDS STREAMING AHEAD OF THE NEXT BIGGER SYSTEM SO
SKIES WILL LIKELY BE MOSTLY CLOUDY. STILL KEEP SLGT CHC/CHC POPS
GOING FOR THE DAY BECAUSE THE MDLS CAN EASILY MISS THE FCST BY 12
HOURS AND THERE COULD BE LINGERING SHOWERS OR EARLY ARRIVING SHOWERS.
THE BIG NEWS CONTINUES TO BE NEXT FRIDAY AND SATURDAY WITH ALL MDLS
CONTINUING TO FCST A SUBSTANTIAL STORM. YOU WILL WANT TO STAY TUNED
FOR THE LATEST UPDATES FOR THIS STORM AS IT DEVELOPS.
&&
.AVIATION...21/1730Z
HIGH CONFIDENCE IN VFR CONDITIONS AT MOST SITES FOR THE NEXT 24
HOURS DUE TO WEAK OFFSHORE FLOW. SOME DENSE FOG AND STRATUS HAS
FORMED ALONG THE LA COAST THIS MORNING...BUT NOT EXPECTING IT TO
REACH LAX OR LGB TODAY. THERE IS A 40 PERCENT CHANCE THAT LGB WILL
HAVE IFR CIGS OR LOWER SATURDAY MORNING.
KLAX...HIGH CONFIDENCE IN VFR CONDITIONS THROUGH ABOUT 11Z SATURDAY
MORNING. 20 PERCENT CHANCE OF IFR OR LOWER CIGS AFTER 12Z.
KBUR...HIGH CONFIDENCE IN VFR CONDITIONS FOR THE NEXT 24 HOURS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...30/RORKE
AVIATION...SUKUP
SYNOPSIS...SETO
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
855 AM PST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL BRING MOSTLY CLEAR SKIES AND ABOVE NORMAL MAXIMUM
TEMPERATURES THROUGH SATURDAY. THE MARINE LAYER WILL RETURN SUNDAY
AND BRING COOLER TEMPERATURES INTO EARLY NEXT WEEK. IT IS GROWING
MORE AND MORE LIKELY THAT IT WILL BE WET FROM MID WEEK ON.
&&
.SHORT TERM (TODAY-MON)...A DENSE FOG FIELD DEVELOPED OVER THE SAN
PEDRO CHANNEL THIS MORNING AND WAS EXPANDING OVER THE CHANNEL WHILE
SURGING NORTH OVER THE SANTA MONICA BASIN AT THIS TIME. THE LOW
LEVEL PROFILER IS INOP AT LAX THIS MORNING AND ESTIMATE THE TOPS
USING THE ABC LONG BEACH WEB CAM AT 500 FEET OR LESS. HRRR INDICATED
LIGHT SOUTH WINDS OVER THE SANTA MONICA BASIN THROUGH EARLY
AFTERNOON AND THE DENSE FOG MAY CONTINUE NORTH AND SURGE ONTO THE
MALIBU COAST LATE THIS MORNING. HAVE ISSUED AN UPDATE FOR THE LOS
ANGELES COUNTY COAST AND SANTA CATALINA ISLAND OTHERWISE NO CHANGES.
THE FOLLOWING DISCUSSION IS FROM THE PREVIOUS SHIFT...
A COUPLE OF NICE DAYS ON TAP TODAY AND SATURDAY AS THE AREA SITS
UNDER MOSTLY CLEAR SKIES. DRY SW FLOW WILL BE OVERHEAD AS A RIDGE
WILL SIT TO THE WEST OF THE STATE. GOOD OFFSHORE FLOW THIS MORNING
(WITH SOME RESULTANT SUB ADVISORY 15 TO 25 MPH WINDS THROUGH AND
BELOW THE CANYONS) WILL MAKE TODAY THE WARMEST WITH MANY VLY MAX
TEMPS IN THE LOW TO MID 80S. ON SATURDAY ONSHORE TRENDS COULD BRING
SOME LOW CLOUDS TO THE LONG BEACH AREA IN THE MORNING AND WILL COOL
THE COASTS BUT THE INTERIOR TEMPS WILL BE PRETTY UNCHANGED.
STRONGER ONSHORE FLOW ON SUNDAY AND A WEAK EDDY WILL BRING LOW
CLOUDS TO LA/VTA/SRN SBA COASTS AND LOCALLY INTO THE COASTAL VLYS.
THIS WILL CAUSE A GOOD COOL DOWN FOR THE COASTS AND VLY. THE MTNS
AND INTERIOR SECTIONS WILL NOT SEE MUCH CHANGE IN TEMPS.
MONDAY WILL BE A NEAR CARBON COPY (NOTHING LIKE AN OUT OF DATE
REFERENCE) OF SUNDAY. MORNING LOW CLOUDS FOR THE COASTS AND VLYS
SOUTH OF POINT CONCEPTION...OTHERWISE MOSTLY CLEAR SKIES WITH NEAR
NORMAL MAX TEMPS.
.LONG TERM (TUE-THU)...
THE XTND FCST IS WHERE ALL THE ACTION IS. ON TUESDAY THE RIDGE MOVES
EASTWARD. ONSHORE FLOW INCREASES. MID AND HIGH LEVEL CLOUDS WILL
STREAM IN AND BLANKET THE AREAS. A DEEP MARINE LAYER SHOULD BE LIFT
UP ACROSS THE CSTS AND INTO THE VLYS AS WELL. SO LOOK FOR A CLOUDIER
COOLER DAY.
CONTINUED CLOUDY ON WEDNESDAY WITH A BIG MIX OF LOW MID AND HIGH
CLOUDS. BY THE AFTERNOON A FRONT WILL APPROACH THE AREA. TIMING IS
NOT A SURE THING AS THE FRONT AND TROF WILL HAVE TO FIGHT THE
DEPARTING RIDGE AND MAY WELL BE SLOWED DOWN. THE CANADIAN MDL IS THE
FASTEST THE EC JUST A TOUCH SLOWER AND THE GFS IS NOTICEABLY SLOWER.
ALL THREE MDLS BRING RAIN TO THE CENTRAL COAST WED EVENING SO LIKELY
POPS SEEM JUSTIFIED EVEN THOUGH ITS STILL ALONG WAYS AWAY. A CHANCE
OF RAIN ELSE WHERE AS THE FRONT MOVES THROUGH THE AREA OVERNIGHT AND
INTO THURSDAY MORNING. HGTS ARE PRETTY HIGH AND SNOW LEVELS SHOULD
STAY ABOVE 6500 FEET.
CURRENT MDLS RUNS SHOW A SMALL POP UP RIDGE FOR THURSDAY AND A MUCH
LESS CHANCE OF RAIN. THE RIDGE SHOULD BE VERY DIRTY FROM THE
VANGUARD OF CLOUDS STREAMING AHEAD OF THE NEXT BIGGER SYSTEM SO
SKIES WILL LIKELY BE MOSTLY CLOUDY. STILL KEEP SLGT CHC/CHC POPS
GOING FOR THE DAY BECAUSE THE MDLS CAN EASILY MISS THE FCST BY 12
HOURS AND THERE COULD BE LINGERING SHOWERS OR EARLY ARRIVING SHOWERS.
THE BIG NEWS CONTINUES TO BE NEXT FRIDAY AND SATURDAY WITH ALL MDLS
CONTINUING TO FCST A SUBSTANTIAL STORM. YOU WILL WANT TO STAY TUNED
FOR THE LATEST UPDATES FOR THIS STORM AS IT DEVELOPS.
&&
.AVIATION...
21/1200Z
HI CONFIDENCE IN THE 12Z TAFS WITH VFR CONDITIONS EXPECTED AT ALL
THE AIRFIELDS FOR AT LEAST THE NEXT 18 HOURS. MARINE STRATUS COULD
DEVELOP OVER THE L.A. COAST AFTER 08Z SATURDAY.
KLAX...HI CONFIDENCE IN CAVU TAF THROUGH 08Z. THERE IS A 40 PERCENT
CHANCE OF LIFR CIGS AFTER 08Z.
KBUR...HI CONFIDENCE IN CAVU TAF.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...30/RORKE
AVIATION...KAPLAN
SYNOPSIS...SETO
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1005 AM MST FRI FEB 21 2014
.UPDATE...WINDS HAVE PICKED UP SOONER THAN EXPECTED AND HAVE
ALREADY UPDATED FOR THIS. ALSO LOWERED POPS AND SNOW AMOUNTS FOR
THE MOUNTAINS TODAY. WEB CAMERAS SHOWING THE SNOW IS CONFINED TO
THE HIGHER MOUNTAINS AND EXPECT THAT TREND TO CONTINUE THROUGH
TODAY. HIGHS LOOK ON TRACK...MAY NEED TO EVENTUALLY LOWER
TEMPERATURES A COUPLE OF DEGREES IF ANY ADJUSTMENTS ARE NEEDED.
&&
.AVIATION...STRONG WEST WINDS HAVE DEVELOPED AND WILL CONTINUE
UNTIL AROUND 00-01Z. GUSTS TO 40 TO 45 KNOTS WILL BE POSSIBLE AT
KDEN AND KAPA WITH GUSTS TO AROUND 50 KNOTS AT KBJC. WEST WINDS
WILL TURN SOUTHWEST DURING THE EVENING HOURS.
&&
.PREV DISCUSSION... /ISSUED 535 AM MST FRI FEB 21 2014/
UPDATE...
SHORT TERM...WINDS HAVE DROPPED OFF TO BLO WARNING LEVELS EVEN AT
THE NORMAL WINDY SPOTS SO WILL CANCEL THE HI WIND WARNING EARLY.
PREV DISCUSSION... /ISSUED 344 AM MST FRI FEB 21 2014/
SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA TODAY THRU
TONIGHT. DECENT WIND EVENT OCCURRED LATE LAST EVENING INTO THE
EARLY MORNING HOURS IN AND NEAR THE FOOTHILLS OF BOULDER AND
JEFFERSON COUNTIES AS GUSTS RANGED FROM 70-90 MPH. THE LAST FEW
HOURS WINDS HAVE DECREASED WITH GUSTS MAINLY IN THE 50-60 MPH
RANGE WITH A FEW GUSTS TO 70 MPH AT TIMES. OVERALL MTN WAVE SHOULD
BREAKDOWN BY 12Z WITH THREAT OF HIGH WINDS GRADUALLY BY 9 AM IF
NOT SOONER. HOWEVER IT STILL WILL BE VERY WINDY AT TIMES THROUGH
MIDDAY.
IN THE MTNS MOISTURE WAS INCREASING EARLY THIS MORNING AND COMBINED
WITH FAVORABLE OROGRAPHICS WAS PRODUCING SNOW IN THE MTNS WITH
AREAS OF BLOWING SNOW OVER THE HIGHER PASSES. MOISTURE IS FCST TO
DECREASE BY MIDDAY THRU THE EARLY EVENING HOURS SO SNOW COVERAGE
WILL LIKELY DECREASE BY 18Z ALTHOUGH AREAS OF BLOWING SNOW WILL
STILL BE POSSIBLE.
ACROSS NERN CO WITH RATHER STG NWLY FLOW IN THE LOWER LEVELS AS
MIXING OCCURS LATER THIS MORNING THRU THE AFTN HOURS WILL SEE
GUSTY NORTHWEST WINDS WITH SOME GUSTS IN THE 40-50 MPH RANGE AT
TIMES. AS FOR HIGHS WILL KEEP READINGS IN THE 45 TO 50 DEGREE
RANGE OVER THE PLAINS.
FOR TONIGHT MOISTURE MAY INCREASE IN THE MTNS AFTER MIDNIGHT WITH
BETTER COVERAGE OF SNOW ESPECIALLY NORTH OF I-70. WINDS WILL REMAIN
GUSTY IN THE MTNS AND FOOTHILLS HOWEVER CROSS MTN FLOW IS ONLY IN
THE 45-50 KT RANGE OVERNIGHT WITH A WEAKER MTN WAVE AS COMPARED
TO LAST NIGHT. THUS POTENTIAL FOR HIGH WINDS LOOKS ON THE LOW SIDE AT
THIS POINT HOWEVER STILL MAY SEE A FEW GUSTS TO 60-70 MPH AT TIMES
IN A FEW LOCATIONS.
LONG TERM...STRONG WESTERLY JET LEVEL FLOW IS PROGGED TO
CONTINUE OVER THE CWA SATURDAY INTO SUNDAY MORNING. FOR THE REST
TO SUNDAY AND SUNDAY NIGHT...THE FLOW ALOFT DECREASES A BIT AND IS
WEST-NORTHWESTERLY. THERE IS QG ASCENT PROGGED FOR THE CWA
SATURDAY INTO THE EARLY EVENING...THEN DOWNWARD MOTION IS PROGGED
WELL INTO SUNDAY. THERE IS WEAK UPWARD TO NEUTRAL SYNOPTIC SCALE
ENERGY FOR SUNDAY NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS
POINT TO NORMAL DIURNAL PATTERNS FOR WINDS SATURDAY. MODELS DO
NOT BRING THE COLD FRONT INTO THE CWA UNTIL LATE AFTERNOON/EARLY
EVENING. UPSLOPE IS PROGGED ALL OF SATURDAY NIGHT...WITH
SOUTHEASTERLIES ON SUNDAY. TROUGHING IS PROGGED TO DEVELOP EAST OF
THE MOUNTAINS SUNDAY NIGHT...AND ENHANCED DRAINAGE WIND PATTERNS
CAN BE EXPECTED FOR THE PLAINS AND FOOTHILLS. FOR MOISTURE...
THERE IS SOME OVER THE MOUNTAINS ON SATURDAY...AND LITTLE OVER THE
PLAINS. IT IS A BIT DEEPER OVER THE MOUNTAINS SATURDAY NIGHT...
WITH A BIT AT THE LOWER LEVELS FOR THE PLAINS. THERE IS SOME
MOISTURE HANGING AROUND OVER THE MOUNTAINS SUNDAY AND SUNDAY
NIGHT...WITH A BIT OVER THE PLAINS IN THE MORNING ONLY. OVERALL
.MOISTURE IS LESS ON THESE 00Z MODEL RUNS COMPARED TO
YESTERDAY`S. THE QPF FIELDS HAVE SMALL AMOUNTS OF MEASURABLE
SNOWFALL OVER THE MOUNTAINS SATURDAY THROUGH ABOUT MID DAY SUNDAY.
THERE IS A TAD OVER THE PLAINS...MOSTLY THE NORTHERN HALF...
SATURDAY AFTERNOON LATE INTO SUNDAY MORNING. FOR POPS WILL GO WITH
40-70%S IN THE MOUNTAINS SATURDAY AND SATURDAY NIGHT. WILL GO WITH
"CHANCE"S OVER THE NORTHERN HALF OF THE PLAINS SATURDAY NIGHT.
WINDS SHOULD BE BE PARTICULARLY STRONG. THERE WILL BE SOME
DECREASING POPS OVER THE MOUNTAINS AND NORTHEAST CORNER ON SUNDAY.
SUNDAY NIGHT SHOULD BE DRY. FOR TEMPERATURES...SATURDAY`S HIGHS
SHOULD ONLY BE A TAD COLDER THAN TODAY`S...ESPECIALLY SINCE THE
COLD FRONT IS PROGGED IN LATE DAY. SUNDAY`S HIGHS ARE 1-3 C COLDER
THAN SATURDAY`S. FOR THE LATER DAYS...MONDAY THROUGH THURSDAY...
WEAKER WEST-NORTHWESTERLY FLOW IS PROGGED MONDAY INTO TUESDAY. A
WEAK UPPER TROUGH SLIDES IN FROM THE NORTHWEST LATER TUESDAY AND
TUESDAY NIGHT WITH AN ASSOCIATED COLD FRONT. TUESDAY LOOKS TO HAVE
BETTER POPS FOR ALL THE CWA THAN PREVIOUS MODELS INDICATED. THE
WEST-NORTHWESTERLY FLOW ALOFT CONTINUES ON WEDNESDAY AND
THURSDAY. THERE IS AN UPPER RIDGE AXIS JUST WEST OF THE CWA ON
THURSDAY.
AVIATION...WNW WINDS WERE ALREADY OCCURRING AT DIA WITH GUSTS
TO 25 MPH AT TIMES EARLY THIS MORNING. BOTH THE HRRR AND RAP SHOW
GUSTY WNW WINDS THRU 00Z WITH SOME GUSTS TO 40 MPH AT TIMES.
AFTER 00Z WINDS MAY BECOME MORE WLY WITH SPEEDS IN THE 10-20 MPH
RANGE WHICH WILL GRADUALLY BECOME MORE SSW AFTER 03Z. OTHERWISE
EXPECT VFR CONDITIONS TODAY THRU TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
UPDATE/AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS ALBANY NY
105 PM EST FRI FEB 21 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...ACCOMPANIED BY A
PERIOD OF RAIN SHOWERS WITH SOME DOWNPOURS AND ISOLATED THUNDER.
BEHIND THE FRONT...DRIER AIR WILL FILTER INTO THE REGION TONIGHT.
THE AIR MASS BEHIND THE COLD FRONT WILL STILL BE RELATIVELY
MILD...SO ABOVE NORMAL TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH
MUCH OF THE WEEKEND. MUCH COLDER AIR WILL MOVE INTO THE REGION NEXT
WEEK.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1245 PM...TEMPERATURES CONTINUE TO ONLY SLOWLY RISE IN MOST
AREAS EARLY THIS AFTERNOON DUE TO DEEP SNOWPACK AND NORTHERLY
AGEOSTROPHIC WIND COMPONENT. MANY LOCATIONS STILL HAVE
TEMPERATURES IN THE MID TO UPPER 30S...ALTHOUGH HIGHER TERRAIN
AREAS TO THE WEST AND EAST OF ALBANY HAVE WARMED INTO THE 40S WITH
EVEN A POCKET OF LOWER 50S IN PARTS OF SCHOHARIE COUNTY. WE ARE
EXPECTING A BRIEF SPIKE IN TEMPS IN THE UPPER 30S TO MID 40S
IMMEDIATELY PRECEDING THE COLD FRONT...WHICH AS OF NOON WAS
PROGRESSING EASTWARD THROUGH CENTRAL NY/PA. THE FRONT SHOULD
CONTINUE TO MAKE STEADY PROGRESS EASTWARD AS THERE ARE GOOD
PRESSURE RISES BEHIND THE FRONT.
THE COLD FRONT IS STILL EXPECTED TO MOVE FROM WEST TO EAST ACROSS
THE AREA DURING THE MID TO LATE AFTERNOON HOURS. A STRONGLY
FORCED LINE OF SHOWERS WITH DOWNPOURS...AND POSSIBLY ISOLATED
THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS SCENARIO IS STILL
BEING WELL-DEPICTED BY THE HRRR AND LOCAL HIRES WRF AS
WELL. TIMING LOOKS TO BE BASICALLY FROM 1 PM THROUGH 6 PM.
SHOWALTER VALUES LOOK TO BE JUST BELOW ZERO...SO SOME ELEVATED
INSTABILITY IS POSSIBLE FOR A RUMBLE OR TWO OF THUNDER...BUT NO
STRONG/SEVERE STORMS ARE ANTICIPATED DUE TO MEAGER SURFACE BASED
INSTABILITY. ONCE THE FRONT GOES THROUGH...THE THREAT FOR SHOWERS
WILL DIMINISH GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION AT
SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY QPF
WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER QUICKLY.
WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH EXPECTED
COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE SNOW...PERHAPS
MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR VALLEY AREAS. JUST AN
INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR NOW...WILL JUST GO WITH CHC
POPS FOR SUN/SUN NIGHT DUE TO UNCERTAINTY REGARDING ITS EXACT
TRACK/TIMING. MAX TEMPS WILL BE IN THE 30S...AND MINS SUNDAY NIGHT
LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THE 2 TO 3 HOUR BAND OF RAIN ASSOCIATED WITH COLD FRONT THAT WILL
MOVE THROUGH THE REGION THIS AFTERNOON...WILL BEGIN TO AFFECT THE
TAF SITES BETWEEN 19Z AND 20Z...AND THEN DEPART BETWEEN 22Z AND 23Z.
WITH IFR/MVFR CONDITONS ALREADY OCCURRING AHEAD OF THIS
RAINFALL...HAVE FORECAST IFR/MVFR CONDITIONS AT THE TAF SITES
THROUGH 22Z-23Z. AFTER 23Z DRIER AIR WILL MOVE IN AND CIGS MAY
REMAIN MVFR FOR SEVERAL MORE HOURS...THEN EXPECT SKIES TO BECOME
MAINLY CLEAR AFTER MIDNIGHT AT ALL THE TAF SITES.
WINDS WILL BE LIGHT AND VARIABLE AT THE TAF SITES EXPECT FOR KALB
WHERE WINDS WILL BE SOUTH AT AROUND 10 KTS WITH GUSTS OF AROUND 15
KTS. BEHIND THE FRON THE WINDS WILL BECOME WEST OR SOUTHWEST AT 5 TO
10 KTS...BUT GUST UP TO 15 TO 18 KTS AT KALB AND KPSF. THE WINDS
WILL DECREASE OVERNIGHT...BUT THEN PICK UP AGAIN FROM THE SOUTHWEST
AT 08 TO 14 KTS BY MID MORNING SATURDAY...WITH GUSTS ABOVE 20 KTS...
ESPECIALLY AT KALB.
OUTLOOK...
SATURDAT AFTERNOON AND NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: LOW OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND CONTINUES TO GENERALLY RANGE FROM 10 TO 30 INCHES...WITH
SOME HIGHER AMOUNTS IN THE MOUNTAINS. NOT MUCH SNOW MELT OCCURRED
OVERNIGHT INTO THIS MORNING DUE TO TEMPERATURES REMAINING IN THE 30S.
TEMPERATURES HAVE BEEN SLOW TO WARM TODAY...WITH HIGHS EXPECTED TO
BE IN THE UPPER 30S TO MID 40S THIS AFTERNOON. MORE RAIN WILL OCCUR
THIS AFTERNOON AHEAD OF AND ALONG A COLD FRONT PASSING THROUGH FROM
WEST TO EAST. THERE WILL LIKELY BE SOME DOWNPOURS...WHICH COMBINED
WITH SNOWPACK...COULD CAUSE PONDING AND/OR MINOR FLOODING OF URBAN
AREAS AND POOR DRAINAGE LOCATIONS DUE TO CLOGGED STORM DRAINS.
STORM TOTAL QPF STILL EXPECTED TO BE A HALF INCH TO NEARLY ONE AND A
HALF INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DRIER AIR WILL QUICKLY RETURN BEHIND THE COLD FRONT TONIGHT...WITH
TEMPERATURES DROPPING BACK BELOW FREEZING ACROSS THE ENTIRE REGION
BY EARLY SATURDAY MORNING. DAYTIME TEMPERATURES OVER THE WEEKEND
WILL CONTINUE TO BE ABOVE FREEZING...AND OVERNIGHT LOWS WILL DROP
BELOW FREEZING THIS WEEKEND. THIS SHOULD ALLOW FOR A STEADY
CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY FLOODING CONCERNS. MUCH
COLDER WEATHER...WITH TEMPERATURES COMPLETELY BELOW FREEZING...WILL
RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION POTENTIAL FOR ISOLATED ICE JAMS ON
SMALLER STREAMS AND CREEK IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY
INTO TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT
WIDESPREAD FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV
NEAR TERM...FRUGIS/GJM/JPV
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...GJM
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1246 PM EST FRI FEB 21 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...ACCOMPANIED BY A
PERIOD OF RAIN SHOWERS WITH SOME DOWNPOURS AND ISOLATED THUNDER.
BEHIND THE FRONT...DRIER AIR WILL FILTER INTO THE REGION TONIGHT.
THE AIR MASS BEHIND THE COLD FRONT WILL STILL BE RELATIVELY
MILD...SO ABOVE NORMAL TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH
MUCH OF THE WEEKEND. MUCH COLDER AIR WILL MOVE INTO THE REGION NEXT
WEEK.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1245 PM...TEMPERATURES CONTINUE TO ONLY SLOWLY RISE IN MOST
AREAS EARLY THIS AFTERNOON DUE TO DEEP SNOWPACK AND NORTHERLY
AGEOSTROPHIC WIND COMPONENT. MANY LOCATIONS STILL HAVE
TEMPERATURES IN THE MID TO UPPER 30S...ALTHOUGH HIGHER TERRAIN
AREAS TO THE WEST AND EAST OF ALBANY HAVE WARMED INTO THE 40S WITH
EVEN A POCKET OF LOWER 50S IN PARTS OF SCHOHARIE COUNTY. WE ARE
EXPECTING A BRIEF SPIKE IN TEMPS IN THE UPPER 30S TO MID 40S
IMMEDIATELY PRECEDING THE COLD FRONT...WHICH AS OF NOON WAS
PROGRESSING EASTWARD THROUGH CENTRAL NY/PA. THE FRONT SHOULD
CONTINUE TO MAKE STEADY PROGRESS EASTWARD AS THERE ARE GOOD
PRESSURE RISES BEHIND THE FRONT.
THE COLD FRONT IS STILL EXPECTED TO MOVE FROM WEST TO EAST ACROSS
THE AREA DURING THE MID TO LATE AFTERNOON HOURS. A STRONGLY
FORCED LINE OF SHOWERS WITH DOWNPOURS...AND POSSIBLY ISOLATED
THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS SCENARIO IS STILL
BEING WELL-DEPICTED BY THE HRRR AND LOCAL HIRES WRF AS
WELL. TIMING LOOKS TO BE BASICALLY FROM 1 PM THROUGH 6 PM.
SHOWALTER VALUES LOOK TO BE JUST BELOW ZERO...SO SOME ELEVATED
INSTABILITY IS POSSIBLE FOR A RUMBLE OR TWO OF THUNDER...BUT NO
STRONG/SEVERE STORMS ARE ANTICIPATED DUE TO MEAGER SURFACE BASED
INSTABILITY. ONCE THE FRONT GOES THROUGH...THE THREAT FOR SHOWERS
WILL DIMINISH GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION AT
SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY QPF
WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER QUICKLY.
WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH EXPECTED
COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE SNOW...PERHAPS
MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR VALLEY AREAS. JUST AN
INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR NOW...WILL JUST GO WITH CHC
POPS FOR SUN/SUN NIGHT DUE TO UNCERTAINTY REGARDING ITS EXACT
TRACK/TIMING. MAX TEMPS WILL BE IN THE 30S...AND MINS SUNDAY NIGHT
LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
MUCH OF THE RAIN HAS ENDED AT LEAST FOR NOW AT THE TAF SITES WITH
THE NEXT BATCH OF RAIN AHEAD OF THE COLD FRONT NOT EXPECTED TO
ARRIVE UNTIL EARLY AFTERNOON. THE TAF SITES UP UNTIL THIS TIME ARE
EXPECTED TO BE MVFR AT KGFL AND KALB WITH IFR/LIFR CONDITIONS
EXPECTED AT KPSF AND KPOU WHERE FOG AND LOW STRATUS WL BE PRESENT.
IFR CONDITIONS ARE EXPECTED AT ALL OF THE TAF SITES STARTING ARND
18Z AS THE NEXT BATCH OF RAIN MOVES IN. A COLD FRONT WL SWEEP
THROUGH THE RGN LATE THIS AFTERNOON WITH SKIES BECOMING SKC THIS
EVENING IN THE WAKE OF THE COLD FRONT.
WINDS WILL BE LIGHT AND VARIABLE UNTIL EARLY AFTERNOON AND THEN
NE-SE ARND 5 KTS AHD OF THE FRONT AND WEST TO SOUTHWEST AT 6 TO 10
KTS IN THE WAKE OF THE COLD FRONT.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND CONTINUES TO GENERALLY RANGE FROM 10 TO 30 INCHES...WITH
SOME HIGHER AMOUNTS IN THE MOUNTAINS. NOT MUCH SNOW MELT OCCURRED
OVERNIGHT INTO THIS MORNING DUE TO TEMPERATURES REMAINING IN THE 30S.
TEMPERATURES HAVE BEEN SLOW TO WARM TODAY...WITH HIGHS EXPECTED TO
BE IN THE UPPER 30S TO MID 40S THIS AFTERNOON. MORE RAIN WILL OCCUR
THIS AFTERNOON AHEAD OF AND ALONG A COLD FRONT PASSING THROUGH FROM
WEST TO EAST. THERE WILL LIKELY BE SOME DOWNPOURS...WHICH COMBINED
WITH SNOWPACK...COULD CAUSE PONDING AND/OR MINOR FLOODING OF URBAN
AREAS AND POOR DRAINAGE LOCATIONS DUE TO CLOGGED STORM DRAINS.
STORM TOTAL QPF STILL EXPECTED TO BE A HALF INCH TO NEARLY ONE AND A
HALF INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DRIER AIR WILL QUICKLY RETURN BEHIND THE COLD FRONT TONIGHT...WITH
TEMPERATURES DROPPING BACK BELOW FREEZING ACROSS THE ENTIRE REGION
BY EARLY SATURDAY MORNING. DAYTIME TEMPERATURES OVER THE WEEKEND
WILL CONTINUE TO BE ABOVE FREEZING...AND OVERNIGHT LOWS WILL DROP
BELOW FREEZING THIS WEEKEND. THIS SHOULD ALLOW FOR A STEADY
CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY FLOODING CONCERNS. MUCH
COLDER WEATHER...WITH TEMPERATURES COMPLETELY BELOW FREEZING...WILL
RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION POTENTIAL FOR ISOLATED ICE JAMS ON
SMALLER STREAMS AND CREEK IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY
INTO TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT
WIDESPREAD FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV
NEAR TERM...FRUGIS/GJM/JPV
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...GJM
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
110 PM EST FRI FEB 21 2014
UPDATE...
A LINE OF SHOWERS AND TSTMS FROM SWAINSBORO TO LUMBER CITY
CONTINUES MOVING EAST THROUGH THE REMAINDER OF THE FFC FORECAST
AREA. MOST OF THE FFC GA COUNTIES HAVE BEEN REMOVED FROM THE
SVR TSTM WATCH 22. THE REMAINING THREE COUNTIES WILL BE REMOVED
BY 1100 PM EST. THE COLD FRONT EXTENDING FROM WARRENTON TO CORDELE
WILL EXIT THE FORECAST AREA BY EARLY AFTERNOON. RAPID CLEARING
WILL CONTINUE ACROSS NORTH AND CENTRAL GEORGIA THROUGH THE DAY.
16
PREV DISCUSSION... /ISSUED 650 AM EST FRI FEB 21 2014/
PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A
FEW HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
AVIATION...
18Z UPDATE...
SMALL AREA OF IFR/MVFR CEILINGS IN THE SOUTHEAST CORNER OF THE
FORECAST AREA AT THIS TIME...WELL SOUTHEAST OF THE TAF SITES...WILL
IMPROVE TO VFR BY 20Z WITH VFR CONDITIONS EXPECTED AREAWIDE THROUGH
THE REMAINDER OF THIS FORECAST PERIOD. COLD FRONT HAS CLEARED THE
FORECAST AREA WITH NORTHWEST WINDS EXPECTED TO CONTINUE AREAWIDE
THROUGH 12-15Z SATURDAY...BECOMING NORTHEASTERLY AND EVENTUALLY
SOUTHEASTERLY 15-00Z. WIND SPEEDS REMAIN 8-14KTS CURRENTLY WITH
FREQUENT GUSTS 15-23KT BUT WILL CONTINUE TO DIMINISH...DROPPING TO
6-8KT BY 00Z AND 2-5KT BY 00Z. WIND SPEEDS WILL INCREASE AFTER 12Z
SATURDAY...REACHING 4-8KT BY 18Z.
ATL CONFIDENCE...18Z UPDATE...
HIGH.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 62 36 68 40 / 50 5 5 10
ATLANTA 61 39 66 43 / 10 5 5 10
BLAIRSVILLE 57 32 63 36 / 10 5 5 10
CARTERSVILLE 59 32 66 38 / 5 5 5 10
COLUMBUS 63 39 67 41 / 10 5 5 20
GAINESVILLE 61 38 65 40 / 10 5 5 10
MACON 65 34 68 40 / 60 5 5 10
ROME 59 31 65 36 / 5 5 5 10
PEACHTREE CITY 61 30 66 36 / 10 5 5 10
VIDALIA 70 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: EMANUEL...MONTGOMERY...TOOMBS.
&&
$$
SHORT TERM...20
LONG TERM....16
AVIATION...20
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
910 AM MST FRI FEB 21 2014
.UPDATE...
CURRENT FORECAST LOOKS TO BE IN GOOD SHAPE BUT HAVE MADE A FEW
ADJUSTMENTS WITH THIS MORNINGS UPDATE. RADAR CURRENTLY SHOWING
NUMEROUS SNOW SHOWERS DEVELOPING ALONG THE BEARTOOTH FOOTHILLS AND
PRYOR MOUNTAINS WITH SOME NARROW NORTHWEST TO SOUTHEAST SNOW BANDS
FROM AROUND BILLINGS WESTWARD TO THE FOOTHILLS. HAVE RAISED POPS
TO LIKELY FOR THE ENTIRE DAY AS HRRR MODELS SHOWING AREAS OF
SNOWBANDS THROUGHOUT THE DAY ACROSS OUR CENTRAL AND WESTERN
LOCATIONS. EXPECT SCATTERED SNOW SHOWERS EAST OF BILLINGS WITH
MORE NUMEROUS SNOW SHOWERS FROM BILLINGS WESTWARD. ACCUMULATIONS
ARE EXPECTED TO BE GENERALLY LESS THAN AN INCH BUT AREAS THAT ARE
UNDER ANY TRAINING SNOW BANDS MAY PICK UP A QUICK INCH OR TWO.
WILL BE MONITORING THESE SNOW BANDS THROUGHOUT THE DAY AS LATER
UPDATES MAY BE NECESSARY ALONG WITH POSSIBLE ADVISORIES. HOOLEY
&&
.SHORT TERM...VALID FOR TDY AND SAT...
NORTHWEST FLOW ALOFT WILL CONTINUE THROUGH SATURDAY...WITH A
SERIES OF SHORTWAVES MOVING SOUTHEASTWARD THROUGH THE REGION.
SATELLITE SHOWS ONE SHORTWAVE THAT IS GENERATING SOME SNOW
SHOWERS...MOVING THROUGH EASTERN MONTANA...WHILE A MORE POTENT
SHORTWAVE IS ABOUT TO ENTER NORTHWEST MONTANA. AS THAT SHORTWAVE
MOVES THROUGH THE CWA TODAY INTO TONIGHT...IT WILL WORK WITH
STRONG LOW TO MID LEVEL INSTABILITY AND ATTENDANT PACIFIC MOISTURE
TO GENERATE MORE SNOW SHOWERS. THE SYSTEM IS NOT TREMENDOUSLY
ORGANIZED...SO A WIDESPREAD SNOW EVENT DOES NOT APPEAR LIKELY.
WITH THE INSTABILITY AND OROGRAPHIC ENHANCEMENT...THOUGH...WE WILL
SEE SOME PRECIP BANDS FORM...SO IT WOULD NOT SURPRISE ME TO SEE
SOME LOCALIZED REPORTS OF A COUPLE OF INCHES OF SNOW WHERE THESE
BANDS DO SET UP...PARTICULARLY OVER AND DOWNSTREAM OF THE
CRAZIES...LITTLE BELTS...BIG SNOWIES AND BEARTOOTH MOUNTAINS. SOME
UPSLOPE FLOW MAY ALSO ENHANCE THE SNOWFALL POTENTIAL IN THE
BEARTOOTH FOOTHILLS NEAR RED LODGE AND NYE. HIGH TEMPERATURES
TODAY ARE EXPECTED TO REACH THE UPPER 20S TO UPPER 30S. THE LOWER
ATMOSPHERE SHOULD BE WELL MIXED TODAY...ESPECIALLY NEAR SHOWER
ACTIVITY...SO IT WILL BE FAIRLY WINDY.
A MODIFIED ARCTIC AIRMASS WILL MOVE INTO THE REGION TONIGHT INTO
SATURDAY BEHIND THE SHORTWAVE. THIS WILL INCREASE FRONTOGENESIS
AND UPSLOPE FLOW ACROSS THE WESTERN HALF OF THE REGION AT THE SAME
TIME MORE SHORTWAVE ENERGY AND JET ENERGY INFLUENCE THE REGION.
IT WILL NOT BE QUITE AS UNSTABLE IN THE LOW TO MID LEVELS...BUT
THE AFOREMENTIONED FORCING MECHANISMS WILL WORK WITH OROGRAPHIC
ENHANCEMENT IN NW FLOW ALOFT TO CONTINUE TO PRODUCE SNOW IN THE
HIGHER TERRAIN AS WELL AS SOME SNOWBANDS. AGAIN...SOME
ACCUMULATING SNOW IS LIKELY ACROSS THE WESTERN HALF OF THE
REGION...WITH LOCAL ENHANCEMENT IN THE MOUNTAINS AND WITHIN ANY
BAND THAT SETS UP. TEMPERATURES WILL BE QUITE A BIT COLDER
SATURDAY AS HIGHS ARE ONLY EXPECTED TO REACH THE TEENS TO LOW 20S.
STC
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
GREAT AGREEMENT ON ALL MODELS FOR AN UNSEASONABLY COLD STRETCH OF
WEATHER WITH A GREAT CHANCE AT A PROLONGED PERIOD OF ACCUMULATING
SNOW SUNDAY THROUGH MONDAY. STRONG SHORTWAVE TROUGH DROPS OUT OF
CANADA AND SLIDES INTO THE NORTHERN PLAINS SUNDAY WHILE A FLAT
UPPER RIDGE MOVES TOWARD THE GREAT BASIN. THIS PROCESS WILL ALLOW
COLD AIR TO DROP INTO THE FORECAST AREA WITH -20C ADVERTISED AT
850MB. THE FLAT RIDGE TO THE WEST WILL ALLOW PACIFIC MOISTURE TO
STREAM OVER THE COLD AIR AND PRODUCE OVER RUNNING SNOWFALL.
THE 285K SURFACE ADVERTISES THE STRONGEST INSENTROPIC ASCENT ON
SUNDAY NIGHT INTO EARLY MONDAY FOR MOST OF THE AREA. THE
ISENTROPIC LIFT WILL GET GOING SATURDAY NIGHT OVER THE WEST AND
THEN KICK INTO SOUTH CENTRAL MONTANA SUNDAY MORNING AND THEN CRANK
UP LATE SUNDAY AFTERNOON AND SUNDAY NIGHT. HAVE RAISED POPS MOST
LOCATIONS AND STARTED SNOW A LITTLE EARLIER. SNOW WILL CONTINUE
THROUGH THE DAY MONDAY AND VERY SLOWLY TAPER OFF OVER WESTERN AND
CENTRAL ZONES MONDAY NIGHT. RAISED POPS MONDAY NIGHT AS MODEL RUNS
CONTINUE TO DELAY DRYING FROM THE NORTH. WILL EASILY SEE 4 TO 8
INCHES OF SNOW OVER THE TWO DAY PERIOD. TEMPERATURES WILL BE COLD
FOR THIS TIME OF YEAR WITH HIGHS IN THE SINGLE DIGITS TO LOWER
TEENS SUNDAY AND MONDAY. THE COLDEST NIGHT WILL LIKELY BE MONDAY
NIGHT WITH READINGS FALLING BELOW ZERO.
A REINFORCING SHOT OF COLD AIR WILL PLOW THROUGH THE AREA ON
TUESDAY BUT WILL BE LIMITED WITH MOISTURE. THIS WILL SERVE TO KEEP
THINGS UNSEASONABLY COLD AROUND HERE. SUBTLE WARMING SHOULD TAKE
PLACE WEDNESDAY AND THURSDAY IN LOW LEVEL DOWNSLOPE. MODELS WERE
POINTING TO ANOTHER SHOT OF COLD AIR TO PUSH IN FRIDAY AND
SATURDAY. TWH
&&
.AVIATION...
SCATTERED SNOW SHOWERS CAN BE EXPECTED TODAY...ALONG WITH 20-35KT
NORTHWEST WIND GUSTS. THE HEAVIER SNOW SHOWERS WILL DROP
CONDITIONS TO IFR LOCALLY. MOUNTAINS WILL BE FREQUENTLY OBSCURED.
VFR WILL PREVAIL OUTSIDE OF THE SHOWER ACTIVITY. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 037 014/022 006/015 001/010 902/017 009/023 008/022
6/J 55/S 48/S 97/S 41/B 00/U 12/S
LVM 032 007/020 901/016 002/016 000/023 012/032 011/026
6/J 64/S 48/S 97/S 52/S 01/B 13/S
HDN 037 015/024 009/018 003/011 904/018 004/025 004/023
6/J 54/S 38/S 97/S 31/B 00/U 12/S
MLS 034 011/020 001/013 901/006 000/013 001/018 904/013
4/J 32/S 13/S 74/S 10/U 00/U 12/S
4BQ 035 014/023 008/018 003/010 902/017 002/023 002/020
4/J 33/S 14/S 87/S 31/B 00/U 12/S
BHK 029 006/017 001/010 907/003 905/011 904/017 910/012
6/J 32/S 12/S 63/S 10/U 00/U 01/B
SHR 034 013/019 003/020 004/014 902/020 005/028 005/024
5/J 45/S 46/S 87/S 51/B 01/U 12/S
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
300 PM CST FRI FEB 21 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 159 PM CST FRI FEB 21 2014
A BROAD CYCLONIC CIRCULATION IS INDICATED BY 12Z MODEL RUNS TO
REMAIN IN PLACE ACROSS MUCH OF THE NORTHERN HALF OF THE NATION
DURING THE PERIOD. THIS WILL RESULT IN TEMPERATURES TRENDING
COLDER THROUGH THE PERIOD WITH A CHANCE OF SNOW COMING INTO THE
AREA SUNDAY NIGHT INTO MONDAY.
A RATHER SHARP THERMAL GRADIENT WAS IN PLACE ACROSS THE REGION
AT 20Z WITH THE BOUNDARY STRETCHING FROM CENTRAL SOUTH DAKOTA
THROUGH NORTHEAST IOWA AND NORTHERN ILLINOIS. A WEAK SURFACE WAVE
IS FORECAST TO TRACK SOUTHEAST ALONG THIS GRADIENT TONIGHT AND
BE OVER CENTRAL ILLINOIS BY SATURDAY MORNING. SHORT RANGE MODELS
INDICATE SOME POTENTIAL FOR LIGHT SNOW NORTH OF THE WAVE LATE
TONIGHT. QPF LOOKS A BIT OVERDONE BY THE RAP COMPARED TO THE LONG
RANGE MODELS BUT HAVE INCLUDED A MENTION OF SCATTERED FLURRIES
FOR NORTHEAST NEBRASKA INTO SOUTHWEST IOWA AS THIS FEATURE MOVES
THROUGH TONIGHT.
THE COLD FRONT ASSOCIATED WITH THE WEAK LOW SINKS SOUTH INTO THE
SOUTHERN PLAINS AND LOWER OHIO VALLEY ON SATURDAY WITH COLD AIR
SLOWLY MOVING SOUTH BEHIND THE FRONT. SOME LIGHT SNOW BREAKS OUT
OVER THE WESTERN HIGH PLAINS SATURDAY AFTERNOON AS UPSLOPE FLOW
DEVELOPS AND CONTINUES SATURDAY NIGHT WITH SOME SPREAD TO THE EAST
INTO SOUTH CENTRAL NEBRASKA ASSOCIATED WITH WEAK ISENTROPIC
FORCING. HAVE BACKED OFF A BIT ON POPS FOR SOUTHWEST PORTION OF
THE FA FOR LATE SATURDAY NIGHT WITH SOME SLIGHT POPS INTO SUNDAY
MORNING AS BETTER FORCING IS EXPECTED TO REMAIN FURTHER WEST.
WEAK CYCLOGENESIS OCCURS OVER SOUTHEAST WYOMING ON SUNDAY AS AN
UPPER WAVE BEGINS TO DROP INTO THE NORTHERN ROCKIES. SOUTHERLY LOW
LEVEL FLOW DEVELOPS OVER THE CENTRAL PLAINS SUNDAY NIGHT IN
RESPONSE TO THIS DEVELOPMENT WITH A STRONG BAROCLINIC ZONE OVER
NORTHERN NEBRASKA BY MONDAY MORNING. A WIDESPREAD AREA OF SNOW
IS LIKELY ALONG AND NORTH OF THIS BOUNDARY SUNDAY NIGHT INTO
MONDAY MORNING. SNOW THEN SPREADS EAST ON MONDAY INTO NORTHERN
IOWA AS THE UPPER WAVE TRACKS TOWARD THE UPPER MIDWEST WITH THE
BETTER CHANCE OF SNOW EXPECTED NORTH OF INTERSTATE 80. MUCH COLDER
AIR WILL ALSO SURGE INTO THE FA BEHIND THIS WAVE ON MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 159 PM CST FRI FEB 21 2014
A COLD WINTER PATTERN WILL CONTINUE THROUGH THE PERIOD. ONE WEAK
WAVE WILL CONTINUE TO DRIFT SOUTHWARD AT THE BEGINNING OF THE
PERIOD...AND WITH H85 TEMPS WELL WITHIN THE DENDRITIC LAYER...COULD
SEE LINGERING FLURRIES MONDAY NIGHT...BUT LITTLE OR NO ACCUMULATION.
OTHERWISE...NORTHERLY FLOW WILL PERSIST TUESDAY AHEAD OF THE FIRST
SURGE OF EVEN COLDER AIR THAT ARRIVES TUESDAY NIGHT AND LINGERS
THROUGH WEDNESDAY...ALTHOUGH WESTERLY FLOW REDEVELOPS WEDNESDAY
WHICH SHOULD KEEP TEMPS IN THE 20S INSTEAD OF THE TEENS. A SECONDARY
SURGE OF COLDER TEMPS ARRIVES BY DAYBREAK THURSDAY AS SURFACE FLOW
AGAIN RETURNS TO THE NORTH/NORTHEAST. THIS SHOULD KEEP TEMPS IN THE
TEENS ON THURSDAY...BUT VERY LITTLE MOISTURE AVAILABLE SO NO CHANCE
OF PRECIP. A WEAK RETURN FLOW TRIES TO DEVELOP ON FRIDAY...BUT TEMPS
SHOULD REMAIN WELL BELOW NORMAL.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1230 PM CST FRI FEB 21 2014
VFR CONDITIONS THROUGH THE PERIOD. THERE WILL BE AN INCREASE IN
MID CLOUDS THIS AFTERNOON WITH SOME BKN CIGS FL050-060 AND
FL100-120 AND COULD BE SOME FLURRIES OR SPRINKLES. DUE TO ISOLATED
NATURE OF PRECIPITATION WILL NOT MENTION IN TAFS.SURFACE WINDS
WILL BECOME NORTHWEST AND VARY FROM 10 TO 18KTS SUSTAINED WITH
SOME HIGHER GUSTS. AFTER 00Z...THE WINDS WILL SETTLE DOWN TO LESS
THAN 10KTS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...DEWALD
AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 PM EST FRI FEB 21 2014
.SYNOPSIS...A STRONG COLD FRONT WILL PUSH SOUTH AND EAST OF THE AREA THIS EVENING.
HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST TONIGHT AND SATURDAY...THEN DRIFT
EAST AND OFFSHORE ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...
QLCS CURRENTLY EXITING THE CWA AND WILL PLAN TO CANCEL TORNADO WATCH
23 FOR OUR COUNTIES WITH THE AFTERNOON PACKAGE. THE SYNOPTIC COLD
FRONT WILL MAKING ITS WAY THROUGH THE WESTERN PIEDMONT RIGHT NOW AND
WILL PUSH EAST THROUGH THE CWA BY AROUND 00Z. RH CROSS-SECTIONS
SUGGEST THERE MAY BE JUST ENOUGH SHALLOW MOISTURE CONVERGENCE ALONE
THE FRONT FOR A FEW ISOLATED SHOWERS. RECENT HRRR RUNS HAVEN`T BEEN
EXTREMELY CONSISTENT WITH THE COVERAGE OF ANY ADDITIONAL
SHOWERS...BUT WE WILL MAINTAIN JUST A SLIGHT CHANCE POP UNTIL HE
FRONT CLEARS THE AREA. OTHERWISE...MUCH DRIER AIR WILL FILTER INTO
THE AREA BEHIND THE FRONT ...WITH DEWPOINTS DROPPING INTO THE 20S.
HIGH PRESSURE RIDGING IN FROM THE WEST WILL ALLOW WESTERN AREAS TO
RADIATE THE BEST UNDER CLEAR SKIES...WITH LOWS DIPPING INTO THE MID
30S TO NEAR 40.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...
WELL SOUTH OF THE DEEP POLAR VORTEX OVER SOUTHEAST CANADA... THE
CAROLINAS WILL LIE UNDER THE INFLUENCE OF BROAD WESTERLY CYCLONIC
FLOW ALOFT. AT THE SURFACE...HIGH PRESSURE OF PACIFIC ORIGINS WILL
BRIEFLY BUILD OVER THE SOUTHEAST US ON SATURDAY... SHIFTING OFFSHORE
SATURDAY NIGHT WITH SOUTHERLY RETURN FLOW SUNDAY BEFORE A DRY
SURFACE COLD FRONT MOVES SOUTHEASTWARD THROUGH THE AREA SUNDAY
EVENING.
THIS WILL TRANSLATE INTO TO DRY CONDITIONS WITH CONTINUED SPRING-
LIKE TEMPERATURES INTO THE 60S ON SATURDAY...WITH SOME UPPER 60S TO
LOWER 70S ON SUNDAY. LOWS SATURDAY NIGHT IN THE 40S...COOLING OFF
INTO THE 30S BEHIND THE FRONT SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...
DRY CONDITIONS WILL CONTINUE INTO MONDAY...ALBEIT WITH COOLER-MORE
SEASONABLE TEMPERATURES AS A PROGRESSIVE NORTHERN STREAM HIGH OVER
THE CENTRAL US BUILDS EASTWARD INTO THE AREA.
TUESDAY THROUGH WEDNESDAY...AN EVEN STRONGER POLAR VORTEX DROPPING
SOUTHEASTWARD INTO SOUTHERN CANADA WILL RESULT IN A SIGNIFICANT
PATTERN CHANGE WITH A DEEP UPPER TROUGH FORECAST TO DEVELOP EAST OF
THE ROCKIES. WHILE THE OVERALL PATTERN IS HIGHLY AGREED UPON...THERE
IS STILL A FAIR AMOUNT OF UNCERTAINTY THATS LARGELY OWED TO THE
TIMING OF THE MID-LEVEL ENERGY EJECTING EASTWARD FROM THE CENTRAL
ROCKIES...AND TO A LESSER EXTENT...WEAK S/W IMPULSES OUT AHEAD OF
THE LEAD TROUGH THAT WILL EVENTUALLY RESULT IN SURFACE CYCLOGENESIS
ALONG A BAROCLINIC FRONTAL ZONE EXTENDING FROM THE GULF OF MEXICO TO
THE SE COAST. INCREASING RAIN CHANCES TUESDAY THROUGH
WEDNESDAY...WITH POPS/QPF DEPENDING ON TRACK/LOCATION OF COASTAL LOW
AND ALL LIQUID AT THIS TIME AS SIGNIFICANTLY COLDER AIR ARRIVES
THURSDAY THROUGH FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...
LINE OF CONVECTION MOVING THROUGH CENTRAL NC CURRENTLY EXTENDS FROM
KIXA TO EAST OF KRDU TO KFAY. WITHIN THE LINE..CEILINGS ARE
LIFR/IFR...WITH HEAVY RAIN AND LIFR VSBYS ARE TIMES. WINDS JUST
AHEAD WITHIN STRONGER STORMS WILL GUST TO 30-40KT..MOSTLY FROM THE
WEST-SOUTHWEST. THE LINE IS EXPECTED TO MOVE EAST OF I-95 WITHIN
THE NEXT HOUR OR TWO AND BE CLEAR OF THE AREA BY 21Z. WEST OF THE
LINE...SOME LIGHT RAIN IS STILL FALLING AND CEILINGS ARE MOSTLY MVFR
OR VFR. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM HAS MOVED
THROUGH KGSO AND KINT...WHERE WINDS FROM THE NORTHWEST GUSTED TO
30KT. THIS WILL BE POSSIBLE AT KRDU...KFAY AND KINT BY 20-22Z AS
THE FRONT PUSHES EAST. SKIES WILL THEN CLEAR BEHIND THE FRONT AND
VFR CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE TAF PERIOD.
OUTLOOK... A DRY COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY
NIGHT...WITH ONLY A SMALL CHANCE OF SUB-VFR CONDITIONS. OTHERWISE...
VFR CONDITIONS ARE EXPECTED THROUGH EARLY TUESDAY WHEN ANOTHER
WEATHER SYSTEM IS EXPECTED TO IMPACT THE REGION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM..CBL
LONG TERM...CBL
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
303 PM EST FRI FEB 21 2014
.SYNOPSIS...A STRONG COLD FRONT WILL PUSH SOUTH AND EAST OF THE AREA THIS EVENING.
HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST TONIGHT AND SATURDAY...THEN DRIFT
EAST AND OFFSHORE ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...
QLCS CURRENTLY EXITING THE CWA AND WILL PLAN TO CANCEL TORNADO WATCH
23 FOR OUR COUNTIES WITH THE AFTERNOON PACKAGE. THE SYNOPTIC COLD
FRONT WILL MAKING ITS WAY THROUGH THE WESTERN PIEDMONT RIGHT NOW AND
WILL PUSH EAST THROUGH THE CWA BY AROUND 00Z. RH CROSS-SECTIONS
SUGGEST THERE MAY BE JUST ENOUGH SHALLOW MOISTURE CONVERGENCE ALONE
THE FRONT FOR A FEW ISOLATED SHOWERS. RECENT HRRR RUNS HAVEN`T BEEN
EXTREMELY CONSISTENT WITH THE COVERAGE OF ANY ADDITIONAL
SHOWERS...BUT WE WILL MAINTAIN JUST A SLIGHT CHANCE POP UNTIL HE
FRONT CLEARS THE AREA. OTHERWISE...MUCH DRIER AIR WILL FILTER INTO
THE AREA BEHIND THE FRONT ...WITH DEWPOINTS DROPPING INTO THE 20S.
HIGH PRESSURE RIDGING IN FROM THE WEST WILL ALLOW WESTERN AREAS TO
RADIATE THE BEST UNDER CLEAR SKIES...WITH LOWS DIPPING INTO THE MID
30S TO NEAR 40.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 304 AM FRIDAY...
HIGH PRESSURE WILL BUILD ACROSS THE AREA IN THE WAKE OF THE FRONT...
AND A MUCH DRIER AIRMASS WILL BE IN PLACE ACROSS THE AREA BRINGING
MOSTLY SUNNY SKIES. INITIAL COLD ADVECTION EARLY SATURDAY WILL
BECOME NEUTRAL... AS UPPER LEVEL FLOW REMAINS PRIMARILY
SOUTHWESTERLY DURING THE DAY SATURDAY... AND TEMPERATURES WILL
REMAIN A FEW DEGREES ABOVE NORMAL.
HIGH PRESSURE WILL MOVE OFFSHORE SUNDAY... WARMER SOUTHERLY FLOW...
AND INCREASING LOW LEVEL THICKNESSES WILL RESULT IN TEMPERATURES
SLIGHTLY WARMER THAN SATURDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 305 AM FRIDAY...
A DRY COLD FRONT WILL MOVE THROUGH THE AREA MONDAY MORNING...
BRINGING TEMPERATURES MUCH CLOSER TO NORMAL FOR THE BEGINNING OF THE
WEEK.
STRONG SIGNAL FOR RIDGING ACROSS THE WESTERN US... WITH BROAD
TROUGHING DEVELOPING OVER THE EAST COAST THROUGH THE WEEK. THIS WILL
BRING TEMPS BACK BELOW NORMAL. WAVES MOVING THROUGH THE NORTHWEST
FLOW GENERALLY STAY NORTH OF OUR AREA THROUGH THIS PERIOD... WITH
THE EXCEPTION OF WEDNESDAY WHEN A AN IMPULSE AND ASSOCIATED COLD
FRONT ARE PROGGED TO MOVE THROUGH THE AREA... AND THE POTENTIAL FOR
A LOW PRESSURE SYSTEM TO DEVELOP OFF THE CAROLINA COAST... BRINGING
THE BEST CHANCE FOR PRECIPITATION DURING THIS PERIOD.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...
LINE OF CONVECTION MOVING THROUGH CENTRAL NC CURRENTLY EXTENDS FROM
KIXA TO EAST OF KRDU TO KFAY. WITHIN THE LINE..CEILINGS ARE
LIFR/IFR...WITH HEAVY RAIN AND LIFR VSBYS ARE TIMES. WINDS JUST
AHEAD WITHIN STRONGER STORMS WILL GUST TO 30-40KT..MOSTLY FROM THE
WEST-SOUTHWEST. THE LINE IS EXPECTED TO MOVE EAST OF I-95 WITHIN
THE NEXT HOUR OR TWO AND BE CLEAR OF THE AREA BY 21Z. WEST OF THE
LINE...SOME LIGHT RAIN IS STILL FALLING AND CEILINGS ARE MOSTLY MVFR
OR VFR. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM HAS MOVED
THROUGH KGSO AND KINT...WHERE WINDS FROM THE NORTHWEST GUSTED TO
30KT. THIS WILL BE POSSIBLE AT KRDU...KFAY AND KINT BY 20-22Z AS
THE FRONT PUSHES EAST. SKIES WILL THEN CLEAR BEHIND THE FRONT AND
VFR CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE TAF PERIOD.
OUTLOOK... A DRY COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY
NIGHT...WITH ONLY A SMALL CHANCE OF SUB-VFR CONDITIONS. OTHERWISE...
VFR CONDITIONS ARE EXPECTED THROUGH EARLY TUESDAY WHEN ANOTHER
WEATHER SYSTEM IS EXPECTED TO IMPACT THE REGION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM..SEC
LONG TERM...SEC
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1100 AM CST FRI FEB 21 2014
.AVIATION...
GUSTY SOUTH WINDS WILL CONTINUE THIS AFTERNOON BEFORE DYING DOWN
AFTER SUNSET. OTHERWISE...VFR CONDITIONS EXPECTED THROUGH THE TAF
PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1033 AM CST FRI FEB 21 2014/
DISCUSSION...
WINDS AND TEMPERATURES ARE INCREASING RAPIDLY THIS MORNING AS THE
SHALLOW SURFACE INVERSION MIXES OUT. IT APPEARS THAT WE WILL START
SEEING RED FLAG WARNING CRITERIA BEING MET AROUND NOON...AS
PLANNED.
ALL FEATURES OF THE FORECAST APPEAR TO BE IN GOOD SHAPE
AT THIS TIME...AND NO CHANGES ARE PLANNED FOR THIS MORNING.
PREV DISCUSSION... /ISSUED 527 AM CST FRI FEB 21 2014/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH TO SOUTHWEST WINDS WILL INCREASE AND BECOME GUSTY
AT ALL SITES BY 17Z. THESE WINDS WILL SUBSIDE AROUND 00Z.
MBS
PREV DISCUSSION... /ISSUED 404 AM CST FRI FEB 21 2014/
DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 39 66 42 52 / 0 0 0 10
HOBART OK 38 70 41 52 / 0 0 0 0
WICHITA FALLS TX 43 76 47 61 / 0 0 0 0
GAGE OK 21 63 34 46 / 0 0 0 0
PONCA CITY OK 35 60 36 47 / 0 0 10 10
DURANT OK 44 70 52 61 / 0 0 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ005>030-
033>040-044-045.
TX...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
23/84/14
AREA FORECAST DISCUSSION
NWS NORMAN OK
1033 AM CST FRI FEB 21 2014
.DISCUSSION...
WINDS AND TEMPERATURES ARE INCREASING RAPIDLY THIS MORNING AS THE
SHALLOW SURFACE INVERSION MIXES OUT. IT APPEARS THAT WE WILL START
SEEING RED FLAG WARNING CRITERIA BEING MET AROUND NOON...AS
PLANNED.
ALL FEATURES OF THE FORECAST APPEAR TO BE IN GOOD SHAPE
AT THIS TIME...AND NO CHANGES ARE PLANNED FOR THIS MORNING.
&&
.PREV DISCUSSION... /ISSUED 527 AM CST FRI FEB 21 2014/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH TO SOUTHWEST WINDS WILL INCREASE AND BECOME GUSTY
AT ALL SITES BY 17Z. THESE WINDS WILL SUBSIDE AROUND 00Z.
MBS
PREV DISCUSSION... /ISSUED 404 AM CST FRI FEB 21 2014/
DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 39 66 42 / 0 0 0 0
HOBART OK 68 38 70 41 / 0 0 0 0
WICHITA FALLS TX 71 43 76 47 / 0 0 0 0
GAGE OK 64 21 63 34 / 0 0 0 0
PONCA CITY OK 63 35 60 36 / 0 0 0 10
DURANT OK 65 44 70 52 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ005>030-
033>040-044-045.
TX...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
23/84
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
244 PM CST FRI FEB 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 244 PM CST FRI FEB 21 2014
MAIN FORECASTS CONCERNS ARE ON SNOW CHANCES MONDAY NIGHT. FOCUS
THEN TURNS TO BITTERLY COLD TEMPERATURES LATE NEXT WEEK.
LATEST SURFACE OBSERVATIONS AND REPORTS ACROSS THE AREA INDICATED
AREAS OF BLOWING AND DRIFTING SNOW...LEADING TO HAZARDOUS TRAVEL
CONDITIONS. THE WORST OF THE BLOWING AND DRIFTING SNOW WAS
OCCURRING WEST OF THE MISSISSIPPI RIVER. CONDITIONS ARE EXPECTED
TO IMPROVE LATE THIS AFTERNOON INTO EARLY THIS EVENING. THE
POTENT LOW PRESSURE SYSTEM RESPONSIBLE FOR THE STRONG
WEST/NORTHWEST WINDS WAS CENTERED OVER NORTH CENTRAL LAKE
SUPERIOR. THE LOW WILL LIFT NORTHEAST OF THE REGION TONIGHT AS
HIGH PRESSURE EDGES IN FROM THE NORTHERN PLAINS.
A PERSISTENT PRESSURE GRADIENT WILL REMAIN IN PLACE OVER THE UPPER
MISSISSIPPI RIVER VALLEY TONIGHT THROUGH SATURDAY CREATING WEST
WINDS OF 10 TO 17 MPH. THESE WINDS WILL MAKE IT FEEL CHILLY ON
SATURDAY WITH WIND CHILLS IN THE SINGLE DIGITS TO SINGLE DIGITS
BELOW ZERO. PLAN ON HIGH TEMPERATURES RANGING FROM THE MID TEENS TO
LOWER 20S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 244 PM CST FRI FEB 21 2014
A CHILLY NIGHT IN STORE FOR THE AREA SATURDAY NIGHT WITH LOWS
RANGING ROM THE SINGLE DIGITS BELOW ZERO OVER SOUTHEAST MINNESOTA
THROUGH NORTH CENTRAL WISCONSIN TO THE SINGLE DIGITS ABOVE ZERO OVER
FAR SOUTHWEST WISCONSIN INTO NORTHEAST IOWA. WIND CHILL VALUES ARE
EXPECTED TO DIP INTO THE 20 TO 27 BELOW RANGE LATE SATURDAY NIGHT
INTO EARLY SUNDAY MORNING OVER NORTH CENTRAL WISCONSIN.
ELSEWHERE...PLAN ON WIND CHILLS FALLING INTO THE TEENS BELOW ZERO.
DRY...QUIET...AND CHILLY CONDITIONS WILL CONTINUE THROUGH SUNDAY
WITH HIGHS MAINLY IN THE TEENS AND LOWS IN THE SINGLE DIGITS BELOW
ZERO.
A SHORTWAVE TROUGH IS EXPECTED TO DROP INTO THE REGION FROM THE
NORTHERN PLAINS LATE MONDAY AFTERNOON INTO MONDAY NIGHT PRODUCING
LIGHT SNOW ACROSS AREA. AT THIS TIME...THE HIGHEST CHANCES FOR SNOW
LOOK TO BE SOUTH AND WEST OF THE INTERSTATE 94 CORRIDOR. LATEST
THINKING IS THAT SNOW ACCUMULATIONS SHOULD RANGE FROM 1 TO 3
INCHES...WITH THE HIGHER ACCUMULATIONS OCCURRING OVER NORTHEAST IOWA
INTO FAR SOUTHWEST WISCONSIN...BUT THIS DEPENDS ON THE EXACT STORM
TRACK. GIVEN THE CONSISTENT SIGNAL FOR SNOW OVER THESE AREAS HAVE
DECIDED TO INCREASE PRECIPITATION CHANCES.
A BITTERLY COLD ARCTIC AIRMASS MOVES BACK INTO THE REGION LATE
TUESDAY INTO WEDNESDAY WITH 850 MB TEMPERATURES PLUMMETING INTO THE
-22 TO -25 C RANGE. WIND CHILL VALUES OF 20 TO 25 BELOW ZERO LOOK
LIKELY TUESDAY NIGHT INTO WEDNESDAY MORNING AND A WIND CHILL
ADVISORY WILL LIKELY BE NEEDED. THE COLDEST TEMPERATURES ARE
EXPECTED TO SETTLE IN WEDNESDAY INTO THURSDAY WHEN LOWS LOOK TO FALL
INTO THE TEENS TO AROUND 20 BELOW ZERO. WIND CHILL HEADLINES APPEAR
LIKELY WEDNESDAY NIGHT AND AGAIN THURSDAY NIGHT...WHEN WIND CHILL
VALUES OF 20 TO 30 BELOW ZERO ARE EXPECTED. THURSDAY NIGHT LOOKS TO
HAVE THE COLDEST AIR TEMPERATURES WHEN LOWS WILL FALL INTO THE TEENS
TO AROUND 20 BELOW ZERO. 850 MB TEMPERATURE STANDARDIZED ANOMALIES
OF -2.0 TO -2.5 MOVE INTO THE REGION LATE THURSDAY NIGHT INTO
FRIDAY PUTTING US IN NEAR RECORD TERRITORY FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1150 AM CST FRI FEB 21 2014
STRONG WEST WINDS AT 20 TO 30 WITH GUSTS TO 35 WILL PERSIST THROUGH
MUCH OF THE AFTERNOON HOURS...PER LATEST RAP SOUNDINGS. KRST/KLSE ON
CLEARING EDGE OF THE CLOUDS...VIA SFC OBS AND SATELLITE IMAGERY. OBS
MAY POINT TO SOME CIGS FROM BLOWING SNOW. GOING TO KEEP VSBY
RESTRICTIONS AT KRST THROUGH THE AFTERNOON. VFR CONDITIONS SHOULD BE
THE RULE TONIGHT INTO SATURDAY WITH SKC SKIES AND WINDS TAPERING
OFF INTO THE 10 TO 15 KT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ017-
029-032>034-041>044-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 AM CST FRI FEB 21 2014
.UPDATED...
1150 AM CST FRI FEB 21 2014
MANY ROAD CLOSURES CONTINUE ACROSS SOUTHEAST MN AND NORTHEAST
IA...WITH A TOW BAN IN EFFECT FOR SOME LOCATIONS. WINDS ARE GOING TO
STAY STRONG AND GUSTY THROUGH THE AFTERNOON...WITH ANY SUNSHINE ONLY
HELPING MIX DOWN THE STRONG NEAR SFC WINDS. WILL LET THE WARNINGS
EXPIRE...BUT REPLACE WITH A WINTER WEATHER ADV FOR BLOWING/DRIFTING
SNOW FOR THE ENTIRE FORECAST AREA THROUGH 00Z. CONDITIONS STILL
WARRANT IT.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CST FRI FEB 21 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM ALASKA DOWN INTO THE MID-MISSISSIPPI
RIVER VALLEY AND A DEEP UPPER LOW OVER NORTHERN WI. UNDERNEATH THE
UPPER LOW WAS A 978 MB SURFACE LOW NEAR RHINELANDER. A VERY TIGHT
PRESSURE GRADIENT SOUTHWEST OF THE LOW WAS SUPPORTING SURFACE WINDS
OF 25 TO 35 MPH WITH GUSTS UP TO 55 MPH. THE COLD CONVEYOR BELT
WRAPPING AROUND THE NEARLY VERTICALLY STACKED LOW WAS STILL BRINGING
SNOW TO THE FORECAST AREA...HEAVIEST OVER NORTH CENTRAL WI. EARLIER
LAST EVENING THE STRONG WINDS WERE NOT REDUCING VISIBILITIES THAT
MUCH IN SOUTHEAST MN/NORTHEAST IA PER ASOS/AWOS OBSERVATIONS...DUE
TO THE WET NATURE OF THE SNOW. HOWEVER...CALLS TO COUNTY SHERIFFS
IN THE SAME AREA WERE REPORTING WHITEOUTS WITH SOME ROADS
CLOSED...SUGGESTING ASOS/AWOS OBSERVATIONS WERE NOT FULLY
REPRESENTATIVE. IN ADDITION...POWER OUTAGES WERE A MAJOR ISSUE
WITH THE WEIGHT OF THE WET SNOW ON TREES/POWER LINES AND WINDS.
NOW THE WINDS HAVE ADVECTED COLDER AIR INTO THE FORECAST AREA AS
NOTED BY TEMPERATURES IN THE TEENS TO LOW 20S. THE COLDER AIR HAS
ALLOWED THE SNOW TO BECOME DRIER...MORE ABLE TO BLOW.
THE NEARLY VERTICALLY STACKED LOW WILL CONTINUE LIFTING
NORTHEASTWARD OVER THE NEXT 24 HOURS...REACHING NORTHERN ONTARIO
THIS EVENING. AS THE LOW PULLS AWAY...THE WINDS WILL GRADUALLY
RELAX...DROPPING FROM 20 TO 35 MPH WITH HIGHER GUSTS DURING THE
MORNING TO 10 TO 25 MPH BY 00Z. FURTHER DIMINISHING OF THE WINDS ARE
EXPECTED TONIGHT. IN TERMS OF THE COLD CONVEYOR BELT OF SNOW...GOOD
AGREEMENT EXISTS THAT THE SNOW SHOULD EXIT MOST LOCATIONS WEST OF
THE MISSISSIPPI RIVER BY 12Z...LOCATIONS SOUTHWEST OF I-94 BY
18Z...AND THE CHIMNEY AREA BY 00Z. MUCH OF THE SNOW SHOULD BE
LIGHT WITH THE SYSTEM OCCLUDED AND MOVING AWAY. JUXTAPOSITION OF
THE WINDS AND SNOW SUGGESTS CONTINUATION OF HAZARDS OVER THE
NORTHWEST HALF OF THE FORECAST AREA. CONTEMPLATED RIGHT NOW
CANCELING SOME OF THE WINTER WEATHER ADVISORY...BUT HAVE KEPT IT
GOING FOR NOW DUE TO LIGHT SNOW GOING THROUGH AND STRONG WINDS
ALLOWING THAT TO BLOW AROUND...WINDS AT ADVISORY LEVEL...AND COLD
AIR ALLOWING RECENT WATER TO FREEZE.
WE SHOULD ALSO SEE SOME CLEARING TODAY SOUTHWEST TO NORTHEAST AS
DRIER/SUBSIDENT AIR OVER THE PLAINS ADVECTS IN BEHIND THE SYSTEM.
THIS CLEARING IS WELL EVIDENT OVER WESTERN IOWA AND FAR SOUTHWEST MN
CURRENTLY. THE DRIER AIR HOLDS INTO TONIGHT...SO ALTHOUGH SOME
SHORTWAVES ROTATING AROUND THE UPPER LOW ARE PROGGED TO COME ACROSS
THE FORECAST AREA...NO PRECIPITATION OR EVEN CLOUD IMPACTS ARE
EXPECTED FROM THEM.
925MB TEMPERATURES OF -8 TO -12C TODAY WILL RESULT IN MUCH COOLER
HIGHS TODAY COMPARED TO YESTERDAY...AS MUCH AS 15 TO 20 DEGREES
COLDER. 925MB TEMPS COOL EVEN MORE TONIGHT...TO -10 TO -16C BY 12Z
SATURDAY...COLDEST NORTH. HAVING MOSTLY CLEAR SKIES...COOLING TEMPS
AND FRESH SNOW IS CONCERNING FOR TEMPERATURES TO TANK...BUT MIXING
OF THE WINDS SHOULD HELP KEEP MOST LOCATIONS ABOVE 0F. THE LONE
EXCEPTION TO GO BELOW ZERO COULD BE UP IN TAYLOR COUNTY WHERE THE
COLDEST AIR IS FLOWING IN. COMBINATION OF THE WINDS AND FALLING
TEMPS BRINGS WIND CHILLS CLOSE BUT NOT TO -20F...WHEN WE WOULD ISSUE
WIND CHILL ADVISORIES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 214 AM CST FRI FEB 21 2014
MUCH OF THE LONG TERM PERIOD IS DOMINATED BY A STUCK UPPER LEVEL
PATTERN...RESULTING FROM AN OMEGA BLOCK THAT DEVELOPS AND
STRENGTHENS FROM ALONG THE U.S. WEST COAST INTO FAR WESTERN CANADA.
THE STRENGTHENING OMEGA BLOCK CORRELATES WELL WITH A STRATOSPHERIC
WARMING EVENT TAKING PLACE OVER THE ALEUTIANS THE NEXT FEW DAYS.
THIS OMEGA BLOCK WILL ALLOW A SERIES OF SHORTWAVE TROUGHS DROPPING
OUT OF THE ARCTIC TO COME THROUGH THE FORECAST AREA. IN THE WAKE OF
EACH TROUGH...A SURGE OF COLDER AIR WITH ARCTIC HIGH PRESSURE WILL
FOLLOW. GIVEN THE ARCTIC NATURE OF THE SHORTWAVES...MOISTURE AND
PRECIPITATION IS GOING TO BE HARD TO COME BY. THE ONLY REAL CHANCE
IT LOOKS LIKE FOR SNOW WILL COME MONDAY INTO MONDAY NIGHT WITH A
SHORTWAVE TROUGH DROPPING THROUGH THEN. STILL...AT THIS POINT...IT
DOES NOT APPEAR TO BE A BIG SNOW PRODUCER. HIGHEST CHANCES ARE
SITUATED OVER THE SOUTHWEST HALF OF THE FORECAST AREA.
NOW THE MAIN IMPACT ISSUE...THE COLD...WHICH HAS BEEN CONSISTENTLY
FORECASTED FROM THE ECMWF/GFS AND CFS. HAVING ARCTIC COLD FLOW INTO
THE FORECAST AREA ALSO CORRELATES WELL WITH THE AFOREMENTIONED
STRATOSPHERIC WARMING OVER THE ALEUTIANS.
THE WEEKEND...925MB TEMPS ARE NOT FORECAST TO CHANGE MUCH THROUGH
THE WEEKEND FROM THE -10 TO -16C PROGGED AT 12Z SATURDAY. THIS
SHOULD RESULT IN HIGHS SIMILAR FOR BOTH DAYS...RANGING FROM THE LOW
TEENS TO LOW 20S. TEMPERATURES SATURDAY NIGHT COULD FALL QUITE A BIT
WITH A WEAKER PRESSURE GRADIENT. TYPICAL COLD SPOTS WILL LIKELY
DECOUPLE...ALLOWING THEM TO APPROACH 10 BELOW. WIND CHILLS MAY FLIRT
WITH ADVISORY CRITERIA AS WELL SUNDAY MORNING.
NEXT WEEK...BEHIND THE MONDAY SHORTWAVE TROUGH...925MB TEMPS FALL TO
-18 TO -22C BY 12Z TUESDAY PER 21.00Z ECMWF/GFS. A COLDER SURGE
COMES IN TUESDAY NIGHT BEHIND ANOTHER SHORTWAVE TROUGH...WITH THOSE
925MB TEMPS DOWN TO -22 TO -26C AT 12Z WEDNESDAY. MORE IMPORTANTLY
WITH THIS COLD SURGE IS STRONGER 925MB WINDS OF 25-35 KTS...WHICH
RESULTS IN WIND CHILL ADVISORY NEED. THE FINAL AND COLDEST OF THE
COLD COMES WEDNESDAY NIGHT INTO THURSDAY. 925MB TEMPS ARE SIMILAR TO
THE TUESDAY NIGHT SURGE...BUT 850MB TEMPS APPROACH -30C IN TAYLOR
COUNTY...SUGGESTING A DEEPER COLDER AIRMASS. AND LIKE TUESDAY
NIGHT...PLENTY OF WIND IS FORECAST...SO WIND CHILL ADVISORY HAZARDS
LOOK LIKELY. IN FACT...LOWS THEMSELVES SHOULD BE IN THE SINGLE
DIGITS TO TEENS BELOW ZERO TUESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1150 AM CST FRI FEB 21 2014
STRONG WEST WINDS AT 20 TO 30 WITH GUSTS TO 35 WILL PERSIST THROUGH
MUCH OF THE AFTERNOON HOURS...PER LATEST RAP SOUNDINGS. KRST/KLSE ON
CLEARING EDGE OF THE CLOUDS...VIA SFC OBS AND SATELLITE IMAGERY. OBS
MAY POINT TO SOME CIGS FROM BLOWING SNOW. GOING TO KEEP VSBY
RESTRICTIONS AT KRST THROUGH THE AFTERNOON. VFR CONDITIONS SHOULD BE
THE RULE TONIGHT INTO SATURDAY WITH SKC SKIES AND WINDS TAPERING
OFF INTO THE 10 TO 15 KT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ017-
029-032>034.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
WIZ041>044-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094-095.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ011-
030.
&&
$$
UPDATED......RIECK
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RIECK