Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/02/14
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
945 PM PST THU JAN 30 2014
.DISCUSSION...AS OF 6:09 PM THURSDAY...WILL ISSUE AN EVENING UPDATE
FOR ONLY SOME MINOR CHANGES. LAST VISIBLE SHOTS SHOWED A WELL
DEFINED CLOUD MASS WEST OF CAPE MENDOCINO. SOME OF THE ENERGY WITH
THIS SHORTWAVE WILL PHASE WITH ENERGY OVER NORTHERN CALIFORNIA AND
SHOULD BRING ANOTHER ROUND OF POST-FRONTAL SHOWERS. ADMITTEDLY
LEANING ON THE RAP SHORT TERM MODEL FOR THIS UPDATE AS WELL AS
CURRENT SATELLITE AND RADAR TRENDS. KMUX-88D IS STARTING TO PICK
UP SOME RETURNS OUT WEST OF THE FARALLONES. THE AIRMASS IS NOW
MUCH COLDER ALOFT AND THE SHORTWAVE WILL PROVIDE MORE FAVORABLE
INSTABILITY/FORCING ALOFT. UPSHOT IS FOR THE OVERNIGHT PERIOD HAVE
INCREASED POPS...MAINLY FOR THE SOUTHERN HALF OF THE DISTRICT.
BEST CHANCES FOR SHOWERS LOOK TO BE ALONG THE SAN MATEO COAST AND
SANTA CRUZ MTNS AS WELL AS THE BIG SUR COAST. THE SYSTEM LAST
NIGHT/EARLY THIS MORNING WAS VERY MEAGER IN ITS RAIN AMOUNTS. AS
IS OFTEN THE CASE WE CAN OFTEN GET SOME OF OUR MORE SUBSTANTIAL
RAIN SHOWERS IN THE POST-FRONTAL/NW ONSHORE FLOW PATTERN FROM SAN
FRANCISCO SOUTHWARD. ANYWAY...GIVEN THE RAINFALL DEFICITS WILL
TAKE ANYTHING WE CAN SO FORECAST POPS AND QPF WERE MASSAGED FOR
SOUTHERN HALF OF CWA. CURRENT SET-UP LOOKS LIKE THE NORTH BAY WILL
MOSTLY BE MISSED. ANY SHOWER ACTIVITY SHOULD GENERALLY OCCUR
DURING THE OVERNIGHT AND BE DONE BY THE MORNING COMMUTE.
FRIDAY AND SATURDAY LOOK DRY AND SEASONABLY COOL WITH NW ONSHORE WINDS.
NEXT FORECAST FOCUS WILL BE INCOMING UPPER LOW THAT MAY SKIRT THE
COAST ROUGHLY FROM THE SANTA CRUZ MOUNTAINS SOUTHWARD THROUGH BIG
SUR. GEM AND ECMWF ARE WETTEST AND MOST BULLISH WHILE LATEST NAM
AND GFS REMAIN WEAKER WITH SYSTEM MORE OFFSHORE.
LOOKS LIKE QUIET WEATHER FOR A WHILE NEXT WEEK BUT AT LEAST THERE
IS SOME HINT OF MORE POTENTIAL STORMS IN THE EXTENDED RANGE.
&&
.PREVIOUS DISCUSSION AS OF 1:43 PM PST THURSDAY...SLIGHT CHANCE
FOR SHOWERS TONIGHT...BUT A BETTER CHANCE ON SUNDAY WITH A PASSING
LOW PRESSURE SYSTEM.
AFTER A WET START TO THE MORNING...THE SUN CAME OUT FOR MUCH OF
THE BAY AREA. THE COLD FRONT THAT BROUGHT RAIN TO THE REGION HAS
EXITED WELL TO THE SOUTH AND EAST. BEHIND THE FRONT...BREEZY CONDITIONS
EXIST ALONG THE COAST AND OVER THE COASTAL WATERS. AS FAR AS TEMPS
GO...MOST LOCATIONS ARE WITH IN A FEW DEGREES OF YESTERDAY OR A
TAD COOLER UNDER THE WEAK COLD ADVECTION.
THE BIG PICTURE SHOWS A SOMEWHAT ZONAL FLOW OVER THE REGION WITH
EMBEDDED SHORTWAVE TROUGHS. THE MOST NOTABLE ONE IS LOCATED NEAR
40N 135W.
SHORT TERM(TONIGHT-SUNDAY)...
FOR TONIGHT...THE AFOREMENTIONED SHORTWAVE TROUGH/VORT MAX IS STILL
FORECAST TO MOVE OVER THE REGION TONIGHT. GIVEN THE LINGERING
MOISTURE AND PASSING TROUGH WILL KEEP THE SLIGHT CHANCE FOR
SHOWERS IN FORECAST. THE NAM IS A LITTLE MORE ROBUST WITH THE
SHORTWAVE AND EVEN SHOWS SOME INSTABILITY ACROSS THE NORTH BAY.
THE CONSENSUS IN THE OFFICE IS THAT THE INSTABILITY IS A LITTLE
OVER DONE. NAM HAS RATHER MILD OVERNIGHT LOWS LIKELY CONTRIBUTING
TO THE HIGH SFC CAPE BEING FORECAST TONIGHT. IF PRECIP DOES FALL
OVERNIGHT NOT EXPECTING MUCH...ONLY A FEW ADDITIONAL HUNDREDTHS.
FRIDAY AND SATURDAY WILL FEATURE DRIER NORTHWEST FLOW WITH HIGH
PRESSURE BRIEFLY BUILDING IN. HIGH PRESSURE FLATTENS OUT AGAIN ON
SUNDAY AS AN UPPER LEVEL LOW DROPS SOUTH FROM THE GULF OF AK. MODEL
CONSENSUS IS SURPRISINGLY GOOD PASSING THE LOW JUST OFF THE COAST
DURING THE DAY SUNDAY. DEFINITELY NOT THE EASIEST FORECAST GIVEN
THE FORECAST TRACK...BUT FEEL CONFIDENT ENOUGH TO HAVE SHOWERS
DURING THE DAY SUNDAY. IN SOME CASES...THIS FORECAST TRACK OF THE
LOW WILL BRING THE BEST PRECIP TO THE COASTAL
MOUNTAINS...ESPECIALLY SANTA CRUZ AND MONTEREY. RAINFALL AMOUNTS
WILL LIKELY BE ON THE ORDER OF A FEW HUNDREDTHS TO A TENTH OR TWO.
THE UPPER LOW WILL MOVE FARTHER SOUTH SUNDAY NIGHT AND MOVE INLAND
EARLY MONDAY. BY THIS POINT ALL PRECIP WILL HAVE ENDED.
LONG TERM(MONDAY-THURSDAY)...
UPPER LEVEL RIDGING WILL REBUILD OVER THE EASTERN PACIFIC FOR MUCH
OF NEXT WEEK. SOME OF THE MEDIUM RANGE MODELS TRY TO BRING MORE
LIGHT PRECIP OVER THE PERIPHERY OF THE RIDGE MIDWEEK BUT CONF IS
TO LOW TO ADD ANY MENTION OF SHOWERS.
BEYOND THE FORECAST PERIOD....NEXT FRIDAY AND INTO THE WEEKEND THE
MODELS BREAK DOWN THE RIDGE AGAIN AND BRING MUCH NEEDED PRECIP TO THE
STATE. THE ECMWF IS THE WETTEST SOLUTION WITH THE GFS KEEPING MORE
PRECIP NORTH. ULTIMATELY...THE MAIN MESSAGE IS THAT THE PATTERN IS
CHANGING AND MORE STORMS ARE MOVING ACROSS THE REGION.
&&
.AVIATION...AS OF 9:45 PM PST THURSDAY...MORE RAIN IS BEING PICKED
UP OFFSHORE BY THE RADAR AND MORE MVFR CIGS ARE BEING REPORTED
AROUND THE SFO AND MRY BAY AREAS AS THE UPPER LEVEL SHORTWAVE
APPROACHES. WIND ARE ALSO PICKING UP WITH SFO REPORTING SUSTAINED
WINDS TO 20 KT. MVFR CIGS WILL BE PREDOMINANT UNTIL THE UPPER
TROUGH PASSES WHICH WILL BE AROUD 12Z. SHOULD CLEAR UP FOR THE
MORNING RUSH BUT CONFIDENCE IS NOT HIGH.
VICINITY OF KSFO...MOSTLY MVFR CIGS THROUGH 12Z WITH A FEW LIGHT
SHOWERS. WEST WINDS TO 20 KT DECREASING TO 10 KT AFTER 12Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CONDITIONS. ISOLATED LIGHT
SHOWERS 08Z=15Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PT ARENA TO PT REYES 10-60 NM
SCA...PT REYES TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PINOS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
&&
$$
PUBLIC FORECAST: RWW
AVIATION: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1036 PM MST THU JAN 30 2014
.UPDATE...
ISSUED AT 908 PM MST THU JAN 30 2014
MOST INTENSE SNOWFALL OCCURRING ACROSS NORTHERN PORTIONS OF THE
FORECAST AREA NOW WITH CDOT SHOWING HIGHWAY 50 CLOSED OVER MONARCH
PASS. THIS BAND EXTENDS EASTWARD ACROSS CHAFFEE LAKE COUNTIES AND
ACROSS NORTHERN EL PASO COUNTY. ECHOES LOOK PRETTY INTENSE ACROSS
NORTHERN EL PASO TOO...BUT WEB CAMS NOT LOOKING TO BAD YET AS
TEMPERATURES ARE HOVERING AROUND FREEZING. AM STARTING TO SEE SNOW
COVER AT MONUMENT HILL CAM. MODELS STILL ON TRACK FOR HEAVY SNOW
CONTINUING ALONG THE CONTINENTAL DIVIDE...WITH THE HEAVIEST
FALLING THROUGH 2 AM...THEN DECREASING AS THE FORCING SHIFTS EAST
OF THE AREA. STILL SOME DISCREPANCIES WITH SNOWFALL AMOUNTS ACROSS
NORTHERN EL PASO COUNTY WITH NAM SHOWING UP TO AN INCH
OVERNIGHT...AND GFS AROUND 3 TO 6 INCHES. RAP HAS BACKED OFF A BIT
AND IS SHOWING UP TO 2 INCHES OF ADDITIONAL SNOW ACROSS NORTHERN
EL PASO COUNTY WITH UP TO AN INCH ACROSS SOUTHERN PORTIONS OF THE
COUNTY. THIS SEEMS MORE IN LINE AS BEST ISENTROPIC LIFT SETS UP
JUST TO THE NORTH...BUT WILL CONTINUE TO MONITOR THIS CLOSELY
THROUGH THE EVENING AND MAKE ADJUSTMENTS AS NECESSARY. -KT
UPDATE ISSUED AT 547 PM MST THU JAN 30 2014
CURRENT FORECAST STILL LOOKS ON TRACK. BROUGHT IN THE LATEST GRIDS
FOR CURRENT CONDITIONS. CONCERN FOR FORECAST THIS EVENING WILL BE
ACROSS EL PASO COUNTY WHERE RUC13 AND GFS ARE SHOWING ADVISORY
TYPE SNOWFALL AMOUNTS ACROSS NORTHERN PORTIONS OF THE
COUNTY/MONUMENT HILL AREA...AND NAM12 SHOWS VERY LITTLE. WILL ALL
DEPEND ON WHERE THE BAND ASSOCIATED WITH THE STRONGER UPGLIDE SETS
UP. RADAR TRENDS FOCUSING HEAVIER SNOWFALL FARTHER NORTH ACROSS
NORTHEAST CO/DENVER AREA WHICH APPEARS TO BE MORE IN LINE WITH THE
NAM12 AND HRRR...SO WILL HOLD THE COURSE AND WAIT FOR LATEST 00Z
RUNS. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 300 PM MST THU JAN 30 2014
...SNOW...HEAVY AT TIMES...TO CONTINUE ACROSS THE CONTDVD...
CURRENT WATER VAPOR IMAGERY CONTINUES TO INDICATE AMPLE MID AND HIGH
LEVEL MOISTURE EMBEDDED WITHIN THE STRONG WESTERLY FLOW ALOFT ACROSS
THE REGION...AS A STRONG PACIFIC JET STREAM TRANSLATES ACROSS THE
GREAT BASIN AND INTO THE ROCKIES. REGIONAL RADARS INDICATING
WIDESPREAD ECHOES ACROSS WESTERN COLORADO IMPINGING ON THE
CONTDVD...WITH ECHOES SPREADING ACROSS THE UPPER ARKANSAS RIVER
VALLEY INTO EASTERN FREMONT AND WESTERN TELLER COUNTY AT THIS TIME.
AT SFC...A LOW NEAR RATON HAS EASTERLY LOW LEVEL FLOW DEEPENING
ACROSS THE EASTERN PLAINS AT THIS TIME. SOME EARLY TOTALS ACROSS THE
AREA FROM THIS MORNING INDICATED BETWEEN 1/2 AND 1 INCH OF SNOW
WATER EQUIVALENT AND BETWEEN 5 AND 15 INCHES OF SNOW HAS BEEN
RECORDED ACROSS THE CONTDVD...WITH THE HIGHEST TOTALS OVER AND NEAR
THE CENTRAL MTS.
TONIGHT AND TOMORROW...NO BIG CHANGES TO CURRENT FORECAST AS MOIST
JET STREAM CONTINUES TO TRANSLATE SOUTH AND EAST ACROSS THE STATE.
THIS WILL KEEP STRONG AND MOIST OROGRAPHIC FLOW IN PLACE ACROSS THE
CONTDVD. MODEL QPFS CONTINUE TO INDICATE ANOTHER 1/2 INCH TO 1 INCH
OF SNOW WATER EQUIVALENT ACROSS THE CONTDVD AREA THROUGH THE DAY
TOMORROW WITH THE HIGHEST TOTALS TRANSITIONING TO THE SOUTHWEST MTS
THROUGH THE DAY TOMORROW. NEEDLESS TO SAY...CURRENT WARNINGS AND
ADVISORIES TO REMAIN IN PLACE THROUGH THE DAY TOMORROW...WITH
ANOTHER 4 TO 18 INCHES OF SNOW EXPECTED FOR AREAS OVER AND NEAR THE
THE CONTDVD...GREATEST ACROSS THE HIGHER WEST FACING PEAKS.
STILL EXPECTING LIGHT SNOW FALL TO DEVELOP ACROSS THE HIGHER PEAKS
OF THE EASTERN MTS TONIGHT AND THROUGH THE DAY TOMORROW...AS THE JET
CONTINUES TO SAG ACROSS THE STATE...WITH GENERALLY 3 TO 6 INCHES
POSSIBLE ACROSS THE HIGHER PEAKS AND ONLY A FEW INCHES AT THE LOWER
ELEVATIONS. LATEST HIGHER RES MODELS CONTINUE TO TREND FURTHER NORTH
AND SLOW DOWN SNOW ACROSS THE PALMER DVD AND EASTERN PLAINS. WITH
THAT SAID...LOOKS LIKE WILL SEE SNOW LIGHT SNOW DEVELOPING ACROSS
THE PIKES REGION THIS AFTERNOON AND EARLY EVENING AS CURRENT ECHOES
ACROSS THE UPPER ARKANSAS RIVER CONTINUES TO MOVE EAST. ONLY
EXPECTED LIGHT ACCUMS OF UP TO AN INCH THIS EVENING WITH AREAS OF
LIGHT FLURRIES AND FOG CONTINUING THROUGH THE MORNING...AS SECONDARY
SURGE OF COLD AIR MOVES ACROSS THE PLAINS. LATEST MODELS DO INDICATE
ANOTHER ROUND OF SNOW DEVELOPING ACROSS THE PIKES REGION AGAIN INTO
FRIDAY AFTERNOON WITH AGAIN ONLY SOME LIGHT ACCUMS OF 1 TO 2
INCHES...WITH THE HIGHEST TOTALS ACROSS WESTERN AND NORTHERN
PORTIONS OF THE EL PASO COUNTY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 PM MST THU JAN 30 2014
...ACTIVE PATTERN TO CONTINUE AS 4 SYSTEMS ARE BEING TRACKED...
AN ACTIVE WEATHER PATTERN IS FORECAST TO CONTINUE THROUGH THE LONG
TERM PERIOD. SEVERAL WEATHER SYSTEMS WILL MOVE ACROSS THE REGION AND
THEY WILL BRING PERIODS OF SNOW TO THE FCST AREA. WITH THE
PRIMARY JET TO THE SOUTH OF THE REGION...TEMPS WILL LIKELY REMAIN
BELOW NORMAL ON THE PLAINS EACH DAY.
A WEATHER SYSTEM WILL BE MOVING OVER THE REGION AT THE BEGINNING OF
THIS PERIOD...FRIDAY NIGHT...AND THIS SYSTEM WILL LIKELY BRING SNOW
TO THE NORTHERN HALF OF THE SOUTHEAST PLAINS AS THE PRIMARY
BAROCLINIC ZONE WHICH IS LOCATED OVER NE CO AS I WRITE WILL BE
LOCATED OVER SE CO FRIDAY EVENING. THIS WILL PLACE THE PALMER DIVIDE
IN A FAVORABLE REGION FOR ACCUM SNOW. AT THIS TIME I HAVE ABOUT 3-6"
OF SNOW AFFECTING NORTHERN EL PASO COUNTY/TELLER COUNTY WITH 1-3"
FARTHER SOUTH ACROSS S EL PASO COUNTY. OVER THE REST OF THE PLAINS
IT DOES NOT APPEAR AT THIS TIME THAT SNOW WILL BE ALL THAT
HEAVY...WITH SNOW AMOUNTS MAINLY LESS THAN AN INCH. IT IS
POSSIBLE OTERO AND KIOWA COUNTIES COULD SEE A BIT MORE (1-2").
SNOW WILL END WEST TO EAST DURING THE EARLY MORNING HOURS
SATURDAY. THERE IS STILL SOME UNCERTAINTY ABOUT THIS FORECAST AND
IT IS NOT OUT OF THE QUESTION THAT WE COULD SEE MORE SNOW THAN
WHAT IS CURRENTLY BEING FORECAST. WINTER WX HILITES MAY BE NEEDED
FOR THE PIKES PEAK REGION LATE TOMORROW AFTERNOON AND EVENING.
STEADY SNOW WILL CONTINUE OVER THE CONTDVD FRIDAY NITE. HOWEVER THE
HEAVIEST SNOW WILL LIKELY FALL ACROSS THE W SLOPES OF THE SAN
JUANS...ESPECIALLY S OF WOLF CREEK PASS S TO THE CO/NM BORDER. BASED
ON THIS...I HAVE EXTENDED THE WSW FOR AREAS ALONG THE CONTDVD OUT
TO 06Z SAT (11 PM FRI NITE).
DURING THE DAY SATURDAY...SIMULATIONS HAVE BEEN SHOWING SOME
ADDITIONAL LIGHT SNOW FORMING ACROSS PARTS OF THE I-25 CORRIDOR
REGION/E SLOPES OF S MTNS SAT AFTERNOON AND MOVING EAST DURING
THE EVENING HOURS. THIS APPEARS TO BE ASSOCIATED WITH A NORTHERN
STREAM PIECE OF ENERGY MOVING ACROSS. FOR NOW HAVE INCREASED POPS
IN LOW END SCATTERED TO ACCOUNT FOR THIS ACTIVITY. OVER THE
MTNS...SNOW WILL BE MORE SHOWERY IN NATURE AND WILL GRADUALLY BE
DECREASING.
SUNDAY...IT WILL LIKELY BE DRY OVER THE ENTIRE FORECAST AREA AND
CONTINUED COOL. A WX SYSTEM WILL MOVE ACROSS NM...BUT IT APPEARS TOO
FAR SOUTH TO BRING THE AREA ANY PRECIP. WE WILL LIKELY SEE SOME
CIRRUS ASSOCIATED WITH IT THOUGH.
THE 3RD WEATHER SYSTEM WILL START TO AFFECT THE MOUNTAINS LATER ON
MONDAY AND LAST INTO TUESDAY. BOTH EC AND GFS ARE IN GOOD AGREEMENT WITH
THIS SYSTEM ALTHOUGH THE GFS QPF FIELDS ARE SIGNIFICANTLY MORE
WETTER THAN THE EC. IF THIS STORM DOES DEVELOP AS THE SIMULATIONS
INDICATE...THEN WE WILL HAVE ANOTHER CHANCE OF SOME WIDESPREAD
PRECIP OVER DROUGHT STRICKEN SOUTHEAST CO PLAINS. IT IS STILL TOO
EARLY TO KNOW HOW MUCH PRECIP WILL OCCUR WITH THIS SYSTEM.
ANOTHER WEATHER SYSTEM IS FCST TO AFFECT THE REGION ON THU. FOR NOW
JUST MENTIONED WIDESPREAD LIGHT POPS ACROSS THE ENTIRE FCST AREA.
BOTH SIMULATIONS ONCE AGAIN AGREE ON THIS SCENARIO...ALTHOUGH TIMING
IS OFF BY ABOUT 12H.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1000 PM MST THU JAN 30 2014
KCOS WILL SEE MVFR TO IFR CONDITIONS THROUGH THE NIGHT WITH WAVES
OF SNOW MOVING OFF THE MOUNTAINS AND ACROSS THE AREA AT TIMES.
COULD SEE UP 1/2 INCH TO AN INCH OF ACCUMULATION AT THE
TERMINAL...WITH THE HEAVIEST FALLING THROUGH 09Z. CIGS WILL LOWER
OVERNIGHT WITH THE SOUTHEAST WINDS AND COULD SEE A WINDOW OF UPPER
END LIFR CONDITIONS TOWARDS 12Z IN BR. CIGS WILL INCREASE A BIT
INTO THE LOW END MVFR CATEGORY FRIDAY MORNING...THEN ANOTHER WAVE
OF SNOW WILL MOVE OFF THE MOUNTAINS DURING THE AFTERNOON WITH
BOUTS OF IFR CIGS/VIS IN -SN THROUGH THE LATE AFTERNOON AND
EVENING. KCOS COULD SEE 1-2 INCHES OF SNOW WITH THIS SECOND ROUND
THROUGH FRIDAY NIGHT.
SNOW IS MORE LIKELY TO MISS THE KPUB AND KALS TAF SITES TONIGHT
THOUGH WILL CARRY A VCSH GROUP AT KALS OVERNIGHT AS THERE IS
A SLIGHTLY BETTER CHANCE THERE. CIGS WILL STAY VFR AT KALS...AND
MVFR AT KPUB. EASTERLY UPSLOPE FLOW AT KPUB WILL LIKELY CAUSE CIGS
TO DROP TOWARDS MORNING WITH THE POTENTIAL FOR SOME UPPER END IFR
CIGS WITH FOG TOWARDS 12Z. CIGS WILL INCREASE AGAIN DURING THE
LATE MORNING WITH A SLIGHTLY BETTER CHANCE AT SEEING A PASSING
-SHSN LATE FRIDAY AFTERNOON AND EVENING WITH THE SECOND WAVE
MOVING IN. KALS WILL LIKELY STAY VFR WITH BREEZY SOUTHWEST WINDS
15-25 KTS SPREADING IN DURING THE AFTERNOON.
MEANWHILE...CONTINENTAL DIVIDE WILL CONTINUE TO SEE WIDESPREAD MTN
OBSCURATIONS AND LIFR CONDITIONS IN +SN BLSN THROUGH THE NIGHT
WITH ANOTHER WAVE OF HEAVIER SNOW MOVING IN FRIDAY AFTERNOON. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST FRIDAY FOR COZ064-066-
067.
WINTER STORM WARNING UNTIL 11 PM MST FRIDAY FOR COZ058>061-068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST FRIDAY FOR COZ062-063.
&&
$$
UPDATE...KT
SHORT TERM...MW
LONG TERM...HODANISH/MW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
924 PM MST THU JAN 30 2014
.UPDATE...
ISSUED AT 908 PM MST THU JAN 30 2014
MOST INTENSE SNOWFALL OCCURRING ACROSS NORTHERN PORTIONS OF THE
FORECAST AREA NOW WITH CDOT SHOWING HIGHWAY 50 CLOSED OVER MONARCH
PASS. THIS BAND EXTENDS EASTWARD ACROSS CHAFFEE LAKE COUNTIES AND
ACROSS NORTHERN EL PASO COUNTY. ECHOES LOOK PRETTY INTENSE ACROSS
NORTHERN EL PASO TOO...BUT WEB CAMS NOT LOOKING TO BAD YET AS
TEMPERATURES ARE HOVERING AROUND FREEZING. AM STARTING TO SEE SNOW
COVER AT MONUMENT HILL CAM. MODELS STILL ON TRACK FOR HEAVY SNOW
CONTINUING ALONG THE CONTINENTAL DIVIDE...WITH THE HEAVIEST
FALLING THROUGH 2 AM...THEN DECREASING AS THE FORCING SHIFTS EAST
OF THE AREA. STILL SOME DISCREPANCIES WITH SNOWFALL AMOUNTS ACROSS
NORTHERN EL PASO COUNTY WITH NAM SHOWING UP TO AN INCH
OVERNIGHT...AND GFS AROUND 3 TO 6 INCHES. RAP HAS BACKED OFF A BIT
AND IS SHOWING UP TO 2 INCHES OF ADDITIONAL SNOW ACROSS NORTHERN
EL PASO COUNTY WITH UP TO AN INCH ACROSS SOUTHERN PORTIONS OF THE
COUNTY. THIS SEEMS MORE IN LINE AS BEST ISENTROPIC LIFT SETS UP
JUST TO THE NORTH...BUT WILL CONTINUE TO MONITOR THIS CLOSELY
THROUGH THE EVENING AND MAKE ADJUSTMENTS AS NECESSARY. -KT
UPDATE ISSUED AT 547 PM MST THU JAN 30 2014
CURRENT FORECAST STILL LOOKS ON TRACK. BROUGHT IN THE LATEST GRIDS
FOR CURRENT CONDITIONS. CONCERN FOR FORECAST THIS EVENING WILL BE
ACROSS EL PASO COUNTY WHERE RUC13 AND GFS ARE SHOWING ADVISORY
TYPE SNOWFALL AMOUNTS ACROSS NORTHERN PORTIONS OF THE
COUNTY/MONUMENT HILL AREA...AND NAM12 SHOWS VERY LITTLE. WILL ALL
DEPEND ON WHERE THE BAND ASSOCIATED WITH THE STRONGER UPGLIDE SETS
UP. RADAR TRENDS FOCUSING HEAVIER SNOWFALL FARTHER NORTH ACROSS
NORTHEAST CO/DENVER AREA WHICH APPEARS TO BE MORE IN LINE WITH THE
NAM12 AND HRRR...SO WILL HOLD THE COURSE AND WAIT FOR LATEST 00Z
RUNS. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 300 PM MST THU JAN 30 2014
...SNOW...HEAVY AT TIMES...TO CONTINUE ACROSS THE CONTDVD...
CURRENT WATER VAPOR IMAGERY CONTINUES TO INDICATE AMPLE MID AND HIGH
LEVEL MOISTURE EMBEDDED WITHIN THE STRONG WESTERLY FLOW ALOFT ACROSS
THE REGION...AS A STRONG PACIFIC JET STREAM TRANSLATES ACROSS THE
GREAT BASIN AND INTO THE ROCKIES. REGIONAL RADARS INDICATING
WIDESPREAD ECHOES ACROSS WESTERN COLORADO IMPINGING ON THE
CONTDVD...WITH ECHOES SPREADING ACROSS THE UPPER ARKANSAS RIVER
VALLEY INTO EASTERN FREMONT AND WESTERN TELLER COUNTY AT THIS TIME.
AT SFC...A LOW NEAR RATON HAS EASTERLY LOW LEVEL FLOW DEEPENING
ACROSS THE EASTERN PLAINS AT THIS TIME. SOME EARLY TOTALS ACROSS THE
AREA FROM THIS MORNING INDICATED BETWEEN 1/2 AND 1 INCH OF SNOW
WATER EQUIVALENT AND BETWEEN 5 AND 15 INCHES OF SNOW HAS BEEN
RECORDED ACROSS THE CONTDVD...WITH THE HIGHEST TOTALS OVER AND NEAR
THE CENTRAL MTS.
TONIGHT AND TOMORROW...NO BIG CHANGES TO CURRENT FORECAST AS MOIST
JET STREAM CONTINUES TO TRANSLATE SOUTH AND EAST ACROSS THE STATE.
THIS WILL KEEP STRONG AND MOIST OROGRAPHIC FLOW IN PLACE ACROSS THE
CONTDVD. MODEL QPFS CONTINUE TO INDICATE ANOTHER 1/2 INCH TO 1 INCH
OF SNOW WATER EQUIVALENT ACROSS THE CONTDVD AREA THROUGH THE DAY
TOMORROW WITH THE HIGHEST TOTALS TRANSITIONING TO THE SOUTHWEST MTS
THROUGH THE DAY TOMORROW. NEEDLESS TO SAY...CURRENT WARNINGS AND
ADVISORIES TO REMAIN IN PLACE THROUGH THE DAY TOMORROW...WITH
ANOTHER 4 TO 18 INCHES OF SNOW EXPECTED FOR AREAS OVER AND NEAR THE
THE CONTDVD...GREATEST ACROSS THE HIGHER WEST FACING PEAKS.
STILL EXPECTING LIGHT SNOW FALL TO DEVELOP ACROSS THE HIGHER PEAKS
OF THE EASTERN MTS TONIGHT AND THROUGH THE DAY TOMORROW...AS THE JET
CONTINUES TO SAG ACROSS THE STATE...WITH GENERALLY 3 TO 6 INCHES
POSSIBLE ACROSS THE HIGHER PEAKS AND ONLY A FEW INCHES AT THE LOWER
ELEVATIONS. LATEST HIGHER RES MODELS CONTINUE TO TREND FURTHER NORTH
AND SLOW DOWN SNOW ACROSS THE PALMER DVD AND EASTERN PLAINS. WITH
THAT SAID...LOOKS LIKE WILL SEE SNOW LIGHT SNOW DEVELOPING ACROSS
THE PIKES REGION THIS AFTERNOON AND EARLY EVENING AS CURRENT ECHOES
ACROSS THE UPPER ARKANSAS RIVER CONTINUES TO MOVE EAST. ONLY
EXPECTED LIGHT ACCUMS OF UP TO AN INCH THIS EVENING WITH AREAS OF
LIGHT FLURRIES AND FOG CONTINUING THROUGH THE MORNING...AS SECONDARY
SURGE OF COLD AIR MOVES ACROSS THE PLAINS. LATEST MODELS DO INDICATE
ANOTHER ROUND OF SNOW DEVELOPING ACROSS THE PIKES REGION AGAIN INTO
FRIDAY AFTERNOON WITH AGAIN ONLY SOME LIGHT ACCUMS OF 1 TO 2
INCHES...WITH THE HIGHEST TOTALS ACROSS WESTERN AND NORTHERN
PORTIONS OF THE EL PASO COUNTY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 PM MST THU JAN 30 2014
...ACTIVE PATTERN TO CONTINUE AS 4 SYSTEMS ARE BEING TRACKED...
AN ACTIVE WEATHER PATTERN IS FORECAST TO CONTINUE THROUGH THE LONG
TERM PERIOD. SEVERAL WEATHER SYSTEMS WILL MOVE ACROSS THE REGION AND
THEY WILL BRING PERIODS OF SNOW TO THE FCST AREA. WITH THE
PRIMARY JET TO THE SOUTH OF THE REGION...TEMPS WILL LIKELY REMAIN
BELOW NORMAL ON THE PLAINS EACH DAY.
A WEATHER SYSTEM WILL BE MOVING OVER THE REGION AT THE BEGINNING OF
THIS PERIOD...FRIDAY NIGHT...AND THIS SYSTEM WILL LIKELY BRING SNOW
TO THE NORTHERN HALF OF THE SOUTHEAST PLAINS AS THE PRIMARY
BAROCLINIC ZONE WHICH IS LOCATED OVER NE CO AS I WRITE WILL BE
LOCATED OVER SE CO FRIDAY EVENING. THIS WILL PLACE THE PALMER DIVIDE
IN A FAVORABLE REGION FOR ACCUM SNOW. AT THIS TIME I HAVE ABOUT 3-6"
OF SNOW AFFECTING NORTHERN EL PASO COUNTY/TELLER COUNTY WITH 1-3"
FARTHER SOUTH ACROSS S EL PASO COUNTY. OVER THE REST OF THE PLAINS
IT DOES NOT APPEAR AT THIS TIME THAT SNOW WILL BE ALL THAT
HEAVY...WITH SNOW AMOUNTS MAINLY LESS THAN AN INCH. IT IS
POSSIBLE OTERO AND KIOWA COUNTIES COULD SEE A BIT MORE (1-2").
SNOW WILL END WEST TO EAST DURING THE EARLY MORNING HOURS
SATURDAY. THERE IS STILL SOME UNCERTAINTY ABOUT THIS FORECAST AND
IT IS NOT OUT OF THE QUESTION THAT WE COULD SEE MORE SNOW THAN
WHAT IS CURRENTLY BEING FORECAST. WINTER WX HILITES MAY BE NEEDED
FOR THE PIKES PEAK REGION LATE TOMORROW AFTERNOON AND EVENING.
STEADY SNOW WILL CONTINUE OVER THE CONTDVD FRIDAY NITE. HOWEVER THE
HEAVIEST SNOW WILL LIKELY FALL ACROSS THE W SLOPES OF THE SAN
JUANS...ESPECIALLY S OF WOLF CREEK PASS S TO THE CO/NM BORDER. BASED
ON THIS...I HAVE EXTENDED THE WSW FOR AREAS ALONG THE CONTDVD OUT
TO 06Z SAT (11 PM FRI NITE).
DURING THE DAY SATURDAY...SIMULATIONS HAVE BEEN SHOWING SOME
ADDITIONAL LIGHT SNOW FORMING ACROSS PARTS OF THE I-25 CORRIDOR
REGION/E SLOPES OF S MTNS SAT AFTERNOON AND MOVING EAST DURING
THE EVENING HOURS. THIS APPEARS TO BE ASSOCIATED WITH A NORTHERN
STREAM PIECE OF ENERGY MOVING ACROSS. FOR NOW HAVE INCREASED POPS
IN LOW END SCATTERED TO ACCOUNT FOR THIS ACTIVITY. OVER THE
MTNS...SNOW WILL BE MORE SHOWERY IN NATURE AND WILL GRADUALLY BE
DECREASING.
SUNDAY...IT WILL LIKELY BE DRY OVER THE ENTIRE FORECAST AREA AND
CONTINUED COOL. A WX SYSTEM WILL MOVE ACROSS NM...BUT IT APPEARS TOO
FAR SOUTH TO BRING THE AREA ANY PRECIP. WE WILL LIKELY SEE SOME
CIRRUS ASSOCIATED WITH IT THOUGH.
THE 3RD WEATHER SYSTEM WILL START TO AFFECT THE MOUNTAINS LATER ON
MONDAY AND LAST INTO TUESDAY. BOTH EC AND GFS ARE IN GOOD AGREEMENT WITH
THIS SYSTEM ALTHOUGH THE GFS QPF FIELDS ARE SIGNIFICANTLY MORE
WETTER THAN THE EC. IF THIS STORM DOES DEVELOP AS THE SIMULATIONS
INDICATE...THEN WE WILL HAVE ANOTHER CHANCE OF SOME WIDESPREAD
PRECIP OVER DROUGHT STRICKEN SOUTHEAST CO PLAINS. IT IS STILL TOO
EARLY TO KNOW HOW MUCH PRECIP WILL OCCUR WITH THIS SYSTEM.
ANOTHER WEATHER SYSTEM IS FCST TO AFFECT THE REGION ON THU. FOR NOW
JUST MENTIONED WIDESPREAD LIGHT POPS ACROSS THE ENTIRE FCST AREA.
BOTH SIMULATIONS ONCE AGAIN AGREE ON THIS SCENARIO...ALTHOUGH TIMING
IS OFF BY ABOUT 12H.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 300 PM MST THU JAN 30 2014
MVFR CONDITIONS AT COS THROUGH THE EVENING WITH BRIEF IFR CIGS AND
VIS WITH OCCASIONAL LIGHT SNOW...WITH ACCUMS ON RUNWAYS OF GENERALLY
LESS THAN AN INCH. EXPECTING LOWERING CIGS WITH LIGHT FLURRIES AND
FOG DEVELOPING THROUGH THE OVERNIGHT. MVFR AND IFR CONDITIONS TO
PERSIST THROUGH THE DAY FRIDAY WITH LIGHT SNOW DEVELOPING AGAIN IN
THE AFTERNOON.
VFR CONDITIONS AT PUB THROUGH 06Z WITH LOWERING CIGS AND POSSIBLE
FOG DEVELOPING INTO EARLY FRIDAY MORNING. MVFR CIGS TO REMAIN
POSSIBLE THROUGH THE DAY ON FRIDAY.
VFR CONDITIONS WITH BREEZY WEST TO SOUTHWEST WINDS EXPECTED AT
ALS WITH PRECIPITATION REMAINING ACROSS THE HIGHER TERRAIN THROUGH
THE PERIOD.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST FRIDAY FOR COZ064-066-
067.
WINTER STORM WARNING UNTIL 11 PM MST FRIDAY FOR COZ058>061-068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST FRIDAY FOR COZ062-063.
&&
$$
UPDATE...KT
SHORT TERM...MW
LONG TERM...HODANISH/MW
AVIATION...MW
AREA FORECAST DISCUSSION
NWS MIAMI FL
1252 PM EST FRI JAN 31 2014
.AVIATION...
THE LOW STRATUS CEILINGS THAT PREVAILED ACROSS MOST OF THE
TERMINALS EARLIER THIS MORNING ARE SLOWLY STARTING TO LIFT AS THE
AFTERNOON PROGRESSES. GRADUAL CLEARING ACROSS THE REGION SHOULD ALLOW
SUFFICIENT AFTERNOON HEATING FOR SHOWERS THIS AFTERNOON...WITH
ALL TERMINALS ASSIGNED VCSH THROUGH 00Z THIS EVENING. THIS MAY
ALSO ALLOW A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON OR EARLY
EVENING...MAINLY FOR ATLANTIC COAST TERMINALS BUT NOT ENOUGH
CONFIDENCE TO ASSIGN VCTS. BRIEF PERIODS OF NEAR IFR CONDITIONS
MAY BE POSSIBLE WITH SHOWERS. MAINLY SOUTHEASTERLY WINDS EXPECTED
TO PREVAIL THROUGH FORECAST PERIOD. SATURATED GROUNDS MAY ALLOW
FOR FOG DEVELOPMENT TONIGHT...MAINLY INTERIOR AND WEST WITH
TERMINALS LIKELY TO BE AFFECTED INCLUDING KTMB AND KAPF AND
INCLUDED IN THOSE TAF`S.
60
&&
.PREV DISCUSSION... /ISSUED 947 AM EST FRI JAN 31 2014/
UPDATE...
HAVE MADE SOME ADJUSTMENTS TO THE SHORT TERM FORECAST THROUGH THIS
AFTERNOON BASED ON CURRENT TRENDS. THERE HAVE BEEN SOME THINNING
OF THE CLOUD COVER ALLOWING FOR SOME PEAKS OF SUNSHINE ESPECIALLY
OVER THE EASTERN HALF OF THE PENINSULA WITH THE 12Z MFL SOUNDING
ALSO SHOWING SOME LOW LEVEL INSTABILITY AND A MUCH LESS PRONOUNCED
SURFACE BASED INVERSION THAN YESTERDAY MORNING. ALL OF THIS
COMBINED WITH PLENTY OF LOW TO MID LEVEL MOISTURE COULD LEAD TO
SOME ISOLATED THUNDERSTORMS THIS AFTERNOON. THE MID LEVEL LAPSE
RATES ARE VERY MEAGER BUT WITH APPROACH OF THE TROUGH IN THE
EASTERN GULF OF MEXICO WILL ADD TO SOME OF THE UPPER DYNAMICS. THE
HRRR INITIALIZED VERY WELL THIS MORNING AND SHOWS SCATTERED
CONVECTION DEVELOPING AROUND 16Z MOSTLY EAST OF U.S. 27 AND NORTH
OF TAMIAMI TRAIL. THIS SEEM REASONABLE GIVEN THE ABOVE REASONING
AND THE SOUTHWEST STEERING FLOW. CONVECTIVE PARAMETERS ARE NOT
HOWEVER VERY IMPRESSIVE SO A FEW LIGHTNING STRIKES APPEAR TO BE
THE ONLY THREAT AT THIS TIME.
KOB
PREV DISCUSSION... /ISSUED 632 AM EST FRI JAN 31 2014/
AVIATION...
FEEL THAT BY 12Z...EASTERN TERMINALS WILL BE IN MVFR CIGS...WITH
NAPLES CLINGING TO IFR STRATUS FOR A FEW MORE HOURS. BY
AFTERNOON...MOST AREAS SHOULD SEE SOME CLEARING...AND WENT
ACROSS-THE-BOARD VFR BY 18Z. SCATTERED SHOWERS EXPECTED THROUGH THIS
AFTERNOON...BUT BEYOND 6 HOURS OUT...CONFIDENCE WASNT QUITE ENOUGH
TO TRIGGER VCSH WORDING. TONIGHT...MODELS HINTING AT FAIRLY
WIDESPREAD FOG/STRATUS EPISODE OVER AT LEAST INTERIOR SOUTH FLORIDA.
FOR NOW HAVE LEFT EASTERN TERMINALS RESTRICTION-FREE...BUT KTMB WILL
NEED TO BE WATCHED CLOSELY. AT NAPLES...VSBY AND CIGS BOTH LOWER TO
MVFR LEVELS AFTER 6Z OR SO SATURDAY. WINDS LIGHT AND NORTHEAST
TODAY...GRADUALLY VEERING TO EAST-SOUTHEAST. /SK
PREV DISCUSSION... /ISSUED 251 AM EST FRI JAN 31 2014/
SHORT TERM (TODAY-SUNDAY)...
THE LATEST MODEL GUIDANCE REMAINS PERSISTENT AND IN GOOD AGREEMENT
AND GENERALLY INDICATES A GRADUAL DRYING TREND AS HIGH PRESSURE
BUILDS BACK ACROSS THE REGION THROUGH THE COURSE OF THE WEEKEND. THE
DEEP LAYER MOISTURE AXIS AND FRONTAL BOUNDARY DRAPED ACROSS S
FL/KEYS/STRAITS THAT HAVE BROUGHT THE WET CONDITIONS TO THE AREA
OVER THE PAST FEW DAYS ARE FORECAST TO LIFT NORTH AS A SHORTWAVE
TROUGH TRANSLATES EWD OVER THE STATE TODAY. THE LATEST HRRR AND WRF
MODEL GUIDANCE HAVE INITIALIZED WELL WITH THE CURRENT CONDITIONS AND
REFLECT THIS DRYING TREND ACROSS THE AREA TODAY AFTER ANOTHER WET
START THIS MORNING. MODEL PWS DECREASE FROM AROUND AND JUST UNDER
THE 2" MARK THIS MORNING TO THE 1-1.5" RANGE EARLY SATURDAY MORNING.
RISING UPPER HEIGHTS COMBINED WITH THIS DRYING TREND WILL ALLOW THE
CLOUDS TO CLEAR OUT THROUGH THE PERIOD. WINDS ARE FORECAST TO REMAIN
OUT OF THE SOUTHEAST THROUGH THE WEEKEND AS THE SURFACE RIDGE AXIS
SETS UP ACROSS CENTRAL FLORIDA FROM EAST TO WEST. TEMPERATURES ARE
FORECAST TO REMAIN AROUND 5 TO 10 DEG WARMER THAN AVERAGE EACH DAY.
FOG WILL BECOME A POSSIBILITY THROUGH THE OVERNIGHT PERIOD TONIGHT
THROUGH SATURDAY MORNING DUE TO THE EXPECTED CLEARING...NEAR CALM
WINDS AND LOW-LEVEL MOISTURE. THE NAM12 CONDENSATION PRESSURE
DEFICITS REFLECT THIS AND ARE QUITE LOW ACROSS MUCH OF THE INTERIOR
AREAS TONIGHT INTO SATURDAY MORNING. THE SREF PROBABILITY OF VSBYS
DROPPING BELOW 1 MILE RANGE FROM 60-90%.
LONG TERM (SUNDAY NIGHT-THURSDAY)...
THE EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT AND INDICATES
DRIER AND WARMER CONDITIONS ASSOCIATED WITH A DEEP LAYER RIDGE OVER
THE STATE. TEMPERATURES ARE FORECAST TO REMAIN ABOVE AVERAGE WITH
HIGHS FORECAST TO REACH THE LOW TO MID 80S EACH DAY AND LOWS
FORECAST TO REACH THE LOW 60S EACH NIGHT ACROSS THE INTERIOR
LOCATIONS (LOW 70S FOR COASTAL/METRO LOCATIONS). GFS ENSEMBLE
MEAN/GFS/ECMWF ARE INDICATING A COLD FRONT MOVING INTO THE REGION BY
THE END OF THE PERIOD AND STALLING NORTH OF OUR AREA.
MARINE...
A DRYING TREND IS EXPECTED THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK AS A FRONTAL BOUNDARY LIFTS NORTH AND HIGH PRESSURE BUILDS BACK
ACROSS THE MARINE AREA. WINDS AND SEAS WILL REMAIN BELOW
CAUTIONARY/ADVISORY LEVELS THROUGH THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 69 83 69 82 / 20 10 10 -
FORT LAUDERDALE 71 82 73 82 / 20 10 10 -
MIAMI 71 83 72 82 / 20 10 10 -
NAPLES 66 84 66 84 / 20 10 10 -
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
947 AM EST FRI JAN 31 2014
.UPDATE...
HAVE MADE SOME ADJUSTMENTS TO THE SHORT TERM FORECAST THROUGH THIS
AFTERNOON BASED ON CURRENT TRENDS. THERE HAVE BEEN SOME THINNING
OF THE CLOUD COVER ALLOWING FOR SOME PEAKS OF SUNSHINE ESPECIALLY
OVER THE EASTERN HALF OF THE PENINSULA WITH THE 12Z MFL SOUNDING
ALSO SHOWING SOME LOW LEVEL INSTABILITY AND A MUCH LESS PRONOUNCED
SURFACE BASED INVERSION THAN YESTERDAY MORNING. ALL OF THIS
COMBINED WITH PLENTY OF LOW TO MID LEVEL MOISTURE COULD LEAD TO
SOME ISOLATED THUNDERSTORMS THIS AFTERNOON. THE MID LEVEL LAPSE
RATES ARE VERY MEAGER BUT WITH APPROACH OF THE TROUGH IN THE
EASTERN GULF OF MEXICO WILL ADD TO SOME OF THE UPPER DYNAMICS. THE
HRRR INITIALIZED VERY WELL THIS MORNING AND SHOWS SCATTERED
CONVECTION DEVELOPING AROUND 16Z MOSTLY EAST OF U.S. 27 AND NORTH
OF TAMIAMI TRAIL. THIS SEEM REASONABLE GIVEN THE ABOVE REASONING
AND THE SOUTHWEST STEERING FLOW. CONVECTIVE PARAMETERS ARE NOT
HOWEVER VERY IMPRESSIVE SO A FEW LIGHTNING STRIKES APPEAR TO BE
THE ONLY THREAT AT THIS TIME.
KOB
&&
.PREV DISCUSSION... /ISSUED 632 AM EST FRI JAN 31 2014/
AVIATION...
FEEL THAT BY 12Z...EASTERN TERMINALS WILL BE IN MVFR CIGS...WITH
NAPLES CLINGING TO IFR STRATUS FOR A FEW MORE HOURS. BY
AFTERNOON...MOST AREAS SHOULD SEE SOME CLEARING...AND WENT
ACROSS-THE-BOARD VFR BY 18Z. SCATTERED SHOWERS EXPECTED THROUGH THIS
AFTERNOON...BUT BEYOND 6 HOURS OUT...CONFIDENCE WASNT QUITE ENOUGH
TO TRIGGER VCSH WORDING. TONIGHT...MODELS HINTING AT FAIRLY
WIDESPREAD FOG/STRATUS EPISODE OVER AT LEAST INTERIOR SOUTH FLORIDA.
FOR NOW HAVE LEFT EASTERN TERMINALS RESTRICTION-FREE...BUT KTMB WILL
NEED TO BE WATCHED CLOSELY. AT NAPLES...VSBY AND CIGS BOTH LOWER TO
MVFR LEVELS AFTER 6Z OR SO SATURDAY. WINDS LIGHT AND NORTHEAST
TODAY...GRADUALLY VEERING TO EAST-SOUTHEAST. /SK
PREV DISCUSSION... /ISSUED 251 AM EST FRI JAN 31 2014/
SHORT TERM (TODAY-SUNDAY)...
THE LATEST MODEL GUIDANCE REMAINS PERSISTENT AND IN GOOD AGREEMENT
AND GENERALLY INDICATES A GRADUAL DRYING TREND AS HIGH PRESSURE
BUILDS BACK ACROSS THE REGION THROUGH THE COURSE OF THE WEEKEND. THE
DEEP LAYER MOISTURE AXIS AND FRONTAL BOUNDARY DRAPED ACROSS S
FL/KEYS/STRAITS THAT HAVE BROUGHT THE WET CONDITIONS TO THE AREA
OVER THE PAST FEW DAYS ARE FORECAST TO LIFT NORTH AS A SHORTWAVE
TROUGH TRANSLATES EWD OVER THE STATE TODAY. THE LATEST HRRR AND WRF
MODEL GUIDANCE HAVE INITIALIZED WELL WITH THE CURRENT CONDITIONS AND
REFLECT THIS DRYING TREND ACROSS THE AREA TODAY AFTER ANOTHER WET
START THIS MORNING. MODEL PWS DECREASE FROM AROUND AND JUST UNDER
THE 2" MARK THIS MORNING TO THE 1-1.5" RANGE EARLY SATURDAY MORNING.
RISING UPPER HEIGHTS COMBINED WITH THIS DRYING TREND WILL ALLOW THE
CLOUDS TO CLEAR OUT THROUGH THE PERIOD. WINDS ARE FORECAST TO REMAIN
OUT OF THE SOUTHEAST THROUGH THE WEEKEND AS THE SURFACE RIDGE AXIS
SETS UP ACROSS CENTRAL FLORIDA FROM EAST TO WEST. TEMPERATURES ARE
FORECAST TO REMAIN AROUND 5 TO 10 DEG WARMER THAN AVERAGE EACH DAY.
FOG WILL BECOME A POSSIBILITY THROUGH THE OVERNIGHT PERIOD TONIGHT
THROUGH SATURDAY MORNING DUE TO THE EXPECTED CLEARING...NEAR CALM
WINDS AND LOW-LEVEL MOISTURE. THE NAM12 CONDENSATION PRESSURE
DEFICITS REFLECT THIS AND ARE QUITE LOW ACROSS MUCH OF THE INTERIOR
AREAS TONIGHT INTO SATURDAY MORNING. THE SREF PROBABILITY OF VSBYS
DROPPING BELOW 1 MILE RANGE FROM 60-90%.
LONG TERM (SUNDAY NIGHT-THURSDAY)...
THE EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT AND INDICATES
DRIER AND WARMER CONDITIONS ASSOCIATED WITH A DEEP LAYER RIDGE OVER
THE STATE. TEMPERATURES ARE FORECAST TO REMAIN ABOVE AVERAGE WITH
HIGHS FORECAST TO REACH THE LOW TO MID 80S EACH DAY AND LOWS
FORECAST TO REACH THE LOW 60S EACH NIGHT ACROSS THE INTERIOR
LOCATIONS (LOW 70S FOR COASTAL/METRO LOCATIONS). GFS ENSEMBLE
MEAN/GFS/ECMWF ARE INDICATING A COLD FRONT MOVING INTO THE REGION BY
THE END OF THE PERIOD AND STALLING NORTH OF OUR AREA.
MARINE...
A DRYING TREND IS EXPECTED THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK AS A FRONTAL BOUNDARY LIFTS NORTH AND HIGH PRESSURE BUILDS BACK
ACROSS THE MARINE AREA. WINDS AND SEAS WILL REMAIN BELOW
CAUTIONARY/ADVISORY LEVELS THROUGH THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 69 83 69 / 40 20 10 10
FORT LAUDERDALE 81 71 82 73 / 40 20 10 10
MIAMI 82 71 83 72 / 40 20 10 10
NAPLES 79 66 84 66 / 40 20 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
632 AM EST FRI JAN 31 2014
.AVIATION...
FEEL THAT BY 12Z...EASTERN TERMINALS WILL BE IN MVFR CIGS...WITH
NAPLES CLINGING TO IFR STRATUS FOR A FEW MORE HOURS. BY
AFTERNOON...MOST AREAS SHOULD SEE SOME CLEARING...AND WENT
ACROSS-THE-BOARD VFR BY 18Z. SCATTERED SHOWERS EXPECTED THROUGH THIS
AFTERNOON...BUT BEYOND 6 HOURS OUT...CONFIDENCE WASNT QUITE ENOUGH
TO TRIGGER VCSH WORDING. TONIGHT...MODELS HINTING AT FAIRLY
WIDESPREAD FOG/STRATUS EPISODE OVER AT LEAST INTERIOR SOUTH FLORIDA.
FOR NOW HAVE LEFT EASTERN TERMINALS RESTRICTION-FREE...BUT KTMB WILL
NEED TO BE WATCHED CLOSELY. AT NAPLES...VSBY AND CIGS BOTH LOWER TO
MVFR LEVELS AFTER 6Z OR SO SATURDAY. WINDS LIGHT AND NORTHEAST
TODAY...GRADUALLY VEERING TO EAST-SOUTHEAST. /SK
&&
.PREV DISCUSSION... /ISSUED 251 AM EST FRI JAN 31 2014/
SHORT TERM (TODAY-SUNDAY)...
THE LATEST MODEL GUIDANCE REMAINS PERSISTENT AND IN GOOD AGREEMENT
AND GENERALLY INDICATES A GRADUAL DRYING TREND AS HIGH PRESSURE
BUILDS BACK ACROSS THE REGION THROUGH THE COURSE OF THE WEEKEND. THE
DEEP LAYER MOISTURE AXIS AND FRONTAL BOUNDARY DRAPED ACROSS S
FL/KEYS/STRAITS THAT HAVE BROUGHT THE WET CONDITIONS TO THE AREA
OVER THE PAST FEW DAYS ARE FORECAST TO LIFT NORTH AS A SHORTWAVE
TROUGH TRANSLATES EWD OVER THE STATE TODAY. THE LATEST HRRR AND WRF
MODEL GUIDANCE HAVE INITIALIZED WELL WITH THE CURRENT CONDITIONS AND
REFLECT THIS DRYING TREND ACROSS THE AREA TODAY AFTER ANOTHER WET
START THIS MORNING. MODEL PWS DECREASE FROM AROUND AND JUST UNDER
THE 2" MARK THIS MORNING TO THE 1-1.5" RANGE EARLY SATURDAY MORNING.
RISING UPPER HEIGHTS COMBINED WITH THIS DRYING TREND WILL ALLOW THE
CLOUDS TO CLEAR OUT THROUGH THE PERIOD. WINDS ARE FORECAST TO REMAIN
OUT OF THE SOUTHEAST THROUGH THE WEEKEND AS THE SURFACE RIDGE AXIS
SETS UP ACROSS CENTRAL FLORIDA FROM EAST TO WEST. TEMPERATURES ARE
FORECAST TO REMAIN AROUND 5 TO 10 DEG WARMER THAN AVERAGE EACH DAY.
FOG WILL BECOME A POSSIBILITY THROUGH THE OVERNIGHT PERIOD TONIGHT
THROUGH SATURDAY MORNING DUE TO THE EXPECTED CLEARING...NEAR CALM
WINDS AND LOW-LEVEL MOISTURE. THE NAM12 CONDENSATION PRESSURE
DEFICITS REFLECT THIS AND ARE QUITE LOW ACROSS MUCH OF THE INTERIOR
AREAS TONIGHT INTO SATURDAY MORNING. THE SREF PROBABILITY OF VSBYS
DROPPING BELOW 1 MILE RANGE FROM 60-90%.
LONG TERM (SUNDAY NIGHT-THURSDAY)...
THE EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT AND INDICATES
DRIER AND WARMER CONDITIONS ASSOCIATED WITH A DEEP LAYER RIDGE OVER
THE STATE. TEMPERATURES ARE FORECAST TO REMAIN ABOVE AVERAGE WITH
HIGHS FORECAST TO REACH THE LOW TO MID 80S EACH DAY AND LOWS
FORECAST TO REACH THE LOW 60S EACH NIGHT ACROSS THE INTERIOR
LOCATIONS (LOW 70S FOR COASTAL/METRO LOCATIONS). GFS ENSEMBLE
MEAN/GFS/ECMWF ARE INDICATING A COLD FRONT MOVING INTO THE REGION BY
THE END OF THE PERIOD AND STALLING NORTH OF OUR AREA.
MARINE...
A DRYING TREND IS EXPECTED THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK AS A FRONTAL BOUNDARY LIFTS NORTH AND HIGH PRESSURE BUILDS BACK
ACROSS THE MARINE AREA. WINDS AND SEAS WILL REMAIN BELOW
CAUTIONARY/ADVISORY LEVELS THROUGH THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 69 83 69 / 40 20 10 10
FORT LAUDERDALE 81 71 82 73 / 40 20 10 10
MIAMI 82 71 83 72 / 40 20 10 10
NAPLES 79 66 84 66 / 40 20 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
251 AM EST FRI JAN 31 2014
.SHORT TERM (TODAY-SUNDAY)...
THE LATEST MODEL GUIDANCE REMAINS PERSISTENT AND IN GOOD AGREEMENT
AND GENERALLY INDICATES A GRADUAL DRYING TREND AS HIGH PRESSURE
BUILDS BACK ACROSS THE REGION THROUGH THE COURSE OF THE WEEKEND. THE
DEEP LAYER MOISTURE AXIS AND FRONTAL BOUNDARY DRAPED ACROSS S
FL/KEYS/STRAITS THAT HAVE BROUGHT THE WET CONDITIONS TO THE AREA
OVER THE PAST FEW DAYS ARE FORECAST TO LIFT NORTH AS A SHORTWAVE
TROUGH TRANSLATES EWD OVER THE STATE TODAY. THE LATEST HRRR AND WRF
MODEL GUIDANCE HAVE INITIALIZED WELL WITH THE CURRENT CONDITIONS AND
REFLECT THIS DRYING TREND ACROSS THE AREA TODAY AFTER ANOTHER WET
START THIS MORNING. MODEL PWS DECREASE FROM AROUND AND JUST UNDER
THE 2" MARK THIS MORNING TO THE 1-1.5" RANGE EARLY SATURDAY MORNING.
RISING UPPER HEIGHTS COMBINED WITH THIS DRYING TREND WILL ALLOW THE
CLOUDS TO CLEAR OUT THROUGH THE PERIOD. WINDS ARE FORECAST TO REMAIN
OUT OF THE SOUTHEAST THROUGH THE WEEKEND AS THE SURFACE RIDGE AXIS
SETS UP ACROSS CENTRAL FLORIDA FROM EAST TO WEST. TEMPERATURES ARE
FORECAST TO REMAIN AROUND 5 TO 10 DEG WARMER THAN AVERAGE EACH DAY.
FOG WILL BECOME A POSSIBILITY THROUGH THE OVERNIGHT PERIOD TONIGHT
THROUGH SATURDAY MORNING DUE TO THE EXPECTED CLEARING...NEAR CALM
WINDS AND LOW-LEVEL MOISTURE. THE NAM12 CONDENSATION PRESSURE
DEFICITS REFLECT THIS AND ARE QUITE LOW ACROSS MUCH OF THE INTERIOR
AREAS TONIGHT INTO SATURDAY MORNING. THE SREF PROBABILITY OF VSBYS
DROPPING BELOW 1 MILE RANGE FROM 60-90%.
.LONG TERM (SUNDAY NIGHT-THURSDAY)...
THE EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT AND INDICATES
DRIER AND WARMER CONDITIONS ASSOCIATED WITH A DEEP LAYER RIDGE OVER
THE STATE. TEMPERATURES ARE FORECAST TO REMAIN ABOVE AVERAGE WITH
HIGHS FORECAST TO REACH THE LOW TO MID 80S EACH DAY AND LOWS
FORECAST TO REACH THE LOW 60S EACH NIGHT ACROSS THE INTERIOR
LOCATIONS (LOW 70S FOR COASTAL/METRO LOCATIONS). GFS ENSEMBLE
MEAN/GFS/ECMWF ARE INDICATING A COLD FRONT MOVING INTO THE REGION BY
THE END OF THE PERIOD AND STALLING NORTH OF OUR AREA.
&&
.MARINE...
A DRYING TREND IS EXPECTED THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK AS A FRONTAL BOUNDARY LIFTS NORTH AND HIGH PRESSURE BUILDS BACK
ACROSS THE MARINE AREA. WINDS AND SEAS WILL REMAIN BELOW
CAUTIONARY/ADVISORY LEVELS THROUGH THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 69 83 69 / 40 20 10 10
FORT LAUDERDALE 81 71 82 73 / 40 20 10 10
MIAMI 82 71 83 72 / 40 20 10 10
NAPLES 79 66 84 66 / 40 20 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
255 PM CST FRI JAN 31 2014
.DISCUSSION...
1046 AM CST
THE NEW 12 UTC GUIDANCE SUGGESTS THAT THE TRANSITION ZONE BETWEEN
ALL SNOW AND A MIX WILL BECOME ORIENTED ALONG A LINE FROM NEAR
STREATOR EAST-NORTHEASTWARD ACROSS THE SOUTHERN SUBURBS OF CHICAGO.
THIS WILL MAKE THINGS TRICKY IN TERMS OF TOTAL SNOWFALL AMOUNTS
ACROSS THE SOUTHERN SECTIONS OF THE METRO CHICAGO AREA...AS IT IS
POSSIBLE FOR SOME SLEET OR FREEZING RAIN AT TIMES...ESPECIALLY
DURING THE MORNING ON SATURDAY.
OVERALL...IT APPEARS THAT A HEAVY BAND OF SNOW WILL SET UP ACROSS
NORTHERN ILLINOIS...FROM JUST NORTH OF THE TRANSITION LINE...TROUGH
THE NORTHERN SUBURBS OF CHICAGO. A QUICK LOOK AT MODEL DERIVED CROSS
SECTIONS INDICATE FAVORABLE CONDITIONS FOR HEAVY SNOW. THE MOST
NOTABLE IS THE STRONG BAND OF MID LEVEL FRONTOGENESIS WITHIN
PROXIMITY TO A DECENT LAYER OF NEGATIVE EPV. SIMILARLY...MODEL
SOUNDINGS SHOW VERY STEEP MID LEVEL LAPSE RATES THROUGH THE
DGZ...WITH EVEN A LITTLE CAPE NOTED FOR PARCELS LIFTED ABOVE 650 MB.
GIVEN THE STRONG FORCING FOR ASCENT WITHIN THE BAND OF STRONG
FGEN...WE COULD SEE SOME SNOW RATES AROUND AN INCH PER HOUR FOR AT
LEAST A COUPLE HOURS SATURDAY MORNING AND PERHAPS SOME LIGHTNING
AS WELL. ADDITIONALLY...THE LIKELIHOOD OF A NEARLY ISOTHERMAL
LAYER BETWEEN THE SURFACE AND 700 MB AROUND 0 TO -4 DEGREES
CELSIUS...SUGGESTS THE GOOD POSSIBILITY OF GOOD AGGREGATION OF
SNOW FLAKES...WHICH WOULD ALSO SUPPORT HEAVY SNOW. ALL IN ALL...WE
HAVE DECIDED TO UPGRADE ALL OF NORTHERN ILLINOIS...BASICALLY ALONG
AND NORTH OF I-80 TO A WINTER STORM WARNING FOR MAINLY HEAVY SNOW.
THE HEAVIEST SNOW AREAS COULD RUN IN THE 6-10 INCH RANGE BY
SATURDAY AFTERNOON. HOWEVER...A WINTER MIX IS POSSIBLE ALONG THE
I-80 CORRIDOR ON SATURDAY MORNING...SO AMOUNTS COULD BE TAMPERED
SOME THERE. THE ONLY EXCEPTION TO THE WARING UPGRADE IS ACROSS
WINNEBAGO AND BOONE COUNTIES ACROSS NORTH CENTRAL ILLINOIS...WHERE
AMOUNTS MAY REMAIN JUST UNDER 6 INCHES. FOR THESE TWO COUNTIES WE
WILL GO TO AN ADVISORY.
SOUTH OF INTERSTATE 80...THE POTENTIAL FOR SIGNIFICANT ICING IN
EXCESS OF 0.25" IN ADDITION TO SNOW WILL RESULT IN AN UPGRADE TO A
WINTER STORM WARNING FOR LIVINGSTON...KANKAKEE COUNTIES IN
ILLINOIS AND LAKE AND PORTER COUNTIES IN INDIANA. SOUTH OF THESE
COUNTIES...THERE IS UNCERTAINTIES ON HOW LONG SURFACE TEMPERATURES
WILL REMAIN BELOW FREEZING. THERE IS A DECENT POTENTIAL THAT BY
THE TIME THE HEAVIEST PRECIP BEGINS SATURDAY MORNING THESE AREAS
COULD BE ABOVE FREEZING...THUS LIMITING THE ICE ACCUMULATIONS.
HOWEVER...THERE IS STILL THE POTENTIAL TO HAVE SOME DECENT ICE
ACCUMULATIONS AND SOME SNOW TONIGHT. THEREFORE...WE CHOSE TO LEAVE
THESE AREAS IN THE WINTER STORM WATCH...AND WE WILL REASSESS THESE
AREAS THIS AFTERNOON.
KJB
//PREV DISCUSSION...
342 AM CST
THIS MORNING...
THE PATTERN CHANGE CONTINUES TO UNFOLD...WITH THE FOCUS TURNING AWAY
FROM THE PARADE OF CLIPPER SYSTEMS TO MORE CLASSIC-STYLE WINTER
SYSTEMS. THE MORNING WILL START WITH CONSIDERABLE CLOUD COVER ACROSS
THE REGION...AND A BAROCLINIC ZONE STRETCHED ACROSS SOUTHERN
IA/NORTHERN MO INTO CENTRAL IL/IN. TEMPS TO THE NORTH ARE IN THE
TEENS/LOW 20S AND SOUTH MUCH WARMER AIR WAS PRESENT WITH SFC OBS IN
THE LOW 30S. IR IMAGERY INDICATES SOME COOLING WITH CLOUDS EARLY
THIS MORNING OVER NORTHERN IL...HOWEVER IT DOES NOT CURRENTLY APPEAR
TO BE SUGGESTIVE OF ANY PRECIP BEFORE 12Z.
SFC ANTI-CYCLONIC FEATURE WAS CENTERED OVER SOUTH DAKOTA/WESTERN
IOWA...AND HI-RES GUIDANCE CONTINUES TO SLIDE THIS FEATURE EAST
ACROSS THE UPPER MIDWEST/WESTERN GREAT LAKES THIS AFTERNOON. THIS
WILL AID IN SHARPENING UP THE BAROCLINIC ZONE AS WINDS ACROSS
NORTHERN IL BECOME NORTHERLY AND BY TONIGHT TURN NORTHEASTERLY. THIS
SHOULD HELP TO MAINTAIN A DRY WEDGE THROUGH THE AFTN FOR MOST AREAS
NORTH OF A LASALLE TO KANKAKEE LINE.
GUIDANCE HAS INDICATED A SLOWER DEPARTURE TO THE SFC RIDGE TO THE
NORTH OF THE FORECAST AREA...WHICH WOULD LIKELY TRANSLATE INTO A
SLOWER/STRONGER EVOLUTION TO THE DEVELOPING LOW PRESSURE. SINCE THE
SYSTEM HAS SOME PACIFIC ORIGINS...THE QPF ASSOCIATED OVERNIGHT INTO
SATURDAY WILL LIKELY BE REFLECTED WITH HIGHER VALUES. MODELS OF LATE
HAVE STRUGGLED WITH MAX TEMPS...AND TODAY IS A CHALLENGE WITH HIGHS
GIVEN THE EXPECTED NORTHERLY SFC FLOW. THAT BEING SAID...FEEL TEMPS
MAY STILL BE ABLE TO PUSH INTO THE UPPR TEENS ACROSS THE NORTHWEST
CWFA...LOW 20S NORTH OF I-80...AND NEARING MID 20S SOUTH OF A
PONTIAC TO KANKAKEE LINE.
HAVE DELAYED THE ONSET OF PRECIP FOR THIS MORNING...GIVEN THE
AFOREMENTIONED SLOWER DEVELOPMENT. EXPECT LIGHT SNOW TO STEADILY
DEVELOP AND OVERSPREAD THE FORECAST AREA BY MID/LATE AFTN...WITH
JUST MINOR SNOWFALL ACCUMULATIONS THROUGH MID-EVENING. AT THIS TIME
ANTICIPATE LESS THAN 1" NORTH OF I-80 AND TO THE SOUTH BETWEEN 1-2"
THROUGH LATE AFTN. MODEL SOUNDINGS ALL DEMONSTRATE COLD ENOUGH TEMPS
IN THE LLVLS TO SUPPORT SNOW THROUGH AFTN...WITH THE BAROCLINIC ZONE
SHARPENING BUT REMAINING SOUTH OF THE FORECAST AREA UNTIL LATER
TONIGHT.
CONFIDENCE...HIGH.
TONIGHT...
SFC RIDGE WILL GRADUALLY DRIFT EAST/NORTHEAST ACROSS LOWER MICHIGAN
TONIGHT...AS THE 500MB TROUGH AXIS PUSHES INTO THE SOUTHERN PLAINS.
GUIDANCE HAS A LOBE OF VORTICITY ROUNDING THE AXIS AND DEVELOPING A
SFC LOW OVER THE OZARKS LATE TONIGHT. WITH THE SLOWER EVOLUTION
PROCESS...AND PLACEMENT OF THE BAROCLINIC ZONE REMAINING WELL SOUTH
OF THE FORECAST AREA THROUGH 6-9Z SAT...EXPECT ALL PRECIP OVER THE
FORECAST AREA TO REMAIN AS SNOW. SOUNDINGS ALL SUPPORT
THIS...HOWEVER SOME WARMING IS NOTED IN PROFILES NEAR PNT/IKK/LAF.
TEMPS TONIGHT SHOULD REMAIN ELEVATED...GIVEN THE ABUNDANCE OF CLOUD
COVER AND INCREASING MOISTURE IN THE MID/UPR LEVELS. SO HAVE TEMPS
REMAINING NEAR STEADY FOR MUCH OF THE AREA...PERHAPS JUST FALLING A
FEW DEGREES.
THEN AFT 9Z IT APPEARS THE BAROCLINIC ZONE WILL BE OVER THE
SOUTHEAST CWFA...ALLOWING SOME FREEZING RAIN TO MIX INTO THE SNOW.
IN ADDITION SOME BETTER FORCING DOES TAKE SHAPE SOUTH OF
I-88...WHICH WILL LIKELY PROVIDE SOME ENHANCEMENT TO THE SNOWFALL
TOTALS. COULD SEE A BRIEF BURST OF UP TO 1"/HR SNOWFALL RATES.
CONFIDENCE...MEDIUM.
SATURDAY...
FURTHER NORTH TREND CONTINUES TO BE DEMONSTRATED AMONGST THE
GUIDANCE MEMBERS. HI-RES LOCAL WRF HAS THE SFC LOW ARRIVING OVER
CENTRAL IL JUST AFT DAYBREAK SAT...WITH THE 850MB LOW WELL NORTHWEST
ACROSS NORTHERN LASALLE TO CRYSTAL LAKE. IF THIS FURTHER NORTH PATH
VERIFIES...THE AXIS OF BETTER SNOWFALL WOULD LIKELY BE DISPLACED
NORTH FROM ITS CURRENT PATH...AND SETUP FROM LEE/OGLE COUNTIES
STRETCHING NORTHEAST THROUGH LAKE/NORTHERN COOK COUNTIES IN
ILLINOIS...WITH SNOWFALL TOTALS ARND 6-8". SOUTH OF THIS AXIS TEMPS
APPEARS TO BE SLIGHTLY WARMER AS A RESULT...AND THUS HAVE EXPANDED
THE COVERAGE OF FREEZING RAIN TO ACCOUNT FOR THIS SCENARIO. COULD
SEE IN EXTREME SOUTHEAST CWFA A PERIOD OF PLAIN RAIN SAT LATE
MORNING...HOWEVER GIVEN FROZEN SUB-SFC CONDS...ANY LIQUID WOULD
LIKELY FREEZE ON IMPACT. ICE ACCUMULATIONS APPEAR TO BE
CONSISTENT...WITH AROUND ONE QUARTER INCH POSSIBLE SAT IN THE
FAVORED SOUTHEAST AREAS.
BY EARLY AFTN THE SURGE OF WARMER AIR MAY EXTEND FROM LASALLE TO
GARY AND POINTS SOUTHEAST. THE BETTER FORCING APPEARS TO REMAIN JUST
NORTHWEST OF THIS LINE...AND WILL LIKELY RESULT IN SOME ADDITIONAL
ACCUMULATIONS THROUGH SAT AFTN. THEN HIGH PRESSURE PUSHES INTO THE
NORTHERN PLAINS AND SHOULD AID IN EJECTING THE WINTER STORM TO THE
EAST WITH COOLER AIR FILTERING BACK INTO THE REGION FOR SAT EVENING.
ANY LINGERING PRECIP BY LATE SAT AFTN SHOULD SWITCH BACK TO LIGHT
SNOW.
OPTED TO HOLD ONTO THE CURRENT WINTER STORM WATCH A LITTLE LONGER.
CONFIDENCE IS GROWING THAT THE FAR SOUTHEAST WILL BE LOOKING AT ICE
ACCUMULATIONS OF ARND 0.2 TO 0.3 INCHES. WITH THE NORTHWARD TREND IN
SOLUTIONS...THIS COULD RESULT IN NEEDING THE WARNING FURTHER
NORTH...AND COULD ALSO RESULT IN SOME PORTIONS OF THE WATCH GOING TO
AN ADVISORY. SO WITH THE LOWER CONFIDENCE...HAVE OPTED TO HOLD ONTO
THE WATCH A LITTLE LONGER AND ALLOW THE DAY SHIFT TO MAKE SOME
FURTHER ASSESSMENT.
TEMPS SAT WILL RANGE FROM THE LOW/MID 20S ACROSS THE NORTHWEST
CWFA...TO NEAR 30 FOR THE CENTRAL AREAS...AND LOW/MID 30S FOR
SOUTHEAST CWFA.
CONFIDENCE...MEDIUM.
BEACHLER
SUNDAY THROUGH MONDAY...
SURFACE HIGH PRESSURE BUILDS INTO THE MID/UPPER MISSISSIPPI VALLEY
LATE IN THE WEEKEND WITH CONFLUENT FLOW ALOFT BROAD SCALE
SUBSIDENCE. THIS WILL RESULT IN QUIET ALBEIT COLD WEATHER THIS
PERIOD. H85 TEMPS BOTTOM OUT AROUND -12C SUNDAY...THEN WARM
ADVECTION BEGINS TO TAKE HOLD LATE MONDAY AS THE RIDGE AXIS SHIFTS
TO OUR EAST. GUIDANCE IS IN PRETTY GOOD AGREEMENT WITH TEMPERATURES
DROPPING BELOW ZERO MONDAY MORNING UNDER A DECENT RADIATIONAL
COOLING SETUP. DAYTIME HIGHS ARE EXPECTED TO RISE INTO THE TEENS.
TUESDAY...
UPPER LOW CURRENTLY IN THE NORTH PAC SOUTH OF ALASKA IS PROGGED TO
DIG ACROSS SOCAL/BAJA EARLY MONDAY...THEN INTO THE SOUTHERN PLAINS
BY EARLY TUESDAY. IN RESPONSE...SURFACE LOW IS PROGGED TO DEEPEN AND
LIFT FROM TEXAS ACROSS THE OHIO VALLEY TUESDAY NIGHT INTO EARLY
WEDNESDAY. A WIDE OPEN GULF AHEAD OF THE LOW WILL RESULT IN STRONG
MOISTURE TRANSPORT INTO THE OHIO VALLEY WHERE GEFS INDICATES AROUND
3 STANDARD DEVIATION PWATS...BUT THIS HIGH MOISTURE STAYS WELL SOUTH
OF THE FORECAST AREA AND THE LOW TRACK IN GENERAL IS NOT OVERLY
FAVORABLE FOR SEEING HEAVY SNOW INTO NORTHERN ILLINOIS. BROAD AND
NOT PARTICULARLY STRONG MIDLEVEL ISENTROPIC ASCENT DEVELOPS AHEAD OF
THE LOW DURING THE DAY TUESDAY AND WILL HELP TO SATURATE THE
COLUMN...HOWEVER SUSPECT THAT GUIDANCE IS OVERDOING MOISTURE IN THE
DRY LOW LEVEL NORTHEASTERLY FLOW AND THE RESULTING QPF...WHICH FALLS
WELL NORTH OF THE H85 BAROCLINIC ZONE. STRONG Q-VECTOR CONVERGENCE
IS NOTED MOVING OVERHEAD LATE IN THE EVENING AND MIGHT BE THE BEST
CHANCE FOR ACCUMULATING SNOW TO DEVELOP...HOWEVER THE UPPER WAVE
COMES IN POSITIVELY TILTED WHICH IS NOT FAVORABLE FOR STRONG DPVA.
CONCEPTUALLY...SEEMS THAT GUIDANCE IS CURRENTLY OVERDOING THE LOCAL
PRECIP AMOUNTS. STILL A WAYS OUT THOUGH AND AM CONCERNED THAT THE
LOW TRACKS FARTHER NORTH THAN CURRENTLY ADVERTISED WHICH MAY THEN
LEAD TO HEAVIER SNOW AMOUNTS...THOUGH THIS SEEMS MORE OFTEN TO BE
THE CASE WITH NEGATIVELY TILTED TROUGHS.
WEDNESDAY THROUGH THURSDAY...
ANOTHER STRONG AND COLD HIGH IS PROGGED TO BUILD ACROSS THE REGION
FROM MIDWEEK ON WITH WELL BELOW NORMAL TEMPERATURE EXPECTED. SHOULD
BE DRY THOUGH WITH STRONG SUBSIDENCE IN PLACE AS MID/UPPER LEVEL
RIDGING TRIES TO BUILD IN PER GFS/GEFS.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* BRIEF PERIOD OF BKN MVFR CIG ABOVE 1500 FT THIS AFTERNOON.
* SNOW DEVELOPING EARLY-MID-EVENING...INCREASING IN INTENSITY
OVERNIGHT AND SATURDAY MORNING.
* IFR VIS/CIG DEVELOPING OVERNIGHT AND PERSISTING THROUGH SATURDAY
AFTERNOON...WITH A PERIOD LIFR/VLIFR POSSIBLE IN HEAVY SNOW
ROUGHLY 10Z-16/17Z.
* LOW CHANCE OF A PERIOD OF SLEET AT MDW SAT MORNING...MORE LIKELY
FARTHER SOUTH AT GYY.
* LIGHT/VARIABLE WINDS THIS AFTERNOON BECOMING NORTHEAST BY THIS
EVENING BUT LIKELY AT/UNDER 10 KT UNTIL SATURDAY MORNING. WINDS
EVENTUALLY SHIFTING NORTH-NORTHWEST SATURDAY AFTERNOON WITH SOME
GUSTS 15-20 KT LATER IN THE DAY.
RATZER
//DISCUSSION...UPDATED 18Z...
SERIES OF MID-LEVEL DISTURBANCES WILL RIPPLE ALONG FRONTAL ZONE
WHICH STRETCHES SOUTH OF THE TERMINALS FROM THE PLAINS TO THE
EASTERN GREAT LAKES. LIGHT SNOW OCCURRING ALONG THIS ZONE THIS
AFTERNOON MAY DRIFT NORTH SLOWLY...BUT IS EXPECTED TO WEAKEN AS IT
DOES WITH A RELATIVELY LOW THREAT OF REACHING THE TERMINALS BEFORE
NIGHTFALL. SNOW DOES LOOK TO DEVELOP BY MID-EVENING AS A SLIGHTLY
STRONGER DISTURBANCE APPROACHES THIS EVENING...WITH SNOW
PERSISTING AND INCREASING IN INTENSITY LATE TONIGHT AND SATURDAY
MORNING AS MORE AMPLIFIED UPPER TROUGH AND SURFACE LOW MOVE ACROSS
THE REGION. THE STRONGEST/MOST PERSISTENT FORCING FOR ASCENT AND
PRECIP PRODUCTION SHOULD BE GENERALLY 10Z-18Z OR SO...WITH A
PERIOD SATURDAY MORNING WITH A RELATIVELY HIGH LIKELIHOOD OF
LIFR/VLIFR CONDITIONS IN MODERATE/HEAVY SNOWFALL...ESPECIALLY
ALONG A SWATH FROM KVYS TO THE CHICAGO METRO TERMINALS. RFD TO THE
NORTH HAS A LOWER VLIFR POTENTIAL...WHILE GYY MAY SEE SNOW CHANGE
TO A SLEET/FREEZING RAIN/SNOW MIX FOR A TIME MID/LATE SATURDAY
MORNING. VIS AS LOW AS 1/4SM-1/2SM AND CIGS AROUND 500 FT POSSIBLE
DURING HEAVIEST SNOW SATURDAY MORNING. SNOW INTENSITY THEN
EXPECTED TO GRADUALLY DIMINISH SATURDAY AFTERNOON...AS FORCING
WEAKENS.
WEAK HIGH PRESSURE RIDGE ACROSS THE REGION THIS AFTERNOON IN
ADVANCE OF SATURDAYS STORM SYSTEM WILL RESULT IN LIGHT/VARIABLE
WINDS LESS THAN 10 KT THROUGH THIS AFTERNOON. WINDS WILL
EVENTUALLY SHIFT NORTHEAST AT/BELOW 10 KT THIS EVENING AS THE
SURFACE WAVE BEGINS TO TAKE SHAPE OVER THE SOUTHERN PLAINS AND
LIFT TOWARD THE REGION. WINDS WILL THEN VEER MORE NORTH-NORTHWEST
SATURDAY AFTERNOON AS THE SURFACE LOW PASSES SOUTH OF THE
TERMINALS...BECOMING STRONGER WITH SOME GUSTS 15-20 KT POSSIBLE IN
THE AFTERNOON.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN PRECIP ONSET TIME. MDW LIKELY TO BE 1-2 HRS
EARLIER THAN ORD.
* HIGH CONFIDENCE IN IFR CONDITIONS AND LOWEST CIG/VIS AND BEST
ACCUMULATION WILL BE MAINLY BETWEEN 09Z-17Z SATURDAY MORNING.
MEDIUM-HIGH CONFIDENCE IN LIFR/VLIFR OCCURRING.
* LOW CONFIDENCE IN SLEET OCCURRING AS FAR NORTH AS MDW/ORD.
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS/SPEEDS THROUGH PERIOD.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...POSSIBLY SOME FLURRIES EARLY. MVFR IMPROVING
THROUGH THE EVE.
SUNDAY-MONDAY...VFR LIKELY.
TUESDAY-TUESDAY NIGHT...SNOW LIKELY DURING A PERIOD IN THIS TIME.
WEDNESDAY...SMALL CHANCE OF SNOW.
THURSDAY...VFR LIKELY.
MTF
&&
.MARINE...
255 PM CST
HIGH PRESSURE CENTERED OVER EASTERN IOWA WILL MOVE ACROSS LAKE
MICHIGAN THIS EVENING AND THEN MERGE WITH ANOTHER AREA OF HIGH
PRESSURE OVER THE MID ATLANTIC REGION. WITH HIGH PRESSURE THE
DOMINANT FEATURE OVER THE REGION...WINDS AND WAVES WILL BE MUCH
CALMER THAN WHAT HAS BEEN OBSERVED THROUGH MUCH OF THE PAST
SEVERAL WEEK. ALSO...EXTENSIVE BROKEN ICE COVER OVER THE FAR
SOUTH END OF THE LAKE WILL KEEP WAVES NEARLY CALM WHILE SOLID ICE
OVER THE NORTH END OF THE LAKE WILL ELIMINATE ANY WAVE ACTION.
MUCH OF THE OPEN WATERS THROUGH THE MIDDLE OF THE LAKE WILL STILL
SEE WAVE ACTION AND INCREASE TO 5 TO 8 FT AS MODERATE...GENERALLY
NORTHWEST TO WEST WINDS PREVAIL FROM SATURDAY NIGHT THROUGH EARLY
NEXT WEEK. AS DEEPENING LOW PRESSURE TRACKS THROUGH THE OHIO
VALLEY AND STRONG HIGH PRESSURE BUILDS ACROSS THE NORTHERN AND
CENTRAL PLAINS...STRENGTHENING NORTH WINDS WILL DEVELOP...POSSIBLY
APPROACHING GALE FORCE BY WEDNESDAY OR THURSDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-ILZ012-
ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-ILZ032...9
PM FRIDAY TO 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ003-ILZ004...9 PM FRIDAY TO 6 PM
SATURDAY.
WINTER WEATHER ADVISORY...ILZ033-ILZ039 UNTIL 6 PM SATURDAY.
IN...WINTER STORM WARNING...INZ001-INZ002...9 PM FRIDAY TO 6 PM
SATURDAY.
WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 PM
SATURDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
231 PM CST Fri Jan 31 2014
.DISCUSSION...
ISSUED 215 PM CST Fri Jan 31 2014
Band of light snow extending west through east over about the
northern one half of the forecast area associated with persistent
isentropic lift noted on the 290k surface early this afternoon.
With time, the band will shift slowly north and east while the
weather system taking shape over the southern plains moves into
eastern OK by late tonight. Accumulations with this band of snow
from this morning into early this afternoon have been in the 1 to
locally 2 inch range.
SHORT TERM...Tonight through Monday
Significant snow and ice over parts of central and west central
Illinois late tonight into Saturday the main forecast challenge
during this period. A Winter Storm Warning will be in effect from
late this evening through Saturday for areas roughly along and
west of a Jacksonville to Lincoln to Bloomington line. Further
to the south and east will add an advisory for late this evening
through the noon hour of Saturday for the threat of a wintry mix
which will change to rain by afternoon.
Models this period in decent agreement with the surface boundary
expected to make a trip north tonight into Saturday morning. The
GFS appears to be too fast with the NAM, ECMWF and SREF all clustered
over parts of east central Illinois. The northward trend continues
from previous model runs resulting in a north and west adjustment
to the freezing rain area late tonight and especially during the
morning hours of Saturday. Still appears that around a quarter of
an inch of ice will be possible from Jacksonville to Lincoln to
near Bloomington. Further to the northwest, the threat for heavy
snow continues, especially north and west of Peoria where 6 to 8
inches of snow will accumulate by late Saturday afternoon. Further
to the southeast, it appears enough warm air will advect north
into south central and southeast Illinois to change any wintry mix
to rain Saturday morning with afternoon tempertures along and
south of I70 closing in on 50 degrees! If the low should continue
its north and west adjustment in future runs, we will have to shift
the threat for significant ice and snow further northwest as well.
One parameter models have been rather consistent on is the depiction
of a coupled jet structure at 300 mb tomorrow morning into the early
afternoon hours which would enhance the lift over west central and
central illinois with a corresponding increase in precip rates. 4km
hi res model radar simulations seem to pick up on this later tomorrow
morning into the afternoon hours with a more "convective" look to
the banded precip as it tracks quickly to the northeast early in
the afternoon. Models suggest lingering rain and snow in the east
and southeast tomorrow evening as the upper wave shifts away from
the area. Not liking what the lastest ECMWF is depicting as it keeps
the frontal boundary further west with additional wave development
along the front with precip holding thru the night in southeast IL.
Will have to see if other models follow its solution for later Sat.
night. If they do, we will need to keep precip going longer across
far east central and southeast Illinois into Sunday morning. But for
now, since this was not showing up on previous runs, will side more
with the progressive GFS solution in taking the precip to the east
of our forecast area by late Saturday evening.
Colder weather settles in for the remainder of the period as another
Polar high shifts southeast into the region. Temperatures more of
a challenge later in the weekend, especially if we have a decent snow
cover across the area. Tried to go at or below most of the
guidance during this period with the coldest morning temperatures
late Sunday night into Monday when the high is positioned right
over our area.
LONG TERM...Tuesday through Friday
Major storm system expected to affect parts of the area Tuesday into
Tuesday night...followed by another very cold air mass for the end
of the week.
Next system is expected to move out of the Southern Plains and into
the Tennessee Valley Tuesday and Tuesday night. Thermal profiles
suggest that precipitation should be mostly snow. There remains
some substantial spread in the solutions, but it is looking like
significant amounts of snow may be possible over a portion of central
or southeast Illinois. Run to run consistency has been poor and
the forecast will be honed as Tuesday approaches. Cold air will
advect in behind the system with overnight lows around zero or lower
north of U.S. Highway 36 Thursday and Friday mornings.
Short Term...Smith
Long Term....Barker
&&
.AVIATION...
ISSUED 1102 AM CST Fri Jan 31 2014
Latest NAM and HRRR continue to indicate weak disturbances
enhancing general area of lift over forecast area. They both
suggest a lull this afternoon prior to next wave bringing in
precip this evening. Another lull after 06z is suggected before
main event on Saturday. Models have trended warmer and suggest
that a variety of precip types will be possible. Will generally
follow precip type suggested by NAM, but with a slightly warmer
scenario given the model trends.
Will keep generally MVFR with occasional IFR Cigs today and then
keep IFR conditions in place beginning this evening with the next
wave of precip.
Wind direction will depend on how far north front pushes ahead of
the Saturday`s sfc system which remains in flux. However, speeds
should be on the low side.
Barker
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING from 9 PM this evening to 6 PM CST Saturday
FOR ILZ027>031-036>038-040>043-047>050.
WINTER WEATHER ADVISORY from 9 PM this evening to Noon CST
Saturday FOR ILZ044>046-051>057-061.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1153 AM CST FRI JAN 31 2014
.DISCUSSION...
1046 AM CST
THE NEW 12 UTC GUIDANCE SUGGESTS THAT THE TRANSITION ZONE BETWEEN
ALL SNOW AND A MIX WILL BECOME ORIENTED ALONG A LINE FROM NEAR
STREATOR EAST-NORTHEASTWARD ACROSS THE SOUTHERN SUBURBS OF CHICAGO.
THIS WILL MAKE THINGS TRICKY IN TERMS OF TOTAL SNOWFALL AMOUNTS
ACROSS THE SOUTHERN SECTIONS OF THE METRO CHICAGO AREA...AS IT IS
POSSIBLE FOR SOME SLEET OR FREEZING RAIN AT TIMES...ESPECIALLY
DURING THE MORNING ON SATURDAY.
OVERALL...IT APPEARS THAT A HEAVY BAND OF SNOW WILL SET UP ACROSS
NORTHERN ILLINOIS...FROM JUST NORTH OF THE TRANSITION LINE...TROUGH
THE NORTHERN SUBURBS OF CHICAGO. A QUICK LOOK AT MODEL DERIVED CROSS
SECTIONS INDICATE FAVORABLE CONDITIONS FOR HEAVY SNOW. THE MOST
NOTABLE IS THE STRONG BAND OF MID LEVEL FRONTOGENESIS WITHIN
PROXIMITY TO A DECENT LAYER OF NEGATIVE EPV. SIMILARLY...MODEL
SOUNDINGS SHOW VERY STEEP MID LEVEL LAPSE RATES THROUGH THE
DGZ...WITH EVEN A LITTLE CAPE NOTED FOR PARCELS LIFTED ABOVE 650 MB.
GIVEN THE STRONG FORCING FOR ASCENT WITHIN THE BAND OF STRONG
FGEN...WE COULD SEE SOME SNOW RATES AROUND AN INCH PER HOUR FOR AT
LEAST A COUPLE HOURS SATURDAY MORNING AND PERHAPS SOME LIGHTNING
AS WELL. ADDITIONALLY...THE LIKELIHOOD OF A NEARLY ISOTHERMAL
LAYER BETWEEN THE SURFACE AND 700 MB AROUND 0 TO -4 DEGREES
CELSIUS...SUGGESTS THE GOOD POSSIBILITY OF GOOD AGGREGATION OF
SNOW FLAKES...WHICH WOULD ALSO SUPPORT HEAVY SNOW. ALL IN ALL...WE
HAVE DECIDED TO UPGRADE ALL OF NORTHERN ILLINOIS...BASICALLY ALONG
AND NORTH OF I-80 TO A WINTER STORM WARNING FOR MAINLY HEAVY SNOW.
THE HEAVIEST SNOW AREAS COULD RUN IN THE 6-10 INCH RANGE BY
SATURDAY AFTERNOON. HOWEVER...A WINTER MIX IS POSSIBLE ALONG THE
I-80 CORRIDOR ON SATURDAY MORNING...SO AMOUNTS COULD BE TAMPERED
SOME THERE. THE ONLY EXCEPTION TO THE WARING UPGRADE IS ACROSS
WINNEBAGO AND BOONE COUNTIES ACROSS NORTH CENTRAL ILLINOIS...WHERE
AMOUNTS MAY REMAIN JUST UNDER 6 INCHES. FOR THESE TWO COUNTIES WE
WILL GO TO AN ADVISORY.
SOUTH OF INTERSTATE 80...THE POTENTIAL FOR SIGNIFICANT ICING IN
EXCESS OF 0.25" IN ADDITION TO SNOW WILL RESULT IN AN UPGRADE TO A
WINTER STORM WARNING FOR LIVINGSTON...KANKAKEE COUNTIES IN
ILLINOIS AND LAKE AND PORTER COUNTIES IN INDIANA. SOUTH OF THESE
COUNTIES...THERE IS UNCERTAINTIES ON HOW LONG SURFACE TEMPERATURES
WILL REMAIN BELOW FREEZING. THERE IS A DECENT POTENTIAL THAT BY
THE TIME THE HEAVIEST PRECIP BEGINS SATURDAY MORNING THESE AREAS
COULD BE ABOVE FREEZING...THUS LIMITING THE ICE ACCUMULATIONS.
HOWEVER...THERE IS STILL THE POTENTIAL TO HAVE SOME DECENT ICE
ACCUMULATIONS AND SOME SNOW TONIGHT. THEREFORE...WE CHOSE TO LEAVE
THESE AREAS IN THE WINTER STORM WATCH...AND WE WILL REASSESS THESE
AREAS THIS AFTERNOON.
KJB
//PREV DISCUSSION...
342 AM CST
THIS MORNING...
THE PATTERN CHANGE CONTINUES TO UNFOLD...WITH THE FOCUS TURNING AWAY
FROM THE PARADE OF CLIPPER SYSTEMS TO MORE CLASSIC-STYLE WINTER
SYSTEMS. THE MORNING WILL START WITH CONSIDERABLE CLOUD COVER ACROSS
THE REGION...AND A BAROCLINIC ZONE STRETCHED ACROSS SOUTHERN
IA/NORTHERN MO INTO CENTRAL IL/IN. TEMPS TO THE NORTH ARE IN THE
TEENS/LOW 20S AND SOUTH MUCH WARMER AIR WAS PRESENT WITH SFC OBS IN
THE LOW 30S. IR IMAGERY INDICATES SOME COOLING WITH CLOUDS EARLY
THIS MORNING OVER NORTHERN IL...HOWEVER IT DOES NOT CURRENTLY APPEAR
TO BE SUGGESTIVE OF ANY PRECIP BEFORE 12Z.
SFC ANTI-CYCLONIC FEATURE WAS CENTERED OVER SOUTH DAKOTA/WESTERN
IOWA...AND HI-RES GUIDANCE CONTINUES TO SLIDE THIS FEATURE EAST
ACROSS THE UPPER MIDWEST/WESTERN GREAT LAKES THIS AFTERNOON. THIS
WILL AID IN SHARPENING UP THE BAROCLINIC ZONE AS WINDS ACROSS
NORTHERN IL BECOME NORTHERLY AND BY TONIGHT TURN NORTHEASTERLY. THIS
SHOULD HELP TO MAINTAIN A DRY WEDGE THROUGH THE AFTN FOR MOST AREAS
NORTH OF A LASALLE TO KANKAKEE LINE.
GUIDANCE HAS INDICATED A SLOWER DEPARTURE TO THE SFC RIDGE TO THE
NORTH OF THE FORECAST AREA...WHICH WOULD LIKELY TRANSLATE INTO A
SLOWER/STRONGER EVOLUTION TO THE DEVELOPING LOW PRESSURE. SINCE THE
SYSTEM HAS SOME PACIFIC ORIGINS...THE QPF ASSOCIATED OVERNIGHT INTO
SATURDAY WILL LIKELY BE REFLECTED WITH HIGHER VALUES. MODELS OF LATE
HAVE STRUGGLED WITH MAX TEMPS...AND TODAY IS A CHALLENGE WITH HIGHS
GIVEN THE EXPECTED NORTHERLY SFC FLOW. THAT BEING SAID...FEEL TEMPS
MAY STILL BE ABLE TO PUSH INTO THE UPPR TEENS ACROSS THE NORTHWEST
CWFA...LOW 20S NORTH OF I-80...AND NEARING MID 20S SOUTH OF A
PONTIAC TO KANKAKEE LINE.
HAVE DELAYED THE ONSET OF PRECIP FOR THIS MORNING...GIVEN THE
AFOREMENTIONED SLOWER DEVELOPMENT. EXPECT LIGHT SNOW TO STEADILY
DEVELOP AND OVERSPREAD THE FORECAST AREA BY MID/LATE AFTN...WITH
JUST MINOR SNOWFALL ACCUMULATIONS THROUGH MID-EVENING. AT THIS TIME
ANTICIPATE LESS THAN 1" NORTH OF I-80 AND TO THE SOUTH BETWEEN 1-2"
THROUGH LATE AFTN. MODEL SOUNDINGS ALL DEMONSTRATE COLD ENOUGH TEMPS
IN THE LLVLS TO SUPPORT SNOW THROUGH AFTN...WITH THE BAROCLINIC ZONE
SHARPENING BUT REMAINING SOUTH OF THE FORECAST AREA UNTIL LATER
TONIGHT.
CONFIDENCE...HIGH.
TONIGHT...
SFC RIDGE WILL GRADUALLY DRIFT EAST/NORTHEAST ACROSS LOWER MICHIGAN
TONIGHT...AS THE 500MB TROUGH AXIS PUSHES INTO THE SOUTHERN PLAINS.
GUIDANCE HAS A LOBE OF VORTICITY ROUNDING THE AXIS AND DEVELOPING A
SFC LOW OVER THE OZARKS LATE TONIGHT. WITH THE SLOWER EVOLUTION
PROCESS...AND PLACEMENT OF THE BAROCLINIC ZONE REMAINING WELL SOUTH
OF THE FORECAST AREA THROUGH 6-9Z SAT...EXPECT ALL PRECIP OVER THE
FORECAST AREA TO REMAIN AS SNOW. SOUNDINGS ALL SUPPORT
THIS...HOWEVER SOME WARMING IS NOTED IN PROFILES NEAR PNT/IKK/LAF.
TEMPS TONIGHT SHOULD REMAIN ELEVATED...GIVEN THE ABUNDANCE OF CLOUD
COVER AND INCREASING MOISTURE IN THE MID/UPR LEVELS. SO HAVE TEMPS
REMAINING NEAR STEADY FOR MUCH OF THE AREA...PERHAPS JUST FALLING A
FEW DEGREES.
THEN AFT 9Z IT APPEARS THE BAROCLINIC ZONE WILL BE OVER THE
SOUTHEAST CWFA...ALLOWING SOME FREEZING RAIN TO MIX INTO THE SNOW.
IN ADDITION SOME BETTER FORCING DOES TAKE SHAPE SOUTH OF
I-88...WHICH WILL LIKELY PROVIDE SOME ENHANCEMENT TO THE SNOWFALL
TOTALS. COULD SEE A BRIEF BURST OF UP TO 1"/HR SNOWFALL RATES.
CONFIDENCE...MEDIUM.
SATURDAY...
FURTHER NORTH TREND CONTINUES TO BE DEMONSTRATED AMONGST THE
GUIDANCE MEMBERS. HI-RES LOCAL WRF HAS THE SFC LOW ARRIVING OVER
CENTRAL IL JUST AFT DAYBREAK SAT...WITH THE 850MB LOW WELL NORTHWEST
ACROSS NORTHERN LASALLE TO CRYSTAL LAKE. IF THIS FURTHER NORTH PATH
VERIFIES...THE AXIS OF BETTER SNOWFALL WOULD LIKELY BE DISPLACED
NORTH FROM ITS CURRENT PATH...AND SETUP FROM LEE/OGLE COUNTIES
STRETCHING NORTHEAST THROUGH LAKE/NORTHERN COOK COUNTIES IN
ILLINOIS...WITH SNOWFALL TOTALS ARND 6-8". SOUTH OF THIS AXIS TEMPS
APPEARS TO BE SLIGHTLY WARMER AS A RESULT...AND THUS HAVE EXPANDED
THE COVERAGE OF FREEZING RAIN TO ACCOUNT FOR THIS SCENARIO. COULD
SEE IN EXTREME SOUTHEAST CWFA A PERIOD OF PLAIN RAIN SAT LATE
MORNING...HOWEVER GIVEN FROZEN SUB-SFC CONDS...ANY LIQUID WOULD
LIKELY FREEZE ON IMPACT. ICE ACCUMULATIONS APPEAR TO BE
CONSISTENT...WITH AROUND ONE QUARTER INCH POSSIBLE SAT IN THE
FAVORED SOUTHEAST AREAS.
BY EARLY AFTN THE SURGE OF WARMER AIR MAY EXTEND FROM LASALLE TO
GARY AND POINTS SOUTHEAST. THE BETTER FORCING APPEARS TO REMAIN JUST
NORTHWEST OF THIS LINE...AND WILL LIKELY RESULT IN SOME ADDITIONAL
ACCUMULATIONS THROUGH SAT AFTN. THEN HIGH PRESSURE PUSHES INTO THE
NORTHERN PLAINS AND SHOULD AID IN EJECTING THE WINTER STORM TO THE
EAST WITH COOLER AIR FILTERING BACK INTO THE REGION FOR SAT EVENING.
ANY LINGERING PRECIP BY LATE SAT AFTN SHOULD SWITCH BACK TO LIGHT
SNOW.
OPTED TO HOLD ONTO THE CURRENT WINTER STORM WATCH A LITTLE LONGER.
CONFIDENCE IS GROWING THAT THE FAR SOUTHEAST WILL BE LOOKING AT ICE
ACCUMULATIONS OF ARND 0.2 TO 0.3 INCHES. WITH THE NORTHWARD TREND IN
SOLUTIONS...THIS COULD RESULT IN NEEDING THE WARNING FURTHER
NORTH...AND COULD ALSO RESULT IN SOME PORTIONS OF THE WATCH GOING TO
AN ADVISORY. SO WITH THE LOWER CONFIDENCE...HAVE OPTED TO HOLD ONTO
THE WATCH A LITTLE LONGER AND ALLOW THE DAY SHIFT TO MAKE SOME
FURTHER ASSESSMENT.
TEMPS SAT WILL RANGE FROM THE LOW/MID 20S ACROSS THE NORTHWEST
CWFA...TO NEAR 30 FOR THE CENTRAL AREAS...AND LOW/MID 30S FOR
SOUTHEAST CWFA.
CONFIDENCE...MEDIUM.
BEACHLER
SUNDAY THROUGH MONDAY...
SURFACE HIGH PRESSURE BUILDS INTO THE MID/UPPER MISSISSIPPI VALLEY
LATE IN THE WEEKEND WITH CONFLUENT FLOW ALOFT BROAD SCALE
SUBSIDENCE. THIS WILL RESULT IN QUIET ALBEIT COLD WEATHER THIS
PERIOD. H85 TEMPS BOTTOM OUT AROUND -12C SUNDAY...THEN WARM
ADVECTION BEGINS TO TAKE HOLD LATE MONDAY AS THE RIDGE AXIS SHIFTS
TO OUR EAST. GUIDANCE IS IN PRETTY GOOD AGREEMENT WITH TEMPERATURES
DROPPING BELOW ZERO MONDAY MORNING UNDER A DECENT RADIATIONAL
COOLING SETUP. DAYTIME HIGHS ARE EXPECTED TO RISE INTO THE TEENS.
TUESDAY...
UPPER LOW CURRENTLY IN THE NORTH PAC SOUTH OF ALASKA IS PROGGED TO
DIG ACROSS SOCAL/BAJA EARLY MONDAY...THEN INTO THE SOUTHERN PLAINS
BY EARLY TUESDAY. IN RESPONSE...SURFACE LOW IS PROGGED TO DEEPEN AND
LIFT FROM TEXAS ACROSS THE OHIO VALLEY TUESDAY NIGHT INTO EARLY
WEDNESDAY. A WIDE OPEN GULF AHEAD OF THE LOW WILL RESULT IN STRONG
MOISTURE TRANSPORT INTO THE OHIO VALLEY WHERE GEFS INDICATES AROUND
3 STANDARD DEVIATION PWATS...BUT THIS HIGH MOISTURE STAYS WELL SOUTH
OF THE FORECAST AREA AND THE LOW TRACK IN GENERAL IS NOT OVERLY
FAVORABLE FOR SEEING HEAVY SNOW INTO NORTHERN ILLINOIS. BROAD AND
NOT PARTICULARLY STRONG MIDLEVEL ISENTROPIC ASCENT DEVELOPS AHEAD OF
THE LOW DURING THE DAY TUESDAY AND WILL HELP TO SATURATE THE
COLUMN...HOWEVER SUSPECT THAT GUIDANCE IS OVERDOING MOISTURE IN THE
DRY LOW LEVEL NORTHEASTERLY FLOW AND THE RESULTING QPF...WHICH FALLS
WELL NORTH OF THE H85 BAROCLINIC ZONE. STRONG Q-VECTOR CONVERGENCE
IS NOTED MOVING OVERHEAD LATE IN THE EVENING AND MIGHT BE THE BEST
CHANCE FOR ACCUMULATING SNOW TO DEVELOP...HOWEVER THE UPPER WAVE
COMES IN POSITIVELY TILTED WHICH IS NOT FAVORABLE FOR STRONG DPVA.
CONCEPTUALLY...SEEMS THAT GUIDANCE IS CURRENTLY OVERDOING THE LOCAL
PRECIP AMOUNTS. STILL A WAYS OUT THOUGH AND AM CONCERNED THAT THE
LOW TRACKS FARTHER NORTH THAN CURRENTLY ADVERTISED WHICH MAY THEN
LEAD TO HEAVIER SNOW AMOUNTS...THOUGH THIS SEEMS MORE OFTEN TO BE
THE CASE WITH NEGATIVELY TILTED TROUGHS.
WEDNESDAY THROUGH THURSDAY...
ANOTHER STRONG AND COLD HIGH IS PROGGED TO BUILD ACROSS THE REGION
FROM MIDWEEK ON WITH WELL BELOW NORMAL TEMPERATURE EXPECTED. SHOULD
BE DRY THOUGH WITH STRONG SUBSIDENCE IN PLACE AS MID/UPPER LEVEL
RIDGING TRIES TO BUILD IN PER GFS/GEFS.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW DEVELOPING EARLY-MID-EVENING...INCREASING IN INTENSITY
OVERNIGHT AND SATURDAY MORNING.
* IFR VIS/CIG DEVELOPING OVERNIGHT AND PERSISTING THROUGH SATURDAY
AFTERNOON...WITH A PERIOD LIFR/VLIFR POSSIBLE IN HEAVY SNOW
ROUGHLY 10Z-16/17Z.
* LOW CHANCE OF A PERIOD OF SLEET AT MDW SAT MORNING...MORE LIKELY
FARTHER SOUTH AT GYY.
* LIGHT/VARIABLE WINDS THIS AFTERNOON BECOMING NORTHEAST BY THIS
EVENING BUT LIKELY AT/UNDER 10 KT UNTIL SATURDAY MORNING. WINDS
EVENTUALLY SHIFTING NORTH-NORTHWEST SATURDAY AFTERNOON WITH SOME
GUSTS 15-20 KT LATER IN THE DAY.
RATZER
//DISCUSSION...UPDATED 18Z...
SERIES OF MID-LEVEL DISTURBANCES WILL RIPPLE ALONG FRONTAL ZONE
WHICH STRETCHES SOUTH OF THE TERMINALS FROM THE PLAINS TO THE
EASTERN GREAT LAKES. LIGHT SNOW OCCURRING ALONG THIS ZONE THIS
AFTERNOON MAY DRIFT NORTH SLOWLY...BUT IS EXPECTED TO WEAKEN AS IT
DOES WITH A RELATIVELY LOW THREAT OF REACHING THE TERMINALS BEFORE
NIGHTFALL. SNOW DOES LOOK TO DEVELOP BY MID-EVENING AS A SLIGHTLY
STRONGER DISTURBANCE APPROACHES THIS EVENING...WITH SNOW
PERSISTING AND INCREASING IN INTENSITY LATE TONIGHT AND SATURDAY
MORNING AS MORE AMPLIFIED UPPER TROUGH AND SURFACE LOW MOVE ACROSS
THE REGION. THE STRONGEST/MOST PERSISTENT FORCING FOR ASCENT AND
PRECIP PRODUCTION SHOULD BE GENERALLY 10Z-18Z OR SO...WITH A
PERIOD SATURDAY MORNING WITH A RELATIVELY HIGH LIKELIHOOD OF
LIFR/VLIFR CONDITIONS IN MODERATE/HEAVY SNOWFALL...ESPECIALLY
ALONG A SWATH FROM KVYS TO THE CHICAGO METRO TERMINALS. RFD TO THE
NORTH HAS A LOWER VLIFR POTENTIAL...WHILE GYY MAY SEE SNOW CHANGE
TO A SLEET/FREEZING RAIN/SNOW MIX FOR A TIME MID/LATE SATURDAY
MORNING. VIS AS LOW AS 1/4SM-1/2SM AND CIGS AROUND 500 FT POSSIBLE
DURING HEAVIEST SNOW SATURDAY MORNING. SNOW INTENSITY THEN
EXPECTED TO GRADUALLY DIMINISH SATURDAY AFTERNOON...AS FORCING
WEAKENS.
WEAK HIGH PRESSURE RIDGE ACROSS THE REGION THIS AFTERNOON IN
ADVANCE OF SATURDAYS STORM SYSTEM WILL RESULT IN LIGHT/VARIABLE
WINDS LESS THAN 10 KT THROUGH THIS AFTERNOON. WINDS WILL
EVENTUALLY SHIFT NORTHEAST AT/BELOW 10 KT THIS EVENING AS THE
SURFACE WAVE BEGINS TO TAKE SHAPE OVER THE SOUTHERN PLAINS AND
LIFT TOWARD THE REGION. WINDS WILL THEN VEER MORE NORTH-NORTHWEST
SATURDAY AFTERNOON AS THE SURFACE LOW PASSES SOUTH OF THE
TERMINALS...BECOMING STRONGER WITH SOME GUSTS 15-20 KT POSSIBLE IN
THE AFTERNOON.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN PRECIP ONSET TIME. MDW LIKELY TO BE 1-2 HRS
EARLIER THAN ORD.
* HIGH CONFIDENCE IN IFR CONDITIONS AND LOWEST CIG/VIS AND BEST
ACCUMULATION WILL BE MAINLY BETWEEN 09Z-17Z SATURDAY MORNING.
MEDIUM-HIGH CONFIDENCE IN LIFR/VLIFR OCCURRING.
* LOW CONFIDENCE IN SLEET OCCURRING AS FAR NORTH AS MDW/ORD.
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS/SPEEDS THROUGH PERIOD.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...POSSIBLY SOME FLURRIES EARLY. MVFR IMPROVING
THROUGH THE EVE.
SUNDAY-MONDAY...VFR LIKELY.
TUESDAY-TUESDAY NIGHT...SNOW LIKELY DURING A PERIOD IN THIS TIME.
WEDNESDAY...SMALL CHANCE OF SNOW.
THURSDAY...VFR LIKELY.
MTF
&&
.MARINE...
208 AM CST
CONDITIONS WILL REMAIN SOMEWHAT QUIET OVER THE LAKE THROUGH THIS
EVENING...ESPECIALLY COMPARED TO MUCH OF THIS WINTER. HIGH PRESSURE
WILL MOVE ACROSS THE LAKE BY AFTERNOON EASING WIND SPEEDS. LOW
PRESSURE DEVELOPING NORTHEAST FROM THE OZARKS LATER TONIGHT WILL
MOVE TO THE EASTERN GREAT LAKES BY MIDDAY SATURDAY. THIS WILL
RESULT IN A TIGHTENED PRESSURE GRADIENT ON ITS BACKSIDE WHICH WILL
LEAD TO NORTHERLY WINDS INCREASING SATURDAY AFTERNOON AND EVENING.
WHILE CONDITIONS CURRENTLY ARE FORECAST TO REMAIN BELOW SMALL
CRAFT ADVISORY CRITERIA ALONG THE ILLINOIS AND INDIANA
SHORE...MUCH OF THE WAVE FORECAST IS BASED ON THE IDEA THAT QUITE
A LOT OF ICE STILL EXISTS OFFSHORE...RESULTING IN A DAMPENING OF
THE FULL FETCH DOWN THE LAKE. THIS MAY NOT BE THE CASE AND WOULD
LEAD TO HIGHER WAVES LIKELY MORE IN THE 4-7 FT AREA...NAMELY
ALONG THE INDIANA SHORE. BUT UNTIL A BETTER ESTIMATE CAN BE
MADE...NAMELY FROM SATELLITE /MEANING THE NEED FOR A CLEAR OR
MOSTLY CLEAR SKY/...WE WILL HAVE TO MAKE THE BEST FORECAST FROM THE
MOST RECENT ICE COVERAGE. LOOKING FURTHER AHEAD...THERE HAS BEEN
SIGNAL FOR SEVERAL DAYS OF A DEEPENING LOW MOVING FROM THE MID-
SOUTH TO NEW ENGLAND DURING THE TUESDAY NIGHT-WEDNESDAY TIME
FRAME...WHICH WOULD RESULT IN STRENGTHENING NORTH TO NORTHWEST
WINDS ACROSS THE LAKE IN THAT TIME.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-ILZ012-
ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-ILZ032...9
PM FRIDAY TO 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ003-ILZ004...9 PM FRIDAY TO 6 PM
SATURDAY.
WINTER STORM WATCH...ILZ033-ILZ039...MIDNIGHT SATURDAY TO 6 PM
SATURDAY.
IN...WINTER STORM WARNING...INZ001-INZ002...9 PM FRIDAY TO 6 PM
SATURDAY.
WINTER STORM WATCH...INZ010-INZ011-INZ019...MIDNIGHT SATURDAY TO
6 PM SATURDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1102 AM CST Fri Jan 31 2014
.DISCUSSION...
ISSUED 934 AM CST Fri Jan 31 2014
Have made changes to grids and zones this morning to reflect
earlier saturation and onset of precip and have tweeked other
elements to reflect. Light overrunning precipitation across cold
front over southern Illinois will continue today. Boundary Layer
has saturadted faster than earlier model indicated and snow is
reaching ground throughout central Illinois. Have updated to
reflect this as well as increase accumulation for today - still
an inch or less though.
Barker
&&
.AVIATION...
ISSUED 1102 AM CST Fri Jan 31 2014
Latest NAM and HRRR continue to indicate weak disturbances
enhancing general area of lift over forecast area. They both
suggest a lull this afternoon prior to next wave bringing in
precip this evening. Another lull after 06z is suggected before
main event on Saturday. Models have trended warmer and suggest
that a variety of precip types will be possible. Will generally
follow precip type suggested by NAM, but with a slightly warmer
scenario given the model trends.
Will keep generally MVFR with occasional IFR Cigs today and then
keep IFR conditions in place beginning this evening with the next
wave of precip.
Wind direction will depend on how far north front pushes ahead of
the Saturday`s sfc system which remains in flux. However, speeds
should be on the low side.
Barker
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Fri Jan 31 2014
Will continue the winter storm watch along and north of I-72 from
9 pm this Friday evening until 6 pm Saturday. 00Z models continue
to shift mixed precipitation further nw and continued to adjust
the forecast in that direction with heaviest snowfall of 5-7 inches
nw of the IL river while heaviest ice band of two to three tenths
is between I-55 and I-72. Mainly rain over southeast IL tonight and
Saturday with little or no snow/ice accumulations south of I-70.
SHORT TERM...Today through Monday
Early morning surface map shows frontal boundary over central IN
into southeast IL near I-70 and into southern MO and extends to
997 mb low pressure over along the northern TX/NM border. Weak
1022 mb high pressure was near the IA/SD border. Temps early this
morning range from upper teens nw of the IL river to the mid 30s
from I-70 se. Radar mosaic shows very light snow bands or flurries
over northern MO and moving east into west central IL.
Frontal boundary near I-70 to push slowly south through southeast
IL during the morning and then be quasi-stationary for a time this
afternoon nw of the Ohio river and south of highway 50 before
starting to lift back north into southeast IL tonight. Weak
isentropic lift to occur north of this boundary today to help
develop light snow during the day and be more likely in the
afternoon and mainly occur north of I-70. If light precipitation
occurs in southeast IL this afternoon would be some light rain too.
Any snow accumulations today should less than 1 inch and mainly
from I-72 north. Highs today contrast from around 20F by Galesburg to
near 40F at Lawrenceville.
Low pressure near the TX/NM border to eject ne into the Ozarks by
12Z/6 am Sat with 1006 mb low pressure and into central IL by
18Z/noon Sat and to the southern lower MI border by 00Z/6 pm Sat.
More widespread and heavier precipitation to develop during
tonight from sw to ne especially overnight and Saturday morning.
Most of precipitation starts as snow this evening north of I-72
with a mix of freezing rain, sleet and snow south of I-72 while
mainly rain south of I-70. Mixed precipitation shifts nw toward
the IL river by Saturday morning while just rain falls south of
I-72 for a time Saturday morning while a mix of freezing rain,
sleet and snow north of I-72 to the IL river. Mainly snow falls nw
by Knox and Stark counties during this event. Colder air starts
moving in from the w/nw during Saturday afternoon changing the mix
precipitation back to snow west of I-55 though still a mix over
east central IL east of I-55 and rain in southeast IL. Snowfall
amounts of 4-7 inches over the IL river valley while 1-3 inches
over central CWA. Potential is there for a quarter inch or more of
ice se of the IL river to along I-72 while ice accumulations less
than a tenth inch from Charleston/Mattoon south with little or no
snow or ice south of I-70. Highs Sat range from around 30F nw of
IL river to near 50F far se at Lawrenceville. Light precipitation
changes to light snow Saturday evening over eastern IL as it
diminishes with less than 1 inch of accumulations. Most of light
snow to be east of IL overnight Sat night as colder air ushers in.
1033 mb high pressure moves over central IL by midnight Sunday
night and ensures dry and colder weather from Sunday through
Monday. Highs Sunday contrast from 10-15F over IL river valley to
25-30F in southeast IL. Lows to get to zero to 5 below zero
northern counties Sunday night where snow pack expected while
10-15F southeast of I-70. Highs Monday range from upper teens
north of I-70 to upper 20s to around 30F in southeast IL.
LONG TERM...Monday night through Thursday night
Extended models show a fairly strong southern stream storm system
ejecting ne from the southern plains into central KY/TN by sunset Tue.
Potential is there for another winter storm to impact parts of
central and southeast IL where mostly snow to fall this time
around Tue and Tue night with several inches while mixed
precipitation appears to be se of highway 50 on Tuesday. Storm
system pulls away on Wed as snow diminishes during Wed morning and
ushers in another arctic air mass as temps slip into the single
digits below zero Wed night and Thu night over much of central
IL.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH from 9 PM CST this evening through Saturday
afternoon FOR ILZ027>031-036>038-040>051-053.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1052 PM EST SAT FEB 1 2014
.UPDATE...
NEAR TERM SECTION FOR THE REST OF TONIGHT HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1052 PM EST SAT FEB 1 2014
PRECIPITATION HAVE ALREADY CHANGED OVER TO SNOW OVER NORTHWEST
SECTIONS AND THIS CHANGEOVER WILL PROGRESS SOUTHEAST ACROSS OUR
REGION WITH MOST AREAS POSSIBLY SEEING A FEW HOURS OF LIGHT FREEZING
RAIN AND SLEET AHEAD OF THE TRANSITION TO SNOW. RAP SOUNDINGS
INDICATE SURFACE TEMPERATURES WILL FALL QUICKER THAN TEMPERATURES
ALOFT AS BUFKIT INDICATES FREEZING RAIN AT INDY MOST OF THE NIGHT.
I BELIEVE THEY ARE OVERDOING THE FREEZING RAIN AMOUNTS AND THIS WARM
LAYER ALOFT. NORMALLY YOU DO NOT GET A BIG FREEZING RAIN EVENT
ALONG A COLD FRONT. SO EVEN THOUGH LIGHT FREEZING RAIN MAY OCCUR FOR
A FEW HOURS...I EXPECT ONLY VERY LIGHT ICING AT BEST. SO WILL
CONTINUE TO COVER THIS EVENT WITH A SPECIAL WEATHER STATEMENT.
THE CHANGEOVER TO FREEZING RAIN AND SLEET MAY NOT REACH FAR SOUTHERN
SECTIONS UNTIL 500 AM. EXPECT ALL AREAS TO SEE ICE ACCUMULATIONS
WELL UNDER A TENTH OF AN INCH. SNOW ACCUMULATIONS OF 1 TO 2 INCHES
POSSIBLE ACROSS OUR NORTH. MODELS INDICATE A WEAK UPPER WAVE WILL
TRACK ACROSS OUR REGION TOWARDS 4 AM AND PRECIPITATION SHOULD
DIMINISH RAPIDLY FROM THE NORTHWEST AFTER THAT.
RAISED TEMPERATURES A DEGREE OR TWO BASED ON MODEL SURFACE
TEMPERATURES. OTHERWISE...NO OTHER CHANGES MADE AT THIS TIME.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 257 PM EST SAT FEB 1 2014
FOCUS REMAINS POSSIBLE WINTER STORM TUESDAY INTO WEDNESDAY.
CONTINUE TO PREFER A BLEND OF GUIDANCE WITH LESS RELIANCE ON
SOMEWHAT LESS CONSISTENT GFS. GFS LOW TRACK HAS SHIFTED SLIGHTLY
SOUTHEAST AND EURO SLIGHTLY NORTHWEST...ALTHOUGH EURO REMAINS
CONSISTENTLY THE COLDER MODEL AND GFS WARMER ODDLY ENOUGH. GFS
ENSEMBLE MEMBERS REMAIN LOOSELY CLUSTERED BUT AROUND A FURTHER
SOUTHEAST TRACK THAN PREVIOUS DAYS...BUT THIS HAS YET TO TRANSLATE
TO A COLDER SOLUTION IN THE LOW LEVELS.
AS SUCH...WILL CONTINUE WITH ALL SNOW MAINLY NORTH/NORTHWEST OF
INDY...WITH A CHANCE OF SLEET/FREEZING RAIN MIXING IN A SWATH
SOUTH OF THIS...AND FREEZING RAIN/SLEET WITH A CHANCE OF SNOW
ACROSS THE FAR SOUTH LATE TUESDAY INTO TUESDAY EVENING. ALL PRECIP
AFTER 06Z WEDNESDAY LIKELY SNOW OR QUICKLY TRANSITIONING TO SNOW.
MESOSCALE FEATURES WILL BE IN PLAY AND AS SUCH AMOUNTS REMAIN VERY
DIFFICULT TO PINPOINT. BANDING WILL BE AN ISSUE WHICH COULD IMPACT
BOTH AMOUNTS AND PRECIP TYPE OWING TO DYNAMIC EFFECTS.
MESSAGE REMAINS THE SAME. CENTRAL INDIANA RESIDENTS SHOULD BE
PREPARED FOR A POSSIBLE WINTER STORM BEGINNING TUESDAY AND
CONTINUING INTO EARLY WEDNESDAY WITH THE POTENTIAL FOR
ACCUMULATING SNOW AND SLEET/ICE.
&&
.AVIATION /DISCUSSION FOR THE 020300Z KIND TAF UPDATE/...
ISSUED AT 930 PM EST SAT FEB 1 2014
THINGS SEEM TO BE ON TARGET SO FAR...ALTHOUGH SEEING LESS IN THE WAY
OF FREEZING RAIN AND SLEET SO FAR THAN WAS EXPECTED IN THE
TRANSITION ZONE. MAY END UP WITH MORE OF A RAIN TO SNOW
TRANSITION...BUT NOT CONVINCED ENOUGH TO CHANGE THINGS AT THIS TIME.
PREVIOUS DISCUSSION FOLLOWS.
DIFFICULT FORECAST WITH RESPECT TO PRECIPITATION TYPES AND CHANGE
OVER TIMING AS SHARP COLD FRONT WILL BE PASSING OVER THE TAF SITES
DURING THE NEXT SEVERAL HOURS WITH LIFTING OVER THE FRONT CONTINUING
WELL INTO THE EARLY MORNING HOURS ON SUNDAY.
COLD FRONT HAS PASSED THROUGH KLAF...WITH SHORT TERM MODEL DATA
SUGGESTING FRONT WILL CLEAR THE REMAINING TAF SITES BY 020200Z. COLD
ADVECTION LOOKS FAIRLY STRONG...WITH MODELS SUGGESTING THE ELEVATED
WARM LAYER DISAPPEARING WITHING ABOUT 4-6 HOURS AFTER FRONTAL
PASSAGE...SUGGESTING A CHANGEOVER TO SNOW BY THAT TIME. WILL USE
THIS THINKING TO TIME THE CHANGEOVER AT THE TAF SITES TONIGHT. GOOD
POTENTIAL FOR A PERIOD OF FREEZING RAIN/SLEET AS WELL EMBEDDED
WITHIN THE TRANSITION ZONE. APPEARS SURFACE FREEZING LINE WILL BE
CLOSE TO KLAF BY ISSUANCE TIME...SO WILL START THAT SITE WITH
FREEZING RAIN.
OTHERWISE...GENERALLY EXPECTING AREAS OF IFR VISIBILITY RESTRICTIONS
IN RAIN AND FOG AHEAD OF THE FRONT...WITH IFR CEILINGS AROUND
005-006 AGL ALONG WITH IFR VISIBILITY RESTRICTIONS ONCE THE
PRECIPITATION CHANGES OVER TO SNOW.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...JH
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
903 PM EST SAT FEB 1 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN SHOWERS CONTINUE TO IMPACT THE NORTHWEST HALF OF THE FORECAST
AREA THIS AFTERNOON. QUITE THE TEMPERATURE GRADIENT AT 20Z AS WARM
ADVECTION HAS DRAWN MUCH WARMER AIR INTO THE OHIO VALLEY. TEMPS
RANGED FROM THE MID/UPPER 30S OVER THE NORTHERN WABASH VALLEY TO THE
LOWER 50S OVER FAR SOUTHERN COUNTIES.
STARTING OFF A NEW MONTH WITH THE SAME OLD STORY...ANOTHER SHOT OF
WINTRY WEATHER TONIGHT AS COLDER AIR SPILLS BACK INTO CENTRAL
INDIANA BEHIND A COLD FRONT. THE FRONT WILL MOVE SOUTHEAST ACROSS
THE FORECAST AREA TONIGHT BUT AT A SLOW PACE AS THE BOUNDARY BECOMES
NEARLY STATIONARY TO THE MEAN UPPER FLOW. THE RESULT FROM THIS WILL
BE FOR NEAR SURFACE COOLING TO COMMENCE AT A FASTER PACE THAN THE
ADVECTION OF BOUNDARY LAYER COOLING OVER THE PRECIP SHIELD BEGINNING
OVER THE NORTHWEST THIS EVENING...EXPANDING SOUTHEAST ACROSS THE
FORECAST AREA OVERNIGHT.
LOW LEVEL THERMAL PROFILES BECOMING INCREASINGLY SUPPORTIVE OF A
MESSIER TRANSITION PERIOD OF 1-3 HOURS WITH A WINTRY MIX OF FREEZING
RAIN...SLEET AND SNOW BEFORE THE COLUMN COOLS ENOUGH TO SUPPORT ALL
SNOW. CURRENT HRRR EVEN HINTS AT THE POTENTIAL FOR SOME BANDING TO
SNOW OVER NORTHWEST COUNTIES THIS EVENING WHICH MAY SERVE TO
TRANSFER TO SNOW MORE QUICKLY AND PRODUCE ACCUMS OF 1 TO 2 INCHES
WITH EVEN LOCALLY HIGHER AMOUNTS ACROSS THE NORTHERN WABASH VALLEY.
FURTHER SOUTH AND EAST...EXPECT LIGHT ACCUMS OF ICE AND SNOW. OTHER
THAN FAR SOUTHEAST COUNTIES... EXPECT PRECIP FALLING AS ALL SNOW
OVER MOST AREAS AFTER 08-09Z. LIGHT SNOW WILL END FROM THE NORTHWEST
LATE TONIGHT.
HAVE CHOSEN TO ISSUE AN SPS FOR TONIGHT TO HIGHLIGHT THE LIGHT
SNOW/ICE ACCUMS AND POTENTIAL FOR SLICK SPOTS WITH REFREEZING AS
TEMPS FALL. AT THIS POINT...UNCERTAINTY REMAINS JUST TOO HIGH TO
WARRANT ISSUING AN ADVISORY AS TIMING OF THE CHANGEOVER AND EXTENT
OF TIME A CERTAIN PRECIP TYPE FALLS WILL BE CRITICAL IN DETERMINING
SNOW AND ICE AMOUNTS. EVENING SHIFT WILL CONTINUE TO MONITOR AND
ADJUST AS NEEDED.
TEMPS...USED NAM HOURLIES FOR TEMPS OVER THE NEXT SEVERAL HOURS AS
THEY FALL IN THE WAKE OF THE FRONTAL PASSAGE. MOS GUIDANCE LOOKED
REASONABLE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 257 PM EST SAT FEB 1 2014
FOCUS REMAINS POSSIBLE WINTER STORM TUESDAY INTO WEDNESDAY.
CONTINUE TO PREFER A BLEND OF GUIDANCE WITH LESS RELIANCE ON
SOMEWHAT LESS CONSISTENT GFS. GFS LOW TRACK HAS SHIFTED SLIGHTLY
SOUTHEAST AND EURO SLIGHTLY NORTHWEST...ALTHOUGH EURO REMAINS
CONSISTENTLY THE COLDER MODEL AND GFS WARMER ODDLY ENOUGH. GFS
ENSEMBLE MEMBERS REMAIN LOOSELY CLUSTERED BUT AROUND A FURTHER
SOUTHEAST TRACK THAN PREVIOUS DAYS...BUT THIS HAS YET TO TRANSLATE
TO A COLDER SOLUTION IN THE LOW LEVELS.
AS SUCH...WILL CONTINUE WITH ALL SNOW MAINLY NORTH/NORTHWEST OF
INDY...WITH A CHANCE OF SLEET/FREEZING RAIN MIXING IN A SWATH
SOUTH OF THIS...AND FREEZING RAIN/SLEET WITH A CHANCE OF SNOW
ACROSS THE FAR SOUTH LATE TUESDAY INTO TUESDAY EVENING. ALL PRECIP
AFTER 06Z WEDNESDAY LIKELY SNOW OR QUICKLY TRANSITIONING TO SNOW.
MESOSCALE FEATURES WILL BE IN PLAY AND AS SUCH AMOUNTS REMAIN VERY
DIFFICULT TO PINPOINT. BANDING WILL BE AN ISSUE WHICH COULD IMPACT
BOTH AMOUNTS AND PRECIP TYPE OWING TO DYNAMIC EFFECTS.
MESSAGE REMAINS THE SAME. CENTRAL INDIANA RESIDENTS SHOULD BE
PREPARED FOR A POSSIBLE WINTER STORM BEGINNING TUESDAY AND
CONTINUING INTO EARLY WEDNESDAY WITH THE POTENTIAL FOR
ACCUMULATING SNOW AND SLEET/ICE.
&&
.AVIATION /DISCUSSION FOR THE 020300Z KIND TAF UPDATE/...
ISSUED AT 930 PM EST SAT FEB 1 2014
THINGS SEEM TO BE ON TARGET SO FAR...ALTHOUGH SEEING LESS IN THE WAY
OF FREEZING RAIN AND SLEET SO FAR THAN WAS EXPECTED IN THE
TRANSITION ZONE. MAY END UP WITH MORE OF A RAIN TO SNOW
TRANSITION...BUT NOT CONVINCED ENOUGH TO CHANGE THINGS AT THIS TIME.
PREVIOUS DISCUSSION FOLLOWS.
DIFFICULT FORECAST WITH RESPECT TO PRECIPITATION TYPES AND CHANGE
OVER TIMING AS SHARP COLD FRONT WILL BE PASSING OVER THE TAF SITES
DURING THE NEXT SEVERAL HOURS WITH LIFTING OVER THE FRONT CONTINUING
WELL INTO THE EARLY MORNING HOURS ON SUNDAY.
COLD FRONT HAS PASSED THROUGH KLAF...WITH SHORT TERM MODEL DATA
SUGGESTING FRONT WILL CLEAR THE REMAINING TAF SITES BY 020200Z. COLD
ADVECTION LOOKS FAIRLY STRONG...WITH MODELS SUGGESTING THE ELEVATED
WARM LAYER DISAPPEARING WITHING ABOUT 4-6 HOURS AFTER FRONTAL
PASSAGE...SUGGESTING A CHANGEOVER TO SNOW BY THAT TIME. WILL USE
THIS THINKING TO TIME THE CHANGEOVER AT THE TAF SITES TONIGHT. GOOD
POTENTIAL FOR A PERIOD OF FREEZING RAIN/SLEET AS WELL EMBEDDED
WITHIN THE TRANSITION ZONE. APPEARS SURFACE FREEZING LINE WILL BE
CLOSE TO KLAF BY ISSUANCE TIME...SO WILL START THAT SITE WITH
FREEZING RAIN.
OTHERWISE...GENERALLY EXPECTING AREAS OF IFR VISIBILITY RESTRICTIONS
IN RAIN AND FOG AHEAD OF THE FRONT...WITH IFR CEILINGS AROUND
005-006 AGL ALONG WITH IFR VISIBILITY RESTRICTIONS ONCE THE
PRECIPITATION CHANGES OVER TO SNOW.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
930 PM EST SAT FEB 1 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN SHOWERS CONTINUE TO IMPACT THE NORTHWEST HALF OF THE FORECAST
AREA THIS AFTERNOON. QUITE THE TEMPERATURE GRADIENT AT 20Z AS WARM
ADVECTION HAS DRAWN MUCH WARMER AIR INTO THE OHIO VALLEY. TEMPS
RANGED FROM THE MID/UPPER 30S OVER THE NORTHERN WABASH VALLEY TO THE
LOWER 50S OVER FAR SOUTHERN COUNTIES.
STARTING OFF A NEW MONTH WITH THE SAME OLD STORY...ANOTHER SHOT OF
WINTRY WEATHER TONIGHT AS COLDER AIR SPILLS BACK INTO CENTRAL
INDIANA BEHIND A COLD FRONT. THE FRONT WILL MOVE SOUTHEAST ACROSS
THE FORECAST AREA TONIGHT BUT AT A SLOW PACE AS THE BOUNDARY BECOMES
NEARLY STATIONARY TO THE MEAN UPPER FLOW. THE RESULT FROM THIS WILL
BE FOR NEAR SURFACE COOLING TO COMMENCE AT A FASTER PACE THAN THE
ADVECTION OF BOUNDARY LAYER COOLING OVER THE PRECIP SHIELD BEGINNING
OVER THE NORTHWEST THIS EVENING...EXPANDING SOUTHEAST ACROSS THE
FORECAST AREA OVERNIGHT.
LOW LEVEL THERMAL PROFILES BECOMING INCREASINGLY SUPPORTIVE OF A
MESSIER TRANSITION PERIOD OF 1-3 HOURS WITH A WINTRY MIX OF FREEZING
RAIN...SLEET AND SNOW BEFORE THE COLUMN COOLS ENOUGH TO SUPPORT ALL
SNOW. CURRENT HRRR EVEN HINTS AT THE POTENTIAL FOR SOME BANDING TO
SNOW OVER NORTHWEST COUNTIES THIS EVENING WHICH MAY SERVE TO
TRANSFER TO SNOW MORE QUICKLY AND PRODUCE ACCUMS OF 1 TO 2 INCHES
WITH EVEN LOCALLY HIGHER AMOUNTS ACROSS THE NORTHERN WABASH VALLEY.
FURTHER SOUTH AND EAST...EXPECT LIGHT ACCUMS OF ICE AND SNOW. OTHER
THAN FAR SOUTHEAST COUNTIES... EXPECT PRECIP FALLING AS ALL SNOW
OVER MOST AREAS AFTER 08-09Z. LIGHT SNOW WILL END FROM THE NORTHWEST
LATE TONIGHT.
HAVE CHOSEN TO ISSUE AN SPS FOR TONIGHT TO HIGHLIGHT THE LIGHT
SNOW/ICE ACCUMS AND POTENTIAL FOR SLICK SPOTS WITH REFREEZING AS
TEMPS FALL. AT THIS POINT...UNCERTAINTY REMAINS JUST TOO HIGH TO
WARRANT ISSUING AN ADVISORY AS TIMING OF THE CHANGEOVER AND EXTENT
OF TIME A CERTAIN PRECIP TYPE FALLS WILL BE CRITICAL IN DETERMINING
SNOW AND ICE AMOUNTS. EVENING SHIFT WILL CONTINUE TO MONITOR AND
ADJUST AS NEEDED.
TEMPS...USED NAM HOURLIES FOR TEMPS OVER THE NEXT SEVERAL HOURS AS
THEY FALL IN THE WAKE OF THE FRONTAL PASSAGE. MOS GUIDANCE LOOKED
REASONABLE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 257 PM EST SAT FEB 1 2014
FOCUS REMAINS POSSIBLE WINTER STORM TUESDAY INTO WEDNESDAY.
CONTINUE TO PREFER A BLEND OF GUIDANCE WITH LESS RELIANCE ON
SOMEWHAT LESS CONSISTENT GFS. GFS LOW TRACK HAS SHIFTED SLIGHTLY
SOUTHEAST AND EURO SLIGHTLY NORTHWEST...ALTHOUGH EURO REMAINS
CONSISTENTLY THE COLDER MODEL AND GFS WARMER ODDLY ENOUGH. GFS
ENSEMBLE MEMBERS REMAIN LOOSELY CLUSTERED BUT AROUND A FURTHER
SOUTHEAST TRACK THAN PREVIOUS DAYS...BUT THIS HAS YET TO TRANSLATE
TO A COLDER SOLUTION IN THE LOW LEVELS.
AS SUCH...WILL CONTINUE WITH ALL SNOW MAINLY NORTH/NORTHWEST OF
INDY...WITH A CHANCE OF SLEET/FREEZING RAIN MIXING IN A SWATH
SOUTH OF THIS...AND FREEZING RAIN/SLEET WITH A CHANCE OF SNOW
ACROSS THE FAR SOUTH LATE TUESDAY INTO TUESDAY EVENING. ALL PRECIP
AFTER 06Z WEDNESDAY LIKELY SNOW OR QUICKLY TRANSITIONING TO SNOW.
MESOSCALE FEATURES WILL BE IN PLAY AND AS SUCH AMOUNTS REMAIN VERY
DIFFICULT TO PINPOINT. BANDING WILL BE AN ISSUE WHICH COULD IMPACT
BOTH AMOUNTS AND PRECIP TYPE OWING TO DYNAMIC EFFECTS.
MESSAGE REMAINS THE SAME. CENTRAL INDIANA RESIDENTS SHOULD BE
PREPARED FOR A POSSIBLE WINTER STORM BEGINNING TUESDAY AND
CONTINUING INTO EARLY WEDNESDAY WITH THE POTENTIAL FOR
ACCUMULATING SNOW AND SLEET/ICE.
&&
.AVIATION /DISCUSSION FOR THE 020300Z KIND TAF UPDATE/...
ISSUED AT 930 PM EST SAT FEB 1 2014
THINGS SEEM TO BE ON TARGET SO FAR...ALTHOUGH SEEING LESS IN THE WAY
OF FREEZING RAIN AND SLEET SO FAR THAN WAS EXPECTED IN THE
TRANSITION ZONE. MAY END UP WITH MORE OF A RAIN TO SNOW
TRANSITION...BUT NOT CONVINCED ENOUGH TO CHANGE THINGS AT THIS TIME.
PREVIOUS DISCUSSION FOLLOWS.
DIFFICULT FORECAST WITH RESPECT TO PRECIPITATION TYPES AND CHANGE
OVER TIMING AS SHARP COLD FRONT WILL BE PASSING OVER THE TAF SITES
DURING THE NEXT SEVERAL HOURS WITH LIFTING OVER THE FRONT CONTINUING
WELL INTO THE EARLY MORNING HOURS ON SUNDAY.
COLD FRONT HAS PASSED THROUGH KLAF...WITH SHORT TERM MODEL DATA
SUGGESTING FRONT WILL CLEAR THE REMAINING TAF SITES BY 020200Z. COLD
ADVECTION LOOKS FAIRLY STRONG...WITH MODELS SUGGESTING THE ELEVATED
WARM LAYER DISAPPEARING WITHING ABOUT 4-6 HOURS AFTER FRONTAL
PASSAGE...SUGGESTING A CHANGEOVER TO SNOW BY THAT TIME. WILL USE
THIS THINKING TO TIME THE CHANGEOVER AT THE TAF SITES TONIGHT. GOOD
POTENTIAL FOR A PERIOD OF FREEZING RAIN/SLEET AS WELL EMBEDDED
WITHIN THE TRANSITION ZONE. APPEARS SURFACE FREEZING LINE WILL BE
CLOSE TO KLAF BY ISSUANCE TIME...SO WILL START THAT SITE WITH
FREEZING RAIN.
OTHERWISE...GENERALLY EXPECTING AREAS OF IFR VISIBILITY RESTRICTIONS
IN RAIN AND FOG AHEAD OF THE FRONT...WITH IFR CEILINGS AROUND
005-006 AGL ALONG WITH IFR VISIBILITY RESTRICTIONS ONCE THE
PRECIPITATION CHANGES OVER TO SNOW.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
801 PM EST SAT FEB 1 2014
.SYNOPSIS...
ISSUED AT 526 PM EST SAT FEB 1 2014
A SLOW MOVING UPPER LEVEL SYSTEM WILL SHIFT EASTWARD
TONIGHT...EVENTUALLY SHIFTING PRECIPITATION EAST OF THE AREA LATE
TONIGHT INTO EARLY SUNDAY MORNING. COLDER AIR FILTERING INTO THE
REGION TONIGHT WILL ALLOW FOR PRECIPITATION TO CHANGEOVER TO SNOW
BEFORE ENDING ACROSS NORTHEAST INDIANA...NORTHWEST OHIO...AND
SOUTHEAST LOWER MICHIGAN. QUIET CONDITIONS ARE EXPECTED ON SUNDAY
AND MONDAY AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
HOWEVER...A STRONG STORM SYSTEM IS EXPECTED TO ORGANIZE ACROSS THE
SOUTHERN ROCKIES ON MONDAY...AND THEN BRING A POTENTIAL OF SOME
SIGNIFICANT SNOWFALL TO THE REGION FROM TUESDAY THROUGH EARLY WEDNESDAY.
&&
.UPDATE...
ISSUED AT 750 PM EST SAT FEB 1 2014
SFC REFLECTION HAS NOW TRACKED INTO FAR SOUTHEAST ONTARIO ALLOWING
LOCATIONS ACROSS NORTHWEST HALF OF THE AREA TO EXPERIENCE WIND
SHIFT TO THE NORTHWEST. PRECIP HAS TRANSITIONED BACK TO SNOW WITH
PERHAPS A VERY BRIEF PERIOD OF SOME SLEET BEFORE CHANGING OVER TO
SNOW. EXPECTING THIS BRIEF PERIOD OF MIXED PRECIP TO BE SHORT
LIVED AS IT PROGRESSES EASTWARD THROUGH THE REMAINDER OF THE
EVENING GIVEN VERY WEAK NATURE TO WARM LAYER ALOFT. MAIN LOW LEVEL
MOIST TONGUE WILL HAVE SHIFTED EAST OF THE AREA BY THE TIME PRECIP
CHANGES OVER TO SNOW...WITH SOME INITIALLY LOW SNOW:LIQUID RATIOS
AS THIS TRANSITION OCCURS. THIS SHOULD TEMPER ACCUMULATIONS
OVERNIGHT ALTHOUGH GIVEN POTENTIAL FOR SOME MODERATE PRECIP RATES
AT LEAST THROUGH 06Z...WILL HAVE TO KEEP AN EYE FOR SOME MORE
LOCALIZED HEAVIER SNOWFALL RATES. WHILE MOST OF ADDITIONAL SNOW
ACCUMULATION IS ANTICIPATED SOUTHEAST OF THE CURRENT WINTER STORM
WARNING AREA...HAVE OPTED TO CONTINUE THIS HEADLINE FOR NOW GIVEN
CONTINUED PERIODS OF SNOW AND SLUSHY/ICY ROAD CONDITIONS. WITH A
LOW AMPLITUDE PATTERN IN PLACE AND INITIAL SHORT WAVE NOW MORE
SHEARED IN NATURE AND RACING ACROSS SOUTHEAST ONTARIO...MAY TEND
TO SEE LOW LEVEL TROUGH SLOW ITS EASTWARD PROGRESSION OVERNIGHT
WHICH ALREADY SEEMS WELL HANDLED IN GRIDDED FORECAST. 00Z RAP
INITIALIZATION SEEMS TO HAVE PICKED UP ON A WEAK SHORT WAVE ACROSS
NORTHEAST ILLINOIS WHICH WILL TRACK INTO SOUTHERN LOWER MICHIGAN
OVERNIGHT. THIS FEATURE MAY RESULT IN SOME LOW/MID LEVEL
FRONTOGENESIS RESPONSE ACROSS THE AREA OVERNIGHT. NAM CROSS
SECTIONS DO ALSO DEPICT SOME ELEVATED INSTABILITY LINGERING
ESPECIALLY ACROSS SOUTHEAST THIRD OF THE AREA IN THE 06Z-12Z
TIMEFRAME. THUS...SOME LOW END CONCERN FOR BAND OF ENHANCED SNOW
ACROSS THESE LOCATIONS WHERE SOME WEAK-MODERATE 850-700 HPA FGEN
FORCING IS ANTICIPATED OVERNIGHT IN PROXIMITY TO WEAKER STABILITY
ALOFT. HOWEVER AT THIS TIME...GIVEN RELATIVELY LOW SNOW:LIQUID
RATIOS AND DEEPER MOISTURE ADVECTING EAST OF THE AREA...WILL LIMIT
ACCUMS TO 1 TO 3 INCHES. UPDATED FORECAST SENT TO ACCOUNT FOR
CURRENT POP/TEMP TRENDS.
&&
.SHORT TERM...(THROUGH TONIGHT)
ISSUED AT 337 PM EST SAT FEB 1 2014
...MESSY AFTERNOON/EVENING ON TAP FOR THE AREA...
AS OF 230 PM...LOCATIONS SOUTH OF A KANKAKEE...TO GOSHEN TO ANGOLA
LINE WERE SEEING ALL RAIN AS TEMPERATURES WERE IN THE MIDDLE 30S TO
NEAR 40 (FAR SOUTHEAST). PRIOR TO MIXING/SWITCHOVER...NUMEROUS
REPORTS OF 3 TO 5 INCHES OF SNOW CAME IN ACROSS THE WARNING AREA
WITH ANYWHERE FROM 1 TO 4 INCHES. BROAD AREA OF LOW PRESSURE WAS
LOCATED SOMEWHERE NEAR WHITE COUNTY...A BIT FURTHER NORTHWEST THAN
EXPECTED. RUC HAS BEEN HANDLING MANY OF THE FINER DETAILS QUITE WELL
AND WAS USED ALMOST EXCLUSIVELY FOR THE FORECAST INTO THIS EVENING.
THE LOW SHOULD TRACK ACROSS THE CENTRAL PORTIONS OF THE CWA BUT
ALSO SHOWING A FASTER TREND SO PREVIOUSLY THOUGHT CHANGE OVER TIMES
STILL LOOK REASONABLE. AS THE TRANSITION COMMENCES A BRIEF PERIOD OF
SLEET/FREEZING RAIN MAY OCCUR. ONCE THIS OCCURS...SEVERAL HOURS OF
SNOW IS EXPECTED WITH ADDITIONAL QPF VALUES OF ROUGHLY ONE QUARTER
INCH OR SO IN FAR NW AREAS TO A BAND OF THREE QUARTERS OF AN INCH OR
MORE IN SE HALF OR SO. MUCH OF THIS HEAVIER PRECIP WILL FALL IN THE
FORM OF RAIN...BUT MUCH LIKE FURTHER NW A QUARTER TO THIRD OF AN
INCH WILL LIKELY FALL AS SNOW. JUST AS WAS THE CASE EARLIER
TODAY...TOO MUCH UNCERTAINTY CONTINUES IN TRANSITION TO WARRANT ANY
HEADLINE CHANGES. IT COULD BE CLOSE FOR FULL WARNING CRITERIA BEING
MET IN SOME AREAS...BUT WARNING WAS ISSUED FOR A COMBINATION OF
EARLIER SNOW AND EXPECTED SNOW BEHIND THE LOW SO SHOULD WORK OUT FOR
THE MOST PART. FURTHER UPDATES AND REFINEMENTS ARE LIKELY INTO THIS
EVENING. NEEDLESS TO SAY...ONCE TEMPS START TO FALL..ROAD CONDITIONS
WILL BECOME MESSY AND VERY SLIPPERY WELL INTO THE OVERNIGHT HOURS.
&&
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 337 PM EST SAT FEB 1 2014
ENERGETIC IMPULSE LADEN FLW EMBEDDED WITHIN PROJECTED NEG PNA PATTN
ACRS NOAM SPELLS HIGH IMPACT WX ACRS THE OH VALLEY THIS PD. OF NOTE
CONTS TO BE W/SYS SEEN THIS AFTN ON VAPOR OUT NR 42N/137W WHICH DIGS
SEWD INTO NRN BAHA ON MON AND THEN LIFTS OUT THROUGH THE LWR OH
VALLEY AS LARGER SCALE ARCTIC STREAM SW DROPS SWD INTO THE WRN US.
PRONOUNCED POLAR RIDGING BLDG IN WAKE OF SHRT TERM SYS PASSAGE TO
PROVIDE A BRIEF DRY BUT COLD RESPITE FROM WINTERS ONSLAUGHT. HWVR
DEEP SRN PLAINS EJECTION POINT AND STG GOMEX RTN FLW INTO SRN
PERIPHERY OF RETREATING SFC RIDGE LOOK TO PROVIDE FOR SIG CYCLONE
DVLPMNT OVR THE LWR MS VALLEY EARLY TUE AND UP THROUGH THE ERN OH
VALLEY ON WED AS EXEMPLIFIED IN STABLE SPECTRAL TRACK. DETAILS AS
YET TO BE IRONED OUT BUT SIG IMPACTS XPCD BOTH W/WIND AND SNOW
PARTICULARLY TUE AFTN-WED AM.
OTRWS ARCTIC RIDGE BLDS EWD OUT OF THE PLAINS THU-FRI W/VERY COLD
TEMPS YET LOOKS TO SET THE STAGE FOR YET ANOTHER SIG OH VALLEY
CYCLONE NXT WEEKEND AS DEEP WRN TROUGH RELOADS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 526 PM EST SAT FEB 1 2014
PRIMARY AVIATION FORECAST CONCERN THIS EVENING WILL BE ONGOING
PRECIP EVENT AND PRECIP TYPE CHANGEOVER TIMING AT KFWA.
A LOW LEVEL THERMAL RIDGE HAS ADVECTED INTO THE AREA ALLOWING FOR
MOST OF NORTHERN INDIANA TO HAVE SWITCHED OVER TO A PERIOD OF RAIN
THIS AFTERNOON. SFC REFLECTION OF THIS SYSTEM HAS SHIFTED INTO
SOUTHEAST LOWER MICHIGAN WHICH HAS ALLOWED FOR WIND SHIFT TO THE
NORTHWEST ACROSS NORTH CENTRAL INDIANA INCLUDING KSBN. THIS WIND
SHIFT WILL PROGRESS SOUTHEASTWARD THIS EVENING ALLOWING COLDER AND
DRIER LOW LEVEL AIR TO ADVECT SOUTHEASTWARD. A VORT MAX ACROSS
EASTERN IOWA/NORTHWEST ILLINOIS WILL LIFT INTO LOWER MICHIGAN
LATER THIS EVENING WHICH SHOULD LEAD TO SOME ENHANCEMENT OF LOW
LEVEL FRONTOGENESIS ACROSS THE AREA THIS EVENING AND SLOW WEST TO
EAST PROGRESSION OF BACK EDGE OF PRECIP. CHANGEOVER BACK TO SNOW
EXPECTED AT KFWA AROUND THE 01Z TIMEFRAME...WITH A BRIEF PERIOD OF
SOME SLEET POSSIBLE EARLY THIS EVENING. A QUICK COUPLE OF INCHES
OF SNOW COULD FALL AT KFWA THIS EVENING DEPENDING ON EXACT TIMING
OF CHANGEOVER AND ORIENTATION OF POTENTIAL FRONTOGENESIS BANDS...BUT
CONFIDENCE IN ACCUMULATIONS AT KFWA ARE QUITE LOW AT THIS TIME
GIVEN HIGH INITIAL WET BULB TEMPS. BULK OF PRECIP SHOULD SHIFT
EAST OF KFWA AFTER 06Z. IFR/TEMPO LIFR CONDS SHOULD IMPROVE TO
LOWER END MVFR OVERNIGHT...WITH FURTHER IMPROVEMENT EXPECTED ON
SUNDAY.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WARNING UNTIL 1 AM EST /MIDNIGHT CST/ SUNDAY FOR
INZ003>005-012-014.
MI...WINTER STORM WARNING UNTIL 1 AM EST SUNDAY FOR MIZ077>080.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...MARSILI
SYNOPSIS...MARSILI
SHORT TERM...FISHER
LONG TERM...T
AVIATION...MARSILI
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DULUTH MN
1258 PM CST FRI JAN 31 2014
.UPDATE...
ISSUED AT 1257 PM CST FRI JAN 31 2014
HAVE JUST SENT OUT AN UPDATE TO ALLOW WIND CHILL ADVISORY TO
EXPIRE WITH TEMPS NOW GENERALLY AROUND ZERO...WITH WIND CHILL
VALUES ABOVE 20 BELOW.
TONIGHT...WILL BE EVALUATING THE NEED FOR YET ANOTHER WIND CHILL
ADVISORY FOR AT LEAST A PART OF THE AREA...EVEN AS SOME LIGHT SNOW
MOVES INTO THE AREA AFTER MIDNIGHT TONIGHT.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
HIGH PRESSURE CENTERED SOUTHWEST OF THE NORTHLAND EARLY THIS MORNING
WILL SLIDE EAST TODAY WITH WINDS BECOMING SOUTHWEST. THE HIGH WAS
KEEPING MUCH OF THE NORTHLAND CLEAR...BUT SOME CLOUDS WERE AFFECTING
FAR NORTHERN MINNESOTA AND THEY WILL CONTINUE TO DO SO TODAY. THE
CLOUDS WILL LIKELY DIMINISH THROUGH THE LATE MORNING/EARLY
AFTERNOON...BUT THE RAP DOES SUGGEST REDEVELOPMENT WILL OCCUR LATER
THIS AFTERNOON OVER FAR NORTHEAST MINNESOTA. TEMPERATURES WERE IN
THE TEENS TO AROUND TWENTY BELOW AS OF 3 AM...WITH THE CLOUDS
KEEPING TEMPS UP AS THEY MOVE IN. SOME FLURRIES HAVE OCCURRED AS
WELL OUT OF THESE CLOUDS AND WE WILL ADD TO THE FORECAST FOR THIS
MORNING. HIGHS WILL ONLY GET INTO THE SINGLE DIGITS ABOVE ZERO
TODAY. WE WILL KEEP THE WIND CHILL GOING ACROSS ALL AREAS THIS
MORNING...ALTHOUGH PORTIONS MAY BE CANCELLED AROUND 10 AM.
A SHORTWAVE AND WAA...ESPECIALLY IN THE LOW LEVELS...WILL IMPACT THE
NORTHLAND TONIGHT INTO SATURDAY. WE INCREASED POPS FOR SOME LIGHT
SNOW LATE TONIGHT INTO SATURDAY...WITH THE BEST CHANCE OVER WESTERN
AREAS TONIGHT...AND EASTERN AREAS SATURDAY. LOWS TONIGHT WILL BE A
CHALLENGE...AS TEMPS SHOULD DROP QUICKLY THIS EVENING BEFORE CLOUDS
THICKEN CAUSING TEMPS TO RISE. SNOW ACCUMULATIONS SHOULD BE
LIGHT...MAINLY UNDER AN INCH. HIGHS SATURDAY WILL RANGE FROM 5 TO 10
ABOVE OVER FAR NORTHERN MINNESOTA TO THE TEENS OVER NORTHWEST
WISCONSIN.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
LOW PRESSURE SYSTEM OVER THE GREAT LAKES SATURDAY EVENING WILL
CONTINUE TO TRACK TO THE E/NE SAT NIGHT WITH HIGH PRESSURE BUILDING
IN OVER THE CENTRAL US. COULD SEE A FEW LIGHT SNOW SHOWERS OVER
PARTS OF NRN WI THROUGH EARLY SUN MORNING...WITH VERY LIGHT LAKE
ENHANCEMENT. OTHERWISE...CONDITIONS WILL REMAIN DRY THROUGH THE
EARLY PART OF THE WEEK. A STRONG AREA OF LOW PRESSURE IS EXPECTED TO
DEVELOP OVER THE SRN/CENTRAL CONUS BY TUE AND LIFT TO THE NE INTO
THE OHIO VALLEY/ERN GREAT LAKES AREA BY WED. THE NWD EXTEND OF THE
PRECIP SHIELD IS STILL IN QUESTION AND COULD BRING LIGHT SNOW
SHOWERS TO SERN SECTIONS OF THE FORECAST AREA DURING THIS TIME. NO
SIGNIFICANT PRECIP IS EXPECTED FOR THE NORTHLAND...AND WILL LIKELY
JUST LEAD TO ADDITIONAL CLOUD COVER. THE OTHER CONCERN IN THE
EXTENDED PERIOD IS THE CONTINUED COLD CONDITIONS. TEMPERATURES
WILL REMAIN 20 DEG BELOW NORMAL...WITH HIGHS IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE TEENS BELOW ZERO THROUGH THE WEEK. WIND
CHILLS WILL ALSO REMAIN A CONCERN WITH ADDITIONAL ADVISORIES LIKELY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1132 AM CST FRI JAN 31 2014
VFR UNTIL 09Z WHEN MVFR CIGS WITH SOME LIGHT SNOW BEGINS TO AFFECT
THE TERMINALS. THE LIGHT SNOW AND MVFR WILL BE SHORT LIVED AS THE
SNOW SHOULD END FROM W TO E AFTER 15Z FOLLOWED BY AN IMPROVEMENT
TO VFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH -11 14 -11 5 / 30 40 10 0
INL -14 6 -18 3 / 20 20 10 0
BRD -8 14 -16 7 / 40 40 0 0
HYR -14 20 -13 6 / 10 40 20 0
ASX -10 18 -8 7 / 10 30 20 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...LE
SHORT TERM...MELDE
LONG TERM...BJT
AVIATION...GSF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1132 AM CST FRI JAN 31 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
HIGH PRESSURE CENTERED SOUTHWEST OF THE NORTHLAND EARLY THIS MORNING
WILL SLIDE EAST TODAY WITH WINDS BECOMING SOUTHWEST. THE HIGH WAS
KEEPING MUCH OF THE NORTHLAND CLEAR...BUT SOME CLOUDS WERE AFFECTING
FAR NORTHERN MINNESOTA AND THEY WILL CONTINUE TO DO SO TODAY. THE
CLOUDS WILL LIKELY DIMINISH THROUGH THE LATE MORNING/EARLY
AFTERNOON...BUT THE RAP DOES SUGGEST REDEVELOPMENT WILL OCCUR LATER
THIS AFTERNOON OVER FAR NORTHEAST MINNESOTA. TEMPERATURES WERE IN
THE TEENS TO AROUND TWENTY BELOW AS OF 3 AM...WITH THE CLOUDS
KEEPING TEMPS UP AS THEY MOVE IN. SOME FLURRIES HAVE OCCURRED AS
WELL OUT OF THESE CLOUDS AND WE WILL ADD TO THE FORECAST FOR THIS
MORNING. HIGHS WILL ONLY GET INTO THE SINGLE DIGITS ABOVE ZERO
TODAY. WE WILL KEEP THE WIND CHILL GOING ACROSS ALL AREAS THIS
MORNING...ALTHOUGH PORTIONS MAY BE CANCELLED AROUND 10 AM.
A SHORTWAVE AND WAA...ESPECIALLY IN THE LOW LEVELS...WILL IMPACT THE
NORTHLAND TONIGHT INTO SATURDAY. WE INCREASED POPS FOR SOME LIGHT
SNOW LATE TONIGHT INTO SATURDAY...WITH THE BEST CHANCE OVER WESTERN
AREAS TONIGHT...AND EASTERN AREAS SATURDAY. LOWS TONIGHT WILL BE A
CHALLENGE...AS TEMPS SHOULD DROP QUICKLY THIS EVENING BEFORE CLOUDS
THICKEN CAUSING TEMPS TO RISE. SNOW ACCUMULATIONS SHOULD BE
LIGHT...MAINLY UNDER AN INCH. HIGHS SATURDAY WILL RANGE FROM 5 TO 10
ABOVE OVER FAR NORTHERN MINNESOTA TO THE TEENS OVER NORTHWEST
WISCONSIN.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
LOW PRESSURE SYSTEM OVER THE GREAT LAKES SATURDAY EVENING WILL
CONTINUE TO TRACK TO THE E/NE SAT NIGHT WITH HIGH PRESSURE BUILDING
IN OVER THE CENTRAL US. COULD SEE A FEW LIGHT SNOW SHOWERS OVER
PARTS OF NRN WI THROUGH EARLY SUN MORNING...WITH VERY LIGHT LAKE
ENHANCEMENT. OTHERWISE...CONDITIONS WILL REMAIN DRY THROUGH THE
EARLY PART OF THE WEEK. A STRONG AREA OF LOW PRESSURE IS EXPECTED TO
DEVELOP OVER THE SRN/CENTRAL CONUS BY TUE AND LIFT TO THE NE INTO
THE OHIO VALLEY/ERN GREAT LAKES AREA BY WED. THE NWD EXTEND OF THE
PRECIP SHIELD IS STILL IN QUESTION AND COULD BRING LIGHT SNOW
SHOWERS TO SERN SECTIONS OF THE FORECAST AREA DURING THIS TIME. NO
SIGNIFICANT PRECIP IS EXPECTED FOR THE NORTHLAND...AND WILL LIKELY
JUST LEAD TO ADDITIONAL CLOUD COVER. THE OTHER CONCERN IN THE
EXTENDED PERIOD IS THE CONTINUED COLD CONDITIONS. TEMPERATURES
WILL REMAIN 20 DEG BELOW NORMAL...WITH HIGHS IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE TEENS BELOW ZERO THROUGH THE WEEK. WIND
CHILLS WILL ALSO REMAIN A CONCERN WITH ADDITIONAL ADVISORIES LIKELY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1132 AM CST FRI JAN 31 2014
VFR UNTIL 09Z WHEN MVFR CIGS WITH SOME LIGHT SNOW BEGINS TO AFFECT
THE TERMINALS. THE LIGHT SNOW AND MVFR WILL BE SHORT LIVED AS THE
SNOW SHOULD END FROM W TO E AFTER 15Z FOLLOWED BY AN IMPROVEMENT
TO VFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 2 -11 14 -11 / 0 30 40 10
INL 1 -14 6 -18 / 10 20 20 10
BRD 4 -8 14 -16 / 0 40 40 0
HYR 5 -14 20 -13 / 0 10 40 20
ASX 7 -10 18 -8 / 0 10 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR MNZ010>012-018>021-
025-026-033>038.
WI...WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR WIZ001>004-006>009.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...BJT
AVIATION...GSF
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
530 AM CST FRI JAN 31 2014
.UPDATE...
ISSUED AT 530 AM CST FRI JAN 31 2014
UPDATED FOR AVIATION DISCUSSION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
HIGH PRESSURE CENTERED SOUTHWEST OF THE NORTHLAND EARLY THIS MORNING
WILL SLIDE EAST TODAY WITH WINDS BECOMING SOUTHWEST. THE HIGH WAS
KEEPING MUCH OF THE NORTHLAND CLEAR...BUT SOME CLOUDS WERE AFFECTING
FAR NORTHERN MINNESOTA AND THEY WILL CONTINUE TO DO SO TODAY. THE
CLOUDS WILL LIKELY DIMINISH THROUGH THE LATE MORNING/EARLY
AFTERNOON...BUT THE RAP DOES SUGGEST REDEVELOPMENT WILL OCCUR LATER
THIS AFTERNOON OVER FAR NORTHEAST MINNESOTA. TEMPERATURES WERE IN
THE TEENS TO AROUND TWENTY BELOW AS OF 3 AM...WITH THE CLOUDS
KEEPING TEMPS UP AS THEY MOVE IN. SOME FLURRIES HAVE OCCURRED AS
WELL OUT OF THESE CLOUDS AND WE WILL ADD TO THE FORECAST FOR THIS
MORNING. HIGHS WILL ONLY GET INTO THE SINGLE DIGITS ABOVE ZERO
TODAY. WE WILL KEEP THE WIND CHILL GOING ACROSS ALL AREAS THIS
MORNING...ALTHOUGH PORTIONS MAY BE CANCELLED AROUND 10 AM.
A SHORTWAVE AND WAA...ESPECIALLY IN THE LOW LEVELS...WILL IMPACT THE
NORTHLAND TONIGHT INTO SATURDAY. WE INCREASED POPS FOR SOME LIGHT
SNOW LATE TONIGHT INTO SATURDAY...WITH THE BEST CHANCE OVER WESTERN
AREAS TONIGHT...AND EASTERN AREAS SATURDAY. LOWS TONIGHT WILL BE A
CHALLENGE...AS TEMPS SHOULD DROP QUICKLY THIS EVENING BEFORE CLOUDS
THICKEN CAUSING TEMPS TO RISE. SNOW ACCUMULATIONS SHOULD BE
LIGHT...MAINLY UNDER AN INCH. HIGHS SATURDAY WILL RANGE FROM 5 TO 10
ABOVE OVER FAR NORTHERN MINNESOTA TO THE TEENS OVER NORTHWEST
WISCONSIN.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
LOW PRESSURE SYSTEM OVER THE GREAT LAKES SATURDAY EVENING WILL
CONTINUE TO TRACK TO THE E/NE SAT NIGHT WITH HIGH PRESSURE BUILDING
IN OVER THE CENTRAL US. COULD SEE A FEW LIGHT SNOW SHOWERS OVER
PARTS OF NRN WI THROUGH EARLY SUN MORNING...WITH VERY LIGHT LAKE
ENHANCEMENT. OTHERWISE...CONDITIONS WILL REMAIN DRY THROUGH THE
EARLY PART OF THE WEEK. A STRONG AREA OF LOW PRESSURE IS EXPECTED TO
DEVELOP OVER THE SRN/CENTRAL CONUS BY TUE AND LIFT TO THE NE INTO
THE OHIO VALLEY/ERN GREAT LAKES AREA BY WED. THE NWD EXTEND OF THE
PRECIP SHIELD IS STILL IN QUESTION AND COULD BRING LIGHT SNOW
SHOWERS TO SERN SECTIONS OF THE FORECAST AREA DURING THIS TIME. NO
SIGNIFICANT PRECIP IS EXPECTED FOR THE NORTHLAND...AND WILL LIKELY
JUST LEAD TO ADDITIONAL CLOUD COVER. THE OTHER CONCERN IN THE
EXTENDED PERIOD IS THE CONTINUED COLD CONDITIONS. TEMPERATURES
WILL REMAIN 20 DEG BELOW NORMAL...WITH HIGHS IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE TEENS BELOW ZERO THROUGH THE WEEK. WIND
CHILLS WILL ALSO REMAIN A CONCERN WITH ADDITIONAL ADVISORIES LIKELY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 530 AM CST FRI JAN 31 2014
VFR CONDITIONS ARE EXPECTED MOST OF TODAY AND THIS EVENING BEFORE
A PUSH OF MVFR CIGS AND VSBYS ARRIVE LATE TONIGHT WITH LIGHT SNOW
ASSOCIATED WITH A WEAK UPPER TROUGH FROM THE NW...COMBINING WITH A
PASSING LOW PRESSURE SYSTEM TO THE SOUTH. LIGHT SW WINDS THIS
MORNING WILL INCREASE THIS AFTERNOON BEFORE DIMINISHING AND
BACKING TO THE SOUTH TONIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 2 -11 14 -11 / 0 30 40 10
INL 1 -14 6 -18 / 10 20 20 10
BRD 4 -8 14 -16 / 0 40 40 0
HYR 5 -14 20 -13 / 0 10 40 20
ASX 7 -10 18 -8 / 0 10 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR MNZ010>012-018>021-
025-026-033>038.
WI...WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR WIZ001>004-006>009.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...BJT
AVIATION...BJT
AREA FORECAST DISCUSSION
NWS DULUTH MN
305 AM CST FRI JAN 31 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
HIGH PRESSURE CENTERED SOUTHWEST OF THE NORTHLAND EARLY THIS MORNING
WILL SLIDE EAST TODAY WITH WINDS BECOMING SOUTHWEST. THE HIGH WAS
KEEPING MUCH OF THE NORTHLAND CLEAR...BUT SOME CLOUDS WERE AFFECTING
FAR NORTHERN MINNESOTA AND THEY WILL CONTINUE TO DO SO TODAY. THE
CLOUDS WILL LIKELY DIMINISH THROUGH THE LATE MORNING/EARLY
AFTERNOON...BUT THE RAP DOES SUGGEST REDEVELOPMENT WILL OCCUR LATER
THIS AFTERNOON OVER FAR NORTHEAST MINNESOTA. TEMPERATURES WERE IN
THE TEENS TO AROUND TWENTY BELOW AS OF 3 AM...WITH THE CLOUDS
KEEPING TEMPS UP AS THEY MOVE IN. SOME FLURRIES HAVE OCCURRED AS
WELL OUT OF THESE CLOUDS AND WE WILL ADD TO THE FORECAST FOR THIS
MORNING. HIGHS WILL ONLY GET INTO THE SINGLE DIGITS ABOVE ZERO
TODAY. WE WILL KEEP THE WIND CHILL GOING ACROSS ALL AREAS THIS
MORNING...ALTHOUGH PORTIONS MAY BE CANCELLED AROUND 10 AM.
A SHORTWAVE AND WAA...ESPECIALLY IN THE LOW LEVELS...WILL IMPACT THE
NORTHLAND TONIGHT INTO SATURDAY. WE INCREASED POPS FOR SOME LIGHT
SNOW LATE TONIGHT INTO SATURDAY...WITH THE BEST CHANCE OVER WESTERN
AREAS TONIGHT...AND EASTERN AREAS SATURDAY. LOWS TONIGHT WILL BE A
CHALLENGE...AS TEMPS SHOULD DROP QUICKLY THIS EVENING BEFORE CLOUDS
THICKEN CAUSING TEMPS TO RISE. SNOW ACCUMULATIONS SHOULD BE
LIGHT...MAINLY UNDER AN INCH. HIGHS SATURDAY WILL RANGE FROM 5 TO 10
ABOVE OVER FAR NORTHERN MINNESOTA TO THE TEENS OVER NORTHWEST
WISCONSIN.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CST FRI JAN 31 2014
LOW PRESSURE SYSTEM OVER THE GREAT LAKES SATURDAY EVENING WILL
CONTINUE TO TRACK TO THE E/NE SAT NIGHT WITH HIGH PRESSURE BUILDING
IN OVER THE CENTRAL US. COULD SEE A FEW LIGHT SNOW SHOWERS OVER
PARTS OF NRN WI THROUGH EARLY SUN MORNING...WITH VERY LIGHT LAKE
ENHANCEMENT. OTHERWISE...CONDITIONS WILL REMAIN DRY THROUGH THE
EARLY PART OF THE WEEK. A STRONG AREA OF LOW PRESSURE IS EXPECTED TO
DEVELOP OVER THE SRN/CENTRAL CONUS BY TUE AND LIFT TO THE NE INTO
THE OHIO VALLEY/ERN GREAT LAKES AREA BY WED. THE NWD EXTEND OF THE
PRECIP SHIELD IS STILL IN QUESTION AND COULD BRING LIGHT SNOW
SHOWERS TO SERN SECTIONS OF THE FORECAST AREA DURING THIS TIME. NO
SIGNIFICANT PRECIP IS EXPECTED FOR THE NORTHLAND...AND WILL LIKELY
JUST LEAD TO ADDITIONAL CLOUD COVER. THE OTHER CONCERN IN THE
EXTENDED PERIOD IS THE CONTINUED COLD CONDITIONS. TEMPERATURES
WILL REMAIN 20 DEG BELOW NORMAL...WITH HIGHS IN THE SINGLE DIGITS
ABOVE ZERO AND LOWS IN THE TEENS BELOW ZERO THROUGH THE WEEK. WIND
CHILLS WILL ALSO REMAIN A CONCERN WITH ADDITIONAL ADVISORIES LIKELY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1148 PM CST THU JAN 30 2014
LARGELY VFR CONDITIONS ARE EXPECTED ACROSS THE NORTHLAND
THROUGHOUT THE TAF PERIOD...ALTHOUGH AN AREA OF MVFR CIGS WILL
MOVE ACROSS NORTHERN SITES OVERNIGHT AND INTO EARLY FRIDAY.
OTHERWISE IT WILL BE FAIRLY QUIET WITH MAINLY VFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 2 -11 14 -11 / 0 30 40 10
INL 1 -14 6 -18 / 10 20 20 10
BRD 4 -8 14 -16 / 0 40 40 0
HYR 5 -14 20 -13 / 0 10 40 20
ASX 7 -10 18 -8 / 0 10 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR MNZ010>012-018>021-
025-026-033>038.
WI...WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR WIZ001>004-006>009.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...BJT
AVIATION...DAP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1021 AM CST FRI JAN 31 2014
.UPDATE...
LOW STRATUS HAVE MOVED INTO THE REGION THIS MORNING...MAINLY ALONG/W
OF I-55. STRONGER WINDS/SLOWER MOISTURE RETURN/HIGHER DEWPOINT
DEPRESSIONS OVERNIGHT KEPT FOG FROM FORMING SO WE ONLY HAVE TO DEAL
WITH LOW CLOUDS FOR THE AFTERNOON. NAM/GFS BUFR SOUNDINGS INDICATE
MIXING OUT AND CLOUD COVER WILL GRADUALLY RETREAT TO THE W/NW TODAY
WHERE BETTER ISENTROPIC LIFT WILL BE PRESENT. TEMPS ARE CURRENTLY
COLDER IN THE E DUE TO A H925 TEMPERATURE TROUGH BUT RUC INDICATES
TEMPS WILL WARM INTO THE 8-10 DEG C RANGE. THE WARMING TEMPERATURES
ALOFT AND CLEARING SKIES TODAY WILL SUPPORT TEMPERATURES WARMING INTO
THE MID/UPPER 50S IN THE N TO LOW 60S IN THE SOUTH...WHICH IS ABOVE
CURRENT MAV GUIDANCE. DID NOT MODIFY HIGHS AS THEY LOOK CURRENTLY ON
TRACK. SLIGHTLY MODIFIED HOURLY TEMPS/DEWPOINTS ACCORDING TO CURRENT
TRENDS. ADJUSTED SKY COVER TO ACCOUNT FOR MOSTLY CLEAR SKIES IN THE E
CURRENTLY AND MIXING OUT OF LOW LEVEL CLOUDS IN CENTRAL/E MS TODAY.
REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...VFR CONDITIONS PREVAIL WITH BKN/OVC040 STRATUS DECK OVER
CENTRAL AND WESTERN TAF SITES WITH LESS CLOUD COVER FOR EAST
TERMINALS AT KGTR/KMEI/KHBG. STRATUS DECK WILL MIX OUT THROUGH THE
LATE MORNING/AFTERNOON TO SCT/BKN040-050 ACROSS THE REGION WITH
SOUTHEAST WINDS AROUND 10 KT. MVFR TO IFR CONDITIONS COULD BE
POSSIBLE OVERNIGHT WITH LOWER CIGS AND VISIBILITIES WITH SOME FOG
DEVELOPMENT FOR KHBG/KMEI/KGTR DOWN TO 3SM. WILL NEED TO MONITOR
TRENDS IF VIS CAN POTENTIALLY GET LOWER...ESPECIALLY TOWARDS KHBG.
/ALLEN/
&&
.PREV DISCUSSION... /ISSUED 415 AM CST FRI JAN 31 2014/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...FOR THE PERIOD THE ONLY
CONCERNS WILL BE THE WARMING TREND WITH SOME CHANCE OF RAIN FOR
TONIGHT THROUGH SATURDAY NIGHT...FOLLOWED BY A COLD FRONT ENTRANCE
ON SATURDAY NIGHT...THEN POPS AND TEMPS.
LATEST SATELLITE IMAGERY SHOWED A ZONAL PATTERN OVER THE REGION...WHICH
WAS PUSHING A MILDER AIRMASS INTO THE ARKLAMISS. THERE WAS GOOD MIXING
OCCURRING IN SOUTHERLY FLOW IN THE LOW LEVELS AND THE BOUNDARY LAYER
PRIOR TO DAWN ALONG WITH SOME CLOUDS SPREADING ACROSS THE REGION
FROM THE WEST. THIS WAS REDUCING OUR CHANCES OF ANY FOG ISSUES FOR THIS
MORNING. SO HAVE REMOVED THE MENTION OF ANY MORNING PATCHY FOG. ON
THE SURFACE LOW PRESSURE WAS NOTED ACROSS THE SOUTHERN PLAINS WHICH
WAS AIDING IN SOME WARM AIR ADVECTION FROM THE SOUTH IN THE LOW
LEVELS. A COLD FRONT WAS APPROACHING THE REGION FROM THE PLAINS.
FOR TODAY AND TONIGHT...EXPECT WARM ADVECTION TO CONTINUE ACROSS THE
REGION. EXPECT THE MORNING CLOUDS TO MIX OUT BY THIS AFTERNOON AS
SOUTHERLY FLOW WILL HELP TEMPS TO REBOUND TO AROUND NORMAL READINGS FOR
THIS TIME OF YEAR. HIGHS WILL RANGE FROM THE MIDDLE 50S NORTH TO THE
LOWER 60S SOUTH. REGIONAL CROSS SECTIONS AND SOUNDINGS SHOWS THAT
LOW LEVEL MOISTURE WILL INCREASE ACROSS THE REGION FOR TONIGHT. SO
EXPECT STRATUS TO PICK UP ALONG WITH SOME PATCHY FOG. LVORI SHOWED
SOME WIDESPREAD 10S ACROSS THE REGION. WE MAY BE ABLE TO SQUEEZE OUT
A FEW SPRINKLES IN THE NORTHWEST DUE TO WEAK ISENTROPIC LIFT. THIS
WAS PICKED UP TO A LIMITED EXTENT BY THE LOCAL WRF. PWATS IN THE
NORTHWEST WILL BE AROUND .80 OF AN INCH. SO KEPT MID TEEN POPS
THERE. LOWS TONIGHT WILL RANGE FROM THE 50S WEST TO THE 40S EAST.
FOR SATURDAY AND SATURDAY NIGHT...THE PATCHY FOG WILL LIFT BY MID
MORNING. LOW LEVEL MOISTURE WILL CONTINUE TO BE PREVALENT AS A COLD
FRONT PUSHES CLOSER TO THE REGION DURING SATURDAY. PWATS WILL
INCREASE TO AROUND ONE INCH. INSTABILITY WILL BE RATHER WEAK FOR ANY
CONVECTIVE POTENTIAL. SO EXPECT ISOLATED SHOWERS TO SPREAD ACROSS
THE REGION AS MOISTURE CONVERGENCE SLOWLY INCREASES AHEAD OF THE
FRONT. HIGHS WILL BE RATHER MILD AS 925 MB TEMPS PUSH INTO THE
11-14C RANGE. SO HIGHS WILL RANGE FROM THE LOWER TO UPPER 60S...WHICH
WILL PUSH TEMPS AROUND 5 TO 10 DEGREES ABOVE NORMAL. FOR SATURDAY
NIGHT THE COLD FRONT WILL ENTER THE DELTA REGION LATE. THIS WILL
INCREASE MOISTURE CONVERGENCE AS SHOWERS DEVELOP MAINLY ACROSS THE
NORTHWEST HALF. THIS WAS VERIFIED BY NATIONAL WRF MODELS. THERE MAY
BE SOME PATCHY FOG POTENTIAL ACROSS THE SOUTHEAST DURING THE
NIGHT...BUT ITS A LITTLE EARLY TO MENTION THAT FOR NOW. LOWS WILL
RANGE FROM THE LOWER 40S NORTHWEST TO THE MIDDLE 50S SOUTHEAST.
AS FAR AS TEMPS ARE CONCERN WENT CLOSE TO MAV GUIDANCE FOR TODAY.
FOR TONIGHT MADE SLIGHT ADJUSTMENTS TO THE MILDER SREF GUIDANCE AS
MOS LOOKED TO BE TOO COOL WITH THE EXPECTED LOW LEVEL MOISTURE IN
PLAY. FOR SATURDAY WENT CLOSER TO A BLEND OF GMOS AND SREF GUIDANCE
AS MAV LOOKED A LITTLE TOO COOL WHILE THE NAM WAS TOO WARM. FOR SATURDAY
NIGHT WENT WITH A BLEND OF NAM AND CURRENT FORECAST.
AS FAR AS POPS ARE CONCERN FOR TONIGHT WENT CLOSE TO CURRENT LOW
POPS IN THE NORTHWEST DELTA REGION AS MAV POPS LOOKED A LITTLE
DRY...WHILE THE NAM POPS WERE TOO WET. FOR SATURDAY WENT WITH THE SAME
CURRENT FORECAST POPS WITH THE SAME BIASES FOR THE MAV AND NAM POPS.
FOR SATURDAY NIGHT MADE SLIGHT ADJUSTMENTS TO MAV POPS. /17/
LONG TERM...THIS MED RANGE/LONG TERM IS GENERALLY IN LINE WITH THE
PREV EXTENDED FORECAST AND CONTINUES TO OFFER AN UP/DOWN TEMP REGIME
ALONG WITH A WETTER PERIOD FOR SUN-WED WHILE VARIOUS FRONTS LINGER
IN THE AREA. WHAT HAS INCREASED IS CONFIDENCE IN WARMER READINGS
ACROSS THE SE HALF SUN THEN ACROSS A LARGER PORTION OF THE CWA TUE.
CONFIDENCE IS ALSO INCREASING ON BETTER PRECIP CHANCES FOR SUNDAY
AFTERNOON/NIGHT AS MODELS ARE IN AGREEMENT ON A S/WV INCREASING WAA
OVER TOP OF THE FRONTAL BOUNDARY.
STARTING SUNDAY...LOOK FOR THE COLD FRONT TO BE INTO THE FAR NW CWA
WITH A SLOW STEADY SE PUSH THROUGH THE DAY. THE FRONTAL MOVEMENT
WILL SLOW WITH TIME AS LOW LEVEL WINDS WILL BACK AS DEEPER WAA FLOW
WILL DEVELOP IN RESPONSE TO THE APPROACHING S/WV EXPECTED FOR LATER
SUNDAY NIGHT. DUE TO THIS...THE SE HALF OF THE AREA WILL GET QUITE
WARM AND FAVORED THE WARMER NAM GUID TO MAX TEMPS. WHILE PRECIP WILL
EXIST MOST OF THE DAY...IT WON`T BE A WASH OUT. EXPECT A COUPLE
PERIODS OF PRECIP AND MOST OF IT ON THE LIGHTER SIDE. ALSO LOOK FOR
PRECIP TO EXPAND IN COVERAGE BY LATE AFTERNOON AS LIFT INCREASES.
HIGHER POPS WILL EXIST FOR SUNDAY NIGHT THANKS TO THE MORE FOCUSED
S/WV MOVING OVER THE CWA. WHILE SOME LOCALLY HIGHER AMTS COULD BE
POSSIBLE...IT SEEMS LIKE A DECENT .5 TO 1.0 IN TYPE RAINFALL SHOULD
OCCUR. THIS WILL BE WELCOME SINCE THE PAST COUPLE WEEKS HAVE BEEN
DRY. IN THE WAKE OF THE S/WV...THE SFC FRONT WILL GET A PUSH SE AND
COLDER AIR WILL FILTER IN.
MONDAY WILL REMAIN ON THE COOL SIDE AS PESKY CLOUDS WILL LINGER.
TEMPS WILL RANGE FROM THE MID 40S(NW) TO MID 50S(SE). MONDAY EVENING
WILL LIKELY BE THE PERIOD WHERE OVERNIGHT LOWS WILL BE MET BEFORE
READINGS WARM THROUGH SUNRISE. THIS WILL OCCUR AS THE LOW LEVELS
RESPOND TO AN APPROACHING S/WV WHICH WILL BE MORE POTENT THAN THE
SUNDAY SYSTEM. THROUGH EARLY TUE...A FRONTAL FEATURE WILL SHARPEN
AND REALLY SET UP A NICE BAROCLINIC ZONE LIKELY OVER A PART OF THE
NW CWA. THE INCREASING LIFT AND WAA OVERNIGHT WILL AID IN THE
DEVELOPMENT OF SHOWERS WITH EVEN A FEW TSRA OVER THE NW AREAS. THIS
ACTIVITY WILL BE FOCUSED AFTER MIDNIGHT TOWARD SUNRISE TUE.
ON TUE...WE WILL REALLY SEE A TEMP GRADIENT ACROSS THE REGION AS THE
EVOLVING FRONTAL SYSTEM STALLS...PIVOTS AS A SFC LOW RIDES NE ALONG
THE BOUNDARY. TEMPS ON THE WARM (SE) SECTOR WILL REACH THE 70-74
RANGE WHILE AREAS ON THE NW SIDE WILL HOLD IN THE 40S. MOST PRECIP
WILL BE FOCUSED ALONG AND NW OF THE FRONT WHILE THE WARM SECTOR WILL
BE CAPPED. THIS CAPPING SIGNAL HAS BEEN EVIDENT BY ALL GUID FOR THE
PAST COUPLE RUNS. BY TUE EVE...THE SFC LOW WILL LIFT NE AND THEN
PUSH A COLD FRONT THROUGH THE CWA. THERE WILL BE PRECIP ASSOCIATED
WITH THIS AND POPS WILL BE IN THE LIKELY CATEGORY TUE NIGHT. ONE
WOULD THINK SOME STRONG/SVR STORMS WOULD BE POSSIBLE WITH SUCH A
SYSTEM TAKING SHAPE THIS TIME OF YEAR. WHILE THIS IS A
POSSIBILITY...CONFIDENCE IN STRONG ACTIVITY OCCURRING IS ON THE LOW
SIDE. THIS IS MAINLY DUE TO THE MAIN ZONE OF LIFT MISSING OUR AREA
TO THE NW/N. WHILE SOME DECENT INGREDIENTS LOOK TO BE IN
PLACE...THERE LOOKS TO BE A DISCONNECT WITH THE BEST LIFT AND THAT
COMBINING WITH SVR WX PARAMETERS. WE WILL CONTINUE TO MONITOR.
IN THE WAKE OF THIS FRONT IS WHERE CONFIDENCE WANES AND THE FORECAST
GETS MORE TRICKY. THE GLOBAL MODELS SHOW THERE WILL BE AN EXPANSIVE
ARCTIC SFC HIGH TO SPREAD SOUTHWARD THROUGH THE PLAINS. THE CORE OF
THIS COLD WILL REMAIN WELL TO OUR NORTH AS THE UPPER PATTERN WILL
KEEP IT LOCKED UP FURTHER NORTH. HOWEVER...THIS AIR WILL BE SHALLOW
AND CONTAIN CHARACTERISTICS OF ARCTIC AIR (COLD/DRY). WHERE THE
MODELS DIFFER IS HOW THEY HANDLE THE MID/UPPER FLOW. THE EURO MORE
PRONOUNCED WITH THE SW FLOW WHILE THE GFS IS FLATTER AND HAS THE
ENERGY FURTHER W/SW. THIS FORECAST WILL LEAN MORE WITH THE
CONSISTENT EURO WHICH IS ALSO WHAT HPC HAS FOLLOWED. THIS WILL
RESULT IN COLDER TEMPS WED-FRI ALONG WITH AN INCREASE IN PRECIP BY
THU NIGHT INTO FRI. WHAT WILL COMPLICATE MATTERS IS THE COLD AIR
BEING IN PLACE WITH PRECIP MOVING IN. SOME SORT OF WINTRY PRECIP
APPEARS POSSIBLE WITH THIS PATTERN AND WILL HAVE A MENTION OF SUCH
ACROSS THE NORTH THU NIGHT. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 61 49 65 54 / 3 9 19 25
MERIDIAN 60 45 63 52 / 3 9 20 21
VICKSBURG 63 52 67 50 / 9 11 17 31
HATTIESBURG 63 50 67 57 / 3 12 20 21
NATCHEZ 62 52 68 55 / 9 9 16 23
GREENVILLE 56 52 65 41 / 10 15 23 51
GREENWOOD 56 50 64 44 / 10 13 18 46
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/ALLEN/17/CME
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
617 PM CST Sat Feb 1 2014
.UPDATE:
Issued at 607 PM CST Sat Feb 1 2014
Quick update to extend northern portions of winter weather
advisory until midnight CST. Band of light to occassionally
moderate snow in a southwest to northeast oriented band is moving
into the western CWA. 2100 UTC RAP captured this band very well
and primarily used that for POPS/QPF/snow amounts through 6Z. Up
to an inch is expected generally along a KCOU>>KPPQ line. Further
to the southeast...light precipitation is expected to gradually
turn from rain to freezing rain and eventually snow overnight
tonight with up to a half inch of snow in addition to a light
glazing of ice accretion expected. Latest HRRR/RAP runs also delay
ending of snowfall across portions of the area past midnight. This
is supported by NAM guidance which had fairly strong frontogenetic
circulation at 0600 UTC. Will monitor these areas further to the
south and east to see what develops and whether advisory may need
to be extended past midnight.
Gosselin
&&
.SHORT TERM: (Through Late Tonight)
Issued at 400 PM CST Sat Feb 1 2014
The next 7 days appears active with the current system and two more,
the first will be Tuesday into Tuesday Night and the second, Friday
through Saturday.
Current winter event will remain ongoing past 00Z. As far as
headlines are concerned with this fcst package issuance: 1) the
winter storm warning will be canceled 2) some of the counties in
the warning will be converted into a winter wx advy 3) the existing
winter wx advy will continue 4) more counties will be added to the
existing advy to the south and east of the metro area. If that
wasn`t confusing enough...a swath of counties through cntrl and
northeast Missouri into w cntrl IL will expire at 00Z. The rest of
the advy is set to expire at 06Z. The advys set to expire at 00Z are
for more of a wintry mix on the back edge of the main precip
shield. The rest of the advy area is more for FZRA.
The front that has been stalled to across our SE today had a wave of
low pressure move along it. This allowed temps to climb from just
above frzg in the NW portion of the STL metro area to the low 50s
across SE MO and sthrn IL. The low pressure wave is currently
exiting e cntrl IL into IN. Temps have been allowed to fall this
aftn in weak CAA. The ongoing precip across the sern half of the FA
is expected to slowly slide SE this evening. Decent lift and
frontogenetical forcing will keep precip going across SE MO into
sthrn IL most of the evening. Temps will be falling and the precip
should transition from ra to fzra with around a 0.05" of glaze
possible from near Steelville, MO NE through a good portion of the
STL metro and on to Hillsboro, IL. A band of light snow on the order
of around a half inch is possible from cntrl MO across the nthrn
portion of the STL metro and on NE into cntrl IL. The bulk of the
precip should be out of the SE CWA by 06Z.
Another wave of low pressure will ride NE along the front on Sunday.
There is a chance that some of the overrunning precip could make it
as far north as the eastern Ozarks Sunday aftn. This does not appear
to be a big deal...but could put down a few tenths of an inch of
snow.
SFC ridge builds in through the day on Sunday with below normal
temps. Did go a couple degrees warmer than MOS as guidance has been too
coll so far this winter with Arctic highs. High slides east on
Monday and Monday night with continued below normal temps.
Clouds will be on the increase Monday night in advance of the next
system. A vigorous 500 mb wave will induce cyclogenesis across the
sthrn High Plains Monday and Monday night. The sfc low is expected
to track from the lower MS valley into the OH valley..which is a
climatologically favored track for snow for the CWA. The 700 mb low
crosses the nthrn CWA and the 850 low crossed the sthrn CWA...so
most of the precip should be snow. Precip is expected to move into
cntrl MO around daybreak and continue to overspread the rest of the
area thru the day. Model soundings continue to indicate a mixed
precip event for locations south and east of the STL metro area. The
event should begin as fzra and/or sleet across the eastern Ozarks
and sthrn IL and should transition to all snow through the aftn
evening.
2%
.LONG TERM: (Sunday through Next Saturday)
Issued at 400 PM CST Sat Feb 1 2014
(Tuesday Night - Next Saturday)
The stormy pattern that we have been in the past few days will
continue thru at least late next week, leading one strong Pacific
storm system after another into our area, while maintaining a
healthy influence of cold Canadian air from the north. This will
certainly apply to a system scheduled to affect the area continuing
into Tuesday night and should also be the case with yet another
storm system for the end of the week into the early part of the
weekend.
By early Tuesday evening, the first storm system will be in a mature
enough phase to have nearly wrapped up the WAA portion of the event
and also have developed a deformation zone in addition. Pcpn-types
should be all snow nearly all locations, save some select areas of
SE MO and S IL, where a wintry mix expected for the early evening
only. The current iteration of the EC and GFS show the most
favorable track for heavy snow accums to be from just south of
Kansas City to just south of Quincy with a dry slot poking near the
STL metro and areas further south with some uncertainty with the
northern reaches of STL metro thru the Bowling Green area.
Wherever this heavy snow axis settles, significant snow
accumulation totals well in excess of 6" possible.
Wednesday thru Friday morning will be dominated by strong hi
pressure representing the latest outbreak of Arctic air into our
region. Accounting for the future deep snow cover favored currently
over our northern CWA, widespread sub-zero mins for both Thursday
and Friday morning possible. Wind will still be enough of a factor
Thursday morning that wind chills of -15 to -25 currently being
forecast.
Another storm system will then affect our region for later on Friday
and into Saturday, with an initial impulse slated for Friday
afternoon and into Friday night, and depending on how much the
system matures, another round looks possible into Saturday and
Saturday night for what could be a prolonged winter event.
Pcpn-types look to be primarily snow again, but some mix possible
for areas in SE MO and S IL.
TES
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1140 AM CST Sat Feb 1 2014
A mixed bag of light wintry precipitation will continue this
afternoon into the evening hours. Sleet and snow will give way to
freezing rain and freezing drizzle from northwest to southeast
across the area. Rain will prevail across much of southeast
Missouri into southwest Illinois through the afternoon. IFR
flight conditions will prevail. Expect wintry precipitation to end
from northwest to southeast this afternoon into the evening as the
stationary front currently draped across the I-44/I-55 corridor
begins pushing southeast. Precip types will run the gamut from
rain changing to freezing rain, then sleet and finally ending as
snow after 06Z. Low MVFR/IFR CIGS will likely prevail for several
hours after FROPA, then expect clearing.
Specifics for KSTL:
Precipitation type continues to be a huge challenge at Lambert.
The freezing line remains just to the northwest of the terminal,
but should be pushing southeast this afternoon. Expect rain to
change to freezing rain then a mix of freezing rain and sleet
ending with snow as the atmosphere cools. Timing is very uncertain
and the current forecast is low confidence. Regardless, IFR flight
conditions will continue to prevail at Lambert through at least
06-08Z.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY until Midnight CST tonight FOR Audrain
MO-Boone MO-Callaway MO-Cole MO-Crawford MO-Franklin MO-
Gasconade MO-Jefferson MO-Lincoln MO-Moniteau MO-Monroe MO-
Montgomery MO-Osage MO-Pike MO-Ralls MO-St. Charles MO-St.
Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve
MO-Warren MO-Washington MO.
IL...WINTER WEATHER ADVISORY until Midnight CST tonight FOR Bond IL-
Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Pike IL-Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1123 AM CST Fri Jan 31 2014
.SHORT TERM...(Today through Tomorrow)
Issued at 258 AM CST FRI JAN 31 2014
Very tricky forecast over the next 24 to 36 hours due to a surface
front in the area and two waves of precipitation moving through.
Temperatures and precip type is going to be challenging today
through tomorrow with a degree or two making a huge difference if
precip will be frozen or not.
There is a front basically near the I-44 corridor with
temperatures just below freezing north of that front and in the
middle 30s south of that front with the only exception over
towards West Plains where temperatures are actually in the middle
20s due to some localized clear skies. Ceilings are slowly
dropping and radar is starting to show some light echos developing
across southwest Missouri indicating that low level moisture is
beginning to move in.
The initial wave will develop very light precip in the form of
drizzle or freezing drizzle this morning through the afternoon.
The RUC models suggest that areas north of the spine of the Ozark
Plateau will likely stay in the lower 30s today and areas south of
the Plateau across far southern Missouri getting into the lower
40s. There will be a tight temperatures gradient across the CWA today.
Patchy freezing drizzle will be possible this morning for areas
north of I-44 through the early afternoon. Areas along the Highway
54 corridor will remain close to that freezing mark for most of
the day and will have the best potential of seeing either light
freezing rain or freezing drizzle through the afternoon hours.
An area of low pressure will ride up and along the front tonight
along with the main upper level wave moving through tonight. The
low pressure will move from southwest Missouri to east central
Missouri by Saturday morning. The best chance of precipitation
will be across central Missouri and the eastern Ozarks tonight
through tomorrow with lesser pops across the southwest corner of
the state and in southeast Kansas.
Expecting the best potential for freezing rain and sleet mix will
be across the Highway 54 corridor late tonight into tomorrow
morning where about a tenth of an inch of ice will be possible and
a dusting of light sleet or light snow when the precip wraps up
late Saturday morning. Areas along and north of I-44 will have a
window of seeing light freezing rain or light sleet mix perhaps
some light snow to end with tomorrow morning ending from west to
east Saturday afternoon.
Again...a light glaze of ice possible and a dusting of light sleet
or snow. At this time will let the current winter weather advisory
continue because of the threat of patchy freezing drizzle this
morning through early afternoon and then the risk for winter
weather late tonight into early Saturday morning.
.LONG TERM...(Saturday night through Friday)
Issued at 258 AM CST FRI JAN 31 2014
Cold Canadian airmass will settle in for the latter half of the
weekend into early next week. Have followed the ECMWF closely with
the latest trends from Sunday through the end of next week. There
will be an upper level wave moving south of the area Sunday
afternoon. There has been a slight trend to bring some precip
northward into southern Missouri Sunday afternoon. Will mention
light snow possible for extreme southern Missouri with best
chances south of our area. A light dusting may be possible for
areas of far southern Missouri.
The potential is increasing of a significant winter storm will
move in Monday night through Tuesday night. Models are converging
on a solution but still have some minor differences on thermal
profiles and amounts. Snow will begin to develop and move in late
Monday night into Tuesday morning with Tuesday morning through
early afternoon being the prime time for snow and some of it looks
like it could be heavy at times. There maybe some a wintry mix of
sleet and snow for areas over far southern Missouri.
Will start mentioning some decent accumulating snow looks
increasing likely for the Ozarks with this system. QPF will be on
the order of half an inch to an inch. At least several inches of
snowfall if not more seem very likely. This winter storm
potential will need to be watched closely through the weekend for
forecast trends. That storm system will move out of the area
Tuesday night.
Very cold airmass moves in for middle and end of next week with
fresh snow cover expected and high pressure overhead...temperatures
will be very cold and especially overnight lows. Long range models are
still indicating the potential of another significant winter storm
sometime by the end of next week as well. Very active weather
pattern starting this weekend through end of next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 1103 AM CST FRI JAN 31 2014
Expect IFR and occasional LIFR conditions to impact
Southwestern Missouri airfields for the duration of the TAF
forecast period. A weak to moderate strength winter storm system
approaching from the west is pulling gulf moisture northward.
This pattern coupled with a Canadian high pressure system to the
northeast pushing a cold and dry air flow to the south will
generate low ceilings...drizzle and occasional light rain over the
area the rest of today into early Saturday morning. A cold front
will move through the area later Saturday Morning bringing a good
shot at LIFR ceilings...and a period of rain changing to sleet
and snow toward late morning and mid day. Included low level wind
shear at all three airfields later tonight and early tomorrow due
to a low level southwesterly jet developing over the area.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...WINTER WEATHER ADVISORY until Noon CST Saturday FOR MOZ055>058-
066>071-077>081-088>091-094.
KS...WINTER WEATHER ADVISORY until Noon CST Saturday FOR KSZ073-097-
101.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Colucci
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
542 AM CST Fri Jan 31 2014
.SHORT TERM...(Today through Tomorrow)
Issued at 258 AM CST FRI JAN 31 2014
Very tricky forecast over the next 24 to 36 hours due to a surface
front in the area and two waves of precipitation moving through.
Temperatures and precip type is going to be challenging today
through tomorrow with a degree or two making a huge difference if
precip will be frozen or not.
There is a front basically near the I-44 corridor with
temperatures just below freezing north of that front and in the
middle 30s south of that front with the only exception over
towards West Plains where temperatures are actually in the middle
20s due to some localized clear skies. Ceilings are slowly
dropping and radar is starting to show some light echos developing
across southwest Missouri indicating that low level moisture is
beginning to move in.
The initial wave will develop very light precip in the form of
drizzle or freezing drizzle this morning through the afternoon.
The RUC models suggest that areas north of the spine of the Ozark
Plateau will likely stay in the lower 30s today and areas south of
the Plateau across far southern Missouri getting into the lower
40s. There will be a tight temperatures gradient across the CWA today.
Patchy freezing drizzle will be possible this morning for areas
north of I-44 through the early afternoon. Areas along the Highway
54 corridor will remain close to that freezing mark for most of
the day and will have the best potential of seeing either light
freezing rain or freezing drizzle through the afternoon hours.
An area of low pressure will ride up and along the front tonight
along with the main upper level wave moving through tonight. The
low pressure will move from southwest Missouri to east central
Missouri by Saturday morning. The best chance of precipitation
will be across central Missouri and the eastern Ozarks tonight
through tomorrow with lesser pops across the southwest corner of
the state and in southeast Kansas.
Expecting the best potential for freezing rain and sleet mix will
be across the Highway 54 corridor late tonight into tomorrow
morning where about a tenth of an inch of ice will be possible and
a dusting of light sleet or light snow when the precip wraps up
late Saturday morning. Areas along and north of I-44 will have a
window of seeing light freezing rain or light sleet mix perhaps
some light snow to end with tomorrow morning ending from west to
east Saturday afternoon.
Again...a light glaze of ice possible and a dusting of light sleet
or snow. At this time will let the current winter weather advisory
continue because of the threat of patchy freezing drizzle this
morning through early afternoon and then the risk for winter
weather late tonight into early Saturday morning.
.LONG TERM...(Saturday night through Friday)
Issued at 258 AM CST FRI JAN 31 2014
Cold Canadian airmass will settle in for the latter half of the
weekend into early next week. Have followed the ECMWF closely with
the latest trends from Sunday through the end of next week. There
will be an upper level wave moving south of the area Sunday
afternoon. There has been a slight trend to bring some precip
northward into southern Missouri Sunday afternoon. Will mention
light snow possible for extreme southern Missouri with best
chances south of our area. A light dusting may be possible for
areas of far southern Missouri.
The potential is increasing of a significant winter storm will
move in Monday night through Tuesday night. Models are converging
on a solution but still have some minor differences on thermal
profiles and amounts. Snow will begin to develop and move in late
Monday night into Tuesday morning with Tuesday morning through
early afternoon being the prime time for snow and some of it looks
like it could be heavy at times. There maybe some a wintry mix of
sleet and snow for areas over far southern Missouri.
Will start mentioning some decent accumulating snow looks
increasing likely for the Ozarks with this system. QPF will be on
the order of half an inch to an inch. At least several inches of
snowfall if not more seem very likely. This winter storm
potential will need to be watched closely through the weekend for
forecast trends. That storm system will move out of the area
Tuesday night.
Very cold airmass moves in for middle and end of next week with
fresh snow cover expected and high pressure overhead...temperatures
will be very cold and especially overnight lows. Long range models are
still indicating the potential of another significant winter storm
sometime by the end of next week as well. Very active weather
pattern starting this weekend through end of next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday Morning)
Issued at 538 AM CST FRI JAN 31 2014
Pilots can expect deteriorating flight conditions at area
terminals today.
A front will remain stalled along the Interstate corridor through
tonight while moisture increases. Ceilings will lower today and
become prevailing MVFR. Areas of drizzle or freezing drizzle will
impact area terminals.
Precipitation will develop later tonight int Saturday morning as
surface low pressure tracks across the region. Expect IFR ceilings
to increase in coverage tonight and persist into Saturday morning.
Low level wind shear will develop late tonight. Surface winds will
shift to the west and northwest Saturday morning as the low
pressure system and front move to the east.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...WINTER WEATHER ADVISORY until Noon CST Saturday FOR MOZ055>058-
066>071-077>081-088>091-094.
KS...WINTER WEATHER ADVISORY until Noon CST Saturday FOR KSZ073-097-
101.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Foster
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
339 AM CST Fri Jan 31 2014
...Active Weather Pattern Through Next Week...
.SHORT TERM...(Today through Tomorrow)
Issued at 258 AM CST FRI JAN 31 2014
Very tricky forecast over the next 24 to 36 hours due to a surface
front in the area and two waves of precipitation moving through.
Temperatures and precip type is going to be challenging today
through tomorrow with a degree or two making a huge difference if
precip will be frozen or not.
There is a front basically near the I-44 corridor with
temperatures just below freezing north of that front and in the
middle 30s south of that front with the only exception over
towards West Plains where temperatures are actually in the middle
20s due to some localized clear skies. Ceilings are slowly
dropping and radar is starting to show some light echos developing
across southwest Missouri indicating that low level moisture is
beginning to move in.
The initial wave will develop very light precip in the form of
drizzle or freezing drizzle this morning through the afternoon.
The RUC models suggest that areas north of the spine of the Ozark
Plateau will likely stay in the lower 30s today and areas south of
the Plateau across far southern Missouri getting into the lower
40s. There will be a tight temperatures gradient across the CWA today.
Patchy freezing drizzle will be possible this morning for areas
north of I-44 through the early afternoon. Areas along the Highway
54 corridor will remain close to that freezing mark for most of
the day and will have the best potential of seeing either light
freezing rain or freezing drizzle through the afternoon hours.
An area of low pressure will ride up and along the front tonight
along with the main upper level wave moving through tonight. The
low pressure will move from southwest Missouri to east central
Missouri by Saturday morning. The best chance of precipitation
will be across central Missouri and the eastern Ozarks tonight
through tomorrow with lesser pops across the southwest corner of
the state and in southeast Kansas.
Expecting the best potential for freezing rain and sleet mix will
be across the Highway 54 corridor late tonight into tomorrow
morning where about a tenth of an inch of ice will be possible and
a dusting of light sleet or light snow when the precip wraps up
late Saturday morning. Areas along and north of I-44 will have a
window of seeing light freezing rain or light sleet mix perhaps
some light snow to end with tomorrow morning ending from west to
east Saturday afternoon.
Again...a light glaze of ice possible and a dusting of light sleet
or snow. At this time will let the current winter weather advisory
continue because of the threat of patchy freezing drizzle this
morning through early afternoon and then the risk for winter
weather late tonight into early Saturday morning.
.LONG TERM...(Saturday night through Friday)
Issued at 258 AM CST FRI JAN 31 2014
Cold Canadian airmass will settle in for the latter half of the
weekend into early next week. Have followed the ECMWF closely with
the latest trends from Sunday through the end of next week. There
will be an upper level wave moving south of the area Sunday
afternoon. There has been a slight trend to bring some precip
northward into southern Missouri Sunday afternoon. Will mention
light snow possible for extreme southern Missouri with best
chances south of our area. A light dusting may be possible for
areas of far southern Missouri.
The potential is increasing of a significant winter storm will
move in Monday night through Tuesday night. Models are converging
on a solution but still have some minor differences on thermal
profiles and amounts. Snow will begin to develop and move in late
Monday night into Tuesday morning with Tuesday morning through
early afternoon being the prime time for snow and some of it looks
like it could be heavy at times. There maybe some a wintry mix of
sleet and snow for areas over far southern Missouri.
Will start mentioning some decent accumulating snow looks
increasing likely for the Ozarks with this system. QPF will be on
the order of half an inch to an inch. At least several inches of
snowfall if not more seem very likely. This winter storm
potential will need to be watched closely through the weekend for
forecast trends. That storm system will move out of the area
Tuesday night.
Very cold airmass moves in for middle and end of next week with
fresh snow cover expected and high pressure overhead...temperatures
will be very cold and especially overnight lows. Long range models are
still indicating the potential of another significant winter storm
sometime by the end of next week as well. Very active weather
pattern starting this weekend through end of next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1122 PM CST THU JAN 30 2014
Dry lower levels will continue to saturate overnight and on Friday
with lowering ceilings. Precipitation will eventually reach the
ground. Expecting VFR conditions to deteriorate into MVFR towards
daybreak with IFR conditions possibly by late in the day.
Precipitation type could begin as light freezing rain, however
models show freezing line shifting to along the CWA northern edge
during the late morning so should change over to all rain.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...WINTER WEATHER ADVISORY until Noon CST Saturday FOR MOZ055>058-
066>071-077>081-088>091-094.
KS...WINTER WEATHER ADVISORY until Noon CST Saturday FOR KSZ073-097-
101.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Lindenberg
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1137 PM CST Thu Jan 30 2014
.UPDATE:
Issued at 913 PM CST Thu Jan 30 2014
Quick update to adjust POPs overnight based on latest guidance.
Main change was to shift higher POPs further to the S based on
latest RAP trends. The RAP and HRRR suggest a brief, quick shot of
SN late tonight into Fri morning along and just N of I70 as a weak
s/w passes thru the region. These mdls quickly have this area of
precip moving thru the region with forcing diminishing. However,
confidence in precip waning during this period is somewhat low as
lower level forcing shud be increasing during the morning hours.
That said, precip intensity shud be less than what these areas
shud see Fri evening into Sat. With only the 00z NAM in so far,
POPs for Fri afternoon may need to be increased across SE and E
central MO, perhaps into SW IL. However, will allow the next shift
to analyze all of the 00z guidance and latest sat and RADAR trends
and adjust as needed.
Tilly
&&
.SHORT TERM: (Through Late Tonight)
Issued at 344 PM CST Thu Jan 30 2014
The fcst for late this aftn and tonight was in pretty good order
until the Quincy arpt reported snow earlier this aftn. Have had to
increase POPs for late this aftn and early evening and added a few
tenths of an inch of snow. This band should work east thru the
evening and be in e cntrl IL by midnight. This band of precip is due
to frontogenesis assoc with an approaching cold front. The front is
fcst to push thru the CWA overnight and then get hung up across SE
MO and sthrn IL on Friday. A band of WAA snow should begin to move
into NE MO prior to 12Z. There is some question as to how far east
this precip will make it prior to 12Z. Current thinking is it should
make it to at least the MS R with a dusting expected by sunrise. Precip
should be all snow overnight. There could be some -FZDZ in cntrl MO
prior to 12Z...but best chances are later in the mrng.
2%
.LONG TERM: (Friday through Next Thursday)
Issued at 344 PM CST Thu Jan 30 2014
(Friday through Sunday)
This is a messy forecast, with the low to mid level thermal gradient
draped across the area for the entire event. The forecast is likely
to change again as we move through Friday into Friday night and
Saturday.
First wave of wintry precip should begin Friday morning.
Cyclogenesis over the southwest Plains will cause the low level jet
to ramp up over the area. The primary baroclinic zone looks to be
over Oklahoma so the lift will be relatively weak. Forecast
soundings and critical thickness forecasts show there may be a
variety of precip types along and south of the I-70 corridor, but it
should be cold enough for all snow up in northeast Missouri and west
central Illinois. Precipitation up there may be further enhanced by
a pasing vortmax and divergence aloft from the increasing upper
level jet. Areas/patches of very light snow or freezing drizzle
will be likely further south with warming temperatures in the warm
advection turning the precip to a mostly rain or snow mix during the
afternoon.
Low level warm advection continues Friday night, but with increasing
mid and upper level support. Should see precipitation intensity
increase during the evening as a wave forms on the front and
frontogenesis increases over the region. The upper level jet streak
will also continue to increase aiding in lift. Current indications
are that there will be a band of snow across northern portions of
the CWFA as the low level wave travels northeast along the
baroclinic zone. Further south, primarily warm advection precip
will continue Saturday ahead of the front as it oozes south.
Primary concern for areas along and south of I-70 will be a
sleet/freezing rain mix due to the shallow nature of the cold air.
Precipitation should be ending by late Saturday afternoon into
Saturday evening.
Am issuing a winter weather advisory for parts of central Missouri
beginning at 12Z Friday morning and continuing until the precip ends
Saturday afternoon...primarily for the potential of light glazing
with the freezing drizzle, and then the mixed precip Friday night
into Saturday. For northeast Missouri and west central Illinois
will likewise issue an advisory for the snow. Am holding off at
this time for areas further east and south due to the uncertainty of
start times and precip types.
Carney
(Sunday night through Thursday night)
It appears that the precipitation will shift s-se of our forecast
area by Sunday night as a surface ridge builds sewd into the area.
Temperatures will be quite cold, especially across nern MO and w
cntrl IL with the models forecasting 850 mb temperatures of -7 to
-10 C across this area Sunday night. Will see warmer temperatures
Monday and Monday night as the surface/850 mb ridge shifts east of
our area and the surface/low level winds become sely/sly. The next
round of precipitation should spread ewd into at least the wrn
half of our forecast area late Monday ngt as a sly low level jet
brings fairly strong low level waa and increasing moisture into the
region ahead of an approaching upper level trough. Both the ECMWF
and GFS models have precipitation across the entire forecast area on
Tuesday with the 850 mb low tracking newd through sern MO and srn IL
Tuesday aftn and evng, and the surface low moving newd through wrn
portions of TN and KY Tuesday aftn and evng. The models were also
depicting relatively strong upper level divergence on Tuesday over
our area ahead of the approaching upper level trough. The ECMWF
model is a little cooler than the GFS model. The precipitation type
should be all snow north and west of STL, but a mixture of snow,
sleet, freezing rain and rain south and east of STL based on the
850 mb temperature and partial thickness forecasts. The waa, warm
conveyor type precipitation should shift east of our area Tuesday
night with a dry slot moving newd into sern MO and swrn IL, but
deformation zone snow should impact mainly nern MO and w cntrl IL
Tuesday night based on the current forecast track of this winter
storm system. The snow should taper off to flurries on Wednesday as
the upper level trough shifts east of our area, and a strong surface
ridge builds sewd into the region. Although there is still a lot of
uncertainty as to the exact track of the storm system, it currently
appears that the highest snowfall amounts will occur across nern MO
and w cntrl IL, north and west of STL where the precipitation type
will be all snow and the snowfall duration will be the longest due
to the first wave of waa snows late Monday night and Tuesday
followed by the deformation snows Tuesday night. Very cold air will
filter sewd into the region on Wednesday, and this coupled with new
snow on the ground across most of the forecast area will lead to
unseasonably cold temperatures for Wednesday through Thursday
night.
GKS
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1137 PM CST Thu Jan 30 2014
VFR conditions will prevail at the TAF sites thru the remainder of
tonight and for at least much of Friday morning. A cold front is
working its way thru the northwestern STL metro area now and
should be thru all metro TAF sites by around 07z. Some snow is
snaking eastward from Kansas and some of this may edge COU and the
STL metro sites early Friday morning, but probs of it happening
remain lo enough to preclude mention at this time. A much better
chance for pcpn will occur late Friday morning for UIN as broader
scale lift commences north of the now stalled front south of STL
metro. This area of pcpn should expand further south into COU and
STL metro sites by late Friday afternoon and continue at least
intermittently thru much of Friday night. Pcpn-type should
initially be snow for all TAF sites but warm air aloft, and in the
case of STL metro sites, surface temps expected to poke above 32F,
should transition pcpn thru some sleet and eventually settle on
either FZRA or RA. COU looks more favorable for FZRA and went with
just RA for now at the STL metro sites. Deteriorating conditions
can be expected on Friday, especially during the afternoon and
evening, going from VFR to IFR at all sites.
Specifics for KSTL: VFR conditions expected thru at least midday
Friday before deteriorating conditions to IFR, especially by
Friday evening. In the meantime, a cold front will push thru at
the beginning of the period and shift winds out of the NW, and
veering still further to NE by daybreak Friday and E later on
Friday. A small chance for snow exists early Friday morning,
between 12-15z, but probs too lo for mention in TAF. Better
chances of at least intermittent pcpn will be from late Friday
afternoon thru the night. Pcpn-types should start out as frozen SN
and PL, eventually turning to liquid RA as both air aloft and
surface temps rise thru Friday night. The liquid phase for Friday
night looks more favorable for plain rain, but the 32F line will
be lingering not too far off to the northwest, so will be close.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY from 6 AM Friday to 6 PM CST Saturday
FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Gasconade MO-
Knox MO-Lewis MO-Marion MO-Moniteau MO-Monroe MO-Montgomery
MO-Osage MO-Pike MO-Ralls MO-Shelby MO.
IL...WINTER WEATHER ADVISORY from 6 AM Friday to 6 PM CST Saturday
FOR Adams IL-Brown IL-Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1200 PM CST FRI JAN 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 253 AM CST FRI JAN 31 2014
A BAND OF MODERATE TO LOCALLY HEAVY SNOW HAS DEVELOPED ALONG THE
KS-NEB BORDER. THIS BAND WILL LIFT NORTH A BIT THIS MORNING AS IT
TRANSLATES EAST OUT OF THE FCST AREA BY 15Z- 18Z. THE MODELS
APPEAR TO BE TOO FAST WITH THIS EVOLUTION AND MANY SOLNS QUICKLY
DISSOLVE THE FRONTOGENETICALLY FORCED SNOW BAND AS IT MOVES OFF
THE COLO HIGH PLAINS. THE ARF AND NMM MESOSCALE SOLNS ARE THE
BEST PRESERVING THE SNOW BAND BUT STILL DISSOLVE IT ONCE IT
CLEARS MCCOOK.
SO THE WINTER WEATHER ADVISORY FOR 3 TO 5 INCHES STILL LOOKS
PROMISING SOUTH OF INTERSTATE 80. NORTH OF THE INTERSTATE...NORTH
SOUTH ORIENTED SNOW BAND STRUCTURES SUGGEST WINDS ALOFT ARE
STRONG PERHAPS IN RESPONSE TO SOME CSI. THE NAM WINDS SUGGEST
THIS WHILE THE RAP MODEL DOES NOT. ACCORDING TO THE NAM...THE
H700MB WIND SPEED MAX WORKING THROUGH NCNTL NEB SHOULD CONTINUE
UNTIL 15Z AND THEN DECAY. NONETHELESS 1 TO 3 INCHES OF SNOW
SHOULD ACCUMULATE ALONG AND NORTH OF INTERSTATE 80 AS THESE SNOW
BANDS MOVE THROUGH. THE TEXTURE OF THE SNOW WITH THIS EVENTS
APPEARS TO HAVE SOME RIMING AND IS GREASY UNDERFOOT PRODUCING
HAZARDOUS TRAVEL CONDITIONS SO THE WINTER WEATHER ADVISORY WILL
CONTINUE AS FCST.
FOR TONIGHT...ANOTHER DISTURBANCE...CURRENTLY ACROSS SRN
CALIFORNIA IS EXPECTED TO LIFT ACROSS THE ROCKIES AND TRACK A BIT
FARTHER SOUTH OF THE CURRENT DISTURBANCE. A MODEL BLENDED SOLN
PRODUCES A CHANCE OF SNOW ACROSS THE SOUTHEASTERN EDGE OF THE
FCST AREA INCLUDING CUSTER COUNTY. SOME MODEL SOLNS ARE FARTHER
SOUTH AND KEEP THE ACCUMULATING SNOW SOUTH AND EAST OF THE FCST
AREA. IT LOOKS LIKE THE FORCING AND FRONTOGENESIS MAY BE
BIFURCATED ONCE AGAIN AND THE GFS...NAM AND GEM PRODUCE A SECOND
WEAK BAND OF SNOW NORTH OF THE MAIN BAND PASSING THROUGH KS. THE
ECM...SREF AND SOME OF THE ARF/NMM SOLNS DO NOT SHOW THIS
DEVELOPMENT. SO THE SNOW FORECAST FOR TONIGHT IS UNCERTAIN.
MOISTURE REMAINS TRAPPED ALONG THE PERIPHERY OF THE ARCTIC RIDGE
ACROSS MOST OF THE FCST AREA TODAY. THE MODELS SHOW SOME CLEARING
THIS AFTERNOON AND TONIGHT ACROSS THE NORTH AS ANOTHER PORTION OF
THIS HIGH BUILDS SOUTH AND WEST INTO THE FCST AREA. THIS COULD
SET UP RADIATIONAL COOLING CONDITIONS ACROSS THE NORTH TONIGHT SO
THAT PORTION OF THE FCST AREA USES THE COOL MAV GUIDANCE FOR LOWS
IN THE SINGLE DIGITS. OVERCAST SKIES ARE EXPECTED TO CONTINUE
TONIGHT ACROSS THE NEWLY FORMED SNOW FIELD ACROSS THE SOUTH AND
WESTERN PORTIONS OF THE FCST AREA. HIGHS TODAY RISE INTO THE 20S
TODAY WITH WARMEST READINGS ACROSS THE NORTH WHERE LITTLE OR NO
SNOW FELL AND SOME CLEARING IS EXPECTED DURING THE AFTN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 253 AM CST FRI JAN 31 2014
SATURDAY MORNING WILL SEE ONE SYSTEM EXITING TO THE
EAST...HOWEVER THE NEXT CLIPPER TO MOVE IN FROM THE NW. COLD AND
DRY HIGH PRESSURE AT THE SURFACE WILL UNDERCUT THE MID/UPPER
LEVEL DISTURBANCE. THIS BRINGS SOME CONCERN ABOUT
MOISTURE...ESPECIALLY IN THE LOWER LEVELS. MODELS HAVE TRENDED
DRIER FOR THE PLAINS...WITH THE MAJORITY OF THE QPF IN THE HIGHER
TERRAIN...MOUNTAINS AND FRONT RANGE. SO NO REASONS TO DISCOUNT
THIS AS MODELS IN GOOD AGREEMENT...THUS FORECAST KEEPS SLGHT CHC
OF SNOW FOR THE WESTERN ZONES. WITH THE COLD HIGH PRESSURE
ADVECTION SOUTH...EXPECT TEMPS TO STRUGGLE TO WARM. THE USUALLY
WARMER SW HAS BEEN TRENDED COOLER AS THE THIS MORNING SNOWFALL
WILL STILL BE AROUND TO HELP LIMIT WARMING. ONLY KNOCKED A FEW
DEGREES FROM GUIDANCE BLEND...ALTHOUGH THIS MAY BE OPTIMISTIC AND
A TREND DOWN MAY BE NEEDED.
COLD HIGH PRESSURE AND DRY FOR SUNDAY...WITH HIGHS IN THE 20S.
DID CONTINUE TO TREND THE SW DOWN. AS THE HIGH SHIFTS EAST SUNDAY
NIGHT RETURN SW FLOW WILL HELP TO KEEP LOWS A FEW DEGREES WARMER
THAN SAT NIGHT...AND MIGHT SEE WARMING TEMPS TOWARDS
MORNING...SOMETHING TO WATCH FOR OVER THE NEXT FEW RUNS.
BY MONDAY MODELS THE SFC HIGH SHIFTS OVER THE OHIO RVR
VALLEY...MEANWHILE AN UPPER LEVEL TROUGH WILL DIG TOWARDS THE 4
CORNERS. THE COMBINATION OF RETURN SOUTHERLY MOIST FLOW AND THE
UPPER LEVEL LIFT AHEAD OF THE TROUGH AXIS WILL BRING A CHANCE FOR
ADDITIONAL SNOWFALL. THE MODELS FOCUS THE BEST LIFT AND BEST
MOISTURE /AND GREATEST QPF/ FROM SE COLORADO INTO NW IOWA. MIGHT
SEE ACTIVITY DEVELOP AS EARLY AS MONDAY AFTERNOON...HOWEVER
EXPECT THIS WILL BE TIME TO SATURATE WITH MAYBE SOME FLURRIES IF
ANYTHING. EXPECTING THE BETTER DYNAMICS TO COME THROUGH MONDAY
NIGHT INTO TUESDAY WITH THE UPPER LEVEL WAVE.
THE REST OF THE WEEK CONTINUES TO BE DOMINATED WITH A BROAD
TROUGH ACROSS MUCH OF THE CONUS. AS FOR THE HIGH PLAINS EXPECT
COLD AIR...HIGHS GENERALLY IN THE TEENS AND LOWS IN THE SINGLE
DIGITS...AND AN ACTIVE PATTERN. THE NEXT DISTURBANCE/SUBTLE WAVE
TO MOVE ACROSS THE PLAINS TOWARDS THE END OF THE WEEK. LOW POPS
FOR NOW AND WILL MONITOR AS EXPECTING TIMING WILL BE ADJUSTED IN
THE COMING DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1150 AM CST FRI JAN 31 2014
SNOW IS TAPERING OFF ACROSS THE AREA...AND WILL END THIS
AFTERNOON. MOST AREAS SHOULD IMPROVE TO VFR CONDITIONS. WINDS WILL
BE LIGHT. ANOTHER SYSTEM WILL PASS TO OUR SOUTH TONIGHT. SOME LIGHT
SNOW IS POSSIBLE ACROSS SOUTHWEST NEBRASKA ON THE NORTHERN SIDE OF
THE SYSTEM. OTHERWISE WITH PLENTY OF MOISTURE IN THE
ATMOSPHERE...EXPECT MVFR AND PERHAPS LOCAL IFR CEILINGS TO DEVELOP
ACROSS SOUTHWEST NEBRASKA TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ022-056>059-069>071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...TAYLOR
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
533 AM CST FRI JAN 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 253 AM CST FRI JAN 31 2014
A BAND OF MODERATE TO LOCALLY HEAVY SNOW HAS DEVELOPED ALONG THE
KS-NEB BORDER. THIS BAND WILL LIFT NORTH A BIT THIS MORNING AS IT
TRANSLATES EAST OUT OF THE FCST AREA BY 15Z- 18Z. THE MODELS
APPEAR TO BE TOO FAST WITH THIS EVOLUTION AND MANY SOLNS QUICKLY
DISSOLVE THE FRONTOGENETICALLY FORCED SNOW BAND AS IT MOVES OFF
THE COLO HIGH PLAINS. THE ARF AND NMM MESOSCALE SOLNS ARE THE
BEST PRESERVING THE SNOW BAND BUT STILL DISSOLVE IT ONCE IT
CLEARS MCCOOK.
SO THE WINTER WEATHER ADVISORY FOR 3 TO 5 INCHES STILL LOOKS
PROMISING SOUTH OF INTERSTATE 80. NORTH OF THE INTERSTATE...NORTH
SOUTH ORIENTED SNOW BAND STRUCTURES SUGGEST WINDS ALOFT ARE
STRONG PERHAPS IN RESPONSE TO SOME CSI. THE NAM WINDS SUGGEST
THIS WHILE THE RAP MODEL DOES NOT. ACCORDING TO THE NAM...THE
H700MB WIND SPEED MAX WORKING THROUGH NCNTL NEB SHOULD CONTINUE
UNTIL 15Z AND THEN DECAY. NONETHELESS 1 TO 3 INCHES OF SNOW
SHOULD ACCUMULATE ALONG AND NORTH OF INTERSTATE 80 AS THESE SNOW
BANDS MOVE THROUGH. THE TEXTURE OF THE SNOW WITH THIS EVENTS
APPEARS TO HAVE SOME RIMING AND IS GREASY UNDERFOOT PRODUCING
HAZARDOUS TRAVEL CONDITIONS SO THE WINTER WEATHER ADVISORY WILL
CONTINUE AS FCST.
FOR TONIGHT...ANOTHER DISTURBANCE...CURRENTLY ACROSS SRN
CALIFORNIA IS EXPECTED TO LIFT ACROSS THE ROCKIES AND TRACK A BIT
FARTHER SOUTH OF THE CURRENT DISTURBANCE. A MODEL BLENDED SOLN
PRODUCES A CHANCE OF SNOW ACROSS THE SOUTHEASTERN EDGE OF THE
FCST AREA INCLUDING CUSTER COUNTY. SOME MODEL SOLNS ARE FARTHER
SOUTH AND KEEP THE ACCUMULATING SNOW SOUTH AND EAST OF THE FCST
AREA. IT LOOKS LIKE THE FORCING AND FRONTOGENESIS MAY BE
BIFURCATED ONCE AGAIN AND THE GFS...NAM AND GEM PRODUCE A SECOND
WEAK BAND OF SNOW NORTH OF THE MAIN BAND PASSING THROUGH KS. THE
ECM...SREF AND SOME OF THE ARF/NMM SOLNS DO NOT SHOW THIS
DEVELOPMENT. SO THE SNOW FORECAST FOR TONIGHT IS UNCERTAIN.
MOISTURE REMAINS TRAPPED ALONG THE PERIPHERY OF THE ARCTIC RIDGE
ACROSS MOST OF THE FCST AREA TODAY. THE MODELS SHOW SOME CLEARING
THIS AFTERNOON AND TONIGHT ACROSS THE NORTH AS ANOTHER PORTION OF
THIS HIGH BUILDS SOUTH AND WEST INTO THE FCST AREA. THIS COULD
SET UP RADIATIONAL COOLING CONDITIONS ACROSS THE NORTH TONIGHT SO
THAT PORTION OF THE FCST AREA USES THE COOL MAV GUIDANCE FOR LOWS
IN THE SINGLE DIGITS. OVERCAST SKIES ARE EXPECTED TO CONTINUE
TONIGHT ACROSS THE NEWLY FORMED SNOW FIELD ACROSS THE SOUTH AND
WESTERN PORTIONS OF THE FCST AREA. HIGHS TODAY RISE INTO THE 20S
TODAY WITH WARMEST READINGS ACROSS THE NORTH WHERE LITTLE OR NO
SNOW FELL AND SOME CLEARING IS EXPECTED DURING THE AFTN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 253 AM CST FRI JAN 31 2014
SATURDAY MORNING WILL SEE ONE SYSTEM EXITING TO THE
EAST...HOWEVER THE NEXT CLIPPER TO MOVE IN FROM THE NW. COLD AND
DRY HIGH PRESSURE AT THE SURFACE WILL UNDERCUT THE MID/UPPER
LEVEL DISTURBANCE. THIS BRINGS SOME CONCERN ABOUT
MOISTURE...ESPECIALLY IN THE LOWER LEVELS. MODELS HAVE TRENDED
DRIER FOR THE PLAINS...WITH THE MAJORITY OF THE QPF IN THE HIGHER
TERRAIN...MOUNTAINS AND FRONT RANGE. SO NO REASONS TO DISCOUNT
THIS AS MODELS IN GOOD AGREEMENT...THUS FORECAST KEEPS SLGHT CHC
OF SNOW FOR THE WESTERN ZONES. WITH THE COLD HIGH PRESSURE
ADVECTION SOUTH...EXPECT TEMPS TO STRUGGLE TO WARM. THE USUALLY
WARMER SW HAS BEEN TRENDED COOLER AS THE THIS MORNING SNOWFALL
WILL STILL BE AROUND TO HELP LIMIT WARMING. ONLY KNOCKED A FEW
DEGREES FROM GUIDANCE BLEND...ALTHOUGH THIS MAY BE OPTIMISTIC AND
A TREND DOWN MAY BE NEEDED.
COLD HIGH PRESSURE AND DRY FOR SUNDAY...WITH HIGHS IN THE 20S.
DID CONTINUE TO TREND THE SW DOWN. AS THE HIGH SHIFTS EAST SUNDAY
NIGHT RETURN SW FLOW WILL HELP TO KEEP LOWS A FEW DEGREES WARMER
THAN SAT NIGHT...AND MIGHT SEE WARMING TEMPS TOWARDS
MORNING...SOMETHING TO WATCH FOR OVER THE NEXT FEW RUNS.
BY MONDAY MODELS THE SFC HIGH SHIFTS OVER THE OHIO RVR
VALLEY...MEANWHILE AN UPPER LEVEL TROUGH WILL DIG TOWARDS THE 4
CORNERS. THE COMBINATION OF RETURN SOUTHERLY MOIST FLOW AND THE
UPPER LEVEL LIFT AHEAD OF THE TROUGH AXIS WILL BRING A CHANCE FOR
ADDITIONAL SNOWFALL. THE MODELS FOCUS THE BEST LIFT AND BEST
MOISTURE /AND GREATEST QPF/ FROM SE COLORADO INTO NW IOWA. MIGHT
SEE ACTIVITY DEVELOP AS EARLY AS MONDAY AFTERNOON...HOWEVER
EXPECT THIS WILL BE TIME TO SATURATE WITH MAYBE SOME FLURRIES IF
ANYTHING. EXPECTING THE BETTER DYNAMICS TO COME THROUGH MONDAY
NIGHT INTO TUESDAY WITH THE UPPER LEVEL WAVE.
THE REST OF THE WEEK CONTINUES TO BE DOMINATED WITH A BROAD
TROUGH ACROSS MUCH OF THE CONUS. AS FOR THE HIGH PLAINS EXPECT
COLD AIR...HIGHS GENERALLY IN THE TEENS AND LOWS IN THE SINGLE
DIGITS...AND AN ACTIVE PATTERN. THE NEXT DISTURBANCE/SUBTLE WAVE
TO MOVE ACROSS THE PLAINS TOWARDS THE END OF THE WEEK. LOW POPS
FOR NOW AND WILL MONITOR AS EXPECTING TIMING WILL BE ADJUSTED IN
THE COMING DAYS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 533 AM CST FRI JAN 31 2014
MVFR/IFR CIGS AND VSBY WILL BE WIDESPREAD SOUTH OF NEBRASKA
HIGHWAY 2 THIS MORNING.
CIGS AND VSBY IMPROVE TO MVFR/VFR AFTER 18Z WITH THE EXIT OF THE
STORM SYSTEM ONGOING ACROSS THE FCST AREA THIS MORNING.
THEN...ANOTHER SYSTEM BRUSHES THE SOUTH TONIGHT WITH MVFR/IFR
CIGS AND VSBY IN SNOW. THIS IS A FAIRLY MINOR AS THE SYSTEM MOVES
SOUTH OF THE FCST AREA. STILL...MVFR CIGS SHOULD CONTINUE TONIGHT
ALONG OR SOUTH OF NEBRASKA HIGHWAY 2 WITH THE TRAPPED MOISTURE
BENEATH THE WRN PERIPHERY OF THE ARCTIC RIDGE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM CST /8 AM MST/ THIS MORNING
FOR NEZ022-056>059-069>071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
253 AM CST FRI JAN 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 253 AM CST FRI JAN 31 2014
A BAND OF MODERATE TO LOCALLY HEAVY SNOW HAS DEVELOPED ALONG THE
KS-NEB BORDER. THIS BAND WILL LIFT NORTH A BIT THIS MORNING AS IT
TRANSLATES EAST OUT OF THE FCST AREA BY 15Z- 18Z. THE MODELS
APPEAR TO BE TOO FAST WITH THIS EVOLUTION AND MANY SOLNS QUICKLY
DISSOLVE THE FRONTOGENETICALLY FORCED SNOW BAND AS IT MOVES OFF
THE COLO HIGH PLAINS. THE ARF AND NMM MESOSCALE SOLNS ARE THE
BEST PRESERVING THE SNOW BAND BUT STILL DISSOLVE IT ONCE IT
CLEARS MCCOOK.
SO THE WINTER WEATHER ADVISORY FOR 3 TO 5 INCHES STILL LOOKS
PROMISING SOUTH OF INTERSTATE 80. NORTH OF THE INTERSTATE...NORTH
SOUTH ORIENTED SNOW BAND STRUCTURES SUGGEST WINDS ALOFT ARE
STRONG PERHAPS IN RESPONSE TO SOME CSI. THE NAM WINDS SUGGEST
THIS WHILE THE RAP MODEL DOES NOT. ACCORDING TO THE NAM...THE
H700MB WIND SPEED MAX WORKING THROUGH NCNTL NEB SHOULD CONTINUE
UNTIL 15Z AND THEN DECAY. NONETHELESS 1 TO 3 INCHES OF SNOW
SHOULD ACCUMULATE ALONG AND NORTH OF INTERSTATE 80 AS THESE SNOW
BANDS MOVE THROUGH. THE TEXTURE OF THE SNOW WITH THIS EVENTS
APPEARS TO HAVE SOME RIMING AND IS GREASY UNDERFOOT PRODUCING
HAZARDOUS TRAVEL CONDITIONS SO THE WINTER WEATHER ADVISORY WILL
CONTINUE AS FCST.
FOR TONIGHT...ANOTHER DISTURBANCE...CURRENTLY ACROSS SRN
CALIFORNIA IS EXPECTED TO LIFT ACROSS THE ROCKIES AND TRACK A BIT
FARTHER SOUTH OF THE CURRENT DISTURBANCE. A MODEL BLENDED SOLN
PRODUCES A CHANCE OF SNOW ACROSS THE SOUTHEASTERN EDGE OF THE
FCST AREA INCLUDING CUSTER COUNTY. SOME MODEL SOLNS ARE FARTHER
SOUTH AND KEEP THE ACCUMULATING SNOW SOUTH AND EAST OF THE FCST
AREA. IT LOOKS LIKE THE FORCING AND FRONTOGENESIS MAY BE
BIFURCATED ONCE AGAIN AND THE GFS...NAM AND GEM PRODUCE A SECOND
WEAK BAND OF SNOW NORTH OF THE MAIN BAND PASSING THROUGH KS. THE
ECM...SREF AND SOME OF THE ARF/NMM SOLNS DO NOT SHOW THIS
DEVELOPMENT. SO THE SNOW FORECAST FOR TONIGHT IS UNCERTAIN.
MOISTURE REMAINS TRAPPED ALONG THE PERIPHERY OF THE ARCTIC RIDGE
ACROSS MOST OF THE FCST AREA TODAY. THE MODELS SHOW SOME CLEARING
THIS AFTERNOON AND TONIGHT ACROSS THE NORTH AS ANOTHER PORTION OF
THIS HIGH BUILDS SOUTH AND WEST INTO THE FCST AREA. THIS COULD
SET UP RADIATIONAL COOLING CONDITIONS ACROSS THE NORTH TONIGHT SO
THAT PORTION OF THE FCST AREA USES THE COOL MAV GUIDANCE FOR LOWS
IN THE SINGLE DIGITS. OVERCAST SKIES ARE EXPECTED TO CONTINUE
TONIGHT ACROSS THE NEWLY FORMED SNOW FIELD ACROSS THE SOUTH AND
WESTERN PORTIONS OF THE FCST AREA. HIGHS TODAY RISE INTO THE 20S
TODAY WITH WARMEST READINGS ACROSS THE NORTH WHERE LITTLE OR NO
SNOW FELL AND SOME CLEARING IS EXPECTED DURING THE AFTN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 253 AM CST FRI JAN 31 2014
SATURDAY MORNING WILL SEE ONE SYSTEM EXITING TO THE
EAST...HOWEVER THE NEXT CLIPPER TO MOVE IN FROM THE NW. COLD AND
DRY HIGH PRESSURE AT THE SURFACE WILL UNDERCUT THE MID/UPPER
LEVEL DISTURBANCE. THIS BRINGS SOME CONCERN ABOUT
MOISTURE...ESPECIALLY IN THE LOWER LEVELS. MODELS HAVE TRENDED
DRIER FOR THE PLAINS...WITH THE MAJORITY OF THE QPF IN THE HIGHER
TERRAIN...MOUNTAINS AND FRONT RANGE. SO NO REASONS TO DISCOUNT
THIS AS MODELS IN GOOD AGREEMENT...THUS FORECAST KEEPS SLGHT CHC
OF SNOW FOR THE WESTERN ZONES. WITH THE COLD HIGH PRESSURE
ADVECTION SOUTH...EXPECT TEMPS TO STRUGGLE TO WARM. THE USUALLY
WARMER SW HAS BEEN TRENDED COOLER AS THE THIS MORNING SNOWFALL
WILL STILL BE AROUND TO HELP LIMIT WARMING. ONLY KNOCKED A FEW
DEGREES FROM GUIDANCE BLEND...ALTHOUGH THIS MAY BE OPTIMISTIC AND
A TREND DOWN MAY BE NEEDED.
COLD HIGH PRESSURE AND DRY FOR SUNDAY...WITH HIGHS IN THE 20S.
DID CONTINUE TO TREND THE SW DOWN. AS THE HIGH SHIFTS EAST SUNDAY
NIGHT RETURN SW FLOW WILL HELP TO KEEP LOWS A FEW DEGREES WARMER
THAN SAT NIGHT...AND MIGHT SEE WARMING TEMPS TOWARDS
MORNING...SOMETHING TO WATCH FOR OVER THE NEXT FEW RUNS.
BY MONDAY MODELS THE SFC HIGH SHIFTS OVER THE OHIO RVR
VALLEY...MEANWHILE AN UPPER LEVEL TROUGH WILL DIG TOWARDS THE 4
CORNERS. THE COMBINATION OF RETURN SOUTHERLY MOIST FLOW AND THE
UPPER LEVEL LIFT AHEAD OF THE TROUGH AXIS WILL BRING A CHANCE FOR
ADDITIONAL SNOWFALL. THE MODELS FOCUS THE BEST LIFT AND BEST
MOISTURE /AND GREATEST QPF/ FROM SE COLORADO INTO NW IOWA. MIGHT
SEE ACTIVITY DEVELOP AS EARLY AS MONDAY AFTERNOON...HOWEVER
EXPECT THIS WILL BE TIME TO SATURATE WITH MAYBE SOME FLURRIES IF
ANYTHING. EXPECTING THE BETTER DYNAMICS TO COME THROUGH MONDAY
NIGHT INTO TUESDAY WITH THE UPPER LEVEL WAVE.
THE REST OF THE WEEK CONTINUES TO BE DOMINATED WITH A BROAD
TROUGH ACROSS MUCH OF THE CONUS. AS FOR THE HIGH PLAINS EXPECT
COLD AIR...HIGHS GENERALLY IN THE TEENS AND LOWS IN THE SINGLE
DIGITS...AND AN ACTIVE PATTERN. THE NEXT DISTURBANCE/SUBTLE WAVE
TO MOVE ACROSS THE PLAINS TOWARDS THE END OF THE WEEK. LOW POPS
FOR NOW AND WILL MONITOR AS EXPECTING TIMING WILL BE ADJUSTED IN
THE COMING DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM CST THU JAN 30 2014
SNOW IN SOUTHWEST NEBRASKA WILL REDUCE VISIBILITY TO 1SM OR LOWER
THROUGH TONIGHT AND...EVENTUALLY...CEILING IS LIKELY TO BE LESS
THAN 1000 FEET AGL. METEOROLOGICAL CONDITIONS CAN BE EXPECTED TO
IMPROVE IN SOUTHWEST NEBRASKA BY 15Z. AREAS OF LIGHT SNOW COULD
CONTINUE INTO FRIDAY EVENING AFTER 00Z SOUTH AND EAST OF A BBW-
LBF-OGA LINE.
FOR CENTRAL AND NORTH CENTRAL NEBRASKA...THE PROBABILITY OF
INSTRUMENT METEOROLOGICAL CONDITIONS IS NOT HIGH. STILL SOME
LIGHT SNOW IS EXPECTED 12-18Z WITH VISIBILITY GENERALLY 2-3SM AND
CEILING 1000-1500 FEET AGL.
SNOW ACCUMULATIONS OF FIVE INCHES CAN BE EXPECTED AT IML WITH
THREE TO FOUR INCHES AT LBF AND OGA. OTHER AIRPORTS IN CENTRAL
AND WESTERN NEBRASKA WILL NOT HAVE MAJOR SNOW ACCUMULATION.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM CST /8 AM MST/ THIS MORNING
FOR NEZ022-056>059-069>071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1130 PM CST THU JAN 30 2014
.UPDATE...
ISSUED AT 903 PM CST THU JAN 30 2014
00Z UPPER AIR ANALYSIS INDICATED A GENERAL ZONAL FLOW ALOFT. ONE
JET SEGMENT WAS MOVING EAST OF THE REGION...WHILE ANOTHER UPPER
WAVE WAS MOVING OUT OF THE CENTRAL ROCKIES. THIS WAVE HAD 40 TO 90
METER HEIGHT FALLS. LOW PRESSURE ACROSS SE COLORADO...AND THE
CYCLONIC FLOW ASSOCIATED WITH THAT...COMBINED WITH THE UPPER
LEVEL DIVERGENCE FROM THE EXITING WAVE HAD ALLOWED SNOW TO DEVELOP
ACROSS THE WESTERN HIGH PLAINS GENERALLY BETWEEN I70 AND I80.
MEANWHILE...FURTHER EAST ACROSS THE MID MISSOURI VALLEY...DRY HIGH
PRESSURE PREVAILED WITH A PERSISTENT NORTHERLY FLOW WITH DEWPOINTS
IN THE SINGLE DIGITS. WHILE UPPER AIR ANALYSIS REVEALED MOISTURE
AT H85...IT REMAINS QUITE DRY ABOVE THAT. IT`S THIS DRY AIR THAT
WILL LIMIT THE NORTHWARD EXTENT OF SNOW OVERNIGHT. RECENT RUNS OF
THE RAP DO TRY TO TO DEVELOP THE NORTHERN EDGE OF THE SNOW...WHICH
IS CURRENTLY ACROSS THE NEBRASKA PANHANDLE EAST SOUTHEAST...BUT
LOSING A FIGHTING BATTLE AGAINST THE DRY NORTHERLY FLOW. BELIEVE
THE HEAVIER SNOW ALONG THE SOUTHWESTERN NE/KS BORDER REGION HAS A
BETTER CHANCE OF MOVING EAST INTO SOUTHEAST NEBRASKA OVERNIGHT AND
LINGER THROUGH FRIDAY MORNING WITH SOME MINOR ACCUMULATIONS
POSSIBLE. NEW 00Z NAM ALSO SUPPORTS THIS TREND WITH BEST POPS
POSSIBLE ALONG/SOUTH OF A LINE FROM COLUMBUS TO NEBRASKA CITY TO
RED OAK IOWA WHERE LIKELY TO CATEGORICAL SNOW WILL BE POSSIBLE...
TAPERING TO JUST A CHANCE OF SNOW FURTHER NORTH FROM NORFOLK EAST
SOUTHEAST TO OMAHA...AND NOTHING FURTHER NORTH OF THAT.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 308 PM CST THU JAN 30 2014
EARLY AFTERNOON WATER VAPOR IMAGERY INDICATED A POTENT COMPACT
SHORTWAVE TROUGH OVER CNTRL CA. THIS WAVE WAS ASSOCIATED WITH A
120 KT H25 JET AND A 110 M H5 HEIGHT FALL AT KOAK. THIS SYSTEM IS
EXPECTED TO TAKE A TRACK EWD THIS EVENING...AND MOVE INTO THE
CENTRAL PLAINS WHILE WEAKENING ON FRIDAY. LEAD SHORT WAVE
THROUGH...NOW OVER WI HAS ALLOWED FOR A STRONG MID LEVEL THERMAL
GRADIENT TO DEVELOP OVER THE CNTRL PLAINS WITH +4 C AT KDDC TO -12
C AT KABR. THIS SHORTWAVE TROUGH WILL INCREASE THE FLOW INTO THIS
GRADIENT AND CREATE AN AREA OF MID LEVEL FRONTOGENESIS OVERNIGHT.
THIS WILL INITIALLY OCCUR OVER SOUTHWEST NEB/NW KS THIS EVENING.
CROSS SECTIONAL ANALYSIS INDICATE FAIRLY WEAK STATIC STABILITY IN
THIS AREA WITH THETA-E LAPSE RATES AROUND 1-2. THIS FRONTAL BAND
WILL LIFT NEWD LATE TONIGHT AND INTO THE DAY ON FRIDAY...BUT THIS
BAND WILL BE MOVING INTO AN INCREASINGLY STABLE ATMOSPHERE OVER
EASTERN NEB/WESTERN IA. THIS ALONG WITH A WEAKENING LARGE-SCALE
FORCING FOR ASCENT SHOULD LEAD TO A WEAKENING FRONTAL BAND AS IT
MOVES INTO OUR CWA LATE TONIGHT. HAVE SLOWED THE ONSET OF POPS FOR
MOST OF THE CWA WITH SOME LIGHT SNOW POSSIBLY REACHING OMA BY DAY
BREAK...BUT LIKELY SHORTLY AFTER THAT. THE NORTHERN EXTENT TO THE
PRECIP WILL BE LIMITED BY THE DRY AIR ADVECTION FROM THE
NORTHEAST...BUT ALONG AND SOUTH OF I-80 SHOULD SEE SOME -SN
THROUGH THE MORNING AND INTO THE AFTN.
WE STILL GENERALLY EXPECT A BREAK IN PRECIP FROM MID TO LATE
AFTERNOON AND THROUGH ABOUT 06Z SAT AS THIS SECOND SHORTWAVE
TROUGH SHIFTS EAST...AND BEFORE FORCING FROM THE NEXT WAVE MOVES
INTO THE REGION. THIS SYSTEM APPEARS A BIT BETTER ORGANIZED ON
GLOBAL MODELS AND WE STRONGLY PREFER THE GFS/EC/GEM OVER THE
WEAKER MORE SUPPRESSED NAM. THIS SYSTEM WILL AGAIN ACT TO INCREASE
THE MID LEVEL FRONTOGENESIS IN THE CENTRAL AND SOUTHERN CWA AFTER
MIDNIGHT FRIDAY AND THROUGH THE FIRST HALF OF THE DAY ON SATURDAY.
MODELS INDICATE A BIT BETTER UVV WITH THIS SYSTEM AND THIS SEEMS
REASONABLE GIVEN THE WEAKER STABILITY INDICATED ABOVE THE FRONTAL
SURFACE WITH THETA-E LAPSE RATES EVEN NEGATIVE JUST SOUTH OF THE
KS/NEB BORDER. DRY AIR SHOULD ALSO HAVE LESS OF A NEGATIVE EFFECT
DURING THIS SYSTEM AND THE GFS/EC INDICATE AROUND 3-4 G/KG OF
SPECIFIC HUMIDITY TO WORK WITH FRI NIGHT. COBB OUTPUT AND THERMAL
PROFILES FROM SOUNDINGS INDICATE SNOW RATIOS WILL BE NEAR AVERAGE
FOR OUR NECK OF THE WOODS OF 11-13. THUS WE FEEL 1-3 INCHES ARE
LIKELY ALONG I-80 AND 2-4 IN THE FAR SOUTH SEEMS REASONABLE WITH
LESS AMOUNTS...GENERALLY UNDER AND INCH IN THE NORTH.
WINDS ARE NOT EXPECTED TO BE AN ISSUE WITH THIS SYSTEM WITH LIGHT
WINDS DURING THE TIME OF SNOWFALL. WINDS WILL BEGIN TO INCREASE
DURING THE DAY ON SAT THOUGH AS A COLD FRONT MOVES THROUGH DURING
THE DAY. WITHOUT FALLING SNOW THE WINDS DO NOT APPEAR LIKELY TO
CAUSE MANY ISSUES...BUT WE WILL SEE COLDER TEMPERATURES FOR SAT
NIGHT. HAVE LOWERED GOING LOWS...BUT ACTUAL LOWS WILL DEPEND ON IF
SKIES ARE CLEAR UNDER THE SURFACE HIGH OR NOT WITH SOME TEMPS
BELOW ZERO POSSIBLE IN WESTERN IA.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 308 PM CST THU JAN 30 2014
MAIN FORECAST CHALLENGE IN THE EXTENDED PERIODS WILL BE POTENTIAL
FOR SIGNIFICANT SNOWFALL MONDAY NIGHT INTO TUESDAY.
SOMEWHAT OF A SPLIT FLOW UPPER LEVEL PATTERN WILL BE UNDERWAY AT THE
BEGINNING OF THE PERIOD. A TROUGH IS FORECAST TO BE DIGGING ACROSS
THE PACIFIC AND INTO SOUTHERN CALIFORNIA WHILE A LOW PRESSURE CENTER
SPINS OVER HUDSON`S BAY. THE SOUTHERN TROUGH IS PROGGED TO SLIDE
EAST INTO THE FOUR CORNERS REGION BY MONDAY NIGHT...WITH A LEAD
SHORTWAVE TROUGH MOVING INTO THE CENTRAL PLAINS. IN
ADDITION...MEDIUM RANGE FORECAST MODELS INDICATE A COUPLED JET
STRUCTURE OVER OUR REGION TO SUPPORT LARGE SCALE VERTICAL MOTION.
SOUTHERLY LOW LEVEL FLOW FROM THE GULF NORTH THROUGH THE CENTRAL
PLAINS SHOULD BRING FAIRLY DECENT MOISTURE INTO THE SYSTEM. WITH
CONTINUED UPPER SUPPORT INTO TUESDAY AS THE TROUGH APPROACHES...WE
SHOULD SEE ACCUMULATING SNOW OVER MUCH OF THE FORECAST AREA. MANY
DETAILS HAVE YET TO BE WORKED OUT AS THIS SYSTEM STILL REMAINS OUT
IN THE PACIFIC OCEAN WELL SOUTH OF ALASKA. THIS SYSTEM DOES LOOK
LIKE IT HAS THE POTENTIAL FOR SIGNIFICANT ACCUMULATING SNOW AS LONG
AS DRIER AIR TO THE NORTH DOESN`T WIN. A TIGHTENING SFC GRADIENT
COULD CAUSE SOME BLOWING SNOW ISSUES TUESDAY NIGHT AS A 1040MB HIGH
BUILDS SOUTH INTO THE DAKOTAS. WITH THIS COLD HIGH PRESSURE MOVING
IN AND FRESH SNOW COVER...HAVE LOWERED TEMPS WEDNESDAY AND
THURSDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1130 PM CST THU JAN 30 2014
SNOW CHANCES ARE THE PRIMARY CONCERN WITH TWO WEATHER SYSTEMS
AFFECTING TAF SITES DURING THE PERIOD. FIRST BATCH OF SNOW WAS
TRYING TO MOVE INTO THE AREA...BUT DRY AIR HAS LIMITED EASTWARD
EXTENT. CLOUD BASES HAVE DROPPED TO 8000-10000 FEET...AND WITH
ADDITIONAL SATURATION...COULD SEE SCATTERED FLURRIES WHEN CLOUD
BASES DROP TO 5000 FEET OR LESS...AND VISIBILITY RESTRICTION SNOW
ONCE CEILINGS REACH MVFR. SNOW SHOULD BECOME PREVAILING AT
KLNK...WITH TEMPORARY CONDITIONS AT KOMA...BUT HAVE DOUBTS THAT IT
MAY MAKE IT TO KOFK. THERE WILL BE A BREAK IN BETWEEN SYSTEMS...BUT
SNOW SHOULD REDEVELOP AT TAF SITES TOWARD THE END OF THE PERIOD BY
01/03-06Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...KERN
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS ELKO NV
1058 AM PST FRI JAN 31 2014
.SYNOPSIS...SCATTERED TO NUMEROUS SNOW SHOWERS ARE ON TAP FOR
EASTERN NEVADA TODAY. DRY AND CONTINUED COLD CAN BE EXPECTED OVER
THE WEEKEND WITH ANOTHER WEAK SYSTEM POSSIBLE LATE SUNDAY NIGHT
INTO MONDAY. THIS WILL BRING ANOTHER SHOT OF LIGHT SNOW SHOWERS TO
THE FORECAST AREA.
&&
.UPDATE...SNOW HAS TAPERED OFF TO SCATTERED LIGHT SNOW SHOWERS
OVER NORTHERN LANDER AND NORTHERN EUREKA COUNTIES AT THIS TIME AS
SHORT WAVE MOVES TO THE SOUTHEAST SO HAVE CANCELED THE WINTER
WEATHER ADVISORY FOR THAT AREA.
&&
.PREV DISCUSSION... /ISSUED AT 848 AM /
SYNOPSIS...SCATTERED TO NUMEROUS SNOW SHOWERS ARE ON TAP FOR
EASTERN NEVADA TODAY. DRY AND CONTINUED COLD CAN BE EXPECTED OVER
THE WEEKEND WITH ANOTHER WEAK SYSTEM POSSIBLE LATE SUNDAY NIGHT
INTO MONDAY. THIS WILL BRING ANOTHER SHOT OF LIGHT SNOW SHOWERS TO
THE FORECAST AREA.
UPDATE...RADAR SHOWING AN AREA OF LIGHT SNOW OVER NORTHERN LANDER
AND NORTHERN EUREKA COUNTIES AT THIS TIME ASSOCIATED WITH SHORT
WAVE MOVING THROUGH THE AREA. AS THIS SHORT WAVE MOVES TOWARDS THE
SOUTHEAST IT WILL BRING WIDESPREAD LIGHT SNOW TO EAST CENTRAL NV
LATE THIS MORNING AND AFTERNOON. HAVE UPDATED FORECASTS TO REFLECT
THIS. VALLEYS ACROSS WHITE PINE COUNTY AND SOUTHERN EUREKA COUNTY
COULD SEE UP TO AN INCH OF SNOW OUT OF THIS SYSTEM TODAY. ALSO
LOWER HIGH TEMPS TODAY. WITH 700 MB TEMPS OF -12C TO -14C MANY
AREAS WILL BE HARD PRESSED TO GET ABOVE THE MID 30S.
PREV DISCUSSION... /ISSUED AT 641 AM /
SYNOPSIS...ISOLATED TO SCATTERED LIGHT SNOW SHOWERS ARE ON TAP
FOR TODAY AS A WEAK UPPER SYSTEM PUSHES ACROSS NORTHERN NEVADA.
DRY AND CONTINUED COOL CAN BE EXPECTED OVER THE WEEKEND WITH
ANOTHER WEAK SYSTEM POSSIBLE LATE SUNDAY NIGHT INTO MONDAY. THIS
WILL BRING ANOTHER SHOT OF LIGHT SNOW SHOWERS TO THE FORECAST
AREA.
UPDATE...UPDATED CURRENT GRIDS TO REFLECT ONGOING WEATHER IN
NORTHERN LANDER/EUREKA COUNTIES. PERSISTANT AREA OF LIGHT SNOW
CONTINUES TO FALL IN THIS AREA...WHICH INCLUDES THE I-80 CORRIDOR.
THIS IS IN RESPONSE TO AN UPPER TROUGH APPROACHING FROM THE WEST.
EXPECT THE AREA TO CONTINUE THROUGH THE MORNING BASED ON LATEST
HRRR MODEL RUNS. ALL GRIDS HAVE BEEN UPDATED.
PREV DISCUSSION... /ISSUED AT 338 AM /
SHORT TERM...TODAY THROUGH SUNDAY. RADAR THIS MORNING IS
DEPICTING ISOLATED TO SCATTERED SNOW SHOWERS ACROSS PORTIONS OF
HUMBOLDT AND NORTHERN LANDER/EUREKA COUNTIES. THE REMOTE SITE IN
WINNEMUCCA IS NOW SHOWING A VISIBILITY OF 4 MILES...AND HAS BEEN
IMPROVING. COOP OBSERVER IN WINNEMUCCA REPORTED A QUICK 0.8 INCHES
WITH THE MIDNIGHT OBSERVATION. RUC13 IS SHOWING A BROAD SWATH OF
WEAK LIFT IN THE AREA OF LIGHT PRECIPITATION...AND OUT AHEAD OF
THE 500 MB TROUGH.
MODELS THIS MORNING ARE SHOWING A 500 MB TROUGH AXIS WEST OF
NEVADA. THIS FEATURE WILL BE CROSSING THE FORECAST AREA
TODAY. THE 3KM HRRR IS SHOWING LIGHT SNOW SHOWERS BREAKING OUT
FROM NORTHERN LANDER/EUREKA INTO ELKO COUNTY. HAVE INCREASED POPS
DURING THE MORNING AND VERY EARLY AFTERNOON HOURS IN THE NORTHERN
AND CENTRAL PARTS OF NEVADA. ANOTHER PIECE OF ENERGY WILL DIP
SOUTH AND WEST OF THE REGION...GOING THROUGH CALIFORNIA AND THEN
ARIZONA...WITH THE LAST REMNANTS OF THE UPPER LOW EXITING EARLY
SATURDAY. FOR TODAY EXPECT THE TROUGH WITH TH 500 MB COLD POOL TO
MOVE ACROSS THE AREA. SUFFICIENT INSTABILITY EXISTS TO ALLOW
SCATTERED SHOWERS TO FORM THIS AFTERNOON. THESE SHOWERS COULD DROP
A QUICK HALF INCH TO INCH DEPENDING ON WHERE THEY FORM...ALONG
WITH SUDDEN DROPS IN VISIBILITY.
THE FIRST TROUGH WILL PUSH THROUGH LATER THIS AFTERNOON AND
TONIGHT...WITH THE SECOND PIECE OF ENERGY...AS MENTIONED
EARLIER...PUSHING FURTHER SOUTH. SNOW SHOWERS WILL END WEST TO
EAST BY SATURDAY AFTERNOON...WITH A WEAK SHORTWAVE RIDGE TRYING TO
PUSH ACROSS SATURDAY NIGHT INTO SUNDAY. GFS IS A LITTLE STRONG
WITH ENERGY PUSHING IN FROM THE NORTHWEST. AT THIS TIME...THIS
APPEARS DRY AND SO WILL CONTINUE WITH QUIET CONDITIONS DURING THE
SUNDAY AFTERNOON PERIOD.
LONG TERM...SUNDAY NIGHT THROUGH NEXT THURSDAY. MODELS IS GOOD
AGREEMENT THROUGH TUESDAY WITH NORTHWESTERLY FLOW PATTERN AND
SHORTWAVE PUSHING THROUGH AREA MONDAY...BUT SLIGHTLY OUT OF PHASE BY
WEDNESDAY AND THURSDAY WITH DEVELOPING TROUGH TO NORTHWEST BY END OF
PERIOD.
SUNDAY NIGHT THROUGH TUESDAY. A CLIPPER TYPE SHORTWAVE WILL MOVE
ACROSS THE REGION MONDAY THROUGH TUESDAY MORNING BRINGING A DECENT
SHOT OF SNOW...THUS INCREASED CLOUDS AND POPS FOR THIS TIME FRAME.
EC SLIGHTLY DEEPER AND COLDER WITH THIS SYSTEM BUT OVERALL MODELS ARE
COMING INTO BETTER AGREEMENT AND CONFIDENCE IS INCREASING WITH THIS
SYSTEM. OVERNIGHT TEMPS ON MONDAY NIGHT SHOULD STAY A BIT A WARMER
THAN MOST GUIDANCE IS SUGGESTING DUE TO CLOUD COVER. TEMPERATURES
WILL BE SLIGHTLY ABOVE NORMAL.
WEDNESDAY AND THURSDAY. NORTHWESTERLY FLOW PATTERN WILL PERSIST WITH
DRY CONDITIONS AND SOME PASSING HIGH CLOUDS. A STRONGER SHORTWAVE
MAY DEVELOP TO THE NORTH AND WEST OF THE AREA BY THURSDAY...BUT
DISAGREEMENT AMONG MODELS WITH STRENGTH AND EVOLUTION OF THIS
SYSTEM.
AVIATION...SNOW WILL SPREAD ACROSS THE AREA THIS MORNING THROUGH THE
EARLY AFTERNOON HOURS WITH POSSIBLE MVFR AND IFR CONDITIONS AT ALL
TERMINALS. EXPECT MAINLY VFR CONDITIONS BY THIS AFTERNOON WITH
KELY SEEING MVFR AND IFR CONDITIONS THROUGH THE EARLY EVENING
HOURS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
91/86/90
AREA FORECAST DISCUSSION
NWS ELKO NV
848 AM PST FRI JAN 31 2014
.SYNOPSIS...SCATTERED TO NUMEROUS SNOW SHOWERS ARE ON TAP FOR
EASTERN NEVADA TODAY. DRY AND CONTINUED COLD CAN BE EXPECTED OVER
THE WEEKEND WITH ANOTHER WEAK SYSTEM POSSIBLE LATE SUNDAY NIGHT
INTO MONDAY. THIS WILL BRING ANOTHER SHOT OF LIGHT SNOW SHOWERS TO
THE FORECAST AREA.
&&
.UPDATE...RADAR SHOWING AN AREA OF LIGHT SNOW OVER NORTHERN LANDER
AND NORTHERN EUREKA COUNTIES AT THIS TIME ASSOCIATED WITH SHORT
WAVE MOVING THROUGH THE AREA. AS THIS SHORT WAVE MOVES TOWARDS THE
SOUTHEAST IT WILL BRING WIDESPREAD LIGHT SNOW TO EAST CENTRAL NV
LATE THIS MORNING AND AFTERNOON. HAVE UPDATED FORECASTS TO REFLECT
THIS. VALLEYS ACROSS WHITE PINE COUNTY AND SOUTHERN EUREKA COUNTY
COULD SEE UP TO AN INCH OF SNOW OUT OF THIS SYSTEM TODAY. ALSO
LOWER HIGH TEMPS TODAY. WITH 700 MB TEMPS OF -12C TO -14C MANY
AREAS WILL BE HARD PRESSED TO GET ABOVE THE MID 30S.
&&
.PREV DISCUSSION... /ISSUED AT 641 AM /
SYNOPSIS...ISOLATED TO SCATTERED LIGHT SNOW SHOWERS ARE ON TAP
FOR TODAY AS A WEAK UPPER SYSTEM PUSHES ACROSS NORTHERN NEVADA.
DRY AND CONTINUED COOL CAN BE EXPECTED OVER THE WEEKEND WITH
ANOTHER WEAK SYSTEM POSSIBLE LATE SUNDAY NIGHT INTO MONDAY. THIS
WILL BRING ANOTHER SHOT OF LIGHT SNOW SHOWERS TO THE FORECAST
AREA.
UPDATE...UPDATED CURRENT GRIDS TO REFLECT ONGOING WEATHER IN
NORTHERN LANDER/EUREKA COUNTIES. PERSISTANT AREA OF LIGHT SNOW
CONTINUES TO FALL IN THIS AREA...WHICH INCLUDES THE I-80 CORRIDOR.
THIS IS IN RESPONSE TO AN UPPER TROUGH APPROACHING FROM THE WEST.
EXPECT THE AREA TO CONTINUE THROUGH THE MORNING BASED ON LATEST
HRRR MODEL RUNS. ALL GRIDS HAVE BEEN UPDATED.
PREV DISCUSSION... /ISSUED AT 338 AM /
SHORT TERM...TODAY THROUGH SUNDAY. RADAR THIS MORNING IS
DEPICTING ISOLATED TO SCATTERED SNOW SHOWERS ACROSS PORTIONS OF
HUMBOLDT AND NORTHERN LANDER/EUREKA COUNTIES. THE REMOTE SITE IN
WINNEMUCCA IS NOW SHOWING A VISIBILITY OF 4 MILES...AND HAS BEEN
IMPROVING. COOP OBSERVER IN WINNEMUCCA REPORTED A QUICK 0.8 INCHES
WITH THE MIDNIGHT OBSERVATION. RUC13 IS SHOWING A BROAD SWATH OF
WEAK LIFT IN THE AREA OF LIGHT PRECIPITATION...AND OUT AHEAD OF
THE 500 MB TROUGH.
MODELS THIS MORNING ARE SHOWING A 500 MB TROUGH AXIS WEST OF
NEVADA. THIS FEATURE WILL BE CROSSING THE FORECAST AREA
TODAY. THE 3KM HRRR IS SHOWING LIGHT SNOW SHOWERS BREAKING OUT
FROM NORTHERN LANDER/EUREKA INTO ELKO COUNTY. HAVE INCREASED POPS
DURING THE MORNING AND VERY EARLY AFTERNOON HOURS IN THE NORTHERN
AND CENTRAL PARTS OF NEVADA. ANOTHER PIECE OF ENERGY WILL DIP
SOUTH AND WEST OF THE REGION...GOING THROUGH CALIFORNIA AND THEN
ARIZONA...WITH THE LAST REMNANTS OF THE UPPER LOW EXITING EARLY
SATURDAY. FOR TODAY EXPECT THE TROUGH WITH TH 500 MB COLD POOL TO
MOVE ACROSS THE AREA. SUFFICIENT INSTABILITY EXISTS TO ALLOW
SCATTERED SHOWERS TO FORM THIS AFTERNOON. THESE SHOWERS COULD DROP
A QUICK HALF INCH TO INCH DEPENDING ON WHERE THEY FORM...ALONG
WITH SUDDEN DROPS IN VISIBILITY.
THE FIRST TROUGH WILL PUSH THROUGH LATER THIS AFTERNOON AND
TONIGHT...WITH THE SECOND PIECE OF ENERGY...AS MENTIONED
EARLIER...PUSHING FURTHER SOUTH. SNOW SHOWERS WILL END WEST TO
EAST BY SATURDAY AFTERNOON...WITH A WEAK SHORTWAVE RIDGE TRYING TO
PUSH ACROSS SATURDAY NIGHT INTO SUNDAY. GFS IS A LITTLE STRONG
WITH ENERGY PUSHING IN FROM THE NORTHWEST. AT THIS TIME...THIS
APPEARS DRY AND SO WILL CONTINUE WITH QUIET CONDITIONS DURING THE
SUNDAY AFTERNOON PERIOD.
LONG TERM...SUNDAY NIGHT THROUGH NEXT THURSDAY. MODELS IS GOOD
AGREEMENT THROUGH TUESDAY WITH NORTHWESTERLY FLOW PATTERN AND
SHORTWAVE PUSHING THROUGH AREA MONDAY...BUT SLIGHTLY OUT OF PHASE BY
WEDNESDAY AND THURSDAY WITH DEVELOPING TROUGH TO NORTHWEST BY END OF
PERIOD.
SUNDAY NIGHT THROUGH TUESDAY. A CLIPPER TYPE SHORTWAVE WILL MOVE
ACROSS THE REGION MONDAY THROUGH TUESDAY MORNING BRINGING A DECENT
SHOT OF SNOW...THUS INCREASED CLOUDS AND POPS FOR THIS TIME FRAME.
EC SLIGHTLY DEEPER AND COLDER WITH THIS SYSTEM BUT OVERALL MODELS ARE
COMING INTO BETTER AGREEMENT AND CONFIDENCE IS INCREASING WITH THIS
SYSTEM. OVERNIGHT TEMPS ON MONDAY NIGHT SHOULD STAY A BIT A WARMER
THAN MOST GUIDANCE IS SUGGESTING DUE TO CLOUD COVER. TEMPERATURES
WILL BE SLIGHTLY ABOVE NORMAL.
WEDNESDAY AND THURSDAY. NORTHWESTERLY FLOW PATTERN WILL PERSIST WITH
DRY CONDITIONS AND SOME PASSING HIGH CLOUDS. A STRONGER SHORTWAVE
MAY DEVELOP TO THE NORTH AND WEST OF THE AREA BY THURSDAY...BUT
DISAGREEMENT AMONG MODELS WITH STRENGTH AND EVOLUTION OF THIS
SYSTEM.
AVIATION...SNOW WILL SPREAD ACROSS THE AREA THIS MORNING THROUGH THE
EARLY AFTERNOON HOURS WITH POSSIBLE MVFR AND IFR CONDITIONS AT ALL
TERMINALS. EXPECT MAINLY VFR CONDITIONS BY THIS AFTERNOON WITH
KELY SEEING MVFR AND IFR CONDITIONS THROUGH THE EARLY EVENING
HOURS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM PST THIS AFTERNOON FOR
NORTHERN LANDER COUNTY AND NORTHERN EUREKA COUNTY.
&&
$$
91/86/90
AREA FORECAST DISCUSSION
NWS ELKO NV
641 AM PST FRI JAN 31 2014
.SYNOPSIS...ISOLATED TO SCATTERED LIGHT SNOW SHOWERS ARE ON TAP
FOR TODAY AS A WEAK UPPER SYSTEM PUSHES ACROSS NORTHERN NEVADA.
DRY AND CONTINUED COOL CAN BE EXPECTED OVER THE WEEKEND WITH
ANOTHER WEAK SYSTEM POSSIBLE LATE SUNDAY NIGHT INTO MONDAY. THIS
WILL BRING ANOTHER SHOT OF LIGHT SNOW SHOWERS TO THE FORECAST
AREA.
&&
.UPDATE...UPDATED CURRENT GRIDS TO REFLECT ONGOING WEATHER IN
NORTHERN LANDER/EUREKA COUNTIES. PERSISTANT AREA OF LIGHT SNOW
CONTINUES TO FALL IN THIS AREA...WHICH INCLUDES THE I-80 CORRIDOR.
THIS IS IN RESPONSE TO AN UPPER TROUGH APPROACHING FROM THE WEST.
EXPECT THE AREA TO CONTINUE THROUGH THE MORNING BASED ON LATEST
HRRR MODEL RUNS. ALL GRIDS HAVE BEEN UPDATED.
&&
.PREV DISCUSSION... /ISSUED AT 338 AM /
SHORT TERM...TODAY THROUGH SUNDAY. RADAR THIS MORNING IS
DEPICTING ISOLATED TO SCATTERED SNOW SHOWERS ACROSS PORTIONS OF
HUMBOLDT AND NORTHERN LANDER/EUREKA COUNTIES. THE REMOTE SITE IN
WINNEMUCCA IS NOW SHOWING A VISIBILITY OF 4 MILES...AND HAS BEEN
IMPROVING. COOP OBSERVER IN WINNEMUCCA REPORTED A QUICK 0.8 INCHES
WITH THE MIDNIGHT OBSERVATION. RUC13 IS SHOWING A BROAD SWATH OF
WEAK LIFT IN THE AREA OF LIGHT PRECIPITATION...AND OUT AHEAD OF
THE 500 MB TROUGH.
MODELS THIS MORNING ARE SHOWING A 500 MB TROUGH AXIS WEST OF
NEVADA. THIS FEATURE WILL BE CROSSING THE FORECAST AREA
TODAY. THE 3KM HRRR IS SHOWING LIGHT SNOW SHOWERS BREAKING OUT
FROM NORTHERN LANDER/EUREKA INTO ELKO COUNTY. HAVE INCREASED POPS
DURING THE MORNING AND VERY EARLY AFTERNOON HOURS IN THE NORTHERN
AND CENTRAL PARTS OF NEVADA. ANOTHER PIECE OF ENERGY WILL DIP
SOUTH AND WEST OF THE REGION...GOING THROUGH CALIFORNIA AND THEN
ARIZONA...WITH THE LAST REMNANTS OF THE UPPER LOW EXITING EARLY
SATURDAY. FOR TODAY EXPECT THE TROUGH WITH TH 500 MB COLD POOL TO
MOVE ACROSS THE AREA. SUFFICIENT INSTABILITY EXISTS TO ALLOW
SCATTERED SHOWERS TO FORM THIS AFTERNOON. THESE SHOWERS COULD DROP
A QUICK HALF INCH TO INCH DEPENDING ON WHERE THEY FORM...ALONG
WITH SUDDEN DROPS IN VISIBILITY.
THE FIRST TROUGH WILL PUSH THROUGH LATER THIS AFTERNOON AND
TONIGHT...WITH THE SECOND PIECE OF ENERGY...AS MENTIONED
EARLIER...PUSHING FURTHER SOUTH. SNOW SHOWERS WILL END WEST TO
EAST BY SATURDAY AFTERNOON...WITH A WEAK SHORTWAVE RIDGE TRYING TO
PUSH ACROSS SATURDAY NIGHT INTO SUNDAY. GFS IS A LITTLE STRONG
WITH ENERGY PUSHING IN FROM THE NORTHWEST. AT THIS TIME...THIS
APPEARS DRY AND SO WILL CONTINUE WITH QUIET CONDITIONS DURING THE
SUNDAY AFTERNOON PERIOD.
LONG TERM...SUNDAY NIGHT THROUGH NEXT THURSDAY. MODELS IS GOOD
AGREEMENT THROUGH TUESDAY WITH NORTHWESTERLY FLOW PATTERN AND
SHORTWAVE PUSHING THROUGH AREA MONDAY...BUT SLIGHTLY OUT OF PHASE BY
WEDNESDAY AND THURSDAY WITH DEVELOPING TROUGH TO NORTHWEST BY END OF
PERIOD.
SUNDAY NIGHT THROUGH TUESDAY. A CLIPPER TYPE SHORTWAVE WILL MOVE
ACROSS THE REGION MONDAY THROUGH TUESDAY MORNING BRINGING A DECENT
SHOT OF SNOW...THUS INCREASED CLOUDS AND POPS FOR THIS TIME FRAME.
EC SLIGHTLY DEEPER AND COLDER WITH THIS SYSTEM BUT OVERALL MODELS ARE
COMING INTO BETTER AGREEMENT AND CONFIDENCE IS INCREASING WITH THIS
SYSTEM. OVERNIGHT TEMPS ON MONDAY NIGHT SHOULD STAY A BIT A WARMER
THAN MOST GUIDANCE IS SUGGESTING DUE TO CLOUD COVER. TEMPERATURES
WILL BE SLIGHTLY ABOVE NORMAL.
WEDNESDAY AND THURSDAY. NORTHWESTERLY FLOW PATTERN WILL PERSIST WITH
DRY CONDITIONS AND SOME PASSING HIGH CLOUDS. A STRONGER SHORTWAVE
MAY DEVELOP TO THE NORTH AND WEST OF THE AREA BY THURSDAY...BUT
DISAGREEMENT AMONG MODELS WITH STRENGTH AND EVOLUTION OF THIS
SYSTEM.
AVIATION...SNOW WILL SPREAD ACROSS THE AREA THIS MORNING THROUGH THE
EARLY AFTERNOON HOURS WITH POSSIBLE MVFR AND IFR CONDITIONS AT ALL
TERMINALS. EXPECT MAINLY VFR CONDITIONS BY THIS AFTERNOON WITH
KELY SEEING MVFR AND IFR CONDITIONS THROUGH THE EARLY EVENING
HOURS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM PST THIS AFTERNOON FOR
NORTHERN LANDER COUNTY AND NORTHERN EUREKA COUNTY.
&&
$$
86/90
AREA FORECAST DISCUSSION...CORRECTED
NWS ELKO NV
338 AM PST FRI JAN 31 2014
.SYNOPSIS...ISOLATED TO SCATTERED LIGHT SNOW SHOWERS ARE ON TAP
FOR TODAY AS A WEAK UPPER SYSTEM PUSHES ACROSS NORTHERN NEVADA. DRY AND
CONTINUED COOL CAN BE EXPECTED OVER THE WEEKEND WITH ANOTHER WEAK
SYSTEM POSSIBLE LATE SUNDAY NIGHT INTO MONDAY. THIS WILL BRING
ANOTHER SHOT OF LIGHT SNOW SHOWERS TO THE FORECAST AREA.
&&
.SHORT TERM...TODAY THROUGH SUNDAY. RADAR THIS MORNING IS
DEPICTING ISOLATED TO SCATTERED SNOW SHOWERS ACROSS PORTIONS OF
HUMBOLDT AND NORTHERN LANDER/EUREKA COUNTIES. THE REMOTE SITE IN
WINNEMUCCA IS NOW SHOWING A VISIBILITY OF 4 MILES...AND HAS BEEN
IMPROVING. COOP OBSERVER IN WINNEMUCCA REPORTED A QUICK 0.8
INCHES WITH THE MIDNIGHT OBSERVATION. RUC13 IS SHOWING A BROAD
SWATH OF WEAK LIFT IN THE AREA OF LIGHT PRECIPITATION...AND OUT
AHEAD OF THE 500 MB TROUGH.
MODELS THIS MORNING ARE SHOWING A 500 MB TROUGH AXIS WEST OF
NEVADA. THIS FEATURE WILL BE CROSSING THE FORECAST AREA
TODAY. THE 3KM HRRR IS SHOWING LIGHT SNOW SHOWERS BREAKING OUT
FROM NORTHERN LANDER/EUREKA INTO ELKO COUNTY. HAVE INCREASED POPS
DURING THE MORNING AND VERY EARLY AFTERNOON HOURS IN THE NORTHERN
AND CENTRAL PARTS OF NEVADA. ANOTHER PIECE OF ENERGY WILL DIP
SOUTH AND WEST OF THE REGION...GOING THROUGH CALIFORNIA AND THEN
ARIZONA...WITH THE LAST REMNANTS OF THE UPPER LOW EXITING EARLY
SATURDAY. FOR TODAY EXPECT THE TROUGH WITH TH 500 MB COLD POOL TO
MOVE ACROSS THE AREA. SUFFICIENT INSTABILITY EXISTS TO ALLOW
SCATTERED SHOWERS TO FORM THIS AFTERNOON. THESE SHOWERS COULD DROP
A QUICK HALF INCH TO INCH DEPENDING ON WHERE THEY FORM...ALONG
WITH SUDDEN DROPS IN VISIBILITY.
THE FIRST TROUGH WILL PUSH THROUGH LATER THIS AFTERNOON AND
TONIGHT...WITH THE SECOND PIECE OF ENERGY...AS MENTIONED
EARLIER...PUSHING FURTHER SOUTH. SNOW SHOWERS WILL END WEST TO
EAST BY SATURDAY AFTERNOON...WITH A WEAK SHORTWAVE RIDGE TRYING TO
PUSH ACROSS SATURDAY NIGHT INTO SUNDAY. GFS IS A LITTLE STRONG
WITH ENERGY PUSHING IN FROM THE NORTHWEST. AT THIS TIME...THIS
APPEARS DRY AND SO WILL CONTINUE WITH QUIET CONDITIONS DURING THE
SUNDAY AFTERNOON PERIOD.
.LONG TERM...SUNDAY NIGHT THROUGH NEXT THURSDAY. MODELS IS GOOD
AGREEMENT THROUGH TUESDAY WITH NORTHWESTERLY FLOW PATTERN AND
SHORTWAVE PUSHING THROUGH AREA MONDAY...BUT SLIGHTLY OUT OF PHASE BY
WEDNESDAY AND THURSDAY WITH DEVELOPING TROUGH TO NORTHWEST BY END OF
PERIOD.
SUNDAY NIGHT THROUGH TUESDAY. A CLIPPER TYPE SHORTWAVE WILL MOVE
ACROSS THE REGION MONDAY THROUGH TUESDAY MORNING BRINGING A DECENT
SHOT OF SNOW...THUS INCREASED CLOUDS AND POPS FOR THIS TIME FRAME.
EC SLIGHTLY DEEPER AND COLDER WITH THIS SYSTEM BUT OVERALL MODELS ARE
COMING INTO BETTER AGREEMENT AND CONFIDENCE IS INCREASING WITH THIS
SYSTEM. OVERNIGHT TEMPS ON MONDAY NIGHT SHOULD STAY A BIT A WARMER
THAN MOST GUIDANCE IS SUGGESTING DUE TO CLOUD COVER. TEMPERATURES
WILL BE SLIGHTLY ABOVE NORMAL.
WEDNESDAY AND THURSDAY. NORTHWESTERLY FLOW PATTERN WILL PERSIST WITH
DRY CONDITIONS AND SOME PASSING HIGH CLOUDS. A STRONGER SHORTWAVE
MAY DEVELOP TO THE NORTH AND WEST OF THE AREA BY THURSDAY...BUT
DISAGREEMENT AMONG MODELS WITH STRENGTH AND EVOLUTION OF THIS
SYSTEM.
&&
.AVIATION...SNOW WILL SPREAD ACROSS THE AREA THIS MORNING THROUGH THE
EARLY AFTERNOON HOURS WITH POSSIBLE MVFR AND IFR CONDITIONS AT ALL
TERMINALS. EXPECT MAINLY VFR CONDITIONS BY THIS AFTERNOON WITH
KELY SEEING MVFR AND IFR CONDITIONS THROUGH THE EARLY EVENING
HOURS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
86/90
AREA FORECAST DISCUSSION
NWS ELKO NV
318 AM PST FRI JAN 31 2014
.SYNOPSIS...ISOLATED TO SCATTERED LIGHT SNOW SHOWERS ARE ON TAP
FOR TODAY AS A WEAK UPPER SYSTEM PUSHES ACROSS NORTHERN NEVADA. DRY AND
CONTINUED COOL CAN BE EXPECTED OVER THE WEEKEND WITH ANOTHER WEAK
SYSTEM POSSIBLE LATE SUNDAY NIGHT INTO MONDAY. THIS WILL BRING
ANOTHER SHOT OF LIGHT SNOW SHOWERS TO THE FORECAST AREA.
&&
.SHORT TERM...TODAY THROUGH SUNDAY. RADAR THIS MORNING IS
DEPICTING ISOLATED TO SCATTERED SNOW SHOWERS ACROSS PORTIONS OF
HUMBOLDT AND NORTHERN LANDER/EUREKA COUNTIES. THE REMOTE SITE IN
WINNEMUCCA IS NOW SHOWING A VISIBILITY OF 4 MILES...AND HAS BEEN
IMPROVING. COOP OBSERVER IN WINNEMUCCA REPORTED A QUICK 0.8
INCHES WITH THE MIDNIGHT OBSERVATION. RUC13 IS SHOWING A BROAD
SWATH OF WEAK LIFT IN THE AREA OF LIGHT PRECIPITATION...AND OUT
AHEAD OF THE 500 MB TROUGH.
MODELS THIS MORNING ARE SHOWING A 500 MB TROUGH AXIS WEST OF
NEVADA. THIS FEATURE WILL BE CROSSING THE FORECAST AREA
TODAY. THE 3KM HRRR IS SHOWING LIGHT SNOW SHOWERS BREAKING OUT
FROM NORTHERN LANDER/EUREKA INTO ELKO COUNTY. HAVE INCREASED POPS
DURING THE MORNING AND VERY EARLY AFTERNOON HOURS IN THE NORTHERN
AND CENTRAL PARTS OF NEVADA. ANOTHER PIECE OF ENERGY WILL DIP
SOUTH AND WEST OF THE REGION...GOING THROUGH CALIFORNIA AND THEN
ARIZONA...WITH THE LAST REMNANTS OF THE UPPER LOW EXITING EARLY
SATURDAY. FOR TODAY EXPECT THE TROUGH WITH TH 500 MB COLD POOL TO
MOVE ACROSS THE AREA. SUFFICIENT INSTABILITY EXISTS TO ALLOW
SCATTERED SHOWERS TO FORM THIS AFTERNOON. THESE SHOWERS COULD DROP
A QUICK HALF INCH TO INCH DEPENDING ON WHERE THEY FORM...ALONG
WITH SUDDEN DROPS IN VISIBILITY.
THE FIRST TROUGH WILL PUSH THROUGH LATER THIS AFTERNOON AND
TONIGHT...WITH THE SECOND PIECE OF ENERGY...AS MENTIONED
EARLIER...PUSHING FURTHER SOUTH. SNOW SHOWERS WILL END WEST TO
EAST BY SATURDAY AFTERNOON...WITH A WEAK SHORTWAVE RIDGE TRYING TO
PUSH ACROSS SATURDAY NIGHT INTO SUNDAY. GFS IS A LITTLE STRONG
WITH ENERGY PUSHING IN FROM THE NORTHWEST. AT THIS TIME...THIS
APPEARS DRY AND SO WILL CONTINUE WITH QUIET CONDITIONS DURING THE
SUNDAY AFTERNOON PERIOD.
.LONG TERM...SUNDAY NIGHT THROUGH NEXT THURSDAY. MODELS IS GOOD
AGREEMENT THROUGH TUESDAY WITH NORTHWESTERLY FLOW PATTERN AND
SHORTWAVE PUSHING THROUGH AREA MONDAY...BUT SLIGHTLY OUT OF PHASE BY
WEDNESDAY AND THURSDAY WITH DEVELOPING TROUGH TO NORTHWEST BY END OF
PERIOD.
SUNDAY NIGHT THROUGH TUESDAY. A CLIPPER TYPE SHORTWAVE WILL MOVE
ACROSS THE REGION MONDAY THROUGH TUESDAY MORNING BRINGING A DECENT
SHOT OF SNOW...THUS INCREASED CLOUDS AND POPS FOR THIS TIME FRAME.
EC SLIGHTLY DEEPER AND COLDER WITH THIS SYSTEM BUT OVERALL MODELS ARE
COMING INTO BETTER AGREEMENT AND CONFIDENCE IS INCREASING WITH THIS
SYSTEM. OVERNIGHT TEMPS ON MONDAY NIGHT SHOULD STAY A BIT A WARMER
THAN MOST GUIDANCE IS SUGGESTING DUE TO CLOUD COVER. TEMPERATURES
WILL BE SLIGHTLY ABOVE NORMAL.
WEDNESDAY AND THURSDAY. NORTHWESTERLY FLOW PATTERN WILL PERSIST WITH
DRY CONDITIONS AND SOME PASSING HIGH CLOUDS. A STRONGER SHORTWAVE
MAY DEVELOP TO THE NORTH AND WEST OF THE AREA BY THURSDAY...BUT
DISAGREEMENT AMONG MODELS WITH STRENGTH AND EVOLUTION OF THIS
SYSTEM.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...SNOW WILL SPREAD ACROSS THE
AREA THIS MORNING THROUGH THE EARLY AFTERNOON HOURS WITH POSSIBLE
MVFR AND IFR CONDITIONS AT ALL TERMINALS. EXPECT MAINLY VFR
CONDITIONS BY THIS AFTERNOON WITH KELY SEEING MVFR AND IFR
CONDITIONS THROUGH THE EARLY EVENING HOURS. NONE. &&
$$
86/90
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
710 PM EST SAT FEB 1 2014
.SYNOPSIS...
LOW PRESSURE WILL PASS THROUGH THE SAINT LAWRENCE VALLEY OVERNIGHT INTO
SUNDAY MORNING BRINGING WIDESPREAD LIGHT SNOW AND MIXED
PRECIPITATION TO THE AREA ALONG WITH MILD MID-WINTER TEMPERATURES.
A RETURN OF SEASONABLY COOL AND DRY WEATHER IS THEN EXPECTED BY
MONDAY INTO TUESDAY BEFORE ADDITIONAL WINTRY PRECIPITATION LIKELY
RETURNS BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 659 PM EST SATURDAY...PREVIOUS FORECAST STILL LOOKS GOOD AT
THIS TIME...SO HAVE JUST UPDATED THE GRIDS WITH THE LATEST SURFACE
OBSERVATIONS. HAVE KEPT IN A CHANCE FOR A MIX OF RAIN AND SNOW
ACROSS THE CHAMPLAIN VALLEY OVERNIGHT...WITH A CHANCE FOR SOME
MIXED PRECIPITATION POSSIBLE ACROSS CENTRAL AND SOUTHERN VERMONT
OVERNIGHT.
PREVIOUS DISCUSSION FROM 307 PM EST SATURDAY...LATEST 12Z MODEL SUITE
INCLUDING 18Z RAP PROGS STILL IN GOOD AGREEMENT SHOWING A
WIDESPREAD LIGHT TO MODERATE WINTER PCPN EVENT AFFECTING OUR AREA
TONIGHT INTO SUNDAY MORNING AS LOW PRESSURE TRACKS THROUGH THE
SLV. FAIRLY ROBUST WARM THERMAL ADVECTION ON THE NOSE OF 50-60KT
SOUTHWESTERLY 850 JET ALONG WITH INCREASINGLY MOIST LOWER TO MID
LEVELS SHOULD BE MORE THAN SUFFICIENT TO PRODUCE WIDESPREAD PCPN
ON THE ORDER OF A QUARTER TO A HALF AN INCH ACROSS THE SLV/NRN
DACKS AND NRN GREENS. LESSER AMTS ELSEWHERE (0.25 OR
LESS)CHAMPLAIN/CT RVR VALLEYS AND MUCH OF SOUTH CENTRAL VT WHICH
WILL BE AFFECTED TO A CONSIDERABLE DEGREE BY DOWNSLOPING EFFECTS.
PCPN MAY ALSO MIX WITH PERIODS OF SLEET OR EVEN RAIN AT
TIMES...NAMELY AT PCPN ONSET THROUGH EARLY THIS EVENING WHEN NEAR-
SFC TEMPS ARE THE MILDEST...AND AGAIN OVERNIGHT WHEN MID-LEVEL
WARM NOSE REACHES MOST NORTHWARD EXENT. NONETHELESS...FEEL WITH
SUCH DRY TD VALUES WET BULB PROCESSES WILL TEND TO DOMINATE OVER
TIME AND MOST OF THE PCPN...ESP IN THE ADVSY AREA WILL FALL IN THE
FORM OF SNOW. LOOKING AT AMOUNTS GENERALLY IN THE 2-5/3-6 INCH
RANGE IN THESE AREAS BY MORNING WITH ISOLATED AMOUNTS TO PERHAPS
7/8 INCHES IN FAVORED HIGHER ELEV SPOTS. ELSEWHERE...A GENERAL
DUSTING TO 2 INCHES LOOKS REASONABLE WITH LOWEST AMOUNTS FAR
SOUTHERN VT WHICH WILL BE FURTHER REMOVED FROM BEST
WAA/DYNAMICS/MOISTURE. ADDITIONALLY AFOREMENTIONED SHADOWING
EFFECTS WILL LIKELY PRODUCE A LOCAL MINIMUM IN THE IMMEDIATE
KPBG/KBTV VCNTY...ESP AFTER INITIAL WARM ADVECTION PCPN BURST THIS
EVENING WHEN CORE OF SOUTHWESTERLY 850 JET MOVES INTO THE AREA.
LOWS TONIGHT MAINLY FROM THE UPPER 20S TO LOWER 30S UNDER
CONTINUED SOUTH/SOUTHWESTERLY FLOW.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 307 PM EST SATURDAY...BY TOMORROW MORNING...SFC LOW WILL BE
QUICKLY EXITING OFF TO OUR NORTHEAST INTO EASTERN CANADA WITH ANY
LINGERING LIGHT SNOWS AND/OR MIXED PCPN GENERALLY ENDING BY NOON.
ANY BACK END ACCUMULATIONS SHOULD BE LIGHT. THE SYSTEM`S SFC COLD
FRONT WILL BE IN THE PROCESS OF SWINGING THROUGH THE AREA...AND
BEHIND THIS BOUNDARY WINDS WILL TREND WEST TO NORTHWESTERLY BY
DAYS END. WITH SFC FRONTAL PASSAGE IN THE LATE MORNING THROUGH
MID-AFTERNOON HOURS...A NEAR NORMAL DIURNAL TEMPERATURE TREND IS
EXPECTED AS DAYTIME MAXES TOP OUT IN THE 35 TO 40 DEGREE RANGE FOR
MOST SPOTS.
THEREAFTER SENSIBLE WEATHER TRENDS QUIET AND SEASONABLE AS BROAD SFC
HIGH PRESSURE BUILDS INTO THE REGION BRIDGED ALOFT BY WESTERLY
ZONAL FLOW. THUS PRIOR IDEA OF CLEAR TO PTLY CLOUDY SKIES ALONG
WITH DRY AND COOLER WEATHER STILL LOOKS RIGHT ON TRACK. LOWS SUNDAY
NIGHT GENERALLY 10 TO 20 ABOVE...WITH HIGHS ON MONDAY 23 TO 30. DID
OPT TO TREND ON THE COLDER SIDE OF NUMERICAL GUIDANCE ON MIN TEMPS
MONDAY NIGHT WHEN CENTER OF 1030+ MB SFC HIGH BUILDS DIRECTLY ATOP
THE FORECAST AREA ALONG WITH IDEAL RADIATIVE EFFECTS. THIS WOULD
SUGGEST READINGS BOTTOMING OUT FROM 5 BELOW TO 5 ABOVE WITH
LOCALIZED COLDER SPOTS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 305 PM EST SATURDAY...THE LONG TERM FCST FOCUS IS WEDS INTO
THURS TIME PERIOD ASSOCIATED WITH POTENTIAL WINTER STORM. THE
LATEST 12Z NWP GUIDANCE AND BOTH 00Z AND 12Z ENSEMBLE DATA IN VERY
GOOD AGREEMENT...RESULTING IN ABOVE NORMAL CONFIDENCE FOR UPCOMING
SYSTEM. THE LATEST TRENDS DO SUPPORT A SLIGHTLY MORE SOUTHERN
TRACK...WHICH PLACES OUR CWA WELL ESTABLISHED IN THE COLD SECTOR
ALONG WITH LESS QPF/SNOWFALL.
LARGE SCALE SYNOPTIC SETUP SHOWS DIGGING MID/UPPER LVL TROF ACRS
THE INTER MOUNTAIN WEST WITH POTENT 5H VORT EJECTING INTO THE
CENTRAL PLAINS BY 12Z TUES. THIS WL HELP IN THE DEVELOPMENT OF SFC
LOW PRES ACRS THE MS VALLEY...WHILE A FAST CONFLUENT FLW ALOFT
CONTS ACRS THE EASTERN CONUS. SFC LOW PRES WL TRACK TWD THE OHIO
VALLEY BY 06Z WEDS...THEN NEAR PITTSBURGH PA BY 12Z WEDS AND NYC
BY WEDS EVENING. THIS SYSTEM WL HAVE PLENTY OF DEEP SUB-TROPICAL
MOISTURE TO WORK WITH AND A FAVORABLE DUAL JET STRUCTURE. LATEST
GUIDANCE SUPPORTS ABOVE NORMAL PWS BTWN 0.75" AND 1.25" ACRS THE
MID ATLANTIC STATES...WITH A SHARP NORTH TO SOUTH GRADIENT ACRS
OUR CWA. IN ADDITION...FAST MOVEMENT OF SYSTEM AND NO CLOSED 5H/7H
CIRCULATIONS WL PREVENT STORM FROM BEING A BLOCKBUSTER AND MORE OF
A MODERATE PREICP/SNOWFALL EVENT FOR WEDS INTO THURS. THE SHARP
THERMAL PACKING ACRS OUR CWA...INDICATES STRONG LOW TO MID LVL FGEN/WAA
FORCING ASSOCIATED WITH NOSE OF 40 TO 50 KNOT 85H JET AND RRQ OF
25H JET ACRS SOUTHERN CANADA. RESULTING IN A PERIOD OF DEEP LAYER
LIFT/MOISTURE...WITH GREATEST IMPACTS ACRS OUR CENTRAL/SOUTHERN CWA. VERY
EARLY INDICATIONS SUPPORT QPF RANGING FROM 0.25 INTERNATIONAL
BORDER TO 0.75" RUTLAND/WINDSOR COUNTIES...RESULTING IN ADVISORY
TYPE EVENT NEAR THE BORDER AND WARNINGS ACRS CENTRAL/SOUTHERN VT
ZNS. ANY SHIFT FURTHER NORTH OR SOUTH WOULD GREATLY IMPACT THE
AMOUNT OF QPF/SNOWFALL EXPECTED AND LLVL THERMAL PROFILES. WL CONT
TO MENTION CAT POPS FOR WEDS WITH THERMAL SOUNDINGS SUPPORTING ALL
SNOW FOR OUR ENTIRE CWA. SNOW WL TAPER OFF WEDS NIGHT INTO
THURSDAY WITH A BRIEF PERIOD OF UPSLOPE SNOW SHOWERS
POSSIBLE...BUT DRIER AIR ASSOCIATED WITH SFC HIGH PRES BUILDS INTO
OUR REGION. EXPECT NEAR NORMAL TEMPS FOR THE PERIOD WITH DAILY
HIGHS IN THE 20S AND LOWS IN THE SINGLE DIGITS/TEENS...EXCEPT BLW
NORMAL READINGS ON THURS/FRIDAY ASSOCIATED WITH LLVL CAA BEHIND
DEPARTING SFC LOW PRES. ANOTHER SYSTEM MAY IMPACT OUR REGION NEXT
WEEKEND AS ACTIVE STORM PATTERN DEVELOPS WITH POTENTIAL SYSTEMS
EVERY COUPLE OF DAYS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...PBG/BTV MVFR/IFR CONDITIONS FOR VIS TIL 06Z.
IFR CONDITIONS AT MPV BY 23Z AND MAINLY MVFR CONDITIONS
PREVAILING AT RUT AS BEST MOISTURE/LIFT IS NORTH OF THIS TAF SITE.
THE HEAVIER AND STEADIER PRECIP WL EXIT OUR TAF SITES BY 06Z FOR
MVFR/VFR WITH EXCEPTION OF SLK/MSS...WHICH WL CONT TO SEE PERIODS
OF -SN WITH IFR CONDITIONS PREVAILING. THINKING BL TEMPS WARM
ENOUGH AT PBG/BTV FOR A MIXTURE OF -RASN BY 06Z WITH VIS BTWN
3-5SM...ESPECIALLY AS BETTER LIFTS SHIFTS NORTH OF REGION. A
DEVELOPING SW JET OF 45 TO 55 KNOTS BTWN 2500 AND 3500 FT AGL WL
PRODUCE AREAS OF TURBULENCE...ESPECIALLY IN THE MTNS...WITH SOME
SFC WIND GUSTS TO 20 KNOTS POSSIBLE. SOME LLVL WS WL BE POSSIBLE
AT MSS WITH NE SFC FLW OF 10 KNTS...WHILE FLW ALOFT IS FROM THE
SW.
COLD FRNT SWEEPS ACRS OUR CWA BTWN 14Z-18Z SUNDAY WITH ANOTHER
BRIEF PERIOD OF PRECIP POSSIBLE WITH MVFR/IFR CONDITIONS AND A
WIND SHIFT TO THE W/NW.
OUTLOOK 00Z MONDAY THROUGH WEDNESDAY...SFC HIGH PRES WITH VFR
CONDITIONS WL PREVAIL FROM 00Z MONDAY THRU 06Z WEDS. NEXT SYSTEM
WITH WIDESPREAD SNOW AND IFR CONDITIONS WL IMPACT OUR TAF SITES BY
12Z WEDS.
&&
.EQUIPMENT...
AS OF 710 PM EST SATURDAY...THE AUTOMATED SURFACE OBSERVING SYSTEM (ASOS)
AT THE KNAPP STATE AIRPORT IN BARRE-MONTPELIER VERMONT (KMPV) HAS
NOT TRANSMITTED AN OBSERVATION FROM THIS SITE SINCE 1551Z ON
FEBRUARY 1ST. THE FEDERAL AVIATION ADMINISTRATION (FAA) HAS
INFORMED THE NATIONAL WEATHER SERVICE THAT THIS IS DUE A TELEPHONE
COMMUNICATIONS LINE ISSUE. THERE IS NO ESTIMATE AVAILABLE AT THIS
TIME AS TO WHEN SERVICE WILL BE RESTORED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST SUNDAY FOR VTZ002>004-
006-007-016.
NY...WINTER WEATHER ADVISORY UNTIL 11 AM EST SUNDAY FOR NYZ026>031-
034-087.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/WGH
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER/SLW
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
659 PM EST SAT FEB 1 2014
.SYNOPSIS...
LOW PRESSURE WILL PASS THROUGH THE SAINT LAWRENCE VALLEY OVERNIGHT INTO
SUNDAY MORNING BRINGING WIDESPREAD LIGHT SNOW AND MIXED
PRECIPITATION TO THE AREA ALONG WITH MILD MID-WINTER TEMPERATURES.
A RETURN OF SEASONABLY COOL AND DRY WEATHER IS THEN EXPECTED BY
MONDAY INTO TUESDAY BEFORE ADDITIONAL WINTRY PRECIPITATION LIKELY
RETURNS BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 659 PM EST SATURDAY...PREVIOUS FORECAST STILL LOOKS GOOD AT
THIS TIME...SO HAVE JUST UPDATED THE GRIDS WITH THE LATEST SURFACE
OBSERVATIONS. HAVE KEPT IN A CHANCE FOR A MIX OF RAIN AND SNOW
ACROSS THE CHAMPLAIN VALLEY OVERNIGHT...WITH A CHANCE FOR SOME
MIXED PRECIPITATION POSSIBLE ACROSS CENTRAL AND SOUTHERN VERMONT
OVERNIGHT.
PREVIOUS DISCUSSION FROM 307 PM EST SATURDAY...LATEST 12Z MODEL SUITE
INCLUDING 18Z RAP PROGS STILL IN GOOD AGREEMENT SHOWING A
WIDESPREAD LIGHT TO MODERATE WINTER PCPN EVENT AFFECTING OUR AREA
TONIGHT INTO SUNDAY MORNING AS LOW PRESSURE TRACKS THROUGH THE
SLV. FAIRLY ROBUST WARM THERMAL ADVECTION ON THE NOSE OF 50-60KT
SOUTHWESTERLY 850 JET ALONG WITH INCREASINGLY MOIST LOWER TO MID
LEVELS SHOULD BE MORE THAN SUFFICIENT TO PRODUCE WIDESPREAD PCPN
ON THE ORDER OF A QUARTER TO A HALF AN INCH ACROSS THE SLV/NRN
DACKS AND NRN GREENS. LESSER AMTS ELSEWHERE (0.25 OR
LESS)CHAMPLAIN/CT RVR VALLEYS AND MUCH OF SOUTH CENTRAL VT WHICH
WILL BE AFFECTED TO A CONSIDERABLE DEGREE BY DOWNSLOPING EFFECTS.
PCPN MAY ALSO MIX WITH PERIODS OF SLEET OR EVEN RAIN AT
TIMES...NAMELY AT PCPN ONSET THROUGH EARLY THIS EVENING WHEN NEAR-
SFC TEMPS ARE THE MILDEST...AND AGAIN OVERNIGHT WHEN MID-LEVEL
WARM NOSE REACHES MOST NORTHWARD EXENT. NONETHELESS...FEEL WITH
SUCH DRY TD VALUES WET BULB PROCESSES WILL TEND TO DOMINATE OVER
TIME AND MOST OF THE PCPN...ESP IN THE ADVSY AREA WILL FALL IN THE
FORM OF SNOW. LOOKING AT AMOUNTS GENERALLY IN THE 2-5/3-6 INCH
RANGE IN THESE AREAS BY MORNING WITH ISOLATED AMOUNTS TO PERHAPS
7/8 INCHES IN FAVORED HIGHER ELEV SPOTS. ELSEWHERE...A GENERAL
DUSTING TO 2 INCHES LOOKS REASONABLE WITH LOWEST AMOUNTS FAR
SOUTHERN VT WHICH WILL BE FURTHER REMOVED FROM BEST
WAA/DYNAMICS/MOISTURE. ADDITIONALLY AFOREMENTIONED SHADOWING
EFFECTS WILL LIKELY PRODUCE A LOCAL MINIMUM IN THE IMMEDIATE
KPBG/KBTV VCNTY...ESP AFTER INITIAL WARM ADVECTION PCPN BURST THIS
EVENING WHEN CORE OF SOUTHWESTERLY 850 JET MOVES INTO THE AREA.
LOWS TONIGHT MAINLY FROM THE UPPER 20S TO LOWER 30S UNDER
CONTINUED SOUTH/SOUTHWESTERLY FLOW.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 307 PM EST SATURDAY...BY TOMORROW MORNING...SFC LOW WILL BE
QUICKLY EXITING OFF TO OUR NORTHEAST INTO EASTERN CANADA WITH ANY
LINGERING LIGHT SNOWS AND/OR MIXED PCPN GENERALLY ENDING BY NOON.
ANY BACK END ACCUMULATIONS SHOULD BE LIGHT. THE SYSTEM`S SFC COLD
FRONT WILL BE IN THE PROCESS OF SWINGING THROUGH THE AREA...AND
BEHIND THIS BOUNDARY WINDS WILL TREND WEST TO NORTHWESTERLY BY
DAYS END. WITH SFC FRONTAL PASSAGE IN THE LATE MORNING THROUGH
MID-AFTERNOON HOURS...A NEAR NORMAL DIURNAL TEMPERATURE TREND IS
EXPECTED AS DAYTIME MAXES TOP OUT IN THE 35 TO 40 DEGREE RANGE FOR
MOST SPOTS.
THEREAFTER SENSIBLE WEATHER TRENDS QUIET AND SEASONABLE AS BROAD SFC
HIGH PRESSURE BUILDS INTO THE REGION BRIDGED ALOFT BY WESTERLY
ZONAL FLOW. THUS PRIOR IDEA OF CLEAR TO PTLY CLOUDY SKIES ALONG
WITH DRY AND COOLER WEATHER STILL LOOKS RIGHT ON TRACK. LOWS SUNDAY
NIGHT GENERALLY 10 TO 20 ABOVE...WITH HIGHS ON MONDAY 23 TO 30. DID
OPT TO TREND ON THE COLDER SIDE OF NUMERICAL GUIDANCE ON MIN TEMPS
MONDAY NIGHT WHEN CENTER OF 1030+ MB SFC HIGH BUILDS DIRECTLY ATOP
THE FORECAST AREA ALONG WITH IDEAL RADIATIVE EFFECTS. THIS WOULD
SUGGEST READINGS BOTTOMING OUT FROM 5 BELOW TO 5 ABOVE WITH
LOCALIZED COLDER SPOTS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 305 PM EST SATURDAY...THE LONG TERM FCST FOCUS IS WEDS INTO
THURS TIME PERIOD ASSOCIATED WITH POTENTIAL WINTER STORM. THE
LATEST 12Z NWP GUIDANCE AND BOTH 00Z AND 12Z ENSEMBLE DATA IN VERY
GOOD AGREEMENT...RESULTING IN ABOVE NORMAL CONFIDENCE FOR UPCOMING
SYSTEM. THE LATEST TRENDS DO SUPPORT A SLIGHTLY MORE SOUTHERN
TRACK...WHICH PLACES OUR CWA WELL ESTABLISHED IN THE COLD SECTOR
ALONG WITH LESS QPF/SNOWFALL.
LARGE SCALE SYNOPTIC SETUP SHOWS DIGGING MID/UPPER LVL TROF ACRS
THE INTER MOUNTAIN WEST WITH POTENT 5H VORT EJECTING INTO THE
CENTRAL PLAINS BY 12Z TUES. THIS WL HELP IN THE DEVELOPMENT OF SFC
LOW PRES ACRS THE MS VALLEY...WHILE A FAST CONFLUENT FLW ALOFT
CONTS ACRS THE EASTERN CONUS. SFC LOW PRES WL TRACK TWD THE OHIO
VALLEY BY 06Z WEDS...THEN NEAR PITTSBURGH PA BY 12Z WEDS AND NYC
BY WEDS EVENING. THIS SYSTEM WL HAVE PLENTY OF DEEP SUB-TROPICAL
MOISTURE TO WORK WITH AND A FAVORABLE DUAL JET STRUCTURE. LATEST
GUIDANCE SUPPORTS ABOVE NORMAL PWS BTWN 0.75" AND 1.25" ACRS THE
MID ATLANTIC STATES...WITH A SHARP NORTH TO SOUTH GRADIENT ACRS
OUR CWA. IN ADDITION...FAST MOVEMENT OF SYSTEM AND NO CLOSED 5H/7H
CIRCULATIONS WL PREVENT STORM FROM BEING A BLOCKBUSTER AND MORE OF
A MODERATE PREICP/SNOWFALL EVENT FOR WEDS INTO THURS. THE SHARP
THERMAL PACKING ACRS OUR CWA...INDICATES STRONG LOW TO MID LVL FGEN/WAA
FORCING ASSOCIATED WITH NOSE OF 40 TO 50 KNOT 85H JET AND RRQ OF
25H JET ACRS SOUTHERN CANADA. RESULTING IN A PERIOD OF DEEP LAYER
LIFT/MOISTURE...WITH GREATEST IMPACTS ACRS OUR CENTRAL/SOUTHERN CWA. VERY
EARLY INDICATIONS SUPPORT QPF RANGING FROM 0.25 INTERNATIONAL
BORDER TO 0.75" RUTLAND/WINDSOR COUNTIES...RESULTING IN ADVISORY
TYPE EVENT NEAR THE BORDER AND WARNINGS ACRS CENTRAL/SOUTHERN VT
ZNS. ANY SHIFT FURTHER NORTH OR SOUTH WOULD GREATLY IMPACT THE
AMOUNT OF QPF/SNOWFALL EXPECTED AND LLVL THERMAL PROFILES. WL CONT
TO MENTION CAT POPS FOR WEDS WITH THERMAL SOUNDINGS SUPPORTING ALL
SNOW FOR OUR ENTIRE CWA. SNOW WL TAPER OFF WEDS NIGHT INTO
THURSDAY WITH A BRIEF PERIOD OF UPSLOPE SNOW SHOWERS
POSSIBLE...BUT DRIER AIR ASSOCIATED WITH SFC HIGH PRES BUILDS INTO
OUR REGION. EXPECT NEAR NORMAL TEMPS FOR THE PERIOD WITH DAILY
HIGHS IN THE 20S AND LOWS IN THE SINGLE DIGITS/TEENS...EXCEPT BLW
NORMAL READINGS ON THURS/FRIDAY ASSOCIATED WITH LLVL CAA BEHIND
DEPARTING SFC LOW PRES. ANOTHER SYSTEM MAY IMPACT OUR REGION NEXT
WEEKEND AS ACTIVE STORM PATTERN DEVELOPS WITH POTENTIAL SYSTEMS
EVERY COUPLE OF DAYS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...PBG/BTV MVFR/IFR CONDITIONS FOR VIS TIL 06Z.
IFR CONDITIONS AT MPV BY 23Z AND MAINLY MVFR CONDITIONS
PREVAILING AT RUT AS BEST MOISTURE/LIFT IS NORTH OF THIS TAF SITE.
THE HEAVIER AND STEADIER PRECIP WL EXIT OUR TAF SITES BY 06Z FOR
MVFR/VFR WITH EXCEPTION OF SLK/MSS...WHICH WL CONT TO SEE PERIODS
OF -SN WITH IFR CONDITIONS PREVAILING. THINKING BL TEMPS WARM
ENOUGH AT PBG/BTV FOR A MIXTURE OF -RASN BY 06Z WITH VIS BTWN
3-5SM...ESPECIALLY AS BETTER LIFTS SHIFTS NORTH OF REGION. A
DEVELOPING SW JET OF 45 TO 55 KNOTS BTWN 2500 AND 3500 FT AGL WL
PRODUCE AREAS OF TURBULENCE...ESPECIALLY IN THE MTNS...WITH SOME
SFC WIND GUSTS TO 20 KNOTS POSSIBLE. SOME LLVL WS WL BE POSSIBLE
AT MSS WITH NE SFC FLW OF 10 KNTS...WHILE FLW ALOFT IS FROM THE
SW.
COLD FRNT SWEEPS ACRS OUR CWA BTWN 14Z-18Z SUNDAY WITH ANOTHER
BRIEF PERIOD OF PRECIP POSSIBLE WITH MVFR/IFR CONDITIONS AND A
WIND SHIFT TO THE W/NW.
OUTLOOK 00Z MONDAY THROUGH WEDNESDAY...SFC HIGH PRES WITH VFR
CONDITIONS WL PREVAIL FROM 00Z MONDAY THRU 06Z WEDS. NEXT SYSTEM
WITH WIDESPREAD SNOW AND IFR CONDITIONS WL IMPACT OUR TAF SITES BY
12Z WEDS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST SUNDAY FOR VTZ002>004-
006-007-016.
NY...WINTER WEATHER ADVISORY UNTIL 11 AM EST SUNDAY FOR NYZ026>031-
034-087.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/WGH
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER/SLW
AREA FORECAST DISCUSSION
NWS RALEIGH NC
107 PM EST FRI JAN 31 2014
.SYNOPSIS...SURFACE HIGH PRESSURE REMAINS OVER THE REGION INTO
SATURDAY. WEAK LOW PRESSURE DEVELOPS ALONG THE CAROLINA COAST
SATURDAY...MOVING NORTHEAST ALONG THE COAST SATURDAY NIGHT AND EARLY
SUNDAY. A COLD FRONT MOVES ACROSS THE REGION FROM THE WEST SUNDAY
AND SUNDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM FRIDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SLACK GRADIENT OVER THE STATE
UNDER BROAD HIGH PRESSURE. THE 12Z UPPER-AIR ANALYSES WERE DRY AT
850MB...WITH BETTER 850MB MOISTURE LOCATED NOW JUST TO THE EAST OF
THE CENTRAL NORTH CAROLINA COASTAL PLAIN...AND DRY AT 700MB...WITH
HEIGHT RISES ALOFT AT 500MB. THERE WAS A WEAKNESS IN THE SOUTHWEST
FLOW ALOFT NOTED AT 250MB OVER THE GULF COAST...AND THIS COUPLED
WITH THE GOOD JET ALOFT TO OUR NORTHWEST WILL PRODUCE SOME MOSTLY
THIN HIGH CLOUDS IN CENTRAL NORTH CAROLINA THROUGH THE AFTERNOON.
THE LATEST RAP AND CANADIAN CLOUD COVER MODELS INDICATE THE HIGH
CLOUDS NUDGING WEST INTO SOUTHEAST GEORGIA AND SOUTHERN SOUTH
CAROLINA SHOULD GENERALLY STAY JUST TO THE SOUTHEAST OF KFAY AND
KCTZ...WHILE MORE NOTICEABLE HIGH CLOUDS WILL MOVE ACROSS MOST AREAS
ALONG AND NORTH OF ABOUT U.S. 64 PER THE LATEST VISIBLE SATELLITE
IMAGERY. THE LATEST VISIBLE IMAGES STILL SHOWED A LOT OF
TRANSPARENCY TO THE HIGH CLOUDS...BUT THERE SHOULD BE ENOUGH OF THEM
OVER PARTS OF THE NORTHWEST AND NORTHERN PIEDMONT TO RESULT IN A
PARTLY SUNNY SKY...OR SKIES BECOMING PARTLY SUNNY.
TEMPERATURES HAVE RISEN QUICKLY DURING THE MORNING...WITH MANY
OBSERVATIONS WELL INTO THE 20S AND EVEN CLOSE TO FREEZING AT 9 AM.
1000-850MB THICKNESSES FOR KGSO SUGGEST HIGHS INTO THE MID 50S...
BUT GIVEN THE LIMITED MIXING ON RAP SOUNDINGS AND THE GOOD INVERSION
PRESENT ON THE KGSO 12Z SOUNDING THINK THAT HIGH TEMPERATURES NEAR
THE COOLER GUIDANCE...OR A BLEND BETWEEN THE MAV AND MET...ARE
REASONABLE...AND ONLY SHADED TEMPERATURES UP FROM THE PREVIOUS
FORECAST MAYBE A DEGREE OR TWO BASED ON THE EARLY MORNING TRENDS.
THE MOST LIKELY ALTERNATIVE WOULD BE WARMER...AND WILL WATCH THE
OBSERVATIONS THROUGH THE REST OF THE MORNING. DEW POINTS WILL STAY
LOW...SO DESPITE THE WARMTH...SHADED AREAS WILL LIKELY STILL SHOW
ONLY A SLOW SNOW MELT.
THE FORECAST REMAINS DRY THROUGH TONIGHT. WITH MOSTLY CLEAR SKIES
AND CALM WINDS FOR A LARGE PART OF THE OVERNIGHT...POSSIBLY WITH A
RETURN OF SOME HIGH CLOUDS IN THE NORTHWEST PIEDMONT LATE CLOSER TO
THE UPPER JET...LOWS WILL BE DICTATED PRIMARILY BY RADIATIONAL
COOLING. WHERE SNOW COVER PERSISTS...THERE WILL BE SOME ENHANCED
RADIATIONAL COOLING AND LOWER MIN TEMPS. WILL CONTINUE TO SHOW LOWS
RANGING FROM THE UPPER TEENS TO MID 20S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 255 AM FRIDAY...
THE MODERATION IN TEMPERATURES WILL REALLY GET UNDERWAY ON SATURDAY.
THE MAIN SURFACE HIGH PRESSURE IS FORECAST TO MOVE OFF THE COAST.
HOWEVER... SURFACE RIDGING IS FORECAST TO EXTEND WESTWARD FROM THE
ATLANTIC BACK ACROSS NC/SC INTO SUNDAY AFTERNOON. AS THE WAA PATTERN
ALOFT RAMPS UP SATURDAY A RAPID INCREASE IN CLOUDS IS EXPECTED FROM
THE SOUTH. THIS SHOULD LIMIT THE TEMPERATURE RECOVERY SATURDAY.
HIGHS ARE STILL EXPECTED TO REACH INTO THE 50S (POSSIBLY MAY TOUCH
60 IN THE SOUTH) LATE. VERY MILD AIR WILL ADVECT ACROSS THE SE AND
MID-ATLANTIC STATES SATURDAY NIGHT AND SUNDAY. THIS WILL OCCUR OUT
AHEAD OF THE NEXT COLD FRONT THAT IS EXPECTED TO APPROACH THE REGION
LATE SUNDAY. A GOOD PART OF SUNDAY MAY TURN OUT TO BE DRY AND WARM.
HOWEVER... THE CHANCE OFF SHOWERS WILL INCREASE DURING THE AFTERNOON
FROM THE SOUTHWEST. EXPECT MOSTLY CLOUDY SKIES SATURDAY NIGHT
BECOMING PARTY SUNNY SUNDAY. THEN OVERCAST CONDITIONS ARE EXPECTED
TO ARRIVE WITH A CHANCE OF SHOWERS IN THE PIEDMONT DURING THE
AFTERNOON. LOWS IN THE 40S. HIGHS SUNDAY IN THE 60S EXCEPT 55-60 NW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 AM FRIDAY...
IT APPEARS THAT THE TREND IN THE MODELS CONTINUES TO BE WARMER WITH
THE SUNDAY NIGHT INTO MONDAY TIME FRAME AS THE NEXT SYSTEM IS
FORECAST TO TRACK NE THROUGH CENTRAL NC MONDAY. THIS WOULD PLACE
MUCH OF THE REGION IN THE SYSTEMS WARM SECTOR SUNDAY NIGHT THROUGH
THE LOW PRESSURES PASSAGE MONDAY. THE FAVORED NW PIEDMONT MAY REMAIN
IN A CAD PATTERN. IN ADDITION... THE MOST WIDESPREAD AND SIGNIFICANT
RAIN IS EXPECTED TO FALL ALONG AND LEFT (NORTHWEST) OF THE LOW
TRACK. THIS WOULD PLACE THE NW PIEDMONT IN THE HIGHEST QPF (0.50 TO
1 INCH) WITH LESSER AMOUNTS (TO LESS THAN 0.25) IN THE SE COASTAL
PLAIN FOR THE STORM TOTALS. THESE WARMER TRENDS ALSO STRONGLY FAVOR
ALL RAIN WITH THIS SYSTEM. IN FACT... THERE MAY EVEN BE A CHANCE OF
ISOLATED THUNDERSTORMS ALONG THE TRACK OF THE WAVE ON MONDAY.
THEREFORE... RAIN IS LIKELY IN THE WEST SUNDAY NIGHT INTO MONDAY
MORNING. THERE IS A CHANCE OF SHOWERS IN THE EAST. LOWS 35-40 NW...
RANGING TO NEAR 50 SE. HIGHS MONDAY IN THE 40S NW RANGING TO NEAR 60
SE.
THE PATTERN IS EXPECTED TO STAY VERY ACTIVE THROUGH THE WEEK WITH
TEMPERATURES BECOMING PROGRESSIVELY COLDER WITH THE PASSAGE OF EACH
STORM SYSTEM. THE NEXT SYSTEM IS EXPECTED TO LIFT FROM THE WESTERN
GULF INTO THE LOWER MISSISSIPPI VALLEY TUESDAY... THEN NORTHEAST
THROUGH THE TN AND OH VALLEY REGIONS BY 12Z/WED. THIS SYSTEM SHOULD
BE ACCOMPANIED BY AMPLE MOISTURE FROM THE GULF AND ATLANTIC WITH
ANOTHER SIGNIFICANT RAIN EVENT EXPECTED FOR MUCH OF NC. MODELS
CONTINUE TO INDICATE THE POTENTIAL FOR A HYBRID CAD EVENT IN THE
FAVORED PIEDMONT REGION TUE NIGHT INTO WED DRIVEN BY A PARENT
SURFACE HIGH PRESSURE OF 1032+ MB OVER NEW ENGLAND 12Z/TUE. THE HIGH
IS FORECAST TO PROGRESSIVELY MOVE OFFSHORE AS THE STORM LIFTS UP
THROUGH THE TN VALLEY TUE NIGHT. THIS PATTERN STRONGLY SUGGESTS CAD
BREAKING IN THE COASTAL PLAIN TUE NIGHT WITH A STRONG CAD BOUNDARY
LIKELY DEVELOPING AND PERSISTING INTO WEDNESDAY OVER THE PIEDMONT. P-
TYPE CONCERNS SHOULD BE LIMITED TO THE NW AND NORTH-CENTRAL PIEDMONT
TUESDAY - WITH THE MAIN HAZARD EXPECTED TO BE A CHANCE OF LIGHT
FREEZING RAIN AT THE PRECIPITATION ONSET. CURRENT LOW LEVEL
THICKNESS FORECASTS AND FORECAST TEMPERATURE PROFILES ARGUE FOR
WARMING ALOFT AND A DEVELOPING POTENTIAL FOR RESIDUAL COLD AIR AT
THE SURFACE WITH TEMPS POSSIBLY 30-32 AT THE ONSET IN THE TRIAD TO
ROXBORO TUESDAY. THERE ARE A LOT OF IFS AT THE CURRENT TIME (A
COUPLE OF WHICH INCLUDE TIMING OF PRECIP ONSET AND HOW MUCH COLD AIR
WILL DRAIN INTO THE REGION COURTESY OF THE HIGH PRESSURE INITIALLY.
THEREFORE... FORECAST CONFIDENCE IS LOW FOR FREEZING RAIN... BUT
HIGH FOR RAIN DURING THIS EVENT. STAY TUNED. FOR NOW... WE WILL
MAINTAIN THE ALL LIQUID FORECAST WITH LOWS 30-35 TUE AND HIGHS 36-
50. INCREASING CHANCE OF RAIN TUESDAY INTO WED. LOWS WED 36-48.
HIGHS WEDNESDAY 45 NW TO 68 SE.
THE ACTIVE PATTERN GETS EVEN MORE INTERESTING LATER IN THE WEEK.
ANOTHER ARCTIC HIGH IS FORECAST TO PUSH FORM THE PLAINS AND MIDWEST
TOWARD NEW ENGLAND THU-FRI. THE MAIN MID/UPPER TROUGH IS EXPECTED TO
HANG BACK OVER THE PLAINS. A SPLIT FLOW PATTERN WITH AN ACTIVE STORM
TRACK ACROSS THE SOUTH IS EXPECTED. IT IS UNCLEAR HOW FAR SOUTH THE
VERY COLD AIR WILL BE ABLE TO PENETRATE INTO OUR REGION COURTESY OF
LINGERING UPPER RIDGING OVER FL/GA. HOWEVER... SOME MODELS SUGGEST A
POTENTIAL FOR CLASSICAL CAD BY FRIDAY OUT AHEAD OF A LARGE STORM
SYSTEM THAT SHOULD DEVELOP OVER THE WESTERN GULF HEADED NE. THIS IS
THE SYSTEM TO WATCH AS THE PIEDMONT OR MOUNTAINS WOULD BE FAVORED
FOR P-TYPE ISSUES IN SUCH A PATTERN IF CLASSICAL CAD DEVELOPS DOWN
THE EASTERN SEABOARD. FOR NOW... WE WILL CARRY PARTLY CLOUDY SKIES
THURSDAY. COLDER WITH HIGHS IN THE 40S. INCREASING CLOUDINESS
THURSDAY NIGHT WITH LOWS IN THE 20S. CLOUDY FRIDAY. A CHANCE OF
RAIN. WE WILL OMIT THE CHANCE OF SNOW OR FREEZING RAIN FOR NOW DUE
TO HIGH UNCERTAINTY IN THE TIMING AND AMOUNT OF COLD AIR AND THE
TIMING OF PRECIP. HIGHS 30S NW TO 40S SE.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 105 PM FRIDAY...
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE 18Z VALID TAF
PERIOD. THE SREF PROBABILISTIC GUIDANCE SUGGESTS THE POTENTIAL FOR
SOME LOW CLOUDS AND/OR FOG IN THE NORTHWEST PIEDMONT LATE TONIGHT
AND EARLY SATURDAY...BUT THE SURFACE DEW POINT FORECAST FROM THAT
MODEL SEEMS SO HIGH...ESPECIALLY COMPARING THE MODEL FORECAST WITH
CURRENT CONDITIONS...THAT IT IS DIFFICULT TO FOLLOW THAT GUIDANCE.
THERE IS A LITTLE MOIST ADVECTION LATE TONIGHT TOWARD KFAY AND
KCTZ...AND WHILE LEFT THE TAF THERE VFR FOR NOW...AND GUIDANCE IS
ALL VFR...CANNOT COMPLETELY RULE OUT SOME LOWER AVIATION CONDITIONS
TOWARD THERE LATE TONIGHT AND EARLY SATURDAY. OTHERWISE...HIGH
CLOUDS AND A LIGHT SOUTH TO SOUTHWEST WIND THIS AFTERNOON BECOMES
LIGHT AND VARIABLE THIS EVENING...WITH A LIGHT FLOW AGAIN SATURDAY
WITH SURFACE WINDS IN THE EAST-TO-SOUTH QUADRANT OF THE CIRCLE BY
SATURDAY AFTERNOON.
BEYOND THE 18Z VALID TAF PERIOD...SATURDAY NIGHT INTO SUNDAY...IN A
MOIST AIR MASS...THINK THERE IS A HIGH PROBABILITY OF SUB-VFR
CONDITIONS IN LOW CLOUDS AND/OR FOG. CONDITIONS SHOULD IMPROVE
DURING SUNDAY...THEN LATE SUNDAY NIGHT AND MONDAY SUB-VFR CONDITIONS
RETURN AGAIN BEHIND A COLD FRONT. THERE IS A SLIGHT CHANCE FOR A
PERIOD OF FREEZING PRECIPITATION LATE MONDAY NIGHT INTO EARLY
TUESDAY IN THE NORTHWEST PIEDMONT. SUB-VFR CONDITIONS LIKELY PERSIST
OVERALL FROM MONDAY INTO WEDNESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/VINCENT
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
942 AM EST FRI JAN 31 2014
.SYNOPSIS...A RELATIVELY WARM AND MOIST SOUTHERLY RETURN FLOW WILL
PREVAIL THROUGH THE WEEKEND AS A COLD FRONT SLOWLY APPROACHES THE
REGION FROM THE WEST. A LOW PRESSURE SYSTEM WILL DEVELOP ALONG THE
FRONT OVER THE DEEP SOUTH SUNDAY AFTERNOON...THEN TRACK NORTHEAST
THROUGH THE CAROLINAS AND VIRGINIA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM FRIDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SLACK GRADIENT OVER THE STATE
UNDER BROAD HIGH PRESSURE. THE 12Z UPPER-AIR ANALYSES WERE DRY AT
850MB...WITH BETTER 850MB MOISTURE LOCATED NOW JUST TO THE EAST OF
THE CENTRAL NORTH CAROLINA COASTAL PLAIN...AND DRY AT 700MB...WITH
HEIGHT RISES ALOFT AT 500MB. THERE WAS A WEAKNESS IN THE SOUTHWEST
FLOW ALOFT NOTED AT 250MB OVER THE GULF COAST...AND THIS COUPLED
WITH THE GOOD JET ALOFT TO OUR NORTHWEST WILL PRODUCE SOME MOSTLY
THIN HIGH CLOUDS IN CENTRAL NORTH CAROLINA THROUGH THE AFTERNOON.
THE LATEST RAP AND CANADIAN CLOUD COVER MODELS INDICATE THE HIGH
CLOUDS NUDGING WEST INTO SOUTHEAST GEORGIA AND SOUTHERN SOUTH
CAROLINA SHOULD GENERALLY STAY JUST TO THE SOUTHEAST OF KFAY AND
KCTZ...WHILE MORE NOTICEABLE HIGH CLOUDS WILL MOVE ACROSS MOST AREAS
ALONG AND NORTH OF ABOUT U.S. 64 PER THE LATEST VISIBLE SATELLITE
IMAGERY. THE LATEST VISIBLE IMAGES STILL SHOWED A LOT OF
TRANSPARENCY TO THE HIGH CLOUDS...BUT THERE SHOULD BE ENOUGH OF THEM
OVER PARTS OF THE NORTHWEST AND NORTHERN PIEDMONT TO RESULT IN A
PARTLY SUNNY SKY...OR SKIES BECOMING PARTLY SUNNY.
TEMPERATURES HAVE RISEN QUICKLY DURING THE MORNING...WITH MANY
OBSERVATIONS WELL INTO THE 20S AND EVEN CLOSE TO FREEZING AT 9 AM.
1000-850MB THICKNESSES FOR KGSO SUGGEST HIGHS INTO THE MID 50S...
BUT GIVEN THE LIMITED MIXING ON RAP SOUNDINGS AND THE GOOD INVERSION
PRESENT ON THE KGSO 12Z SOUNDING THINK THAT HIGH TEMPERATURES NEAR
THE COOLER GUIDANCE...OR A BLEND BETWEEN THE MAV AND MET...ARE
REASONABLE...AND ONLY SHADED TEMPERATURES UP FROM THE PREVIOUS
FORECAST MAYBE A DEGREE OR TWO BASED ON THE EARLY MORNING TRENDS.
THE MOST LIKELY ALTERNATIVE WOULD BE WARMER...AND WILL WATCH THE
OBSERVATIONS THROUGH THE REST OF THE MORNING. DEW POINTS WILL STAY
LOW...SO DESPITE THE WARMTH...SHADED AREAS WILL LIKELY STILL SHOW
ONLY A SLOW SNOW MELT.
THE FORECAST REMAINS DRY THROUGH TONIGHT. WITH MOSTLY CLEAR SKIES
AND CALM WINDS FOR A LARGE PART OF THE OVERNIGHT...POSSIBLY WITH A
RETURN OF SOME HIGH CLOUDS IN THE NORTHWEST PIEDMONT LATE CLOSER TO
THE UPPER JET...LOWS WILL BE DICTATED PRIMARILY BY RADIATIONAL
COOLING. WHERE SNOW COVER PERSISTS...THERE WILL BE SOME ENHANCED
RADIATIONAL COOLING AND LOWER MIN TEMPS. WILL CONTINUE TO SHOW LOWS
RANGING FROM THE UPPER TEENS TO MID 20S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 255 AM FRIDAY...
THE MODERATION IN TEMPERATURES WILL REALLY GET UNDERWAY ON SATURDAY.
THE MAIN SURFACE HIGH PRESSURE IS FORECAST TO MOVE OFF THE COAST.
HOWEVER... SURFACE RIDGING IS FORECAST TO EXTEND WESTWARD FROM THE
ATLANTIC BACK ACROSS NC/SC INTO SUNDAY AFTERNOON. AS THE WAA PATTERN
ALOFT RAMPS UP SATURDAY A RAPID INCREASE IN CLOUDS IS EXPECTED FROM
THE SOUTH. THIS SHOULD LIMIT THE TEMPERATURE RECOVERY SATURDAY.
HIGHS ARE STILL EXPECTED TO REACH INTO THE 50S (POSSIBLY MAY TOUCH
60 IN THE SOUTH) LATE. VERY MILD AIR WILL ADVECT ACROSS THE SE AND
MID-ATLANTIC STATES SATURDAY NIGHT AND SUNDAY. THIS WILL OCCUR OUT
AHEAD OF THE NEXT COLD FRONT THAT IS EXPECTED TO APPROACH THE REGION
LATE SUNDAY. A GOOD PART OF SUNDAY MAY TURN OUT TO BE DRY AND WARM.
HOWEVER... THE CHANCE OFF SHOWERS WILL INCREASE DURING THE AFTERNOON
FROM THE SOUTHWEST. EXPECT MOSTLY CLOUDY SKIES SATURDAY NIGHT
BECOMING PARTY SUNNY SUNDAY. THEN OVERCAST CONDITIONS ARE EXPECTED
TO ARRIVE WITH A CHANCE OF SHOWERS IN THE PIEDMONT DURING THE
AFTERNOON. LOWS IN THE 40S. HIGHS SUNDAY IN THE 60S EXCEPT 55-60 NW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 AM FRIDAY...
IT APPEARS THAT THE TREND IN THE MODELS CONTINUES TO BE WARMER WITH
THE SUNDAY NIGHT INTO MONDAY TIME FRAME AS THE NEXT SYSTEM IS
FORECAST TO TRACK NE THROUGH CENTRAL NC MONDAY. THIS WOULD PLACE
MUCH OF THE REGION IN THE SYSTEMS WARM SECTOR SUNDAY NIGHT THROUGH
THE LOW PRESSURES PASSAGE MONDAY. THE FAVORED NW PIEDMONT MAY REMAIN
IN A CAD PATTERN. IN ADDITION... THE MOST WIDESPREAD AND SIGNIFICANT
RAIN IS EXPECTED TO FALL ALONG AND LEFT (NORTHWEST) OF THE LOW
TRACK. THIS WOULD PLACE THE NW PIEDMONT IN THE HIGHEST QPF (0.50 TO
1 INCH) WITH LESSER AMOUNTS (TO LESS THAN 0.25) IN THE SE COASTAL
PLAIN FOR THE STORM TOTALS. THESE WARMER TRENDS ALSO STRONGLY FAVOR
ALL RAIN WITH THIS SYSTEM. IN FACT... THERE MAY EVEN BE A CHANCE OF
ISOLATED THUNDERSTORMS ALONG THE TRACK OF THE WAVE ON MONDAY.
THEREFORE... RAIN IS LIKELY IN THE WEST SUNDAY NIGHT INTO MONDAY
MORNING. THERE IS A CHANCE OF SHOWERS IN THE EAST. LOWS 35-40 NW...
RANGING TO NEAR 50 SE. HIGHS MONDAY IN THE 40S NW RANGING TO NEAR 60
SE.
THE PATTERN IS EXPECTED TO STAY VERY ACTIVE THROUGH THE WEEK WITH
TEMPERATURES BECOMING PROGRESSIVELY COLDER WITH THE PASSAGE OF EACH
STORM SYSTEM. THE NEXT SYSTEM IS EXPECTED TO LIFT FROM THE WESTERN
GULF INTO THE LOWER MISSISSIPPI VALLEY TUESDAY... THEN NORTHEAST
THROUGH THE TN AND OH VALLEY REGIONS BY 12Z/WED. THIS SYSTEM SHOULD
BE ACCOMPANIED BY AMPLE MOISTURE FROM THE GULF AND ATLANTIC WITH
ANOTHER SIGNIFICANT RAIN EVENT EXPECTED FOR MUCH OF NC. MODELS
CONTINUE TO INDICATE THE POTENTIAL FOR A HYBRID CAD EVENT IN THE
FAVORED PIEDMONT REGION TUE NIGHT INTO WED DRIVEN BY A PARENT
SURFACE HIGH PRESSURE OF 1032+ MB OVER NEW ENGLAND 12Z/TUE. THE HIGH
IS FORECAST TO PROGRESSIVELY MOVE OFFSHORE AS THE STORM LIFTS UP
THROUGH THE TN VALLEY TUE NIGHT. THIS PATTERN STRONGLY SUGGESTS CAD
BREAKING IN THE COASTAL PLAIN TUE NIGHT WITH A STRONG CAD BOUNDARY
LIKELY DEVELOPING AND PERSISTING INTO WEDNESDAY OVER THE PIEDMONT. P-
TYPE CONCERNS SHOULD BE LIMITED TO THE NW AND NORTH-CENTRAL PIEDMONT
TUESDAY - WITH THE MAIN HAZARD EXPECTED TO BE A CHANCE OF LIGHT
FREEZING RAIN AT THE PRECIPITATION ONSET. CURRENT LOW LEVEL
THICKNESS FORECASTS AND FORECAST TEMPERATURE PROFILES ARGUE FOR
WARMING ALOFT AND A DEVELOPING POTENTIAL FOR RESIDUAL COLD AIR AT
THE SURFACE WITH TEMPS POSSIBLY 30-32 AT THE ONSET IN THE TRIAD TO
ROXBORO TUESDAY. THERE ARE A LOT OF IFS AT THE CURRENT TIME (A
COUPLE OF WHICH INCLUDE TIMING OF PRECIP ONSET AND HOW MUCH COLD AIR
WILL DRAIN INTO THE REGION COURTESY OF THE HIGH PRESSURE INITIALLY.
THEREFORE... FORECAST CONFIDENCE IS LOW FOR FREEZING RAIN... BUT
HIGH FOR RAIN DURING THIS EVENT. STAY TUNED. FOR NOW... WE WILL
MAINTAIN THE ALL LIQUID FORECAST WITH LOWS 30-35 TUE AND HIGHS 36-
50. INCREASING CHANCE OF RAIN TUESDAY INTO WED. LOWS WED 36-48.
HIGHS WEDNESDAY 45 NW TO 68 SE.
THE ACTIVE PATTERN GETS EVEN MORE INTERESTING LATER IN THE WEEK.
ANOTHER ARCTIC HIGH IS FORECAST TO PUSH FORM THE PLAINS AND MIDWEST
TOWARD NEW ENGLAND THU-FRI. THE MAIN MID/UPPER TROUGH IS EXPECTED TO
HANG BACK OVER THE PLAINS. A SPLIT FLOW PATTERN WITH AN ACTIVE STORM
TRACK ACROSS THE SOUTH IS EXPECTED. IT IS UNCLEAR HOW FAR SOUTH THE
VERY COLD AIR WILL BE ABLE TO PENETRATE INTO OUR REGION COURTESY OF
LINGERING UPPER RIDGING OVER FL/GA. HOWEVER... SOME MODELS SUGGEST A
POTENTIAL FOR CLASSICAL CAD BY FRIDAY OUT AHEAD OF A LARGE STORM
SYSTEM THAT SHOULD DEVELOP OVER THE WESTERN GULF HEADED NE. THIS IS
THE SYSTEM TO WATCH AS THE PIEDMONT OR MOUNTAINS WOULD BE FAVORED
FOR P-TYPE ISSUES IN SUCH A PATTERN IF CLASSICAL CAD DEVELOPS DOWN
THE EASTERN SEABOARD. FOR NOW... WE WILL CARRY PARTLY CLOUDY SKIES
THURSDAY. COLDER WITH HIGHS IN THE 40S. INCREASING CLOUDINESS
THURSDAY NIGHT WITH LOWS IN THE 20S. CLOUDY FRIDAY. A CHANCE OF
RAIN. WE WILL OMIT THE CHANCE OF SNOW OR FREEZING RAIN FOR NOW DUE
TO HIGH UNCERTAINTY IN THE TIMING AND AMOUNT OF COLD AIR AND THE
TIMING OF PRECIP. HIGHS 30S NW TO 40S SE.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
AS OF 940 AM FRIDAY...
THROUGH THE 24-HR TAF PERIOD...EXPECT VFR CONDITIONS WITH HIGH
CLOUDS MAINLY OVER THE NORTHWEST AND NORTHERN PIEDMONT INTO TONIGHT.
LOOKING AHEAD...ADVERSE AVIATION CONDITIONS IN THE FORM OF MVFR/IFR
CEILINGS ARE EXPECTED TO DEVELOP LATE SAT AND SAT NIGHT IN
ASSOCIATION WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW IN
ADVANCE OF A COLD FRONT SLOWLY APPROACHING THE REGION FROM THE WEST.
SOME IMPROVEMENT WILL BE POSSIBLE BY EARLY SUNDAY AFTERNOON...THOUGH
UNCERTAINTY IS ABOVE AVERAGE AND SUB-VFR CEILINGS MAY PERSIST. A
SERIES OF LOW PRESSURE SYSTEMS...THE FIRST SUN NIGHT/MON AND THE
SECOND TUE/TUE NIGHT...WILL DEVELOP ALONG THE LOWER MS RIVER VALLEY/
GULF COAST AND TRACK NORTHEAST ALONG OR JUST EAST OF THE
APPALACHIANS THROUGH MID NEXT WEEK. AS A RESULT...AN EXTENDED PERIOD
OF ADVERSE AVIATION CONDITIONS APPEARS LIKELY SUNDAY EVENING THROUGH
WEDNESDAY. VFR CONDITIONS SHOULD RETURN WED NIGHT/THU IN ASSOCIATION
WITH AN ARCTIC COLD FRONTAL PASSAGE.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF/VINCENT
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...DJF/VINCENT
AREA FORECAST DISCUSSION
NWS BISMARCK ND
217 PM CST FRI JAN 31 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 204 PM CST FRI JAN 31 2014
THE MAIN FORECAST ISSUE IN THE NEAR TERM PERIOD IS THE COLD
FRONTAL PASSAGE TONIGHT AND CONSIDERATION OF WIND CHILL HEADLINES.
RECENT OBS AND RADAR TRENDS INDICATE A NARROW BAND OF WEAK
REFLECTIVITY ALONG A COLD FRONT THAT HAS PUSHED INTO SOUTHERN
SASKATCHEWAN. THIS FRONT WILL CONTINUE TO PUSH SOUTHEAST THROUGH
THE FORECAST AREA TONIGHT. HI-RES MODELS SUCH AS THE HRRR AND 13KM
RAP ARE INDICATING SOME VERY LIGHT QPF. WILL MENTION SCATTERED
FLURRIES TONIGHT...TRENDING FROM THE NORTH THIS EVENING INTO THE
JAMES RIVER VALLEY LATE. NO ACCUMULATION IS EXPECTED. CLOUDS AND A
NORTHWEST WIND AT 10-15 MPH ARE EXPECTED TO KEEP TEMPS FROM
BOTTOMING OUT IN THE NORTH. AM EXPECTING WIND CHILLS OF 20 TO 25
BELOW ZERO IN THE NORTHERN TWO TIERS OF COUNTIES...NOT QUITE COLD
ENOUGH FOR AN ADVISORY. ON SATURDAY...DAYTIME TEMPERATURES ARE
ONLY EXPECTED TO RISE SLIGHTLY FROM THE MORNING LOWS AS THE COLD
POCKET SETTLES OVER NORTH DAKOTA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 204 PM CST FRI JAN 31 2014
SATURDAY NIGHT THROUGH FRIDAY...
SUCCESSIVE POCKETS OF COLD AIR/SHORTWAVES ROTATE THROUGH THE
PERSISTENT NORTHWEST FLOW ALOFT INTO NORTH DAKOTA. THE MAIN
HIGHLIGHT WILL BE THE COLD AIR WITH WIND CHILL HIGHLIGHTS LIKELY
HOISTED EACH NIGHT THROUGH THE LATE MORNING THROUGH THE EXTENDED PERIOD.
WIND CHILL ADVISORY CRITERIA LOOKS MORE LIKELY IN THE NORTH CENTRAL
AND EAST CENTRAL NORTH DAKOTA. WEDNESDAY MORNING AND THURSDAY
MORNING...WIND CHILL ADVISORY APPEARS MOST WIDESPREAD COVERING ALL
OF WESTERN AND CENTRAL NORTH DAKOTA. IT IS DURING THIS TIME THE
COLDEST SURGE OF H85 TEMPS ARRIVE...BETWEEN -24C TO -27C. WITH THAT
SAID...AFTER COLLABORATING WITH BILLINGS AND RAPID CITY...UNDERCUT
THE ALLBLEND LOW TEMPERATURES BY A FEW DEGREES TUESDAY THROUGH
THURSDAY MORNING. THERE COULD BE A LITTLE LIGHT SNOW IN THE FAR
SOUTHWEST MONDAY NIGHT INTO TUESDAY MORNING PRECEDING THE
AFOREMENTIONED SURGE OF FRIGID AIR. ELSEWHERE...COLD/FRIGID AIR
DOMINATES WITH DRY CONDITIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 204 PM CST FRI JAN 31 2014
A COLD FRONT WILL PUSH SOUTHEAST THROUGH NORTH DAKOTA TONIGHT.
EXPECT A SHIFT TO A NORTHWEST WIND WITH FROPA...ALONG WITH MAINLY
MVFR STRATUS AROUND 2000 FT AGL. THESE CEILINGS ARE EXPECTED AT
KISN/KDIK AROUND 03Z...KMOT AROUND 04Z...KBIS AROUND 07Z AND
FINALLY KJMS AROUND 11Z SATURDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM/AVIATION...RP KINNEY
LONG TERM...KS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1058 PM EST SAT FEB 1 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT. LOW PRESSURE TRACKING
ALONG THIS FRONT WILL PASS SOUTH OF THE AREA SUNDAY AFTERNOON AND
NIGHT. ANOTHER LOW PRESSURE SYSTEM WILL IMPACT THE REGION LATE
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
COLD FRONT IS JUST MOVING INTO THE FORECAST AREA AND WILL CONTINUE
SOUTHEAST THROUGH THE NIGHT. SHOWERS HAVE BEEN SLOWLY
OVERSPREADING THE AREA AND WILL COVER THE ENTIRE REGION BEFORE THE
NIGHT IS OVER. AS COLDER AIR BECOMES DEEPER RAIN WILL CHANGE TO
SNOW. HAVE ONCE AGAIN DELAYED THIS TRANSITION BY A FEW HOURS SO
THIS WILL MOSTLY AFFECT AREAS FROM DAYTON TO THE NORTH AND WEST
OVERNIGHT. RECENT RAP AND NAM RUNS ARE INDICATING A BAND
STRETCHING ACROSS WEST CENTRAL OHIO AND SO THERE IS SOME CONCERN
THAT MORE SUBSTANTIAL ACCUMULATIONS COULD OCCUR THERE. AT THIS
POINT FORECAST IS FOR BELOW ADVISORY AMOUNTS. BUT THIS IS
SOMETHING THAT WILL HAVE TO BE MONITORED AS THE NIGHT PROGRESSES.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
PRECIPITATION WILL BE ONGOING AT THE BEGINNING OF THE PERIOD BUT
THEN RAPIDLY END DURING THE MORNING AS THE INITIAL SHORT WAVE
MOVES OFF TO THE EAST. CHANGE IN PRECIPITATION TYPE WILL CONTINUE
TO PROGRESS SOUTHEAST DURING THIS TIME FRAME. ONLY LIGHT
ADDITIONAL ACCUMULATIONS ARE EXPECTED. BUT THERE IS AT LEAST SOME
POTENTIAL FOR A PERIOD OF FREEZING RAIN DURING THE TRANSITION.
ZONAL SOUTHWEST FLOW ALOFT WILL KEEP THE MOISTURE FEED THROUGH
THE STATE OF KY INTO WV IN A SW-NE ORIENTATION...EVEN AS THE
SURFACE FRONT DIVES WELL PAST THESE STATES. THE COLD AIR
UNDERCUTTING THIS STRONG LINGERING MOISTURE FEED HAS INCREASED THE
THREAT FOR SIGNIFICANT ACCUMULATING SNOWFALL IN OUR SOUTHEASTERN
CWA. WHILE THE NAM REMAINS A VERY DRY OUTLIER...THE LATEST
EUROPEAN HELPS CONFIRM THAT DEEP MOISTURE WILL STILL BE PRESENT
DURING THE 6-12Z TIME FRAME SUN NIGHT BEFORE THE DRIER AIR WORKS
IN ON NORTH WINDS. A SMALL SHORTWAVE WITH STRONGER DYNAMICS WILL
CROSS THE SOUTHERN CWA AT H5 AROUND 12Z MONDAY AND HELP END ANY
THREAT FOR SNOWFALL IN A RAPID FASHION.
THE SURFACE HIGH OVER THE UPPER MIDWEST WILL MEANDER EAST ACROSS
THE NORTHERN OHIO VALLEY/SOUTHERN GREAT LAKES AND PROVIDE FOR A
BREAK BETWEEN SYSTEMS. EXPECT CLOUD COVER TO DROP OFF AND
TEMPERATURES TO REMAIN ON THE COOL SIDE FOR MONDAY AND MONDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MAIN FOCUS OF THE LONG TERM PERIOD WAS TO ANALYZE THE LOW
PRESSURE SYSTEM WHICH WILL AFFECT THE AREA LATE TUESDAY INTO EARLY
WEDNESDAY. HIGH PRESSURE WILL BE DEPARTING TUESDAY MORNING AS A
SOUTHERN STREAM SHORT WAVE TROUGH EJECTS FROM THE DESERT SOUTHWEST.
THIS WILL ORGANIZE A LOW PRESSURE SYSTEM OVER THE LOWER MISSISSIPPI
VALLEY WHICH WILL TRACK UP THE WESTERN SIDE OF THE APPALACHIANS
TUESDAY NIGHT. AS HAS BEEN DISCUSSED THE PAST FEW DAYS...THE TRACK
AND STRENGTH OF THIS SYSTEM WILL MEAN EVERYTHING IN TERMS OF
PRECIPITATION TYPE AND AMOUNTS IN OUR FORECAST AREA.
ITS STILL MUCH TOO EARLY TO FRET OVER EACH MODEL AND ITS RESPECTIVE
RUN AS THE TRACK OF THE LOW HAS BEEN SHIFTING ON THE ORDER OF 30-60
MILES. OF THE 12Z SOLUTIONS...THE CANADIAN CAME IN THE COLDEST...BUT
DPROG/DT ANALYSIS SUGGESTS IT HAS BEEN THE MOST ERRATIC MODEL AND IT
WAS THUSLY DISCOUNTED. OTHERWISE THE MODELS SEEM TO BE ZEROING IN ON
A TRACK PARALLEL BUT SOUTHEAST OF I-71. AN ANALYSIS OF THERMAL
PROFILES SUGGESTS MOSTLY SNOW IN OUR NORTHWESTERN COUNTIES IN WEST
CENTRAL OHIO...AND A MOSTLY RAIN IN SOUTH CENTRAL OHIO AND NORTHEAST
KENTUCKY. IN BETWEEN IS WHERE IT GETS TRICKY...AND FRANKLY ALL
PRECIPITATION TYPES WILL BE IN PLAY. PERSISTENT NORTHEASTERLY
SURFACE FLOW COMBINED WITH A WARM NOSE ALOFT MEANS THAT ICE
ACCUMULATIONS COULD BE NOTABLE IN THE TRANSITION ZONE. AS THE SREF
TRICKLES IN...IT ALSO SUPPORTS AN I-71 TRANSITION ZONE...WITH
PROBABILITIES OF ACCUMULATING SNOW DECREASING IN THIS AREA. MODEL
QPF FIELDS SUGGEST A RANGE FROM 0.6 TO 2.0 INCHES. THUS SIGNIFICANT
WINTRY ACCUMULATIONS WILL BE POSSIBLE FOR PARTS OF THE AREA AND ITS
NOT OUT OF THE QUESTION THERE COULD BE SOME MINOR FLOODING CONCERNS
IN THE SOUTH. WITH INCREASING CONFIDENCE IN THE
SITUATION...ADDITIONAL DETAILS WERE ADDED TO THE GRIDS TO REPRESENT
THE FULL MIXED BAG OF PTYPES. AT THIS TIME TEMPERATURES GENERALLY
FOLLOW THE BLEND OF RAW MODELS...WHICH CAPTURES THE BASIC
IDEA...ALTHOUGH THE GRADIENT COULD BE MUCH TIGHTER DEPENDING ON THE
LOW TRACK AND HOW MUCH WARM AIR IS PULLED NORTHWARD. THIS IS
DEFINITELY A /STAY TUNED/ TYPE OF WEATHER SYSTEM AND WILL CONTINUE
TO BE MENTIONED IN THE HWO.
ON WEDNESDAY...POPS WERE DECREASED MUCH FASTER THAN THE PREVIOUS
FORECAST AS DRIER AIR PUSHES INTO THE AREA. SOME LIGHT SNOW MAY
LINGER GENERALLY NORTH OF I-70 IN THE CYCLONIC FLOW. TEMPERATURES
WILL REMAIN STEADY OR FALL THROUGH THE DAY. THURSDAY AND FRIDAY WILL
BE TRANQUIL BUT COLD AS HIGH PRESSURE BUILDS IN. THURSDAY NIGHT WILL
BE THE COLDEST AS THE CENTER OF HIGH PRESSURE MOVES OVERHEAD. SOME
BELOW ZERO LOWS ARE SUPPORTED IN WEST CENTRAL OHIO. A RETURN OF
MOISTURE IS SHOWN FOR FRIDAY NIGHT INTO SATURDAY.
HOWEVER...OPERATIONAL AND ENSEMBLE MODEL SPREAD IS QUITE HIGH.
INTRODUCED CHANCE POPS WITH A RAIN/SNOW MIXTURE ACROSS THE
AREA...WHICH WILL BE DEPENDENT ON HOW THE SYSTEMS TRACK.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS TO START THE PERIOD WILL START TO DETERIORATE AS
SHOWERS SPREAD ACROSS THE TERMINALS. EXPECT TO ONLY FALL TO MVFR
INITIALLY. BUT AS A COLD FRONT MOVES THROUGH CEILINGS SHOULD DROP
TO IFR. SEVERAL HOURS AFTER FRONTAL PASSAGE PRECIPITATION WILL
TRANSITION OVER TO SNOW. CANNOT COMPLETELY RULE OUT A BRIEF PERIOD
OF FREEZING RAIN DURING THE CHANGE OVER. BUT PROBABILITY IS NOT
HIGH ENOUGH FOR INCLUSION IN THE TAFS. SNOW WILL DROP VISIBILITY
TO IFR AS WELL WITH LIGHT ACCUMULATIONS POSSIBLE AT ALL TAF SITES.
VISIBILITIES WILL IMPROVE AS SNOW COMES TO AN END BUT CEILINGS
WILL BE STUBBORN. MAY SEE CEILINGS EVENTUALLY LIFT BACK TO MVFR
LATE IN THE TAF PERIOD. THERE IS SOME POTENTIAL FOR PRECIPITATION
TO CONTINUE NEAR THE CINCINNATI TERMINALS LATE IN THE PERIOD. BUT
FELT THE HIGHER PROBABILITY WAS FOR IT TO STAY SOUTH AT THIS
POINT.
OUTLOOK...MVFR CEILINGS WILL LIKELY PERSIST SUNDAY NIGHT INTO
MONDAY MORNING. MVFR TO IFR CEILINGS AND VISIBILITIES LIKELY WITH
A WINTRY MIX OF PRECIPITATION LATE TUESDAY INTO WEDNESDAY MORNING.
MVFR CEILINGS AND VISIBILITIES MAY LINGER INTO WEDNESDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
MORNING FOR OHZ079-081-082-088.
KY...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
MORNING FOR KYZ094>100.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...FRANKS
LONG TERM...SNYDER
AVIATION...
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1254 PM EST FRI JAN 31 2014
.SYNOPSIS...
FRONT STALLS IN OHIO VALLEY WITH LOW PRESSURE WAVE MOVING ALONG
IT SATURDAY. MUCH MILDER SATURDAY. COLD FRONT BRINGS MAINLY RAIN
SATURDAY NIGHT THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
SENT AN UPDATE TO INCREASE HIGHS TEMPERATURES FOR THIS AFTERNOON
AS A NON DIURNAL TREND WAS NOTICED OVERNIGHT AND IT WAS 40 DEGREES
ALREADY AT 1030 AM. USED SFC OBS AND LAV GUIDANCE FOR HIGHS TODAY.
POPULATED WIND FROM THE RAP HIGH RESOLUTION MODEL. ADJUSTED SKY
GRIDS STARTING WITH LATEST IR SATELLITE IMAGES EXTRAPOLATING WITH
NAM WINDS AND BLENDING WITH THE CMC MODEL CLOUD COVER OUTPUT.
PREVIOUS DISCUSSION BELOW...
550 AM UPDATE. RADICALLY ADJUSTED OVERNIGHT MINS AND HOURLIES
THIS MORNING UPWARD..AS CLOUDS AND WIND HAVE PREVENTED ANY FREE
FALL. STILL BELIEVE MOSTLY A VIRGA SCENARIO WITH ECHOES THIS
MORNING ACROSS THE NORTH...SO HAVE ONLY MORNING FLURRIES UP NORTH.
PREVIOUS DISCUSSION...
MODELS HAVE A DRY AND WEAK COLD FRONT STALLING AS IT SINKS INTO THE
NORTHERN PORTIONS OF OUR AREA TODAY...THEN LIFTING BACK AS A WARM
FRONT LATER TONIGHT. ARCTIC AIR HAS BECOME HISTORY...AND THE COLD
AIR BEHIND THIS NEW FRONT WILL STAY TO THE NORTH OF US AS THE WINDS
TURN FROM SOUTHWESTERLY TODAY TO LIGHT SOUTHEASTERLY TONIGHT. GIVEN
RECENT MODEL PERFORMANCE ON TEMP TRENDS DURING THIS MODIFICATION
PROCESS...WILL LEAN ON THE WARMER GUIDANCE TODAY...EXCEPT CUT A
COUPLE DEGREES OFF THAT IN THE NORTH WHERE MID TO HIGH CLOUDS IN
HIGH LEVEL MOISTURE WILL BE PREVAILING. THE ONE THING ABOUT THE
ARCTIC AIR THAT WILL BE VERY SLOW TO LOSE IS THE VERY LOW
DEWPOINTS...ESPECIALLY SINCE IT WILL CONTINUE DRY THRU TONIGHT.
THUS...WILL KEEP DEWPOINTS ON THE LOWER SIDE TODAY WHILE THE TEMPS
RECOVER. FOR TONIGHT...DESPITE THE LOWER DEWPOINTS...THE MODELS
APPEAR TOO LOW ON MIN TEMPS GIVEN THE EXPECTATION OF MID TO HIGH
CLOUDS AND A SOUTHEASTERLY PUFF. WILL LEAN AGAIN ON THE WARMER SIDE
OF GUIDANCE...AGAIN ESPECIALLY IN THE NORTH WITH MORE CLOUDS.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
WAS TEMPTED TO TAKE THE POPS OUT OF PERRY/MORGAN COUNTIES AT THE
BREAK POINT FROM THE NEAR TERM FORECAST AT 12Z SATURDAY...BUT THE
MODELS LEAVE TOO MUCH EVIDENCE OTHERWISE. LATEST 00Z RUN OF THE EURO
IS THE MOST AGGRESSIVE WITH THE NORTHWARD PUSH OF THE FRONTAL
SYSTEM. SHOULD BE FAIRLY DRY SATURDAY WITH THE COLD FRONT PASSING
SATURDAY NIGHT AND SUNDAY. WITH THE FLOW ALOFT SOUTHWESTERLY...WILL
EXPECT THE DEVELOPMENT OF A SURFACE LOW OVER THE DEEP SOUTH. THIS
BRINGS A RESURGENCE OF THE MOISTURE IN WHAT WILL BEGIN A PRIMARILY
WET PATTERN WITH FRONTAL SYSTEMS ORIGINATING IN THE SAME GENERAL
AREAS. GFS IS FURTHEST SOUTH AND EAST WITH THE MOISTURE THAT WOULD
LEAVE MUCH OF THE LOWLAND AREAS ON THE DRIER SIDE. WILL SET THIS
MODEL ASIDE FOR NOW...CAUTIOUSLY. SREF SIDES WITH THE GFS.
WILL BE CONCERNED WITH THE COLD AIR PUSH IN THE MOISTURE PUSH THAT
WILL TAKE PLACE SUNDAY NIGHT AND INTO MONDAY. IN TYPICAL
FASHION...THERE WILL BE A SHARP DIVIDING LINE IN THE RAIN SNOW
LINE...AND THE TRICK FOR THIS FORECAST OVER THE NEXT FEW DAYS WILL
BE TIMING HOW LONG IT TAKES TO GET THE COLD AIR TO TAKE HOLD AND IF
IT COINCIDES WITH THE MOISTURE. AS OF RIGHT NOW...NAM AND EURO ARE
GIVING SIGNIFICANT ACCUMULATIONS...ALTHOUGH THE SREF PROBABILITIES
FOR ACCUMULATING SNOW REMAINS LOW. THIS IS LEADING TO A LOWER
CONFIDENCE TO THE FORECAST FOR THE BEGINNING OF NEXT WORK WEEK THIS
MORNING. FROM A PERSONAL FORECASTING PREFERENCE STAND POINT...WOULD
LIKE TO SEE THAT SREF ON BOARD...ALTHOUGH DO HAVE SOME DAY 3 SNOW
ACCUMULATIONS IN THERE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE WILL BUILD IN FROM THE WEST ON MONDAY LOWERING THE
CHANCES FOR PRECIPITATION ON TUESDAY...HOWEVER A SLIGHT CHANCE OF
RAIN AND SNOW STILL EXIST FOR THE ENTIRE AREA...ESPECIALLY THE
MOUNTAINS. GFS HAS THE HIGH PRESSURE MOVING IN A BIT EARLIER THAN
THE ECMWF AND HPC SO THE TIMING OF THIS IS SUSPECT.
LOW PRESSURE OVER TEXAS AND STRENGTHENING OVER THE MS VALLEY WILL
BEGIN TO AFFECT WV ON TUESDAY. EXPECT THE LOW TO TRACK ALONG THE
OHIO RIVER AS DEPICTED BY THE ECMWF AND GFS...HOWEVER HPC IS SHOWING
THE LOW TRACKING OVER CENTRAL WV AND THE LOCATION OF THE LOW COULD
HAVE AN AFFECT ON WHETHER WE SEE MOSTLY SNOW OR MOSTLY RAIN.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS MOST SITES THROUGH AT LEAST
22Z. SATELLITE IMAGES SHOW A DECK ABOUT 5 KFT MOVING NORTHEAST
ACROSS THE WV AND KY BORDER. THIS CLOUD DECK WILL REACH CRW BY
19Z...BKW AROUND 21Z...AND CKB AND EKB ABOUT 22Z.
A COLD FRONT WILL STALL ACROSS IN AND OH THIS AFTERNOON. CLOUDS
ASSOCIATED WITH SUCH FRONT...AND A FLAT VORTICITY MAX RIDING ON
TOP OF IT NOTICEABLE AT H5 Y THE NAM WILL KEEP CLOUD DECK TO
THICKEN TOWARD THIS EVENING. THEREFORE...CODED LOWER CEILINGS AT
PKB FROM 5 KFT THROUGH 22Z...LOWERING TO 2.5 KFT BY MIDNIGHT.
THE FRONT IS EXPECTED TO LIFT NORTH TO PROVIDE VFR/MVFR CONDITIONS
UNDER SCATTERED CLOUD COVER.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: NONE.
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.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H M H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SATURDAY...
IFR STRATUS POSSIBLE IN SE OHIO SAT. IFR POSSIBLE IN RAIN SPREADING
SEWD THROUGH THE AREA SAT NT AND THEN CONTINUING SEWD...OUT OF THE
AREA...DURING SUN.
&&
.EQUIPMENT...
PKB ASOS HAS BEEN EXPERIENCING MALFUNCTIONS...RESULTING IN SOME
MISSING OR INCOMPLETE OBSERVATIONS. ELECTRONICS TECHNICIANS ARE
AWARE OF THE PROBLEM AND PARTS ARE BEING ACQUIRED. FOR
NOW...OBSERVATIONS HAVE BEEN AUGMENTED AT THE SITE.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...ARJ/JMV
SHORT TERM...26
LONG TERM...LS
AVIATION...ARJ
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1034 AM EST FRI JAN 31 2014
.SYNOPSIS...
FRONT STALLS IN OHIO VALLEY WITH LOW PRESSURE WAVE MOVING ALONG
IT SATURDAY. MUCH MILDER SATURDAY. COLD FRONT BRINGS MAINLY RAIN
SATURDAY NIGHT THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
SENT AN UPDATE TO INCREASE HIGHS TEMPERATURES FOR THIS AFTERNOON
AS A NON DIURNAL TREND WAS NOTICED OVERNIGHT AND IT WAS 40 DEGREES
ALREADY AT 1030 AM. USED SFC OBS AND LAV GUIDANCE FOR HIGHS TODAY.
POPULATED WIND FROM THE RAP HIGH RESOLUTION MODEL. ADJUSTED SKY
GRIDS STARTING WITH LATEST IR SATELLITE IMAGES EXTRAPOLATING WITH
NAM WINDS AND BLENDING WITH THE CMC MODEL CLOUD COVER OUTPUT.
PREVIOUS DISCUSSION BELOW...
550 AM UPDATE. RADICALLY ADJUSTED OVERNIGHT MINS AND HOURLIES
THIS MORNING UPWARD..AS CLOUDS AND WIND HAVE PREVENTED ANY FREE
FALL. STILL BELIEVE MOSTLY A VIRGA SCENARIO WITH ECHOES THIS
MORNING ACROSS THE NORTH...SO HAVE ONLY MORNING FLURRIES UP NORTH.
PREVIOUS DISCUSSION...
MODELS HAVE A DRY AND WEAK COLD FRONT STALLING AS IT SINKS INTO THE
NORTHERN PORTIONS OF OUR AREA TODAY...THEN LIFTING BACK AS A WARM
FRONT LATER TONIGHT. ARCTIC AIR HAS BECOME HISTORY...AND THE COLD
AIR BEHIND THIS NEW FRONT WILL STAY TO THE NORTH OF US AS THE WINDS
TURN FROM SOUTHWESTERLY TODAY TO LIGHT SOUTHEASTERLY TONIGHT. GIVEN
RECENT MODEL PERFORMANCE ON TEMP TRENDS DURING THIS MODIFICATION
PROCESS...WILL LEAN ON THE WARMER GUIDANCE TODAY...EXCEPT CUT A
COUPLE DEGREES OFF THAT IN THE NORTH WHERE MID TO HIGH CLOUDS IN
HIGH LEVEL MOISTURE WILL BE PREVAILING. THE ONE THING ABOUT THE
ARCTIC AIR THAT WILL BE VERY SLOW TO LOSE IS THE VERY LOW
DEWPOINTS...ESPECIALLY SINCE IT WILL CONTINUE DRY THRU TONIGHT.
THUS...WILL KEEP DEWPOINTS ON THE LOWER SIDE TODAY WHILE THE TEMPS
RECOVER. FOR TONIGHT...DESPITE THE LOWER DEWPOINTS...THE MODELS
APPEAR TOO LOW ON MIN TEMPS GIVEN THE EXPECTATION OF MID TO HIGH
CLOUDS AND A SOUTHEASTERLY PUFF. WILL LEAN AGAIN ON THE WARMER SIDE
OF GUIDANCE...AGAIN ESPECIALLY IN THE NORTH WITH MORE CLOUDS.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
WAS TEMPTED TO TAKE THE POPS OUT OF PERRY/MORGAN COUNTIES AT THE
BREAK POINT FROM THE NEAR TERM FORECAST AT 12Z SATURDAY...BUT THE
MODELS LEAVE TOO MUCH EVIDENCE OTHERWISE. LATEST 00Z RUN OF THE EURO
IS THE MOST AGGRESSIVE WITH THE NORTHWARD PUSH OF THE FRONTAL
SYSTEM. SHOULD BE FAIRLY DRY SATURDAY WITH THE COLD FRONT PASSING
SATURDAY NIGHT AND SUNDAY. WITH THE FLOW ALOFT SOUTHWESTERLY...WILL
EXPECT THE DEVELOPMENT OF A SURFACE LOW OVER THE DEEP SOUTH. THIS
BRINGS A RESURGENCE OF THE MOISTURE IN WHAT WILL BEGIN A PRIMARILY
WET PATTERN WITH FRONTAL SYSTEMS ORIGINATING IN THE SAME GENERAL
AREAS. GFS IS FURTHEST SOUTH AND EAST WITH THE MOISTURE THAT WOULD
LEAVE MUCH OF THE LOWLAND AREAS ON THE DRIER SIDE. WILL SET THIS
MODEL ASIDE FOR NOW...CAUTIOUSLY. SREF SIDES WITH THE GFS.
WILL BE CONCERNED WITH THE COLD AIR PUSH IN THE MOISTURE PUSH THAT
WILL TAKE PLACE SUNDAY NIGHT AND INTO MONDAY. IN TYPICAL
FASHION...THERE WILL BE A SHARP DIVIDING LINE IN THE RAIN SNOW
LINE...AND THE TRICK FOR THIS FORECAST OVER THE NEXT FEW DAYS WILL
BE TIMING HOW LONG IT TAKES TO GET THE COLD AIR TO TAKE HOLD AND IF
IT COINCIDES WITH THE MOISTURE. AS OF RIGHT NOW...NAM AND EURO ARE
GIVING SIGNIFICANT ACCUMULATIONS...ALTHOUGH THE SREF PROBABILITIES
FOR ACCUMULATING SNOW REMAINS LOW. THIS IS LEADING TO A LOWER
CONFIDENCE TO THE FORECAST FOR THE BEGINNING OF NEXT WORK WEEK THIS
MORNING. FROM A PERSONAL FORECASTING PREFERENCE STAND POINT...WOULD
LIKE TO SEE THAT SREF ON BOARD...ALTHOUGH DO HAVE SOME DAY 3 SNOW
ACCUMULATIONS IN THERE.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD IN FROM THE WEST ON MONDAY LOWERING THE
CHANCES FOR PRECIPITATION ON TUESDAY...HOWEVER A SLIGHT CHANCE OF
RAIN AND SNOW STILL EXIST FOR THE ENTIRE AREA...ESPECIALLY THE
MOUNTAINS. GFS HAS THE HIGH PRESSURE MOVING IN A BIT EARLIER THAN
THE ECMWF AND HPC SO THE TIMING OF THIS IS SUSPECT.
LOW PRESSURE OVER TEXAS AND STRENGTHENING OVER THE MS VALLEY WILL
BEGIN TO AFFECT WV ON TUESDAY. EXPECT THE LOW TO TRACK ALONG THE
OHIO RIVER AS DEPICTED BY THE ECMWF AND GFS...HOWEVER HPC IS SHOWING
THE LOW TRACKING OVER CENTRAL WV AND THE LOCATION OF THE LOW COULD
HAVE AN AFFECT ON WHETHER WE SEE MOSTLY SNOW OR MOSTLY RAIN.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
12Z FRIDAY THRU 12Z SATURDAY...
A MOSTLY DRY FRONTAL SYSTEM WILL STALL OVER OUR NORTHERN AREAS TODAY
BEFORE LIFTING BACK NORTH LATER TONIGHT. VFR WITH CEILINGS RANGING
FROM 7000-15000 FEET NORTH WITH A FEW MORNING FLURRIES...TO SCT-BKN
HIGH CLOUDS SOUTH.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: NONE.
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.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SATURDAY...
IFR STRATUS POSSIBLE IN SE OHIO SAT. IFR POSSIBLE IN RAIN SPREADING
SEWD THROUGH THE AREA SAT NT AND THEN CONTINUING SEWD...OUT OF THE
AREA...DURING SUN.
&&
.EQUIPMENT...
PKB ASOS HAS BEEN EXPERIENCING MALFUNCTIONS...RESULTING IN SOME
MISSING OR INCOMPLETE OBSERVATIONS. ELECTRONICS TECHNICIANS ARE
AWARE OF THE PROBLEM AND PARTS ARE BEING ACQUIRED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...ARJ/JMV
SHORT TERM...26
LONG TERM...LS
AVIATION...JMV
EQUIPMENT...ARJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1022 AM EST FRI JAN 31 2014
.SYNOPSIS...
TEMPERATURES WILL MODERATE OVER THE UPCOMING DAYS. ALONG WITH THE
MODERATION IN TEMPERATURES WILL COME SEVERAL CHANCES FOR
PRECIPITATION THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
TEMPS SNEAKING TO FZG NOW OVER THE HIGHER TERRAIN OF THE WEST BUT
CLOUDS ARE LOWERING A BIT TO THE WEST. WILL KEEP THE 20 POP FOR
THE LATE AFTN AND EVENING OVER THE WEST AND EVEN 30 POPS IN THE
FAR NW. BUT...AGAIN...ANY ACCUMS WILL BE REAL LIGHT. MOST OF THE
AREA WILL JUST BE MOSTLY CLOUDY.
PREV...
UPDATE AT 830 AM TO ADD IN MENTIONS OF SLEET AND SNOW IN THE FAR
SE...WHERE TAIL END OF LLVL JET STREAK...WARM ADVECTION AND SOME
UPPER JET DYNAMICS MUST BE TEAMING UP TO CREATE A BAND OF VERY
LIGHT MIXED PRECIP OVER YORK/LANC COS. SOME ACCUMS REPORTED. LOW
LAYERS OF ATMOS STILL DRY THOUGH...WITH ALL THIS FALLING FROM 5KFT
ALOFT. RECENT RUC SOUNDINGS SAY THAT IT COULD CONTINUE THROUGH
NOON. UNTIL WINDS BECOME DECIDEDLY WESTERLY. TO BORROW THE
EXPRESSION...INTERESTING OR IS IT CONFOUNDING.
PREV...
A COLD FRONT APPROACHING FROM THE GR LAKES WILL WEAKEN AS IT NEARS
THE FCST AREA. TODAY WILL BE RATHER CLOUDY OVER CENTRAL AND
NORTHERN SECTIONS...WITH PARTIAL SUNSHINE DEVELOPING OVER THE SERN
PART OF THE CWA. MUCH OF THE FORECAST AREA WILL REMAIN DRY WITH
JUST A SMALL CHANCE OF SOME LIGHT SNOW CREEPING INTO NWRN AREAS
LATER TODAY. IT WILL BE MILDER WITH TEMPERATURES MANAGING TO TOP
FREEZING OVER MOST OF THE REGION.
WHAT`S LEFT OF THE WEAK FRONT WILL LIFT BACK NORTH TONIGHT AS A
WARM FRONT. THE DEVELOPING WARM ADVECTION PATTERN WILL BRING
INCREASING CHANCES OF SOME LIGHT SNOW...MAINLY OVER THE NORTHERN
HALF OF THE AREA. AMOUNTS OF A FEW HUNDREDTHS ARE POSSIBLE.
&&
.SHORT TERM /SATURDAY/...
A DEEPENING LOW WILL SPEED DOWN THE ST LAWRENCE RIVER VALLEY
SATURDAY...WITH A SURGE OF PRECIP SLIDING UP MAINLY NORTH AND WEST
OF MY FCST AREA. THE BEST CHANCE OF PRE-COLD FRONTAL PRECIP WILL
ONCE AGAIN BE OVER MY NWRN ZONES WHERE A LIGHT RAIN-SNOW MIX WILL
CHANGE TO JUST RAIN AS TEMPS RISE TO NEAR 40 IN MOST AREAS.
DESPITE THE WARM FRONT LIFTING NORTH...MODEL PROGGED STABILITY AND
A STRONG NE LOW LEVEL AGEOSTROPHIC WIND INDICATE WE WILL STAY
COOL AIR DAMMED FOR MUCH OF THE DAY...SO DESPITE WHAT LOOKS LIKE A
POTENT SOUTHERLY GRADIENT...THE HIGHS MAY HOLD OFF UNTIL RATHER
LATE IN THE DAY TO OCCUR.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AN ACTIVE SPLIT FLOW JET STREAM PATTERN IS FORECAST TO DEVELOP AND
DOMINATE THE LOWER 48 TROUGH THE EXTENDED PERIOD. THE ARCTIC AIR
STAYS ENTRENCHED FROM THE UPPER MIDWEST INTO THE GR LAKES AND NERN
US...WITH PA SITTING RIGHT ON THE BATTLE ZONE BETWEEN THE SOUTHERN
MOISTURE AND NORTHERN CHILL.
THE COLD FRONT ASSOCIATED WITH OUR ST LAWRENCE RIVER VALLEY LOW
WILL PASS SUNDAY...AND BECOME STATIONARY JUST SOUTH OF THE AREA.
DIFFERENCES ARISE QUICKLY FROM THERE WITH THE ECMWF TAKING A LOW
THRU VA MONDAY...IMPLYING A GENERAL 3-6 INCH SNOWFALL FOR ABOUT
THE SERN 1/2 OR SO OF MY FCST AREA AS IT SPEEDS OFF THE MID ATL
COAST. THE GFS/GEFS KEEP THIS WAVE WEAKER AND MUCH FURTHER SOUTH.
THE NAM RUNS OUT OF PANELS WHEN THINGS GET INTERESTING...BUT EARLY
MONDAY IT SHOWS MORE OF A LOW THAN THE GFS/GEFS...BUT NOT AS FAR
NORTH AS THE ECMWF. SO I INTRODUCED THE CHANCE OF SOME LIGHT SNOW
MONDAY.
FROM THERE A MORE IMPORTANT CYCLONE IS MADE TO APPROACH FOR
WED...AND THERE IS BETTER AGREEMENT ON TIMING BETWEEN THE ECMWF
AND GFS/GEFS. THE ECMWF HAS ITS LOW TRACKING INTO WESTERN
PA...BEFORE REDEVELOPING QUICKLY OFF THE MID ATL COAST. THE
GFS/GEFS ARE BOTH FURTHER SOUTHEAST...WITH THE GEFS BEING THE MOST
EAST AND THUS THE COLDEST SET OF SOLUTIONS. AT THIS POINT A WINTRY
MIX IS INDICATED BETWEEN THE VARIOUS MODEL OUTCOMES AS WARM AIR
FLOODS IN ALOFT...BUT WITH SO MUCH SNOW COVER AND COLD AIR OVER
THE GR LAKES AND NE...WOULD NOT BE SURPRISED IF THE EVENTUAL STORM
TRACK WANDERS CLOSER TO THE COAST OVER THE NEXT SEVERAL MODEL
RUNS.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS AT TIMES TODAY AT BFD. -SN ALSO POSSIBLE LATER TODAY.
OTHERWISE...MAINLY VFR TODAY WITH MID LEVEL CLOUDS.
COLD FRONT WILL REACH INTO FAR NW PA THEN BOUNCE BACK N THIS
EVENING AS A WARM FRONT ON SATURDAY. THE MIDDLE OF THE NIGHT WILL
LIKELY BE DRY WITH LITTLE FORCING AND WINDS BACKING TO THE S AS
THE MINOR RIDGE SLIDES EAST. PERHAPS A SNOW SHOWER LATE TONIGHT
AT BFD.
MOST OF SAT WILL BE DRY...AS THE WARM FRONT CLEARS THE NRN BORDER.
BY AFTERNOON TEMPS WOULD BE WARM ENOUGH TO SUPPORT RAIN...BUT THE
BULK OF THE PRECIPITATION WOULD BE NORTH OF CENTRAL PA BY THEN.
SOME RAIN SHOWERS FOR LATE SATURDAY NIGHT INTO SUNDAY...AS THE
FRONT RETURNS AS A COLD FRONT DROPS SE.
SOME SNOW LOOKS LIKE A HIGH CHC ACROSS THE SE ON MONDAY...AS FAST
MOVING SYSTEMS LIFT NE FROM THE SW STATES INTO THE MID ATLANTIC
AREA. THUS...IFR RESTRICTIONS POSSIBLE IN MDT/LNS.
SOME RAIN POSSIBLE LATE TUE INTO WED...AS ANOTHER SYSTEM
LIFTS NE IN AN ACTIVE SW FLOW. PERHAPS SOME WET SNOW...BUT
AT THE CURRENT TIME...THE COLD AIR IS LIMITED.
OUTLOOK...
SUN...MVFR/IFR AM. CFROPA. NW FLOW/LOW CLOUDS POSS PM. BREEZY.
MON...MAINLY VFR. LIGHT SN AND MVFR/IFR POSS S. TUE...MAINLY
VFR...LOWERING CLOUDS AND PRECIP POSS LATE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...DANGELO/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
851 AM EST FRI JAN 31 2014
.SYNOPSIS...
TEMPERATURES WILL MODERATE OVER THE UPCOMING DAYS. ALONG WITH THE
MODERATION IN TEMPERATURES WILL COME SEVERAL CHANCES FOR
PRECIPITATION THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE AT 830 AM TO ADD IN MENTIONS OF SLEET AND SNOW IN THE FAR
SE...WHERE TAIL END OF LLVL JET STREAK...WARM ADVECTION AND SOME
UPPER JET DYNAMICS MUST BE TEAMING UP TO CREATE A BAND OF VERY
LIGHT MIXED PRECIP OVER YORK/LANC COS. SOME ACCUMS REPORTED. LOW
LAYERS OF ATMOS STILL DRY THOUGH...WITH ALL THIS FALLING FROM 5KFT
ALOFT. RECENT RUC SOUNDINGS SAY THAT IT COULD CONTINUE THROUGH
NOON. UNTIL WINDS BECOME DECIDEDLY WESTERLY. TO BORROW THE
EXPRESSION...INTERESTING OR IS IT CONFOUNDING.
PREV...
A COLD FRONT APPROACHING FROM THE GR LAKES WILL WEAKEN AS IT NEARS
THE FCST AREA. TODAY WILL BE RATHER CLOUDY OVER CENTRAL AND
NORTHERN SECTIONS...WITH PARTIAL SUNSHINE DEVELOPING OVER THE SERN
PART OF THE CWA. MUCH OF THE FORECAST AREA WILL REMAIN DRY WITH
JUST A SMALL CHANCE OF SOME LIGHT SNOW CREEPING INTO NWRN AREAS
LATER TODAY. IT WILL BE MILDER WITH TEMPERATURES MANAGING TO TOP
FREEZING OVER MOST OF THE REGION.
WHAT`S LEFT OF THE WEAK FRONT WILL LIFT BACK NORTH TONIGHT AS A
WARM FRONT. THE DEVELOPING WARM ADVECTION PATTERN WILL BRING
INCREASING CHANCES OF SOME LIGHT SNOW...MAINLY OVER THE NORTHERN
HALF OF THE AREA. AMOUNTS OF A FEW HUNDREDTHS ARE POSSIBLE.
&&
.SHORT TERM /SATURDAY/...
A DEEPENING LOW WILL SPEED DOWN THE ST LAWRENCE RIVER VALLEY
SATURDAY...WITH A SURGE OF PRECIP SLIDING UP MAINLY NORTH AND WEST
OF MY FCST AREA. THE BEST CHANCE OF PRE-COLD FRONTAL PRECIP WILL
ONCE AGAIN BE OVER MY NWRN ZONES WHERE A LIGHT RAIN-SNOW MIX WILL
CHANGE TO JUST RAIN AS TEMPS RISE TO NEAR 40 IN MOST AREAS.
DESPITE THE WARM FRONT LIFTING NORTH...MODEL PROGGED STABILITY AND
A STRONG NE LOW LEVEL AGEOSTROPHIC WIND INDICATE WE WILL STAY
COOL AIR DAMMED FOR MUCH OF THE DAY...SO DESPITE WHAT LOOKS LIKE A
POTENT SOUTHERLY GRADIENT...THE HIGHS MAY HOLD OFF UNTIL RATHER
LATE IN THE DAY TO OCCUR.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AN ACTIVE SPLIT FLOW JET STREAM PATTERN IS FORECAST TO DEVELOP AND
DOMINATE THE LOWER 48 TROUGH THE EXTENDED PERIOD. THE ARCTIC AIR
STAYS ENTRENCHED FROM THE UPPER MIDWEST INTO THE GR LAKES AND NERN
US...WITH PA SITTING RIGHT ON THE BATTLE ZONE BETWEEN THE SOUTHERN
MOISTURE AND NORTHERN CHILL.
THE COLD FRONT ASSOCIATED WITH OUR ST LAWRENCE RIVER VALLEY LOW
WILL PASS SUNDAY...AND BECOME STATIONARY JUST SOUTH OF THE AREA.
DIFFERENCES ARISE QUICKLY FROM THERE WITH THE ECMWF TAKING A LOW
THRU VA MONDAY...IMPLYING A GENERAL 3-6 INCH SNOWFALL FOR ABOUT
THE SERN 1/2 OR SO OF MY FCST AREA AS IT SPEEDS OFF THE MID ATL
COAST. THE GFS/GEFS KEEP THIS WAVE WEAKER AND MUCH FURTHER SOUTH.
THE NAM RUNS OUT OF PANELS WHEN THINGS GET INTERESTING...BUT EARLY
MONDAY IT SHOWS MORE OF A LOW THAN THE GFS/GEFS...BUT NOT AS FAR
NORTH AS THE ECMWF. SO I INTRODUCED THE CHANCE OF SOME LIGHT SNOW
MONDAY.
FROM THERE A MORE IMPORTANT CYCLONE IS MADE TO APPROACH FOR
WED...AND THERE IS BETTER AGREEMENT ON TIMING BETWEEN THE ECMWF
AND GFS/GEFS. THE ECMWF HAS ITS LOW TRACKING INTO WESTERN
PA...BEFORE REDEVELOPING QUICKLY OFF THE MID ATL COAST. THE
GFS/GEFS ARE BOTH FURTHER SOUTHEAST...WITH THE GEFS BEING THE MOST
EAST AND THUS THE COLDEST SET OF SOLUTIONS. AT THIS POINT A WINTRY
MIX IS INDICATED BETWEEN THE VARIOUS MODEL OUTCOMES AS WARM AIR
FLOODS IN ALOFT...BUT WITH SO MUCH SNOW COVER AND COLD AIR OVER
THE GR LAKES AND NE...WOULD NOT BE SURPRISED IF THE EVENTUAL STORM
TRACK WANDERS CLOSER TO THE COAST OVER THE NEXT SEVERAL MODEL
RUNS.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS AT TIMES TODAY AT BFD. -SN ALSO POSSIBLE LATER TODAY.
PERHAPS SOME LIGHT PRECIPITATION AT MDT AND LNS...BUT THE
AIRMASS IS QUITE DRY.
OTHERWISE...MAINLY VFR TODAY WITH MID LEVEL CLOUDS.
COLD FRONT MOVING SE TODAY WILL WORK BACK TO THE NORTH
ON SATURDAY...THUS MUCH OF THE DAY WILL BE ON THE DRY
SIDE. PERHAPS A SNOW SHOWER LATE TONIGHT AT BFD.
MOST OF SAT WILL BE DRY...AS THE WARM FRONT LIFTS
NE. AGAIN...PERHAPS A SNOW SHOWER ACROSS FAR NORTHERN PA
EARLY...THEN BY AFTERNOON TEMPS WOULD BE WARM ENOUGH
TO SUPPORT RAIN...BUT THE BULK OF THE PRECIPITATION
WOULD BE NORTH OF CENTRAL PA BY THEN.
SOME RAIN SHOWERS FOR LATE SATURDAY NIGHT INTO SUNDAY...AS
THE COLD FRONT DROPS SE.
SOME SNOW POSSIBLE ACROSS THE SE ON MONDAY...AS FAST MOVING
SYSTEMS LIFT NE FROM THE SW STATES INTO THE MID ATLANTIC AREA.
SOME RAIN POSSIBLE LATE TUE INTO WED...AS ANOTHER SYSTEM
LIFTS NE IN AN ACTIVE SW FLOW. PERHAPS SOME WET SNOW...BUT
AT THE CURRENT TIME...THE COLD AIR IS LIMITED.
OUTLOOK...
SAT...MAINLY VFR...BUT MVFR/IFR ACROSS THE NW...AND AGAIN
LATE.
SUN...MVFR/IFR AM. CFROPA. NW FLOW/LOW CLOUDS POSS PM.
BREEZY.
MON...MAINLY VFR. LIGHT SN AND MVFR/IFR POSS S.
TUE...MAINLY VFR...LOWERING CLOUDS AND PRECIP POSS LATE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1015 PM EST SAT FEB 1 2014
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AND SHIFT EAST THROUGH TONIGHT ALLOWING A
MOISTER AIRMASS INTO THE CAROLINAS AND NORTHEAST GEORGIA THROUGH THE
MIDDLE OF NEXT WEEK. AN ACTIVE WEEK IN WEATHER IS COMING WITH A
SERIES OF FRONTS CROSSING OUR REGION.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 945 PM...THE MAIN FCST CONCERN/CHALLENGE FOR THE EVENING
UPDATE IS THE TRENDS IN THE MVFR STRATUS...AND INCREASING SFC
DEWPTS...WHICH MAY AFFECT MIN TEMPS AND FOG DEVELOPMENT. HIGH PRES
CONTINUES TO DRIFT EAST OFF THE COAST...WHILE A COLD FRONT
APPROACHES FROM THE WEST. SWLY LLVL FLOW BETWEEN THE TWO SYSTEMS
CONTINUES TO ADVECT IN GULF MOISTURE ATOP A RESIDUAL DRY SFC-BASED
LAYER. THE 00Z FFC SNDG SHOWED A VERY SHALLOW SATURATED LAYER
BETWEEN 900-850 MB...WITH STRONG INVERSION FROM 850-800. MODELS SHOW
THE LLVL FLOW WILL VEER SLIGHTLY TO MORE WSWLY OVERNIGHT...PERHAPS
ENUF TO HAVE DOWNSLOPE AID SCATTERING OUT SOME OF THE FAIRLY THIN
STRATUS. IF THE STRATUS CLEARS IN LARGE ENUF AREAS...SOME LOCATIONS
MAY DEVELOP FOG...WHICH COULD BE DENSE. THIS IS ALREADY HAPPENING IN
SRN/CENTRAL GA. WITH THAT SAID...THE MAJORITY OF THE GUIDANCE KEEPS
ENUF MIXING AND LARGER DEWPT DEPRESSIONS SUCH THAT ANY CLEAR AREAS
WILL PROBABLY HAVE MORE LOW STRATUS FILL BACK IN RATHER THAN FOG.
THE RAP IS THE MOST BULLISH ON FOG ACRS THE GA AND SC
PIEDMONT...REACHING THE CHARLOTTE METRO AREA BY DAYBREAK. MY
THINKING IS TO LEAN TOWARD ONLY PATCHY FOG...PRIMARILY IN THE LWR
PIEDMONT SOUTH AND EAST OF I-85. HOWEVER...CONFIDENCE IS ON THE LOW
SIDE IN THIS ASPECT. THE OTHER CHANGE WITH THIS UPDATE WAS TO RAISE
MIN TEMPS UP A CATEGORY OR SO IN SPOTS...GIVEN THE LARGE INCREASE IN
DEWPTS...AND THE EXPECTED CLOUD COVER OVERNIGHT.
PREVIOUS DISCUSSION...
TONIGHT AND TOMORROW...MOISTURE PLUME ASSOCIATED WITH ISENTROPIC
ASCENT WILL PUSH OFF TO THE EAST OVERNIGHT LEADING TO DECREASING
POPS. LINGERING MOISTURE IN THE BOUNDARY LAYER WILL LIKELY ALLOW
FOR LOW CLOUDS TO PERSIST THROUGH THE OVERNIGHT HOURS BEFORE BURNING
OFF AROUND DAYBREAK SUNDAY. TEMPERATURES OVERNIGHT WILL ACTUALLY
REMAIN QUITE MILD AND ABOVE NORMAL AS DENSE SKY COVER INSULATES FROM
RADIATIONAL COOLING ACROSS MOST OF THE NC/SC PIEDMONT WITH COOLER
TEMPERATURES ACROSS THE MOUNTAIN VALLEYS. THE HIGHER ELEVATIONS
WILL LIKELY BE WARMER THAN VALLEY LOCATIONS DUE TO SOUTHWESTERLY
WARM ADVECTION ALOFT...THUS SOME PATCHY FOG IS POSSIBLE IN THE
VALLEY AREAS AS TEMPERATURES FALL OFF AND APPROACH SATURATION. WITH
THAT SAID...CONFIDENCE IS NOT SUBSTANTIALLY HIGH IN THAT REGARD AS
DEWPOINTS REMAIN VERY LOW. SUNDAY LOOKS TO BE A FAIRLY NICE DAY
ACROSS MOST THE REGION AS THE COLD FRONT APPROACHES FROM THE WEST.
POPS WILL RAMP BACK UP TO SOLID CHANCE LEVELS ACROSS THE WESTERN
MOUNTAIN ZONES AS THE FRONT APPROACHES. AS FOR THE
FOOTHILLS/PIEDMONT...EXPECT ABOVE NORMAL TEMPERATURES AMIDST PARTLY
TO MOSTLY CLOUDY SKIES WITH LIGHT/MODERATE SOUTHWEST WINDS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 155 PM SATURDAY...WITH THE UPPER AIR PATTERN CHANGE WILL COME
A TRANSITION TO A WET/UNSETTLED REGIME ACROSS THE SOUTHEAST AND
MID-ATLANTIC DURING THE UPCOMING WEEK. SOUTHERN STREAM SHORT WAVE
TROUGH EJECTING FROM THE SOUTHERN PLAINS LATE MONDAY WILL INITIATE
LOW-LEVEL CYCLOGENESIS ACROSS THE TENN VALLEY BY EARLY MONDAY...
WITH SURFACE LOW LIFTING NORTHEAST ACROSS THE LEE OF THE
APPALACHIANS. THIS WILL ACT TO MAXIMIZE LOW-LEVEL ISENTROPIC LIFT
AND FRONTOGENESIS ACROSS WESTERN NC AND EAST TENN BY LATE SUNDAY
NIGHT. PRECIP SHIELD WILL MOVE GENERALLY ALONG AND NORTH OF THE
SURFACE LOW...WHERE QPF OF 1 TO 2 INCHES CAN BE EXPECTED...MAINLY
ALONG AND WEST OF THE BLUE RIDGE. MAX AMOUNTS WILL LIKELY OCCUR
ACROSS SOUTHWEST NC...WHERE STRONG SW FLOW WILL RESULT IN UPSLOPE
LIFT...AUGMENTING THE SYNOPTIC FORCING. ELSEWHERE...QPF SHOULD
GENERALLY RANGE FROM .5-1 INCH ACROSS THE FOOTHILLS TO .25-.5 INCH
ACROSS SOUTHERN PIEDMONT AREAS. WINTRY PRECIP CONTINUES TO APPEAR
LIKE A VERY LOW PROBABILITY EVENT...EVEN ACROSS THE NORTHERN NC
MTNS...WHERE OPERATIONAL MODEL SOUNDINGS ARE ALL SOLIDLY IN THE RAIN
SPECTRUM. EVEN ENSEMBLE GUIDANCE IS STRONGLY SUPPORTIVE OF AN
ALL-RAIN EVENT ACROSS THE NRN MTNS.
FORCING WILL SHIFT RAPIDLY NE OF THE AREA BY MONDAY AFTERNOON...
BRINGING AN END TO WIDESPREAD RAIN. HOWEVER...AS SURFACE LOW SHIFTS
OFF THE MID-ATLANTIC COAST...1030+ MB SURFACE HIGH WILL BE OOZING
ACROSS THE OHIO VALLEY/LOWER GREAT LAKES...SPILLING COLD AIR DOWN
THE EASTERN SEABOARD AND SIGNALING THE ONSET OF A PERIOD OF
CLASSICAL COLD AIR DAMMING ACROSS THE SOUTHEAST/MID-ATLANTIC BY LATE
MONDAY NIGHT. AS ANOTHER...STRONGER SHORT WAVE BEGINS TO LIFT OUT OF
THE SOUTHERN PLAINS BY TUE MORNING...UPGLIDE WILL INCREASE ABOVE
COLD AIR WEDGE ACROSS OUR AREA...RESULTING IN LIGHT PRECIP
DEVELOPMENT. A CONSENSUS OF FORECAST SOUNDINGS FROM THE NAM...
SREF...AND GFS SUGGESTS A RATHER HIGH POTENTIAL OF -FZRA IN THE
CLIMATOLOGICALLY FAVORED AREAS OF THE EASTERN BLUE RIDGE (NORTH OF
I-40) WITHIN CLASSIC CAD REGIME EARLY TUE...AND WE WILL CONTINUE A
MENTION OF SEVERAL HOURS OF -FZRA OR -RA/-FZRA. FORTUNATELY...
GUIDANCE ALSO SEEMS TO HAVE ARRIVED AT A CONSENSUS THAT THE PARENT
HIGH WILL BE TRANSIENT...AND THAT CAD MAY BE IN A WEAKENING PHASE BY
TUE AFTERNOON...WHEN PRECIP RATES WOULD BEGIN TO INCREASE.
THEREFORE...WHILE A BRIEF PERIOD OF LIGHT ICE ACCUMULATION APPEARS
LIKELY...ICE STORM CONDITIONS CONTINUE TO LOOK UNLIKELY ATTM.
AS SURFACE LOW LIFTS RAPIDLY NORTHEAST ON THE WEST SIDE OF THE
APPALACHIANS...CAD EROSION SHOULD GRADUALLY OCCUR TUE NIGHT INTO
EARLY WED... RESULTING IN DIMINISHING UPGLIDE PRECIP AHEAD OF
ADVANCING COLD FRONTAL BAND. WITH WEAKENING FORCING ALONG THE
FRONTAL ZONE...MODEL GUIDANCE DEPICTS A DIMINISHING BAND OF PRECIP
ALONG THE FRONT AS IT TRAVERSES THE AREA EARLY WED. HOWEVER...IT IS
LIKELY THAT SOME DESTABILIZATION WILL OCCUR IN THE WARM SECTOR BY
WED AFTERNOON...WITH THE PRECIP BAND LIKELY BECOMING REINVIGORATED
AS IT INTERACTS WITH THIS UNSTABLE AIR. IF THE COLD FRONT PROVES TO
MOVE MORE SLOWLY THAN CURRENT GUIDANCE SUGGESTS...THUNDERSTORMS WILL
BE POSSIBLE ACROSS THE PIEDMONT WED AFTERNOON... BUT CONFIDENCE IS
STILL TOO LOW TO FORECAST TS OCCURRENCE ATTM.
TEMPS WILL GENERALLY BE MUCH ABOVE NORMAL THROUGH THE PERIOD...WITH
THE WARM TREND INTERRUPTED BY VERY COOL CONDITIONS (TEMPS AT LEAST
10 DEGREES BELOW CLIMO) WITHIN THE CAD REGIME LATE MON NIGHT THROUGH
TUE EVENING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
AS OF 225 PM EST SAT...GOOD MODEL AGREEMENT IS HAD IN THE FIRST
PORTION OF THE FCST. THE NW FLOW SN SHOULD BE TAPERING OFF RATHER
QUICKLY WED NIGHT AS DRYING OCCURS IN THE H92/H85 LAYER ON THE FRONT
END OF A DRY AND COLD ARCTIC AIRMASS. THERE SHOULDN/T BE TOO MUCH OF
A SE/RN PUSH WITH THE ARCTIC FRONT OUTSIDE THE MTNS THU AS THE MEAN
MLVL FLOW REMAINS SW/LY. THIS SHOULD CREATE A DISPARATE MAX
TEMPERATURE REGIME ACROSS THE FA WITH THE MTN VALLEYS WARMING ABOUT
5-8 DEGREES LESS THAN THE NON/MTNS. OVERALL...MAX TEMPS SHOULD BE
HELD ABOUT 8-12 DEGREES BELOW NORMAL IN GOOD INSOLATION YET COLD
N/LY SFC FLOW.
UNCERTAINTY INCREASES IN THE FCST BEGINNING THU EVENING THROUGH THE
PERIOD. THE 00Z GFS IS STILL A COLDER AND MORE DYNAMIC OUTLIER THAN
THE CWM/ECMWF SOLNS AND THE MODEL HAS A VERY DIFFERENT ULVL
CONFLUENT PATTERN OVER THE NE CONUS. THE GFS IS PRODUCING A MUCH
STRONGER AND COLDER SFC HIGH THAN THE OTHER OP MODELS AS IT/S
UPPER PATTERN INCLUDES AN UPSTREAM RIDGE BEHIND THE CONFLUENT ZONE.
THE OTHER MODELS HAVE CYCLONIC FLOW IN THIS AREA...THUS THE GFS IS
ABLE TO SUSTAIN STRONGER LLVL SUPPORT.
A QUICK LOOK AT THE INCOMING 12Z ECMWF SHOWS THIS MODEL IS TRENDING
TOWARD THE UPPER PATTERN OF THE GFS...BUT IT STILL HAS A WEAKER SFC
LOW...ALBEIT IN A BETTER CAD POSITION BY 12Z FRI. SOUNDINGS ON THE
GFS ARE SO COLD WITH THE CAD ONSET THAT THEY SHOW ALL SNOW FOR THE
FIRST PART OF FRI CHANGING OVER THE -FZRA IN THE AFTERNOON ACROSS
THE NRN ZONES. THE OLD ECMWF HAD ALL RAIN...WHILE THE NEW ECMWF
SOUNDINGS ARE MUCH COLDER THROUGH H7. WITH SO MUCH CHANGE OCCURRING
IN THE MODELS AND VARYING AVAILABLE MOISTURE DIFFERENCES ASSOCIATED
WITH SFC CYCLOGENESIS...POPS HAVE BEEN LEFT IN THE CHANCE RANGE
WITH A PUSH TOWARD THE HIGHER END. WILL STILL COUNT ON A STRONG WARM
NOSE BUILDING IN FRI AND MAKING THE CASE FOR -FZRA AS THE STRONGER
CAD SCENARIO LOOKS TO BE FAVORED ATTM. IT/S TOO EARLY TO SPECULATE ON
QPF/ICE AMOUNTS AS THE LLVL MASS FIELDS/FLUXES HAVE LOW CONFIDENCE
AND NEED TO BE FIGURED OUT...BUT THIS WILL BE A SYSTEM TO KEEP AN
EYE ON FRI INTO SAT.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AT KCLT...CIGS ARE EXPECTED TO BOTTOM OUT IN THE 1500-2000 FT RANGE
THIS EVENING...AS BEST ISENT LIFT SHIFTS TO THE EAST. LLVL FLOW WILL
VEER TO WSW OVERNIGHT...WHICH MAY NOT ACHIEVE ENUF OF A DOWNSLOPE
COMPONENT TO SCATTER OUT THE STRATUS. FCST SNDGS SHOW A STRONG
INVERSION ATOP THE CLOUD LAYER. SO MVFR CIGS WILL LIKELY PERSIST
THRU THE NIGHT AND SUNDAY MRNG. WITH THAT SAID...MUCH OF THE
GUIDANCE WANTS TO SCATTER THINGS OUT OVERNIGHT...SO THAT IS A
POSSIBILITY. HOWEVER...IF THAT HAPPENS...LIFR STRATUS MAY DEVELOP
(HINTED IN THE BUFKIT SOUNDINGS). SO I WILL PUT A SCT004 CLOUDS
DURING THE PERIOD NEAR DAWN. WSWLY FLOW SHUD HELP CLOUDS SCATTER OUT
WITH HELP FROM DAYTIME HEATING SUNDAY AFTN. OTHERWISE...THE BL STILL
LOOKS TOO DRY FOR ANY PRECIP OR FOG TO CAUSE RESTRICTIONS. WINDS
WILL BE LIGHT...FAVORING A SW DIRECTION THRU THE PERIOD...INCREASING
TO 5 TO 10 KTS SUNDAY AFTN.
ELSEWHERE...ALL SITES STARTING OUT MVFR (EXCEPT KAVL) AT TIME OF TAF
ISSUANCE. CIGS HAVE BEEN STEADILY LOWERING THE LAST FEW HOURS...BUT
ARE EXPECTED TO BOTTOM OUT THIS EVENING...GENERALLY IN THE LOW MVFR
RANGE. GUIDANCE GENERALLY WANTS TO SCATTER OUT THE STRATUS
OVERNIGHT...AS WINDS VEER TO WSWLY. HOWEVER...UNLESS DOWNSLOPE
COMPONENT IS STRONG ENUF...THE CLOUDS MAY NOT SCATTER...AS FCST
SNDGS SHOW STRONG INVERSION ATOP THE CLOUD DECK. SO I GENERALLY KEPT
THE CLOUDS IN OVERNIGHT PER 18Z TAFS. WITH THAT SAID...IF CLOUDS
SCATTER OUT...FCST SNDGS HINT THAT LIFR STRATUS MAY DEVELOP IN
SPOTS. CLOUDS SHUD BE ABLE TO SCATTER OUT BETTER ONCE DAYTIME
HEATING AND DOWNSLOPE IMPROVE AROUND MIDDAY SUNDAY. WINDS WILL BE
LIGHT/VRB OVERNIGHT...THEN FAVORING A SW DIRECTION FROM EARLY
MORNING THRU THE AFTN (5-10KTS).
OUTLOOK...A COLD FRONT WILL ENTER THE AREA SUNDAY NIGHT...PRODUCING
SHOWERS AND RESTRICTIONS...WHICH WILL CONTINUE INTO MONDAY.
CONFIDENCE TABLE...
03-09Z 09-15Z 15-21Z 21-03Z
KCLT HIGH 80% HIGH 92% HIGH 94% HIGH 100%
KGSP HIGH 95% HIGH 97% HIGH 90% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 87%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU MED 78% HIGH 95% HIGH 80% HIGH 100%
KAND MED 77% HIGH 81% HIGH 84% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...ARK/CDG
SHORT TERM...JDL
LONG TERM...SBK
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
955 PM CST SAT FEB 1 2014
.DISCUSSION...MADE SOME ADJUSTMENTS TO FORECAST FOR FRONTAL TIMING
AND AFFECTS. TIMING IS STILL LOOKING PRETTY GOOD...BUT MAYBE AN
HOUR OR SO FASTER. BIGGER CHANGE WAS WITH COOLING TEMPERATURES
AND LOWERING DPTS FASTER. RUC HAS A GOOD HANDLE ON TIMING...BUT
MAY BE DECREASING TEMPS TOO QUICKLY...WITH MOST OF THE AREA IN THE
MID 40S BY EARLY AFTERNOON. HAVE BROUGHT TEMPS INTO THE 50S FOR
EVERYONE LATE MORNING/EARLY AFTERNOON...AND SOME UPPER 40S NORTH.
&&
.PREV DISCUSSION... /ISSUED 544 PM CST SAT FEB 1 2014/
DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 00Z TAFS.
AVIATION...SKIES HAVE CLRD OUT ACROSS MUCH OF S TX EXCEPT FOR
AROUND VCT AREA THIS AFTERNOON. CLOUDS ARE EXPECTED TO SPREAD
ACROSS S TX OVERNIGHT ALONG WITH DVLPG FOG. A MIX OF STRATUS AND
FOG WILL LEAD TO MVFR CIGS/VSBYS THIS EVENING AND IFR/LIFR
OVRNIGHT...ESPECIALLY EAST OF A HEBBRONVILLE TO TILDEN LINE. A
COLD FRONT IS EXPECTED TO MOVE THROUGH S TX SUNDAY MORNING WITH A
WSHFT INITIALLY ACROSS THE VCT AREA BETWEEN 13-15Z AND
LRD...ALI...CRP BTWN 15-17Z. WINDS WILL STRENGTHEN FROM THE N
THROUGH SUNDAY AFTERNOON. THERE IS A CHANCE OF -SHRA`S ALONG AND
BEHIND THE COLD FRONT WHICH IS EXPECTED TO KEEP CIGS AT MVFR
LEVELS THROUGHOUT THE DAY.
PREV DISCUSSION... /ISSUED 432 PM CST SAT FEB 1 2014/
SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...SOUTHERLY FLOW
TONIGHT WILL CONTINUE TO FUNNEL MOISTURE INTO THE LOWER LVLS AHEAD
OF AN APPROACHING COLD FRONT. SHORTWAVE TROUGH WILL SWEEP ACROSS
THE STATE AND BRING DOWN AN ASSOCIATED COLD FRONT SUNDAY MORNING.
MODELS IN FAIR AGREEMENT WITH TIMING OF FROPA...WITH IT ENTERING
THE THE NORTHERN BORDERS OF THE CWA RIGHT AROUND 12Z AND IT
PUSHING OFFSHORE IN THE EARLY AFTERNOON. TEMPERATURES WILL BE A
LITTLE TRICKY WITH HIGHS EXPECTED TO BE REACHED IN THE MORNING...AND
FALLING TEMPERATURES ACROSS THE REGION IN THE AFTERNOON TOMORROW.
SUFFICIENT UPPER LVL SUPPORT WITH THIS FRONT AND PLENTIFUL
MOISTURE SHOULD PROVIDE A SLIGHT CHANCE TO CHANCE FOR SHOWERS TO DEVELOP
ACROSS THE REGION...BEGINNING TONIGHT AND INCREASING TOMORROW.
KEPT POPS HIGHEST OVER THE NORTHEAST ZONES WHERE BETTER MOISTURE
AND DYNAMICS WILL BE FOR DEVELOPMENT. FOG WILL BE ANOTHER ISSUE
TO CONTEND WITH TONIGHT INTO TOMORROW MORNING AHEAD OF THE FROPA.
EXPECT WINDS OVERLAND TO DIMINISH MORE TONIGHT...AND AREAS OF FOG
MAY DEVELOP ACROSS COASTAL BEND...PLAINS...AND VICTORIA
CROSSROADS. FOG OVER THE BAYS AND NEARSHORE WATERS WILL BE MORE
DENSE TONIGHT THAN THE PREVIOUS NIGHT AS WELL...WITH LOWER
WINDS...AND HIGHER DEWPOINTS OVER THE COOL WATERS.
LONG TERM (MONDAY THROUGH SATURDAY)...LONG TERM FORECAST A BIT OF
A ROLLER COASTER ON TEMPS AND WX. FORECAST BEGINS WITH COOL
AIRMASS STILL IN PLACE MONDAY UNDER MOSTLY CLOUDY TO OVERCAST
SKIES. HIGHS ONLY IN THE LOW 50S ON MONDAY WITH NORTH WIND
WEAKENING AND VEERING NORTHEAST AS HIGH PRESSURE MOVES EAST.
SOUTHERLY LOW LEVEL FLOW AND WAA/ISENTROPIC UPGLIDE INCREASE
MONDAY NIGHT IN RESPONSE TO ROBUST SHORTWAVE AND DIGGING TROUGH
COMING OUT OF THE DESERT SOUTHWEST INTO WEST TEXAS. ISOLATED TO
SCATTERED SHOWERS LOOK TO DEVELOP ACROSS SOUTH TEXAS LATE MONDAY
NIGHT THROUGH TUESDAY MORNING. THE SHORTWAVE LIFTS NORTHEAST INTO
NORTH TEXAS DURING THE DAY ON TUESDAY...AND DRAGS BOUNDARY THROUGH
THE AREA WITH DRYING/CLEARING OCCURRING WEST TO EAST. THIS RESULTS
IN MUCH WARMER TEMPERATURES HERE TUESDAY AFTERNOON COMPARED TO
MONDAY...WITH HIGHS TUESDAY INTO THE LOW TO MID 70S AWAY FROM THE
IMMEDIATE COAST. AS THE SHORTWAVE DEPARTS TO THE NORTHEAST A
STRONGER RE-ENFORCING COLD FRONT MOVES THROUGH SOUTH TEXAS
WEDNESDAY MORNING. INITIALLY DRY ALONG AND BEHIND THE FRONT
WEDNESDAY...BUT COOLER WITH HIGHS BACK INTO THE 50S TO AROUND 60.
THEN THURSDAY INTO FRIDAY ANOTHER TROUGH DIGS OVER THE WESTERN
U.S. INTO THE DESERT SOUTHWEST. COASTAL TROUGHING DEVELOPS KEEPING
THE COLD AIR IN PLACE ACROSS SOUTH TEXAS...AND ISENTROPIC UPGLIDE
DEVELOPS IN RESPONSE TO THE APPROACHING SHORTWAVE...PRODUCING
CLOUDS AND CHANCES FOR LIGHT RAIN ACROSS THE REGION. TEMPERATURES
MAY NOT MAKE IT OUT OF THE LOW TO MID 40S THURSDAY AND UPPER 40S
FRIDAY FOR MANY AREAS. THAT UPPER LEVEL TROUGH LOOKS TO MOVE
ACROSS THE SOUTHERN PLAINS ON SATURDAY...PUSHING ANOTHER COLD
FRONT THROUGH THE AREA BUT RESULTING IN CLEARING SKIES AND
ACTUALLY WARMER TEMPERATURES SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 64 67 39 52 49 / 10 30 10 10 40
VICTORIA 58 59 35 53 48 / 20 50 10 10 50
LAREDO 63 66 39 57 48 / 10 20 10 10 20
ALICE 62 67 38 53 47 / 10 30 10 10 40
ROCKPORT 63 67 39 50 50 / 20 40 10 10 50
COTULLA 56 58 35 55 45 / 10 30 10 10 30
KINGSVILLE 64 68 39 53 48 / 10 30 10 10 40
NAVY CORPUS 64 67 37 52 51 / 10 30 10 10 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM 3 PM SUNDAY TO 6 AM CST MONDAY FOR THE
FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT
ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT
O`CONNOR...COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS
OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT
ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM.
DENSE FOG ADVISORY UNTIL 9 AM CST SUNDAY FOR THE FOLLOWING
ZONES: BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT
O`CONNOR...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL OUT 20 NM.
&&
$$
PZ/83...SHORT TERM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
942 PM CST SAT FEB 1 2014
.DISCUSSION...
NO MAJOR CHANGES WITH THE OVERALL FCST AS THE COLD FRONT REMAINS
ROUGHLY ON TIME FOR FROPA OVER THE NORTHERN ZONES JUST AFTER MID-
NIGHT...THEN PROGRESSING TO THE COASTLINE BY NOON SUN. MEANWHILE
AHEAD OF THIS BOUNDARY...LOW CLOUDS/PATCHY FOG WILL BE THE ISSUE
(WITH THE MORE DENSE AREAS OF SEA FOG PREVAILING RIGHT ALONG THE
COAST/BEACHES). WINDS JUST ABOVE THE SFC APPEAR TO BE STAYING ON
THE HIGH SIDE (AS PER HGX VAD) SO NOT EXPECTING WIDESPREAD DENSE
FOG/REALLY LOW VISIBILITIES FOR THE INLAND AREAS THROUGH SUNRISE
ATTM. 41
&&
.PREV DISCUSSION... /ISSUED 754 PM CST SAT FEB 1 2014/
AVIATION...VERY MOIST LL IN PLACE OVER THE AREA WITH ESE TO SE
FLOW. A FEW SPRINKLES DOTTING THE AREA BUT BECOME MORE SCATTERED
NEAR THE COLD FRONT. AT 01Z THE FRONT WAS CREEPING SOUTH AT ABOUT
7-8 KNOTS AND SHOULD REACH CLL AROUND 07-09Z. CIGS ACROSS THE
REGION SHOULD CONTINUE TO FALL AND EXPECT WIDESPREAD IFR CIGS AND
LIKELY DROPPING INTO LIFR 300-500 FT. WITH THE ARRIVAL OF THE
FRONT THE CIGS MAY RISE SLIGHTLY BUT LIGHT RAIN SHOULD BECOME MORE
COMMON AND WILL KEEP THE LL MOIST. SEA FOG WAS APPARENT THIS
AFTERNOON AND HAS MOVED ACROSS THE ISLAND WITH GLS VISBY DOWN TO
2-5 MILES. EXPECT THAT VISBY 2-5 MILE VISBY WILL SPREAD INLAND AS
TEMPERATURES VERY SLOW LOWER FROM THE UPPER 60S TO THE LOWER TO
MID 60S. RR OF UPPER JET TRAVERSES THE AREA SUNDAY AND EXPECT THAT
LIGHT RAIN SHOULD BE FAIRLY WIDESPREAD. DRYING SETS IN WITH 850
FROPA 00Z IN THE CLL/UTS AREAS AND SHOULD BE THE END OF THE
PRECIP. STRONG INVERSION SHOULD REMAIN AND TRAPPED LL MOISTURE
WILL KEEP CIGS OF 1000-1500 IN PLACE THROUGH AT LEAST EARLY MONDAY
MORNING. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 46 48 35 51 44 / 40 50 10 10 60
HOUSTON (IAH) 63 63 39 52 46 / 40 70 20 10 40
GALVESTON (GLS) 57 61 42 50 50 / 30 70 40 10 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
754 PM CST SAT FEB 1 2014
.AVIATION...
VERY MOIST LL IN PLACE OVER THE AREA WITH ESE TO SE FLOW. A FEW
SPRINKLES DOTTING THE AREA BUT BECOME MORE SCATTERED NEAR THE COLD
FRONT. AT 01Z THE FRONT WAS CREEPING SOUTH AT ABOUT 7-8 KNOTS AND
SHOULD REACH CLL AROUND 07-09Z. CIGS ACROSS THE REGION SHOULD
CONTINUE TO FALL AND EXPECT WIDESPREAD IFR CIGS AND LIKELY
DROPPING INTO LIFR 300-500 FT. WITH THE ARRIVAL OF THE FRONT THE
CIGS MAY RISE SLIGHTLY BUT LIGHT RAIN SHOULD BECOME MORE COMMON
AND WILL KEEP THE LL MOIST. SEA FOG WAS APPARENT THIS AFTERNOON
AND HAS MOVED ACROSS THE ISLAND WITH GLS VISBY DOWN TO 2-5 MILES.
EXPECT THAT VISBY 2-5 MILE VISBY WILL SPREAD INLAND AS
TEMPERATURES VERY SLOW LOWER FROM THE UPPER 60S TO THE LOWER TO
MID 60S. RR OF UPPER JET TRAVERSES THE AREA SUNDAY AND EXPECT THAT
LIGHT RAIN SHOULD BE FAIRLY WIDESPREAD. DRYING SETS IN WITH 850
FROPA 00Z IN THE CLL/UTS AREAS AND SHOULD BE THE END OF THE
PRECIP. STRONG INVERSION SHOULD REMAIN AND TRAPPED LL MOISTURE
WILL KEEP CIGS OF 1000-1500 IN PLACE THROUGH AT LEAST EARLY MONDAY
MORNING.
45
&&
.PREV DISCUSSION... /ISSUED 356 PM CST SAT FEB 1 2014/
DISCUSSION...
ANOTHER WARM AND OVERCAST DAY WITH WHAT APPEARS TO BE THE EARLY
SIGNS OF SEA FOG BEGINNING TO AFFECT THE IMMEDIATE GALVESTON COASTLINE
AT THE TOP OF THE HOUR. WOULDN`T BE SURPRISED IF DENSE SEA FOG
BECOMES THE MAIN TOPIC OF THE EVENING GOING INTO EARLY SUNDAY JUST
AHEAD OF AN APPROACHING FRONTAL BOUNDARY. VERY SLOW-MOVING COLD
FRONTAL BOUNDARY SEEMINGLY HUNG UP OVER CENTRAL TEXAS TODAY WILL
SLIP DOWN INTO OUR FAR NORTHERN COUNTIES AT (OR SHORTLY AFTER)
MIDNIGHT. THE PRE-FRONTAL TROUGH MAY REACH THE CITY AROUND
SUNRISE...VARYING WINDS...BUT THE MAIN FRONT WILL COME THROUGH
AROUND NOON AND REACH THE COAST ABOUT THIS TIME TOMORROW. THERE IS
A MODEST CHANCE THAT A SHORT FUSE COASTAL WIND ADVISORY MAY BE
REQUIRED TOMORROW EVENING TO ACCOUNT FOR A FEW HOURS OF 25 MPH
NORTH WINDS. AS LOWER LEVEL WINDS BACK AROUND NORTH THROUGH THE
DAY...RAIN CHANCES WILL INCREASE FROM CHANCE TO LIKELY. THE BEST
ISENTROPIC LIFT...IN TANDEM WITH THE LIFTING NORTH CENTRAL TEXAS
SHORTWAVE TROF...WILL HAVE THE HIGHEST RAIN CHANCES OCCURRING
DURING THE DAYLIGHT HOURS AND FOCUSED MORE ACROSS THE NORTH (CENTRAL)
AND NORTHEASTERN CWA. RAIN QUICKLY EXITS EAST AS THE BACKING COLD
AND DRY AIR MASS WHISKS IN LATE SUNDAY INTO EARLY MONDAY. OVERCAST
CONDITIONS WILL STILL EXIST THROUGH MONDAY AS MOISTURE MAY GET
TRAPPED WITHIN A 900MB-SFC LOW LEVEL INVERSION LAYER. THIS FACT...
COMBINED WITH MILD COLD AIR ADVECTION (AROUND 10 DEG C AT 85H)...
WILL MAKE FOR `COOL-ISH` MONDAY MORNING IN THE MID 30S NORTH TO
LOW 40S AT COAST...SLUGGISH WARMING INTO THE AVERAGE UPPER 40S TO
LOWER 50S THAT AFTERNOON WITH A WEAKENING NORTH-NORTHEAST WIND.
THE NEXT SHOT OF RAIN COMES TUESDAY AS A RELATIVELY DEEPER TROUGH
AND ACCOMPANYING SHORTWAVE MOVES INTO THE TEXAS PANHANDLE THAT
MORNING. ALL OF THE ELEMENTS OF THE WARM SECTOR COME INTO PLAY
TUESDAY THAT WILL HAVE HIGH CHANCE TO LIKELY POPS IN PLACE...WITH
THE MAIN RAIN INHIBITER BEING THAT OF A 925MB WARM NOSE. A STRONGER
SOUTH-SOUTHWESTERN CWA CAP WILL POSITION HIGHER POPS OVER THE NORTH-
NORTHEAST FORECAST AREA THAT MORNING INTO AFTERNOON. 12Z PROFILES
ALL INDICATE JUST RAIN...WARMING FROM SURFACE UP TO 900MB...ISOTHERMAL
UP THROUGH ABOUT 700 MB. BEST UPPER LEVEL FORCING OCCURS LATTER
TUESDAY AS YET ANOTHER PROGRESSIVELY-MOVING COLD FRONT TRAVELS
ACROSS THE NORTHERN GULF COAST WEDNESDAY MORNING. THIS BACKING AIR
MASS IS FORECAST TO BE COLDER THAN TOMORROW`S...MID-LEVELS COOLING
INTO THE SINGLE DIGITS THROUGH WEDNESDAY. MUCH COLDER WEATHER TO
CLOSE OUT THE WEEK AS DAYS STRUGGLE TO WARM INTO THE LOW TO MID
40S UP NORTH UNDER OVERCAST...NORTHERLY WINDS...AND PERIODS OF
PRECIPITATION. A THIRD WESTERN TROUGH WILL MOVE INTO THE DESERT
SW/GREAT BASIN EARLY FRIDAY AND POSSIBLY PLACE THE LONE STAR IN
THE PATH OF GREATER PACIFIC MOISTURE...A NORTHEAST TRAVELING
S/W...AND THE DEVELOPMENT OF AN INVERTED TROUGH OVER THE WESTERN
GULF. ENSEMBLE ARE A BIT OFF ON THE EVOLUTION OF THESE FEATURES
..BUT AS YESTERDAY...RECENT RUNS DO SIGNAL HIGHER LATE WEEK RAIN
CHANCES ASSOCIATED BEING DOWNSTREAM OF A BROAD 5H TROUGH/DEVELOPING
GULF TROUGH/LOW. AS OF NOW...THE AIR MASS WILL BE COLD...BUT NOT
COLD ENOUGH TO SUPPORT A WINTRY MIX UP NORTH WHEN THE PRECIPITATION
DOES FALL FRIDAY. IF THIS AIR MASS IS NOT REPRESENTED THAT WELL
(COLDER THAN FORECAST) THEN WE CAN BEGIN TALKING ABOUT A POSSIBLE
RETURN TO A WINTRY MIX OR FZRA OVER OUR FAR INTERIOR. 31
MARINE...
WINDS WILL RELAX OVERNIGHT AS A COLD FRONT APPROACHES AND THE
PRESSURE GRADIENT RELAXES. THE RESPITE FROM STRONGER WINDS WILL BE
SHORT LIVED AS SPEEDS WILL INCREASE RAPIDLY SUNDAY EVENING IN THE
WAKE OF THE COLD FRONT. A SMALL CRAFT ADVISORY WILL LIKELY BE
REQUIRED FOR SUNDAY NIGHT. STILL FEEL THERE IS SOME THREAT FOR SEA
FOG TONIGHT AS SFC WINDS BACK TO THE EAST AND SFC DEW PTS REMAIN
10-12 DEGREES WARMER THAN WATER TEMPS. WITH WIND DECREASING IN
ADVANCE OF THE FRONT...FEEL SEA FOG COULD DEVELOP. OFFSHORE WINDS
WILL PREVAIL THROUGH MONDAY AFTN BEFORE ONSHORE WINDS REDEVELOP MON
NITE AND STRENGTHEN ON TUESDAY MORNING. ANOTHER FRONT WILL CROSS THE
COASTAL WATERS ON TUESDAY EVENING. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 46 48 35 51 44 / 40 50 10 10 60
HOUSTON (IAH) 63 63 39 52 46 / 40 70 20 10 40
GALVESTON (GLS) 57 61 42 50 50 / 30 70 40 10 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 10 PM CST THIS EVENING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...41
AVIATION/MARINE...45
AREA FORECAST DISCUSSION
NWS SEATTLE WA
930 PM PST THU JAN 30 2014
.SYNOPSIS...A WEAK LOW PRESSURE SYSTEM OVER THE AREA WILL MOVE
OVER OREGON BY MIDDAY FRIDAY. HIGH PRESSURE ALOFT WILL MOVE OVER
THE REGION IN ITS WAKE. LOOK FOR DRY NORTHERLY FLOW TO BECOME
ESTABLISHED OVER THE AREA DURING THE DAY FRIDAY. EXPECT THE HIGH
PRESSURE SYSTEM TO WEAKEN ON SATURDAY...ALLOWING ANOTHER WEAK
UPPER LOW TO MOVE OVER THE AREA FROM THE NORTH ON SUNDAY.
&&
.SHORT TERM...
SCATTERED SHOWERS...MORE NUMEROUS OVER THE COAST AND NORTH
INTERIOR...CONTINUED OVER THE CWA. THE PUGET SOUND REGION AND
MUCH OF THE OLYMPICS REMAINED DRY.
MEANWHILE...A STATIONARY FRONT EXTENDED EAST FROM A SURFACE LOW
NW OF CAPE FLATTERY TO ACROSS THE STRAIT OF JUAN DE FUCA AND INTO
THE NORTH CASCADES. THERE WAS A DISORGANIZED AREA OF SHOWERS
ASSOCIATED WITH THIS FEATURE. DEW POINTS HAVE FALLEN INTO THE MID
TO UPPER 20S NORTH OF THIS FRONT. ALSO...WINDS HAVE KICKED UP OUT
OF THE NORTHEAST ACROSS THOSE AREAS PRONE TO FRASER OUTFLOW SUCH
AS SUMAS AND BELLINGHAM.
THE CONCERN IN THE NEAR TERM IS WHETHER THERE WILL BE WET BULB
COOLING EFFECTS OCCURRING ALONG AND JUST SOUTH OF THE FRONTAL
BOUNDARY OVERNIGHT INTO FRI MORNING. THE RUC INDICATED MIXED RAIN
AND SNOW OVER THIS AREA LATE TONIGHT THROUGH ABOUT MIDMORNING FRI.
THE NAM SUGGESTED THAT THE PRECIP MIGHT TRANSITION OVER TO SNOW.
WILL UPDATE THE GRIDS TO INDICATE A MIX OF RAIN AND SNOW ON THE
LOWLANDS IN THE NORTHERN PART OF THE CWA LATER TONIGHT OR FRI
MORNING.
EXPECT THE WEAK UPPER TROF OVER THE AREA TO MOVE INTO OREGON BY
MIDDAY FRI. INCREASED NORTHERLY FLOW ALOFT AND AT THE SURFACE WILL
RESULT IN DRYING ACROSS THE CWA FRI AFTERNOON.
AN UPPER RIDGE WILL PREVAIL OVER THE REGION FRI NIGHT FOR DRY
CONDITIONS. ANTICIPATE A SPLIT FLOW REGIME THIS WEEKEND...WITH THE
SOUTHERN STREAM BEING THE MOST ACTIVE. IT LOOKS LIKE IT SHOULD BE
DRY OVER THE CWA ON SATURDAY EXCEPT FOR A FEW INSTABILITY SHOWERS
OVER THE MOUNTAINS DURING THE DAY. ANOTHER UPPER TROF WILL MOVE
OVER THE REGION FROM THE NORTH ON SUNDAY FOR A THREAT OF SHOWERS
MAINLY OVER THE MOUNTAINS.
.LONG TERM FROM THE PREV DISCUSSION...
THERE IS A CHANCE OF A LITTLE SNOW SHOWER ACTIVITY SUNDAY NIGHT...
THE WRFGFS HAPPENS TO SHOW A BIT IN THE METRO AREA. BUT POPS ARE
LOW AND DRY WEATHER IS AN EVEN BETTER BET...THE SHORTWAVE TROUGH
DROPPING THROUGH THE AREA IS PRETTY MODEST AND MAY NOT GIVE MORE
THAN A PERIOD OF CLOUDS. FOR NOW A GOOD FORECAST FOR THE REST OF
NEXT WEEK IS COOL AND DRY WITH SOME CLOUDS AT TIMES...CALL IT
PARTLY CLOUDY. OVERALL THE GLOBAL MODELS CONTINUED TO SHOW BENIGN
WEATHER...BUT IT IS A WEATHER PATTERN WORTH WATCHING FOR ANY TREND
IN THE MODELS TOWARD A STRONGER SHORTWAVE DROPPING DOWN IN THE NW
FLOW ALOFT...THE 12Z CANADIAN MODEL WAS A BIT MORE INTERESTING AND
DID HAVE A LITTLE LIGHT PRECIP ON TUESDAY. THE LATEST 18Z GFS WAS
DRY TUE-THU.
&&
.AVIATION...AN UPPER TROUGH OVER THE PACIFIC NORTHWEST WILL SHIFT
SOUTH TONIGHT AND FRIDAY WITH FLOW ALOFT BECOMING NORTHERLY. AT THE
SURFACE...HIGH PRESSURE OVER INTERIOR BRITISH COLUMBIA WILL PUSH
SOUTH INTO EASTERN WASHINGTON WHILE A TROUGH OVER WESTERN WASHINGTON
WEAKENS. AIR MASS MOIST AND UNSTABLE.
KSEA...LOW CLOUDS WILL LINGER TONIGHT...PROBABLY LIFTING AND
BREAKING UP A BIT LATER FRIDAY. SOUTH WIND 4-8 KNOTS WILL BECOME
NORTHERLY AROUND FRIDAY MORNING. SCHNEIDER
&&
.MARINE...A TROUGH FROM JUST SOUTH OF VANCOUVER ISLAND ACROSS
NORTH/CENTRAL PUGET SOUND WILL SLOWLY SAG SOUTH AND WEAKEN TONIGHT
AND FRIDAY AS HIGH PRESSURE OVER INTERIOR BRITISH COLUMBIA BUILDS
SOUTH INTO EASTERN WASHINGTON.
HIGH PRESSURE WILL REMAIN INLAND WITH A WEAK TROUGH NEAR THE COAST
SATURDAY THROUGH TUESDAY. OFFSHORE FLOW WILL STRENGTHEN SUNDAY AND
SUNDAY NIGHT AS HIGH PRESSURE REBUILDS OVER INTERIOR BRITISH
COLUMBIA...THEN WEAKEN AGAIN MONDAY AND TUESDAY. SCHNEIDER
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 4 AM PST FRIDAY FOR
THE GRAYS HARBOR BAR.
&&
$$
WWW.WEATHER.GOV/SEATTLE
FOR THE GRAPHICAL AFD...VISIT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
548 PM CST SAT FEB 1 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 222 PM CST SAT FEB 1 2014
CONTINUED COLD WITH JUST SOME LIGHT SNOW AND FLURRIES AT TIMES.
THE FLOW ENTERING NOAM HAS BECOME SPLIT...WITH NRN STREAM
DIVERTING ARND STG RIDGE OVER AK AND SRN STREAM UNDERCUTTING THE
RIDGE AND FLOWING INTO CA/NRN MEXICO. A POSITIVELY TILTED UPR TROF
EXTENDED FM HUDSON BAY INTO THE DESERT W. THE STREAMS REMAINED
SEPARATE AS THE ENTERED THE TROF POSN...THEN MERGED BACK TOGETHER
INTO A STG BROAD SWLY FLOW DOWNSTREAM FM THE TROF AXIS...FM THE
SRN PLAINS TO NEW ENGLAND. CHGS TO THE PATTERN DURING THE FCST
PERIOD WL BE SML...WITH PERHAPS THE EXTENSION OF THE TROF IN THE
SWRN CONUS RETROGRADING A LITTLE AND THE SRN STREAM STRENGTHENING
A BIT.
NLY UPR FLOW ACRS WRN CANADA DOWNSTREAM FM THE AK UPR RIDGE WL
ALLOW A COLD ARCTIC ANTICYCLONE TO RIDGE SWD TOWARD THE NRN
PLAINS...RESULTING IN A CONTINUOUS FEED OF COLD AIR INTO THE FCST
AREA. EXPECT TEMPS TO RUN ABOUT 10-18F DEG BLO NORMAL DURING THE
PERIOD. THOUGH THE COLD WON/T BE AS SEVERE AS SOME OF THE PERIODS
IN JANUARY...IT MAY ACTUALLY BE MORE PERSISTENT AS LESS
ROLLERCOASTERING OF TEMPS IS EXPECTED. THE FCST AREA IS LIKELY TO
REMAIN ALONG THE NRN EDGE OF THE PCPN SHIELDS FM SRN STREAM
SYSTEMS...WITH THE BEST FORCING AND MOISTURE PASSING BY TO OUR S.
SO...PCPN AMNTS ARE LIKELY TO END UP BLO NORMAL.
&&
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 222 PM CST SAT FEB 1 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN AREA OF LOW
PRESSURE MOVING ACROSS NORTHERN INDIANA WHILE A REINFORCING ARCTIC
COLD FRONT IS PUSHING INTO WESTERN WISCONSIN. LIGHT SNOW ON THE
NORTHERN EDGE OF THE SURFACE LOW CONTINUES TO IMPACT NORTHEAST
WISCONSIN EARLY THIS AFTERNOON...AND A RECENT UPTICK IN INTENSITY
POSSIBLY SUGGESTS SUPPORT FROM A NORTHERN STREAM SHORTWAVE CURRENTLY
MOVING EAST ACROSS THE ARROWHEAD OF MINNESOTA. STILL THINKING THAT
MOST IF NOT ALL OF THE LIGHT SNOW FROM THIS SYSTEM WILL DEPART BY
THE START OF THE EVENING. CLEARING IS OCCURRING BEHIND THE ARCTIC
FRONT OVER SOUTHERN MINNESOTA...BUT LIGHT SNOW AND FLURRIES IN THE
SMALL COMMA HEAD OVER NE MINNESOTA WILL LIKELY BRUSH N-C WISCONSIN
LATER THIS AFTERNOON INTO EARLY THIS EVENING. SNOW TRENDS AND
TEMPERATURES ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM.
TONIGHT...WEAK AREA OF LOW PRESSURE WILL QUICKLY EXIT TO THE
NORTHEAST OVER THE EASTERN GREAT LAKES. LIGHT SNOW OVER NORTHEAST
WISCONSIN SHOULD HAVE EXITED BY THE START OF THE EVENING. MEANWHILE
A REINFORCING ARCTIC FRONT WILL SLOWLY MOVE EAST ACROSS THE FORECAST
AREA. SOME CLEARING OBSERVED OVER SOUTHERN MINNESOTA AND EASTERN
DAKOTAS SHOULD ARRIVE INTO CENTRAL AND EAST-CENTRAL WISCONSIN AFTER
THE FRONT PASSES. BUT LOW CLOUDS AND FLURRIES OVER NORTHERN
MINNESOTA SHOULD MOVE ACROSS NORTHERN WISCONSIN SO KEPT A CHANCE OF
FLURRIES IN THE FORECAST THROUGH THE EVENING. COLD ADVECTION WILL
TAKE PLACE BEHIND THE ARCTIC FRONT AND WINDS LOOK MARGINAL FOR
DECOUPLING. COMBINED WITH UNCERTAINTIES WITH CLOUD COVER...THIS
MAKES FOR ANOTHER DIFFICULT TEMP FORECAST. LIKE THE PREVIOUS
FORECAST...WILL SHOW COLDER TEMPS OVER CENTRAL WISCONSIN WHERE THE
BEST CHANCE OF CLEARING WILL OCCUR. BUT IF WINDS DROP OFF...TEMPS
COULD TANK LIKE LAST NIGHT. WILL STAY CONSERVATIVE WITH TEMPS
ACROSS THE EAST WHERE CLOUDS WILL CLEAR LAST. WIND CHILLS MAY STILL
APPROACH ADVISORY CRITERIA FOR A FEW HOURS OVER CENTRAL WISCONSIN
LATE TONIGHT ASSUMING WINDS DO NOT BECOME CALM.
SUNDAY...SURFACE RIDGE AXIS ORIGINATING FROM AN ARCTIC HIGH CENTERED
ACROSS THE CENTRAL PLAINS WILL SHIFT EAST ACROSS THE NORTHERN
MISSISSIPPI VALLEY AND WESTERN GREAT LAKES. THIS RIDGE AXIS SHOULD
PROVIDE A COLD BUT QUIET DAY WITH MOSTLY SUNNY TO PARTLY CLOUDY
CONDITIONS PRESENT. WENT WITH A COMBO OF ECMWF GUIDANCE AND
ALLBLEND FOR HIGHS...WHICH WILL RANGE FROM THE MIDDLE SINGLE DIGITS
TO THE LOWER TEENS ABOVE ZERO. THESE TEMPS WILL BE ABOUT 15 DEGREES
BELOW THE AVERAGE FOR THIS DATE.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 222 PM CST SAT FEB 1 2014
WITH LITTLE CHG TO THE LARGE SCALE PATTERN ANTICIPATED...LAST
NIGHT WAS A GOOD INDICATOR OF THE PITFALLS OF THE NIGHTTIME TEMP
FCSTS. SINCE THE CORE OF THE COLD WL REMAIN TO OUR NW...TEMPS WL
DEPEND ON CLDS AND WINDS. ONCE THE CLDS DISSIPATED AND WIND WENT
CALM LAST NGT...TEMPS ABSOLUTELY TANKED AND ENDED UP NEARLY AS
COLD AS LAST WEEK WHEN THE CORE OF THE COLD WAS DIRECTLY OVER THE
AREA. /OF COURSE...WINDS AND HENCE WIND CHILLS WERE NOT NEARLY AS
LOW THIS TIME ARND./ TRENDED TEMPS DOWN A BIT AT TIMES WHEN IT
LOOKED LIKE THERE COULD BE CLR PERIODS AT NGT. OTHERWISE...STAYED
CLOSE TO BLEND OF TOP PERFORMING GUIDANCE.
PRECIP-WISE...THE M.O. OF THE PAST COUPLE SYSTEMS HAS BEEN FOR
EACH TO LOOK LIKE A BETTER PCPN PRODUCER THAN IT/S PREDECESSOR
WHEN VIEWED FM A FEW DAYS OUT...ONLY TO END UP WITH A SWD SHIFT IN
THE PCPN ON THE MODEL RUNS LEADING UP TO THE EVENT. DESPITE SOME
EARLY MODEL RUNS INDICATING NEAR ADVISORY CRITERIA SNOW TDA IN E-C
WI...WE ARE ENDING UP WITH PRETTY MUCH A NUISANCE EVENT. NOW THE
TUE-WED SYSTEM LOOKS TO BE TRACKING A LITTLE FARTHER S AS
WELL...WITH THE SYSTEM NEXT WEEKEND LOOKING LIKE A BETTER PCPN
PRODUCER. HAVE TO WONDER IF LATER EVENTS WILL END UP PRIMARILY
BYPASSING THE AREA TO THE S AS WELL. AS SUCH...USED NOTHING MORE
THAN CHC POPS IN THE LONG-TERM PART OF THE FCST.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 542 PM CST SAT FEB 1 2014
WEAK ARCTIC FRONT WILL EXIT EASTERN WISCONSIN THIS EVENING.
ASSOCIATED MVFR CIGS SHOULD ALSO EXIT FROM WEST TO EAST DURING THE
EVENING...WITH VFR CONDITIONS AFTER 05Z-06Z. EXCEPTION WILL BE
ACROSS NORTHERN WISCONSIN WHERE SCT-BKN MVFR CIGS MAY PERSIST A FEW
HOURS LONGER AS VERY WEAK UPPER DISTURBANCE PASSES BY TO THE
NORTH OVER LAKE SUPERIOR.
HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE REGION ON SUNDAY
WITH VFR CONDITIONS PREVAILING THROUGH THE REMAINDER OF THE TAF
PERIOD. &&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......ESB
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 233 PM CST FRI JAN 31 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE CENTERED OVER THE NORTHERN MISSISSIPPI VALLEY AND WESTERN
GREAT LAKES REGION. ARCTIC COLD FRONT STRETCHES FROM THE EASTERN
GREAT LAKES TO THE PANHANDLE OF TEXAS. THE BACK EDGE OF MID AND
UPPER LEVEL CLOUDS ARE PASSING ACROSS CENTRAL AND NORTHEAST
WISCONSIN WHERE TEMPS HAVE WARMED INTO THE SINGLE DIGITS ABOVE
ZERO. LOOKING UPSTREAM...NORTHERN STREAM ENERGY IS DIGGING OVER
SOUTH-CENTRAL CANADA...WHILE A SHORTWAVE WITHIN THE SOUTHERN STREAM
IS PRODUCING LOW PRESSURE OVER NEW MEXICO. AS THIS AREA OF LOW PRESSURE
MOVES EAST INTO THE PLAINS AND EVENTUALLY THE NORTHERN OHIO VALLEY
AND INTERACTS WITH THESE SHORTWAVES...PRECIP AND SNOW
CHANCES/IMPACTS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...ARCTIC HIGH PRESSURE WILL BE CENTERED ACROSS THE STATE AT
THE START OF THE EVENING...WITH ONLY SCT MID AND HIGH CLOUDS PASSING
OVER CENTRAL AND EAST-CENTRAL WISCONSIN. WINDS WILL BECOME LIGHT
DURING THE EVENING WHICH WILL SET UP A PERIOD OF GREAT RADIATIONAL
COOLING CONDITIONS UNTIL EARLY OVERNIGHT. TEMPERATURES SHOULD FALL
QUICKLY THIS EVENING AS A RESULT. HAVE DROPPED LOWS ACROSS N-C
WISCONSIN WHERE HAVE CONCERNS DIDNT GO COLD ENOUGH. MID AND HIGH
CLOUDS WILL BE INCREASING AFTER MIDNIGHT AS LOW PRESSURE DEVELOPS
OVER THE SOUTH-CENTRAL PLAINS. SNOW WILL BE LIFTING TO THE
NORTHEAST ALONG A STRENGTHENING WARM FRONT INTO SOUTHERN WISCONSIN.
THINK PRECIP WILL REMAIN SOUTH OF THE FORECAST AREA THROUGH
12Z...BUT WILL LEAVE A SMALL CHANCE IN CASE TIMING IS TOO SLOW.
TEMPS WILL GRADUALLY RISE LATE WITH THE INCOMING CLOUD COVER.
SATURDAY...LOW PRESSURE WILL TRACK OVER CENTRAL ILLINOIS TOWARDS
DETROIT. STRONG FGEN BAND ON THE NOSE OF THE LLJ WILL LEAD TO A
BAND OF HEAVY SNOW OVER NORTHERN ILLINOIS...FAR SE WISCONSIN AND
LOWER MICHIGAN...BUT MODELS POINT TOWARDS ENOUGH SATURATION ALONG
WITH QG FORCING FOR THE NORTHERN EDGE OF THE SNOW TO MOVE ACROSS
CENTRAL AND NORTHEAST WISCONSIN. PRECIP SHOULD BE KNOCKING ON THE
DOOR AROUND 12Z OR SHORTLY THEREAFTER BEFORE SPREADING NORTH ACROSS
ALL BUT NORTH-CENTRAL WISCONSIN. MODEL QPF ARE RELATIVELY
CONSISTENT AND USED A GENERAL BLEND AS IN INPUT INTO THE FORECAST.
WITH SNOW RATIOS OF 16 OR 17 TO 1...LOOKING AT ACCUMS OF 1 TO 3
INCHES SOUTH OF A MARSHFIELD TO MARINETTE LINE...HIGHEST OVER
MANITOWOC COUNTY. MAIN PERIOD OF LIGHT SNOW WILL OCCUR BETWEEN 9AM
AND 3PM...BEFORE PRECIP PULLS OUT LATE IN THE AFTERNOON. UNLIKE THE
PAST FEW STORMS...WINDS SHOULD BE RELATIVELY LIGHT WHICH WILL KEEP
BLOWING AND DRIFTING TO A MINIMUM. WITHOUT THE WIND RELATED
IMPACTS...HAVE DECIDED NOT TO ISSUE HEADLINES FOR THIS EVENT. HIGHS
WILL RANGE FROM THE MID TO UPPER TEENS.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 233 PM CST FRI JAN 31 2014
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST
PERIOD AS RIDGE REMAINS FIRMLY ENTRENCHED ACROSS THE PACIFIC INTO
WESTERN NORTH AMERICA. THIS PATTERN SET UP WILL ALLOW FOR ARCTIC
AIR TO REMAIN ACROSS THE NORTHERN UNITED STATES. MAIN SNOW CHANCES
FOR THIS PERIOD WILL BE TUESDAY INTO WEDNESDAY MORNING AS SYSTEM
PASSES TO THE SOUTH. BELIEVE MODELS ARE TOO FAR SOUTH WITH SYSTEM
BASED ON 850MB THERMAL PROFILE WHICH SHOULD BRING SOME SNOW INTO
THE SOUTHERN TWO THIRDS OF THE FORECAST AREA. ONLY CONCERN WILL
BE HIGH PRESSURE TO THE NORTH THAT WOULD ALLOW FOR DRIER AIR TO
FILTER SOUTHWARD AND HALT THE NORTHWARD ADVANCEMENT OF THE SNOW.
HAVE HIGHEST CHANCES FOR SNOW ACROSS THE SOUTHEAST. LATER SHIFTS
WILL NEED TO MAKE ADJUSTMENTS DEPENDING ON FINAL STORM TRACK AND
THE STRENGTH OF THE RIDGE TO THE NORTH.
MAIN ADJUSTMENTS TO TEMPERATURES DURING THE PERIOD WERE TO LOWER
MINIMUM TEMPERATURES A FEW DEGREES MOST NIGHTS AND TAILOR MAXIMUM
TEMPERATURE GRIDS TO DEPICT OUR USUAL WARM SPOTS.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1123 AM CST FRI JAN 31 2014
ARCTIC HIGH PRESSURE WILL PROVIDE GOOD FLYING WEATHER
THROUGH TONIGHT. THOUGH CLOUDS WILL BE INCREASING OVERNIGHT...WINDS
WILL BE LIGHT. LOW PRESSURE THEN DEVELOPS ACROSS THE OHIO VALLEY
LATE TONIGHT INTO SATURDAY MORNING. LIGHT PRECIPITATION ON THE
NORTHERN EDGE OF THIS SYSTEM WILL SPREAD ACROSS CENTRAL AND
NORTHEAST WISCONSIN DURING THE MORNING HOURS. LOOKING AT 1-3 INCHES
FOR MUCH OF THIS AREA BY THE TIME THE SNOW ENDS LATE SATURDAY
AFTERNOON. HIGHEST AMOUNTS WILL OCCUR NEAR MANITOWOC AND POINTS
SOUTH. VSBYS TO FALL TO IFR OR HIGH END LIFR ONCE THE SNOW ARRIVES.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1025 PM MST THU JAN 30 2014
.UPDATE...
ISSUED AT 903 PM MST THU JAN 30 2014
FRONT PUSHED THROUGH THE CHEYENNE AREA AROUND THE 00Z TIME FRAME.
LATEST SURFACE ANALYSIS SHOWING A SURFACE WAVE JUST SOUTH OF THE
WYOMING BORDER IN NORTHERN COLORADO THIS EVENING AT 9 PM. LOOKING
LIKE THIS WILL BE THE MAIN SHOW AS IT MOVES INTO THE SOUTHERN
PANHANDLE. LATEST MOSAIC RADAR HAS SNOW ENDING IN CARBON AND
ALBANY COUNTIES THIS EVENING WITH THE HEAVIEST SNOW RIGHT AROUND
THE CHEYENNE AREA. WENT AHEAD AND CANCELLED THE SNOW ADVISORIES
OUT WEST AND UP TO THE NORTH OF CHEYENNE THIS EVENING. WILL WAIT
ANOTHER HOUR OR SO TO SEE WHAT THAT SURFACE WAVE DOES BEFORE
DEALING WITH THE WINTER HEADLINES ACROSS SOUTHEAST WYOMING.
UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 300 PM MST THU JAN 30 2014
WIDESPREAD SNOW EVENT STILL ON TRACK TO BEGIN OVER THE NEXT FEW
HOURS AND CONTINUE THROUGH FRIDAY MORNING. HOWEVER...THERE HAS BEEN
A SOUTHWARD SHIFT IN THE MODEL QPF OVER THE PAST DAY THAT
DEFINITELY CAUSES SOME UNCERTAINTY IN SNOWFALL AMOUNTS.
WATER VAPOR IMAGERY SHOWS A STRONG JET EXTENDING FROM SOUTHERN
CALIFORNIA INTO COLORADO WITH AN EMBEDDED SHORTWAVE OVER NORTHERN
UTAH. SFC FRONT HAS MOVED OVER MUCH OF THE PLAINS WITH LOW CLOUDS
QUICKLY FILLING IN BEHIND IT IN THE UPSLOPE. AS THE SHORTWAVE
MOVES ACROSS COLORADO THIS EVENING...ISENTROPIC LIFT INCREASES
OVER THE REGION. HOWEVER...THE MODELS SHOW THE BEST QG LARGE
SCALE ASCENT OVER THE NORTHERN HALF OF COLORADO. IN
ADDITION...MIDLEVEL FRONTOGENESIS IS OVER NORTHERN COLORADO FROM
00-06Z...SO THE HIGHEST QPF WOULD BE ALONG AND JUST SOUTH OF THIS
AXIS...OR WELL SOUTH OF THE CWA. WITH ONLY UPSLOPE AND LLVL
ISENTROPIC LIFT AND A LACK OF REALLY ANY OTHER FORCING
MECHANISM FOR DEEP ASCENT...BEGINNING TO WONDER HOW HIGH SNOWFALL
AMOUNTS WILL REALLY BE. A LOOK AT THE MODEL TREND IN QPF OVER THE
PAST DAY IS ALSO NOT ENCOURAGING FOR LARGER AMOUNTS. YESTERDAY THE AXIS
OF HIGHEST QPF WAS ALONG THE COLORADO BORDER AND NOW WITH THE 12Z
RUN IT IS ALONG AND JUST NORTH OF INTERSTATE 70 IN COLORADO.
CONSIDERING ALL THESE FACTORS...REDUCED THE SNOWFALL TOTALS BY
ABOUT 2 INCHES IN MOST AREAS FOR THE EVENT. THIS LEAVES MANY
LOWER ELEVATION LOCATIONS ALONG AND WEST OF THE LARAMIE RANGE
WITH 1 TO 3 INCHES. THE HIGHEST SNOWFALL AMOUNTS STILL LOOK TO BE
NEAR THE COLORADO BORDER WITH GENERALLY 4 TO 6 INCHES OVER LOWER
ELEVATIONS. SINCE UPSLOPE IS MAXIMIZED IN THE SOUTHERN LARAMIE
RANGE AND ITS ADJACENT EASTERN FOOTHILLS...WILL LIKELY SEE A FEW
MORE INCHES THERE. WILL KEEP THE WINTER WEATHER HIGHLIGHTS
GOING...BUT THEY ARE REALLY BEGINNING TO LOOK
MARGINAL...ESPECIALLY CONSIDERING THAT WINDS WILL GENERALLY BE
BELOW 15 MPH AND BLOWING SNOW NOT MUCH OF A CONCERN. SNOW WILL
BEGIN TO TAPER OFF AFTER 12Z FRI AS THE LIFT DECREASES
CONSIDERABLY. NOT A WHOLE LOT OF WIND TOMORROW...BUT TEMPS WILL
DEFINITELY BE COLD WITH SNOW ON THE GROUND AND MOSTLY CLOUDY
SKIES.
SECONDARY SHORTWAVE IS STILL PROGGED TO MOVE ACROSS SOUTHERN
COLORADO ON FRIDAY AFTERNOON AND NIGHT. BEST FORCING IS ONCE AGAIN
OVER COLORADO WITH THE QPF LARGELY REMAINING SOUTH OF THE COLORADO
BORDER. ANOTHER SHORTWAVE DROPS DOWN OVER WYOMING AND MONTANA
DURING THE DAY ON SAT. DID INCREASE POPS TO SLIGHT CHANCE OR
LOW END CHANCE ON SAT. SAT WILL FEATURE ANOTHER 5 DEGREE DROP IN
HIGHS AS 700MB TEMPS FALL TO -16C BY THE AFTN.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 300 PM MST THU JAN 30 2014
SNOW WILL LINGER THROUGH SATURDAY NIGHT ESPECIALLY IN THE MOUNTAINS
AND ALONG THE CHEYENNE RIDGE AS A SHORTWAVE MOVES OVERHEAD WITH
NORTH-NORTHEASTERLY UPSLOPE FLOW IN PLACE. SHOULD SEE ANOTHER 1 TO 2
INCHES OF ACCUMULATION IN THE MOUNTAINS...ESPECIALLY ALONG THE
EASTERN SLOPE OF THE LARAMIE RANGE...WITH AN INCH OR LESS
ELSEWHERE. DRY NORTHWEST FLOW WILL THEN MOVE OVERHEAD FOR SUNDAY
WITH CONTINUED COOL TEMPS. WESTERLY WINDS WILL BE ON THE INCREASE
THROUGH THIS TIME AS WELL...BUT SHOULD REMAIN ONLY ON THE BREEZY
SIDE AS 700 MB WINDS ARE PROGGED TO BE 30 TO 35 KTS. A STRONG UPPER
LOW WILL DIG INTO THE DESERT SOUTHWEST ON MONDAY WITH WEAK ENERGY
MOVING UP INTO COLORADO AHEAD OF THE DIGGING LOW. CYCLOGENESIS
OCCURRING OVER COLORADO THROUGH THIS TIME WILL INDUCE NORTHEASTERLY
SFC WINDS OVER SOUTHEAST WYOMING AND WESTERN NEBRASKA. THIS UPSLOPE
COMPONENT COMBINED WITH THE WEAK UPPER LEVEL ENERGY MOVING UP FROM
THE SOUTHWEST SHOULD BRING ANOTHER ROUND OF LIGHT SNOW TO THE
FORECAST AREA MONDAY EVENING THROUGH TUESDAY. ENERGETIC NW FLOW WILL
THEN MOVE OVERHEAD FOR WEDNESDAY AND SHOULD PRODUCE MOUNTAIN SNOW
SHOWERS WITH A FEW MOVING OFF ONTO THE NEARBY EASTERN PLAINS THROUGH
THE DAY. TEMPERATURES WILL OVERALL REMAIN QUITE COLD THROUGH
MIDWEEK...WITH TEENS AND 20S EXPECTED FOR MAX TEMPS AND SINGLE
DIGITS TO BELOW ZERO READINGS FOR OVERNIGHT LOWS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1017 PM MST THU JAN 30 2014
AREA OF SNOW PRODUCING IFR TO LIFR CONDITIONS CONTINUES ACROSS
EXTREME SOUTHEAST WYOMING ALONG THE INTERSTATE 80 CORRIDOR FROM
SIDNEY TO CHEYENNE AND IN THE CENTRAL NEBRASKA PANHANDLE TO
INCLUDE KBFF AND KAIA. LATEST HRRR FORECAST KEEPS IFR CONDITIONS
THROUGH 12Z HERE AT KCYS AND MAYBE A LITTLE LATER IN THE SOUTHERN
PANHANDLE.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MST THU JAN 30 2014
NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. WIDESPREAD SNOW
IS EXPECTED TO DEVELOP THIS EVENING AND PERSIST INTO FRIDAY
MORNING. A COLD PATTERN WILL BE IN PLACE OVER THE REGION...WITH
TEMPS 10-15 DEGREES BELOW NORMAL. WINDS WILL ALSO BE WEAK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 8 AM MST FRIDAY FOR WYZ112-114-
116>119.
NE...WINTER STORM WARNING UNTIL 8 AM MST FRIDAY FOR NEZ020-054.
WINTER WEATHER ADVISORY UNTIL 8 AM MST FRIDAY FOR NEZ003-019-021-
055-096.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...FINCH
LONG TERM...RJM
AVIATION...CLAYCOMB
FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
330 AM EST SUN FEB 2 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1238 AM EST SUN FEB 2 2014
QUICK UPDATE TO PUT OUT WINTER WEATHER ADVISORY FOR PARTS OF
CENTRAL AND NORTHERN FORECAST AREA. RADAR SHOWED BAND OF HEAVY
SNOW THROUGH CRAWFORDSVILLE...FRANKFORT...AND STRETCHING NORTHEAST
TO MARION INDIANA. 3 INCHES OF SNOW WERE ALREADY REPORTED WITH
THIS BAND AND HRRR AND RAP SHOW THE BAND HOLDING TOGETHER FOR
ANOTHER COUPLE OF HOURS OVER ROUGHLY THE SAME AREA SO THINK 4-5
INCHES WITH ISOLATED 6 IS POSSIBLE. SOUTH OF THIS BAND A MIX OF
RAIN...FREEZING RAIN AND SLEET WERE OCCURRING AND SHORT RANGE
MODELS SHOW A WAVE OF ENHANCEMENT IN THIS AREA IN A FEW HOURS.
WITH TEMPERATURES SLOWLY DROPPING THOUGHT THIS COULD RESULT IN A
TENTH OF AN INCH OF ICE ACCUMULATION AND PERHAPS EVEN ISOLATED
LOCATIONS OF TWO TENTHS OF AN INCH. THIS WILL BE FOLLOWED BY
SNOW...CURRENT INDICATIONS ARE AN INCH OR TWO BUT CAN/T RULE OUT
ISOLATED THREE DEPENDING UPON PRECIP TYPE WITH THE ENHANCED WAVE
ARRIVES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 323 AM EST SUN FEB 02 2014
FOCUS WILL BE ON TIMING AND PRECIPITATION TYPE WITH ANOTHER SOUTHERN
STORM SYSTEM THAT WILL EFFECT CENTRAL INDIANA AS WELL AS
TEMPERATURES IN THE WAKE OF THE MUCH TALKED ABOUT TUESDAY AND
TUESDAY NIGHT SYSTEM.
EXTENDED MODELS ARE IN GOOD AGREEMENT IN PUSHING THE LOW PRESSURE
SYSTEM...THAT WILL TRACK ACROSS EASTERN KENTUCKY TUESDAY NIGHT...OUT
TO SEA BY 18Z WEDNESDAY ALLOWING ANY LINGERING SNOW TO END. LOW POPS
FOR WEDNESDAY PER THE REGIONAL ALLBLEND LOOKS GOOD. THEN...ARCTIC
HIGH PRESSURE WILL BUILD IN FROM WESTERN CANADA AND MOVE ACROSS
CENTRAL INDIANA ON FRIDAY. THIS TREND IS SLOWER THAN PREVIOUS MODEL
RUNS AND ALL MODELS KEEP IT DRY FRIDAY. THEN...BIG DIFFERENCES IN
TIMING TAKE PLACE AS THE ECMWF IS MUCH QUICKER...AROUND 24 HOURS IN
FACT...SPINNING UP A SOUTHERN STATES SYSTEM AHEAD OF AN APPROACHING
SOUTHERN PLAINS UPPER TROUGH AND BRINGING THE SURFACE SYSTEM INTO
THE OHIO VALLEY. ECMWF TENDS TO DO BETTER WITH DAYS 6 AND 7 AND
MATCHES UP BETTER WITH THE REGIONAL ALLBLEND THAT HAS PRECIPITATION
ACROSS THE ENTIRE FORECAST AREA ON FRIDAY NIGHT AND THROUGH THE
WEEKEND.
LOOKING AT BUFKIT...SOUNDINGS FAVOR ALL SNOW AT THIS POINT...SO WILL
NOT MESS WITH ANY MIXED PRECIPITATION AT THIS POINT ACROSS THE SOUTH.
AGREE WITH VERY COLD ALLBLEND TEMPERATURES. WITH ARCTIC AIR BUILDING
IN...EXPECTED SNOW COVER AND SOME BREAKS IN THE CLOUDS BY WEDNESDAY
NIGHT...CERTAINLY CAN ENVISION BELOW NORMAL NIGHTTIME TEMPERATURES
ONCE AGAIN MID TO LATE WEEK.
&&
.AVIATION /DISCUSSION FOR THE 020900Z IND TAF UPDATE/...
ISSUED AT 330 AM EST SUN FEB 2 2014
HEAVIER SNOW AND SLEET WILL BE MOVING IN BY 09Z PER RADAR. WENT WITH
IFR CONDITONS AND MAY HAVE TO EVENTUALLY GO LOWER. WINDS WILL BE
NORTH AROUND 10 KNOTS. EXPECTED THE SNOW TO END TOWARD 12Z AND
CONDITIONS TO GRADUALLY IMPROVE TO MVFR TOWARD 15Z.
PREVIOUS DISCUSSION FOLLOWS...
LOWER CONFIDENCE FORECAST WITH RESPECT TO PRECIPITATION TYPES
OVERNIGHT AS LOW LEVEL COLD ADVECTION FIGHTS WITH OVERRUNNING ALONG
A FRONTAL ZONE.
APPEARS RAIN/SNOW LINE HAS BEEN PROGRESSING SLOWLY SOUTHEAST THROUGH
THE EVENING HOURS. MODELS SUGGEST A STRONGER PUSH OF WARM ADVECTION
ALOFT POSSIBLE OVER THE NEXT 4-6 HOURS ASSOCIATED WITH A WEAK
DISTURBANCE...WHICH MAY SERVE TO SLOW DOWN THE SOUTHEAST PUSH OF THE
RAIN/SNOW LINE TEMPORARILY.
BEST GUESS AT THIS TIME IS FOR THE RAIN/SNOW LINE TO BE IN THE
VICINITY OF KIND/KHUF BY ISSUANCE TIME...WITH A SLOW PUSH TOWARDS
KBMG BY 021000Z. MAY STILL BE A PERIOD OF FREEZING RAIN/SLEET
EMBEDDED WITHIN THE TRANSITION ZONE...BUT SO FAR NOT SEEING MUCH IN
THE WAY OF GROUND REPORTS AT THIS TIME. MOST OF THE PRECIPITATION
SHOULD BE OVER AROUND DAYBREAK SUNDAY.
IN GENERAL...EXPECTING IFR CEILINGS/OCCASIONAL IFR VISIBILITY
RESTRICTIONS OVERNIGHT...ESPECIALLY IN THE SNOW AREAS...WITH
CONDITIONS IMPROVING BY LATE SUNDAY MORNING AS DRIER AIR ADVECTS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR INZ030-
031-036>049-051>057-060.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...CP
SHORT TERM...RYAN
LONG TERM...MK
AVIATION...JAS/MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
323 AM EST SUN FEB 2 2014
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1238 AM EST SUN FEB 2 2014
QUICK UPDATE TO PUT OUT WINTER WEATHER ADVISORY FOR PARTS OF
CENTRAL AND NORTHERN FORECAST AREA. RADAR SHOWED BAND OF HEAVY
SNOW THROUGH CRAWFORDSVILLE...FRANKFORT...AND STRETCHING NORTHEAST
TO MARION INDIANA. 3 INCHES OF SNOW WERE ALREADY REPORTED WITH
THIS BAND AND HRRR AND RAP SHOW THE BAND HOLDING TOGETHER FOR
ANOTHER COUPLE OF HOURS OVER ROUGHLY THE SAME AREA SO THINK 4-5
INCHES WITH ISOLATED 6 IS POSSIBLE. SOUTH OF THIS BAND A MIX OF
RAIN...FREEZING RAIN AND SLEET WERE OCCURRING AND SHORT RANGE
MODELS SHOW A WAVE OF ENHANCEMENT IN THIS AREA IN A FEW HOURS.
WITH TEMPERATURES SLOWLY DROPPING THOUGHT THIS COULD RESULT IN A
TENTH OF AN INCH OF ICE ACCUMULATION AND PERHAPS EVEN ISOLATED
LOCATIONS OF TWO TENTHS OF AN INCH. THIS WILL BE FOLLOWED BY
SNOW...CURRENT INDICATIONS ARE AN INCH OR TWO BUT CAN/T RULE OUT
ISOLATED THREE DEPENDING UPON PRECIP TYPE WITH THE ENHANCED WAVE
ARRIVES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 323 AM EST SUN FEB 02 2014
FOCUS WILL BE ON TIMING AND PRECIPITATION TYPE WITH ANOTHER SOUTHERN
STORM SYSTEM THAT WILL EFFECT CENTRAL INDIANA AS WELL AS
TEMPERATURES IN THE WAKE OF THE MUCH TALKED ABOUT TUESDAY AND
TUESDAY NIGHT SYSTEM.
EXTENDED MODELS ARE IN GOOD AGREEMENT IN PUSHING THE LOW PRESSURE
SYSTEM...THAT WILL TRACK ACROSS EASTERN KENTUCKY TUESDAY NIGHT...OUT
TO SEA BY 18Z WEDNESDAY ALLOWING ANY LINGERING SNOW TO END. LOW POPS
FOR WEDNESDAY PER THE REGIONAL ALLBLEND LOOKS GOOD. THEN...ARCTIC
HIGH PRESSURE WILL BUILD IN FROM WESTERN CANADA AND MOVE ACROSS
CENTRAL INDIANA ON FRIDAY. THIS TREND IS SLOWER THAN PREVIOUS MODEL
RUNS AND ALL MODELS KEEP IT DRY FRIDAY. THEN...BIG DIFFERENCES IN
TIMING TAKE PLACE AS THE ECMWF IS MUCH QUICKER...AROUND 24 HOURS IN
FACT...SPINNING UP A SOUTHERN STATES SYSTEM AHEAD OF AN APPROACHING
SOUTHERN PLAINS UPPER TROUGH AND BRINGING THE SURFACE SYSTEM INTO
THE OHIO VALLEY. ECMWF TENDS TO DO BETTER WITH DAYS 6 AND 7 AND
MATCHES UP BETTER WITH THE REGIONAL ALLBLEND THAT HAS PRECIPITATION
ACROSS THE ENTIRE FORECAST AREA ON FRIDAY NIGHT AND THROUGH THE
WEEKEND.
LOOKING AT BUFKIT...SOUNDINGS FAVOR ALL SNOW AT THIS POINT...SO WILL
NOT MESS WITH ANY MIXED PRECIPITATION AT THIS POINT ACROSS THE SOUTH.
AGREE WITH VERY COLD ALLBLEND TEMPERATURES. WITH ARCTIC AIR BUILDING
IN...EXPECTED SNOW COVER AND SOME BREAKS IN THE CLOUDS BY WEDNESDAY
NIGHT...CERTAINLY CAN ENVISION BELOW NORMAL NIGHTTIME TEMPERATURES
ONCE AGAIN MID TO LATE WEEK.
&&
.AVIATION /DISCUSSION FOR THE 020600Z TAFS/...
ISSUED AT 1130 PM EST SAT FEB 1 2014
LOWER CONFIDENCE FORECAST WITH RESPECT TO PRECIPITATION TYPES
OVERNIGHT AS LOW LEVEL COLD ADVECTION FIGHTS WITH OVERRUNNING ALONG
A FRONTAL ZONE.
APPEARS RAIN/SNOW LINE HAS BEEN PROGRESSING SLOWLY SOUTHEAST THROUGH
THE EVENING HOURS. MODELS SUGGEST A STRONGER PUSH OF WARM ADVECTION
ALOFT POSSIBLE OVER THE NEXT 4-6 HOURS ASSOCIATED WITH A WEAK
DISTURBANCE...WHICH MAY SERVE TO SLOW DOWN THE SOUTHEAST PUSH OF THE
RAIN/SNOW LINE TEMPORARILY.
BEST GUESS AT THIS TIME IS FOR THE RAIN/SNOW LINE TO BE IN THE
VICINITY OF KIND/KHUF BY ISSUANCE TIME...WITH A SLOW PUSH TOWARDS
KBMG BY 021000Z. MAY STILL BE A PERIOD OF FREEZING RAIN/SLEET
EMBEDDED WITHIN THE TRANSITION ZONE...BUT SO FAR NOT SEEING MUCH IN
THE WAY OF GROUND REPORTS AT THIS TIME. MOST OF THE PRECIPITATION
SHOULD BE OVER AROUND DAYBREAK SUNDAY.
IN GENERAL...EXPECTING IFR CEILINGS/OCCASIONAL IFR VISIBILITY
RESTRICTIONS OVERNIGHT...ESPECIALLY IN THE SNOW AREAS...WITH
CONDITIONS IMPROVING BY LATE SUNDAY MORNING AS DRIER AIR ADVECTS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR INZ030-
031-036>049-051>057-060.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...CP
SHORT TERM...RYAN
LONG TERM...MK
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
126 AM EST SUN FEB 2 2014
.SYNOPSIS...
ISSUED AT 526 PM EST SAT FEB 1 2014
A SLOW MOVING UPPER LEVEL SYSTEM WILL SHIFT EASTWARD
TONIGHT...EVENTUALLY SHIFTING PRECIPITATION EAST OF THE AREA LATE
TONIGHT INTO EARLY SUNDAY MORNING. COLDER AIR FILTERING INTO THE
REGION TONIGHT WILL ALLOW FOR PRECIPITATION TO CHANGEOVER TO SNOW
BEFORE ENDING ACROSS NORTHEAST INDIANA...NORTHWEST OHIO...AND
SOUTHEAST LOWER MICHIGAN. QUIET CONDITIONS ARE EXPECTED ON SUNDAY
AND MONDAY AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
HOWEVER...A STRONG STORM SYSTEM IS EXPECTED TO ORGANIZE ACROSS THE
SOUTHERN ROCKIES ON MONDAY...AND THEN BRING A POTENTIAL OF SOME
SIGNIFICANT SNOWFALL TO THE REGION FROM TUESDAY THROUGH EARLY WEDNESDAY.
&&
.UPDATE...
ISSUED AT 750 PM EST SAT FEB 1 2014
SFC REFLECTION HAS NOW TRACKED INTO FAR SOUTHEAST ONTARIO ALLOWING
LOCATIONS ACROSS NORTHWEST HALF OF THE AREA TO EXPERIENCE WIND
SHIFT TO THE NORTHWEST. PRECIP HAS TRANSITIONED BACK TO SNOW WITH
PERHAPS A VERY BRIEF PERIOD OF SOME SLEET BEFORE CHANGING OVER TO
SNOW. EXPECTING THIS BRIEF PERIOD OF MIXED PRECIP TO BE SHORT
LIVED AS IT PROGRESSES EASTWARD THROUGH THE REMAINDER OF THE
EVENING GIVEN VERY WEAK NATURE TO WARM LAYER ALOFT. MAIN LOW LEVEL
MOIST TONGUE WILL HAVE SHIFTED EAST OF THE AREA BY THE TIME PRECIP
CHANGES OVER TO SNOW...WITH SOME INITIALLY LOW SNOW:LIQUID RATIOS
AS THIS TRANSITION OCCURS. THIS SHOULD TEMPER ACCUMULATIONS
OVERNIGHT ALTHOUGH GIVEN POTENTIAL FOR SOME MODERATE PRECIP RATES
AT LEAST THROUGH 06Z...WILL HAVE TO KEEP AN EYE FOR SOME MORE
LOCALIZED HEAVIER SNOWFALL RATES. WHILE MOST OF ADDITIONAL SNOW
ACCUMULATION IS ANTICIPATED SOUTHEAST OF THE CURRENT WINTER STORM
WARNING AREA...HAVE OPTED TO CONTINUE THIS HEADLINE FOR NOW GIVEN
CONTINUED PERIODS OF SNOW AND SLUSHY/ICY ROAD CONDITIONS. WITH A
LOW AMPLITUDE PATTERN IN PLACE AND INITIAL SHORT WAVE NOW MORE
SHEARED IN NATURE AND RACING ACROSS SOUTHEAST ONTARIO...MAY TEND
TO SEE LOW LEVEL TROUGH SLOW ITS EASTWARD PROGRESSION OVERNIGHT
WHICH ALREADY SEEMS WELL HANDLED IN GRIDDED FORECAST. 00Z RAP
INITIALIZATION SEEMS TO HAVE PICKED UP ON A WEAK SHORT WAVE ACROSS
NORTHEAST ILLINOIS WHICH WILL TRACK INTO SOUTHERN LOWER MICHIGAN
OVERNIGHT. THIS FEATURE MAY RESULT IN SOME LOW/MID LEVEL
FRONTOGENESIS RESPONSE ACROSS THE AREA OVERNIGHT. NAM CROSS
SECTIONS DO ALSO DEPICT SOME ELEVATED INSTABILITY LINGERING
ESPECIALLY ACROSS SOUTHEAST THIRD OF THE AREA IN THE 06Z-12Z
TIMEFRAME. THUS...SOME LOW END CONCERN FOR BAND OF ENHANCED SNOW
ACROSS THESE LOCATIONS WHERE SOME WEAK-MODERATE 850-700 HPA FGEN
FORCING IS ANTICIPATED OVERNIGHT IN PROXIMITY TO WEAKER STABILITY
ALOFT. HOWEVER AT THIS TIME...GIVEN RELATIVELY LOW SNOW:LIQUID
RATIOS AND DEEPER MOISTURE ADVECTING EAST OF THE AREA...WILL LIMIT
ACCUMS TO 1 TO 3 INCHES. UPDATED FORECAST SENT TO ACCOUNT FOR
CURRENT POP/TEMP TRENDS.
&&
.SHORT TERM...(THROUGH TONIGHT)
ISSUED AT 337 PM EST SAT FEB 1 2014
...MESSY AFTERNOON/EVENING ON TAP FOR THE AREA...
AS OF 230 PM...LOCATIONS SOUTH OF A KANKAKEE...TO GOSHEN TO ANGOLA
LINE WERE SEEING ALL RAIN AS TEMPERATURES WERE IN THE MIDDLE 30S TO
NEAR 40 (FAR SOUTHEAST). PRIOR TO MIXING/SWITCHOVER...NUMEROUS
REPORTS OF 3 TO 5 INCHES OF SNOW CAME IN ACROSS THE WARNING AREA
WITH ANYWHERE FROM 1 TO 4 INCHES. BROAD AREA OF LOW PRESSURE WAS
LOCATED SOMEWHERE NEAR WHITE COUNTY...A BIT FURTHER NORTHWEST THAN
EXPECTED. RUC HAS BEEN HANDLING MANY OF THE FINER DETAILS QUITE WELL
AND WAS USED ALMOST EXCLUSIVELY FOR THE FORECAST INTO THIS EVENING.
THE LOW SHOULD TRACK ACROSS THE CENTRAL PORTIONS OF THE CWA BUT
ALSO SHOWING A FASTER TREND SO PREVIOUSLY THOUGHT CHANGE OVER TIMES
STILL LOOK REASONABLE. AS THE TRANSITION COMMENCES A BRIEF PERIOD OF
SLEET/FREEZING RAIN MAY OCCUR. ONCE THIS OCCURS...SEVERAL HOURS OF
SNOW IS EXPECTED WITH ADDITIONAL QPF VALUES OF ROUGHLY ONE QUARTER
INCH OR SO IN FAR NW AREAS TO A BAND OF THREE QUARTERS OF AN INCH OR
MORE IN SE HALF OR SO. MUCH OF THIS HEAVIER PRECIP WILL FALL IN THE
FORM OF RAIN...BUT MUCH LIKE FURTHER NW A QUARTER TO THIRD OF AN
INCH WILL LIKELY FALL AS SNOW. JUST AS WAS THE CASE EARLIER
TODAY...TOO MUCH UNCERTAINTY CONTINUES IN TRANSITION TO WARRANT ANY
HEADLINE CHANGES. IT COULD BE CLOSE FOR FULL WARNING CRITERIA BEING
MET IN SOME AREAS...BUT WARNING WAS ISSUED FOR A COMBINATION OF
EARLIER SNOW AND EXPECTED SNOW BEHIND THE LOW SO SHOULD WORK OUT FOR
THE MOST PART. FURTHER UPDATES AND REFINEMENTS ARE LIKELY INTO THIS
EVENING. NEEDLESS TO SAY...ONCE TEMPS START TO FALL..ROAD CONDITIONS
WILL BECOME MESSY AND VERY SLIPPERY WELL INTO THE OVERNIGHT HOURS.
&&
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 337 PM EST SAT FEB 1 2014
ENERGETIC IMPULSE LADEN FLW EMBEDDED WITHIN PROJECTED NEG PNA PATTN
ACRS NOAM SPELLS HIGH IMPACT WX ACRS THE OH VALLEY THIS PD. OF NOTE
CONTS TO BE W/SYS SEEN THIS AFTN ON VAPOR OUT NR 42N/137W WHICH DIGS
SEWD INTO NRN BAHA ON MON AND THEN LIFTS OUT THROUGH THE LWR OH
VALLEY AS LARGER SCALE ARCTIC STREAM SW DROPS SWD INTO THE WRN US.
PRONOUNCED POLAR RIDGING BLDG IN WAKE OF SHRT TERM SYS PASSAGE TO
PROVIDE A BRIEF DRY BUT COLD RESPITE FROM WINTERS ONSLAUGHT. HWVR
DEEP SRN PLAINS EJECTION POINT AND STG GOMEX RTN FLW INTO SRN
PERIPHERY OF RETREATING SFC RIDGE LOOK TO PROVIDE FOR SIG CYCLONE
DVLPMNT OVR THE LWR MS VALLEY EARLY TUE AND UP THROUGH THE ERN OH
VALLEY ON WED AS EXEMPLIFIED IN STABLE SPECTRAL TRACK. DETAILS AS
YET TO BE IRONED OUT BUT SIG IMPACTS XPCD BOTH W/WIND AND SNOW
PARTICULARLY TUE AFTN-WED AM.
OTRWS ARCTIC RIDGE BLDS EWD OUT OF THE PLAINS THU-FRI W/VERY COLD
TEMPS YET LOOKS TO SET THE STAGE FOR YET ANOTHER SIG OH VALLEY
CYCLONE NXT WEEKEND AS DEEP WRN TROUGH RELOADS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 110 AM EST SUN FEB 2 2014
AN EMBEDDED SHORT WAVE TROF WAS HELPING TO KEPT LIGHT SNOW
LINGERING AT FWA. THE LATEST 12KM/NAM APPEARS TO BE HANDLING THIS
SYSTEM REASONABLY WELL...WITH THE SHORT WAVE PASSING ACROSS THE
AREA EARLY THIS MORNING. MAY HAVE BEEN A LITTLE TOO OPTIMISTIC ON
ENDING THE SNOW AT 08Z AT FWA...ALTHOUGH SUBSIDENCE WILL INCREASE
BEHIND THE TROF LATER THIS MORNING...AND SHOULD ALLOW SNOW TO END
AND CONDITIONS TO IMPROVE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...MARSILI
SYNOPSIS...MARSILI
SHORT TERM...FISHER
LONG TERM...T
AVIATION...SKIPPER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1245 AM EST SUN FEB 2 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1238 AM EST SUN FEB 2 2014
QUICK UPDATE TO PUT OUT WINTER WEATHER ADVISORY FOR PARTS OF
CENTRAL AND NORTHERN FORECAST AREA. RADAR SHOWED BAND OF HEAVY
SNOW THROUGH CRAWFORDSVILLE...FRANKFORT...AND STRETCHING NORTHEAST
TO MARION INDIANA. 3 INCHES OF SNOW WERE ALREADY REPORTED WITH
THIS BAND AND HRRR AND RAP SHOW THE BAND HOLDING TOGETHER FOR
ANOTHER COUPLE OF HOURS OVER ROUGHLY THE SAME AREA SO THINK 4-5
INCHES WITH ISOLATED 6 IS POSSIBLE. SOUTH OF THIS BAND A MIX OF
RAIN...FREEZING RAIN AND SLEET WERE OCCURRING AND SHORT RANGE
MODELS SHOW A WAVE OF ENHANCEMENT IN THIS AREA IN A FEW HOURS.
WITH TEMPERATURES SLOWLY DROPPING THOUGHT THIS COULD RESULT IN A
TENTH OF AN INCH OF ICE ACCUMULATION AND PERHAPS EVEN ISOLATED
LOCATIONS OF TWO TENTHS OF AN INCH. THIS WILL BE FOLLOWED BY
SNOW...CURRENT INDICATIONS ARE AN INCH OR TWO BUT CAN/T RULE OUT
ISOLATED THREE DEPENDING UPON PRECIP TYPE WITH THE ENHANCED WAVE
ARRIVES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 257 PM EST SAT FEB 1 2014
FOCUS REMAINS POSSIBLE WINTER STORM TUESDAY INTO WEDNESDAY.
CONTINUE TO PREFER A BLEND OF GUIDANCE WITH LESS RELIANCE ON
SOMEWHAT LESS CONSISTENT GFS. GFS LOW TRACK HAS SHIFTED SLIGHTLY
SOUTHEAST AND EURO SLIGHTLY NORTHWEST...ALTHOUGH EURO REMAINS
CONSISTENTLY THE COLDER MODEL AND GFS WARMER ODDLY ENOUGH. GFS
ENSEMBLE MEMBERS REMAIN LOOSELY CLUSTERED BUT AROUND A FURTHER
SOUTHEAST TRACK THAN PREVIOUS DAYS...BUT THIS HAS YET TO TRANSLATE
TO A COLDER SOLUTION IN THE LOW LEVELS.
AS SUCH...WILL CONTINUE WITH ALL SNOW MAINLY NORTH/NORTHWEST OF
INDY...WITH A CHANCE OF SLEET/FREEZING RAIN MIXING IN A SWATH
SOUTH OF THIS...AND FREEZING RAIN/SLEET WITH A CHANCE OF SNOW
ACROSS THE FAR SOUTH LATE TUESDAY INTO TUESDAY EVENING. ALL PRECIP
AFTER 06Z WEDNESDAY LIKELY SNOW OR QUICKLY TRANSITIONING TO SNOW.
MESOSCALE FEATURES WILL BE IN PLAY AND AS SUCH AMOUNTS REMAIN VERY
DIFFICULT TO PINPOINT. BANDING WILL BE AN ISSUE WHICH COULD IMPACT
BOTH AMOUNTS AND PRECIP TYPE OWING TO DYNAMIC EFFECTS.
MESSAGE REMAINS THE SAME. CENTRAL INDIANA RESIDENTS SHOULD BE
PREPARED FOR A POSSIBLE WINTER STORM BEGINNING TUESDAY AND
CONTINUING INTO EARLY WEDNESDAY WITH THE POTENTIAL FOR
ACCUMULATING SNOW AND SLEET/ICE.
&&
.AVIATION /DISCUSSION FOR THE 020600Z TAFS/...
ISSUED AT 1130 PM EST SAT FEB 1 2014
LOWER CONFIDENCE FORECAST WITH RESPECT TO PRECIPITATION TYPES
OVERNIGHT AS LOW LEVEL COLD ADVECTION FIGHTS WITH OVERRUNNING ALONG
A FRONTAL ZONE.
APPEARS RAIN/SNOW LINE HAS BEEN PROGRESSING SLOWLY SOUTHEAST THROUGH
THE EVENING HOURS. MODELS SUGGEST A STRONGER PUSH OF WARM ADVECTION
ALOFT POSSIBLE OVER THE NEXT 4-6 HOURS ASSOCIATED WITH A WEAK
DISTURBANCE...WHICH MAY SERVE TO SLOW DOWN THE SOUTHEAST PUSH OF THE
RAIN/SNOW LINE TEMPORARILY.
BEST GUESS AT THIS TIME IS FOR THE RAIN/SNOW LINE TO BE IN THE
VICINITY OF KIND/KHUF BY ISSUANCE TIME...WITH A SLOW PUSH TOWARDS
KBMG BY 021000Z. MAY STILL BE A PERIOD OF FREEZING RAIN/SLEET
EMBEDDED WITHIN THE TRANSITION ZONE...BUT SO FAR NOT SEEING MUCH IN
THE WAY OF GROUND REPORTS AT THIS TIME. MOST OF THE PRECIPITATION
SHOULD BE OVER AROUND DAYBREAK SUNDAY.
IN GENERAL...EXPECTING IFR CEILINGS/OCCASIONAL IFR VISIBILITY
RESTRICTIONS OVERNIGHT...ESPECIALLY IN THE SNOW AREAS...WITH
CONDITIONS IMPROVING BY LATE SUNDAY MORNING AS DRIER AIR ADVECTS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR INZ030-
031-036>049-051>057-060.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...CP
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1130 PM EST SAT FEB 1 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 PM EST SAT FEB 1 2014
RAIN WILL CHANGE BACK TO A WINTRY MIX AND THEN SNOW TONIGHT AS
COLDER AIR RETURNS WITH THE PASSAGE OF A FRONTAL BOUNDARY. HIGH
PRESSURE WILL TRACK THROUGH THE REGION WITH COLD DRY WEATHER FOR THE
EARLY PART OF THE WEEK. A LARGE STORM SYSTEM WILL TRACK THROUGH THE
OHIO VALLEY TUESDAY AND WEDNESDAY...BRINGING THE POTENTIAL FOR
ACCUMULATING SNOW AND ICE. AFTER A BRIEF RESPITE...YET ANOTHER STORM
MAY BRING MORE SNOW FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1052 PM EST SAT FEB 1 2014
PRECIPITATION HAVE ALREADY CHANGED OVER TO SNOW OVER NORTHWEST
SECTIONS AND THIS CHANGEOVER WILL PROGRESS SOUTHEAST ACROSS OUR
REGION WITH MOST AREAS POSSIBLY SEEING A FEW HOURS OF LIGHT FREEZING
RAIN AND SLEET AHEAD OF THE TRANSITION TO SNOW. RAP SOUNDINGS
INDICATE SURFACE TEMPERATURES WILL FALL QUICKER THAN TEMPERATURES
ALOFT AS BUFKIT INDICATES FREEZING RAIN AT INDY MOST OF THE NIGHT.
I BELIEVE THEY ARE OVERDOING THE FREEZING RAIN AMOUNTS AND THIS WARM
LAYER ALOFT. NORMALLY YOU DO NOT GET A BIG FREEZING RAIN EVENT
ALONG A COLD FRONT. SO EVEN THOUGH LIGHT FREEZING RAIN MAY OCCUR FOR
A FEW HOURS...I EXPECT ONLY VERY LIGHT ICING AT BEST. SO WILL
CONTINUE TO COVER THIS EVENT WITH A SPECIAL WEATHER STATEMENT.
THE CHANGEOVER TO FREEZING RAIN AND SLEET MAY NOT REACH FAR SOUTHERN
SECTIONS UNTIL 500 AM. EXPECT ALL AREAS TO SEE ICE ACCUMULATIONS
WELL UNDER A TENTH OF AN INCH. SNOW ACCUMULATIONS OF 1 TO 2 INCHES
POSSIBLE ACROSS OUR NORTH. MODELS INDICATE A WEAK UPPER WAVE WILL
TRACK ACROSS OUR REGION TOWARDS 4 AM AND PRECIPITATION SHOULD
DIMINISH RAPIDLY FROM THE NORTHWEST AFTER THAT.
RAISED TEMPERATURES A DEGREE OR TWO BASED ON MODEL SURFACE
TEMPERATURES. OTHERWISE...NO OTHER CHANGES MADE AT THIS TIME.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
ISSUED AT 406 PM EST SAT FEB 1 2014
FORECAST CHALLENGES FOCUS ON POPS FOR SUNDAY AS FRONTAL BOUNDARY
SLOWLY SAGS SOUTH THROUGH THE OHIO VALLEY. IN ADDITION...A SECONDARY
WAVE WILL TRACK ALONG THE FRONT OVER THE TENNESSEE AND LOWER OHIO
VALLEYS SUNDAY NIGHT AND EARLY MONDAY. MODEL GUIDANCE CONTINUES TO
SLOWLY SHIFT THE NORTHERN EDGE OF THE MOISTURE SHIELD NORTH...WITH
SOME SUGGESTIONS THAT LIGHT SNOW MAY MANAGE TO GET NORTH OF THE OHIO
RIVER AND INTO FAR SOUTHERN INDIANA FOR A PERIOD OF TIME SUNDAY
NIGHT. WHILE THE SLOWER DEPARTURE OF THE FRONT WILL WARRANT
LINGERING POPS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SUNDAY
MORNING...WILL MAINTAIN DRY FORECAST FROM EARLY AFTERNOON SUNDAY ON
WITH DEEPER FORCING AND MOISTURE ASSOCIATED WITH THE WAVE REMAINING
ALONG AND SOUTH OF THE OHIO RIVER. ANY ADDITIONAL SHIFTS NORTH
HOWEVER WITH FUTURE MODEL RUNS WILL LIKELY REQUIRE INTRODUCING LOW
CHANCES FOR SNOW SUNDAY NIGHT OVER FAR SOUTHERN COUNTIES.
A BROAD AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST MONDAY MORNING AND SHOULD SERVE TO FINALLY PUSH THE FRONT
FURTHER SOUTH AND EAST AND AWAY FROM THE OHIO VALLEY. WITH MODEL
SOUNDINGS INDICATING PRESENCE OF SUBSIDENCE AND DRIER AIR ANTICIPATE
PLENTY OF SUNSHINE MONDAY. MID AND HIGH LEVEL CLOUD COVER WILL BEGIN
TO INCREASE FROM THE SOUTHWEST MONDAY NIGHT AS THE STORM SYSTEM THAT
WILL IMPACT THE REGION LATER ON TUESDAY INTO WEDNESDAY ORGANIZES
OVER TEXAS AND THE WESTERN GULF.
TEMPS...GENERALLY LEANED TOWARDS THE COLDER MAVMOS THROUGH THE
PERIOD WHICH MATCHED MORE CLOSELY WITH THE LOW LEVEL THERMALS. COULD
SEE QUITE THE TEMP GRADIENT NORTH TO SOUTH FOR LOWS SUNDAY
NIGHT...WITH LOWS NEAR ZERO IN THE NORTHERN WABASH VALLEY WHERE
SKIES WILL BE PARTLY CLOUDY AND THE POTENTIAL FOR A COUPLE INCHES OF
SNOW ON THE GROUND WOULD HELP TEMPS TUMBLE. CLOUD SHIELD FROM
SURFACE WAVE TRACKING TO THE SOUTH SUNDAY NIGHT WILL KEEP TEMPS UP A
BIT FROM I-70 SOUTH...POSSIBLY ONLY FALLING TO AROUND 20 IN THE
EXTREME SOUTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 257 PM EST SAT FEB 1 2014
FOCUS REMAINS POSSIBLE WINTER STORM TUESDAY INTO WEDNESDAY.
CONTINUE TO PREFER A BLEND OF GUIDANCE WITH LESS RELIANCE ON
SOMEWHAT LESS CONSISTENT GFS. GFS LOW TRACK HAS SHIFTED SLIGHTLY
SOUTHEAST AND EURO SLIGHTLY NORTHWEST...ALTHOUGH EURO REMAINS
CONSISTENTLY THE COLDER MODEL AND GFS WARMER ODDLY ENOUGH. GFS
ENSEMBLE MEMBERS REMAIN LOOSELY CLUSTERED BUT AROUND A FURTHER
SOUTHEAST TRACK THAN PREVIOUS DAYS...BUT THIS HAS YET TO TRANSLATE
TO A COLDER SOLUTION IN THE LOW LEVELS.
AS SUCH...WILL CONTINUE WITH ALL SNOW MAINLY NORTH/NORTHWEST OF
INDY...WITH A CHANCE OF SLEET/FREEZING RAIN MIXING IN A SWATH
SOUTH OF THIS...AND FREEZING RAIN/SLEET WITH A CHANCE OF SNOW
ACROSS THE FAR SOUTH LATE TUESDAY INTO TUESDAY EVENING. ALL PRECIP
AFTER 06Z WEDNESDAY LIKELY SNOW OR QUICKLY TRANSITIONING TO SNOW.
MESOSCALE FEATURES WILL BE IN PLAY AND AS SUCH AMOUNTS REMAIN VERY
DIFFICULT TO PINPOINT. BANDING WILL BE AN ISSUE WHICH COULD IMPACT
BOTH AMOUNTS AND PRECIP TYPE OWING TO DYNAMIC EFFECTS.
MESSAGE REMAINS THE SAME. CENTRAL INDIANA RESIDENTS SHOULD BE
PREPARED FOR A POSSIBLE WINTER STORM BEGINNING TUESDAY AND
CONTINUING INTO EARLY WEDNESDAY WITH THE POTENTIAL FOR
ACCUMULATING SNOW AND SLEET/ICE.
&&
.AVIATION /DISCUSSION FOR THE 020600Z TAFS/...
ISSUED AT 1130 PM EST SAT FEB 1 2014
LOWER CONFIDENCE FORECAST WITH RESPECT TO PRECIPITATION TYPES
OVERNIGHT AS LOW LEVEL COLD ADVECTION FIGHTS WITH OVERRUNNING ALONG
A FRONTAL ZONE.
APPEARS RAIN/SNOW LINE HAS BEEN PROGRESSING SLOWLY SOUTHEAST THROUGH
THE EVENING HOURS. MODELS SUGGEST A STRONGER PUSH OF WARM ADVECTION
ALOFT POSSIBLE OVER THE NEXT 4-6 HOURS ASSOCIATED WITH A WEAK
DISTURBANCE...WHICH MAY SERVE TO SLOW DOWN THE SOUTHEAST PUSH OF THE
RAIN/SNOW LINE TEMPORARILY.
BEST GUESS AT THIS TIME IS FOR THE RAIN/SNOW LINE TO BE IN THE
VICINITY OF KIND/KHUF BY ISSUANCE TIME...WITH A SLOW PUSH TOWARDS
KBMG BY 021000Z. MAY STILL BE A PERIOD OF FREEZING RAIN/SLEET
EMBEDDED WITHIN THE TRANSITION ZONE...BUT SO FAR NOT SEEING MUCH IN
THE WAY OF GROUND REPORTS AT THIS TIME. MOST OF THE PRECIPITATION
SHOULD BE OVER AROUND DAYBREAK SUNDAY.
IN GENERAL...EXPECTING IFR CEILINGS/OCCASIONAL IFR VISIBILITY
RESTRICTIONS OVERNIGHT...ESPECIALLY IN THE SNOW AREAS...WITH
CONDITIONS IMPROVING BY LATE SUNDAY MORNING AS DRIER AIR ADVECTS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...JH
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
455 AM EST SUN FEB 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 453 AM EST SUN FEB 2 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY INTO THE CNTRL CONUS. AN ELONGATED SHORTWAVE TROUGH
FROM SOUTH OF JAMES BAY TO SRN MN BOOSTING 850-700 MB RH AND
INVERSION HEIGHTS TO 5K-6K FT BROUGHT AN INCREASE IN LES ACROSS ERN
LAKE SUPERIOR. THE HEAVIEST SNOW WAS MOVING INTO NRN LUCE COUNTY
WHERE THE WAS THE GREATEST AMOUNT OF OPEN WATER UPSTREAM. FARTHER
WEST...SOME MODERATE NW FLOW LES HAD ALSO DEVELOPED OFFSHORE FROM
MARQUETTE COUNTY WHERE THERE SEEMED TO BE ENOUGH GAPS IN THE ICE
COVER SO THAT LAND BREEZES COULD SUPPORT STRONGER LOW LEVEL CONV.
THE AMOUNT OF ICE COVER OVER WRN LAKE SUPERIOR IS EXTENSIVE ENOUGH
SO THAT ONLY LIGHT SNOW HAD DEVELOPED WITH LIMITED POTENTIAL FOR ANY
ACCUMULATIONS.
TODAY...EXPECT THE NW FLOW LES TO CONTINUE THROUGH THE MORNING WITH THE
POTENTIAL FOR A FEW INCHES OF ACCUMULATION NEAR THE SHORE EAST OF
MUNISING. SNOW AMOUNTS OF AN INCH OR LESS ARE EXPECTED BETWEEN
MARQUETTE AND MUNISING. AS WINDS BACK AND INVERSION HEIGHTS DROP THIS
AFTERNOON...THE LES SHOULD DIMINISH OVER THE NW AND LIFT OFF SHORE
FROM THE NE CWA.
TONIGHT...THE BEST FORCING WITH THE NEXT CLIPPER SHORTWAVE
REMAINS WELL TO THE NORTH OVER NRN ONTARIO. SOME LES WILL BE
POSSIBLE EARLY OVER NE LUCE COUNTY BEFORE WINDS BACK TO THE SW AND
PUSH THE SNOW BANDS OFFSHORE. WITH CLEARING OVERNIGHT...TEMPS WILL
DROP TO 5 BELOW TO 10 BELOW ZERO OVER THE INLAND WEST HALF OF UPPER
MICHIGAN. HOWEVER...WITH LIGHT WINDS ONLY AROUND 5 MPH...WIND CHILLS
WILL NOT BE SIGNFICANT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN FEB 2 2014
MODELS ARE IN GOOD AGREEMENT WITH BENIGN ZONAL FLOW UNTIL WED WHEN
MODEL TO MODEL DISAGREEMENT INCREASES SIGNIFICANTLY...BUT EVEN WITH
THE VARYING SOLUTIONS NO SIGNIFICANT PRECIP IS DEPICTED OVER THE
CWA.
A SYSTEM SIMILAR TO YESTERDAY IS SHOWN MOVING S OF THE CWA TUE INTO
TUE NIGHT...BUT THAT IS NOT EXPECTED TO BRING PRECIP TO THE CWA. THE
00Z/02 NAM IS THE ONLY MODEL FAR ENOUGH N WITH THE SYSTEM TO GIVE
PRECIP CHANCES IN THE CWA...SO THAT WAS CONSIDERED AN
OUTLIER...ESPECIALLY SINCE IT IS AT THE OF THE MODEL RUN. BESIDE
THAT SYSTEM...CONFIDENCE IS VERY LOW ON ANY OTHER SIGNIFICANT
SYSTEMS TO APPROACH THE AREA. WITH LACK OF CONFIDENCE FOR WED
THROUGH SAT AND GOOD AGREEMENT /BUT LACK OF SIGNIFICANT PRECIP/ MON
THROUGH TUE NIGHT...USED A CONSENSUS OF MODEL GUIDANCE FOR THE
FORECAST. TEMPERATURES OVER THE NEXT WEEK ARE EXPECTED TO BE SIMILAR
TO THE LAST WEEK OR SO WITH HIGHS IN THE SINGLE DIGITS AND TEENS
ABOVE ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1238 AM EST SUN FEB 2 2014
LIGHT LAKE EFFECT SNOWS CONTINUE OVER THE WESTERN TAF SITES WHILE
LIGHT SNOW SHOWERS LINGER OVER KSAW. THE LES HAS BROUGHT IFR CIGS TO
KCMX AND AT TIMES HAS LOWERED VSBYS TO IFR AS WELL AS BETTER LES
BANDS MOVE OVER THAT LOCATION. VERY LIGHT SNOW AT KSAW TO END EARLY
IN THE FORECAST AS COLD FRONT PASSES THROUGH AND LIGHT DOWNSLOPE NW
WINDS INCREASE. SNOW WILL NOT RESTRICT VSBYS AT KIWD DUE TO VERY
SHORT FETCH...HOWEVER CIGS TO HOLD IN LOWER MVFR RANGE UNTIL CLOSER
TO DAYBREAK. CIGS BEGIN TO IMPROVE AROUND SUNRISE AS DRIER AIR WORKS
IN WITH INCREASING 850-500 MB Q VECTOR DIVERGENCE...WITH VFR
CONDITIONS EXPECTED THROUGH THE LATE MORNING AND AFTERNOON HOURS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 453 AM EST SUN FEB 2 2014
A RELATIVELY QUIET PERIOD OF WEATHER IS EXPECTED FOR LAKE SUPERIOR.
GALES ARE NOT EXPECTED OVER THE NEXT SEVERAL DAYS. SOME PERIODS OF
FREEZING SPRAY WILL STILL OCCUR AT TIMES OVER ANY REMAINING OPEN
WATER AREAS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...RJT
MARINE...JLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
325 AM CST SUN FEB 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST SUN FEB 2 2014
TODAY AND TONIGHT...SOME TRAPPED MOISTURE HAS DEVELOPED IN THE
PLATTE VALLEY THIS MORNING PRODUCING A 100 FT CEILING AT NORTH
PLATTE. THIS THIN VEIL OF MOISTURE...IF IT PERSISTS...SHOULD MIX OUT
AFTER SUNRISE. THE RAP HAS MISPLACED THIS MOISTURE FURTHER NORTH AND
WEST ACROSS THE CHEYENNE DIVIDE OVER THE SRN PANHANDLE. SFC OBS SHOW
THIS MOISTURE FARTHER SOUTH ACROSS NERN COLO. REGARDLESS...THE RAP
MOVES THIS MOISTURE EAST PRESUMABLY THRU SWRN NEB SOUTH OF
INTERSTATE 80. ITS POSSIBLE DENSE FOG MAY DEVELOP ALONG AND SOUTH OF
THE INTERSTATE BEFORE SUNRISE.
WIND CHILL READINGS ARE CLOSE TO -20F ACROSS THE SOUTH. IF WINDS CAN
INCREASE THEN A WIND CHILL ADVISORY WOULD BE NEEDED FOR A FEW HOURS
THIS MORNING.
OTHERWISE...THE ARCTIC HIGH CENTERED OVER THE SNOW FIELD COVERING
SWRN NEB...NRN KS AND ERN NEB IS FCST TO MOVE EAST INTO MO/IL BY
MONDAY MORNING. A WARM FRONT IS FCST TO DEVELOP ACROSS NRN NEB
TONIGHT AHEAD OF A VERY STRONG ARCTIC HIGH RIDGING FROM THE YUKON
SOUTH THROUGH THE NRN HIGH PLAINS. CLEAR SKIES ARE EXPECTED ACROSS
THE FCST AREA TODAY AND TONIGHT SUPPORTING HIGHS IN THE 20S ACROSS
THE SNOW FIELD SOUTH AND 30S ACROSS THE SNOW-FREE NORTH. THE WARM
FRONT SHOULD KEEP THE ATM WELL MIXED TONIGHT AND LOWS FOLLOW IN THE
SINGLE DIGITS SOUTH TO NEAR 10 ABOVE IN THE NORTH. THE MET GUIDANCE
SUGGESTED SUBZERO LOWS TONIGHT ACROSS THE SOUTH BUT THIS HAS BEEN
SET ASIDE FOR NOW. THE GEM REGIONAL MODEL SHOWS LOWS IN THE SINGLE
DIGITS AND THIS MODEL HAS BEEN VERIFYING THE BEST WITH THE ONGOING
TEMPERATURE FORECAST EARLY THIS MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CST SUN FEB 2 2014
12Z MONDAY AND BEYOND. THE FORECAST CONCERNS IN THE EXTENDED
PERIODS ARE BITTERLY COLD TEMPERATURES AND THE POTENTIAL FOR SNOW
LATE MONDAY THROUGH EARLY WEDNESDAY AND POSSIBLY AGAIN LATE WEEK
INTO THE WEEKEND.
MONDAY...THE MODELS ARE CONTINUING TO ADVERTISE MOISTURE RETURN IN
ADVANCE OF A SOUTHERN STREAM TROUGH ADVANCING ACROSS THE
DESERT SOUTHWEST. ISENTROPIC UPGLIDE AND OMEGA ASSOCIATED WITH A
140KT UPPER JET MAY TRIGGER SNOW PRODUCTION BY AFTERNOON...SPREADING
FROM SOUTHWEST TO NORTHEAST NEBRASKA. HOWEVER A BETTER
PRECIPITATION SIGNAL IS SHOWN EARLY ON TUESDAY AS DPVA ASSOCIATED
WITH THE SOUTHERN STREAM WAVE SPREADS EAST NORTHEAST AND EJECTS
ACROSS THE SOUTHERN PLAINS. SNOW IS EXPECTED TO BECOME WIDESPREAD
AFTER DAYLIGHT WITH THE HIGHEST CHANCES REMAINING ALONG OUR SOUTHERN
BORDERS. WILL CONTINUE TO TREND THE POP FORECAST UPWARD WITH THIS
FORECAST PACKAGE...WITH 50-60% POPS ALONG AND SOUTH OF I80 TUESDAY.
DESPITE THE INCREASE IN POPS...WILL NOT VENTURE MUCH HIGHER WITH
EXPECTED QPF AS MODEL CONSENSUS INDICATES ~0.15" ACROSS OUR
SOUTH...AND LESS THAN A TENTH OF AN INCH FOR THE NORTHERN
SANDHILLS. SNOW PRODUCTION WILL BE ABOVE CLIMO NORMS AS PROXIMITY
SOUNDINGS INDICATE A DEEP DENDRITIC GROWTH ZONE...SO DESPITE
SOMEWHAT LIMITED MOISTURE...A FEW INCHES OF SNOW MAY BE POSSIBLE
GIVEN A 15:1 /OR HIGHER/ SLR. FORCING SPREADS TO THE EAST EARLY
WEDNESDAY WITH ONLY LIGHT SNOW REMAINING...WILL LIMIT POPS TO LOW
END CHANCE DURING THE DAY. BEYOND WEDNESDAY PRECIPITATION CHANCES
BECOME LIMITED TO OUR FAR SOUTHWEST WITH THE UPPER LEVELS
TRANSITIONING TO ZONAL. THERE IS HOWEVER A BETTER PRECIPITATION
SIGNAL LATE IN THE WEEK/EARLY NEXT WEEKEND WITH THE DEVELOPMENT OF
THE NEXT WESTERN CONUS TROUGH. BOTH THE EC AND GFS...WITH SUPPORT
FROM THE ENSEMBLES SUPPORT THIS LATE WEEK SYSTEM...THUS SLIGHT
CHANCE POPS ARE WARRANTED FOR NOW.
CONCERNING TEMPERATURES...ARCTIC AIR BEHIND A STRONG COLD FRONT WILL
INFILTRATE THE REGION LATE MONDAY AND REMAIN THROUGH MUCH OF THE
EXTENDED PERIODS. TUESDAY WILL BE MUCH COLDER AS H85 TEMPERATURES
FALL TO MINUS 20 OR COLDER FOR MUCH OF THE REGION. HIGHS SHOULD TOP
OUT ONLY IN THE TEENS...WITH THE POTENTIAL OF SINGLE DIGIT HIGHS FOR
OUR NORTH. COLDER YET FOR WEDNESDAY WITH ALL LOCATIONS ACROSS THE
FORECAST AREA STRUGGLING TO REACH THE UPPER SINGLE DIGITS. HIGHS
THURSDAY AND FRIDAY WILL WARM A FEW DEGREES EACH DAY AS WEAK RETURN
FLOW TRIES TO BECOME ESTABLISHED ACROSS THE HIGH PLAINS. LOWS
WEDNESDAY...THURSDAY AND QUITE POSSIBLY FRIDAY MORNING SHOULD BE
BELOW ZERO AS THE ARCTIC HIGH SETTLES ACROSS THE HIGH PLAINS. NOTE
THAT IF ADDITIONAL FRESH SNOW WERE TO ADD TO THE SNOWPACK...THE
DETERMINISTIC GUIDANCE WOULD BE ANOMALOUSLY TOO WARM...THIS MAY BE A
CASE WHERE SOME LOCATIONS SEE THE COLDEST READINGS OF THE SEASON.
WITH THE BITTERLY COLD TEMPERATURES EXPECTED DURING THE OVERNIGHT
ANY AMOUNT OF WIND WOULD ALLOW FOR CRITICALLY LOW WIND CHILL
READINGS. WIND CHILL ADVISORIES MAY BE NEEDED WEDNESDAY AND
THURSDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1130 PM CST SAT FEB 1 2014
HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN OVER THE NEXT 24
HOURS LEADING TO CLEAR SKIES. WINDS WILL BE LIGHT AND VARIABLE
THROUGH 18Z SUNDAY. WINDS WILL BE SOUTHWESTERLY AT AROUND 10 KTS
SUNDAY AFTERNOON...BEFORE DIMINISHING TO UNDER 10 KTS SUNDAY
EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS BUFFALO NY
328 AM EST SUN FEB 2 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL PRODUCE SOME LINGERING LIGHT SNOW
TODAY ESPECIALLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES AND
CENTRAL NEW YORK. THIS WILL END BY THIS EVENING AS HIGH PRESSURE
BUILDS INTO THE REGION. HIGH PRESSURE WILL BRING MAINLY DRY
CONDITIONS MONDAY AND TUESDAY WITH SEASONABLE TEMPERATURES.
WIDESPREAD ACCUMULATING SNOW IS LIKELY TO ARRIVE TUESDAY NIGHT AND
WEDNESDAY AS LOW PRESSURE MOVES FROM THE LOWER OHIO VALLEY TO THE
MID ATLANTIC STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE ANALYSIS SHOWS A WAVY FRONTAL BOUNDARY EXTENDING FROM THE
OHIO VALLEY TO THE SAINT LAWRENCE VALLEY...WITH A WEAK WAVE OF LOW
PRESSURE HEADING INTO SOUTHEAST QUEBEC. IN THE WAKE OF THIS SURFACE
WAVE THE COLD FRONT IS MAKING HEADWAY EAST ACROSS WESTERN NY...
ALLOWING LOW LEVEL COLD ADVECTION TO BEGIN. RADAR IMAGERY SHOWING
WIDESPREAD MAINLY LIGHT PRECIP ACROSS THE ENTIRE REGION WITH AN AREA
OF BETTER RETURNS ACROSS WESTERN NY. MUCH OF THIS IS RAIN AT 08Z...
WITH FAR WESTERN NY NOW OVER TO SNOW AS COLDER AIR FILTERS BACK IN.
THE HIGHER TERRAIN OF THE TUG HILL AND WESTERN FOOTHILLS OF THE
ADIRONDACKS ARE ALSO SEEING WET SNOW.
LATEST SHORT TERM MESOSCALE MODELS SUCH AS THE NAM AND HRRR SUGGEST
THIS INITIAL WAVE OF PRECIP WILL QUICKLY DIMINISH FROM THE GENESEE
VALLEY NORTHEASTWARD THROUGH 12Z AS THE SURFACE WAVE PULLS AWAY.
THUS EXPECT THE RAIN AND HIGH ELEVATION SNOW ACROSS THE EASTERN
PORTION OF THE AREA TO MAINLY END...OR AT LEAST TAPER TO VERY LIGHT
WIDELY SCATTERED RAIN/SNOW SHOWERS. FARTHER WEST...ENOUGH
FRONTOGENESIS WILL REMAIN TO KEEP PRECIP GOING INTO THE MORNING...
ESPECIALLY ACROSS THE SOUTHERN TIER. PRECIP TYPE SHOULD BE OVER TO
ALL SNOW BY MID MORNING AS COLD AIR DEEPENS.
ANOTHER SUBTLE/WEAK BAROCLINIC WAVE MAY RIPPLE ALONG THE FRONTAL
ZONE FROM LATE MORNING THROUGH EARLY TO MID AFTERNOON. THIS IS
SUGGESTED IN THE NAM AND ESPECIALLY THE CANADIAN GEM AND HRRR MODEL
RUNS...WITH A NORTHWARD BULGE IN THE PRECIP SHIELD BRIEFLY. THIS
SEEMS REASONABLE GIVEN BOTH THE GFS AND NAM SHOW ANOTHER MID LEVEL
SHORTWAVE CROSSING THE LOWER LAKES AT THIS TIME...AND HAND 500MB
ANALYSIS VERIFIED THIS FEATURE. WITH THIS IN MIND...HAVE A BRIEF
INCREASE IN POPS AGAIN DURING THE MIDDAY HOURS ESPECIALLY ACROSS THE
SOUTHERN TIER...FINGER LAKES...AND EVENTUALLY THE SOUTHERN TUG HILL
REGION. PRECIP WILL BE ALL SNOW BY THIS TIME. BETWEEN THE LINGERING
MORNING ACTIVITY AND THE SECONDARY WAVE EXPECT LESS THAN AN INCH
ACCUMULATION IN MOST LOCATIONS...WITH 1 TO 2 INCHES FROM THE
SOUTHERN TIER INTO THE HIGHER TERRAIN OF CENTRAL NY.
AS FAR AS HEADLINES GO...WILL DROP THE ADVISORY EAST OF LAKE ONTARIO
WITH THE EXPECTATION THAT STEADIER PRECIP WILL END THERE EARLY THIS
MORNING AS THE FIRST WAVE PULLS AWAY. THE ADVISORY FOR THE SOUTHERN
TIER AND WESTERN FINGER LAKES WILL REMAIN IN PLACE THROUGH 15Z. THIS
WAS INITIALLY ISSUED DUE TO SOME REPORTS OF ICY ROADS. SURFACE
TEMPERATURES HAVE BEEN WELL ABOVE FREEZING ALL NIGHT...BUT AFTER THE
FRIGID WEATHER THE PAST FEW WEEKS PAVEMENT TEMPERATURES ARE LAGGING
BEHIND. THIS ADVISORY WILL COVER ANY LINGERING ICY SPOTS...AND THE
TRANSITION BACK TO SNOW WHICH MAY PRODUCE ADDITIONAL ICY SPOTS. IF
THE SECONDARY FRONTAL WAVE ENDS UP BEING A LITTLE MORE AGGRESSIVE
SNOWFALL WISE...THIS ADVISORY COULD BE EXTENDED A FEW HOURS TO
COVER.
TEMPERATURES WILL REMAIN FAIRLY STEADY TODAY WITH LOW LEVEL COLD
ADVECTION COUNTERACTING THE DIURNAL CYCLE. EXPECT TEMPS IN THE LOWER
30S ACROSS MOST OF THE AREA...WITH SOME LINGERING MID 30S IN CENTRAL
NY.
TONIGHT SURFACE HIGH PRESSURE WILL BUILD INTO THE CENTRAL LAKES AND
SOUTHERN ONTARIO. THIS SHOULD BRING AT LEAST SOME PARTIAL CLEARING
TO THE NORTHERN HALF OF THE REGION...WITH CLOUDS LINGERING CLOSER TO
THE PA STATE LINE WHERE ANOTHER WAVE OF LOW PRESSURE WILL RUN ALONG
THE FRONTAL ZONE AND INTO THE MID ATLANTIC STATES. COLDER AIR WILL
CONTINUE TO FILTER INTO THE REGION...WITH LOWS IN THE TEENS IN MOST
PLACES AND FEW SINGLE DIGITS ACROSS THE NORTH COUNTRY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE LOWER LAKES MONDAY...WHILE
LOW PRESSURE MOVES EAST ACROSS THE MIDDLE ATLANTIC STATES IN THE
MORNING BEFORE SLIDING OFF THE COAST DURING THE AFTERNOON. MOISTURE
ALONG THE NORTHERN FRINGES OF THIS SYSTEM...COMBINED WITH A WEAK
NORTHERLY UPSLOPE FLOW SOUTH OF LAKE ONTARIO...MAY GENERATE
SCATTERED FLURRIES ACROSS THE SOUTHERN TIER IN THE MORNING.
OTHERWISE...WE SHOULD SEE MOSTLY SUNNY SKIES AS THE HIGH BUILDS OVER
NEW YORK STATE DURING THE AFTERNOON. EXPECT MORE CLEARING MONDAY
NIGHT AND EARLY TUESDAY...THEN AN INCREASE IN CLOUDS AS THE NEXT
STORM SYSTEM TAKES SHAPE ACROSS THE NATION`S INTERIOR.
AS THE SURFACE HIGH SHIFTS EAST INTO NEW ENGLAND ON TUESDAY...LOW
PRESSURE WILL MOVE NORTH FROM THE GULF COAST STATES AND REACH THE
THE TENNESSEE VALLEY DURING THE AFTERNOON. THE PRECIPITATION
ASSOCIATED WITH THE LOW AND ITS ASSOCIATED INVERTED TROUGH WILL STAY
MAINLY SOUTH OF NEW YORK STATE...BUT CLOUDS WILL INCREASE FROM SOUTH
TO NORTH THROUGH THE DAY. AS THE LOW LIFTS NORTH TOWARD WESTERN PA
TUESDAY NIGHT...SNOW WILL SPREAD NORTH ACROSS OUR AREA FAIRLY
QUICKLY. THE GFS AND ECMWF DEPICT AN ENERGETIC WARM ADVECTION
PATTERN LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING...BUT THE
BOUNDARY LAYER WILL STAY COLD ENOUGH FOR ALL SNOW.
SUBTLE MODEL DIFFERENCES REGARDING THE PATH OF THE LOW CONTINUE TO
SHOW UP FOR WEDNESDAY. THE ECMWF MAINTAINS THE INTEGRITY OF THE
WESTERN PA LOW INTO WEDNESDAY MORNING BEFORE SHIFTING THE ENERGY TO
A LOW THAT WILL BE PASSING SOUTH OF THE SOUTHERN NEW ENGLAND COAST
DURING THE AFTERNOON. THE GFS TRANSFER THE ENERGY TO THE COASTAL LOW
SOONER. THE NAM REMAINS AN OUTLIER BY TRACKING THE MAIN CENTER OF
THE LOW MUCH FARTHER TO THE NORTH.
OVERALL...IT STILL LOOKS LIKE THE BIGGEST IMPACT FROM THIS SYSTEM IN
TERMS OF SNOWFALL WILL BE FELT ACROSS PA AND SOUTH CENTRAL NEW YORK.
HOWEVER...THE PROJECTED PATH OF THE 850 MB LOW STILL LOOKS FAVORABLE
FOR SOME ACCUMULATING SNOW ACROSS OUR ENTIRE CWA...WITH ADVISORY
TYPE ACCUMULATIONS POSSIBLE ACROSS THE SOUTHERN TIER AND UPPER
GENESEE VALLEY TUESDAY NIGHT INTO WEDNESDAY. FOR NOW...WILL CONTINUE
TO HIGHLIGHT THE POTENTIAL FOR A WIDESPREAD SNOW IN THE HWO AND WAIT
FOR LATER MODEL RUNS TO FINE TUNE THE DETAILS.
A NORTHWEST FLOW OF COLDER AIR BEHIND THE LOW WILL SET THE STAGE FOR
SOME LAKE ENHANCED SNOW SOUTHEAST OF LAKE ONTARIO WEDNESDAY
AFTERNOON. A DECREASE IN SYNOPTIC SCALE MOISTURE WILL CAUSE THE LAKE
EFFECT SNOW TO DIMINISH SOMEWHAT WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
HIGH PRESSURE BUILDS BACK ACROSS THE REGION FOR THE REMAINDER OF THE
WEEK WITH A DEEPER MID CONTINENT TROUGH DEVELOPING NEXT WEEKEND.
ASIDE FROM SOME SNOW THAT MAY LINGER EAST OF LAKE ONTARIO...EXPECT
MAINLY DRY WEATHER TO PREVAIL THURSDAY AND FRIDAY. LOW PRESSURE
MOVING EAST FROM THE OHIO VALLEY WILL BRING A CHANCE FOR LIGHT SNOW
FRIDAY NIGHT INTO SATURDAY. A CHANCE FOR SNOW WILL CONTINUE INTO
SUNDAY AS THIS LOW SETTLES OFF THE EAST COAST.
HIGH TEMPERATURES THURSDAY AND FRIDAY WILL RANGE FROM THE MID TEENS
TO LOWER 20S. SOME MODERATION IN TEMPERATURES WILL TAKE PLACE
SATURDAY. EXPECT LOWS IN THE SINGLE NUMBERS THURSDAY AND FRIDAY
NIGHTS...WITH SOME BELOW ZERO READINGS OVER THE NORTH COUNTRY
THURSDAY NIGHT.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FOR THE 06Z TAFS WIDESPREAD MVFR FLIGHT CONDITIONS ARE FOUND...WITH
POCKETS OF IFR IN SNOW. AT THE START OF THE TAF PERIOD PRECIPITATION
IS LARGELY PLAIN RAIN...WITH SNOW FALLING ACROSS THE HIGHER
ELEVATIONS OF THE TUG HILL...AND ALSO JUST TO THE WEST OF NYS ACROSS
THE NIAGARA PENINSULA. EXPECT RAIN TO QUICKLY CHANGE OVER TO SNOW IN
THE TAF CYCLE ACROSS WNY AS A COLD FRONT PUSHES EASTWARD THROUGH THE
NIGHT. SNOW WILL TAPER OFF TO SCATTERED SNOW SHOWERS JUST PAST DAWN
ACROSS FAR WNY...AND MID MORNING ACROSS THE GENESEE VALLEY AND AREAS
EAST OF LAKE ONTARIO.
BEHIND THIS COLD FRONT CIGS WILL LOWER TO IFR FOR A PERIOD OF TIME
LATE TONIGHT AND EARLY TOMORROW MORNING. THESE CIGS WILL ONLY
IMPROVE TO MVFR THROUGH THE DAY TOMORROW...WITH GENERALLY DRY
CONDITIONS AND VISIBILITIES IMPROVING BACK TO VFR. AS DRY AIR
FILTERS INTO THE EASTERN GREAT LAKES REGION CIGS SHOULD LIFT TO VFR
LATE IN THE DAY AND THROUGH THE EVENING HOURS...SAVE FOR THE
SOUTHERN TIER WHERE A NORTHWEST UPSLOPE FLOW MAY MAINTAIN MVFR CIGS
THROUGH A GOOD PORTION OF THE EVENING.
OUTLOOK...
MONDAY AND TUESDAY...VFR.
TUESDAY NIGHT AND WEDNESDAY...MVFR/IFR IN SNOW.
THURSDAY...MAINLY VFR.
&&
.MARINE...
A COLD FRONT WILL PUSH SLOWLY SOUTHEAST OF THE AREA TODAY WITH
NORTHWEST FLOW INCREASING ON LAKE ONTARIO DURING THE LATE AFTERNOON
AND EVENING. THIS WILL PRODUCE MARGINAL SMALL CRAFT ADVISORY
CONDITIONS AT THE SOUTHEAST CORNER OF THE LAKE. LATER TONIGHT HIGH
PRESSURE WILL BUILD INTO THE LOWER LAKES AND REMAIN IN PLACE MONDAY
AND TUESDAY WITH A RARE PERIOD OF LIGHT WINDS IN MID WINTER. BY
TUESDAY NIGHT AND WEDNESDAY LOW PRESSURE WILL MOVE FROM THE LOWER
OHIO VALLEY TO THE MID ATLANTIC STATES...WITH INCREASING NORTH TO
NORTHEAST WINDS ON THE LOWER LAKES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NYZ012>014-019>021-085.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EST
MONDAY FOR LOZ043-044.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...THOMAS
MARINE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1243 AM EST SUN FEB 2 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT. LOW PRESSURE TRACKING
ALONG THIS FRONT WILL PASS SOUTH OF THE AREA SUNDAY AFTERNOON AND
NIGHT. ANOTHER LOW PRESSURE SYSTEM WILL IMPACT THE REGION LATE
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
COLD FRONT IS JUST MOVING INTO THE FORECAST AREA AND WILL CONTINUE
SOUTHEAST THROUGH THE NIGHT. SHOWERS HAVE BEEN SLOWLY
OVERSPREADING THE AREA AND WILL COVER THE ENTIRE REGION BEFORE THE
NIGHT IS OVER. AS COLDER AIR BECOMES DEEPER RAIN WILL CHANGE TO
SNOW. HAVE ONCE AGAIN DELAYED THIS TRANSITION BY A FEW HOURS SO
THIS WILL MOSTLY AFFECT AREAS FROM DAYTON TO THE NORTH AND WEST
OVERNIGHT. RECENT RAP AND NAM RUNS ARE INDICATING A BAND
STRETCHING ACROSS WEST CENTRAL OHIO AND SO THERE IS SOME CONCERN
THAT MORE SUBSTANTIAL ACCUMULATIONS COULD OCCUR THERE. AT THIS
POINT FORECAST IS FOR BELOW ADVISORY AMOUNTS. BUT THIS IS
SOMETHING THAT WILL HAVE TO BE MONITORED AS THE NIGHT PROGRESSES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
PRECIPITATION WILL BE ONGOING AT THE BEGINNING OF THE PERIOD BUT
THEN RAPIDLY END DURING THE MORNING AS THE INITIAL SHORT WAVE
MOVES OFF TO THE EAST. CHANGE IN PRECIPITATION TYPE WILL CONTINUE
TO PROGRESS SOUTHEAST DURING THIS TIME FRAME. ONLY LIGHT
ADDITIONAL ACCUMULATIONS ARE EXPECTED. BUT THERE IS AT LEAST SOME
POTENTIAL FOR A PERIOD OF FREEZING RAIN DURING THE TRANSITION.
ZONAL SOUTHWEST FLOW ALOFT WILL KEEP THE MOISTURE FEED THROUGH
THE STATE OF KY INTO WV IN A SW-NE ORIENTATION...EVEN AS THE
SURFACE FRONT DIVES WELL PAST THESE STATES. THE COLD AIR
UNDERCUTTING THIS STRONG LINGERING MOISTURE FEED HAS INCREASED THE
THREAT FOR SIGNIFICANT ACCUMULATING SNOWFALL IN OUR SOUTHEASTERN
CWA. WHILE THE NAM REMAINS A VERY DRY OUTLIER...THE LATEST
EUROPEAN HELPS CONFIRM THAT DEEP MOISTURE WILL STILL BE PRESENT
DURING THE 6-12Z TIME FRAME SUN NIGHT BEFORE THE DRIER AIR WORKS
IN ON NORTH WINDS. A SMALL SHORTWAVE WITH STRONGER DYNAMICS WILL
CROSS THE SOUTHERN CWA AT H5 AROUND 12Z MONDAY AND HELP END ANY
THREAT FOR SNOWFALL IN A RAPID FASHION.
THE SURFACE HIGH OVER THE UPPER MIDWEST WILL MEANDER EAST ACROSS
THE NORTHERN OHIO VALLEY/SOUTHERN GREAT LAKES AND PROVIDE FOR A
BREAK BETWEEN SYSTEMS. EXPECT CLOUD COVER TO DROP OFF AND
TEMPERATURES TO REMAIN ON THE COOL SIDE FOR MONDAY AND MONDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MAIN FOCUS OF THE LONG TERM PERIOD WAS TO ANALYZE THE LOW
PRESSURE SYSTEM WHICH WILL AFFECT THE AREA LATE TUESDAY INTO EARLY
WEDNESDAY. HIGH PRESSURE WILL BE DEPARTING TUESDAY MORNING AS A
SOUTHERN STREAM SHORT WAVE TROUGH EJECTS FROM THE DESERT SOUTHWEST.
THIS WILL ORGANIZE A LOW PRESSURE SYSTEM OVER THE LOWER MISSISSIPPI
VALLEY WHICH WILL TRACK UP THE WESTERN SIDE OF THE APPALACHIANS
TUESDAY NIGHT. AS HAS BEEN DISCUSSED THE PAST FEW DAYS...THE TRACK
AND STRENGTH OF THIS SYSTEM WILL MEAN EVERYTHING IN TERMS OF
PRECIPITATION TYPE AND AMOUNTS IN OUR FORECAST AREA.
ITS STILL MUCH TOO EARLY TO FRET OVER EACH MODEL AND ITS RESPECTIVE
RUN AS THE TRACK OF THE LOW HAS BEEN SHIFTING ON THE ORDER OF 30-60
MILES. OF THE 12Z SOLUTIONS...THE CANADIAN CAME IN THE COLDEST...BUT
DPROG/DT ANALYSIS SUGGESTS IT HAS BEEN THE MOST ERRATIC MODEL AND IT
WAS THUSLY DISCOUNTED. OTHERWISE THE MODELS SEEM TO BE ZEROING IN ON
A TRACK PARALLEL BUT SOUTHEAST OF I-71. AN ANALYSIS OF THERMAL
PROFILES SUGGESTS MOSTLY SNOW IN OUR NORTHWESTERN COUNTIES IN WEST
CENTRAL OHIO...AND A MOSTLY RAIN IN SOUTH CENTRAL OHIO AND NORTHEAST
KENTUCKY. IN BETWEEN IS WHERE IT GETS TRICKY...AND FRANKLY ALL
PRECIPITATION TYPES WILL BE IN PLAY. PERSISTENT NORTHEASTERLY
SURFACE FLOW COMBINED WITH A WARM NOSE ALOFT MEANS THAT ICE
ACCUMULATIONS COULD BE NOTABLE IN THE TRANSITION ZONE. AS THE SREF
TRICKLES IN...IT ALSO SUPPORTS AN I-71 TRANSITION ZONE...WITH
PROBABILITIES OF ACCUMULATING SNOW DECREASING IN THIS AREA. MODEL
QPF FIELDS SUGGEST A RANGE FROM 0.6 TO 2.0 INCHES. THUS SIGNIFICANT
WINTRY ACCUMULATIONS WILL BE POSSIBLE FOR PARTS OF THE AREA AND ITS
NOT OUT OF THE QUESTION THERE COULD BE SOME MINOR FLOODING CONCERNS
IN THE SOUTH. WITH INCREASING CONFIDENCE IN THE
SITUATION...ADDITIONAL DETAILS WERE ADDED TO THE GRIDS TO REPRESENT
THE FULL MIXED BAG OF PTYPES. AT THIS TIME TEMPERATURES GENERALLY
FOLLOW THE BLEND OF RAW MODELS...WHICH CAPTURES THE BASIC
IDEA...ALTHOUGH THE GRADIENT COULD BE MUCH TIGHTER DEPENDING ON THE
LOW TRACK AND HOW MUCH WARM AIR IS PULLED NORTHWARD. THIS IS
DEFINITELY A /STAY TUNED/ TYPE OF WEATHER SYSTEM AND WILL CONTINUE
TO BE MENTIONED IN THE HWO.
ON WEDNESDAY...POPS WERE DECREASED MUCH FASTER THAN THE PREVIOUS
FORECAST AS DRIER AIR PUSHES INTO THE AREA. SOME LIGHT SNOW MAY
LINGER GENERALLY NORTH OF I-70 IN THE CYCLONIC FLOW. TEMPERATURES
WILL REMAIN STEADY OR FALL THROUGH THE DAY. THURSDAY AND FRIDAY WILL
BE TRANQUIL BUT COLD AS HIGH PRESSURE BUILDS IN. THURSDAY NIGHT WILL
BE THE COLDEST AS THE CENTER OF HIGH PRESSURE MOVES OVERHEAD. SOME
BELOW ZERO LOWS ARE SUPPORTED IN WEST CENTRAL OHIO. A RETURN OF
MOISTURE IS SHOWN FOR FRIDAY NIGHT INTO SATURDAY.
HOWEVER...OPERATIONAL AND ENSEMBLE MODEL SPREAD IS QUITE HIGH.
INTRODUCED CHANCE POPS WITH A RAIN/SNOW MIXTURE ACROSS THE
AREA...WHICH WILL BE DEPENDENT ON HOW THE SYSTEMS TRACK.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
IFR CIGS WILL GRADUALLY SPREAD ACROSS ALL TERMINALS DURING THE
EARLY MORNING AS A SURFACE COLD FRONT MOVES ACROSS THE AREA.
PRECIPITATION WILL ALSO AFFECT THE TERMINALS THROUGHOUT THE NIGHT
AND INTO THE FIRST PART OF THE DAYTIME SUNDAY. PRECIPITATION TYPE
WILL START OFF AS ALL RAIN...THEN TRANSITION TO A POSSIBLE
RAIN/SNOW MIX STARTING AT KDAY AND THEN PROGRESSIVELY
SOUTHEASTWARD DURING THE MORNING. THERE IS A CHANCE FOR FREEZING
RAIN DURING THIS TRANSITION TIME MAINLY BETWEEN KDAY AND KILN.
PRECIPITATION MAY THEN TRANSITION BRIEFLY TO SNOW BEFORE THE
PRECIPITATION SHIFTS SOUTHEAST OF OUR AREA LATER THIS MORNING.
ONCE THE PRECIPITATION IS SOUTHEAST OF OUR AREA...MVFR CONDITIONS
ARE EXPECTED THROUGH MOST OF THE DAY. ADDITIONAL PRECIPITATION MAY
BEGIN TO WORK ITS WAY BACK TOWARD KCVG/KLUK LATER IN THE DAY. AT
THIS TIME IT IS STILL UNCERTAIN HOW FAR NORTH THAT PRECIPITATION
WILL ACTUALLY OCCUR.
OUTLOOK...MVFR CEILINGS WILL LIKELY PERSIST SUNDAY NIGHT INTO
MONDAY MORNING. MVFR TO IFR CEILINGS AND VISIBILITIES LIKELY WITH
A WINTRY MIX OF PRECIPITATION LATE TUESDAY INTO WEDNESDAY MORNING.
MVFR CEILINGS AND VISIBILITIES MAY LINGER INTO WEDNESDAY NIGHT.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...
SHORT TERM...FRANKS
LONG TERM...SNYDER
AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS PORTLAND OR
930 PM PST SAT FEB 1 2014
.SYNOPSIS...A WEAK LOW PRES SYSTEM OFF THE OREGON COAST SAT
EVENING WILL MOVE SE BRUSHING ACROSS THE SOUTHERN PART OF THE
FORECAST AREA TONIGHT AND SUN. A COUPLE OF WEAK UPPER LEVEL LOWS
WILL MOVE THROUGH THE REGION SUN NIGHT THROUGH MON NIGHT AS THE
UPPER LEVEL FLOW TURNS NORTHERLY AND BRINGS COOLER AIR INTO THE
REGION. A SHOT OF COLDER CANADIAN AIR APPEARS TO BE ON THE WAY LATER
IN THE WEEK AS A COLD FRONT PUSHES IN FROM THE NE.
&&
.UPDATE....NOT MUCH CHANGE FOR TONIGHT...PRECIP MAY GRAZE THE
SOUTHERN TIER LATER TONIGHT...BUT EVEN THE HRRR WHICH IS MOST
AGGRESSIVE HAS BEEN BACKING OFF ON HOW FAR NORTH THE PRECIP WITH THE
LARGE CLOUD SHIELD OFFSHORE WILL MAKE IT.EXPECT SOME FROST AND
EVENTUALLY SOME LOW CLOUD/FOG THAT IS CURRENTLY FORMING ALONG THE
LOWER COLUMBIA NEAR KELSO.
MOST OF THE MODIFICATIONS FOR THE EVENING UPDATE WERE TO UPDATE SKY
GRIDS FOR TOMORROW AND TO EXPAND THE RAIN/SNOW SHOWER MIX WORDING FOR
SHOWER ACTIVITY MONDAY MORNING. MOST GUIDANCE SUGGESTS OVERNIGHT LOWS
EARLY MONDAY RIGHT AROUND THE FREEZING MAR...ESPECIALLY ALONG THE
NORTHERN TIER. ONSHORE LOW LEVEL FLOW WITH MODEL 850 TEMPS IN THE -6
TO -8 RANGE WOULD SUGGEST SNOW LEVELS DOWN ANYWHERE FROM JUST ABOVE
THE VALLEY FLOOR TO ABOUT 1000 FEET. SHOWER ACTIVITY LOOKS TO BE
LIGHT AND SCATTERED AS ALLUDED TO BELOW WITH WEAK MOISTURE...BUT
WOULD NOT BE SURPRISED TO SEE FLAKES MIXED IN BASED ON MOST GUIDANCE
EXCEPT THE EURO.
GFS IS SLOWER TO SPREAD THE COLDEST AIR IN THE OTHER MEDIUM TO LONG
RANGE GUIDANCE FOR THE MID=LATE WEEK COLD SNAP WHICH WILL ADD TO THE
UNCERTAINTY AS TO HOW COLD THINGS WILL BE...BUT IT WILL BE VERY COLD
NONETHELESS ESPECIALLY CONSIDERING THE WINDS...AND GIVEN THE FACT IT
HAS BEEN MILD AND THAT AVERAGE HIGHS ARE NOW ALREADY AROUND 50 FOR
THE VALLEY. THURSDAY LOOKS TO BE THE COLDEST DAY IF I HAD TO PICK ONE
RIGHT NOW. /KMD
&&
.SHORT TERM...UPPER LOW SEEN IN WATER VAPOR PICTURES WAS NEAR 41N
135W EARLY THIS AFTERNOON...SLIPPING ESE TOWARDS NORTHERN CA. A WEAK
UPPER LEVEL RIDGE ORIENTED NW TO SE HAS SET UP A SHARP DEFORMATION
ZONE ON THE N SIDE OF THE LOW...AND APPEARS LIKELY TO LIMIT ANY POPS
TONIGHT AND SUN TO THE FAR SOUTHERN BORDERS OF THE FORECAST AREA.
THE SHOWERS THAT WERE OVER SOUTHERN WA SAT AFTERNOON ARE EXPECTED TO
DISSIPATE THIS EVENING AS THE LOW LEVEL FLOW TURNS OFFSHORE.
UPPER FLOW OPENS UP FROM THE N SUN NIGHT WITH THE PASSAGE OF THE LOW
ACROSS NORTHERN CA. TH FIRST SHORTWAVE EXPECTED IN THE NORTHERLY
FLOW WAS SEEN IN SATELLITE IMAGERY OVER NORTHERN BC SAT AFTERNOON.
MODELS SHOW THIS WAVE PICKING UP LOW LEVEL MOISTURE ON ITS TREK S
DOWN THE COAST. MODEL CROSS SECTIONS INDICATE MOISTURE LIMITED BELOW
700 MB SUN NIGHT AND MON...SO WILL LIMIT POPS TO CHANCE CATEGORY
WITH BEST CHANCES ON THE COAST AND OROGRAPHICALLY FAVORED SLOPES.
WILL SEE SNOW LEVELS COME DOWN CONSIDERABLY WITH THIS FIRST SHOT OF
AIR CROSSING THE YUKON...WITH COLDER AIR SEEPING IN MON NIGHT AND
TUE WITH A COUPLE MORE SHORTWAVES FOLLOWING AND LOW LEVEL TURNING
OFFSHORE. WITH THE FOLLOWING WAVES HAVING A SLIGHTLY FURTHER E
TRAJECTORY...PREFER TO LEAN TOWARDS A DRIER SOLUTION FOR MON NIGHT
AND TUE.
.LONG TERM...ECMWF AND GFS APPEAR TO BE HONED IN ON AN UPPER AIR
PATTERN THAT DRAWS AIR DOWN FROM THE CANADIAN ARCTIC. THE MAIN
THRUST OF COLD AIR IS HEADED DOWN THE E SIDE OF THE ROCKIES...BUT
BOTH GFS AND ECMWF BREAK A TROUGH OUT TO THE W DRAWING SOME OF THE
COLD AIR TO THE W. MODELS IN RECENT RUNS HAVE PERSISTENTLY BROUGHT
H8 TEMPS ON THE ORDER OF -16 W OF THE CASCADE CREST BY THU MORNING.
WITH THE LONGWAVE TROUGH OVER THE EASTERN HALF OF CANADA IT SEEMS A
LONG WAY TO BRING THE AIR WESTWARD...BUT GIVEN THE MODEL SUPPORT IT
IS DIFFICULT TO NOT GO WITH THIS SCENARIO. THE WEAK SHORTWAVES
DROPPING DOWN EARLY IN THE WEEK ALSO HELP TO CARVE THE TROUGH
WESTWARD. THIS SCENARIO WOULD BRING THE COLDEST AIR IN SINCE EARLY
DECEMBER...BUT LIKELY DRY GIVEN THE CONTINENTAL ORIGIN.
MODELS REMAIN IN GOOD AGREEMENT GOING INTO THE WEEKEND...WHICH MAKES
FOR SOME POTENTIALLY INTERESTING WEATHER. A WARMER SYSTEM OFF THE
PACIFIC IS FORECAST TO TAP INTO SOME SUBTROPICAL MOISTURE BEFORE
MOVING INTO THE PACIFIC NW SAT. COLD AIR IN PLACE FROM LATER THIS
WEEK..AND TEMPORARILY HELD IN PLACE BY LOW LEVEL OFFSHORE FLOW COULD
MAKE FOR A MESSY TRANSITION DAY SAT AS MOISTURE OVERRUNS THE COLD
AIR BEFORE FINALLY DISPLACING IT. WITH THE MODELS IN GOOD AGREEMENT
WILL NEED TO MAKE MENTION OF WINTER PRECIPITATION POTENTIAL FOR SAT.
&&
.AVIATION...06Z TAF PACKAGE...BRIEF CLEARING AS THE REGION IS
BETWEEN SYSTEMS. MID CLOUDS ALREADY STREAMING INTO THE REGION FROM
THE CLOSED LOW HEADING SE TOWARD THE NORTHERN CALIFORNIA COAST.
THESE CLOUDS SHOULD STAY MAINLY SOUTH OF A KSLE TO KTMK LINE.
AREAS NORTH WILL HAVE A DECENT CHANGE OF FOG DEVELOPMENT UNDER
CLEARER SKIES AND LIGHT WINDS. THE PASSING CLOUDS TO THE
SOUTH WILL LIKELY INHIBIT SIGNIFICANT FOG FOR KEUG. RECENT HRRR
RUNS HAVE TRIED TO BRING SOME LIGHT RAIN AS FAR NORTH AS KPDX BUT
IT APPEARS THE MOST RECENT RUNS ARE WEAKENING AND MOST TAF
TERMINALS WILL STAY DRY. KEUG MAY SEE SOME VERY LIGHT RAIN AT TIME
THROUGH THE NIGHT BUT HAVE LOW CONFIDENCE AT BEST.
COLDER CONTINENTAL TROUGH WILL DROP SOUTH ALONG THE BC COAST LATE
DAYLIGHT HOURS SUNDAY. SPOTTY SHOWERS WILL BE ADVANCING BETWEEN
03/03Z AND 06Z AS A WEAK COLD FRONT CROSSES. BETTER CHANCES OF
PRECIP WILL BE FOR THE CASCADES AND POSSIBLY BUILDING WEST TOWARD
KEUG KTTD AND MAYBE KPDX AROUND 6Z.
KPDX AND APPROACHES...VFR TONIGHT...WITH CLEARING AT TIMES AFTER
02Z. REASONABLE TO EXPECT LOW MVFR TO IFR CIGS AFTER 08Z AS AREAS
OF FOG/LOW STRATUS FORM PRIMARILY W AND N OF KPDX. MAY BE ENOUGH
LOW LEVEL EASTERLY FLOW TO KEEP AREAS TO E OF KPDX RELATIVELY FOG
FREE OVERNIGHT. JBONK/ROCKEY.
&&
.MARINE...NO CHANGES MADE. PREVIOUS DISCUSSION FOLLOWS. WEAK PRES
GRADIENT PATTERN...WITH A WEAK LOW OVER THE PAC NW. WINDS TO
REMAIN 15 KT OR LESS THROUGH THE WEEKEND. SEAS AROUND 5 FT WILL
CONTINUE...WITH NOT MUCH CHANGE THROUGH TUE.
LOW PRES WILL APPROACH FROM THE W ON SUN...BUT WILL MOVE TO THE S
OF THE COASTAL WATERS AS IT HEADS INTO N CALIF. HIGH PRES WILL
BUILD OVER PAC NW NEXT WEEK...WITH INCREASING OFFSHORE FLOW.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
123 AM EST SUN FEB 2 2014
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AND SHIFT EAST THROUGH TONIGHT ALLOWING A
MOISTER AIRMASS INTO THE CAROLINAS AND NORTHEAST GEORGIA THROUGH THE
MIDDLE OF NEXT WEEK. AN ACTIVE WEEK IN WEATHER IS COMING WITH A
SERIES OF FRONTS CROSSING OUR REGION.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 120 AM...SATELLITE AND LATEST OBSERVATIONS INDICATED A COMPLEX
COMBINATION OF HIGH AND LOW CLOUDS ACROSS THE WESTERN CAROLINAS.
LATEST GUIDANCE SUPPORTS LINGERING CLOUD COVER THROUGH THE REST OF
THIS MORNING. I WILL UPDATE THE FORECAST TO INCREASE SKY COVER AND
WARM LOW TEMPERATURE A DEGREE OR TWO.
AS OF 945 PM...THE MAIN FCST CONCERN/CHALLENGE FOR THE EVENING
UPDATE IS THE TRENDS IN THE MVFR STRATUS...AND INCREASING SFC
DEWPTS...WHICH MAY AFFECT MIN TEMPS AND FOG DEVELOPMENT. HIGH PRES
CONTINUES TO DRIFT EAST OFF THE COAST...WHILE A COLD FRONT
APPROACHES FROM THE WEST. SWLY LLVL FLOW BETWEEN THE TWO SYSTEMS
CONTINUES TO ADVECT IN GULF MOISTURE ATOP A RESIDUAL DRY SFC-BASED
LAYER. THE 00Z FFC SNDG SHOWED A VERY SHALLOW SATURATED LAYER
BETWEEN 900-850 MB...WITH STRONG INVERSION FROM 850-800. MODELS SHOW
THE LLVL FLOW WILL VEER SLIGHTLY TO MORE WSWLY OVERNIGHT...PERHAPS
ENUF TO HAVE DOWNSLOPE AID SCATTERING OUT SOME OF THE FAIRLY THIN
STRATUS. IF THE STRATUS CLEARS IN LARGE ENUF AREAS...SOME LOCATIONS
MAY DEVELOP FOG...WHICH COULD BE DENSE. THIS IS ALREADY HAPPENING IN
SRN/CENTRAL GA. WITH THAT SAID...THE MAJORITY OF THE GUIDANCE KEEPS
ENUF MIXING AND LARGER DEWPT DEPRESSIONS SUCH THAT ANY CLEAR AREAS
WILL PROBABLY HAVE MORE LOW STRATUS FILL BACK IN RATHER THAN FOG.
THE RAP IS THE MOST BULLISH ON FOG ACRS THE GA AND SC
PIEDMONT...REACHING THE CHARLOTTE METRO AREA BY DAYBREAK. MY
THINKING IS TO LEAN TOWARD ONLY PATCHY FOG...PRIMARILY IN THE LWR
PIEDMONT SOUTH AND EAST OF I-85. HOWEVER...CONFIDENCE IS ON THE LOW
SIDE IN THIS ASPECT. THE OTHER CHANGE WITH THIS UPDATE WAS TO RAISE
MIN TEMPS UP A CATEGORY OR SO IN SPOTS...GIVEN THE LARGE INCREASE IN
DEWPTS...AND THE EXPECTED CLOUD COVER OVERNIGHT.
PREVIOUS DISCUSSION...
TONIGHT AND TOMORROW...MOISTURE PLUME ASSOCIATED WITH ISENTROPIC
ASCENT WILL PUSH OFF TO THE EAST OVERNIGHT LEADING TO DECREASING
POPS. LINGERING MOISTURE IN THE BOUNDARY LAYER WILL LIKELY ALLOW
FOR LOW CLOUDS TO PERSIST THROUGH THE OVERNIGHT HOURS BEFORE BURNING
OFF AROUND DAYBREAK SUNDAY. TEMPERATURES OVERNIGHT WILL ACTUALLY
REMAIN QUITE MILD AND ABOVE NORMAL AS DENSE SKY COVER INSULATES FROM
RADIATIONAL COOLING ACROSS MOST OF THE NC/SC PIEDMONT WITH COOLER
TEMPERATURES ACROSS THE MOUNTAIN VALLEYS. THE HIGHER ELEVATIONS
WILL LIKELY BE WARMER THAN VALLEY LOCATIONS DUE TO SOUTHWESTERLY
WARM ADVECTION ALOFT...THUS SOME PATCHY FOG IS POSSIBLE IN THE
VALLEY AREAS AS TEMPERATURES FALL OFF AND APPROACH SATURATION. WITH
THAT SAID...CONFIDENCE IS NOT SUBSTANTIALLY HIGH IN THAT REGARD AS
DEWPOINTS REMAIN VERY LOW. SUNDAY LOOKS TO BE A FAIRLY NICE DAY
ACROSS MOST THE REGION AS THE COLD FRONT APPROACHES FROM THE WEST.
POPS WILL RAMP BACK UP TO SOLID CHANCE LEVELS ACROSS THE WESTERN
MOUNTAIN ZONES AS THE FRONT APPROACHES. AS FOR THE
FOOTHILLS/PIEDMONT...EXPECT ABOVE NORMAL TEMPERATURES AMIDST PARTLY
TO MOSTLY CLOUDY SKIES WITH LIGHT/MODERATE SOUTHWEST WINDS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AS OF 155 PM SATURDAY...WITH THE UPPER AIR PATTERN CHANGE WILL COME
A TRANSITION TO A WET/UNSETTLED REGIME ACROSS THE SOUTHEAST AND
MID-ATLANTIC DURING THE UPCOMING WEEK. SOUTHERN STREAM SHORT WAVE
TROUGH EJECTING FROM THE SOUTHERN PLAINS LATE MONDAY WILL INITIATE
LOW-LEVEL CYCLOGENESIS ACROSS THE TENN VALLEY BY EARLY MONDAY...
WITH SURFACE LOW LIFTING NORTHEAST ACROSS THE LEE OF THE
APPALACHIANS. THIS WILL ACT TO MAXIMIZE LOW-LEVEL ISENTROPIC LIFT
AND FRONTOGENESIS ACROSS WESTERN NC AND EAST TENN BY LATE SUNDAY
NIGHT. PRECIP SHIELD WILL MOVE GENERALLY ALONG AND NORTH OF THE
SURFACE LOW...WHERE QPF OF 1 TO 2 INCHES CAN BE EXPECTED...MAINLY
ALONG AND WEST OF THE BLUE RIDGE. MAX AMOUNTS WILL LIKELY OCCUR
ACROSS SOUTHWEST NC...WHERE STRONG SW FLOW WILL RESULT IN UPSLOPE
LIFT...AUGMENTING THE SYNOPTIC FORCING. ELSEWHERE...QPF SHOULD
GENERALLY RANGE FROM .5-1 INCH ACROSS THE FOOTHILLS TO .25-.5 INCH
ACROSS SOUTHERN PIEDMONT AREAS. WINTRY PRECIP CONTINUES TO APPEAR
LIKE A VERY LOW PROBABILITY EVENT...EVEN ACROSS THE NORTHERN NC
MTNS...WHERE OPERATIONAL MODEL SOUNDINGS ARE ALL SOLIDLY IN THE RAIN
SPECTRUM. EVEN ENSEMBLE GUIDANCE IS STRONGLY SUPPORTIVE OF AN
ALL-RAIN EVENT ACROSS THE NRN MTNS.
FORCING WILL SHIFT RAPIDLY NE OF THE AREA BY MONDAY AFTERNOON...
BRINGING AN END TO WIDESPREAD RAIN. HOWEVER...AS SURFACE LOW SHIFTS
OFF THE MID-ATLANTIC COAST...1030+ MB SURFACE HIGH WILL BE OOZING
ACROSS THE OHIO VALLEY/LOWER GREAT LAKES...SPILLING COLD AIR DOWN
THE EASTERN SEABOARD AND SIGNALING THE ONSET OF A PERIOD OF
CLASSICAL COLD AIR DAMMING ACROSS THE SOUTHEAST/MID-ATLANTIC BY LATE
MONDAY NIGHT. AS ANOTHER...STRONGER SHORT WAVE BEGINS TO LIFT OUT OF
THE SOUTHERN PLAINS BY TUE MORNING...UPGLIDE WILL INCREASE ABOVE
COLD AIR WEDGE ACROSS OUR AREA...RESULTING IN LIGHT PRECIP
DEVELOPMENT. A CONSENSUS OF FORECAST SOUNDINGS FROM THE NAM...
SREF...AND GFS SUGGESTS A RATHER HIGH POTENTIAL OF -FZRA IN THE
CLIMATOLOGICALLY FAVORED AREAS OF THE EASTERN BLUE RIDGE (NORTH OF
I-40) WITHIN CLASSIC CAD REGIME EARLY TUE...AND WE WILL CONTINUE A
MENTION OF SEVERAL HOURS OF -FZRA OR -RA/-FZRA. FORTUNATELY...
GUIDANCE ALSO SEEMS TO HAVE ARRIVED AT A CONSENSUS THAT THE PARENT
HIGH WILL BE TRANSIENT...AND THAT CAD MAY BE IN A WEAKENING PHASE BY
TUE AFTERNOON...WHEN PRECIP RATES WOULD BEGIN TO INCREASE.
THEREFORE...WHILE A BRIEF PERIOD OF LIGHT ICE ACCUMULATION APPEARS
LIKELY...ICE STORM CONDITIONS CONTINUE TO LOOK UNLIKELY ATTM.
AS SURFACE LOW LIFTS RAPIDLY NORTHEAST ON THE WEST SIDE OF THE
APPALACHIANS...CAD EROSION SHOULD GRADUALLY OCCUR TUE NIGHT INTO
EARLY WED... RESULTING IN DIMINISHING UPGLIDE PRECIP AHEAD OF
ADVANCING COLD FRONTAL BAND. WITH WEAKENING FORCING ALONG THE
FRONTAL ZONE...MODEL GUIDANCE DEPICTS A DIMINISHING BAND OF PRECIP
ALONG THE FRONT AS IT TRAVERSES THE AREA EARLY WED. HOWEVER...IT IS
LIKELY THAT SOME DESTABILIZATION WILL OCCUR IN THE WARM SECTOR BY
WED AFTERNOON...WITH THE PRECIP BAND LIKELY BECOMING REINVIGORATED
AS IT INTERACTS WITH THIS UNSTABLE AIR. IF THE COLD FRONT PROVES TO
MOVE MORE SLOWLY THAN CURRENT GUIDANCE SUGGESTS...THUNDERSTORMS WILL
BE POSSIBLE ACROSS THE PIEDMONT WED AFTERNOON... BUT CONFIDENCE IS
STILL TOO LOW TO FORECAST TS OCCURRENCE ATTM.
TEMPS WILL GENERALLY BE MUCH ABOVE NORMAL THROUGH THE PERIOD...WITH
THE WARM TREND INTERRUPTED BY VERY COOL CONDITIONS (TEMPS AT LEAST
10 DEGREES BELOW CLIMO) WITHIN THE CAD REGIME LATE MON NIGHT THROUGH
TUE EVENING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
AS OF 225 PM EST SAT...GOOD MODEL AGREEMENT IS HAD IN THE FIRST
PORTION OF THE FCST. THE NW FLOW SN SHOULD BE TAPERING OFF RATHER
QUICKLY WED NIGHT AS DRYING OCCURS IN THE H92/H85 LAYER ON THE FRONT
END OF A DRY AND COLD ARCTIC AIRMASS. THERE SHOULDN/T BE TOO MUCH OF
A SE/RN PUSH WITH THE ARCTIC FRONT OUTSIDE THE MTNS THU AS THE MEAN
MLVL FLOW REMAINS SW/LY. THIS SHOULD CREATE A DISPARATE MAX
TEMPERATURE REGIME ACROSS THE FA WITH THE MTN VALLEYS WARMING ABOUT
5-8 DEGREES LESS THAN THE NON/MTNS. OVERALL...MAX TEMPS SHOULD BE
HELD ABOUT 8-12 DEGREES BELOW NORMAL IN GOOD INSOLATION YET COLD
N/LY SFC FLOW.
UNCERTAINTY INCREASES IN THE FCST BEGINNING THU EVENING THROUGH THE
PERIOD. THE 00Z GFS IS STILL A COLDER AND MORE DYNAMIC OUTLIER THAN
THE CWM/ECMWF SOLNS AND THE MODEL HAS A VERY DIFFERENT ULVL
CONFLUENT PATTERN OVER THE NE CONUS. THE GFS IS PRODUCING A MUCH
STRONGER AND COLDER SFC HIGH THAN THE OTHER OP MODELS AS IT/S
UPPER PATTERN INCLUDES AN UPSTREAM RIDGE BEHIND THE CONFLUENT ZONE.
THE OTHER MODELS HAVE CYCLONIC FLOW IN THIS AREA...THUS THE GFS IS
ABLE TO SUSTAIN STRONGER LLVL SUPPORT.
A QUICK LOOK AT THE INCOMING 12Z ECMWF SHOWS THIS MODEL IS TRENDING
TOWARD THE UPPER PATTERN OF THE GFS...BUT IT STILL HAS A WEAKER SFC
LOW...ALBEIT IN A BETTER CAD POSITION BY 12Z FRI. SOUNDINGS ON THE
GFS ARE SO COLD WITH THE CAD ONSET THAT THEY SHOW ALL SNOW FOR THE
FIRST PART OF FRI CHANGING OVER THE -FZRA IN THE AFTERNOON ACROSS
THE NRN ZONES. THE OLD ECMWF HAD ALL RAIN...WHILE THE NEW ECMWF
SOUNDINGS ARE MUCH COLDER THROUGH H7. WITH SO MUCH CHANGE OCCURRING
IN THE MODELS AND VARYING AVAILABLE MOISTURE DIFFERENCES ASSOCIATED
WITH SFC CYCLOGENESIS...POPS HAVE BEEN LEFT IN THE CHANCE RANGE
WITH A PUSH TOWARD THE HIGHER END. WILL STILL COUNT ON A STRONG WARM
NOSE BUILDING IN FRI AND MAKING THE CASE FOR -FZRA AS THE STRONGER
CAD SCENARIO LOOKS TO BE FAVORED ATTM. IT/S TOO EARLY TO SPECULATE ON
QPF/ICE AMOUNTS AS THE LLVL MASS FIELDS/FLUXES HAVE LOW CONFIDENCE
AND NEED TO BE FIGURED OUT...BUT THIS WILL BE A SYSTEM TO KEEP AN
EYE ON FRI INTO SAT.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
AT KCLT...THE 0Z NAM12 INDICATES THAT A BAND OF LESS THAN 5 MB SFC
CONDENSATION PRESSURE DEFICITS WILL REMAIN ACROSS THE EASTERN
PIEDMONT THROUGH DAYBREAK. FOLLOWING THE OBS TRENDS AND BLEND OF
PREFERRED GUIDANCE...I WILL KEEP MVFR CEILINGS THROUGH THE REST OF
THE PRE DAWN PERIOD. IFR CEILINGS MAY DEVELOP ACROSS THE TERMINAL
BETWEEN 11Z-16Z. VFR CONDITIONS SHOULD RETURN BY MIDDAY AS THE
COASTAL LOW TRACKS NORTHEAST. LOW PRESSURE DEVELOPING OVER THE
SOUTHERN MISSISSIPPI RIVER VALLEY THIS AFTERNOON IS EXPECTED TO LIFT
ACROSS THE PIEDMONT TONIGHT. LIFT AND MOISTURE ASSOCIATED WITH THE
LOW SHOULD RESULT IN AREAS OF RAIN ACROSS THE REGION AFTER 3Z. WINDS
SHOULD REMAIN SOUTH AND SOUTHWEST THROUGH THE PERIOD...SPEEDS
BETWEEN 5 TO 10 MPH.
ELSEWHERE...VFR CONDITIONS ARE EXPECTED TO LINGER ACROSS
KAVL...KGSP...KGMU AND KHKY THROUGH SUNRISE. HOWEVER...A PERIOD OF
MVFR CEILINGS MAY DEVELOP DURING THE MID MORNING. KAND WILL LIKELY
OBSERVE MVFR CEILINGS THROUGH MOST OF THE DAYLIGHT HOURS. LOW
PRESSURE DEVELOPING OVER THE SOUTHERN MISSISSIPPI RIVER VALLEY THIS
AFTERNOON IS EXPECTED TO LIFT ACROSS THE REGION TONIGHT. LIFT AND
MOISTURE ASSOCIATED WITH THE LOW SHOULD RESULT IN AREAS OF RAIN
ACROSS THE REGION AFTER 3Z. WINDS SHOULD REMAIN SOUTH AND SOUTHWEST
THROUGH THE PERIOD...SPEEDS BETWEEN 5 TO 10 MPH.
OUTLOOK...A COLD FRONT WILL ENTER THE AREA SUNDAY NIGHT...PRODUCING
SHOWERS AND RESTRICTIONS...WHICH WILL CONTINUE INTO MONDAY.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 84% HIGH 88% HIGH 100% HIGH 91%
KGSP HIGH 93% HIGH 83% HIGH 95% HIGH 94%
KAVL HIGH 100% HIGH 100% HIGH 88% HIGH 91%
KHKY HIGH 99% HIGH 100% HIGH 100% HIGH 94%
KGMU HIGH 95% MED 79% HIGH 92% HIGH 91%
KAND HIGH 88% HIGH 93% HIGH 96% HIGH 94%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...NED
SHORT TERM...JDL
LONG TERM...SBK
AVIATION...NED
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1150 PM CST SAT FEB 1 2014
.UPDATE...
UPDATED FOR THE 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1035 PM CST SAT FEB 1 2014/
UPDATE...
UPDATED TO ADD PATCHY FOG.
DISCUSSION...
COLD FRONT NOW NEAR JONESBORO ARKANSAS WILL CONTINUE TO SURGE
SOUTHEAST OVERNIGHT. PATCHY FOG...DENSE AT TIMES HAS ACCOMPANIED
THE BOUNDARY IN ADDITION TO AN INCREASE IN RAIN ACTIVITY. HAVE
ADDED THE FOG MENTION IN THE FORECAST FOR TONIGHT AND TOMORROW. A
DENSE FOG ADVISORY IS NOT ANTICIPATED ATT...AS GUSTY NORTH WINDS WILL
DEVELOP A FEW HOURS AFTER FRONTAL PASSAGE KEEPING VISIBILTIES HIGHER.
CONCERNING WINTER WEATHER FOR THE SOUTH...THE LATEST NAM AND GFS MODEL
ARE INDICATING SOME TEMPERATURE DISPARITIES FOR TOMORROW
EVENING`S PRECIPITATION TYPE ACROSS THE I-40 CORRIDOR. THE NAM IS NOW
COLDER... SHOWING A CHANGEOVER FROM RAIN TO FREEZING RAIN AND THEN
SLEET LATER IN THE EVENING. WHERE AS THE GFS KEEPS THE REGION
RIGHT AT 33F THROUGH NEARLY THE END OF PRECIPITATION EVENT. LATER
FORECASTS AND TRENDS FROM THE EURO AND HRRR MODELS MAY INDICATE THE
NEED FOR THE MIDNIGHT CREW...OR EVEN THE SUNDAY DAY CREW TO
EXTENT THE CURRENT ADVISORY SOUTH.
JAB
&&
.PREV DISCUSSION... /ISSUED 425 PM CST SAT FEB 1 2014/
.CURRENTLY...A SURFACE LOW PRESSURE SYSTEM SITS OVER CENTRAL
ILLINOIS WITH AN ASSOCIATED COLD FRONT DRAPED FROM CENTRAL
ILLINOIS...DOWN THROUGH SOUTHERN ILLINOIS AND SOUTHEASTERN
MISSOURI...AND BACK THROUGH WESTERN ARKANSAS INTO OKLAHOMA. ALONG
THE FRONT...RAIN CAN BE FOUND OUT AHEAD OF IT WITH VARIOUS TYPES OF
WINTRY PRECIPITATION FOUND ON THE BACKSIDE. RAIN HAS FINALLY
OVERSPREAD INTO NORTHEAST ARKANSAS AS OF 3 PM. THIS FRONT WILL
CONTINUE TO BE THE FOCUS FOR VARIOUS TYPES OF WEATHER OVER THE
NEXT 24 HOURS.
.SHORT TERM...TONIGHT THROUGH TUESDAY...
A TRICKY FORECAST OVER THE NEXT 72 HOURS OR SO. A COLD FRONT THAT
IS CURRENTLY LOCATED TO OUR IMMEDIATE AND NORTH AND WEST WILL PUSH
THROUGH OVERNIGHT TONIGHT. WIDESPREAD SHOWERS WILL ACCOMPANY THE
FRONT. TEMPERATURES WILL SWIFTLY DROP ACCORDINGLY BY TOMORROW
MORNING WITH WIDESPREAD 30S IN NORTHEAST ARKANSAS AND WEST
TENNESSEE WITH 40S TO OUR SOUTH. A BRIEF CHANCE OF RAIN CHANGING OVER
TO FREEZING RAIN WILL EXIST IN FAR NORTHEAST ARKANSAS AND THE
MISSOURI BOOTHEEL. NO ACCUMULATION IS EXPECTED DUE TO THE
RELATIVELY WARM AS WELL AS WET GROUND.
TEMPERATURES WILL CONTINUE TO COOL DURING THE DAY ON SUNDAY AS
PRECIPITATION CONTINUES TO FALL. FAR NORTHEAST ARKANSAS AND NORTHWEST
TENNESSEE WILL LIKELY REMAIN AROUND OR BELOW THE FREEZING MARK.
THIS WILL ALLOW PRECIPITATION TO FALL EITHER AS FREEZING RAIN IN
THE MORNING HOURS AND EVENTUALLY CHANGING OVER TO SLEET BY LATE
MORNING. SOUTH OF THE I-40 CORRIDOR MOSTLY RAIN IS EXPECTED UNTIL
AFTER SUNDOWN.
MODEL GUIDANCE IS IN GOOD AGREEMENT ON TEMPERATURES REMAINING COLD
ENOUGH TO SUPPORT FROZEN PRECIPITATION ACROSS THE MAJORITY OF OUR
FORECAST AREA. SNOW ACCUMULATIONS ARE GOING TO BE PREDOMINANTLY
NORTH OF THE I-40 CORRIDOR. BY ABOUT NOON TOMORROW...SLEET WILL
BEGIN TO FALL ACROSS FAR NORTHEAST ARKANSAS...THE MISSOURI
BOOTHEEL...AND NORTHWEST TENNESSEE. AS SUB-FREEZING AIR CONTINUES
TO MOVE SOUTHEASTWARD...SLEET WILL TRANSITION OVER TO SNOW AFTER
ABOUT 3 PM IN THE AFOREMENTIONED REGION. THE SNOW IS EXPECTED TO
CONTINUE THROUGH ABOUT MIDNIGHT IN THAT REGION. ACCUMULATIONS
RIGHT NOW ARE EXPECTED TO REMAIN JUST BELOW WARNING CRITERIA WITH
APPROXIMATELY 1 TO 3 INCHES EXPECTED FROM THE I-40 CORRIDOR NORTH
TO THE FORECAST AREA BORDER. THEREFORE A WINTER WEATHER ADVISORY
HAS BEEN ISSUED FOR COUNTIES NORTH OF THE I-40 CORRIDOR IN BOTH
EASTERN ARKANSAS AND WEST TENNESSEE.
AFTER MIDNIGHT THE WINTER PRECIPITATION IS EXPECTED TO MOVE
FARTHER SOUTH INTO NORTH MISSISSIPPI AND EVENTUALLY INTO THE
TUPELO AREA. SINCE ANY MOISTURE WILL BE SHORT-LIVED BY THE TIME
COLD AIR MAKES ITS WAY DOWN TO NORTH MISSISSIPPI...NO SNOW OR
SLEET ACCUMULATION IS EXPECTED. SOME FLURRIES WILL BE POSSIBLE IN
THE MORNING AS THE SYSTEM EXITS THE REGION MONDAY MORNING.
MONDAY MORNING WILL BE QUITE COLD AND ANY ACCUMULATIONS WILL
LIKELY STILL BE ON THE ROADS. FOR THIS...A SPECIAL WEATHER
STATEMENT HAS BEEN ISSUED FOR THE AREA AS WELL AS THE HAZARDOUS
WEATHER OUTLOOK UPDATED. ROADS WILL LIKELY BE SLICK.
ON MONDAY AFTERNOON A BRIEF WARMUP IS EXPECTED WITH HIGHS
PREDOMINANTLY IN THE 40S WITH SOME 30S IN NORTHEAST ARKANSAS. SOME
SNOW MAY STILL BE ON THE GROUND THOUGH. ANOTHER FAST MOVING SYSTEM
IS EXPECTED TO BRING RAIN TO THE ENTIRE MID-SOUTH BY LATE MONDAY
NIGHT INTO TUESDAY AFTERNOON. AS THE RAIN OVERSPREADS THE COLD AIR
IN NORTHEAST ARKANSAS AND FAR NORTHWEST TENNESSEE...A CHANCE OF
FREEZING RAIN WILL BE POSSIBLE. FOR NOW THERE MAY BE SOME
ACCUMULATIONS ON ELEVATED SURFACES. WILL CONTINUE TO MONITOR THE
SITUATION THIS SYSTEM IS EXPECTED TO MOVE QUICKLY AND FREEZING
RAIN WILL CHANGE OVER TO RAIN BY TUESDAY AFTERNOON.
.LONG TERM...WEDNESDAY WILL ONLY SEE HIGHS IN THE 30S AS COLD AIR
FUNNELS IN BEHIND THE SYSTEM. WEDNESDAY AND THURSDAY WILL BE DRY
AND COLD BEFORE ANOTHER SYSTEM MOVES INTO THE FORECAST AREA BY
FRIDAY MORNING. THIS SYSTEM WILL BRING ANOTHER ROUND OF WINTER
WEATHER TO THE MID-SOUTH. THIS SYSTEM RIGHT NOW APPEARS TO BE MUCH
STRONGER THAN THE ONE WE WILL SEE TOMORROW NIGHT.
AC3
&&
.AVIATION...
06Z TAF CYCLE
A COLD FRONT POSITIONED BETWEEN KJBR AND KMEM/KMKL WILL CONTINUE
TO MOVE SOUTH OVERNIGHT.
IFR CIGS HAVE DEVELOPED AT KJBR AND SHOULD PERSIST INTO SUNDAY
AFTERNOON. WINDS HAVE ALSO GONE NORTH AND WILL PICK UP IN SPEED
AND BECOME GUSTY AT TIMES. RAIN WILL CONTINUE THROUGH EARLY SUNDAY
MORNING BEFORE TRANSITIONING TO A RAIN/SLEET MIX THROUGH MID
MORNING...THEN TO FREEZING RAIN/SLEET MIX FROM LATE MORNING
THROUGH EARLY AFTERNOON...THEN TO ALL SNOW SUNDAY AFTERNOON AND
EVENING. VSBYS WILL BE REDUCED TO 1/2SM AT TIMES IN MODERATE SNOW
DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. SNOW WILL LET
UP IN INTENSITY BY LATE EVENING WITH IMPROVING VSBYS BUT CONTINUED
IFR CIGS.
THE FRONT SHOULD PASS THROUGH KMEM AND KMKL OVER THE NEXT FEW
HOURS WITH WINDS TURNING NORTHERLY AND INCREASING IN INTENSITY
LATER TONIGHT. CIGS WILL ALSO DROP FROM VFR TO IFR WITH RAIN
BECOMING WIDESPREAD. A FEW RUMBLES OF THUNDER MAY ALSO OCCUR AS
ELEVATED INSTABILITY WAS NOTED FROM 00Z LZK SOUNDING. A TRANSITION
TO FREEZING RAIN WILL BE POSSIBLE BETWEEN 01Z-03Z MONDAY AND
PERSIST THROUGH THE END OF THE TAF PERIOD WITH CONTINUED IFR CIGS.
KTUP SHOULD SEE CIGS LOWER TO IFR AFTER 09Z AS LOW LEVEL STRATUS
IN SOUTHERLY FLOW ADVECTS NORTHWARD. THE FRONT SHOULD PUSH SOUTH
OF KTUP AFTER SUNRISE WITH RAIN BECOMING WIDESPREAD. IFR CIGS
SHOULD DEVELOP AND PERSIST THROUGH SUNDAY AND SUNDAY NIGHT.
MODERATE RAIN WILL ALSO BE POSSIBLE SUNDAY AFTERNOON AND EVENING
ALONG WITH STRONG AND GUSTY NORTH WINDS.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 36 38 28 42 / 90 90 80 10
MKL 35 37 28 42 / 90 90 80 10
JBR 32 32 25 36 / 70 80 80 10
TUP 49 49 32 46 / 40 90 80 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR CLAY-CRAIGHEAD-GREENE-LAWRENCE-MISSISSIPPI-
POINSETT-RANDOLPH.
MO...WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR DUNKLIN-PEMISCOT.
MS...NONE.
TN...WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR DYER-LAKE-LAUDERDALE-OBION-TIPTON.
WINTER WEATHER ADVISORY FROM NOON SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR CARROLL-CROCKETT-DECATUR-GIBSON-HAYWOOD-HENDERSON-
HENRY-MADISON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1035 PM CST SAT FEB 1 2014
.UPDATE...
UPDATED TO ADD PATCHY FOG.
&&
.DISCUSSION...
COLD FRONT NOW NEAR JONESBORO ARKANSAS WILL CONTINUE TO SURGE
SOUTHEAST OVERNIGHT. PATCHY FOG...DENSE AT TIMES HAS ACCOMPANIED
THE BOUNDARY IN ADDITION TO AN INCREASE IN RAIN ACTIVITY. HAVE
ADDED THE FOG MENTION IN THE FORECAST FOR TONIGHT AND TOMORROW. A
DENSE FOG ADVISORY IS NOT ANTICIPATED ATT...AS GUSTY NORTH WINDS WILL
DEVELOP A FEW HOURS AFTER FRONTAL PASSAGE KEEPING VISIBILTIES HIGHER.
CONCERNING WINTER WEATHER FOR THE SOUTH...THE LATEST NAM AND GFS MODEL
ARE INDICATING SOME TEMPERATURE DISPARITIES FOR TOMORROW
EVENING`S PRECIPITATION TYPE ACROSS THE I-40 CORRIDOR. THE NAM IS NOW
COLDER... SHOWING A CHANGEOVER FROM RAIN TO FREEZING RAIN AND THEN
SLEET LATER IN THE EVENING. WHERE AS THE GFS KEEPS THE REGION
RIGHT AT 33F THROUGH NEARLY THE END OF PRECIPITATION EVENT. LATER
FORECASTS AND TRENDS FROM THE EURO AND HRRR MODELS MAY INDICATE THE
NEED FOR THE MIDNIGHT CREW...OR EVEN THE SUNDAY DAY CREW TO
EXTENT THE CURRENT ADVISORY SOUTH.
JAB
&&
.PREV DISCUSSION... /ISSUED 616 PM CST SAT FEB 1 2014/
UPDATE...
UPDATED FOR THE 00Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 425 PM CST SAT FEB 1 2014/
CURRENTLY...A SURFACE LOW PRESSURE SYSTEM SITS OVER CENTRAL
ILLINOIS WITH AN ASSOCIATED COLD FRONT DRAPED FROM CENTRAL
ILLINOIS...DOWN THROUGH SOUTHERN ILLINOIS AND SOUTHEASTERN
MISSOURI...AND BACK THROUGH WESTERN ARKANSAS INTO OKLAHOMA. ALONG
THE FRONT...RAIN CAN BE FOUND OUT AHEAD OF IT WITH VARIOUS TYPES OF
WINTRY PRECIPITATION FOUND ON THE BACKSIDE. RAIN HAS FINALLY
OVERSPREAD INTO NORTHEAST ARKANSAS AS OF 3 PM. THIS FRONT WILL
CONTINUE TO BE THE FOCUS FOR VARIOUS TYPES OF WEATHER OVER THE
NEXT 24 HOURS.
SHORT TERM...TONIGHT THROUGH TUESDAY...
A TRICKY FORECAST OVER THE NEXT 72 HOURS OR SO. A COLD FRONT THAT
IS CURRENTLY LOCATED TO OUR IMMEDIATE AND NORTH AND WEST WILL PUSH
THROUGH OVERNIGHT TONIGHT. WIDESPREAD SHOWERS WILL ACCOMPANY THE
FRONT. TEMPERATURES WILL SWIFTLY DROP ACCORDINGLY BY TOMORROW
MORNING WITH WIDESPREAD 30S IN NORTHEAST ARKANSAS AND WEST
TENNESSEE WITH 40S TO OUR SOUTH. A BRIEF CHANCE OF RAIN CHANGING OVER
TO FREEZING RAIN WILL EXIST IN FAR NORTHEAST ARKANSAS AND THE
MISSOURI BOOTHEEL. NO ACCUMULATION IS EXPECTED DUE TO THE
RELATIVELY WARM AS WELL AS WET GROUND.
TEMPERATURES WILL CONTINUE TO COOL DURING THE DAY ON SUNDAY AS
PRECIPITATION CONTINUES TO FALL. FAR NORTHEAST ARKANSAS AND NORTHWEST
TENNESSEE WILL LIKELY REMAIN AROUND OR BELOW THE FREEZING MARK.
THIS WILL ALLOW PRECIPITATION TO FALL EITHER AS FREEZING RAIN IN
THE MORNING HOURS AND EVENTUALLY CHANGING OVER TO SLEET BY LATE
MORNING. SOUTH OF THE I-40 CORRIDOR MOSTLY RAIN IS EXPECTED UNTIL
AFTER SUNDOWN.
MODEL GUIDANCE IS IN GOOD AGREEMENT ON TEMPERATURES REMAINING COLD
ENOUGH TO SUPPORT FROZEN PRECIPITATION ACROSS THE MAJORITY OF OUR
FORECAST AREA. SNOW ACCUMULATIONS ARE GOING TO BE PREDOMINANTLY
NORTH OF THE I-40 CORRIDOR. BY ABOUT NOON TOMORROW...SLEET WILL
BEGIN TO FALL ACROSS FAR NORTHEAST ARKANSAS...THE MISSOURI
BOOTHEEL...AND NORTHWEST TENNESSEE. AS SUB-FREEZING AIR CONTINUES
TO MOVE SOUTHEASTWARD...SLEET WILL TRANSITION OVER TO SNOW AFTER
ABOUT 3 PM IN THE AFOREMENTIONED REGION. THE SNOW IS EXPECTED TO
CONTINUE THROUGH ABOUT MIDNIGHT IN THAT REGION. ACCUMULATIONS
RIGHT NOW ARE EXPECTED TO REMAIN JUST BELOW WARNING CRITERIA WITH
APPROXIMATELY 1 TO 3 INCHES EXPECTED FROM THE I-40 CORRIDOR NORTH
TO THE FORECAST AREA BORDER. THEREFORE A WINTER WEATHER ADVISORY
HAS BEEN ISSUED FOR COUNTIES NORTH OF THE I-40 CORRIDOR IN BOTH
EASTERN ARKANSAS AND WEST TENNESSEE.
AFTER MIDNIGHT THE WINTER PRECIPITATION IS EXPECTED TO MOVE
FARTHER SOUTH INTO NORTH MISSISSIPPI AND EVENTUALLY INTO THE
TUPELO AREA. SINCE ANY MOISTURE WILL BE SHORT-LIVED BY THE TIME
COLD AIR MAKES ITS WAY DOWN TO NORTH MISSISSIPPI...NO SNOW OR
SLEET ACCUMULATION IS EXPECTED. SOME FLURRIES WILL BE POSSIBLE IN
THE MORNING AS THE SYSTEM EXITS THE REGION MONDAY MORNING.
MONDAY MORNING WILL BE QUITE COLD AND ANY ACCUMULATIONS WILL
LIKELY STILL BE ON THE ROADS. FOR THIS...A SPECIAL WEATHER
STATEMENT HAS BEEN ISSUED FOR THE AREA AS WELL AS THE HAZARDOUS
WEATHER OUTLOOK UPDATED. ROADS WILL LIKELY BE SLICK.
ON MONDAY AFTERNOON A BRIEF WARMUP IS EXPECTED WITH HIGHS
PREDOMINANTLY IN THE 40S WITH SOME 30S IN NORTHEAST ARKANSAS. SOME
SNOW MAY STILL BE ON THE GROUND THOUGH. ANOTHER FAST MOVING SYSTEM
IS EXPECTED TO BRING RAIN TO THE ENTIRE MID-SOUTH BY LATE MONDAY
NIGHT INTO TUESDAY AFTERNOON. AS THE RAIN OVERSPREADS THE COLD AIR
IN NORTHEAST ARKANSAS AND FAR NORTHWEST TENNESSEE...A CHANCE OF
FREEZING RAIN WILL BE POSSIBLE. FOR NOW THERE MAY BE SOME
ACCUMULATIONS ON ELEVATED SURFACES. WILL CONTINUE TO MONITOR THE
SITUATION THIS SYSTEM IS EXPECTED TO MOVE QUICKLY AND FREEZING
RAIN WILL CHANGE OVER TO RAIN BY TUESDAY AFTERNOON.
LONG TERM...WEDNESDAY WILL ONLY SEE HIGHS IN THE 30S AS COLD AIR
FUNNELS IN BEHIND THE SYSTEM. WEDNESDAY AND THURSDAY WILL BE DRY
AND COLD BEFORE ANOTHER SYSTEM MOVES INTO THE FORECAST AREA BY
FRIDAY MORNING. THIS SYSTEM WILL BRING ANOTHER ROUND OF WINTER
WEATHER TO THE MID-SOUTH. THIS SYSTEM RIGHT NOW APPEARS TO BE MUCH
STRONGER THAN THE ONE WE WILL SEE TOMORROW NIGHT.
AC3
&&
.AVIATION...
00Z TAF CYCLE
FOR KJBR...COLD FRONT IS ON THE MOVE AND WILL BE PASSING THROUGH THE
SITE LATER THIS EVENING WITH CURRENT MVFR CIGS SLOWLY LOWERING TO
IFR AFTER MIDNIGHT. NORTH WINDS BEHIND THE FRONT WILL INCREASE WITH
GUSTS ABOVE 20KTS. AS COLDER AIR FILTERS IN BY SUNRISE...RAIN WILL
BEGIN MIXING WITH SLEET...CHANGING TO A SNOW AND SLEET MIX BY MID
MORNING AND EVENTUALLY TO ALL SNOW BY LATE AFTERNOON. CIGS WILL
SLOWLY LOWER FROM IFR TO LIFR AND VISIBILITIES WILL DROP FROM
SNOWFALL TO LIFR DURING THE DAY.
FOR KMEM...RAIN SHOWER AND LOWERING CIGS CAN BE ANTICIPATED THIS
EVENING AHEAD OF AN APPROACHING COLD FRONT. MVFR CIGS SHOULD
DEVELOP AFTER 03Z WITH INCREASING COVERAGE OF RAIN SHOWERS. WINDS
SHOULD REMAIN AT OR ABOVE 10 KTS OVERNIGHT...INITIALLY
SOUTHWESTERLY THEN BECOMING NORTHERLY BEHIND THE COLD FRONT. THE
FRONT SHOULD MOVE THROUGH THE TERMINAL AROUND 07Z WITH IFR CIGS
DEVELOPING POST FRONTAL AND CONTINUING THROUGH SUNDAY. RAIN SHOULD
BECOME WIDESPREAD BEHIND THE FRONT LATE TONIGHT THROUGH SUNDAY.
FOR KMKL...SIMILAR TO KMEM INCREASING RAIN CHANCES AND LOWERING
MVFR CIGS WILL BECOME COMMON LATER THIS EVENING PRIOR TO THE
FRONTAL PASSAGE EXPECTED AROUND 07/08Z WITH NORTH WINDS EXPECTED
BEHIND THE FRONT. RAIN SHOULD BECOME WIDESPREAD AT KMKL LATE
TONIGHT INTO SUNDAY WITH IFR CIGS.
FOR KTUP...CONDITIONS WILL START OFF VFR...WITH IFR STRATUS EXPECTED
TO SURGE NORTHWARD AFTER MIDNIGHT...WITH LIGHT RAIN ALSO DEVELOPING.
A COLD FRONT WILL MOVE THROUGH THE SITE NEAR SUNRISE WITH IFR CIGS
SLOWLY LOWERING TO LIFR DURING THE DAY AS RAIN INTENSITY INCREASES
TO MODERATE. WINDS WILL BE SOUTH AROUND 8KTS AHEAD OF THE
FRONT...VEERING NORTHEASTERLY AND BECOMING GUSTY BEHIND THE FRONT.
JLH/JAB
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 36 38 28 42 / 90 90 80 10
MKL 35 37 28 42 / 90 90 80 10
JBR 32 32 25 36 / 70 80 80 10
TUP 49 49 32 46 / 40 90 80 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR CLAY-CRAIGHEAD-GREENE-LAWRENCE-MISSISSIPPI-
POINSETT-RANDOLPH.
MO...WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR DUNKLIN-PEMISCOT.
MS...NONE.
TN...WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR DYER-LAKE-LAUDERDALE-OBION-TIPTON.
WINTER WEATHER ADVISORY FROM NOON SUNDAY TO MIDNIGHT CST SUNDAY
NIGHT FOR CARROLL-CROCKETT-DECATUR-GIBSON-HAYWOOD-HENDERSON-
HENRY-MADISON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1147 PM CST SAT FEB 1 2014
.AVIATION...
FRONT IS STILL CRAWLING SOUTHWARD AND HASN`T REACHED CLL YET BUT
SHOULD AROUND 07-08Z. CIGS ARE IFR OR LIFR ACROSS THE AREA (EXCEPT
CLL) AS WAS EXPECTED AND THESE SHOULD CONTINUE MOST OF THE NIGHT
WITH SLOW IMPROVEMENT POSSIBLE FOR CLL AREA BUT WILL MOST LIKELY
HOVER IN THE 1000-1500 FT RANGE THERE. ELSEWHERE CIGS 300-800 WILL
BE COMMON. SEA FOG GETTING THICKER AT TIMES AT GLS AND LL WINDS
STILL BACKED THERE. TOWARD MORNING THOUGH THE WINDS VEER AND SO
VISBY WILL PROBABLY CREEP BACK UP. SPRINKLES CONTINUE IN WAA
PATTERN AND AS LLJ SHIFTS EAST EXPECT THAT DRIZZLE AND LIGHT RAIN
WILL INCREASE IN COVERAGE ESPECIALLY AFTER 10-12Z AS LL
CONVERGENCE INCREASES AND UPPER LEVEL DIVERGENCE OVERSPREADS THE
REGION PRODUCING DEEPER LIFT. SHOWERS ARE POSSIBLE WITH THE LAYER
OF INSTABILITY ALOFT BUT BY 15Z OR SO THE PROFILE SHOULD JUST
SUPPORT UPGLIDE RAINS THOUGH MAYBE WIDESPREAD. RAINS TAPER OFF IN
THE LATE AFTERNOON AND WINDS PICKUP NOTICEABLY IN THE AFTERNOON
BECOMING GUSTY. CIGS SHOULD BECOME MVFR BY 21-03Z ACROSS THE
REGION.
45
&&
.PREV DISCUSSION... /ISSUED 942 PM CST SAT FEB 1 2014/
DISCUSSION...
NO MAJOR CHANGES WITH THE OVERALL FCST AS THE COLD FRONT REMAINS
ROUGHLY ON TIME FOR FROPA OVER THE NORTHERN ZONES JUST AFTER MID-
NIGHT...THEN PROGRESSING TO THE COASTLINE BY NOON SUN. MEANWHILE
AHEAD OF THIS BOUNDARY...LOW CLOUDS/PATCHY FOG WILL BE THE ISSUE
(WITH THE MORE DENSE AREAS OF SEA FOG PREVAILING RIGHT ALONG THE
COAST/BEACHES). WINDS JUST ABOVE THE SFC APPEAR TO BE STAYING ON
THE HIGH SIDE (AS PER HGX VAD) SO NOT EXPECTING WIDESPREAD DENSE
FOG/REALLY LOW VISIBILITIES FOR THE INLAND AREAS THROUGH SUNRISE
ATTM. 41
PREV DISCUSSION... /ISSUED 754 PM CST SAT FEB 1 2014/
AVIATION...VERY MOIST LL IN PLACE OVER THE AREA WITH ESE TO SE
FLOW. A FEW SPRINKLES DOTTING THE AREA BUT BECOME MORE SCATTERED
NEAR THE COLD FRONT. AT 01Z THE FRONT WAS CREEPING SOUTH AT ABOUT
7-8 KNOTS AND SHOULD REACH CLL AROUND 07-09Z. CIGS ACROSS THE
REGION SHOULD CONTINUE TO FALL AND EXPECT WIDESPREAD IFR CIGS AND
LIKELY DROPPING INTO LIFR 300-500 FT. WITH THE ARRIVAL OF THE
FRONT THE CIGS MAY RISE SLIGHTLY BUT LIGHT RAIN SHOULD BECOME MORE
COMMON AND WILL KEEP THE LL MOIST. SEA FOG WAS APPARENT THIS
AFTERNOON AND HAS MOVED ACROSS THE ISLAND WITH GLS VISBY DOWN TO
2-5 MILES. EXPECT THAT VISBY 2-5 MILE VISBY WILL SPREAD INLAND AS
TEMPERATURES VERY SLOW LOWER FROM THE UPPER 60S TO THE LOWER TO
MID 60S. RR OF UPPER JET TRAVERSES THE AREA SUNDAY AND EXPECT THAT
LIGHT RAIN SHOULD BE FAIRLY WIDESPREAD. DRYING SETS IN WITH 850
FROPA 00Z IN THE CLL/UTS AREAS AND SHOULD BE THE END OF THE
PRECIP. STRONG INVERSION SHOULD REMAIN AND TRAPPED LL MOISTURE
WILL KEEP CIGS OF 1000-1500 IN PLACE THROUGH AT LEAST EARLY MONDAY
MORNING. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 46 48 35 51 44 / 40 50 10 10 60
HOUSTON (IAH) 63 63 39 52 46 / 40 70 20 10 40
GALVESTON (GLS) 57 61 42 50 50 / 30 70 40 10 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...41
AVIATION/MARINE...45
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1012 PM CST SAT FEB 1 2014
.DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 06Z TAF`S.
&&
.AVIATION...FOG IS BEGINNING TO SPREAD ACROSS THE COASTAL COUNTIES
AND A FEW LOCATIONS ACROSS INLAND AREAS THIS EVENING. AREAS OF FOG
WILL CONTINUE TO SPREAD ACROSS S TX OVERNIGHT...LOWERING
VISIBILITIES AND CIGS TO LIFR/IFR LEVELS...ESPECIALLY FROM ALI TO
VCT. TEH VSBY AT CRP IS EXPECTED TO BE SLIGHTLY HIGHER DUE TO
ELEVATED WINDS...HOWEVER THE CIGS ARE EXPECTED TO LOWER TO IFR
LEVELS AT TIMES. A COLD FRONT WILL MOVE THROUGH VCT EARLY SUNDAY
MORNING WITH CONDITIONS EXPECTED TO IMPROVE BY AROUND 13Z-15Z.
AREAS FARTHER SOUTH SHOULD IMPROVE 15Z OR SO. CIGS ARE EXPECTED TO
REMAIN AT MVFR LEVELS THE REMAINDER OF THE DAY AND INTO SUNDAY
NIGHT. STRONG GUSTY N WINDS WILL DVLP BY EARLY AFTERNOON THEN
DIMINISH BY SUNDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 955 PM CST SAT FEB 1 2014/
DISCUSSION...MADE SOME ADJUSTMENTS TO FORECAST FOR FRONTAL TIMING
AND AFFECTS. TIMING IS STILL LOOKING PRETTY GOOD...BUT MAYBE AN
HOUR OR SO FASTER. BIGGER CHANGE WAS WITH COOLING TEMPERATURES
AND LOWERING DPTS FASTER. RUC HAS A GOOD HANDLE ON TIMING...BUT
MAY BE DECREASING TEMPS TOO QUICKLY...WITH MOST OF THE AREA IN THE
MID 40S BY EARLY AFTERNOON. HAVE BROUGHT TEMPS INTO THE 50S FOR
EVERYONE LATE MORNING/EARLY AFTERNOON...AND SOME UPPER 40S NORTH.
PREV DISCUSSION... /ISSUED 544 PM CST SAT FEB 1 2014/
DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 00Z TAFS.
AVIATION...SKIES HAVE CLRD OUT ACROSS MUCH OF S TX EXCEPT FOR
AROUND VCT AREA THIS AFTERNOON. CLOUDS ARE EXPECTED TO SPREAD
ACROSS S TX OVERNIGHT ALONG WITH DVLPG FOG. A MIX OF STRATUS AND
FOG WILL LEAD TO MVFR CIGS/VSBYS THIS EVENING AND IFR/LIFR
OVRNIGHT...ESPECIALLY EAST OF A HEBBRONVILLE TO TILDEN LINE. A
COLD FRONT IS EXPECTED TO MOVE THROUGH S TX SUNDAY MORNING WITH A
WSHFT INITIALLY ACROSS THE VCT AREA BETWEEN 13-15Z AND
LRD...ALI...CRP BTWN 15-17Z. WINDS WILL STRENGTHEN FROM THE N
THROUGH SUNDAY AFTERNOON. THERE IS A CHANCE OF -SHRA`S ALONG AND
BEHIND THE COLD FRONT WHICH IS EXPECTED TO KEEP CIGS AT MVFR
LEVELS THROUGHOUT THE DAY.
PREV DISCUSSION... /ISSUED 432 PM CST SAT FEB 1 2014/
SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...SOUTHERLY FLOW
TONIGHT WILL CONTINUE TO FUNNEL MOISTURE INTO THE LOWER LVLS AHEAD
OF AN APPROACHING COLD FRONT. SHORTWAVE TROUGH WILL SWEEP ACROSS
THE STATE AND BRING DOWN AN ASSOCIATED COLD FRONT SUNDAY MORNING.
MODELS IN FAIR AGREEMENT WITH TIMING OF FROPA...WITH IT ENTERING
THE THE NORTHERN BORDERS OF THE CWA RIGHT AROUND 12Z AND IT
PUSHING OFFSHORE IN THE EARLY AFTERNOON. TEMPERATURES WILL BE A
LITTLE TRICKY WITH HIGHS EXPECTED TO BE REACHED IN THE MORNING...AND
FALLING TEMPERATURES ACROSS THE REGION IN THE AFTERNOON TOMORROW.
SUFFICIENT UPPER LVL SUPPORT WITH THIS FRONT AND PLENTIFUL
MOISTURE SHOULD PROVIDE A SLIGHT CHANCE TO CHANCE FOR SHOWERS TO DEVELOP
ACROSS THE REGION...BEGINNING TONIGHT AND INCREASING TOMORROW.
KEPT POPS HIGHEST OVER THE NORTHEAST ZONES WHERE BETTER MOISTURE
AND DYNAMICS WILL BE FOR DEVELOPMENT. FOG WILL BE ANOTHER ISSUE
TO CONTEND WITH TONIGHT INTO TOMORROW MORNING AHEAD OF THE FROPA.
EXPECT WINDS OVERLAND TO DIMINISH MORE TONIGHT...AND AREAS OF FOG
MAY DEVELOP ACROSS COASTAL BEND...PLAINS...AND VICTORIA
CROSSROADS. FOG OVER THE BAYS AND NEARSHORE WATERS WILL BE MORE
DENSE TONIGHT THAN THE PREVIOUS NIGHT AS WELL...WITH LOWER
WINDS...AND HIGHER DEWPOINTS OVER THE COOL WATERS.
LONG TERM (MONDAY THROUGH SATURDAY)...LONG TERM FORECAST A BIT OF
A ROLLER COASTER ON TEMPS AND WX. FORECAST BEGINS WITH COOL
AIRMASS STILL IN PLACE MONDAY UNDER MOSTLY CLOUDY TO OVERCAST
SKIES. HIGHS ONLY IN THE LOW 50S ON MONDAY WITH NORTH WIND
WEAKENING AND VEERING NORTHEAST AS HIGH PRESSURE MOVES EAST.
SOUTHERLY LOW LEVEL FLOW AND WAA/ISENTROPIC UPGLIDE INCREASE
MONDAY NIGHT IN RESPONSE TO ROBUST SHORTWAVE AND DIGGING TROUGH
COMING OUT OF THE DESERT SOUTHWEST INTO WEST TEXAS. ISOLATED TO
SCATTERED SHOWERS LOOK TO DEVELOP ACROSS SOUTH TEXAS LATE MONDAY
NIGHT THROUGH TUESDAY MORNING. THE SHORTWAVE LIFTS NORTHEAST INTO
NORTH TEXAS DURING THE DAY ON TUESDAY...AND DRAGS BOUNDARY THROUGH
THE AREA WITH DRYING/CLEARING OCCURRING WEST TO EAST. THIS RESULTS
IN MUCH WARMER TEMPERATURES HERE TUESDAY AFTERNOON COMPARED TO
MONDAY...WITH HIGHS TUESDAY INTO THE LOW TO MID 70S AWAY FROM THE
IMMEDIATE COAST. AS THE SHORTWAVE DEPARTS TO THE NORTHEAST A
STRONGER RE-ENFORCING COLD FRONT MOVES THROUGH SOUTH TEXAS
WEDNESDAY MORNING. INITIALLY DRY ALONG AND BEHIND THE FRONT
WEDNESDAY...BUT COOLER WITH HIGHS BACK INTO THE 50S TO AROUND 60.
THEN THURSDAY INTO FRIDAY ANOTHER TROUGH DIGS OVER THE WESTERN
U.S. INTO THE DESERT SOUTHWEST. COASTAL TROUGHING DEVELOPS KEEPING
THE COLD AIR IN PLACE ACROSS SOUTH TEXAS...AND ISENTROPIC UPGLIDE
DEVELOPS IN RESPONSE TO THE APPROACHING SHORTWAVE...PRODUCING
CLOUDS AND CHANCES FOR LIGHT RAIN ACROSS THE REGION. TEMPERATURES
MAY NOT MAKE IT OUT OF THE LOW TO MID 40S THURSDAY AND UPPER 40S
FRIDAY FOR MANY AREAS. THAT UPPER LEVEL TROUGH LOOKS TO MOVE
ACROSS THE SOUTHERN PLAINS ON SATURDAY...PUSHING ANOTHER COLD
FRONT THROUGH THE AREA BUT RESULTING IN CLEARING SKIES AND
ACTUALLY WARMER TEMPERATURES SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 64 67 39 52 49 / 10 30 10 10 40
VICTORIA 58 59 35 53 48 / 20 50 10 10 50
LAREDO 63 66 39 57 48 / 10 20 10 10 20
ALICE 62 67 38 53 47 / 10 30 10 10 40
ROCKPORT 63 67 39 50 50 / 20 40 10 10 50
COTULLA 56 58 35 55 45 / 10 30 10 10 30
KINGSVILLE 64 68 39 53 48 / 10 30 10 10 40
NAVY CORPUS 64 67 37 52 51 / 10 30 10 10 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM 3 PM SUNDAY TO 6 AM CST MONDAY FOR THE
FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT
ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT
O`CONNOR...COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS
OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT
ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM.
DENSE FOG ADVISORY UNTIL 9 AM CST SUNDAY FOR THE FOLLOWING
ZONES: BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT
O`CONNOR...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL OUT 20 NM.
&&
$$
TE/81...AVIATION
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
437 AM EST SUN FEB 2 2014
.SYNOPSIS...
A COLD FRONT TRAILING FROM NEW YORK TO ARKANSAS WILL MOVE
SOUTHEAST ACROSS THE REGION TODAY. LOWS PRESSURE WILL TRACK ALONG
THIS FRONT AND INTO THE CAROLINAS BY TONIGHT. HIGH PRESSURE MOVES
ACROSS THE OHIO VALLEY INTO THE MID ATLANTIC ON TUESDAY...BEFORE
ANOTHER LOW AND COLD FRONT MOVE THROUGH THE AREA ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EST SUNDAY...
BROAD SOUTHWEST FLOW AT 500MB TODAY AND TONIGHT. FORECAST AREA WILL
BE UNDER RIGHT REAR QUADRANT OF UPPER JET OVERNIGHT. MORE ORGANIZED
SHORT WAVE DOES NOT GET CLOSE UNTIL AFTER MIDNIGHT. BEGINNING OF
COOLING WILL ALSO BE LATE TONIGHT. ANY CHANGE OVER FROM RAIN TO
SLEET AND SNOW IN THE FAR NORTHWEST WOULD NOT BE UNTIL AFTER
MIDNIGHT.
DEEP MOISTURE STAYS WEST OF THE BLUE RIDGE TODAY. BETTER PUSH TO THE
EAST WILL BE OVERNIGHT. TIMING IS SIMILAR TO PAST FEW MODELS RUNS
BRINGING LEADING EDGE OF RAIN INTO SOUTHEAST WEST VIRGINIA AROUND
12Z/7AM TODAY. HRRR AND LOCAL WRF ALSO BRING THE RAIN INTO SOUTHEAST
WEST VIRGINIA BETWEEN 11Z/6AM AND 14Z/9AM.
SURFACE COLD FRONT ENTERS THE FORECAST AREA FROM THE WEST THIS
MORNING AND MOVES SLOWLY SOUTHEAST...EVENTUALLY INTO NORTH CAROLINA
THIS EVENING. LOW PRESSURE MOVING ALONG THE FRONT WILL BE OVER THE
WESTERN CAROLINAS LATE TONIGHT WHICH WILL BACK THE LOW LEVEL WINDS
AND HELP ENHANCE LOW LEVEL CONVERGENCE AND LIFT.
PRECIPITABLE WATER VALUES RISE INTO THE 0.75 TO 1.0 INCH RANGE BY
00Z/7PM TONIGHT. AHEAD OF THE FRONT TODAY SURFACE DEW POINTS SURGE
WELL INTO THE MID TO UPPER 40S. GFS AND LOCAL WRF ARE SHOWING AN
AXIS OF HEAVIER QPF AMOUNTS FROM AROUND SMYTH/TAZEWELL COUNTIES INTO
ROCKBRIDGE AND AMHERST COUNTIES. COULD HAVE 0.5 TO 0.75 INCHES OF
RAIN ALONG THIS AXIS BY MONDAY MORNING.
GFS BUFKIT WAS SLIGHTLY COLDER WITH THE TEMPERATURE PROFILE BY 12Z
THAN THE NAM. APPEARS ANY MIX OR CHANGE TO SLEET WOULD BE AFTER
09Z/4AM TONIGHT AND WOULD BE CONFINED TO SOUTHEAST WEST VIRGINIA
INTO BATH COUNTY VIRGINIA.
STARTING OFF RELATIVELY MILD THIS MORNING. EVEN WITH THE INCREASING
CLOUD COVER...NOT FAR TO REACH TEMPERATURES IN THE LOWER 50S TO
LOWER 60S FOR MAXIMUM TEMPERATURES.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 430 AM EST SUNDAY...
WIDESPREAD PRECIPITATION WILL BE ONGOING MONDAY MORNING ACROSS THE
ENTIRE BLACKSBURG FORECAST AREA AS SOUTHERN STREAM SHORT WAVE AND
ASSOCIATED AREA OF LOW PRESSURE RIDES NORTHEAST ALONG FRONTAL SYSTEM
STALLED JUST TO OUR SOUTH. VERY BROAD UPWARD VERTICAL MOTION FIELD
RESULTING FROM GOOD ISENTROPIC LIFT IN LOWER 200 MILLIBARS OF THE
TROPOSPHERE COMBINED WITH IMPRESSIVE UPPER DIFFLUENT AREA FROM
COUPLED JET MAXIMA WILL GRADUALLY LIFT OFF TO THE NORTH AND EAST BY
AFTERNOON...ALLOWING FOR PRECIPITATION TO END IN MOST AREAS AS THE
AFTERNOON PROGRESSES.
SUFFICIENT COLD AIR MAY BE DRAWN INTO THE NORTHWESTERN PERIPHERY OF
THE STORM TO ALLOW FOR CHANGEOVER TO SNOW/SLEET ACROSS THE HIGHER
TERRAIN OF GREENBRIER COUNTY WV BY DAYBREAK MONDAY...AND AS FAR
SOUTH AND EAST AS THE REMAINDER OF SOUTHEAST WV...ADJACENT AREAS OF
SOUTHWEST VA...INTO THE ALLEGHANY HIGHLANDS AND SOUTHERN SHENANDOAH
VALLEY OF VA AS THE MORNING PROGRESSES. HOWEVER...ALL OF THE MODELS
CONTINUE WITH RECENT TRENDS OF NOT SUPPORTING AN AGGRESSIVE ENOUGH
PUSH OF COLDER AIR INTO THE WESTERN FLANKS OF THE STORM BEFORE THE
AREA LOSES THE MID LEVEL MOISTURE RUNNING THROUGH THE DENDRITIC
LAYER. AS A RESULT...ANY SNOWFALL ACCUMULATIONS WILL LIKELY BE
MINIMAL...PERHAPS NO MORE THAN 1-3 INCHES...AND MAINLY CONFINED TO
THE HIGHER ELEVATIONS OF WESTERN GREENBRIWER COUNTY EAST INTO
PORTIONS OF THE ALLEGHANY HIGHLANDS.
WEATHER FOR LATER MONDAY AFTERNOON INTO MONDAY NIGHT WILL BE
GOVERNED BY COLD ADVECTION PATTERN WITH PLENTY OF LOW LEVEL CLOUDS
AS SURFACE RIDGE ON BACKSIDE OF STORM BUILDS EAST OF OUT THE OHIO
VALLEY...THEN SOUTHWARD ON THE EAST FLANKS OF THE APPALACHIANS
AS COOL WEDGE IS ESTABLISHED.
NEXT SOUTHERN STREAM SYSTEM EXPECTED TO BEGIN TO MAKE A MOVE
NORTHEAST TOWARD THE AREA ON TUESDAY...PASSING WEST OF THE AREA ON
TUESDAY NIGHT AS SECONDARY LOW PRESSURE DEVELOPS OVER/NEAR THE
DELMARVA AREA ON BAROCLINIC ZONE ON EAST SIDE OF COASTAL COOL WEDGE.
THIS SYSTEM WILL BRING ANOTHER PERIOD OF RAIN TO THE AREA...MOST
NOTABLY LATE TUESDAY AFTERNOON THROUGH TUESDAY NIGHT. LATER
ARRIVAL OF MAIN BODY OF PRECIPITATION SHIELD SHOULD ALLOW FOR
SURFACE TEMPERATURES TO CLIMB TO ABOVE FREEZING IN MOST AREAS ON
TUESDAY SUCH THAT ANY GLAZING SHOULD BE VERY LIMITED...AND
LOCALIZED TO THE AREAS NEAR THE BLUE RIDGE NORTH INTO THE
ALLEGHANY HIGHLANDS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 PM EST SATURDAY...
A COLD FRONT CROSSES ON WEDNESDAY WITH MORE SHOWERS AND ANOTHER
SURGE OF WARM AIR.
FORECAST THU NIGHT-SAT REMAINS COMPLICATED. HOWEVER...THE NEW 12Z
ECMWF HAS TRENDED FURTHER INLAND WITH THE TRACK OF THE LOW
PRESSURE SYSTEMS AFFECTING US FRI-SAT...WHICH TRENDS TOWARD THE
GEFS/ECWMF ENSEMBLE/CMC AND GFS. LEANED TOWARD A BLEND OF THE
ECMWF/CMC/GFS AND WPC.
FIRST...FRONT EXITS EAST GOING INTO WED EVENING WITH UPSLOPE SNOW
SHOWERS ACROSS SE WV...ALTHOUGH SFC FLOW BECOMES ANTICYCLONIC
PRETTY FAST AND THIS FAVORS A LIMITED THREAT.
LOOKING DRY HEADING INTO THURSDAY AND THURSDAY EVENING AS A STRONG
SURFACE HIGH 1041 ECWMF/1047 GFS BUILDS ESE FROM THE NRN HIGH PLAINS
INTO THE MIDWEST/WRN OHIO VALLEY BY THURSDAY EVENING. WHILE THIS
OCCURS...THE UPPER LEVEL FLOW REMAINS FAST AND SPLIT WITH SRN JET
SITUATED ACROSS SRN TX INTO THE SOUTHEAST WHILE NRN STREAM IS ACROSS
THE GREAT LAKES.
THE FORECAST PROBLEMS ARISE LATE THU NIGHT-SAT. THE ECMWF IS FASTER
IN BRINGING PCPN INTO THE SW WITH A LIGHT QPF SHOWING UP IN THE
NC MTNS BY 12Z FRIDAY. THE GFS IS 10MB STRONG THAN THE ECMWF WHICH
SLOWS THINGS DOWN. HOWEVER...WILL ALLOW FOR THE COLDER TEMPS OF
THE GFS BUT EDGE PCPN INTO THE NC MTNS AS SNOW BY FRIDAY MORNING.
DURING THE DAY FRIDAY...THE SFC HIGH STARTS TO WEDGE
SOUTHEAST...WHILE SFC FRONT AND LOW FORMS ACROSS THE GULF COAST
WITH A STRONGER SFC LOW ACROSS THE COLORADO ROCKIES. THIS WILL BE
A PERIOD WHERE WILL WATCH PIECES OF SHORTWAVE ENERGY MOVE NE ALONG
THE SOUTHEAST INTO THE MID ATLANTIC AND WHERE THE COLDER AIR STAYS
IN THE LOW LVLS WITH A WARM NOSE STARTING TO WORK IN FROM THE SW.
COULD BE A WINTRY MESS FRIDAY...WITH THE ECMWF SHOWING A
CHANGEOVER TOWARD COLD RAIN BY THE AFTERNOON...WHILE THE GFS KEEPS
THE 8H TEMPS COLD ENOUGH FOR A MORE RAIN/SNOW THREAT...WITH SOME
ICE POTENTIAL.
THE MODELS THEN DRAG THE ROCKIES LOW AND UPPER SYSTEM INTO THE SRN
PLAINS HEADING INTO SAT WHILE ANOTHER LOW FORMS ACROSS THE GULF
COAST STATES. STILL A WEDGE IS INDICATED OFF THE GFS WHILE THE
ECWMF BUMPS THE FRONTAL BOUNDARY MORE OVER WRN VA/NC KEEPING IT
RAIN. GFS SHOWING RAIN AS WELL AS THICKNESSES WARM AHEAD OF THE
UPPER TROUGH WITH STRONG SW FLOW...SO SATURDAY WILL BE WET WITH
MAYBE NRN CWA EXPERIENCING A WINTRY MIX.
SO IN A NUTSHELL...THERE IS A TREND TOWARD A WARMER/FURTHER INLAND
TRACK...BUT WE ARE NOT OUT OF THE WOODS YET FOR WINTER WX...AS
STATED FRIDAYS SYSTEM COULD BE ICY FOLLOWED BY RAIN SATURDAY. THE
CABOOSE WITH THIS SYSTEM IS INLAND AS WELL AS THE 12Z ECMWF HAS
BACKED OFF ON THE COASTAL LOW DEEPENING OFF THE NC/VA COAST SAT INTO
SUNDAY...AND HAS A TRACK INLAND OVER THE BLUE RIDGE SATURDAY
NIGHT...WHILE THE GFS IS WEST OF THE APPALACHIANS. IF THIS OCCURS
WILL BE A RAIN CHANGING TO SNOW SCENARIO BEFORE ENDING WHILE THE
NORTHEAST GETS THE HEAVY SNOW. WITH THE STRENGTH OF THE LOW AND
TROUGH...THERE COULD BE SOME WIND AND HEAVY MOUNTAIN SNOW SHOWER
ISSUES SUNDAY. STAY TUNED.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
AS OF 1235 AM EST SUNDAY...
SPLIT WEATHER SYSTEMS WILL AFFECT THE BLACKSBURG TERMINAL FORECAST
AREA OVERNIGHT AS WEAK COASTAL SYSTEM TRACKS NORTHEAST ALONG THE
NC/SC COAST...SUPPORTING THE ADVECTION OF CLOUD DECK IN 2-4
THOUSAND FOOT RANGE AS FAR NORTH AS KDAN AND KLYH. THESE CLOUDS
EXPECTED TO GRADUALLY LIFT OFF TO THE EAST BEFORE DAYBREAK AS
LOWER LEVEL WINDS VEER INTO MORE OF A SOUTHWESTERLY COMPONENT.
HOWEVER...ADDITIONAL MOISTURE UPSTREAM IN ADVANCE OF NEXT
SOUTHERN STREAM SYSTEM AND APPROACHING COLD FRONT LIKELY TO SPREAD
ANOTHER DECK OF STRATOCUMULUS IN 3-5 THOUSAND FOOT RANGE INTO
SOUTHEASTERN WV TERMINAL FORECAST SITES BY/AROUND 08Z/3AM...AND TO
SITES EAST OF THE BLUE RIDGE BEFORE 13Z/9AM.
FURTHER NW...A SLOW MOVING FRONTAL SYSTEM/BAROCLINIC ZONE WAS
SINKING SOUTHEASTWARD THROUGH THE OH VALLEY. GIVEN THAT THE FLOW
ALOFT IS NEARLY PARALLEL TO THE FRONTAL BOUNDARY...EXPECT ONLY
SLOW PROGRESS TO THE SE WITH THE FRONT FOR THE REST OF TONIGHT...
WITH PCPN HOLDING OFF UNTIL WELL AFT DAYBREAK.
WHEN THE PCPN ARRIVES...LOW- LEVEL THICKNESS VALUES WELL ABOVE
THE CRITICAL 1310DM VALUE...SO ALL PCPN SHOULD BE LIQUID...NAMELY
-SHRA. THIS SHOULD OCCUR MAINLY AFT 21Z/4PM ACROSS THE SE WV SITES...
AND NOT UNTIL AFTER THE TERMINAL FORECAST PERIOD ELSEWHERE.
FLIGHT CONDITIONS EXPECTED TO WORSEN TO MVFR TO IFR DUE TO
RESTRICTIONS TO BOTH CEILING AND VSBY AS WIDESPREAD RAIN
OVERSPREADS THE ENTIRE AREA...MAINLY AFTER 06Z/1AM MONDAY...
CONTINUING THROUGH MUCH OF MONDAY MORNING BEFORE GRADUALLY
IMPROVING MONDAY AFTERNOON AS SYSTEM PASSES OFF TO THE EAST OF THE
AREA. PRECIPITATION MAY POSSIBLY MIX WITH OR CHANGE TO SNOW
AND/OR SLEET LATE SUNDAY NIGHT/MONDAY MORNING BEFORE ENDING NORTH
OF A KBLF- KROA- KLYH LINE...WITH GREATEST THREAT CONFINED TO
AREAS NEAR KLWB.
EXTENDED AVIATION DISCUSSION...
HIGH PRESSURE WEDGES SOUTH FROM NEW ENGLAND MONDAY NIGHT INTO
TUESDAY WHICH WILL HOLD COLD AIR NEAR THE SURFACE. MODELS ARE
SHOWING CONSISTENT TRENDS BRINGING WINTER PRECIPITATION INTO THE
AREA BY TUESDAY. A STORM SYSTEM MOVING OUT OF THE GULF COAST
TUESDAY AND INTO THE MID ATLANTIC REGION ON WEDNESDAY WILL PROLONG
THE CHANCE OF PRECIPITATION...AS WELL AS SUB VFR CEILINGS AND
VISIBILITIES. THEN IT DRIES OUT HEADING INTO WED NIGHT-THU WITH
VFR RETURNING. THE NEXT MAJOR SYSTEM WILL AFFECT THE AREA BY NEXT
WEEKEND.
&&
.HYDROLOGY...
AS OF 420 AM EST SUNDAY...
WIDESPREAD RAINFALL IS EXPECTED ACROSS THE AREA TODAY INTO MONDAY
MORNING. ONE HALF TO ONE INCH OF RAINFALL IS LIKELY. WITH THE
GROUND FROZEN SOLID...MUCH OF THIS RAINFALL WILL RUNOFF INTO AREA
RIVERS. AT THIS TIME MODERATE WITHIN BACK RISES ARE EXPECTED ALONG
MAINSTEM RIVERS. WE WILL CONTINUE TO MONITOR THE RAINFALL AND ITS
IMPACT THROUGHOUT THE EVENT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...WERT
LONG TERM...KM/WP
AVIATION...KM/RAB/WERT/WP
HYDROLOGY...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
425 AM EST SUN FEB 2 2014
.SYNOPSIS...
A COLD FRONT TRAILING FROM NEW YORK TO ARKANSAS WILL MOVE
SOUTHEAST ACROSS THE REGION TODAY. LOWS PRESSURE WILL TRACK ALONG
THIS FRONT AND INTO THE CAROLINAS BY TONIGHT. HIGH PRESSURE MOVES
ACROSS THE OHIO VALLEY INTO THE MID ATLANTIC ON TUESDAY...BEFORE
ANOTHER LOW AND COLD FRONT MOVE THROUGH THE AREA ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EST SUNDAY...
BROAD SOUTHWEST FLOW AT 500MB TODAY AND TONIGHT. FORECAST AREA WILL
BE UNDER RIGHT REAR QUADRANT OF UPPER JET OVERNIGHT. MORE ORGANIZED
SHORT WAVE DOES NOT GET CLOSE UNTIL AFTER MIDNIGHT. BEGINNING OF
COOLING WILL ALSO BE LATE TONIGHT. ANY CHANGE OVER FROM RAIN TO
SLEET AND SNOW IN THE FAR NORTHWEST WOULD NOT BE UNTIL AFTER
MIDNIGHT.
DEEP MOISTURE STAYS WEST OF THE BLUE RIDGE TODAY. BETTER PUSH TO THE
EAST WILL BE OVERNIGHT. TIMING IS SIMILAR TO PAST FEW MODELS RUNS
BRINGING LEADING EDGE OF RAIN INTO SOUTHEAST WEST VIRGINIA AROUND
12Z/7AM TODAY. HRRR AND LOCAL WRF ALSO BRING THE RAIN INTO SOUTHEAST
WEST VIRGINIA BETWEEN 11Z/6AM AND 14Z/9AM.
SURFACE COLD FRONT ENTERS THE FORECAST AREA FROM THE WEST THIS
MORNING AND MOVES SLOWLY SOUTHEAST...EVENTUALLY INTO NORTH CAROLINA
THIS EVENING. LOW PRESSURE MOVING ALONG THE FRONT WILL BE OVER THE
WESTERN CAROLINAS LATE TONIGHT WHICH WILL BACK THE LOW LEVEL WINDS
AND HELP ENHANCE LOW LEVEL CONVERGENCE AND LIFT.
PRECIPITABLE WATER VALUES RISE INTO THE 0.75 TO 1.0 INCH RANGE BY
00Z/7PM TONIGHT. AHEAD OF THE FRONT TODAY SURFACE DEW POINTS SURGE
WELL INTO THE MID TO UPPER 40S. GFS AND LOCAL WRF ARE SHOWING AN
AXIS OF HEAVIER QPF AMOUNTS FROM AROUND SMYTH/TAZEWELL COUNTIES INTO
ROCKBRIDGE AND AMHERST COUNTIES. COULD HAVE 0.5 TO 0.75 INCHES OF
RAIN ALONG THIS AXIS BY MONDAY MORNING.
GFS BUFKIT WAS SLIGHTLY COLDER WITH THE TEMPERATURE PROFILE BY 12Z
THAN THE NAM. APPEARS ANY MIX OR CHANGE TO SLEET WOULD BE AFTER
09Z/4AM TONIGHT AND WOULD BE CONFINED TO SOUTHEAST WEST VIRGINIA
INTO BATH COUNTY VIRGINIA.
STARTING OFF RELATIVELY MILD THIS MORNING. EVEN WITH THE INCREASING
CLOUD COVER...NOT FAR TO REACH TEMPERATURES IN THE LOWER 50S TO
LOWER 60S FOR MAXIMUM TEMPERATURES.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 341 PM EST SATURDAY...
MODEL SUITE DID TAKE A RATHER UNITED TURN TOWARDS A WARMER SOLUTION
FOR OUR AREA...SUNDAY NIGHT AND MONDAY. IT`S CUSTOMARY FOR THESE
EVENTS TO SHIFT BACK SOUTH AND TURN COLDER AGAIN INSIDE 24
HOURS...SO DIDN`T TOTALLY BUY WHAT THE MODELS WERE SELLING.
HOWEVER...COULDN`T IGNORE THE WARMER TREND SO NUDGED GRIDS IN THAT
DIRECTION. DID PUSH MUCH OF THE IMPACTFUL FROZEN PCPN INTO THE
HIGHER ELEVATIONS OF THE SOUTHERN SHENANDOAH AND SOUTHEASTERN WEST
VIRGINIA. ALSO...AREAS ABOVE 3000 FEET IN CRAIG AND GILES COUNTY
MAY ALSO ACCUMULATE SOME FROZEN PCPN. SEEMS LIKE HIGH PRESSURE
TRYING TO MOVE INTO A WEDGE POSITION...WILL NOT MAKE IT IN TIME TO
LINE UP WITH THE MORE COPIOUS PCPN AMOUNTS...AND THIS OUTCOME
SEEMS TO HAPPEN OFTEN AROUND HERE. BY MONDAY
AFTERNOON...HOWEVER...CAN`T RULE OUT A BIT OF SNOW OR FREEZING
RAIN JUST A BIT FARTHER SOUTH...POSSIBLY INTO THE NEW RIVER VALLEY
AS THE DEEPER MOISTURE PULLS OUT. ATTM...MOST OF THE PCPN SHOULD
FALL LATER SUNDAY NIGHT THROUGH MONDAY MID MORNING. IF CURRENT
FORECASTED STORM TRACK HOLDS...AND THATS STILL A SIGNIFICANT
IF...MOSTLY LOOKING AT A COLD RAIN FOR MUCH OF THE CWA. THE
NAM/GFS AND SOME OF THE SREF SOUNDINGS INDICATE THIS. ALSO THE
SREF PROBABILITIES ARE INSIGNIFICANT OUTSIDE OF THE AREAS
MENTIONED ABOVE...AS FAR AS FROZEN PCPN. RAIN MAY BE HEAVY AT
TIMES WITH AROUND 0.75" POSSIBLE. IN WESTERN GREENBRIER AND THE
HIGHEST ELEVATIONS OF THE SOUTHERN SHENANDOAH...THINKING A MIXTURE
OF RAIN/SLEET/SNOW WHICH WILL EVENTUALLY BECOME ALL SNOW FOR A
WHILE MONDAY MORNING. AS THE DEEPER MOISTURE LEAVES AND COLDER AIR
SEEPS SOUTH...TEMPS MAY FALL TO 32F AND THERE`S A CHANCE FOR LIGHT
FREEZING RAIN MONDAY AFTERNOON. A LITTLE EARLY FOR AMOUNTS...BUT
THE COMBINATION OF SNOW AND SOME SLEET WOULD JUSTIFY AN ELEVATION
ADVISORY AT THIS TIME. DID NOT FEEL COMFORTABLE WITH A WATCH
CONSIDERING THE WARMING TREND IN THE MODELS...WHICH IF IT
CONTINUES WILL CUT DOWN AMOUNTS EVEN FURTHER.
DEEPER WEDGE SETS IN MONDAY NIGHT...AND UPSLOPE FLOW AND LLVL
MOISTURE MAY COMBINE FOR LIGHT RAIN OR PERHAPS PATCH FREEZING RAIN
ALONG THE BLUE RIDGE IN NW NC NEAR DAWN TUESDAY. COLD WEDGE HANGS
THROUGH TUESDAY...AND THERE AGAIN COULD BE SOME FREEZING RAIN ACROSS
GREENBRIER AND THE SOUTHERN SHENANDOAH LATER TUESDAY AND TUESDAY
EVENING...BEFORE THE WARM SURGE SCOURS OUT THE SUBFREEZING BOUNDARY
LAYER WITH SLOWLY RISING TEMPS TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 PM EST SATURDAY...
A COLD FRONT CROSSES ON WEDNESDAY WITH MORE SHOWERS AND ANOTHER
SURGE OF WARM AIR.
FORECAST THU NIGHT-SAT REMAINS COMPLICATED. HOWEVER...THE NEW 12Z
ECMWF HAS TRENDED FURTHER INLAND WITH THE TRACK OF THE LOW
PRESSURE SYSTEMS AFFECTING US FRI-SAT...WHICH TRENDS TOWARD THE
GEFS/ECWMF ENSEMBLE/CMC AND GFS. LEANED TOWARD A BLEND OF THE
ECMWF/CMC/GFS AND WPC.
FIRST...FRONT EXITS EAST GOING INTO WED EVENING WITH UPSLOPE SNOW
SHOWERS ACROSS SE WV...ALTHOUGH SFC FLOW BECOMES ANTICYCLONIC
PRETTY FAST AND THIS FAVORS A LIMITED THREAT.
LOOKING DRY HEADING INTO THURSDAY AND THURSDAY EVENING AS A STRONG
SURFACE HIGH 1041 ECWMF/1047 GFS BUILDS ESE FROM THE NRN HIGH PLAINS
INTO THE MIDWEST/WRN OHIO VALLEY BY THURSDAY EVENING. WHILE THIS
OCCURS...THE UPPER LEVEL FLOW REMAINS FAST AND SPLIT WITH SRN JET
SITUATED ACROSS SRN TX INTO THE SOUTHEAST WHILE NRN STREAM IS ACROSS
THE GREAT LAKES.
THE FORECAST PROBLEMS ARISE LATE THU NIGHT-SAT. THE ECMWF IS FASTER
IN BRINGING PCPN INTO THE SW WITH A LIGHT QPF SHOWING UP IN THE
NC MTNS BY 12Z FRIDAY. THE GFS IS 10MB STRONG THAN THE ECMWF WHICH
SLOWS THINGS DOWN. HOWEVER...WILL ALLOW FOR THE COLDER TEMPS OF
THE GFS BUT EDGE PCPN INTO THE NC MTNS AS SNOW BY FRIDAY MORNING.
DURING THE DAY FRIDAY...THE SFC HIGH STARTS TO WEDGE
SOUTHEAST...WHILE SFC FRONT AND LOW FORMS ACROSS THE GULF COAST
WITH A STRONGER SFC LOW ACROSS THE COLORADO ROCKIES. THIS WILL BE
A PERIOD WHERE WILL WATCH PIECES OF SHORTWAVE ENERGY MOVE NE ALONG
THE SOUTHEAST INTO THE MID ATLANTIC AND WHERE THE COLDER AIR STAYS
IN THE LOW LVLS WITH A WARM NOSE STARTING TO WORK IN FROM THE SW.
COULD BE A WINTRY MESS FRIDAY...WITH THE ECMWF SHOWING A
CHANGEOVER TOWARD COLD RAIN BY THE AFTERNOON...WHILE THE GFS KEEPS
THE 8H TEMPS COLD ENOUGH FOR A MORE RAIN/SNOW THREAT...WITH SOME
ICE POTENTIAL.
THE MODELS THEN DRAG THE ROCKIES LOW AND UPPER SYSTEM INTO THE SRN
PLAINS HEADING INTO SAT WHILE ANOTHER LOW FORMS ACROSS THE GULF
COAST STATES. STILL A WEDGE IS INDICATED OFF THE GFS WHILE THE
ECWMF BUMPS THE FRONTAL BOUNDARY MORE OVER WRN VA/NC KEEPING IT
RAIN. GFS SHOWING RAIN AS WELL AS THICKNESSES WARM AHEAD OF THE
UPPER TROUGH WITH STRONG SW FLOW...SO SATURDAY WILL BE WET WITH
MAYBE NRN CWA EXPERIENCING A WINTRY MIX.
SO IN A NUTSHELL...THERE IS A TREND TOWARD A WARMER/FURTHER INLAND
TRACK...BUT WE ARE NOT OUT OF THE WOODS YET FOR WINTER WX...AS
STATED FRIDAYS SYSTEM COULD BE ICY FOLLOWED BY RAIN SATURDAY. THE
CABOOSE WITH THIS SYSTEM IS INLAND AS WELL AS THE 12Z ECMWF HAS
BACKED OFF ON THE COASTAL LOW DEEPENING OFF THE NC/VA COAST SAT INTO
SUNDAY...AND HAS A TRACK INLAND OVER THE BLUE RIDGE SATURDAY
NIGHT...WHILE THE GFS IS WEST OF THE APPALACHIANS. IF THIS OCCURS
WILL BE A RAIN CHANGING TO SNOW SCENARIO BEFORE ENDING WHILE THE
NORTHEAST GETS THE HEAVY SNOW. WITH THE STRENGTH OF THE LOW AND
TROUGH...THERE COULD BE SOME WIND AND HEAVY MOUNTAIN SNOW SHOWER
ISSUES SUNDAY. STAY TUNED.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
AS OF 1235 AM EST SUNDAY...
SPLIT WEATHER SYSTEMS WILL AFFECT THE BLACKSBURG TERMINAL FORECAST
AREA OVERNIGHT AS WEAK COASTAL SYSTEM TRACKS NORTHEAST ALONG THE
NC/SC COAST...SUPPORTING THE ADVECTION OF CLOUD DECK IN 2-4
THOUSAND FOOT RANGE AS FAR NORTH AS KDAN AND KLYH. THESE CLOUDS
EXPECTED TO GRADUALLY LIFT OFF TO THE EAST BEFORE DAYBREAK AS
LOWER LEVEL WINDS VEER INTO MORE OF A SOUTHWESTERLY COMPONENT.
HOWEVER...ADDITIONAL MOISTURE UPSTREAM IN ADVANCE OF NEXT
SOUTHERN STREAM SYSTEM AND APPROACHING COLD FRONT LIKELY TO SPREAD
ANOTHER DECK OF STRATOCUMULUS IN 3-5 THOUSAND FOOT RANGE INTO
SOUTHEASTERN WV TERMINAL FORECAST SITES BY/AROUND 08Z/3AM...AND TO
SITES EAST OF THE BLUE RIDGE BEFORE 13Z/9AM.
FURTHER NW...A SLOW MOVING FRONTAL SYSTEM/BAROCLINIC ZONE WAS
SINKING SOUTHEASTWARD THROUGH THE OH VALLEY. GIVEN THAT THE FLOW
ALOFT IS NEARLY PARALLEL TO THE FRONTAL BOUNDARY...EXPECT ONLY
SLOW PROGRESS TO THE SE WITH THE FRONT FOR THE REST OF TONIGHT...
WITH PCPN HOLDING OFF UNTIL WELL AFT DAYBREAK.
WHEN THE PCPN ARRIVES...LOW- LEVEL THICKNESS VALUES WELL ABOVE
THE CRITICAL 1310DM VALUE...SO ALL PCPN SHOULD BE LIQUID...NAMELY
-SHRA. THIS SHOULD OCCUR MAINLY AFT 21Z/4PM ACROSS THE SE WV SITES...
AND NOT UNTIL AFTER THE TERMINAL FORECAST PERIOD ELSEWHERE.
FLIGHT CONDITIONS EXPECTED TO WORSEN TO MVFR TO IFR DUE TO
RESTRICTIONS TO BOTH CEILING AND VSBY AS WIDESPREAD RAIN
OVERSPREADS THE ENTIRE AREA...MAINLY AFTER 06Z/1AM MONDAY...
CONTINUING THROUGH MUCH OF MONDAY MORNING BEFORE GRADUALLY
IMPROVING MONDAY AFTERNOON AS SYSTEM PASSES OFF TO THE EAST OF THE
AREA. PRECIPITATION MAY POSSIBLY MIX WITH OR CHANGE TO SNOW
AND/OR SLEET LATE SUNDAY NIGHT/MONDAY MORNING BEFORE ENDING NORTH
OF A KBLF- KROA- KLYH LINE...WITH GREATEST THREAT CONFINED TO
AREAS NEAR KLWB.
EXTENDED AVIATION DISCUSSION...
HIGH PRESSURE WEDGES SOUTH FROM NEW ENGLAND MONDAY NIGHT INTO
TUESDAY WHICH WILL HOLD COLD AIR NEAR THE SURFACE. MODELS ARE
SHOWING CONSISTENT TRENDS BRINGING WINTER PRECIPITATION INTO THE
AREA BY TUESDAY. A STORM SYSTEM MOVING OUT OF THE GULF COAST
TUESDAY AND INTO THE MID ATLANTIC REGION ON WEDNESDAY WILL PROLONG
THE CHANCE OF PRECIPITATION...AS WELL AS SUB VFR CEILINGS AND
VISIBILITIES. THEN IT DRIES OUT HEADING INTO WED NIGHT-THU WITH
VFR RETURNING. THE NEXT MAJOR SYSTEM WILL AFFECT THE AREA BY NEXT
WEEKEND.
&&
.HYDROLOGY...
AS OF 420 AM EST SUNDAY...
WIDESPREAD RAINFALL IS EXPECTED ACROSS THE AREA TODAY INTO MONDAY
MORNING. ONE HALF TO ONE INCH OF RAINFALL IS LIKELY. WITH THE
GROUND FROZEN SOLID...MUCH OF THIS RAINFALL WILL RUNOFF INTO AREA
RIVERS. AT THIS TIME MODERATE WITHIN BACK RISES ARE EXPECTED ALONG
MAINSTEM RIVERS. WE WILL CONTINUE TO MONITOR THE RAINFALL AND ITS
IMPACT THROUGHOUT THE EVENT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KM
LONG TERM...KM/WP
AVIATION...KM/RAB/WERT/WP
HYDROLOGY...AMS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1052 PM CST SAT FEB 1 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 222 PM CST SAT FEB 1 2014
CONTINUED COLD WITH JUST SOME LIGHT SNOW AND FLURRIES AT TIMES.
THE FLOW ENTERING NOAM HAS BECOME SPLIT...WITH NRN STREAM
DIVERTING ARND STG RIDGE OVER AK AND SRN STREAM UNDERCUTTING THE
RIDGE AND FLOWING INTO CA/NRN MEXICO. A POSITIVELY TILTED UPR TROF
EXTENDED FM HUDSON BAY INTO THE DESERT W. THE STREAMS REMAINED
SEPARATE AS THE ENTERED THE TROF POSN...THEN MERGED BACK TOGETHER
INTO A STG BROAD SWLY FLOW DOWNSTREAM FM THE TROF AXIS...FM THE
SRN PLAINS TO NEW ENGLAND. CHGS TO THE PATTERN DURING THE FCST
PERIOD WL BE SML...WITH PERHAPS THE EXTENSION OF THE TROF IN THE
SWRN CONUS RETROGRADING A LITTLE AND THE SRN STREAM STRENGTHENING
A BIT.
NLY UPR FLOW ACRS WRN CANADA DOWNSTREAM FM THE AK UPR RIDGE WL
ALLOW A COLD ARCTIC ANTICYCLONE TO RIDGE SWD TOWARD THE NRN
PLAINS...RESULTING IN A CONTINUOUS FEED OF COLD AIR INTO THE FCST
AREA. EXPECT TEMPS TO RUN ABOUT 10-18F DEG BLO NORMAL DURING THE
PERIOD. THOUGH THE COLD WON/T BE AS SEVERE AS SOME OF THE PERIODS
IN JANUARY...IT MAY ACTUALLY BE MORE PERSISTENT AS LESS
ROLLERCOASTERING OF TEMPS IS EXPECTED. THE FCST AREA IS LIKELY TO
REMAIN ALONG THE NRN EDGE OF THE PCPN SHIELDS FM SRN STREAM
SYSTEMS...WITH THE BEST FORCING AND MOISTURE PASSING BY TO OUR S.
SO...PCPN AMNTS ARE LIKELY TO END UP BLO NORMAL.
&&
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 222 PM CST SAT FEB 1 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN AREA OF LOW
PRESSURE MOVING ACROSS NORTHERN INDIANA WHILE A REINFORCING ARCTIC
COLD FRONT IS PUSHING INTO WESTERN WISCONSIN. LIGHT SNOW ON THE
NORTHERN EDGE OF THE SURFACE LOW CONTINUES TO IMPACT NORTHEAST
WISCONSIN EARLY THIS AFTERNOON...AND A RECENT UPTICK IN INTENSITY
POSSIBLY SUGGESTS SUPPORT FROM A NORTHERN STREAM SHORTWAVE CURRENTLY
MOVING EAST ACROSS THE ARROWHEAD OF MINNESOTA. STILL THINKING THAT
MOST IF NOT ALL OF THE LIGHT SNOW FROM THIS SYSTEM WILL DEPART BY
THE START OF THE EVENING. CLEARING IS OCCURRING BEHIND THE ARCTIC
FRONT OVER SOUTHERN MINNESOTA...BUT LIGHT SNOW AND FLURRIES IN THE
SMALL COMMA HEAD OVER NE MINNESOTA WILL LIKELY BRUSH N-C WISCONSIN
LATER THIS AFTERNOON INTO EARLY THIS EVENING. SNOW TRENDS AND
TEMPERATURES ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM.
TONIGHT...WEAK AREA OF LOW PRESSURE WILL QUICKLY EXIT TO THE
NORTHEAST OVER THE EASTERN GREAT LAKES. LIGHT SNOW OVER NORTHEAST
WISCONSIN SHOULD HAVE EXITED BY THE START OF THE EVENING. MEANWHILE
A REINFORCING ARCTIC FRONT WILL SLOWLY MOVE EAST ACROSS THE FORECAST
AREA. SOME CLEARING OBSERVED OVER SOUTHERN MINNESOTA AND EASTERN
DAKOTAS SHOULD ARRIVE INTO CENTRAL AND EAST-CENTRAL WISCONSIN AFTER
THE FRONT PASSES. BUT LOW CLOUDS AND FLURRIES OVER NORTHERN
MINNESOTA SHOULD MOVE ACROSS NORTHERN WISCONSIN SO KEPT A CHANCE OF
FLURRIES IN THE FORECAST THROUGH THE EVENING. COLD ADVECTION WILL
TAKE PLACE BEHIND THE ARCTIC FRONT AND WINDS LOOK MARGINAL FOR
DECOUPLING. COMBINED WITH UNCERTAINTIES WITH CLOUD COVER...THIS
MAKES FOR ANOTHER DIFFICULT TEMP FORECAST. LIKE THE PREVIOUS
FORECAST...WILL SHOW COLDER TEMPS OVER CENTRAL WISCONSIN WHERE THE
BEST CHANCE OF CLEARING WILL OCCUR. BUT IF WINDS DROP OFF...TEMPS
COULD TANK LIKE LAST NIGHT. WILL STAY CONSERVATIVE WITH TEMPS
ACROSS THE EAST WHERE CLOUDS WILL CLEAR LAST. WIND CHILLS MAY STILL
APPROACH ADVISORY CRITERIA FOR A FEW HOURS OVER CENTRAL WISCONSIN
LATE TONIGHT ASSUMING WINDS DO NOT BECOME CALM.
SUNDAY...SURFACE RIDGE AXIS ORIGINATING FROM AN ARCTIC HIGH CENTERED
ACROSS THE CENTRAL PLAINS WILL SHIFT EAST ACROSS THE NORTHERN
MISSISSIPPI VALLEY AND WESTERN GREAT LAKES. THIS RIDGE AXIS SHOULD
PROVIDE A COLD BUT QUIET DAY WITH MOSTLY SUNNY TO PARTLY CLOUDY
CONDITIONS PRESENT. WENT WITH A COMBO OF ECMWF GUIDANCE AND
ALLBLEND FOR HIGHS...WHICH WILL RANGE FROM THE MIDDLE SINGLE DIGITS
TO THE LOWER TEENS ABOVE ZERO. THESE TEMPS WILL BE ABOUT 15 DEGREES
BELOW THE AVERAGE FOR THIS DATE.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 222 PM CST SAT FEB 1 2014
WITH LITTLE CHG TO THE LARGE SCALE PATTERN ANTICIPATED...LAST
NIGHT WAS A GOOD INDICATOR OF THE PITFALLS OF THE NIGHTTIME TEMP
FCSTS. SINCE THE CORE OF THE COLD WL REMAIN TO OUR NW...TEMPS WL
DEPEND ON CLDS AND WINDS. ONCE THE CLDS DISSIPATED AND WIND WENT
CALM LAST NGT...TEMPS ABSOLUTELY TANKED AND ENDED UP NEARLY AS
COLD AS LAST WEEK WHEN THE CORE OF THE COLD WAS DIRECTLY OVER THE
AREA. /OF COURSE...WINDS AND HENCE WIND CHILLS WERE NOT NEARLY AS
LOW THIS TIME ARND./ TRENDED TEMPS DOWN A BIT AT TIMES WHEN IT
LOOKED LIKE THERE COULD BE CLR PERIODS AT NGT. OTHERWISE...STAYED
CLOSE TO BLEND OF TOP PERFORMING GUIDANCE.
PRECIP-WISE...THE M.O. OF THE PAST COUPLE SYSTEMS HAS BEEN FOR
EACH TO LOOK LIKE A BETTER PCPN PRODUCER THAN IT/S PREDECESSOR
WHEN VIEWED FM A FEW DAYS OUT...ONLY TO END UP WITH A SWD SHIFT IN
THE PCPN ON THE MODEL RUNS LEADING UP TO THE EVENT. DESPITE SOME
EARLY MODEL RUNS INDICATING NEAR ADVISORY CRITERIA SNOW TDA IN E-C
WI...WE ARE ENDING UP WITH PRETTY MUCH A NUISANCE EVENT. NOW THE
TUE-WED SYSTEM LOOKS TO BE TRACKING A LITTLE FARTHER S AS
WELL...WITH THE SYSTEM NEXT WEEKEND LOOKING LIKE A BETTER PCPN
PRODUCER. HAVE TO WONDER IF LATER EVENTS WILL END UP PRIMARILY
BYPASSING THE AREA TO THE S AS WELL. AS SUCH...USED NOTHING MORE
THAN CHC POPS IN THE LONG-TERM PART OF THE FCST.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1052 PM CST SAT FEB 1 2014
HIGH PRESSURE WILL GRADUALLY BUILD INTO THE FORECAST AREA
OVERNIGHT AND SUNDAY. STILL SOME BKN MVFR CIGS LINGERING OVER
NORTH CENTRAL WISCONSIN. MVFR CIGS SHOULD SLOWLY BEGIN TO MOVE OUT
OF THIS AREA AFTER 09Z FOLLOWED BY VFR CIGS THROUGH THE REMAINDER
OF THE TAF PERIOD.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......ESB
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1008 AM EST SUN FEB 2 2014
.SYNOPSIS...
A COLD FRONT MOVES THROUGH THE TRI-STATE TODAY. AN AREA OF LOW
PRESSURE TRACKS ACROSS THE SOUTHEASTERN STATES TONIGHT...MOVES
SOUTH OF LONG ISLAND MONDAY...THEN EXITS TO THE EAST MONDAY
EVENING. HIGH PRESSURE THEN BUILDS BACK THROUGH TUESDAY. ANOTHER
LOW PRESSURE SYSTEM WILL BRING WINTRY WEATHER TO THE AREA TUE
NIGHT INTO WEDNESDAY WITH POSSIBLY ANOTHER NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CONTINUE TO TIME FOG BASED ON LATEST HRRR AND NARRE. IMPROVEMENT
IS NOTED IN OBS...AND HAVE DROPPED THE DENSE FOG ADV FOR LAND
AREAS. PATCHY DENSE FOG STILL POSSIBLE OVER THE TWIN FORKS AND SE
CT...BUT IMPROVEMENT IS EXPECTED.
OTHERWISE CLOUDS INCREASE FROM THE WEST ALONG AND BEHIND THE COLD
FRONT. HAVE MAINLY SLIGHT CHANCE POPS FOR -SHRA WITH THE FRONT
ACROSS MOST OF NYC/NE NJ/LOWER HUDSON VALLEY...EXCEPT FOR CHANCE
POPS FAR N/W ORANGE COUNTY. APPEARS WITH BEST FORCING WELL TO THE
N/W...THAT LONG ISLAND SHOULD STAY DRY.
KEPT HIGH TEMPS CLOSE TO PREVIOUS...SUPPORTING BY HOURLY MOS
GUIDANCE. EXPECT HIGHS TO BE AROUND 10 DEGREES ABOVE NORMAL - MAINLY
IN THE MID-UPPER 40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
STILL QUITE A BIT OF UNCERTAINTY FOR THE SHORT TERM - WITH THE
REGION BEING ON THE NORTHERN EDGE OF A COASTAL LOW FORECAST TO
PASS 225-250 MILES SE OF KMTP OR ABOUT 125-150 MILES S OF THE
40N/70W BENCH MARK BY 00Z MONDAY.
THE MODELS DO AGREE THAT IN GENERAL A SOUTHERN STREAM SHORTWAVE
CURRENTLY OVER THE DESERT SW TRACKS E AND DEVELOPS A LOW OVER THE
CENTRAL GULF COAST BY 00Z MONDAY. THIS LOW THEN TRACKS NORTHEAST
AS THE SHORTWAVE LIFTS NORTHEAST SUNDAY NIGHT AND MONDAY TO A
POSITION OVER THE TRI-STATE BY 00Z TUESDAY.
THE MODELS ARE ALSO FAIRLY SIMILAR IN THEIR LOW LEVEL THERMAL
FIELDS...SUGGESTING PRECIPITATION STARTS OUT AS A WINTRY MIX LATE
SUNDAY NIGHT...LIKELY BRIEFLY AS A PERIOD OF ALL RAIN OVER THE NYC
METRO AND LONG ISLAND...BEFORE CHANGING TO ALL SNOW BY MID MORNING
ON MONDAY. THIS WILL BE DUE TO LOW LEVEL NORTHERLY FLOW DRAWING
COLD AIR INTO THE REGION FROM LATE SUNDAY NIGHT THROUGH MONDAY.
AS A RESULT...THE 24 HOUR HIGH FOR MONDAY LIKELY WILL OCCUR DURING
THE EARLY MORNING HOURS AT MOST LOCATIONS...WITH TEMPERATURES
DURING THE DAY ON MONDAY HOLDING FAIRLY STEADY FROM THE UPPER 20S
ACROSS HIGHER ELEVATIONS TO THE LOWER 30S ACROSS COASTAL AREAS.
THIS IS CONSISTENT WITH USING A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES SUNDAY NIGHT...AND ADDING GFS 2-METER
TEMPERATURES TO THE BLEND DURING THE DAY ON MONDAY - AND
SUBTRACTING A DEGREE OR 2 DURING THE DAY ON MONDAY TO ACCOUNT FOR
WET-BULBING/WEIGH TOWARDS THE LOWER GUIDANCE.
THE DIFFERENCES LIE IN THE EXACT TRACK AND STRENGTH OF THE
LOW...AND HENCE EXACTLY HOW MUCH LIQUID EQUIVALENT FALLS ON THE
AREA.
BASED ON ALL THE ABOVE...DO HAVE HIGH CONFIDENCE THAT MOST OF THE
CWA WILL SEE PRECIPITATION FROM LATE SUNDAY NIGHT INTO MONDAY AND
THAT BY MID- MONDAY MORNING MOST IF NOT ALL OF IT WILL BE IN THE
FORM OF SNOW. THE EXCEPTION IS OVER FAR N PORTIONS OF THE TRI-
STATE WHERE CONFIDENCE IN PRECIPITATION FALLING AT ALL IS ONLY
MODERATE. AS A RESULT HAVE HIGH CONFIDENCE IN A MEASURABLE SNOW
FALL FOR ALL BUT FAR N PORTIONS OF THE TRI-STATE WHERE CONFIDENCE
IS ONLY MODERATE.
AS FOR SPECIFIC AMOUNTS...STICKING WITH PREVIOUS IDEA OF 2-4 INCHES
OF SNOW ACROSS NYC/NE NJ/COASTAL CT/S LOWER HUDSON VALLEY/MOST OF
LONG ISLAND WITH 1-2 INCHES OF SNOW ELSEWHERE...INCLUDING FAR
EASTERN PORTIONS OF THE TWIN FORKS...WHERE IT WILL TAKE THE
LONGEST TO CHANGE OVER TO ALL SNOW...AND WHERE THE BOUNDARY LAYER
WILL BE THE WARMEST. THIS IS BASED ON USING HPC FORECASTED QPF AND
USING SURFACE TEMPERATURE BASED SNOW TO LIQUID RATIOS...SO
GENERALLY FALL A TAD SHORT OF 10:1 IN MOST AREAS.
HOWEVER...THERE ARE SOME SOLUTIONS...INCLUDING THE ECMWF/CMC/SREF
WHICH FORECAST 1/2-3/4 INCHES OF QPF OVER LONG ISLAND/NYC WHERE AS
THE NAM AND GFS ONLY HAVE AROUND 1/4 OF AN INCH. THE SREF ENSEMBLE
MEMBERS ARE GENERALLY SPLIT BETWEEN THE NAM/GFS AND THE ECMWF/CMC
CAMPS. GIVEN THIS RANGE OF QPF CONFIDENCE IN ADVISORY LEVEL SNOW
IS ONLY AROUND 40 PERCENT...WITH A 30 PERCENT CHANCE OF WARNING
LEVEL SNOW FALL...ALL 20 PERCENT OF SUB-ADVISORY SNOW...AND A 10
PERCENT CHANCE OF NO SNOW AT ALL. THIS LATTER SOLUTION IS
SUPPORTED IS BY 3-4 SREF ENSEMBLE MEMBERS. BASED ON THIS...WILL
CONTINUE TO HIGHLIGHT THE THREAT FOR SNOW LATE TONIGHT/MONDAY IN
THE HWO - INCLUDING THE MENTION OF A SMALL CHANCE FOR WARNING
LEVEL SNOWS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
00Z NWP MODEL SUITE IS IN GOOD AGREEMENT THROUGH 84 HOURS WITH A
W-SW FLOW ALOFT WITH THE GLOBAL MODELS CONTINUING THIS IDEA THROUGH
THE END OF THE WEEK. AN ACTIVE SOUTHERN STREAM WILL BRING A THREAT
OF A STORM SYSTEM EVERY FEW DAYS.
ANY LINGERING LIGHT SNOW BEHIND MONDAYS SYSTEM WILL COME TO AN END
DURING MON EVE WITH HIGH PRES BUILDING OVER THE AREA THROUGH TUE.
TEMPERATURES DURING THIS TIME WILL BE SLIGHTLY BELOW NORMAL LEVELS
UNDER A NLY FLOW. THE HIGH SLIDES OFFSHORE ON TUE AS MID LEVEL
ENERGY TRACKS THROUGH THE SOUTHERN AND CENTRAL PLAINS. THE SFC LOW
WILL TRACK UP THE WESTERN FLANKS OF THE APPALACHIANS TUE NIGHT
WITH POSSIBLE SECONDARY LOW DEVELOPMENT OFF THE DELMARVA COAST.
THE EC HAS BEEN THE MOST CONSISTENT OVER THE LAST 24 HOURS AND
WHILE THE GFS/EC AND CMC ALL TRACK THE LOW VERY CLOSE/OVER THE 40N
70W BENCHMARK...THE DEVIL REMAINS IN THE DETAILS WITH REGARDS TO
THERMAL PROFILES AND P-TYPES. THE GFS HAS TRENDED COLDER AND
THEREFORE CONFIDENCE HAS BEEN GAINED IN A WINTRY MIX EVENT. A
PORTION OF THE AREA COULD SEE A SIGNIFICANT SNOW...SLEET AND
FREEZING RAIN EVENT AND THUS WILL BE HIGHLIGHTED IN THE HWO.
FOR LATER WEDNESDAY NIGHT...HIGH PRESSURE FROM WESTERN CANADA BUILDS
IN WED NIGHT AND REMAINS THROUGH THE END OF THE WORK WEEK WITH ZONAL
FLOW ALOFT. ECMWF AND CMC ARE IN AGREEMENT WITH THIS BUT GFS DOES
BECOME A LITTLE MORE AMPLIFIED WITH THE NORTHERN STREAM THURSDAY AND
THURSDAY NIGHT WITH A STRONGER HIGH PRESSURE ARE BUILDING IN.
HIGH PRESSURE MOVES EAST OF THE REGION NEXT WEEKEND WITH ANOTHER
LOW APPROACHING FROM THE SOUTH AND WEST. TEMPERATURE PROFILES
APPEAR COLD ENOUGH FOR SNOW TO BE A MAIN PRECIP TYPE.
HOWEVER...WITH UNCERTAINTY AND RUN TO RUN MODEL
FLUCTUATIONS...LIMITED POPS TO 30 PERCENT AT MOST.
TEMPERATURES THROUGH WED WILL BE NEAR TO SLIGHTLY BELOW NORMAL
LEVELS...GIVING WAY TO BELOW NORMAL CONDITIONS FOR THE REMAINDER OF
THE WEEK.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A COLD FRONT WILL MOVE ACROSS THE TERMINALS THIS AFTERNOON INTO
EARLY EVENING. FOG DISSIPATING AND BECOMING MORE PATCHY WITH VFR
EXPECTED ACROSS CITY AND WESTERN TERMINALS. STILL SOME LINGERING
IFR OR BELOW CONDITIONS ACROSS SOME TERMINALS NORTH AND EAST OF
CITY...BUT THESE TOO SHOULD IMPROVE TO VFR BY 16-17Z. THEREAFTER
FOR THE AFTERNOON THROUGH FIRST HALF OF TONIGHT...MAINLY VFR BUT
THERE COULD STILL BE POCKETS OF MVFR IN -SHRA NEAR KSWF.
ANY -RA MIXES WITH AND CHANGES TO -SN AFT 6Z AHEAD OF THE NEXT
SYSTEM AND BECOMES WIDESPREAD. IFR TO POTENTIALLY LIFR/OCCASIONAL VLIFR
SN AFT 12-13Z MON WITH MAIN ACCUMULATIONS BEGINNING.
WSW-W BECOMES NW AFTER COLD FRONTAL PASSAGE AFTN-EARLY EVE. WIND
SPEED BLW 10KT THRU THE 24 HR TAF PERIOD. N WINDS INCREASE 10-15KT
AFT 12Z MON.
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)
KEWR FCSTER COMMENTS: HIGH CONFIDENCE IN VFR FOR REST OF THE DAY.
MODERATE CONFIDENCE IN WINDS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS YELLOW...WHICH IMPLIES
SLANT RANGE VISIBILITY 4-6SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: MODERATE CONFIDENCE IN VFR FOR REST OF THE
DAY. OCCASIONAL MVFR POSSIBLE. WILL HAVE TO MONITOR FOR
POSSIBILITY OF ADVECTION OF STRATUS/FOG LATE THIS AFTERNOON.
MODERATE CONFIDENCE IN WINDS.
KLGA FCSTER COMMENTS: HIGH CONFIDENCE IN VFR FOR REST OF THE DAY.
MODERATE CONFIDENCE IN WINDS.
KTEB FCSTER COMMENTS: HIGH CONFIDENCE IN VFR FOR REST OF THE DAY.
MODERATE CONFIDENCE IN WINDS.
KHPN FCSTER COMMENTS: MODERATE CONFIDENCE IN VFR FOR REST OF THE
DAY. OCCASIONAL MVFR POSSIBLE. MODERATE CONFIDENCE IN WINDS.
KISP FCSTER COMMENTS: MODERATE CONFIDENCE IN VFR FOR REST OF THE
DAY. OCCASIONAL MVFR POSSIBLE. MODERATE CONFIDENCE IN WINDS.
.OUTLOOK FOR 12Z MON THROUGH FRI...
.MONDAY/EARLY MONDAY EVENING...MODERATE SNOW...POSIBLY MIXED WITH
RAIN AT THE COASTS...WITH IFR/LIFR AND OCCASIONAL VLIFR CONDITIONS.
TOTAL SNOW ACCUMULATION 2-4 INCHES AT THE NYC METRO/LONG ISLAND
TERMINALS...AND 1-3 INCHES AT THE CT/LOWER HUDSON VALLEY
TERMINALS.
.LATE MONDAY EVENING-TUESDAY...VFR.
.TUESDAY NIGHT...BECOMING IFR WITH INCREASING CHANCE OF WINTRY
PRECIP.
.WEDNESDAY INTO WEDNESDAY EVENING...IFR EXPECTED. SNOW INLAND AND A
WINTRY MIX AT THE COAST IN THE MORNING...CHANGING TO RAIN AT THE
COAST IN THE AFTERNOON. FREEZING RAIN POSSIBLE AT KSWF/KHPN.
.WEDNESDAY NIGHT-THURSDAY NIGHT...VFR.
.FRIDAY...VFR. SLIGHT CHANCE LIGHT SNOW FRI NIGHT.
&&
.MARINE...
BASED ON NEAR SHORE OBSERVATIONS AND WEB CAMS...VISIBILITIES ARE
LESS THAN 1 MILE ACROSS THE EASTERN WATERS. WILL EXTEND THE DENSE
FOG ADVISORY FOR THOSE LOCATIONS THROUGH 1 PM..BUT IT COLD IMPROVE SOONER.
OTHERWISE THE FORECAST APPEARS ON TRACK.
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
THROUGH MONDAY. A LIGHT PRESSURE GRADIENT OVER THE WATERS WILL
KEEP WINDS 10 KT OR LESS THROUGH THIS EVENING...EXCEPT OVER
ANZ-350 WHERE WINDS UP TO 15 KT ARE EXPECTED MAINLY THIS MORNING.
WINDS DO INCREASE LATE TONIGHT OVER THE COASTAL OCEAN WATERS...AND
ON THE REMAINDER OF THE WATERS ON MONDAY IN RESPONSE TO A COASTAL
LOW PASSING WELL TO THE S...WITH GUSTS TOPPING OUT AT AROUND 20
KT ON MONDAY.
SUB-ADVISORY CONDITIONS ARE EXPECTED MON NIGHT THROUGH TUE NIGHT
AS HIGH PRES BUILDS ACROSS THE AREA. WINDS AND SEAS WILL THEN
INCREASE AS THE PRES GRADIENT TIGHTENS WITH LOW PRES MOVING
THROUGH THE AREA ON WED. SCA CONDITIONS ARE LIKELY ON THE OCEAN
WATERS AND EASTERN LI SOUND/BAYS...WITH A LOW END CHANCE FOR GALE
FORCE WINDS ON THE OCEAN WED NIGHT. SUB-ADVISORY CONDITIONS
EXPECTED ON ALL WATERS BY THU AFTN AND REMAINING THROUGH THU
NIGHT.
&&
.HYDROLOGY...
NO WIDESPREAD SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH THIS
EVENING.
CURRENTLY FORECASTING FROM 0.1-0.4 INCHES OF QPF FROM N TO S FROM
LATE TONIGHT THROUGH MONDAY. HOWEVER THERE IS QUITE A BIT OF
UNCERTAINTY ON AMOUNTS...AND THEY COULD END UP AROUND 1/4-1/3
INCH EITHER HIGHER OR LOWER THAN THOSE AMOUNTS. THIS SHOULD MAINLY
FALL IN THE FORM OF SNOW...SO NO HYDROLOGIC IMPACTS ARE EXPECTED.
THERE IS THE POTENTIAL FOR SIGNIFICANT PRECIPITATION LATE TUE NIGHT
THROUGH WED...HOWEVER THE MAJORITY OF IT WILL LIKELY FALL IN THE
FROZEN OR FREEZING STATE.
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
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...NONE.
NJ...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR ANZ330-
340-345-350.
&&
$$
SYNOPSIS...24/MALOIT
NEAR TERM...MALOIT/PW
SHORT TERM...MALOIT
LONG TERM...24
AVIATION...JMC/JM
MARINE...24/MALOIT/PW
HYDROLOGY...24/MALOIT
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS ALBANY NY
1001 AM EST SUN FEB 2 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS THE REGION TODAY. THIS FRONT WILL
BRING SOME ADDITIONAL SHOWERS OF LIGHT VALLEY RAIN AND MOUNTAIN
SNOW. LITTLE OR NO ADDITIONAL ACCUMULATION IS EXPECTED. A STORM
TRACKING JUST TO OUR SOUTH LOOKS TO BRING A SNOWSTORM TO THE
REGION TUESDAY NIGHT INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1000 AM EST...COLD FRONT CURRENTLY MOVING THROUGH THE
CENTRAL PART OF THE AREA LATE THIS MORNING...AS SURFACE OBS
INDICATE WINDS HAVE SHIFTED TO THE NORTHWEST ACROSS THE WESTERN
ADIRONDACKS AND MOHAWK VALLEY. THE FRONT WILL MOVE THROUGH THE
CAPITAL REGION IN THE NEXT FEW HOURS...THEN AREAS TO THE SOUTH AND
EAST OF ALBANY DURING THE AFTERNOON. TEMPERATURES WILL SPIKE AHEAD
OF THE FRONT...THEN GRADUALLY START DROPPING POST-FROPA. WINDS ARE
NOT TERRIBLY IMPRESSIVE IN WAKE OF THE FRONT...NEITHER IS THE
THERMAL GRADIENT...SO TEMPERATURES WILL NOT DROP ABRUPTLY.
LOCAL HIRES WRF AND HRRR SHOWING THE POTENTIAL FOR SOME SHOWERS TO
BLOSSOM AS THE FRONT PROGRESSES EASTWARD ACROSS THE
AREA...POSSIBLY A RESULT OF ENHANCED LOW LEVEL CONVERGENCE ALONG
WITH SLIGHTLY GREATER MOISTURE. STILL...ONLY EXPECTING SCATTERED
SHOWERS SO WILL CAP POPS AROUND 30-40 PERCENT. TEMP PROFILES
INDICATE HIGHER ELEVATIONS MAY BE COLD ENOUGH FOR A FEW SNOW
SHOWERS WITH ONLY A DUSTING OF ACCUMULATION IN SOME SPOTS. VALLEY
LOCATIONS WILL SEE PRIMARILY LIGHT RAIN SHOWERS.
MILD TEMPERATURES ACROSS THE SOUTHEAST HALF OF THE AREA LATE THIS
MORNING WITH UPPER 30S TO MID 40S...ALTHOUGH TEMPERATURES SHOULD
GRADUALLY EASE BACK INTO THE 30S LATE IN THE DAY. TEMPS ONLY IN
THE UPPER 20S TO LOWER 30S EXPECTED FOR WESTERN AREAS THIS
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
TONIGHT...ANY LEFT OVER TERRAIN ENHANCED SHOWERS WILL END AS THE
FLOW BECOMES VERY ANTICYCLONIC. THE SKY IN MOST PLACES WILL AT LEAST
PARTIALLY CLEAR. THE ONLY EXCEPTION WILL BE IN OUR SOUTHERN
ZONES...WHICH WILL LIKELY HOLD ONTO CLOUDS AS ANOTHER DISTURBANCE
APPROACHES FROM THE SOUTH.
TEMPERATURES...WHILE STILL ABOVE NORMAL BY FEBRUARY STANDARDS...WILL
BE NOTICEABLY COLDER THAN THOSE OF LAST NIGHT. LOOK FOR LOWS
GENERALLY IN THE 20S...EXCEPT TEENS AND EVEN SOME SINGLE NUMBERS IN
OUR NORTHWESTERN SECTIONS.
THE DISTURBANCE WILL ULTIMATELY SLIDE WELL SOUTH OF OUR FORECAST
AREA...BUT THERE IS A CHANCE OF ITS PRECIPITATION COULD BRUSH OUR
EXTREME SOUTHERN AREAS...MAINLY NEAR THE INTERSTATE 84 CORRIDOR ON
SOUTHWARD ON MONDAY. IT LOOKS COLD ENOUGH FOR ALL SNOW IN THE
COLUMN...EVEN IF SURFACE TEMPERATURES WERE TO GET ABOVE FREEZING.
OUR FORECAST IMPLIES A LOW PROBABILITY OF PRECIPITATION WHICH WOULD
ALLOW TEMPERATURES TO REACH IN THE MID 30S ACROSS THE SOUTHERN
AREAS. FURTHER NORTH...HIGHS WILL BE IN THE LOWER 30S IN THE CAPITAL
REGION...20S FURTHER NORTH. THESE VALUES ARE VERY CLOSE TO NORMAL
FOR THIS TIME OF YEAR.
WHILE CLOUDS WILL LIKELY HOLD OVER THE SOUTHERN AREAS...SOME
SUNSHINE IS EXPECTED FROM THE CAPITAL REGION NORTHWARD.
HIGH PRESSURE WILL BUILD IN BY MONDAY NIGHT AND TUESDAY TO PROVIDE A
CONTINUATION OF SEASONABLY COLD WEATHER AND A PARTLY CLOUDY SKY.
LOWS MONDAY NIGHT WILL RANGE FROM ZERO TO 10 ABOVE ACROSS THE
ADIRONDACK PARK TO THE LAKE GEORGE AREA...10 TO 15 SOUTHERN VERMONT
AND MOHAWK VALLEY...MID TO UPPER TEENS ACROSS THE REMAINDER OF THE
REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE POTENTIAL FOR A MODERATE TO HEAVY SNOWFALL CONTINUES TO
EXIST FOR LATE TUESDAY NIGHT THROUGH WEDNESDAY ACROSS EASTERN NEW
YORK AND WESTERN NEW ENGLAND...
EXCEPT FOR THE NAM WHICH HAS THE SURFACE LOW MOVING TO NEAR LAKE
ONTARIO BY WEDNESDAY MORNING (AND HAS BEEN DISCOUNTED FOR NOW)...
THE OTHER MODELS ARE IN GOOD AGREEMENT THAT THE SURFACE LOW AND
EVENTUAL SECONDARY LOW WILL MOVE OFF THE COAST SOMEWHERE ALONG THE
MID ATLANTIC STATES. THIS SHOULD RESULT IN THE AIR OVER THE REGION
BEING COLD ENOUGH FOR ALL SNOW WITH THIS EVENT. OVER THE LAST FEW
MODEL RUNS...THE TREND OF THE MEDIUM RANGE MODELS HAS BEEN TO GET
COLDER. EXPECTING SUBSTANTIAL AND WIDESPREAD OVERRUNNING PCPN WHICH
SHOULD PRODUCE A SIGNIFICANT SNOWFALL ACROSS THE REGION. GENERAL
MODEL CONSENSUS IS THAT ABOUT 6 TO 10 INCHES OF SNOW CAN BE EXPECTED
WITH THIS EVENT BASED ON QPF AMOUNTS THAT ARE GENERALLY UNDER AN
INCH...AND EXPECTED SNOW TO LIQUID RATIOS THAT WILL BE RELATIVELY
WET COMPARED TO RECENT SNOWFALLS (TEN OR TWELVE TO ONE WAS USED TO
GET THE FORECAST SNOW TOTALS). HAVE FORECAST POPS RISING TO
CATEGORICAL AFTER MIDNIGHT TUESDAY NIGHT...AND REMAINING CATEGORICAL
THROUGH WEDNESDAY. LOWS TUESDAY NIGHT WILL BE IN THE MID TEENS TO
MID 20S. HIGHS WEDNESDAY IN THE 20S TO LOWERS 30S.
HIGH PRESSURE BUILDS IN QUICKLY BEHIND THIS SYSTEM WEDNESDAY NIGHT
AS IT HEADS OUT TO SEA. EXPECT COLDER BUT MAINLY DRY WEATHER
THURSDAY THROUGH FRIDAY WITH THE EXCEPTION OF SCATTERED LAKE EFFECT
SNOW SHOWERS ACROSS THE WESTERN ADIRONDACKS. LOWS WEDNESDAY NIGHT
WILL BE IN THE SINGLE DIGITS TO MID TEENS. HIGHS THURSDAY IN THE
UPPER TEENS AND 20S. LOWS THURSDAY NIGHT RANGING FROM THE SINGLE
DIGITS IN MOST PLACES TO A FEW DEGREES BELOW ZERO OVER THE
ADIRONDACKS. HIGHS FRIDAY WILL BE 20 TO 30.
DEPENDING ON THE MODEL...THE NEXT SYSTEM WILL EITHER AFFECT THE
REGION ON SATURDAY OR HOLD OFF UNTIL SUNDAY. TO FAR OUT TO MAKE ANY
DECISIONS AS TO WHICH MODEL IS RIGHT AT THIS TIME...SO WILL JUST
FORECAST A LOW CHANCE OF SNOW FOR SATURDAY FOR NOW. LOWS FRIDAY
NIGHT WILL BE IN THE SINGLE DIGITS TO MID TEENS. HIGHS SATURDAY IN
THE 20S TO LOWER 30S.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AS THE COLD FRONT APPROACHES FROM THE WEST...SHOWERS ALONG IT HAVE
NEARLY DISSIPATED OR BECOME ISOLATED. WILL ONLY INCLUDE VCSH AT THE
TAF SITES THROUGH A PART OF TODAY.
MAINLY VFR CONDITIONS HAVE BEEN FORECAST AT THE KALB/KGFL/KPOU/KPSF
TAF SITES THROUGH THE TAF PERIOD ENDING AT 12Z MONDAY. THE
EXCEPTIONS WILL BE THE POSSIBILITY OF MVFR FOG CONDITIONS AT
KGFL/KPSF FOR A COUPLE OF HOURS AT THE START OF THE TAF PERIOD.
LIGHT SOUTH WINDS WILL OCCUR THIS MORNING AT THE TAF SITES AHEAD OF
THE COLD FRONT. AS THE FRONT MOVES THROUGH LATE THIS MORNING AND
EARLY THIS AFTERNOON WINDS WILL SHIFT TO WESTERLY AT 5 TO 10 KTS
WITH SOME GUSTS TO 15 KTS POSSIBLE. LATE IN THE AFTERNOON AND SUNDAY
NIGHT WINDS WILL BECOME NORTH OR NORTHWEST AND DECREASE TO 8 KTS OR
LESS.
OUTLOOK...
MONDAY THROUGH TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT THROUGH WEDNESDAY : HIGH OPERATION IMPACT. SNOW.
WEDNESDAY NIGHT: MODERATE OPERATION IMPACT. CHANCE OF SHSN.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT FIVE DAYS.
ANY PRECIPITATION TODAY WILL BE LIGHT AND INSIGNIFICANT TO THE WATER
SHEDS. DRY WEATHER TONIGHT THROUGH TUESDAY.
THEN...IT LOOKS AS IF OUR REGION WILL HAVE A SNOWSTORM TUESDAY NIGHT
THROUGH WEDNESDAY...WITH PERHAPS SOME SLEET MIXING TO THE SOUTH OF
THE CAPITAL DISTRICT. INITIALLY THIS SNOWSTORM WILL HAVE NO REAL
IMPACT ON THE WATER SHEDS.
DRY AND COLD WEATHER RETURNS BY THURSDAY.
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...HWJIV/JPV
NEAR TERM...HWJIV/JPV
SHORT TERM...HWJIV
LONG TERM...GJM
AVIATION...GJM
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
749 AM EST SUN FEB 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 453 AM EST SUN FEB 2 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY INTO THE CNTRL CONUS. AN ELONGATED SHORTWAVE TROUGH
FROM SOUTH OF JAMES BAY TO SRN MN BOOSTING 850-700 MB RH AND
INVERSION HEIGHTS TO 5K-6K FT BROUGHT AN INCREASE IN LES ACROSS ERN
LAKE SUPERIOR. THE HEAVIEST SNOW WAS MOVING INTO NRN LUCE COUNTY
WHERE THE WAS THE GREATEST AMOUNT OF OPEN WATER UPSTREAM. FARTHER
WEST...SOME MODERATE NW FLOW LES HAD ALSO DEVELOPED OFFSHORE FROM
MARQUETTE COUNTY WHERE THERE SEEMED TO BE ENOUGH GAPS IN THE ICE
COVER SO THAT LAND BREEZES COULD SUPPORT STRONGER LOW LEVEL CONV.
THE AMOUNT OF ICE COVER OVER WRN LAKE SUPERIOR IS EXTENSIVE ENOUGH
SO THAT ONLY LIGHT SNOW HAD DEVELOPED WITH LIMITED POTENTIAL FOR ANY
ACCUMULATIONS.
TODAY...EXPECT THE NW FLOW LES TO CONTINUE THROUGH THE MORNING WITH THE
POTENTIAL FOR A FEW INCHES OF ACCUMULATION NEAR THE SHORE EAST OF
MUNISING. SNOW AMOUNTS OF AN INCH OR LESS ARE EXPECTED BETWEEN
MARQUETTE AND MUNISING. AS WINDS BACK AND INVERSION HEIGHTS DROP THIS
AFTERNOON...THE LES SHOULD DIMINISH OVER THE NW AND LIFT OFF SHORE
FROM THE NE CWA.
TONIGHT...THE BEST FORCING WITH THE NEXT CLIPPER SHORTWAVE
REMAINS WELL TO THE NORTH OVER NRN ONTARIO. SOME LES WILL BE
POSSIBLE EARLY OVER NE LUCE COUNTY BEFORE WINDS BACK TO THE SW AND
PUSH THE SNOW BANDS OFFSHORE. WITH CLEARING OVERNIGHT...TEMPS WILL
DROP TO 5 BELOW TO 10 BELOW ZERO OVER THE INLAND WEST HALF OF UPPER
MICHIGAN. HOWEVER...WITH LIGHT WINDS ONLY AROUND 5 MPH...WIND CHILLS
WILL NOT BE SIGNFICANT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN FEB 2 2014
MODELS ARE IN GOOD AGREEMENT WITH BENIGN ZONAL FLOW UNTIL WED WHEN
MODEL TO MODEL DISAGREEMENT INCREASES SIGNIFICANTLY...BUT EVEN WITH
THE VARYING SOLUTIONS NO SIGNIFICANT PRECIP IS DEPICTED OVER THE
CWA.
A SYSTEM SIMILAR TO YESTERDAY IS SHOWN MOVING S OF THE CWA TUE INTO
TUE NIGHT...BUT THAT IS NOT EXPECTED TO BRING PRECIP TO THE CWA. THE
00Z/02 NAM IS THE ONLY MODEL FAR ENOUGH N WITH THE SYSTEM TO GIVE
PRECIP CHANCES IN THE CWA...SO THAT WAS CONSIDERED AN
OUTLIER...ESPECIALLY SINCE IT IS AT THE OF THE MODEL RUN. BESIDE
THAT SYSTEM...CONFIDENCE IS VERY LOW ON ANY OTHER SIGNIFICANT
SYSTEMS TO APPROACH THE AREA. WITH LACK OF CONFIDENCE FOR WED
THROUGH SAT AND GOOD AGREEMENT /BUT LACK OF SIGNIFICANT PRECIP/ MON
THROUGH TUE NIGHT...USED A CONSENSUS OF MODEL GUIDANCE FOR THE
FORECAST. TEMPERATURES OVER THE NEXT WEEK ARE EXPECTED TO BE SIMILAR
TO THE LAST WEEK OR SO WITH HIGHS IN THE SINGLE DIGITS AND TEENS
ABOVE ZERO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 748 AM EST SUN FEB 2 2014
MVFR CONDITIONS WITH LIGHT LAKE EFFECT SNOWS CONTINUE OVER THE
WESTERN TAF SITES WHILE LIGHT SNOW SHOWERS LINGER OVER KSAW. EXPECT
THE VERY LIGHT SNOW AT KSAW TO END THIS MORNING WITH A RETURN TO VFR
CONDITIONS THIS MORNING AS DOWNSLOPE NW WINDS AND DRYING INCREASE.
IMPROVING CIGS/VSBY ARE ALSO EXPECTED AT IWD AND FINALLY CMX BY THIS
AFTERNOON. THIS AFTERNOON THROUGH TONIGHT VFR CONDITIONS WILL
PREVAIL.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 453 AM EST SUN FEB 2 2014
A RELATIVELY QUIET PERIOD OF WEATHER IS EXPECTED FOR LAKE SUPERIOR.
GALES ARE NOT EXPECTED OVER THE NEXT SEVERAL DAYS. SOME PERIODS OF
FREEZING SPRAY WILL STILL OCCUR AT TIMES OVER ANY REMAINING OPEN
WATER AREAS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
732 AM CST SUN FEB 2 2014
.UPDATE...
ISSUED AT 728 AM CST SUN FEB 2 2014
WINDS HAVE INCREASED A BIT TO 4 OR 5 MPH WITH AMBIENT TEMPERATURES
AROUND -10F. SO A WIND CHILL ADVISORY IS IN PLACE UNTIL 16Z THIS
MORNING. A CHECK OF THE MESONET SUGGESTS LINCOLN COUNTY IS OKAY
AT THIS POINT WITH CALM WINDS AND TEMPS -5F TO -7F.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST SUN FEB 2 2014
TODAY AND TONIGHT...SOME TRAPPED MOISTURE HAS DEVELOPED IN THE
PLATTE VALLEY THIS MORNING PRODUCING A 100 FT CEILING AT NORTH
PLATTE. THIS THIN VEIL OF MOISTURE...IF IT PERSISTS...SHOULD MIX OUT
AFTER SUNRISE. THE RAP HAS MISPLACED THIS MOISTURE FURTHER NORTH AND
WEST ACROSS THE CHEYENNE DIVIDE OVER THE SRN PANHANDLE. SFC OBS SHOW
THIS MOISTURE FARTHER SOUTH ACROSS NERN COLO. REGARDLESS...THE RAP
MOVES THIS MOISTURE EAST PRESUMABLY THRU SWRN NEB SOUTH OF
INTERSTATE 80. ITS POSSIBLE DENSE FOG MAY DEVELOP ALONG AND SOUTH OF
THE INTERSTATE BEFORE SUNRISE.
WIND CHILL READINGS ARE CLOSE TO -20F ACROSS THE SOUTH. IF WINDS CAN
INCREASE THEN A WIND CHILL ADVISORY WOULD BE NEEDED FOR A FEW HOURS
THIS MORNING.
OTHERWISE...THE ARCTIC HIGH CENTERED OVER THE SNOW FIELD COVERING
SWRN NEB...NRN KS AND ERN NEB IS FCST TO MOVE EAST INTO MO/IL BY
MONDAY MORNING. A WARM FRONT IS FCST TO DEVELOP ACROSS NRN NEB
TONIGHT AHEAD OF A VERY STRONG ARCTIC HIGH RIDGING FROM THE YUKON
SOUTH THROUGH THE NRN HIGH PLAINS. CLEAR SKIES ARE EXPECTED ACROSS
THE FCST AREA TODAY AND TONIGHT SUPPORTING HIGHS IN THE 20S ACROSS
THE SNOW FIELD SOUTH AND 30S ACROSS THE SNOW-FREE NORTH. THE WARM
FRONT SHOULD KEEP THE ATM WELL MIXED TONIGHT AND LOWS FOLLOW IN THE
SINGLE DIGITS SOUTH TO NEAR 10 ABOVE IN THE NORTH. THE MET GUIDANCE
SUGGESTED SUBZERO LOWS TONIGHT ACROSS THE SOUTH BUT THIS HAS BEEN
SET ASIDE FOR NOW. THE GEM REGIONAL MODEL SHOWS LOWS IN THE SINGLE
DIGITS AND THIS MODEL HAS BEEN VERIFYING THE BEST WITH THE ONGOING
TEMPERATURE FORECAST EARLY THIS MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CST SUN FEB 2 2014
12Z MONDAY AND BEYOND. THE FORECAST CONCERNS IN THE EXTENDED
PERIODS ARE BITTERLY COLD TEMPERATURES AND THE POTENTIAL FOR SNOW
LATE MONDAY THROUGH EARLY WEDNESDAY AND POSSIBLY AGAIN LATE WEEK
INTO THE WEEKEND.
MONDAY...THE MODELS ARE CONTINUING TO ADVERTISE MOISTURE RETURN IN
ADVANCE OF A SOUTHERN STREAM TROUGH ADVANCING ACROSS THE
DESERT SOUTHWEST. ISENTROPIC UPGLIDE AND OMEGA ASSOCIATED WITH A
140KT UPPER JET MAY TRIGGER SNOW PRODUCTION BY AFTERNOON...SPREADING
FROM SOUTHWEST TO NORTHEAST NEBRASKA. HOWEVER A BETTER
PRECIPITATION SIGNAL IS SHOWN EARLY ON TUESDAY AS DPVA ASSOCIATED
WITH THE SOUTHERN STREAM WAVE SPREADS EAST NORTHEAST AND EJECTS
ACROSS THE SOUTHERN PLAINS. SNOW IS EXPECTED TO BECOME WIDESPREAD
AFTER DAYLIGHT WITH THE HIGHEST CHANCES REMAINING ALONG OUR SOUTHERN
BORDERS. WILL CONTINUE TO TREND THE POP FORECAST UPWARD WITH THIS
FORECAST PACKAGE...WITH 50-60% POPS ALONG AND SOUTH OF I80 TUESDAY.
DESPITE THE INCREASE IN POPS...WILL NOT VENTURE MUCH HIGHER WITH
EXPECTED QPF AS MODEL CONSENSUS INDICATES ~0.15" ACROSS OUR
SOUTH...AND LESS THAN A TENTH OF AN INCH FOR THE NORTHERN
SANDHILLS. SNOW PRODUCTION WILL BE ABOVE CLIMO NORMS AS PROXIMITY
SOUNDINGS INDICATE A DEEP DENDRITIC GROWTH ZONE...SO DESPITE
SOMEWHAT LIMITED MOISTURE...A FEW INCHES OF SNOW MAY BE POSSIBLE
GIVEN A 15:1 /OR HIGHER/ SLR. FORCING SPREADS TO THE EAST EARLY
WEDNESDAY WITH ONLY LIGHT SNOW REMAINING...WILL LIMIT POPS TO LOW
END CHANCE DURING THE DAY. BEYOND WEDNESDAY PRECIPITATION CHANCES
BECOME LIMITED TO OUR FAR SOUTHWEST WITH THE UPPER LEVELS
TRANSITIONING TO ZONAL. THERE IS HOWEVER A BETTER PRECIPITATION
SIGNAL LATE IN THE WEEK/EARLY NEXT WEEKEND WITH THE DEVELOPMENT OF
THE NEXT WESTERN CONUS TROUGH. BOTH THE EC AND GFS...WITH SUPPORT
FROM THE ENSEMBLES SUPPORT THIS LATE WEEK SYSTEM...THUS SLIGHT
CHANCE POPS ARE WARRANTED FOR NOW.
CONCERNING TEMPERATURES...ARCTIC AIR BEHIND A STRONG COLD FRONT WILL
INFILTRATE THE REGION LATE MONDAY AND REMAIN THROUGH MUCH OF THE
EXTENDED PERIODS. TUESDAY WILL BE MUCH COLDER AS H85 TEMPERATURES
FALL TO MINUS 20 OR COLDER FOR MUCH OF THE REGION. HIGHS SHOULD TOP
OUT ONLY IN THE TEENS...WITH THE POTENTIAL OF SINGLE DIGIT HIGHS FOR
OUR NORTH. COLDER YET FOR WEDNESDAY WITH ALL LOCATIONS ACROSS THE
FORECAST AREA STRUGGLING TO REACH THE UPPER SINGLE DIGITS. HIGHS
THURSDAY AND FRIDAY WILL WARM A FEW DEGREES EACH DAY AS WEAK RETURN
FLOW TRIES TO BECOME ESTABLISHED ACROSS THE HIGH PLAINS. LOWS
WEDNESDAY...THURSDAY AND QUITE POSSIBLY FRIDAY MORNING SHOULD BE
BELOW ZERO AS THE ARCTIC HIGH SETTLES ACROSS THE HIGH PLAINS. NOTE
THAT IF ADDITIONAL FRESH SNOW WERE TO ADD TO THE SNOWPACK...THE
DETERMINISTIC GUIDANCE WOULD BE ANOMALOUSLY TOO WARM...THIS MAY BE A
CASE WHERE SOME LOCATIONS SEE THE COLDEST READINGS OF THE SEASON.
WITH THE BITTERLY COLD TEMPERATURES EXPECTED DURING THE OVERNIGHT
ANY AMOUNT OF WIND WOULD ALLOW FOR CRITICALLY LOW WIND CHILL
READINGS. WIND CHILL ADVISORIES MAY BE NEEDED WEDNESDAY AND
THURSDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 511 AM CST SUN FEB 2 2014
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT.
ARCTIC HIGH PRESSURE WILL MOVE EAST INTO ILLINOIS WITH LOW
PRESSURE FORMING OVER THE CNTL HIGH PLAINS EAST INTO WRN NEB.
GENERALLY CLEAR SKIES ARE EXPECTED ACROSS THE FCST AREA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ THIS MORNING FOR
NEZ038-056-057.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
511 AM CST SUN FEB 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST SUN FEB 2 2014
TODAY AND TONIGHT...SOME TRAPPED MOISTURE HAS DEVELOPED IN THE
PLATTE VALLEY THIS MORNING PRODUCING A 100 FT CEILING AT NORTH
PLATTE. THIS THIN VEIL OF MOISTURE...IF IT PERSISTS...SHOULD MIX OUT
AFTER SUNRISE. THE RAP HAS MISPLACED THIS MOISTURE FURTHER NORTH AND
WEST ACROSS THE CHEYENNE DIVIDE OVER THE SRN PANHANDLE. SFC OBS SHOW
THIS MOISTURE FARTHER SOUTH ACROSS NERN COLO. REGARDLESS...THE RAP
MOVES THIS MOISTURE EAST PRESUMABLY THRU SWRN NEB SOUTH OF
INTERSTATE 80. ITS POSSIBLE DENSE FOG MAY DEVELOP ALONG AND SOUTH OF
THE INTERSTATE BEFORE SUNRISE.
WIND CHILL READINGS ARE CLOSE TO -20F ACROSS THE SOUTH. IF WINDS CAN
INCREASE THEN A WIND CHILL ADVISORY WOULD BE NEEDED FOR A FEW HOURS
THIS MORNING.
OTHERWISE...THE ARCTIC HIGH CENTERED OVER THE SNOW FIELD COVERING
SWRN NEB...NRN KS AND ERN NEB IS FCST TO MOVE EAST INTO MO/IL BY
MONDAY MORNING. A WARM FRONT IS FCST TO DEVELOP ACROSS NRN NEB
TONIGHT AHEAD OF A VERY STRONG ARCTIC HIGH RIDGING FROM THE YUKON
SOUTH THROUGH THE NRN HIGH PLAINS. CLEAR SKIES ARE EXPECTED ACROSS
THE FCST AREA TODAY AND TONIGHT SUPPORTING HIGHS IN THE 20S ACROSS
THE SNOW FIELD SOUTH AND 30S ACROSS THE SNOW-FREE NORTH. THE WARM
FRONT SHOULD KEEP THE ATM WELL MIXED TONIGHT AND LOWS FOLLOW IN THE
SINGLE DIGITS SOUTH TO NEAR 10 ABOVE IN THE NORTH. THE MET GUIDANCE
SUGGESTED SUBZERO LOWS TONIGHT ACROSS THE SOUTH BUT THIS HAS BEEN
SET ASIDE FOR NOW. THE GEM REGIONAL MODEL SHOWS LOWS IN THE SINGLE
DIGITS AND THIS MODEL HAS BEEN VERIFYING THE BEST WITH THE ONGOING
TEMPERATURE FORECAST EARLY THIS MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CST SUN FEB 2 2014
12Z MONDAY AND BEYOND. THE FORECAST CONCERNS IN THE EXTENDED
PERIODS ARE BITTERLY COLD TEMPERATURES AND THE POTENTIAL FOR SNOW
LATE MONDAY THROUGH EARLY WEDNESDAY AND POSSIBLY AGAIN LATE WEEK
INTO THE WEEKEND.
MONDAY...THE MODELS ARE CONTINUING TO ADVERTISE MOISTURE RETURN IN
ADVANCE OF A SOUTHERN STREAM TROUGH ADVANCING ACROSS THE
DESERT SOUTHWEST. ISENTROPIC UPGLIDE AND OMEGA ASSOCIATED WITH A
140KT UPPER JET MAY TRIGGER SNOW PRODUCTION BY AFTERNOON...SPREADING
FROM SOUTHWEST TO NORTHEAST NEBRASKA. HOWEVER A BETTER
PRECIPITATION SIGNAL IS SHOWN EARLY ON TUESDAY AS DPVA ASSOCIATED
WITH THE SOUTHERN STREAM WAVE SPREADS EAST NORTHEAST AND EJECTS
ACROSS THE SOUTHERN PLAINS. SNOW IS EXPECTED TO BECOME WIDESPREAD
AFTER DAYLIGHT WITH THE HIGHEST CHANCES REMAINING ALONG OUR SOUTHERN
BORDERS. WILL CONTINUE TO TREND THE POP FORECAST UPWARD WITH THIS
FORECAST PACKAGE...WITH 50-60% POPS ALONG AND SOUTH OF I80 TUESDAY.
DESPITE THE INCREASE IN POPS...WILL NOT VENTURE MUCH HIGHER WITH
EXPECTED QPF AS MODEL CONSENSUS INDICATES ~0.15" ACROSS OUR
SOUTH...AND LESS THAN A TENTH OF AN INCH FOR THE NORTHERN
SANDHILLS. SNOW PRODUCTION WILL BE ABOVE CLIMO NORMS AS PROXIMITY
SOUNDINGS INDICATE A DEEP DENDRITIC GROWTH ZONE...SO DESPITE
SOMEWHAT LIMITED MOISTURE...A FEW INCHES OF SNOW MAY BE POSSIBLE
GIVEN A 15:1 /OR HIGHER/ SLR. FORCING SPREADS TO THE EAST EARLY
WEDNESDAY WITH ONLY LIGHT SNOW REMAINING...WILL LIMIT POPS TO LOW
END CHANCE DURING THE DAY. BEYOND WEDNESDAY PRECIPITATION CHANCES
BECOME LIMITED TO OUR FAR SOUTHWEST WITH THE UPPER LEVELS
TRANSITIONING TO ZONAL. THERE IS HOWEVER A BETTER PRECIPITATION
SIGNAL LATE IN THE WEEK/EARLY NEXT WEEKEND WITH THE DEVELOPMENT OF
THE NEXT WESTERN CONUS TROUGH. BOTH THE EC AND GFS...WITH SUPPORT
FROM THE ENSEMBLES SUPPORT THIS LATE WEEK SYSTEM...THUS SLIGHT
CHANCE POPS ARE WARRANTED FOR NOW.
CONCERNING TEMPERATURES...ARCTIC AIR BEHIND A STRONG COLD FRONT WILL
INFILTRATE THE REGION LATE MONDAY AND REMAIN THROUGH MUCH OF THE
EXTENDED PERIODS. TUESDAY WILL BE MUCH COLDER AS H85 TEMPERATURES
FALL TO MINUS 20 OR COLDER FOR MUCH OF THE REGION. HIGHS SHOULD TOP
OUT ONLY IN THE TEENS...WITH THE POTENTIAL OF SINGLE DIGIT HIGHS FOR
OUR NORTH. COLDER YET FOR WEDNESDAY WITH ALL LOCATIONS ACROSS THE
FORECAST AREA STRUGGLING TO REACH THE UPPER SINGLE DIGITS. HIGHS
THURSDAY AND FRIDAY WILL WARM A FEW DEGREES EACH DAY AS WEAK RETURN
FLOW TRIES TO BECOME ESTABLISHED ACROSS THE HIGH PLAINS. LOWS
WEDNESDAY...THURSDAY AND QUITE POSSIBLY FRIDAY MORNING SHOULD BE
BELOW ZERO AS THE ARCTIC HIGH SETTLES ACROSS THE HIGH PLAINS. NOTE
THAT IF ADDITIONAL FRESH SNOW WERE TO ADD TO THE SNOWPACK...THE
DETERMINISTIC GUIDANCE WOULD BE ANOMALOUSLY TOO WARM...THIS MAY BE A
CASE WHERE SOME LOCATIONS SEE THE COLDEST READINGS OF THE SEASON.
WITH THE BITTERLY COLD TEMPERATURES EXPECTED DURING THE OVERNIGHT
ANY AMOUNT OF WIND WOULD ALLOW FOR CRITICALLY LOW WIND CHILL
READINGS. WIND CHILL ADVISORIES MAY BE NEEDED WEDNESDAY AND
THURSDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 511 AM CST SUN FEB 2 2014
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT.
ARCTIC HIGH PRESSURE WILL MOVE EAST INTO ILLINOIS WITH LOW
PRESSURE FORMING OVER THE CNTL HIGH PLAINS EAST INTO WRN NEB.
GENERALLY CLEAR SKIES ARE EXPECTED ACROSS THE FCST AREA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
913 AM EST SUN FEB 2 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED FRONT WILL CONTINUE MOVING
ACROSS THE NORTH COUNTRY TODAY BRINGING LIGHT PRECIPITATION TO THE
AREA...TAPERING OFF THIS AFTERNOON. HIGH PRESSURE BUILDS INTO THE
AREA TONIGHT AND REMAINS INTO TUESDAY. THIS WILL BE FOLLOWED BY A
COASTAL SYSTEM AFFECTING THE REGION MIDWEEK...WITH HIGH PRESSURE
RETURNING FOR THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 913 AM EST SUNDAY...MADE SOME WHOLESALE CHANGES TO POPS/WX AS
WE PROGRESS INTO TODAY/TONIGHT BASED OFF CURRENT OBSERVATIONAL
TRENDS. CURRENT ANALYSIS SHOWING SFC FRONT NOW SLOWLY PROGRESSING
SOUTHWARD ACROSS THE FCST AREA...WITH BEST MOISTURE NOW BECOMING
FOCUSED ACROSS THE SRN TIER OF NY INTO CENTRAL/SRN NEW ENGLAND.
FEEL WITH LATEST TRENDS IN THE BTV4 AND RAP PROGS...BEST FOCUS FOR
PCPN SHOULD OCCUR ACROSS OUR SOUTHERN ZONES TODAY...THOUGH CAN`T
RULE OUT SOME SCT LIGHT SPRINKLES/SHSN ACTIVITY ACROSS THE NORTH
AS NORTHWESTERLY FLOW AND MODEST COLD THERMAL ADVECTION ACT WITH
OROGRAPHIC EFFECTS. IN ALL CASES PCPN WILL BE LIGHT...HOWEVER BEST
SHOT OF ADDL ACCUMULATIONS AGAIN APPEAR TO BE ACROSS THE SOUTH
WHERE A DUSTING TO PERHAPS 2 INCHES WILL BE POSSIBLE...ESP HIGHER
TERRAIN OF THE SOUTHERN GREENS. ELSEWHERE AN INCH OR LESS AND
MAINLY HIGHER ELEV OF THE DACKS/NRN GREENS. WITH SFC FRONT SAGGING
THROUGH THE AREA...TEMPERATURES WILL EITHER HOLD NEARLY STEADY IN
THE CASE OF OUR SOUTHERN COUNTIES...OR GRADUALLY FALL THROUGH THE
DAY FOR CENTRAL/NRN AREAS. BY EARLY EVENING READINGS WILL RANGE
FROM THE UPPER 20S TO LOWER 30S NORTH...AND MID TO UPPER 30S SOUTH
UNDER LIGHT NORTH TO NORTHWESTERLY FLOW AS FRONT WILL HAVE CLEARED
SOUTH.
BY TONIGHT ANY LINGERING FLURRIES/LIGHT SHSN WILL BE ENDING AS SFC
HIGH PRESSURE GRADUALLY BUILDS EAST FROM SC CANADA/GREAT LAKES.
EXPECT BEST SHOT OF CLEARING TO OCCUR IN THE NORTHERN VALLEY AND
PERHAPS NRN MTNS...WITH AT LEAST SOME LINGERING CLOUD COVER SOUTH.
LOWS BY MONDAY MORNING 5 TO 15 ABOVE NORTH AND HIGHLY DEPENDENT ON
AMT OF CLEARING...AND GENERALLY 10 TO 15 ABOVE SOUTH.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH TUESDAY/...
AS OF 358 AM EST SUNDAY...FOR MONDAY THRU TUESDAY...SFC RIDGE WILL
BUILD OVER THE NORTHEAST REGION PROVIDING A NICE 48-HR...PRECIP-
FREE STRETCH. DO EXPECT DAYTIME TEMPS DURING THIS TIMEFRAME TO
REMAIN NEAR NORMAL FOR THIS TIME OF YEAR. CLR SKIES MONDAY NIGHT
WITH LIGHT WINDS WILL GIVE AREA STRONG RADIATIONAL COOLING...SO
WILL GO SLIGHTLY BLW NORMAL BY A DEGREE OR TWO AREA-WIDE.
OVERALL....HIGHS WILL RANGE IN THE 20S WITH SPOTS 30F IN THE
CVLY/LWR CT RIVER VALLEY. OVERNGT LOWS WILL RANGE MAINLY ZERO TO
10 ABV...WITH SOME NEG SINGLE NUMBERS IN THE DACKS AND FAR NE
KINGDOM.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EST SUNDAY...CONTINUE TO SEE GOOD CONSISTENCY BETWEEN
ECMWF AND GFS WITH THE 00Z CYCLE AND BELOW AVERAGE SPREAD IN 00Z
GFS ENSEMBLE MEMBERS KEEPING THE EXTENDED FCST RELATIVELY STABLE.
MAIN ISSUE WILL BE EXPECTED SNOWFALL DEVELOPING BETWEEN 06-12Z
WEDNESDAY AND LASTING THRU THE DAY. SRN STREAM SHORTWAVE TROUGH
EJECTING NEWD ACROSS THE MID-MS AND OHIO VALLEYS DURING TUESDAY
NIGHT WILL BE ASSOCIATED WITH A SFC LOW MOVING NEWD ACROSS THE
CENTRAL APPALACHIANS. THIS SFC LOW IS EXPECTED TO REDEVELOP OFF
THE NJ COAST DURING THE DAY WEDNESDAY...KEEPING LOW-LEVEL NELY TO
NLY FLOW ACROSS THE NORTH COUNTRY. CONTINUES TO APPEAR TO BE AN
ALL SNOW EVENT ACROSS THE REGION BASED ON 00Z ECMWF AND GFS TEMP
PROFILES. WE/VE DISREGARDED THE WARMER 00Z NAM AT THIS
POINT...WHICH TENDS TO HAVE POORER VERIFICATION OF PARENT SYNOPTIC
FEATURES TOWARD 84-HRS. LOW-LEVEL WAA AND QG FORCING ALLOWS SNOW
TO OVERSPREAD THE REGION FROM SW-NE LATE TUESDAY NIGHT...WITH
HEAVIEST QPF/SNOWFALL RATES EXPECTED THRU 18Z WEDNESDAY. 700MB
TROUGH REMAINS AN OPEN WAVE...THUS SYSTEM IS RELATIVELY QUICK
MOVING WITH SNOWFALL TAPERING OFF TO SNOW SHOWERS TOWARD WEDNESDAY
EVENING. GIVEN TRACK OF LOW OFF THE SRN NEW ENGLAND
COAST...ANTICIPATED HEAVIEST SNOWFALL WILL BE ACROSS
CENTRAL/S-CENTRAL VT. MODEL QPF FORECASTS RANGE FROM AROUND 0.25"
NEAR THE INTL BORDER UP TO 0.75" ACROSS SRN RUTLAND/WINDSOR
COUNTIES...WHICH APPEAR REASONABLE BASED ON PW VALUES AND SPEED OF
THE SYSTEM. IF THESE TRENDS HOLD...PROBABLY LOOKING AT A 6-10"
SNOWFALL ACROSS CENTRAL/S-CENTRAL VT WITH GENERALLY 3-6" IN THE
BTV AREA...NRN VT AND THE NORTHERN ADIRONDACKS. MAY SEE A BIT LESS
IN THE IMMEDIATE ST. LAWRENCE VALLEY FURTHEST REMOVED FROM
ANTICIPATED LOW TRACK. MAIN IMPACT WITH THIS SYSTEM WILL BE WITH
SNOW COVERED ROADWAYS AND POTENTIAL SLOW TRAVEL CONDITIONS FROM
THE PRE-DAWN HRS WEDNESDAY RIGHT THRU THE DAYLIGHT HRS. WE/LL
MENTION THIS POTENTIAL SYSTEM ONCE AGAIN IN THE MORNING HAZARDOUS
WEATHER OUTLOOK. HIGH TEMPERATURES ON WEDNESDAY ARE EXPECTED TO
BE IN THE MID-UPR 20S.
SYNOPTIC LOW DEPARTS QUICKLY EWD SOUTH OF NOVA SCOTIA DURING
WEDNESDAY NIGHT. MAY SEE A FEW LINGERING SNOW SHOWERS EARLY FOLLOWED
BY PARTIAL CLEARING DURING THE PRE-DAWN HRS THURSDAY. SFC RIDGE AXIS
WILL BE SHIFTING INTO NRN NY BY 12Z THU...SO MAY SEE SOME GOOD
RADIATIONAL COOLING TOWARD DAWN WITH THE EXPECTED FRESH SNOWPACK.
GENERALLY LOOKING AT LOW TEMPS IN THE SINGLE DIGITS ABOVE ZERO IF
CLEARING OCCURS AS EXPECTED.
GENERALLY FAIR CONDITIONS THU-SAT. A SECONDARY COLD FRONT PASSING
THRU FROM N-S FRIDAY NIGHT MAY BRING A FEW SCATTERED SNOW
SHOWERS...BUT CONDITIONS ARE OTHERWISE EXPECTED TO BE DRY WITH TEMPS
NEAR TO SLIGHTLY BELOW SEASONABLE LEVELS.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
THROUGH 12Z MONDAY...OVC W/ LCL IFR CONDS MSS/SLK TIL 15Z. FEW
FLURRIES/SPRINKLES AS WEAK COLD FRONT SHIFTS THRU THE REGION
AROUND MIDDAY...MAINLY OVER THE MTNS. GENERALLY VFR CIGS ALL TAF
SITES AFT 16Z... EXCEPT LCL MVFR CIGS MPV/SLK. WINDS LIGHT AND
VARIABLE...BECOMING W-NW 5-7 KTS THIS AFTN THRU TONIGHT.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...SFC HIGH PRESSURE WITH LIGHT
WINDS AND DRY CONDITIONS FROM 12Z MONDAY THRU 06Z WEDNESDAY.
GENERALLY VFR THRU THE PERIOD. NEXT LOW PRESSURE SYSTEM TRACKING
NEWD FROM THE TN VALLEY TUESDAY NIGHT WILL REDEVELOP EAST OF NJ
DURING WEDNESDAY MORNING. LOOKING FOR SNOW TO DEVELOP ACROSS OUR
REGION DURING THE PRE-DAWN HOURS WEDNESDAY...AND PERSISTING THRU
THE DAYLIGHT HRS BEFORE TAPERING TO A FEW SNOW SHOWERS WED
EVE/NIGHT. LIGHT TO MODERATE SNOWFALL ACCUMULATION POSSIBLE WITH
IMPACT TO AVIATION GROUND OPERATIONS EXPECTED DURING WEDNESDAY
INTO WEDNESDAY EVENING. GENERALLY IFR 09-22Z WEDNESDAY IN LOW
VSBY/CIGS OWING TO SNOWFALL. IMPROVING BACK TO VFR FOR THURSDAY.
&&
.EQUIPMENT...
AS OF 710 PM EST SATURDAY...THE AUTOMATED SURFACE OBSERVING SYSTEM (ASOS)
AT THE KNAPP STATE AIRPORT IN BARRE-MONTPELIER VERMONT (KMPV) HAS
NOT TRANSMITTED AN OBSERVATION FROM THIS SITE SINCE 1551Z ON
FEBRUARY 1ST. THE FEDERAL AVIATION ADMINISTRATION (FAA) HAS
INFORMED THE NATIONAL WEATHER SERVICE THAT THIS IS DUE A TELEPHONE
COMMUNICATIONS LINE ISSUE. THERE IS NO ESTIMATE AVAILABLE AT THIS
TIME AS TO WHEN SERVICE WILL BE RESTORED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JN
NEAR TERM...JMG
SHORT TERM...JN
LONG TERM...BANACOS
AVIATION...BANACOS
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BUFFALO NY
630 AM EST SUN FEB 2 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL PRODUCE SOME LINGERING LIGHT SNOW
TODAY ESPECIALLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES AND
CENTRAL NEW YORK. THIS WILL END BY THIS EVENING AS HIGH PRESSURE
BUILDS INTO THE REGION. HIGH PRESSURE WILL BRING MAINLY DRY
CONDITIONS MONDAY AND TUESDAY WITH SEASONABLE TEMPERATURES.
WIDESPREAD ACCUMULATING SNOW IS LIKELY TO ARRIVE TUESDAY NIGHT AND
WEDNESDAY AS LOW PRESSURE MOVES FROM THE LOWER OHIO VALLEY TO THE
MID ATLANTIC STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE ANALYSIS SHOWS A WAVY FRONTAL BOUNDARY EXTENDING FROM THE
OHIO VALLEY TO THE SAINT LAWRENCE VALLEY...WITH A WEAK WAVE OF LOW
PRESSURE HEADING INTO SOUTHEAST QUEBEC. IN THE WAKE OF THIS SURFACE
WAVE THE COLD FRONT IS MAKING HEADWAY EAST ACROSS WESTERN NY...
ALLOWING LOW LEVEL COLD ADVECTION TO BEGIN. RADAR IMAGERY SHOWING
WIDESPREAD MAINLY LIGHT PRECIP HAS DIMINISHED AS EXPECTED ACROSS THE
EASTERN PORTION OF THE AREA AND OVER LAKE ONTARIO AS THE FIRST
SURFACE WAVE MOVES AWAY FROM THE REGION. THIS LEAVES AN AREA OF
RETURNS ACROSS THE WESTERN SOUTHERN TIER WHERE STRONGER
FRONTOGENETIC FORCING REMAINS IN PLACE. MOST OF THIS HAS CHANGED
OVER TO WET SNOW AS OF 11Z...ALTHOUGH SOME RAIN IS STILL FOUND
ACROSS SOUTHERN ALLEGANY COUNTY. THIS WILL CHANGE TO SNOW WITHIN THE
NEXT TWO HOURS.
ANOTHER SUBTLE/WEAK BAROCLINIC WAVE MAY RIPPLE ALONG THE FRONTAL
ZONE FROM LATE MORNING THROUGH EARLY TO MID AFTERNOON. THIS IS
SUGGESTED IN THE NAM AND ESPECIALLY THE CANADIAN GEM AND HRRR MODEL
RUNS...WITH A NORTHWARD BULGE IN THE PRECIP SHIELD BRIEFLY. THIS
SEEMS REASONABLE GIVEN BOTH THE GFS AND NAM SHOW ANOTHER MID LEVEL
SHORTWAVE CROSSING THE LOWER LAKES AT THIS TIME...AND HAND 500MB
ANALYSIS VERIFIED THIS FEATURE. WITH THIS IN MIND...HAVE A BRIEF
INCREASE IN POPS AGAIN DURING THE MIDDAY HOURS ESPECIALLY ACROSS THE
SOUTHERN TIER...FINGER LAKES...AND EVENTUALLY THE SOUTHERN TUG HILL
REGION. PRECIP WILL BE ALL SNOW BY THIS TIME. BETWEEN THE LINGERING
MORNING ACTIVITY AND THE SECONDARY WAVE EXPECT LESS THAN AN INCH
ACCUMULATION IN MOST LOCATIONS...WITH 1 TO 2 INCHES FROM THE
SOUTHERN TIER INTO THE HIGHER TERRAIN OF CENTRAL NY.
AS FAR AS HEADLINES GO...THE ADVISORY FOR THE SOUTHERN TIER AND
WESTERN FINGER LAKES WILL REMAIN IN PLACE THROUGH 15Z. THIS WAS
INITIALLY ISSUED DUE TO SOME REPORTS OF ICY ROADS. SURFACE
TEMPERATURES HAVE BEEN WELL ABOVE FREEZING ALL NIGHT...BUT AFTER THE
FRIGID WEATHER THE PAST FEW WEEKS PAVEMENT TEMPERATURES ARE LAGGING
BEHIND. THIS ADVISORY WILL COVER ANY LINGERING ICY SPOTS...AND THE
TRANSITION BACK TO SNOW WHICH MAY PRODUCE ADDITIONAL ICY SPOTS. IF
THE SECONDARY FRONTAL WAVE ENDS UP BEING A LITTLE MORE AGGRESSIVE
SNOWFALL WISE...THIS ADVISORY COULD BE EXTENDED A FEW HOURS TO COVER.
TEMPERATURES WILL REMAIN FAIRLY STEADY TODAY WITH LOW LEVEL COLD
ADVECTION COUNTERACTING THE DIURNAL CYCLE. EXPECT TEMPS IN THE LOWER
30S ACROSS MOST OF THE AREA...WITH SOME LINGERING MID 30S IN CENTRAL
NY.
TONIGHT SURFACE HIGH PRESSURE WILL BUILD INTO THE CENTRAL LAKES AND
SOUTHERN ONTARIO. THIS SHOULD BRING AT LEAST SOME PARTIAL CLEARING
TO THE NORTHERN HALF OF THE REGION...WITH CLOUDS LINGERING CLOSER TO
THE PA STATE LINE WHERE ANOTHER WAVE OF LOW PRESSURE WILL RUN ALONG
THE FRONTAL ZONE AND INTO THE MID ATLANTIC STATES. COLDER AIR WILL
CONTINUE TO FILTER INTO THE REGION...WITH LOWS IN THE TEENS IN MOST
PLACES AND FEW SINGLE DIGITS ACROSS THE NORTH COUNTRY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE LOWER LAKES MONDAY...WHILE
LOW PRESSURE MOVES EAST ACROSS THE MIDDLE ATLANTIC STATES IN THE
MORNING BEFORE SLIDING OFF THE COAST DURING THE AFTERNOON. MOISTURE
ALONG THE NORTHERN FRINGES OF THIS SYSTEM...COMBINED WITH A WEAK
NORTHERLY UPSLOPE FLOW SOUTH OF LAKE ONTARIO...MAY GENERATE
SCATTERED FLURRIES ACROSS THE SOUTHERN TIER IN THE MORNING.
OTHERWISE...WE SHOULD SEE MOSTLY SUNNY SKIES AS THE HIGH BUILDS OVER
NEW YORK STATE DURING THE AFTERNOON. EXPECT MORE CLEARING MONDAY
NIGHT AND EARLY TUESDAY...THEN AN INCREASE IN CLOUDS AS THE NEXT
STORM SYSTEM TAKES SHAPE ACROSS THE NATION`S INTERIOR.
AS THE SURFACE HIGH SHIFTS EAST INTO NEW ENGLAND ON TUESDAY...LOW
PRESSURE WILL MOVE NORTH FROM THE GULF COAST STATES AND REACH THE
THE TENNESSEE VALLEY DURING THE AFTERNOON. THE PRECIPITATION
ASSOCIATED WITH THE LOW AND ITS ASSOCIATED INVERTED TROUGH WILL STAY
MAINLY SOUTH OF NEW YORK STATE...BUT CLOUDS WILL INCREASE FROM SOUTH
TO NORTH THROUGH THE DAY. AS THE LOW LIFTS NORTH TOWARD WESTERN PA
TUESDAY NIGHT...SNOW WILL SPREAD NORTH ACROSS OUR AREA FAIRLY
QUICKLY. THE GFS AND ECMWF DEPICT AN ENERGETIC WARM ADVECTION
PATTERN LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING...BUT THE
BOUNDARY LAYER WILL STAY COLD ENOUGH FOR ALL SNOW.
SUBTLE MODEL DIFFERENCES REGARDING THE PATH OF THE LOW CONTINUE TO
SHOW UP FOR WEDNESDAY. THE ECMWF MAINTAINS THE INTEGRITY OF THE
WESTERN PA LOW INTO WEDNESDAY MORNING BEFORE SHIFTING THE ENERGY TO
A LOW THAT WILL BE PASSING SOUTH OF THE SOUTHERN NEW ENGLAND COAST
DURING THE AFTERNOON. THE GFS TRANSFER THE ENERGY TO THE COASTAL LOW
SOONER. THE NAM REMAINS AN OUTLIER BY TRACKING THE MAIN CENTER OF
THE LOW MUCH FARTHER TO THE NORTH.
OVERALL...IT STILL LOOKS LIKE THE BIGGEST IMPACT FROM THIS SYSTEM IN
TERMS OF SNOWFALL WILL BE FELT ACROSS PA AND SOUTH CENTRAL NEW YORK.
HOWEVER...THE PROJECTED PATH OF THE 850 MB LOW STILL LOOKS FAVORABLE
FOR SOME ACCUMULATING SNOW ACROSS OUR ENTIRE CWA...WITH ADVISORY
TYPE ACCUMULATIONS POSSIBLE ACROSS THE SOUTHERN TIER AND UPPER
GENESEE VALLEY TUESDAY NIGHT INTO WEDNESDAY. FOR NOW...WILL CONTINUE
TO HIGHLIGHT THE POTENTIAL FOR A WIDESPREAD SNOW IN THE HWO AND WAIT
FOR LATER MODEL RUNS TO FINE TUNE THE DETAILS.
A NORTHWEST FLOW OF COLDER AIR BEHIND THE LOW WILL SET THE STAGE FOR
SOME LAKE ENHANCED SNOW SOUTHEAST OF LAKE ONTARIO WEDNESDAY
AFTERNOON. A DECREASE IN SYNOPTIC SCALE MOISTURE WILL CAUSE THE LAKE
EFFECT SNOW TO DIMINISH SOMEWHAT WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
HIGH PRESSURE BUILDS BACK ACROSS THE REGION FOR THE REMAINDER OF THE
WEEK WITH A DEEPER MID CONTINENT TROUGH DEVELOPING NEXT WEEKEND.
ASIDE FROM SOME SNOW THAT MAY LINGER EAST OF LAKE ONTARIO...EXPECT
MAINLY DRY WEATHER TO PREVAIL THURSDAY AND FRIDAY. LOW PRESSURE
MOVING EAST FROM THE OHIO VALLEY WILL BRING A CHANCE FOR LIGHT SNOW
FRIDAY NIGHT INTO SATURDAY. A CHANCE FOR SNOW WILL CONTINUE INTO
SUNDAY AS THIS LOW SETTLES OFF THE EAST COAST.
HIGH TEMPERATURES THURSDAY AND FRIDAY WILL RANGE FROM THE MID TEENS
TO LOWER 20S. SOME MODERATION IN TEMPERATURES WILL TAKE PLACE
SATURDAY. EXPECT LOWS IN THE SINGLE NUMBERS THURSDAY AND FRIDAY
NIGHTS...WITH SOME BELOW ZERO READINGS OVER THE NORTH COUNTRY
THURSDAY NIGHT.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A COLD FRONT WILL CONTINUE TO SAG SLOWLY SOUTHEAST AWAY FROM THE
AREA THIS MORNING. LIGHT SNOW WILL LINGER BEHIND THE FRONT...
ESPECIALLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES THROUGH
EARLY AFTERNOON INCLUDING KJHW. THIS WILL PRODUCE AREAS OF MVFR/IFR
VSBY. A FEW LIGHT FLURRIES MAY REACH AS FAR NORTH AS KBUF-KIAG-KROC
THROUGH MIDDAY WITH SOME LIGHT BR ADDING TO MVFR VSBY AT TIMES.
FAIRLY WIDESPREAD IFR CIGS WILL ALSO CONTINUE TO THE NORTH OF THE
FRONTAL BOUNDARY THROUGH MIDDAY BEFORE SLOW IMPROVEMENT DURING THE
AFTERNOON THROUGH THE MVFR CATEGORY.
THE SNOW WILL END THIS AFTERNOON...AND CIGS WILL FINALLY IMPROVE AND
SCATTER OUT THIS EVENING AS LOW LEVEL MOISTURE ERODES. THIS SHOULD
ALLOW MOST LOCATIONS TO IMPROVE TO VFR.
OUTLOOK...
MONDAY AND TUESDAY...VFR.
TUESDAY NIGHT AND WEDNESDAY...WIDESPREAD IFR IN SNOW.
THURSDAY...MAINLY VFR.
&&
.MARINE...
A COLD FRONT WILL PUSH SLOWLY SOUTHEAST OF THE AREA TODAY WITH
NORTHWEST FLOW INCREASING ON LAKE ONTARIO DURING THE LATE AFTERNOON
AND EVENING. THIS WILL PRODUCE MARGINAL SMALL CRAFT ADVISORY
CONDITIONS AT THE SOUTHEAST CORNER OF THE LAKE. LATER TONIGHT HIGH
PRESSURE WILL BUILD INTO THE LOWER LAKES AND REMAIN IN PLACE MONDAY
AND TUESDAY WITH A RARE PERIOD OF LIGHT WINDS IN MID WINTER. BY
TUESDAY NIGHT AND WEDNESDAY LOW PRESSURE WILL MOVE FROM THE LOWER
OHIO VALLEY TO THE MID ATLANTIC STATES...WITH INCREASING NORTH TO
NORTHEAST WINDS ON THE LOWER LAKES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NYZ012>014-019>021-085.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EST
MONDAY FOR LOZ043-044.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1058 AM EST SUN FEB 2 2014
.SYNOPSIS...
A WARMING TREND TODAY WILL CONTINUE INTO MONDAY AS HIGH PRESSURE
SLIDES OFFSHORE. WEAK LOW PRESSURE WILL PASS NORTHWEST OF THE AREA
EARLY MONDAY. THIS LOW WILL DRAG A COLD FRONT ACROSS THE EASTERN
CAROLINAS MONDAY AFTERNOON. BEHIND THE FRONT HIGH PRESSURE WILL
BUILD DOWN THE COAST THROUGH TUESDAY. A STRONG COLD FRONT WILL
CROSS THE AREA WEDNESDAY NIGHT. COOL AND DRY HIGH PRESSURE WILL
BUILD IN THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1010 AM SUNDAY...FOG AND LOW CLOUDS SLOW TO DISPERSE. MOIST
AIR MASS OVER COLD GROUNDS AND CALM WINDS HAS ALLOWED THE FOG AND
LOW STRATUS DECK TO PERSIST THRU THE LATE MORNING HRS...AND MAY
TAKE UNTIL THE EARLY AFTERNOON AS INCREASING SW-W WINDS FINALLY
MATERIALIZE AT THE SFC. SEA FOG HAS YET TO FULLY MATERIALIZE DUE TO
THE DELAY OF THE MILDER 60+ DEWPOINTS ADVECTING ACROSS THE
COASTAL WATERS WHERE SSTS ARE IN THE 40S. VIA VISIBLE SAT IMAGERY
AND SFC OBS...THE COASTAL COUNTIES HAVE BROKEN OUT FROM THE LOW
CLOUDS AND FOG. THE DAYS INSOLATION HAS ALREADY PUSHED SFC TEMPS
WELL UP INTO THE 50S. AS A RESULT...MAX TEMPS WILL BE RE-ALIGNED
WITH LOW TO MID 60S BECOMING MORE WIDESPREAD. HAVE UPPED MAX TEMPS
ALONG THE IMMEDIATE COAST DUE TO THE DELAY OF THE SEA FOG
MATERIALIZING AND PARTIALLY PUSHING ONSHORE.
PREVIOUS DISCUSSION.............................................
AS OF 630 AM SUNDAY...A 500 MB RIDGE WILL REMAIN PARKED OFF THE SE
COAST WHILE A SHORTWAVE CURRENTLY IN WEST TEXAS MOVES INTO THE
SOUTHERN APPALACHIANS LATE TONIGHT. HERE AT THE SURFACE THE OLD
ARCTIC FRONT THAT BROUGHT US COLD AND ICE LAST WEEK STALLED DOWN
OVER THE BAHAMAS FOR SEVERAL DAYS...BUT HAS RETURNED NORTH TO A
POSITION ABOUT 50-70 MILES OFF THE CAROLINA COAST. THIS BOUNDARY
WILL DISSIPATE LATER TODAY AS SOUTHWEST LOW-LEVEL FLOW STRENGTHENS
BETWEEN THE HIGH WELL OFFSHORE AND AN APPROACHING COLD FRONT FROM
THE NORTHWEST.
A COOL AND COMPLETELY SATURATED LOW-LEVEL AIRMASS HAS PRODUCED
PLENTY OF FOG AND LOW STRATUS THIS MORNING. MODEL FORECAST SOUNDINGS
INDICATE THE TOP OF THIS CLOUD DECK RANGES FROM 2000 FT AGL INLAND
TO NEARLY 10000 FT OVER ILM...BUT SHOULD THIN FROM THE TOP DOWN AS
THE DAY PROGRESSES. TIMING THE BREAKUP OF THESE LOW CLOUDS IS GOING
TO BE KEY TO GETTING CLOSE WITH HIGH TEMPERATURES TODAY. WITHOUT
CLOUDS THE AIRMASS ALOFT IS CAPABLE OF SUPPORTING HIGHS IN THE LOWER
70S QUITE EASILY. BEYOND 11:00 AM EVERY HOUR WE CAN MAINTAIN LOW
CLOUD COVER WILL CUT A COUPLE DEGREES OFF THAT POTENTIAL. I AM
TENTATIVELY FORECASTING HIGHS TO REACH 60-65 TODAY (WARMEST SOUTH OF
FLORENCE AND CONWAY) BUT WITH LOW CONFIDENCE. 06Z MODELS CONTINUE TO
SHOW THE SAME DIFFERENCES AS THEIR 00Z COUNTERPARTS WITH THE GFS
WARM AND NAM AND RUC MUCH COOLER. AS LIGHT WEST-NORTHWEST SURFACE
WINDS BECOME SOUTHWESTERLY LATE THIS MORNING...DEWPOINTS SHOULD
INCREASE ACROSS THE COASTAL WATERS WITH SEA FOG BECOMING MORE
PREVALENT. FOR AREAS WHERE A SOUTHWEST WIND IS ONSHORE (NE HORRY AND
BRUNSWICK COUNTIES) THIS MEANS CLOUDS AND FOG COULD PERSIST ALL
AFTERNOON WITH HIGHS PERHAPS STRUGGLING TO REACH THE MID 50S.
PLENTY OF LOW-LEVEL MOISTURE AND INITIALLY LIGHT WINDS TONIGHT
SHOULD ALLOW FOG AND LOW STRATUS TO REDEVELOP QUICKLY DURING THE
EVENING HOURS. THE APPROACHING SHORTWAVE DISTURBANCE COULD BRING
SCATTERED SHOWERS OR EVEN A THUNDERSTORM ACROSS THE NORTHERN
SECTIONS OF THE PEE DEE REGION LATE TONIGHT...MAINLY NORTH OF
FLORENCE AND MARION. THE REMAINDER OF THE AREA SHOULD REMAIN DRY.
LOWS SHOULD FALL TO 48-53...WARMEST NEAR THE SANTEE RIVER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...WEAK SURFACE WAVE PASSING WEST OF THE AREA
DURING MON WILL DRAG A COLD FRONT ACROSS THE EASTERN CAROLINAS LATE
IN THE DAY. AHEAD OF THE FRONT INCREASED MOISTURE AND DIURNAL
INSTABILITY WILL CREATE POTENTIAL FOR ISOLATED AFTERNOON SHOWERS.
ALTHOUGH LOW LEVEL JET DOES NOT APPEAR STRONG ENOUGH FOR SEVERE
WEATHER IT WILL ENHANCE BOUNDARY LAYER MOISTURE AND INSTABILITY.
FRONT PUSHES OFF THE COAST BY EARLY EVENING WITH HIGH PRESSURE
CENTERED OVER THE GREAT LAKES BUILDING SOUTH. COLD PUSH BEHIND THE
FRONT IS RATHER WEAK AND SURFACE BOUNDARY QUICKLY ENDS UP PARALLEL
TO STEERING FLOW. WEAK ISENTROPIC LIFT DEVELOPS AROUND MIDNIGHT AND
SLOWLY STRENGTHENS OVERNIGHT. ABUNDANT LOW LEVEL MOISTURE AND
AFOREMENTIONED ISENTROPIC LIFT RESULT IN LIGHT RAIN DEVELOPING OVER
THE AREA BY DAYBREAK TUE.
TUE WILL BE DOMINATED BY HIGH PRESSURE WEDGING DOWN THE COAST FROM
THE NORTHEAST. ISENTROPIC LIFT AND INCREASING MOISTURE WILL MAINTAIN
LOW OVERCAST AND INCREASE RAIN CHANCES DURING THE DAY. MEANWHILE
DURING THE DAY TUE A SOUTHERN STREAM SYSTEM EMERGING FROM THE
SOUTHWEST TRACKS NORTHEAST ACROSS THE LOWER MS VALLEY AND INTO THE
TN VALLEY TUE EVENING. AS THE SURFACE LOW MOVES INTO THE OH VALLEY
TUE NIGHT IT LIFTS THE STALLED FRONT/TROUGH OFF THE CAROLINA COAST
NORTH AS A WARM FRONT. STRONG WARM ADVECTION DEVELOPS TUE NIGHT WITH
TEMPS LIKELY RISING OVERNIGHT. TUE HIGHS...WHICH WILL END UP BELOW
CLIMO IN MOST PLACES...ARE LIKELY TO OCCUR LATE IN THE DAY. ALSO
WORTH NOTING THAT TUE HIGHS ARE LIKELY TO BE WITHIN A FEW DEGREES OF
TUE NIGHT LOWS. WEAK CONVECTION IS POSSIBLE IN THE WARM SECTOR TUE
NIGHT BUT SURFACE BASED INSTABILITY IS SOMEWHAT LIMITED. STILL THE
PRESENCE OF DEEPER MOISTURE AND INCREASING LOW LEVEL JET WARRANTS
CONTINUATION OF INHERITED CHC POP.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...ONGOING STRONG WARM ADVECTION AS THE PERIOD
BEGINS WILL PUSH TEMPERATURES INTO THE 70S ACROSS MUCH OF THE AREA
WED DESPITE ABUNDANT CLOUD COVER. INSTABILITY AND DEEP MOISTURE
WITHIN THE WARM SECTOR WILL MAINTAIN ELEVATED PRECIP CHANCES THROUGH
THE AFTERNOON HOURS. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS THE
AREA DURING WED BUT A MORE SIGNIFICANT LINE SEEM LIKELY JUST AHEAD
OF A STRONG COLD FRONT CROSSING THE AREA WED AFTERNOON. FORECAST
SOUNDINGS SHOW SOME LOW LEVEL JETTING BUT IT IS ON THE WEAK SIDE. AS
IS USUALLY THE CASE IN THE CAROLINAS IN WINTER CAPE WILL BE LACKING.
RIGHT NOW THE EVENT APPEARS RATHER BENIGN AS FAR AS STRONGER STORMS
GO BUT THIS COULD CHANGE SO WILL CONTINUE TO MONITOR IT.
IMPRESSIVE PERIOD OF COLD ADVECTION BEGINS WED NIGHT BEHIND THE
EXITING FRONT AND CONTINUES INTO THU AFTERNOON BEFORE WEAKENING.
TEMPS WILL DROP NEAR TO SLIGHTLY BELOW CLIMO FOR THE REMAINDER OF
THE PERIOD. HIGH PRESSURE SHIFTS EAST ACROSS THE OH VALLEY INTO THE
MID ATLANTIC REGION...SETTING THE STAGE FOR ANOTHER WEDGE EVENT LATE
IN THE WEEK. AT THE SAME TIME THE NEXT SOUTHERN STREAM SYSTEM EJECTS
FROM THE SOUTHWEST...DEVELOPING LOW PRESSURE OVER THE NORTHERN GULF
OF MEXICO AND TIGHTENING UP THE WEDGE OVER THE EAST COAST.
ISENTROPIC LIFT DEVELOPS AS EARLY AS FRI AND STRENGTHENS SAT. GIVEN
THE PRESENCE OF DEEP MOISTURE WITH THE LIFT WILL INTRODUCE SLIGHT
CHC POP FRI AND INCREASE POP TO LOW CHC FOR SAT.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AS OF 12Z...CURRENT TRENDS ARE HOLDING...WITH NOT MUCH CHANGE TO THE
PRESENT SET OF TAFS. LOOK FOR IFR/LIFR CONDITIONS TO CONTINUE FOR
MUCH OF THE DAY. THERE WILL BE SOME EROSION IN THE CLOUDS DUE TO
SOLAR INSOLATION. THE NAM BELIEVES THERE WILL BE SOME HOLES IN THE
CEILING BY AFTERNOON...HOWEVER THE GFS KEEPS US SOCKED IN THE ENTIRE
DAY. THINK WE WILL SEE SOME BROKEN SKIES THIS AFTERNOON...STILL A
MVFR CEILING. RISING DEWPOINTS AND SOUTHERLY FLOW WILL HELP FEED THE
LOW LEVEL MOISTURE. TONIGHT...ANY MVFR CONDITIONS LEFTOVER WILL
QUICKLY DETERIORATE TO IFR...WITH PERHAPS A BRIEF SHOWER ALONG THE
COAST.
EXTENDED OUTLOOK...SHOWERS LIKELY WITH MVFR/IFR ON MONDAY. IFR CIGS
EXPECTED ON TUESDAY. CHANCE OF SHOWERS AND MVFR/IFR CONDITIONS ON
WEDNESDAY WITH A COLD FRONT. VFR ON THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM SUNDAY...THE SLOWLY DECAYING SFC BOUNDARY JUST
OFFSHORE FROM THE LOCAL WATERS HAS PREVENTED THE 60+ DEWPOINTS
FROM ADVECTING ACROSS THE ILM COASTAL WATERS...AND THUS DELAYING
THE DEVELOPMENT OF WIDESPREAD SEA FOG. LATEST VISIBLE SAT IMAGERY
DOES SHOW SOME FEATURES THAT COULD RESEMBLE SEA FOG. AS A
RESULT...WILL DROP THE AREA COVERAGE OF THE FOG FROM WIDESPREAD TO
AREAS. THE SFC PRESSURE PATTERN AND LOOSE GRADIENT TO YIELD MAINLY
A SSW-SW FLOW AT 10 KT OR LESS THIS AFTERNOON. SIGNIFICANT SEAS OF
3 TO 4 FT WILL CONTINUE...WITH THE 4 FOOTERS MAINLY OUTER WATERS
OFF CAPE FEAR. THE 10-12 SECOND PERIOD...2 TO 3 FOOT ESE-SE
GROUND SWELL...WILL DOMINATE THE SIG. SEAS SPECTRUM. VERY LITTLE
INPUT WILL COME FROM LOCALLY PRODUCED WIND DRIVEN WAVES.
PREVIOUS DISCUSSION.................................................
AS OF 630 AM SUNDAY...A DENSE FOG EVENT IS UNFOLDING AS SOUTHWEST
WINDS BRING RICH MOISTURE IN ACROSS THE VERY COLD NEARSHORE WATERS.
THE PAST FEW WEEKS OF ARCTIC CHILL HAVE TAKEN BEACH WATER
TEMPERATURES DOWN INTO THE MID TO UPPER 40S. THE DENSE FOG ADVISORY
FOR WIDESPREAD VISIBILITIES BELOW ONE MILE WILL REMAIN IN EFFECT
THROUGH MIDNIGHT TONIGHT.
OTHERWISE...A WEAK FRONT STALLED OFFSHORE SHOULD DISSIPATE LATER
TODAY AS THE REGION COMES UNDER THE INFLUENCE OF SOUTHWEST WINDS
AHEAD OF A COLD FRONT APPROACHING FROM THE NORTHWEST. WIND SPEEDS
SHOULD REMAIN 10 KT OR LESS UNTIL AFTER MIDNIGHT WHEN WIND SPEEDS
COULD KICK UP CLOSER TO 15 KT...ESPECIALLY AWAY FROM SHORE. SEAS IN
THE 2-4 FT RANGE ARE EXPECTED THROUGH TONIGHT WITH A GOOD PORTION OF
THAT DUE TO A 10-SECOND SOUTHEAST SWELL.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...SOUTHWEST FLOW AROUND 15 KT MON WILL BECOME
NORTHWEST MON EVENING AS COLD FRONT MOVES ACROSS THE WATERS. THIS
FRONT WILL HAVE SOME COLD ADVECTION WITH IT BUT STRENGTH IS LIMITED
AND INITIALLY SPEEDS WILL BE IN THE 10 TO 15 KT RANGE. GRADIENT
STARTS TO BECOME MORE DEFINED TUE MORNING AS SURFACE HIGH TO THE
NORTH BUILDS DOWN THE EAST COAST. GRADIENT BECOMES MORE DEFINED TUE
AS COASTAL TROUGH SHARPENS AND SURFACE LOW MOVES ACROSS THE LOWER MS
VALLEY. AS A RESULT NORTHEAST FLOW WILL REMAIN A SOLID 15 KT THROUGH
THE END OF THE PERIOD. SEAS WILL RUN 3 TO 5 FT THROUGH THE PERIOD
WITH THE LARGEST CONCENTRATION OF 5 FT SEAS EXPECTED TUE NIGHT.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...STRONG SOUTHWEST FLOW AHEAD OF ADVANCING COLD
FRONT WILL APPROACH 25 KT AT TIMES ON WED. COLD FRONT MOVES ACROSS
THE WATERS WED EVENING WITH STRONG OFFSHORE FLOW DEVELOPING IN ITS
WAKE. COMBINATION OF PINCHED GRADIENT AND COLD ADVECTION WILL KEEP
SPEEDS AROUND 20 KT INTO THU AFTERNOON. SLIGHT REDUCTION IN GRADIENT
AND WANING COLD ADVECTION WILL DROP NORTHEAST FLOW TO A SOLID 15 KT
FOR THE REMAINDER OF THE PERIOD. SEAS BUILD TO 4 TO 6 FT WED AHEAD
OF THE COLD FRONT. SCA SEAS LINGER INTO WED NIGHT BEFORE OFFSHORE
FLOW IS ABLE TO KNOCK SEAS BACK TO 3 TO 5 FT FOR THU AND THU NIGHT.
&&
.TIDES/COASTAL FLOODING...
AS OF 3 AM SUNDAY...WE ARE NOW TWO DAYS PAST THE NEW MOON BUT
UNUSUALLY LOW WATER LEVELS WILL CONTINUE AT LOW TIDE TODAY.
ASTRONOMICAL LOW TIDE WILL OCCUR AROUND 3:15 THIS AFTERNOON AND THE
ETSURGE/ESTOFS CONSENSUS IS FOR WATER LEVELS SOUTH OF CAPE FEAR TO
REACH -1.30 FEET MLLW...WITH LESSER DEPARTURES NORTH OF CAPE FEAR.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ250-252-
254-256.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH/TRA
SHORT TERM...III
LONG TERM...III
AVIATION...DL
TIDES/COASTAL FLOODING...TRA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
622 AM EST SUN FEB 2 2014
.SYNOPSIS...
A WARMING TREND TODAY WILL CONTINUE INTO MONDAY AS HIGH PRESSURE
SLIDES OFFSHORE. WEAK LOW PRESSURE WILL PASS NORTHWEST OF THE AREA
EARLY MONDAY. THIS LOW WILL DRAG A COLD FRONT ACROSS THE EASTERN
CAROLINAS MONDAY AFTERNOON. BEHIND THE FRONT HIGH PRESSURE WILL
BUILD DOWN THE COAST THROUGH TUESDAY. A STRONG COLD FRONT WILL
CROSS THE AREA WEDNESDAY NIGHT. COOL AND DRY HIGH PRESSURE WILL
BUILD IN THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 630 AM SUNDAY...A 500 MB RIDGE WILL REMAIN PARKED OFF THE SE
COAST WHILE A SHORTWAVE CURRENTLY IN WEST TEXAS MOVES INTO THE
SOUTHERN APPALACHIANS LATE TONIGHT. HERE AT THE SURFACE THE OLD
ARCTIC FRONT THAT BROUGHT US COLD AND ICE LAST WEEK STALLED DOWN
OVER THE BAHAMAS FOR SEVERAL DAYS...BUT HAS RETURNED NORTH TO A
POSITION ABOUT 50-70 MILES OFF THE CAROLINA COAST. THIS BOUNDARY
WILL DISSIPATE LATER TODAY AS SOUTHWEST LOW-LEVEL FLOW STRENGTHENS
BETWEEN THE HIGH WELL OFFSHORE AND AN APPROACHING COLD FRONT FROM
THE NORTHWEST.
A COOL AND COMPLETELY SATURATED LOW-LEVEL AIRMASS HAS PRODUCED
PLENTY OF FOG AND LOW STRATUS THIS MORNING. MODEL FORECAST SOUNDINGS
INDICATE THE TOP OF THIS CLOUD DECK RANGES FROM 2000 FT AGL INLAND
TO NEARLY 10000 FT OVER ILM...BUT SHOULD THIN FROM THE TOP DOWN AS
THE DAY PROGRESSES. TIMING THE BREAKUP OF THESE LOW CLOUDS IS GOING
TO BE KEY TO GETTING CLOSE WITH HIGH TEMPERATURES TODAY. WITHOUT
CLOUDS THE AIRMASS ALOFT IS CAPABLE OF SUPPORTING HIGHS IN THE LOWER
70S QUITE EASILY. BEYOND 11:00 AM EVERY HOUR WE CAN MAINTAIN LOW
CLOUD COVER WILL CUT A COUPLE DEGREES OFF THAT POTENTIAL. I AM
TENTATIVELY FORECASTING HIGHS TO REACH 60-65 TODAY (WARMEST SOUTH OF
FLORENCE AND CONWAY) BUT WITH LOW CONFIDENCE. 06Z MODELS CONTINUE TO
SHOW THE SAME DIFFERENCES AS THEIR 00Z COUNTERPARTS WITH THE GFS
WARM AND NAM AND RUC MUCH COOLER. AS LIGHT WEST-NORTHWEST SURFACE
WINDS BECOME SOUTHWESTERLY LATE THIS MORNING...DEWPOINTS SHOULD
INCREASE ACROSS THE COASTAL WATERS WITH SEA FOG BECOMING MORE
PREVALENT. FOR AREAS WHERE A SOUTHWEST WIND IS ONSHORE (NE HORRY AND
BRUNSWICK COUNTIES) THIS MEANS CLOUDS AND FOG COULD PERSIST ALL
AFTERNOON WITH HIGHS PERHAPS STRUGGLING TO REACH THE MID 50S.
PLENTY OF LOW-LEVEL MOISTURE AND INITIALLY LIGHT WINDS TONIGHT
SHOULD ALLOW FOG AND LOW STRATUS TO REDEVELOP QUICKLY DURING THE
EVENING HOURS. THE APPROACHING SHORTWAVE DISTURBANCE COULD BRING
SCATTERED SHOWERS OR EVEN A THUNDERSTORM ACROSS THE NORTHERN
SECTIONS OF THE PEE DEE REGION LATE TONIGHT...MAINLY NORTH OF
FLORENCE AND MARION. THE REMAINDER OF THE AREA SHOULD REMAIN DRY.
LOWS SHOULD FALL TO 48-53...WARMEST NEAR THE SANTEE RIVER.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...WEAK SURFACE WAVE PASSING WEST OF THE AREA
DURING MON WILL DRAG A COLD FRONT ACROSS THE EASTERN CAROLINAS LATE
IN THE DAY. AHEAD OF THE FRONT INCREASED MOISTURE AND DIURNAL
INSTABILITY WILL CREATE POTENTIAL FOR ISOLATED AFTERNOON SHOWERS.
ALTHOUGH LOW LEVEL JET DOES NOT APPEAR STRONG ENOUGH FOR SEVERE
WEATHER IT WILL ENHANCE BOUNDARY LAYER MOISTURE AND INSTABILITY.
FRONT PUSHES OFF THE COAST BY EARLY EVENING WITH HIGH PRESSURE
CENTERED OVER THE GREAT LAKES BUILDING SOUTH. COLD PUSH BEHIND THE
FRONT IS RATHER WEAK AND SURFACE BOUNDARY QUICKLY ENDS UP PARALLEL
TO STEERING FLOW. WEAK ISENTROPIC LIFT DEVELOPS AROUND MIDNIGHT AND
SLOWLY STRENGTHENS OVERNIGHT. ABUNDANT LOW LEVEL MOISTURE AND
AFOREMENTIONED ISENTROPIC LIFT RESULT IN LIGHT RAIN DEVELOPING OVER
THE AREA BY DAYBREAK TUE.
TUE WILL BE DOMINATED BY HIGH PRESSURE WEDGING DOWN THE COAST FROM
THE NORTHEAST. ISENTROPIC LIFT AND INCREASING MOISTURE WILL MAINTAIN
LOW OVERCAST AND INCREASE RAIN CHANCES DURING THE DAY. MEANWHILE
DURING THE DAY TUE A SOUTHERN STREAM SYSTEM EMERGING FROM THE
SOUTHWEST TRACKS NORTHEAST ACROSS THE LOWER MS VALLEY AND INTO THE
TN VALLEY TUE EVENING. AS THE SURFACE LOW MOVES INTO THE OH VALLEY
TUE NIGHT IT LIFTS THE STALLED FRONT/TROUGH OFF THE CAROLINA COAST
NORTH AS A WARM FRONT. STRONG WARM ADVECTION DEVELOPS TUE NIGHT WITH
TEMPS LIKELY RISING OVERNIGHT. TUE HIGHS...WHICH WILL END UP BELOW
CLIMO IN MOST PLACES...ARE LIKELY TO OCCUR LATE IN THE DAY. ALSO
WORTH NOTING THAT TUE HIGHS ARE LIKELY TO BE WITHIN A FEW DEGREES OF
TUE NIGHT LOWS. WEAK CONVECTION IS POSSIBLE IN THE WARM SECTOR TUE
NIGHT BUT SURFACE BASED INSTABILITY IS SOMEWHAT LIMITED. STILL THE
PRESENCE OF DEEPER MOISTURE AND INCREASING LOW LEVEL JET WARRANTS
CONTINUATION OF INHERITED CHC POP.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...ONGOING STRONG WARM ADVECTION AS THE PERIOD
BEGINS WILL PUSH TEMPERATURES INTO THE 70S ACROSS MUCH OF THE AREA
WED DESPITE ABUNDANT CLOUD COVER. INSTABILITY AND DEEP MOISTURE
WITHIN THE WARM SECTOR WILL MAINTAIN ELEVATED PRECIP CHANCES THROUGH
THE AFTERNOON HOURS. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS THE
AREA DURING WED BUT A MORE SIGNIFICANT LINE SEEM LIKELY JUST AHEAD
OF A STRONG COLD FRONT CROSSING THE AREA WED AFTERNOON. FORECAST
SOUNDINGS SHOW SOME LOW LEVEL JETTING BUT IT IS ON THE WEAK SIDE. AS
IS USUALLY THE CASE IN THE CAROLINAS IN WINTER CAPE WILL BE LACKING.
RIGHT NOW THE EVENT APPEARS RATHER BENIGN AS FAR AS STRONGER STORMS
GO BUT THIS COULD CHANGE SO WILL CONTINUE TO MONITOR IT.
IMPRESSIVE PERIOD OF COLD ADVECTION BEGINS WED NIGHT BEHIND THE
EXITING FRONT AND CONTINUES INTO THU AFTERNOON BEFORE WEAKENING.
TEMPS WILL DROP NEAR TO SLIGHTLY BELOW CLIMO FOR THE REMAINDER OF
THE PERIOD. HIGH PRESSURE SHIFTS EAST ACROSS THE OH VALLEY INTO THE
MID ATLANTIC REGION...SETTING THE STAGE FOR ANOTHER WEDGE EVENT LATE
IN THE WEEK. AT THE SAME TIME THE NEXT SOUTHERN STREAM SYSTEM EJECTS
FROM THE SOUTHWEST...DEVELOPING LOW PRESSURE OVER THE NORTHERN GULF
OF MEXICO AND TIGHTENING UP THE WEDGE OVER THE EAST COAST.
ISENTROPIC LIFT DEVELOPS AS EARLY AS FRI AND STRENGTHENS SAT. GIVEN
THE PRESENCE OF DEEP MOISTURE WITH THE LIFT WILL INTRODUCE SLIGHT
CHC POP FRI AND INCREASE POP TO LOW CHC FOR SAT.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 12Z...CURRENT TRENDS ARE HOLDING...WITH NOT MUCH CHANGE TO THE
PRESENT SET OF TAFS. LOOK FOR IFR/LIFR CONDITIONS TO CONTINUE FOR
MUCH OF THE DAY. THERE WILL BE SOME EROSION IN THE CLOUDS DUE TO
SOLAR INSOLATION. THE NAM BELIEVES THERE WILL BE SOME HOLES IN THE
CEILING BY AFTERNOON...HOWEVER THE GFS KEEPS US SOCKED IN THE ENTIRE
DAY. THINK WE WILL SEE SOME BROKEN SKIES THIS AFTERNOON...STILL A
MVFR CEILING. RISING DEWPOINTS AND SOUTHERLY FLOW WILL HELP FEED THE
LOW LEVEL MOISTURE. TONIGHT...ANY MVFR CONDITIONS LEFTOVER WILL
QUICKLY DETERIORATE TO IFR...WITH PERHAPS A BRIEF SHOWER ALONG THE
COAST.
EXTENDED OUTLOOK...SHOWERS LIKELY WITH MVFR/IFR ON MONDAY. IFR CIGS
EXPECTED ON TUESDAY. CHANCE OF SHOWERS AND MVFR/IFR CONDITIONS ON
WEDNESDAY WITH A COLD FRONT. VFR ON THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SUNDAY...A DENSE FOG EVENT IS UNFOLDING AS SOUTHWEST
WINDS BRING RICH MOISTURE IN ACROSS THE VERY COLD NEARSHORE WATERS.
THE PAST FEW WEEKS OF ARCTIC CHILL HAVE TAKEN BEACH WATER
TEMPERATURES DOWN INTO THE MID TO UPPER 40S. THE DENSE FOG ADVISORY
FOR WIDESPREAD VISIBILITIES BELOW ONE MILE WILL REMAIN IN EFFECT
THROUGH MIDNIGHT TONIGHT.
OTHERWISE...A WEAK FRONT STALLED OFFSHORE SHOULD DISSIPATE LATER
TODAY AS THE REGION COMES UNDER THE INFLUENCE OF SOUTHWEST WINDS
AHEAD OF A COLD FRONT APPROACHING FROM THE NORTHWEST. WIND SPEEDS
SHOULD REMAIN 10 KT OR LESS UNTIL AFTER MIDNIGHT WHEN WIND SPEEDS
COULD KICK UP CLOSER TO 15 KT...ESPECIALLY AWAY FROM SHORE. SEAS IN
THE 2-4 FT RANGE ARE EXPECTED THROUGH TONIGHT WITH A GOOD PORTION OF
THAT DUE TO A 10-SECOND SOUTHEAST SWELL.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...SOUTHWEST FLOW AROUND 15 KT MON WILL BECOME
NORTHWEST MON EVENING AS COLD FRONT MOVES ACROSS THE WATERS. THIS
FRONT WILL HAVE SOME COLD ADVECTION WITH IT BUT STRENGTH IS LIMITED
AND INITIALLY SPEEDS WILL BE IN THE 10 TO 15 KT RANGE. GRADIENT
STARTS TO BECOME MORE DEFINED TUE MORNING AS SURFACE HIGH TO THE
NORTH BUILDS DOWN THE EAST COAST. GRADIENT BECOMES MORE DEFINED TUE
AS COASTAL TROUGH SHARPENS AND SURFACE LOW MOVES ACROSS THE LOWER MS
VALLEY. AS A RESULT NORTHEAST FLOW WILL REMAIN A SOLID 15 KT THROUGH
THE END OF THE PERIOD. SEAS WILL RUN 3 TO 5 FT THROUGH THE PERIOD
WITH THE LARGEST CONCENTRATION OF 5 FT SEAS EXPECTED TUE NIGHT.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...STRONG SOUTHWEST FLOW AHEAD OF ADVANCING COLD
FRONT WILL APPROACH 25 KT AT TIMES ON WED. COLD FRONT MOVES ACROSS
THE WATERS WED EVENING WITH STRONG OFFSHORE FLOW DEVELOPING IN ITS
WAKE. COMBINATION OF PINCHED GRADIENT AND COLD ADVECTION WILL KEEP
SPEEDS AROUND 20 KT INTO THU AFTERNOON. SLIGHT REDUCTION IN GRADIENT
AND WANING COLD ADVECTION WILL DROP NORTHEAST FLOW TO A SOLID 15 KT
FOR THE REMAINDER OF THE PERIOD. SEAS BUILD TO 4 TO 6 FT WED AHEAD
OF THE COLD FRONT. SCA SEAS LINGER INTO WED NIGHT BEFORE OFFSHORE
FLOW IS ABLE TO KNOCK SEAS BACK TO 3 TO 5 FT FOR THU AND THU NIGHT.
&&
.TIDES/COASTAL FLOODING...
AS OF 3 AM SUNDAY...WE ARE NOW TWO DAYS PAST THE NEW MOON BUT
UNUSUALLY LOW WATER LEVELS WILL CONTINUE AT LOW TIDE TODAY.
ASTRONOMICAL LOW TIDE WILL OCCUR AROUND 3:15 THIS AFTERNOON AND THE
ETSURGE/ESTOFS CONSENSUS IS FOR WATER LEVELS SOUTH OF CAPE FEAR TO
REACH -1.30 FEET MLLW...WITH LESSER DEPARTURES NORTH OF CAPE FEAR.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
AMZ250-252- 254-256.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...43
TIDES/COASTAL FLOODING...TRA
AREA FORECAST DISCUSSION
NWS PORTLAND OR
303 AM PST SUN FEB 2 2014
.SYNOPSIS...A WEAK LOW PRES SYSTEM OFF THE SOUTHERN OREGON COAST WILL
BRUSHING THE SOUTHERN PART OF THE FORECAST AREA TODAY. A COUPLE OF
WEAK UPPER LEVEL LOWS WILL BRING A CHANCE OF RAIN AND SNOW SHOWERS
TONIGHT THROUGH MONDAY NIGHT. COLDER CANADIAN AIR WILL SPREAD OVER
THE REGION TUESDAY THROUGH FRIDAY AND MAINTAIN WELL BELOW FREEZING
TEMPERATURES. A MOIST FRONT WILL BRING RAIN AND A QUICK SHOT OF SNOW
NEXT WEEKEND.
&&
.SHORT TERM...TODAY THROUGH TUESDAY...SATELLITE IMAGERY SHOWS A LOW
PRESSURE SYSTEM OFFSHORE OF THE OREGON/CALIFORNIA BORDER EARLY THIS
MORNING. HIGH CLOUDS CIRCULATING AROUND THIS LOW IS STREAMING OVER
THE PORTLAND FORECAST AREA. RADAR IMAGERY IS SHOWING VIRGA WITHIN
THESE CLOUDS. THESE CLOUDS HAVE LIMITED RADIATION COOLING SOUTH OF
MCMINNVILLE...AND INHIBITED FOG. THE SKIES WERE CLEAR OVERNIGHT NORTH
OF MCMINNVILLE AND TEMPERATURES QUICKLY DROPPED TO BELOW FREEZING.
FOG WAS ABLE TO FORM IN THE INTERIOR VALLEYS WHERE THE SKIES WERE
CLEAR...INCLUDING THE PORTLAND METRO AREA WHERE PATCHY FREEZING FOG
CAN BE EXPECTED THROUGH THE MORNING.
HIGH CLOUDS FROM THE LOW TO THE SE WILL CONTINUE OVER THE AREA
TODAY...BUT ANY RAIN SHOULD REMAIN SOUTH OF THE FORECAST
AREA...ALTHOUGH THERE IS A SLIGHT CHANCE FOR LIGHT RAIN ALONG THE
SOUTHERN BORDER TODAY.
AN UPPER LEVEL SHORTWAVE TROUGH CURRENTLY JUST NORTH OF WASHINGTON IS
SLIDING SOUTHWARD ALONG THE COAST. THIS TROUGH WILL PICK UP LOW LEVEL
MOISTURE AS IT SLIDES TOWARDS OREGON TODAY...AND POSSIBLY GENERATE
RAIN AND SNOW SHOWERS ACROSS THE PORTLAND FORECAST AREA TONIGHT. THE
BEST CHANCES CONTINUE TO BE FOR THE COAST AND OROGRAPHICALLY FAVORED
SLOPES.
A SECONDARY WEAKER SHORTWAVE CURRENTLY OVER WESTERN CANADA WILL
CONTINUE COLD AIR INTRUSION AND A THREAT FOR SHOWERS MONDAY. MOST
GUIDANCE SUGGESTS OVERNIGHT LOWS EARLY MONDAY AROUND FREEZING
...ESPECIALLY ACROSS THE NORTH. ONSHORE LOW LEVEL FLOW WITH MODEL 850
TEMPS IN THE -6 TO -8 RANGE WOULD SUGGEST SNOW LEVELS DOWN ANYWHERE
FROM JUST ABOVE THE VALLEY FLOOR TO ABOUT 1000 FEET. SHOWER ACTIVITY
WILL BE LIGHT AND SCATTERED DUE TO THE SHALLOW NATURE OF THE
MOISTURE...BUT WOULD NOT BE SURPRISED TO SEE SOME SNOW FLAKES MIXED
WITH THE RAIN. SHOWERS WILL DECREASE FROM NW TO SE MONDAY AFTERNOON
AND NIGHT.
EASTERLY WINDS WILL DEVELOP TUESDAY...CLEARING SKIES AND BEGIN TO
USHER MUCH COLDER AIR OVER THE AREA. MODELED 850MB TEMPERATURES -10
TO 12 DEG C COMBINED WITH RADIATION COOLING WILL LEAD TO LOW
TEMPERATURES IN THE 20S AND HIGH TEMPERATURES IN THE UPPER 30S.
MODELS SUGGEST THE TROUTDALE TO DALLES SURFACE PRESSURE GRADIENT WILL
STRENGTHEN TO AROUND -12 MB TUESDAY EVENING. THIS WILL RESULT IN VERY
GUSTY WINDS THROUGH THE COLUMBIA RIVER GORGE.
HARTLEY
&&
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...ECMWF AND GFS
APPEAR TO BE HONED IN ON AN UPPER AIR PATTERN THAT DRAWS AIR DOWN
FROM THE CANADIAN ARCTIC. THE MAIN THRUST OF COLD AIR IS HEADED DOWN
THE E SIDE OF THE ROCKIES...BUT BOTH GFS AND ECMWF BREAK A TROUGH OUT
TO THE W DRAWING SOME OF THE COLD AIR TO THE W. MODELS IN RECENT RUNS
HAVE PERSISTENTLY BROUGHT H8 TEMPS ON THE ORDER OF -18 W OF THE
CASCADE CREST BY THU MORNING. WITH THE LONGWAVE TROUGH OVER THE
EASTERN HALF OF CANADA IT SEEMS A LONG WAY TO BRING THE AIR
WESTWARD...BUT GIVEN THE MODEL SUPPORT IT IS DIFFICULT TO NOT GO WITH
THIS SCENARIO. THE WEAK SHORTWAVES DROPPING DOWN EARLY IN THE WEEK
ALSO HELP TO CARVE THE TROUGH WESTWARD. THIS SCENARIO WOULD BRING THE
COLDEST AIR IN SINCE EARLY DECEMBER...BUT LIKELY DRY GIVEN THE
CONTINENTAL ORIGIN.
MODELS REMAIN IN GOOD AGREEMENT GOING INTO THE WEEKEND...WHICH MAKES
FOR SOME POTENTIALLY INTERESTING WEATHER. A WARMER SYSTEM OFF THE
PACIFIC IS FORECAST TO TAP INTO SOME SUBTROPICAL MOISTURE BEFORE
MOVING INTO THE PACIFIC NW SAT. COLD AIR IN PLACE FROM LATER THIS
WEEK..AND TEMPORARILY HELD IN PLACE BY LOW LEVEL OFFSHORE FLOW COULD
MAKE FOR A MESSY TRANSITION DAY SAT AS MOISTURE OVERRUNS THE COLD
AIR BEFORE FINALLY DISPLACING IT. WITH THE MODELS IN GOOD AGREEMENT
WILL NEED TO MAKE MENTION OF WINTER PRECIPITATION POTENTIAL FOR SAT.
&&
.AVIATION...12Z TAF PACKAGE...VFR PREVAILING ACROSS THE AREA WITH
LOCAL LIFR CONDITIONS IN FOG. MID LEVEL DECK AROUND 10000 FT
ASSOCIATED WITH LOW CENTERED OFF THE SOUTH OREGON COAST SPREAD
NORTH ACROSS THE AREA DURING THE NIGHT AND HAS PREVENTED MORE
WIDESPREAD FOG FROM DEVELOPING. RADAR SHOWS A SOME LIGHT SHOWERS
SPREADING INTO THE FORECAST AREA AS FAR NORTH AS KSLE AS OF 10Z.
THE 06Z HRRR PICKS UP ON THIS SOMEWHAT AND BRINGS MORE SHOWERS
THROUGH THE AFTERNOON. THE SHOWERS WILL LIKELY FALL AS VIRGA.
COLDER CONTINENTAL TROUGH WILL DROP SOUTH ALONG THE BC COAST LATE
DAYLIGHT HOURS SUNDAY. SPOTTY SHOWERS WILL BE ADVANCING BETWEEN
03Z AND 06Z MON AS A WEAK COLD FRONT CROSSES. BETTER CHANCES OF
PRECIP WILL BE FOR THE CASCADES AND POSSIBLY BUILDING WEST TOWARD
KEUG KTTD AND MAYBE KPDX AROUND 06Z MON.
KPDX AND APPROACHES...EXPECT FOG TO DECREASE THIS MORNING AS THE
10000 FT CLOUD DECK THICKENS. VFR SHOULD PREVAIL BY 14Z WITH LOCAL
IFR ON WESTERN APPROACHES THROUGH 18Z.
&&
.MARINE...WEAK PRES GRADIENT PATTERN...WITH A WEAK LOW OVER THE
PAC NW. WINDS TO REMAIN 15 KT OR LESS INTO TUE...THEN STRONGER
OFFSHORE FLOW ARRIVES WED THAT COULD BRING 20-25 KT EASTERLY WINDS
THAT MAY LAST INTO LATE WEEK. SEAS AROUND 5 FT WILL
CONTINUE...WITH NOT MUCH CHANGE THROUGH TUE.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1000 AM CST SUN FEB 2 2014
.UPDATE...
AREAWIDE SHOWERS MOVING NORTHWARD AND LEAVING BEHIND A FEW HUNDREDTHS
TO A COUPLE OF A TENTHS OF AN INCH. 15Z SURFACE ANALYSIS HAS THE
COLD FRONT ALONG A WHARTON TO HOUSTON TO CLEVELAND LINE...SLOWLY
ADVANCING THROUGH THE CITY DURING THE HOUR AS KIAH IS 52/52...NORTH
WIND AT 14 MPH WITH LIGHT RAIN WHILE KHOU IS 70/66 WITH A SOUTH WIND
AT 7 MPH AND RAIN. THIS PRECIPITATION ACTIVITY WILL CONTINUE OVER
THE NEXT FEW HOURS...THEN WANE AND MOVE OFF TO THE EAST LATER THIS
AFTERNOON AS THE BACKING COLD AND DRY AIR MASS MOVES IN. OVERCAST
SKIES WILL REMAIN THROUGH EARLY MONDAY...GROUND HOG DAY`S MAXIMUM
TEMPERATURES HAVE ARE ALREADY BEING MET JUST DOWNSTREAM OF THE
BOUNDARY...AFTERNOON READINGS WILL REMAIN STEADY OR STEADILY FALL
THROUGH THE DAY. THE ONLY ISSUES THIS SUPER SUNDAY WILL BE LOCALLY
DENSE FOG SOUTH OF THE FRONT THIS MORNING AND A BRIEF WINDOW OF
STRONG COASTAL REGION NORTHERLIES ONCE THE FRONT ARRIVES IN THE NEXT
FEW HOURS. FRONT JUST ARRIVED IN KPSX WITH A BRISK 23 MPH NORTH
WIND. 31
&&
.PREV DISCUSSION... /ISSUED 542 AM CST SUN FEB 2 2014/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION
AVIATION...
FRONTAL BOUNDARY HAS MOVED INTO OUR NORTHERN COUNTIES AND SHOULD
BE AT OR JUST NORTH OF CXO BY 12Z. EXPECT IFR CIGS AND REDUCED
VISIBILITIES WILL CONTINUE AHEAD OF THE FRONTAL PASSAGE FOR ALL
SITES WITH SLIGHT IMPROVEMENT AS THE FRONT MOVES THROUGH. OVERALL
FORECAST REASONING REMAINS UNCHANGED FROM PREVIOUS ISSUANCE WITH
REGARDS TO RAINFALL AS LIGHT RAIN WILL CONTINUE TO INCREASE IN
COVERAGE ACROSS THE REGION THROUGH THE MORNING. PRECIPITATION
SHOULD COME TO AN END THIS AFTERNOON WITH CIGS IMPROVING TO MVFR
BY LATE EVENING AND REMAINING THERE OVERNIGHT. 38
PREV DISCUSSION... /ISSUED 448 AM CST SUN FEB 2 2014/
DISCUSSION...
AT 10Z/4AM...COLD FRONT JUST NW OF A KCXO/KDWH/KTME LINE. AHEAD
OF THE FRONT TEMPS ARE IN THE MID 60S WITH DEWPOINT TEMPS ABOUT
THAT MUCH. BEHIND THE FRONT KCLL/KUTS REPORTING TEMPS IN THE UPPER
40S. THE EXPECTATION IS FOR TEMPS TO CONTINUE TO DROP AS THE FRONT
PUSHES THROUGH SE TX AND OFF THE UPPER TX COAST. SUSPECT THAT MUCH
OF THE AREA WILL HAVE TEMPS IN THE 40S BY AFTERNOON WITH SHALLOW
COLD ADVECTION. COLD FRONT SHOULD SLOWLY REACH HOUSTON AREA AROUND
16Z OR 10AM AND THEN THE COAST AROUND 18Z OR 12PM. EXPECT AREAS OF
FOG TO STICK AROUND UNTIL FRONT PUSHES THROUGH. DENSE SEA FOG MAY
LINGER THROUGH THE MORNING ALONG THE COAST. THERE SHOULD BE ENOUGH
MOISTURE FOR SCT SHOWERS ACROSS THE AREA SO LIKE 60 POPS. LATEST
TRENDS IN HRRR SUPPORT THIS NOTION WITH GENERALLY 0.1-0.25 INCHES
OF PRECIP. MAY BE SOME ISO HALF INCH AMOUNTS OF RAIN WHERE SHOWERS
TRAIN ACROSS SOME OF THE SAME AREAS. POSSIBLE THAT ACTIVITY COULD
INCREASE IN COVERAGE LATER THIS MORNING INTO THE AFTERNOON AS
UPPER LEVEL LOW CURRENTLY APPROACHING THE BIG BEND MOVES EAST WITH
HEIGHT FALLS AND LARGE SCALE ASCENT SPREADING OVER THE AREA. 00Z
SOUNDING FROM KCRP SHOWS A STOUT CAP WITH 850MB TEMP AROUND 20C.
WILL KEEP SHOWERS IN FORECAST AND DOUBT THERE WILL BE ANY STRONG
DEEP CONVECTION DUE TO THE CAP. UPPER LEVEL TROUGH AXIS SWINGS
THROUGH 00Z-06Z MON SO EXPECT PRECIP TO END TOWARDS EVENING AND
OVERNIGHT.
UPPER LEVEL ANALYSIS HAS NEXT SYSTEM IN THE PACIFIC OFF THE
OREGON/CALIFORNIA COAST. THIS IS THE SYSTEM THAT SHOULD AFFECT TX
ON TUESDAY. SYSTEM SHOULD REACH S ROCKIES/WEST TX AROUND 12Z TUE.
IN RESPONSE MONDAY NIGHT EXPECT ISENTROPIC LIFT TO INCREASE WITH
DRIZZLE/LIGHT RAIN WITH SHOWERS BY 12Z TUE. MODELS ARE ALL IN
PRETTY GOOD AGREEMENT WITH UPPER LEVEL TROUGH MOVING INTO THE S
PLAINS WITH NEG TILT DURING THE DAY. PROBLEM IS THAT BEST PVA AND
LARGE SCALE LIFT WILL BE TO THE NORTH OF THE FORECAST AREA. MAY
STILL BE ENOUGH LIFT FOR SCT SHOWERS SO LIKE 50/60 POPS AGAIN FOR
TUESDAY WITH RAIN CHANCES DECREASING DURING THE AFTERNOON AS
TROUGH AXIS ROTATES BY THE AREA. MODELS ARE HAVING A TOUGH TIME
WITH SFC FEATURES NAMELY WEAK COASTAL LOW AND WARM FRONT
DEVELOPMENT. MODELS ARE KEEPING WARM FRONT JUST OFF THE COAST WITH
COASTAL LOW MOVING ACROSS UPPER TX COASTAL WATERS. ANY
THUNDERSTORM ACTIVITY IN THE WARM SECTOR SHOULD REMAIN IN THE GULF
BUT WILL ALSO HAVE TO CONTEND WITH CAPPING. ACTIVITY SHOULD CLEAR
OUT LATE TUE WITH NEXT STRONG COLD FRONT PUSHING THROUGH EARLY WED
MORNING. COLD ADVECTION WILL BE STRONG ON WED AND TEMPS SHOULD
STRUGGLE TO REACH THE LOW 50S.
GFS/ECMWF ARE TRYING TO COME INTO SOME CONSENSUS FOR THE END OF
WEEK FORECAST. UPPER LEVEL PATTERN REMAIN SOMEWHAT ZONAL WITH
POSSIBLE RIGHT ENTRANCE REGION TO JET AFFECTING THE AREA. MAY BE
ENOUGH WITH A WEAK DISTURBANCE MOVING THROUGH ON THURSDAY FOR SOME
WEAK ISENTROPIC LIFT. WILL KEEP 20/30 POPS FOR THUR BUT LOOKING
LIKE BEST CHANCES OF RAIN WILL COME ON FRIDAY. BOTH GFS/ECMWF
SHOWING A STRONGER SHORT WAVE MOVING INTO THE S ROCKIES AND TX ON
FRI. ECMWF LOOKS TO BE A BIT MORE PROGRESSIVE WHILE GFS A BIT
SLOWER AND AMPLIFIED. WILL KEEP SOME RAIN CHANCES GOING INTO SAT
AS TROUGH AXIS FINALLY PASSES THE AREA AND EXPECT CONDITIONS TO
DRY OUT. COLD FRONT WILL ALSO PUSH THROUGH TRAILING THE STRONGER
SHORTWAVE TROUGH. STILL GOING TO HAVE TO KEEP AN EYE ON TEMPS FOR
FRI MORNING. HAVE SOME AREAS WITH LOW TEMPS IN THE LOW 30S.
FORECAST WILL KEEP RAIN AS PRECIP TYPE BUT VERY WELL COULD BE
FREEZING RAIN/DRIZZLE BASED ON TOP-DOWN PRECIP METHODOLOGY. GIVEN
UNCERTAINTY IN OVERALL PATTERN FOR THE END OF THE WEEK WILL LEAVE
OUT MENTION OF ANY FROZEN PRECIP. STILL SOMETHING TO MONITOR GOING
FORWARD WITH FUTURE FORECASTS.
39
MARINE...
AREAS OF SEA FOG HAVE DEVELOPED ALONG THE COAST THIS MORNING AS
MOISTURE CONTINUES TO STREAM NORTHWARD AHEAD OF AN APPROACHING
COLD FRONT. THE FRONT HAS MOVED INTO SOUTHEAST TEXAS AND SHOULD
MOVE OFFSHORE AROUND MATAGORDA BAY BY MIDDAY AND OFFSHORE AT
GALVESTON BY EARLY AFTERNOON. STRONG NORTH WINDS AND BUILDING SEAS
ARE EXPECTED IN THE WAKE OF THIS FRONT AND ADVISORIES HAVE BEEN
ISSUED FOR THE COASTAL WATERS WITH CAUTION STATEMENTS FOR THE BAYS
BEGINNING MID AFTERNOON AND EXTENDING INTO LATE SUNDAY EVENING.
WINDS WILL BEGIN TO EASE OVERNIGHT BUT SEA HEIGHTS MAY NECESSITATE
EXTENDING THE ADVISORIES FURTHER. ONSHORE FLOW WILL REDEVELOP LATE
MONDAY AHEAD OF ANOTHER FRONTAL PASSAGE EXPECTED LATE TUESDAY. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 31 50 42 62 / 70 10 10 50 50
HOUSTON (IAH) 64 38 52 45 64 / 80 20 10 50 60
GALVESTON (GLS) 59 42 50 50 63 / 70 30 10 40 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES:
GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM 3 PM CST THIS AFTERNOON
THROUGH THIS EVENING FOR THE FOLLOWING ZONES: GALVESTON
BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...31
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
558 AM CST SUN FEB 2 2014
.AVIATION...
/12Z TAFS/
CONCERNS...MVFR AND IFR CIGS THROUGH THE PERIOD. WINTER
PRECIPITATION TODAY. ISOLATED CHANCES FOR THUNDER TODAY.
WIDESPREAD LIGHT RAIN IS OCCURRING ACROSS NORTH AND CENTRAL TEXAS
THIS MORNING. IN THE DFW METROPLEX...THE RAIN IS EXPECTED TO
TRANSITION TO FREEZING RAIN WITH SOME SLEET AND POSSIBLY SNOW
MIXED IN TODAY. TIMING THE CHANGEOVER FROM RAIN TO FREEZING RAIN
IS VERY CHALLENGING. THE MODELS DO NOT HAVE A GOOD HANDLE ON THE
SURFACE TEMPERATURES WHICH HAVE BEEN SLOWLY FALLING THROUGH THE
NIGHT. AREAS AROUND KAFW ARE ALREADY NEAR 32 DEGREES WITH TEMPS IN
THE LOWER TO MID 30S AS YOU MOVE WEST TO EAST ACROSS THE
METROPLEX. BASED ON THE OVERNIGHT TRENDS...THINK ALL OF THE
METROPLEX AIRPORTS WILL BE OBSERVING -FZRA BY 14Z THIS MORNING.
THE BEST CHANCES FOR SLEET OR SNOW TO MIX IN WILL BE THIS
AFTERNOON AS THE COLD AIR COLUMN DEEPENS OVER THE REGION. THE
PRECIPITATION WILL COME TO AN END LATE THIS AFTERNOON. AT
KACT...PRECIPITATION IS EXPECTED TO REMAIN ALL LIQUID RAIN AS
TEMPERATURES WILL FALL BELOW FREEZING AFTER THE RAIN HAS ENDED
THIS AFTERNOON. OVERNIGHT...TEMPERATURES WILL CONTINUE FALLING
INTO THE 20S.
STRONG NORTH WINDS BETWEEN 15-20 KTS WILL CONTINUE TODAY...
DROPPING BELOW 10 KTS LATE THIS EVENING. IN THE METROPLEX...
CEILINGS ARE CURRENTLY BETWEEN 1500-3200 FEET BUT WILL PREVAIL
BETWEEN 1000-2000 FOR MOST OF THE PERIOD. THERE IS A POTENTIAL FOR
CIGS TO FALL BELOW 1000 FEET LATE THIS MORNING AND EARLY THIS
AFTERNOON WHEN THE HEAVIEST PRECIPITATION IS EXPECTED TO OCCUR. AT
KACT...CIGS BETWEEN 1000-2000 FEET WILL PREVAIL THROUGH THE
PERIOD.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 442 AM CST SUN FEB 2 2014/
EARLY MORNING WATER VAPOR SATELLITE IMAGERY SHOWED A STRONG
SHORTWAVE TROUGH OVER THE AZ/NM/MEXICO BORDER...MOVING EAST
TOWARDS TEXAS. LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS
TROUGH WAS EVIDENT OVER FAR WEST TEXAS AND THE TX PANHANDLE WHERE
A PLUME OF DEEP WATER VAPOR WAS OBSERVED DEVELOPING OUT AHEAD OF
THE TROUGH. A 00Z UPPER AIR ANALYSIS REVEALED 500 MB TEMPERATURES
OF -18 TO -20 DEG C JUST OUT AHEAD OF THE TROUGH. THIS COLD AIR
ALOFT HAD LIKELY ADVECTED OVER LOCATIONS FROM MIDLAND TO
LUBBOCK...LOWERING STABILITY ALOFT. THIS AREA CORRESPONDED WELL
WITH OBSERVED LIGHTNING STRIKES IN CELLULAR CONVECTION OBSERVED ON
REGIONAL RADARS EXTENDING FROM MIDLAND NORTHEAST TO CHILDRESS AT
0930Z. 00Z UPPER AIR ANALYSIS SHOWED THE 850 MB FREEZING LINE
HOLDING UP IN THE TX PANHANDLE...WITH A WARM MOIST AIR MASS ALOFT
OVER NORTH TEXAS AT 10 DEG C. THIS LINE HAD OBVIOUSLY SHIFTED
SOUTH IN THE 10 HRS SINCE THE WEATHER BALLOON OBSERVATIONS AS
LIGHT SNOW WAS OBSERVED AS FAR SOUTH AS SYNDER TX AT 0930Z.
FIRST...A SUMMARY OF CHANGES TO THE PREVIOUS FORECAST:
WENT AHEAD AND EXPANDED THE WINTER WEATHER ADVISORY SOUTH TO
INCLUDE MILLS...HAMILTON...BOSQUE...HILL...ELLIS...AND KAUFMAN
COUNTIES. THIS WAS DONE PRIMARILY DUE TO AN INCREASED THREAT OF
FREEZING RAIN AND LIGHT ICE ACCUMULATIONS ON ELEVATED ROAD
SURFACES THIS AFTERNOON.
EXPECT THAT ALL WINTRY PRECIPITATION WILL REMAIN ALONG AND
NORTHWEST OF A LINE FROM GOLDTHWAITE TO HILLSBORO TO COOPER. THIS
IS AS FAR SOUTHEAST AS WE HAVE THE FREEZING LINE CREEPING THIS
AFTERNOON WHILE PRECIPITATION IS STILL ACTIVE OVER THE REGION.
TEMPERATURES WILL LIKELY FALL BELOW FREEZING ACROSS ALL OF NORTH
AND CENTRAL TEXAS TONIGHT...BUT PRECIPITATION IS EXPECTED TO END
ABRUPTLY LATE THIS AFTERNOON FROM SOUTHWEST TO NORTHEAST AS A DRY
SLOT KICKS OUT OVER THE REGION ALOFT.
BEFORE THE DRY AIR ALOFT ARRIVES HOWEVER...CONFIDENCE REMAINS HIGH
THAT WE WILL SEE ENOUGH WINTRY PRECIPITATION WHERE WE ALREADY HAD
WINTRY WEATHER ADVISORIES OR A WINTER STORM WARNING IN EFFECT.
FOR LOCATIONS THAT WERE ALREADY INCLUDED IN WINTER WEATHER
ADVISORIES OR WARNINGS...THERE WERE ONLY MINOR CHANGES MADE TO
THE PREVIOUS FORECAST. THE BIGGEST CHANGE OF NOTE WAS AN INCREASE
IN THE AMOUNTS OF FREEZING RAIN/ICE ACCUMULATION FROM A FEW
HUNDREDTHS OF AN INCH TO JUST OVER A TENTH OF AN INCH IN A NARROW
BAND JUST NORTHWEST OF THE SURFACE FREEZE LINE THIS AFTERNOON.
THIS NARROW BAND OF ENHANCED ICE ACCUMULATION EXTENDS FROM
COMANCHE TO DFW TO BONHAM. THE REASONS FOR THIS WILL BE DISCUSSED
BELOW...BUT ICE ACCUMULATIONS ARE PRIMARILY EXPECTED TO REMAIN
TIED TO ELEVATED SURFACES TODAY. MOST OF THE FREEZING RAIN IS
EXPECTED TO FALL WITH TEMPERATURES IN THE 30-32 DEGREE F
RANGE...MEANING THAT MOST OF THE RAIN WILL NOT BE COLD ENOUGH TO
FREEZE ON CONTACT WITH THE RELATIVELY WARM GROUND/SOIL
TEMPERATURES WE HAVE IN PLACE ACROSS THE REGION. THIS DOES NOT
APPLY TO BRIDGES AND OVERPASSES OF COURSE AS THESE SURFACES WILL
COOL BELOW FREEZING SOON AFTER THE AIR TEMPERATURE DROPS BELOW
FREEZING TODAY.
THE FORECAST FOR SNOWFALL AMOUNTS AND LOCATIONS REMAINS LARGELY
UNCHANGED. LOCATIONS ALONG AND NORTHWEST OF A BRECKENRIDGE TO
SHERMAN LINE STILL LOOK TO BE THE MOST FAVORABLE LOCATIONS FOR 2-4
INCHES OF SNOW ACCUMULATION WITH SOME SLEET AND FREEZING RAIN
MIXED IN. A WINTER STORM WARNING REMAINS IN EFFECT FOR THESE
LOCATIONS AS A RESULT. IN BETWEEN THE DFW AREA...WHICH IS EXPECTED
TO SEE MOSTLY FREEZING RAIN AND A LATE TRANSITION TO SLEET/SNOW...
AND THE WINTER STORM WARNING...THERE REMAINS A GREAT DEAL OF
UNCERTAINTY REGARDING THE EXACT AMOUNTS OF SNOW/SLEET/FREEZING
RAIN AS THIS REPRESENTS THE LIKELY TRANSITION ZONE BETWEEN ALL 3
PRECIPITATION TYPES THROUGHOUT THE DAY TODAY. LEFT THESE AREAS IN
AN ADVISORY FOR NOW AS CONFIDENCE IN RECEIVING AMOUNTS LARGE
ENOUGH OF ANY INDIVIDUAL TYPE OF PRECIPITATION REMAINS LOW AT THIS
TIME. SUFFICE TO SAY TRAVEL WILL STILL BE A PROBLEM FOR THESE
LOCATIONS AS A MIXED BAG OF WINTRY WEATHER WILL LEAD TO SLICK
ROADWAYS...ESPECIALLY ON BRIDGES AND OVERPASSES.
SECOND...METEOROLOGICAL DISCUSSION REGARDING OUR WINTER WEATHER
EVENT:
THE SHORTWAVE TROUGH IS EXPECTED TO SWING NORTHEAST OVER THE
REGION TODAY...SPREADING LARGE SCALE FORCING FOR ASCENT OVER THE
ENTIRE CWA THIS MORNING. AS MENTIONED AT THE BEGINNING OF THE
DISCUSSION...DIFFERENTIAL ADVECTION WILL LIKELY LEAD TO A
REDUCTION IN STABILITY ALOFT FROM WEST TO EAST THROUGHOUT THE DAY
TODAY AS WELL. THIS POINT IN PARTICULAR GREATLY COMPLICATES THE
FORECAST BECAUSE PRECIPITATION AMOUNTS BECOME MUCH MORE RESPONSIVE
TO MESOSCALE FORCING AS OPPOSED TO SYNOPTIC SCALE CONSIDERATIONS.
THIS WILL RESULT IN CELLULAR CONVECTION MIXED IN BROADER
PRECIPITATION ZONES RESULTING IN LOCALLY ENHANCED PRECIPITATION
AMOUNTS FROM WHAT IS REFLECTED IN MODEL GUIDANCE AND OUR OFFICIAL
FORECAST. IN GENERAL...WE EXPECT LOW-LEVEL TEMPERATURES TO FALL
THROUGHOUT THE DAY TODAY FROM NORTHWEST TO SOUTHEAST. WARM AIR
ADVECTION WORKING AGAINST THE SOUTHWARD MOVING CANADIAN AIRMASS IS
WHAT IS DRIVING ALL OF THE DIFFERENT PRECIPITATION TYPES ACROSS
NORTH TEXAS TODAY.
MODEL FORECAST SOUNDINGS CONSISTENTLY SHOW THAT AIR PARCELS LIFTED
FROM AROUND THE 750 MB LEVEL HAVE POSITIVE CAPE ANYWHERE FROM 100
TO 250 J/KG WITH LITTLE TO NO CONVECTIVE INHIBITION PRESENT. THIS
UPRIGHT INSTABILITY WILL RESULT IN EMBEDDED THUNDERSTORMS ACROSS
THE REGION FROM THIS MORNING THROUGH EARLY THIS AFTERNOON...SO
WENT AHEAD WITH A MENTION OF ISOLATED THUNDER IN THE FORECAST AS
CONFIDENCE IS ACTUALLY PRETTY HIGH IN THIS PANNING OUT. THE MORE
IMPORTANT QUESTION IS: HOW WILL THIS AFFECT WINTER WEATHER IMPACTS
ACROSS NORTH TEXAS TODAY? THE ANSWER TO THAT QUESTION IS
TRICKY...HOWEVER IT SEEMS MOST LIKELY THAT EMBEDDED STORMS WILL
NOT CHANGE IMPACTS MUCH FROM WHAT WERE ARE CURRENTLY HIGHLIGHTING
IN OUR WINTER STORM WARNINGS AND WINTRY WEATHER ADVISORIES.
ANY EMBEDDED THUNDERSTORMS IN THE WINTER STORM WARNING AREA WILL
ONLY SERVE TO ENHANCE SNOWFALL AMOUNTS/ACCUMULATION. THESE ARE THE
LOCATIONS WE ALREADY FEEL WILL SUFFER FROM THE WORST ROAD
CONDITIONS...SO ADDITIONAL SNOWFALL WILL ONLY EXACERBATE
DETERIORATING ROAD CONDITIONS. WHILE THIS IS NOT GOOD NEWS...A
WINTER STORM WARNING IS STILL THE MOST APPROPRIATE WAY TO ADDRESS
THESE IMPACTS AND THAT WILL NOT CHANGE WITH ADDITIONAL SNOWFALL.
IF WE GET THUNDERSTORMS ALONG A COMANCHE TO DFW TO BONHAM
LINE...WHERE WE EXPECT A TENTH OF AN INCH OF FREEZING RAIN...THIS
WILL ONLY MAKE FREEZING RAIN FALL FASTER ACROSS THE AREA. WHILE
THIS SOUNDS REALLY BAD...ITS NOT OBVIOUS THAT THIS WILL RESULT IN
ADDITIONAL ICE ACCUMULATION. HEAVIER PRECIPITATION RATES WILL
LIKELY JUST CAUSE MORE OF THE PRECIPITATION TO RUN OFF AREA
ROADWAYS...AS LONG AS TEMPERATURES REMAIN IN THE 30 O 32 DEGREE F
RANGE. NOW THIS POINT IS EXTREMELY IMPORTANT...IF TEMPERATURES
WERE TO FALL INTO THE 20S WITH ENHANCED FREEZING RAIN RATES...WE
WOULD BE IN BIG TROUBLE AS ICE WOULD ACCUMULATE VERY RAPIDLY ON
AREA ROADWAYS. HOWEVER...AT THIS TIME NEARLY ALL AVAILABLE
GUIDANCE INDICATES THAT TEMPERATURES WILL REMAIN IN THIS 30 TO 32
DEGREE RANGE OVER THE DFW AREA WHILE MEASURABLE PRECIPITATION IS
FALLING. OBVIOUSLY...WE WILL HAVE TO WATCH THIS VERY CLOSELY
THROUGHOUT THE DAY TODAY.
ONCE AGAIN FOR THOSE COUNTIES IN BETWEEN DFW AND THE WINTER STORM
WARNING...THIS IS WHERE THUNDERSTORMS COULD RESULT IN THE GREATEST
DEVIATION FROM THE CURRENT FORECAST. EMBEDDED STORMS NOT ONLY
ENHANCE PRECIPITATION AMOUNTS/RATES...BUT THEY ALSO TEND TO COOL
THE ATMOSPHERE THROUGH THE DEPTH OF THEIR UPDRAFT. THIS MAY
ACTUALLY RESULT IN A COMPLETE CHANGE OVER IN PRECIPITATION TYPE
NEAR THE PRECIPITATION TYPE RESULTING IN A QUICK CHANGE OVER FROM
FREEZING RAIN TO MODERATE TO HEAVY SLEET. WE WILL WATCH FOR ANY
PERSISTENT AREAS OF THUNDERSTORMS THAT MAY LINE UP IN THIS
TRANSITION ZONE...AND MAY HAVE TO UPGRADE SOME OF THESE AREAS TO A
WINTER STORM WARNING IF IT LOOKS LIKE A CHANGE IN PRECIPITATION
TYPE WILL RESULT IN SIGNIFICANT ADDITIONAL ACCUMULATION OF SLEET
OR SNOW.
THIS BRINGS US TO THE LEAST CERTAIN PORTION OF THE FORECAST WHICH
IS THE VERTICAL THERMAL PROFILE. 00Z AND 06Z MODELS HAVE REALLY
BEEN STRUGGLING TO KEEP UP WITH AN ACCURATE DEPICTION OF THE
FREEZING LINE AT THE SURFACE. THE 00Z NAM WAS THE ONLY MODEL THAT
HAD A GOOD HANDLE ON THE 06Z FREEZING LINE AT THE SURFACE AS EVERY
OTHER MODEL THAT WAS LOOKED AT WAS ANYWHERE FROM 2-4 DEGREES TOO
WARM. THEREFORE...THIS FORECAST FOR PRECIPITATION TYPE AND SURFACE
TEMPERATURES IS HEAVILY WEIGHTED TOWARDS THE COOLER 00Z NAM.
NOTABLY...THE 06Z RAP KEPT SURFACE TEMPERATURES ABOVE FREEZING ALL
DAY ACROSS THE DFW AREA...SO THE EXACT FORECAST FOR PRECIPITATION
TYPE REMAINS AN UNCERTAIN ONE AS OF THIS MORNING.
MODELS /EVEN THE WARMEST ONES/ CONSISTENTLY SHOW THE VERTICAL
THERMAL PROFILE WILL BE COLD ENOUGH FOR MAINLY SLEET AND SNOW
WHERE WE CURRENTLY HAVE THE WINTER STORM WARNING IN EFFECT...OR
ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE. ALSO HAVE
THE HIGHEST CONFIDENCE IN THE H850 WARM NOSE HOLDING IN PLACE
WHILE SURFACE TEMPERATURES FALL BELOW FREEZING ALONG A COMANCHE TO
DFW TO BONHAM LINE...WHICH IS WHERE WE HAVE OUR HIGHEST FREEZING
RAIN/ICE ACCUMULATIONS FORECAST. AS MENTIONED A FEW TIMES
ALREADY...IT IS IN BETWEEN THESE LOCATIONS THAT THE PRECIPITATION
TYPE IS MOST UNCERTAIN. HAVE A WINTRY MIX FORECAST FOR THESE
LOCATIONS DUE TO A VARYING DEPTH OF THE COLD AIR BASED ON YOUR
FAVORITE MODEL OF CHOICE.
IN SUMMARY:
FORECAST PRECIPITATION AMOUNTS:
2-4 INCHES OF SNOW WITH LIGHT ACCUMULATIONS OF SLEET AND FREEZING
RAIN ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE.
ONE TENTH OF A INCH OF ICE ACCUMULATION...MAINLY RESTRICTED TO
ELEVATED ROADWAYS...WITH LESS THAN A HALF INCH OF SNOW OR SLEET
ACCUMULATION EXPECTED GENERALLY ALONG A COMANCHE TO DFW TO BONHAM
LINE.
IN BETWEEN DFW AND THE WINTER STORM WARNING...1-2 INCHES OF SNOW
AND SLEET ACCUMULATION COMBINED...AND LIGHT ACCUMULATIONS OF
FREEZING RAIN/ICE POSSIBLE.
LIGHT ICE ACCUMULATIONS WILL EXTEND ALONG A GOLDTHWAITE TO
HILLSBORO TO COOPER LINE. LITTLE TO NO ACCUMULATION OF SNOW OR
SLEET IS EXPECTED FOR THESE LOCATIONS.
TO THE SOUTHEAST OF A GOLDTHWAITE TO HILLSBORO TO COOPER
LINE...PRECIPITATION IS EXPECTED TO REMAIN ALL LIQUID AT THIS
TIME...SO NO WINTRY WEATHER IMPACTS ARE EXPECTED.
NOTE: EMBEDDED THUNDERSTORMS WILL RESULT IN LOCALLY HIGHER AMOUNTS
OF PRECIPITATION IN ALL OF THESE LOCATIONS. THUNDERSTORMS ARE MOST
LIKELY FROM THIS MORNING THROUGH THE EARLY AFTERNOON HOURS.
FOR THIS EVENING AND TONIGHT...A STRONG DRY SLOT IS EXPECTED TO
BUILD OVER THE CWA FROM SOUTHWEST TO NORTHEAST RESULTING IN AN
ABRUPT END TO PRECIPITATION BY SUNSET. TEMPERATURES ARE EXPECTED
TO FALL BELOW FREEZING ACROSS THE ENTIRE CWA OVERNIGHT...SO ANY
WET ROADWAYS WILL HAVE THE POTENTIAL TO FREEZE INTO BLACK ICE.
SUB-FREEZING TEMPERATURES OVERNIGHT WILL PROLONG ANY HAZARDOUS
ROAD CONDITIONS THAT DEVELOP DURING THE DAY TODAY ACROSS NORTH
TEXAS.
REMAINDER OF THE FORECAST...MADE NO CHANGES AT THIS TIME WITH ALL
OF OUR FOCUS ON THE NEXT 24 HOURS. WIDESPREAD RAIN SHOWERS REMAIN
ON TRACK MONDAY NIGHT INTO TUESDAY MORNING WITH LITTLE CHANCES OF
FREEZING RAIN BASED ON 00Z AND 06Z MODEL DATA. ANOTHER WINTER
STORM REMAINS ON TRACK TO IMPACT THE REGION FROM THURSDAY NIGHT
INTO FRIDAY...HOWEVER LATEST MODEL GUIDANCE HAS COME DOWN ON QPF
AMOUNTS QUITE A BIT. WE WILL STILL HAVE TO WATCH THIS LATE WEEK
STORM SYSTEM CLOSELY FOR POTENTIAL IMPACTS TO THE REGION...HOWEVER
MODELS WERE AT LEAST TRENDING TOWARDS A LOWER IMPACT EVENT.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 27 42 36 54 / 90 20 10 60 30
WACO, TX 39 28 45 38 61 / 50 10 10 50 30
PARIS, TX 35 25 42 34 48 / 100 30 10 60 50
DENTON, TX 33 24 38 34 52 / 100 20 10 60 30
MCKINNEY, TX 33 25 40 34 51 / 90 20 10 60 30
DALLAS, TX 36 27 44 37 54 / 90 20 10 60 30
TERRELL, TX 35 29 44 36 54 / 90 30 10 60 40
CORSICANA, TX 39 29 48 39 57 / 70 20 10 50 40
TEMPLE, TX 39 28 48 42 63 / 40 10 10 50 30
MINERAL WELLS, TX 33 23 39 34 54 / 100 10 10 60 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR TXZ094-
095-102>106-116>121-129>134-141>145.
WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR TXZ091>093-
100-101-115.
&&
$$
82/69
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
542 AM CST SUN FEB 2 2014
.DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION
&&
.AVIATION...
FRONTAL BOUNDARY HAS MOVED INTO OUR NORTHERN COUNTIES AND SHOULD
BE AT OR JUST NORTH OF CXO BY 12Z. EXPECT IFR CIGS AND REDUCED
VISIBILITIES WILL CONTINUE AHEAD OF THE FRONTAL PASSAGE FOR ALL
SITES WITH SLIGHT IMPROVEMENT AS THE FRONT MOVES THROUGH. OVERALL
FORECAST REASONING REMAINS UNCHANGED FROM PREVIOUS ISSUANCE WITH
REGARDS TO RAINFALL AS LIGHT RAIN WILL CONTINUE TO INCREASE IN
COVERAGE ACROSS THE REGION THROUGH THE MORNING. PRECIPITATION
SHOULD COME TO AN END THIS AFTERNOON WITH CIGS IMPROVING TO MVFR
BY LATE EVENING AND REMAINING THERE OVERNIGHT. 38
&&
.PREV DISCUSSION... /ISSUED 448 AM CST SUN FEB 2 2014/
DISCUSSION...
AT 10Z/4AM...COLD FRONT JUST NW OF A KCXO/KDWH/KTME LINE. AHEAD
OF THE FRONT TEMPS ARE IN THE MID 60S WITH DEWPOINT TEMPS ABOUT
THAT MUCH. BEHIND THE FRONT KCLL/KUTS REPORTING TEMPS IN THE UPPER
40S. THE EXPECTATION IS FOR TEMPS TO CONTINUE TO DROP AS THE FRONT
PUSHES THROUGH SE TX AND OFF THE UPPER TX COAST. SUSPECT THAT MUCH
OF THE AREA WILL HAVE TEMPS IN THE 40S BY AFTERNOON WITH SHALLOW
COLD ADVECTION. COLD FRONT SHOULD SLOWLY REACH HOUSTON AREA AROUND
16Z OR 10AM AND THEN THE COAST AROUND 18Z OR 12PM. EXPECT AREAS OF
FOG TO STICK AROUND UNTIL FRONT PUSHES THROUGH. DENSE SEA FOG MAY
LINGER THROUGH THE MORNING ALONG THE COAST. THERE SHOULD BE ENOUGH
MOISTURE FOR SCT SHOWERS ACROSS THE AREA SO LIKE 60 POPS. LATEST
TRENDS IN HRRR SUPPORT THIS NOTION WITH GENERALLY 0.1-0.25 INCHES
OF PRECIP. MAY BE SOME ISO HALF INCH AMOUNTS OF RAIN WHERE SHOWERS
TRAIN ACROSS SOME OF THE SAME AREAS. POSSIBLE THAT ACTIVITY COULD
INCREASE IN COVERAGE LATER THIS MORNING INTO THE AFTERNOON AS
UPPER LEVEL LOW CURRENTLY APPROACHING THE BIG BEND MOVES EAST WITH
HEIGHT FALLS AND LARGE SCALE ASCENT SPREADING OVER THE AREA. 00Z
SOUNDING FROM KCRP SHOWS A STOUT CAP WITH 850MB TEMP AROUND 20C.
WILL KEEP SHOWERS IN FORECAST AND DOUBT THERE WILL BE ANY STRONG
DEEP CONVECTION DUE TO THE CAP. UPPER LEVEL TROUGH AXIS SWINGS
THROUGH 00Z-06Z MON SO EXPECT PRECIP TO END TOWARDS EVENING AND
OVERNIGHT.
UPPER LEVEL ANALYSIS HAS NEXT SYSTEM IN THE PACIFIC OFF THE
OREGON/CALIFORNIA COAST. THIS IS THE SYSTEM THAT SHOULD AFFECT TX
ON TUESDAY. SYSTEM SHOULD REACH S ROCKIES/WEST TX AROUND 12Z TUE.
IN RESPONSE MONDAY NIGHT EXPECT ISENTROPIC LIFT TO INCREASE WITH
DRIZZLE/LIGHT RAIN WITH SHOWERS BY 12Z TUE. MODELS ARE ALL IN
PRETTY GOOD AGREEMENT WITH UPPER LEVEL TROUGH MOVING INTO THE S
PLAINS WITH NEG TILT DURING THE DAY. PROBLEM IS THAT BEST PVA AND
LARGE SCALE LIFT WILL BE TO THE NORTH OF THE FORECAST AREA. MAY
STILL BE ENOUGH LIFT FOR SCT SHOWERS SO LIKE 50/60 POPS AGAIN FOR
TUESDAY WITH RAIN CHANCES DECREASING DURING THE AFTERNOON AS
TROUGH AXIS ROTATES BY THE AREA. MODELS ARE HAVING A TOUGH TIME
WITH SFC FEATURES NAMELY WEAK COASTAL LOW AND WARM FRONT
DEVELOPMENT. MODELS ARE KEEPING WARM FRONT JUST OFF THE COAST WITH
COASTAL LOW MOVING ACROSS UPPER TX COASTAL WATERS. ANY
THUNDERSTORM ACTIVITY IN THE WARM SECTOR SHOULD REMAIN IN THE GULF
BUT WILL ALSO HAVE TO CONTEND WITH CAPPING. ACTIVITY SHOULD CLEAR
OUT LATE TUE WITH NEXT STRONG COLD FRONT PUSHING THROUGH EARLY WED
MORNING. COLD ADVECTION WILL BE STRONG ON WED AND TEMPS SHOULD
STRUGGLE TO REACH THE LOW 50S.
GFS/ECMWF ARE TRYING TO COME INTO SOME CONSENSUS FOR THE END OF
WEEK FORECAST. UPPER LEVEL PATTERN REMAIN SOMEWHAT ZONAL WITH
POSSIBLE RIGHT ENTRANCE REGION TO JET AFFECTING THE AREA. MAY BE
ENOUGH WITH A WEAK DISTURBANCE MOVING THROUGH ON THURSDAY FOR SOME
WEAK ISENTROPIC LIFT. WILL KEEP 20/30 POPS FOR THUR BUT LOOKING
LIKE BEST CHANCES OF RAIN WILL COME ON FRIDAY. BOTH GFS/ECMWF
SHOWING A STRONGER SHORT WAVE MOVING INTO THE S ROCKIES AND TX ON
FRI. ECMWF LOOKS TO BE A BIT MORE PROGRESSIVE WHILE GFS A BIT
SLOWER AND AMPLIFIED. WILL KEEP SOME RAIN CHANCES GOING INTO SAT
AS TROUGH AXIS FINALLY PASSES THE AREA AND EXPECT CONDITIONS TO
DRY OUT. COLD FRONT WILL ALSO PUSH THROUGH TRAILING THE STRONGER
SHORTWAVE TROUGH. STILL GOING TO HAVE TO KEEP AN EYE ON TEMPS FOR
FRI MORNING. HAVE SOME AREAS WITH LOW TEMPS IN THE LOW 30S.
FORECAST WILL KEEP RAIN AS PRECIP TYPE BUT VERY WELL COULD BE
FREEZING RAIN/DRIZZLE BASED ON TOP-DOWN PRECIP METHODOLOGY. GIVEN
UNCERTAINTY IN OVERALL PATTERN FOR THE END OF THE WEEK WILL LEAVE
OUT MENTION OF ANY FROZEN PRECIP. STILL SOMETHING TO MONITOR GOING
FORWARD WITH FUTURE FORECASTS.
39
MARINE...
AREAS OF SEA FOG HAVE DEVELOPED ALONG THE COAST THIS MORNING AS
MOISTURE CONTINUES TO STREAM NORTHWARD AHEAD OF AN APPROACHING
COLD FRONT. THE FRONT HAS MOVED INTO SOUTHEAST TEXAS AND SHOULD
MOVE OFFSHORE AROUND MATAGORDA BAY BY MIDDAY AND OFFSHORE AT
GALVESTON BY EARLY AFTERNOON. STRONG NORTH WINDS AND BUILDING SEAS
ARE EXPECTED IN THE WAKE OF THIS FRONT AND ADVISORIES HAVE BEEN
ISSUED FOR THE COASTAL WATERS WITH CAUTION STATEMENTS FOR THE BAYS
BEGINNING MID AFTERNOON AND EXTENDING INTO LATE SUNDAY EVENING.
WINDS WILL BEGIN TO EASE OVERNIGHT BUT SEA HEIGHTS MAY NECESSITATE
EXTENDING THE ADVISORIES FURTHER. ONSHORE FLOW WILL REDEVELOP LATE
MONDAY AHEAD OF ANOTHER FRONTAL PASSAGE EXPECTED LATE TUESDAY. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 31 50 42 62 / 50 10 10 50 50
HOUSTON (IAH) 61 37 52 45 64 / 60 20 10 50 60
GALVESTON (GLS) 57 40 50 50 63 / 60 30 10 40 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM 3 PM CST THIS AFTERNOON
THROUGH THIS EVENING FOR THE FOLLOWING ZONES: GALVESTON
BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
448 AM CST SUN FEB 2 2014
.DISCUSSION...
AT 10Z/4AM...COLD FRONT JUST NW OF A KCXO/KDWH/KTME LINE. AHEAD
OF THE FRONT TEMPS ARE IN THE MID 60S WITH DEWPOINT TEMPS ABOUT
THAT MUCH. BEHIND THE FRONT KCLL/KUTS REPORTING TEMPS IN THE UPPER
40S. THE EXPECTATION IS FOR TEMPS TO CONTINUE TO DROP AS THE FRONT
PUSHES THROUGH SE TX AND OFF THE UPPER TX COAST. SUSPECT THAT MUCH
OF THE AREA WILL HAVE TEMPS IN THE 40S BY AFTERNOON WITH SHALLOW
COLD ADVECTION. COLD FRONT SHOULD SLOWLY REACH HOUSTON AREA AROUND
16Z OR 10AM AND THEN THE COAST AROUND 18Z OR 12PM. EXPECT AREAS OF
FOG TO STICK AROUND UNTIL FRONT PUSHES THROUGH. DENSE SEA FOG MAY
LINGER THROUGH THE MORNING ALONG THE COAST. THERE SHOULD BE ENOUGH
MOISTURE FOR SCT SHOWERS ACROSS THE AREA SO LIKE 60 POPS. LATEST
TRENDS IN HRRR SUPPORT THIS NOTION WITH GENERALLY 0.1-0.25 INCHES
OF PRECIP. MAY BE SOME ISO HALF INCH AMOUNTS OF RAIN WHERE SHOWERS
TRAIN ACROSS SOME OF THE SAME AREAS. POSSIBLE THAT ACTIVITY COULD
INCREASE IN COVERAGE LATER THIS MORNING INTO THE AFTERNOON AS
UPPER LEVEL LOW CURRENTLY APPROACHING THE BIG BEND MOVES EAST WITH
HEIGHT FALLS AND LARGE SCALE ASCENT SPREADING OVER THE AREA. 00Z
SOUNDING FROM KCRP SHOWS A STOUT CAP WITH 850MB TEMP AROUND 20C.
WILL KEEP SHOWERS IN FORECAST AND DOUBT THERE WILL BE ANY STRONG
DEEP CONVECTION DUE TO THE CAP. UPPER LEVEL TROUGH AXIS SWINGS
THROUGH 00Z-06Z MON SO EXPECT PRECIP TO END TOWARDS EVENING AND
OVERNIGHT.
UPPER LEVEL ANALYSIS HAS NEXT SYSTEM IN THE PACIFIC OFF THE
OREGON/CALIFORNIA COAST. THIS IS THE SYSTEM THAT SHOULD AFFECT TX
ON TUESDAY. SYSTEM SHOULD REACH S ROCKIES/WEST TX AROUND 12Z TUE.
IN RESPONSE MONDAY NIGHT EXPECT ISENTROPIC LIFT TO INCREASE WITH
DRIZZLE/LIGHT RAIN WITH SHOWERS BY 12Z TUE. MODELS ARE ALL IN
PRETTY GOOD AGREEMENT WITH UPPER LEVEL TROUGH MOVING INTO THE S
PLAINS WITH NEG TILT DURING THE DAY. PROBLEM IS THAT BEST PVA AND
LARGE SCALE LIFT WILL BE TO THE NORTH OF THE FORECAST AREA. MAY
STILL BE ENOUGH LIFT FOR SCT SHOWERS SO LIKE 50/60 POPS AGAIN FOR
TUESDAY WITH RAIN CHANCES DECREASING DURING THE AFTERNOON AS
TROUGH AXIS ROTATES BY THE AREA. MODELS ARE HAVING A TOUGH TIME
WITH SFC FEATURES NAMELY WEAK COASTAL LOW AND WARM FRONT
DEVELOPMENT. MODELS ARE KEEPING WARM FRONT JUST OFF THE COAST WITH
COASTAL LOW MOVING ACROSS UPPER TX COASTAL WATERS. ANY
THUNDERSTORM ACTIVITY IN THE WARM SECTOR SHOULD REMAIN IN THE GULF
BUT WILL ALSO HAVE TO CONTEND WITH CAPPING. ACTIVITY SHOULD CLEAR
OUT LATE TUE WITH NEXT STRONG COLD FRONT PUSHING THROUGH EARLY WED
MORNING. COLD ADVECTION WILL BE STRONG ON WED AND TEMPS SHOULD
STRUGGLE TO REACH THE LOW 50S.
GFS/ECMWF ARE TRYING TO COME INTO SOME CONSENSUS FOR THE END OF
WEEK FORECAST. UPPER LEVEL PATTERN REMAIN SOMEWHAT ZONAL WITH
POSSIBLE RIGHT ENTRANCE REGION TO JET AFFECTING THE AREA. MAY BE
ENOUGH WITH A WEAK DISTURBANCE MOVING THROUGH ON THURSDAY FOR SOME
WEAK ISENTROPIC LIFT. WILL KEEP 20/30 POPS FOR THUR BUT LOOKING
LIKE BEST CHANCES OF RAIN WILL COME ON FRIDAY. BOTH GFS/ECMWF
SHOWING A STRONGER SHORT WAVE MOVING INTO THE S ROCKIES AND TX ON
FRI. ECMWF LOOKS TO BE A BIT MORE PROGRESSIVE WHILE GFS A BIT
SLOWER AND AMPLIFIED. WILL KEEP SOME RAIN CHANCES GOING INTO SAT
AS TROUGH AXIS FINALLY PASSES THE AREA AND EXPECT CONDITIONS TO
DRY OUT. COLD FRONT WILL ALSO PUSH THROUGH TRAILING THE STRONGER
SHORTWAVE TROUGH. STILL GOING TO HAVE TO KEEP AN EYE ON TEMPS FOR
FRI MORNING. HAVE SOME AREAS WITH LOW TEMPS IN THE LOW 30S.
FORECAST WILL KEEP RAIN AS PRECIP TYPE BUT VERY WELL COULD BE
FREEZING RAIN/DRIZZLE BASED ON TOP-DOWN PRECIP METHODOLOGY. GIVEN
UNCERTAINTY IN OVERALL PATTERN FOR THE END OF THE WEEK WILL LEAVE
OUT MENTION OF ANY FROZEN PRECIP. STILL SOMETHING TO MONITOR GOING
FORWARD WITH FUTURE FORECASTS.
39
&&
.MARINE...
AREAS OF SEA FOG HAVE DEVELOPED ALONG THE COAST THIS MORNING AS
MOISTURE CONTINUES TO STREAM NORTHWARD AHEAD OF AN APPROACHING
COLD FRONT. THE FRONT HAS MOVED INTO SOUTHEAST TEXAS AND SHOULD
MOVE OFFSHORE AROUND MATAGORDA BAY BY MIDDAY AND OFFSHORE AT
GALVESTON BY EARLY AFTERNOON. STRONG NORTH WINDS AND BUILDING SEAS
ARE EXPECTED IN THE WAKE OF THIS FRONT AND ADVISORIES HAVE BEEN
ISSUED FOR THE COASTAL WATERS WITH CAUTION STATEMENTS FOR THE BAYS
BEGINNING MID AFTERNOON AND EXTENDING INTO LATE SUNDAY EVENING.
WINDS WILL BEGIN TO EASE OVERNIGHT BUT SEA HEIGHTS MAY NECESSITATE
EXTENDING THE ADVISORIES FURTHER. ONSHORE FLOW WILL REDEVELOP LATE
MONDAY AHEAD OF ANOTHER FRONTAL PASSAGE EXPECTED LATE TUESDAY. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 31 50 42 62 / 50 10 10 50 50
HOUSTON (IAH) 61 37 52 45 64 / 60 20 10 50 60
GALVESTON (GLS) 57 40 50 50 63 / 60 30 10 40 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM 3 PM CST THIS AFTERNOON
THROUGH THIS EVENING FOR THE FOLLOWING ZONES: GALVESTON
BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
442 AM CST SUN FEB 2 2014
.DISCUSSION...
EARLY MORNING WATER VAPOR SATELLITE IMAGERY SHOWED A STRONG
SHORTWAVE TROUGH OVER THE AZ/NM/MEXICO BORDER...MOVING EAST
TOWARDS TEXAS. LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS
TROUGH WAS EVIDENT OVER FAR WEST TEXAS AND THE TX PANHANDLE WHERE
A PLUME OF DEEP WATER VAPOR WAS OBSERVED DEVELOPING OUT AHEAD OF
THE TROUGH. A 00Z UPPER AIR ANALYSIS REVEALED 500 MB TEMPERATURES
OF -18 TO -20 DEG C JUST OUT AHEAD OF THE TROUGH. THIS COLD AIR
ALOFT HAD LIKELY ADVECTED OVER LOCATIONS FROM MIDLAND TO
LUBBOCK...LOWERING STABILITY ALOFT. THIS AREA CORRESPONDED WELL
WITH OBSERVED LIGHTNING STRIKES IN CELLULAR CONVECTION OBSERVED ON
REGIONAL RADARS EXTENDING FROM MIDLAND NORTHEAST TO CHILDRESS AT
0930Z. 00Z UPPER AIR ANALYSIS SHOWED THE 850 MB FREEZING LINE
HOLDING UP IN THE TX PANHANDLE...WITH A WARM MOIST AIR MASS ALOFT
OVER NORTH TEXAS AT 10 DEG C. THIS LINE HAD OBVIOUSLY SHIFTED
SOUTH IN THE 10 HRS SINCE THE WEATHER BALLOON OBSERVATIONS AS
LIGHT SNOW WAS OBSERVED AS FAR SOUTH AS SYNDER TX AT 0930Z.
FIRST...A SUMMARY OF CHANGES TO THE PREVIOUS FORECAST:
WENT AHEAD AND EXPANDED THE WINTER WEATHER ADVISORY SOUTH TO
INCLUDE MILLS...HAMILTON...BOSQUE...HILL...ELLIS...AND KAUFMAN
COUNTIES. THIS WAS DONE PRIMARILY DUE TO AN INCREASED THREAT OF
FREEZING RAIN AND LIGHT ICE ACCUMULATIONS ON ELEVATED ROAD
SURFACES THIS AFTERNOON.
EXPECT THAT ALL WINTRY PRECIPITATION WILL REMAIN ALONG AND
NORTHWEST OF A LINE FROM GOLDTHWAITE TO HILLSBORO TO COOPER. THIS
IS AS FAR SOUTHEAST AS WE HAVE THE FREEZING LINE CREEPING THIS
AFTERNOON WHILE PRECIPITATION IS STILL ACTIVE OVER THE REGION.
TEMPERATURES WILL LIKELY FALL BELOW FREEZING ACROSS ALL OF NORTH
AND CENTRAL TEXAS TONIGHT...BUT PRECIPITATION IS EXPECTED TO END
ABRUPTLY LATE THIS AFTERNOON FROM SOUTHWEST TO NORTHEAST AS A DRY
SLOT KICKS OUT OVER THE REGION ALOFT.
BEFORE THE DRY AIR ALOFT ARRIVES HOWEVER...CONFIDENCE REMAINS HIGH
THAT WE WILL SEE ENOUGH WINTRY PRECIPITATION WHERE WE ALREADY HAD
WINTRY WEATHER ADVISORIES OR A WINTER STORM WARNING IN EFFECT.
FOR LOCATIONS THAT WERE ALREADY INCLUDED IN WINTER WEATHER
ADVISORIES OR WARNINGS...THERE WERE ONLY MINOR CHANGES MADE TO
THE PREVIOUS FORECAST. THE BIGGEST CHANGE OF NOTE WAS AN INCREASE
IN THE AMOUNTS OF FREEZING RAIN/ICE ACCUMULATION FROM A FEW
HUNDREDTHS OF AN INCH TO JUST OVER A TENTH OF AN INCH IN A NARROW
BAND JUST NORTHWEST OF THE SURFACE FREEZE LINE THIS AFTERNOON.
THIS NARROW BAND OF ENHANCED ICE ACCUMULATION EXTENDS FROM
COMANCHE TO DFW TO BONHAM. THE REASONS FOR THIS WILL BE DISCUSSED
BELOW...BUT ICE ACCUMULATIONS ARE PRIMARILY EXPECTED TO REMAIN
TIED TO ELEVATED SURFACES TODAY. MOST OF THE FREEZING RAIN IS
EXPECTED TO FALL WITH TEMPERATURES IN THE 30-32 DEGREE F
RANGE...MEANING THAT MOST OF THE RAIN WILL NOT BE COLD ENOUGH TO
FREEZE ON CONTACT WITH THE RELATIVELY WARM GROUND/SOIL
TEMPERATURES WE HAVE IN PLACE ACROSS THE REGION. THIS DOES NOT
APPLY TO BRIDGES AND OVERPASSES OF COURSE AS THESE SURFACES WILL
COOL BELOW FREEZING SOON AFTER THE AIR TEMPERATURE DROPS BELOW
FREEZING TODAY.
THE FORECAST FOR SNOWFALL AMOUNTS AND LOCATIONS REMAINS LARGELY
UNCHANGED. LOCATIONS ALONG AND NORTHWEST OF A BRECKENRIDGE TO
SHERMAN LINE STILL LOOK TO BE THE MOST FAVORABLE LOCATIONS FOR 2-4
INCHES OF SNOW ACCUMULATION WITH SOME SLEET AND FREEZING RAIN
MIXED IN. A WINTER STORM WARNING REMAINS IN EFFECT FOR THESE
LOCATIONS AS A RESULT. IN BETWEEN THE DFW AREA...WHICH IS EXPECTED
TO SEE MOSTLY FREEZING RAIN AND A LATE TRANSITION TO SLEET/SNOW
AND THE WINTER STORM WARNING...THERE REMAINS A GREAT DEAL OF
UNCERTAINTY REGARDING THE EXACT AMOUNTS OF SNOW/SLEET/FREEZING
RAIN AS THIS REPRESENTS THE LIKELY TRANSITION ZONE BETWEEN ALL 3
PRECIPITATION TYPES THROUGHOUT THE DAY TODAY. LEFT THESE AREAS IN
AN ADVISORY FOR NOW AS CONFIDENCE IN RECEIVING AMOUNTS LARGE
ENOUGH OF ANY INDIVIDUAL TYPE OF PRECIPITATION REMAINS LOW AT THIS
TIME. SUFFICE TO SAY TRAVEL WILL STILL BE A PROBLEM FOR THESE
LOCATIONS AS A MIXED BAG OF WINTRY WEATHER WILL LEAD TO SLICK
ROADWAYS...ESPECIALLY ON BRIDGES AND OVERPASSES.
SECOND...METEOROLOGICAL DISCUSSION REGARDING OUR WINTER WEATHER
EVENT:
THE SHORTWAVE TROUGH IS EXPECTED TO SWING NORTHEAST OVER THE
REGION TODAY...SPREADING LARGE SCALE FORCING FOR ASCENT OVER THE
ENTIRE CWA THIS MORNING. AS MENTIONED AT THE BEGINNING OF THE
DISCUSSION...DIFFERENTIAL ADVECTION WILL LIKELY LEAD TO A
REDUCTION IN STABILITY ALOFT FROM WEST TO EAST THROUGHOUT THE DAY
TODAY AS WELL. THIS POINT IN PARTICULAR GREATLY COMPLICATES THE
FORECAST BECAUSE PRECIPITATION AMOUNTS BECOME MUCH MORE RESPONSIVE
TO MESOSCALE FORCING AS OPPOSED TO SYNOPTIC SCALE CONSIDERATIONS.
THIS WILL RESULT IN CELLULAR CONVECTION MIXED IN BROADER
PRECIPITATION ZONES RESULTING IN LOCALLY ENHANCED PRECIPITATION
AMOUNTS FROM WHAT IS REFLECTED IN MODEL GUIDANCE AND OUR OFFICIAL
FORECAST. IN GENERAL...WE EXPECT LOW-LEVEL TEMPERATURES TO FALL
THROUGHOUT THE DAY TODAY FROM NORTHWEST TO SOUTHEAST. WARM AIR
ADVECTION WORKING AGAINST THE SOUTHWARD MOVING CANADIAN AIRMASS IS
WHAT IS DRIVING ALL OF THE DIFFERENT PRECIPITATION TYPES ACROSS
NORTH TEXAS TODAY.
MODEL FORECAST SOUNDINGS CONSISTENTLY SHOW THAT AIR PARCELS LIFTED
FROM AROUND THE 750 MB LEVEL HAVE POSITIVE CAPE ANYWHERE FROM 100
TO 250 J/KG WITH LITTLE TO NO CONVECTIVE INHIBITION PRESENT. THIS
UPRIGHT INSTABILITY WILL RESULT IN EMBEDDED THUNDERSTORMS ACROSS
THE REGION FROM THIS MORNING THROUGH EARLY THIS AFTERNOON...SO
WENT AHEAD WITH A MENTION OF ISOLATED THUNDER IN THE FORECAST AS
CONFIDENCE IS ACTUALLY PRETTY HIGH IN THIS PANNING OUT. THE MORE
IMPORTANT QUESTION IS: HOW WILL THIS AFFECT WINTER WEATHER IMPACTS
ACROSS NORTH TEXAS TODAY? THE ANSWER TO THAT QUESTION IS
TRICKY...HOWEVER IT SEEMS MOST LIKELY THAT EMBEDDED STORMS WILL
NOT CHANGE IMPACTS MUCH FROM WHAT WERE ARE CURRENTLY HIGHLIGHTING
IN OUR WINTER STORM WARNINGS AND WINTRY WEATHER ADVISORIES.
ANY EMBEDDED THUNDERSTORMS IN THE WINTER STORM WARNING AREA WILL
ONLY SERVE TO ENHANCE SNOWFALL AMOUNTS/ACCUMULATION. THESE ARE THE
LOCATIONS WE ALREADY FEEL WILL SUFFER FROM THE WORST ROAD
CONDITIONS...SO ADDITIONAL SNOWFALL WILL ONLY EXACERBATE
DETERIORATING ROAD CONDITIONS. WHILE THIS IS NOT GOOD NEWS...A
WINTER STORM WARNING IS STILL THE MOST APPROPRIATE WAY TO ADDRESS
THESE IMPACTS AND THAT WILL NOT CHANGE WITH ADDITIONAL SNOWFALL.
IF WE GET THUNDERSTORMS ALONG A COMANCHE TO DFW TO BONHAM
LINE...WHERE WE EXPECT A TENTH OF AN INCH OF FREEZING RAIN...THIS
WILL ONLY MAKE FREEZING RAIN FALL FASTER ACROSS THE AREA. WHILE
THIS SOUNDS REALLY BAD...ITS NOT OBVIOUS THAT THIS WILL RESULT IN
ADDITIONAL ICE ACCUMULATION. HEAVIER PRECIPITATION RATES WILL
LIKELY JUST CAUSE MORE OF THE PRECIPITATION TO RUN OFF AREA
ROADWAYS...AS LONG AS TEMPERATURES REMAIN IN THE 30 O 32 DEGREE F
RANGE. NOW THIS POINT IS EXTREMELY IMPORTANT...IF TEMPERATURES
WERE TO FALL INTO THE 20S WITH ENHANCED FREEZING RAIN RATES...WE
WOULD BE IN BIG TROUBLE AS ICE WOULD ACCUMULATE VERY RAPIDLY ON
AREA ROADWAYS. HOWEVER...AT THIS TIME NEARLY ALL AVAILABLE
GUIDANCE INDICATES THAT TEMPERATURES WILL REMAIN IN THIS 30 TO 32
DEGREE RANGE OVER THE DFW AREA WHILE MEASURABLE PRECIPITATION IS
FALLING. OBVIOUSLY...WE WILL HAVE TO WATCH THIS VERY CLOSELY
THROUGHOUT THE DAY TODAY.
ONCE AGAIN FOR THOSE COUNTIES IN BETWEEN DFW AND THE WINTER STORM
WARNING...THIS IS WHERE THUNDERSTORMS COULD RESULT IN THE GREATEST
DEVIATION FROM THE CURRENT FORECAST. EMBEDDED STORMS NOT ONLY
ENHANCE PRECIPITATION AMOUNTS/RATES...BUT THEY ALSO TEND TO COOL
THE ATMOSPHERE THROUGH THE DEPTH OF THEIR UPDRAFT. THIS MAY
ACTUALLY RESULT IN A COMPLETE CHANGE OVER IN PRECIPITATION TYPE
NEAR THE PRECIPITATION TYPE RESULTING IN A QUICK CHANGE OVER FROM
FREEZING RAIN TO MODERATE TO HEAVY SLEET. WE WILL WATCH FOR ANY
PERSISTENT AREAS OF THUNDERSTORMS THAT MAY LINE UP IN THIS
TRANSITION ZONE...AND MAY HAVE TO UPGRADE SOME OF THESE AREAS TO A
WINTER STORM WARNING IF IT LOOKS LIKE A CHANGE IN PRECIPITATION
TYPE WILL RESULT IN SIGNIFICANT ADDITIONAL ACCUMULATION OF SLEET
OR SNOW.
THIS BRINGS US TO THE LEAST CERTAIN PORTION OF THE FORECAST WHICH
IS THE VERTICAL THERMAL PROFILE. 00Z AND 06Z MODELS HAVE REALLY
BEEN STRUGGLING TO KEEP UP WITH AN ACCURATE DEPICTION OF THE
FREEZING LINE AT THE SURFACE. THE 00Z NAM WAS THE ONLY MODEL THAT
HAD A GOOD HANDLE ON THE 06Z FREEZING LINE AT THE SURFACE AS EVERY
OTHER MODEL THAT WAS LOOKED AT WAS ANYWHERE FROM 2-4 DEGREES TOO
WARM. THEREFORE...THIS FORECAST FOR PRECIPITATION TYPE AND SURFACE
TEMPERATURES IS HEAVILY WEIGHTED TOWARDS THE COOLER 00Z NAM.
NOTABLY...THE 06Z RAP KEPT SURFACE TEMPERATURES ABOVE FREEZING ALL
DAY ACROSS THE DFW AREA...SO THE EXACT FORECAST FOR PRECIPITATION
TYPE REMAINS AN UNCERTAIN ONE AS OF THIS MORNING.
MODELS /EVEN THE WARMEST ONES/ CONSISTENTLY SHOW THE VERTICAL
THERMAL PROFILE WILL BE COLD ENOUGH FOR MAINLY SLEET AND SNOW
WHERE WE CURRENTLY HAVE THE WINTER STORM WARNING IN EFFECT...OR
ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE. ALSO HAVE
THE HIGHEST CONFIDENCE IN THE H850 WARM NOSE HOLDING IN PLACE
WHILE SURFACE TEMPERATURES FALL BELOW FREEZING ALONG A COMANCHE TO
DFW TO BONHAM LINE...WHICH IS WHERE WE HAVE OUR HIGHEST FREEZING
RAIN/ICE ACCUMULATIONS FORECAST. AS MENTIONED A FEW TIMES
ALREADY...IT IS IN BETWEEN THESE LOCATIONS THAT THE PRECIPITATION
TYPE IS MOST UNCERTAIN. HAVE A WINTRY MIX FORECAST FOR THESE
LOCATIONS DUE TO A VARYING DEPTH OF THE COLD AIR BASED ON YOUR
FAVORITE MODEL OF CHOICE.
IN SUMMARY:
FORECAST PRECIPITATION AMOUNTS:
2-4 INCHES OF SNOW WITH LIGHT ACCUMULATIONS OF SLEET AND FREEZING
RAIN ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE.
ONE TENTH OF A INCH OF ICE ACCUMULATION...MAINLY RESTRICTED TO
ELEVATED ROADWAYS...WITH LESS THAN A HALF INCH OF SNOW OR SLEET
ACCUMULATION EXPECTED GENERALLY ALONG A COMANCHE TO DFW TO BONHAM
LINE.
IN BETWEEN DFW AND THE WINTER STORM WARNING...1-2 INCHES OF SNOW
AND SLEET ACCUMULATION COMBINED...AND LIGHT ACCUMULATIONS OF
FREEZING RAIN/ICE POSSIBLE.
LIGHT ICE ACCUMULATIONS WILL EXTEND ALONG A GOLDTHWAITE TO
HILLSBORO TO COOPER LINE. LITTLE TO NO ACCUMULATION OF SNOW OR
SLEET IS EXPECTED FOR THESE LOCATIONS.
TO THE SOUTHEAST OF A GOLDTHWAITE TO HILLSBORO TO COOPER
LINE...PRECIPITATION IS EXPECTED TO REMAIN ALL LIQUID AT THIS
TIME...SO NO WINTRY WEATHER IMPACTS ARE EXPECTED.
NOTE: EMBEDDED THUNDERSTORMS WILL RESULT IN LOCALLY HIGHER AMOUNTS
OF PRECIPITATION IN ALL OF THESE LOCATIONS. THUNDERSTORMS ARE MOST
LIKELY FROM THIS MORNING THROUGH THE EARLY AFTERNOON HOURS.
FOR THIS EVENING AND TONIGHT...A STRONG DRY SLOT IS EXPECTED TO
BUILD OVER THE CWA FROM SOUTHWEST TO NORTHEAST RESULTING IN AN
ABRUPT END TO PRECIPITATION BY SUNSET. TEMPERATURES ARE EXPECTED
TO FALL BELOW FREEZING ACROSS THE ENTIRE CWA OVERNIGHT...SO ANY
WET ROADWAYS WILL HAVE THE POTENTIAL TO FREEZE INTO BLACK ICE.
SUB-FREEZING TEMPERATURES OVERNIGHT WILL PROLONG ANY HAZARDOUS
ROAD CONDITIONS THAT DEVELOP DURING THE DAY TODAY ACROSS NORTH
TEXAS.
REMAINDER OF THE FORECAST...MADE NO CHANGES AT THIS TIME WITH ALL
OF OUR FOCUS ON THE NEXT 24 HOURS. WIDESPREAD RAIN SHOWERS REMAIN
ON TRACK MONDAY NIGHT INTO TUESDAY MORNING WITH LITTLE CHANCES OF
FREEZING RAIN BASED ON 00Z AND 06Z MODEL DATA. ANOTHER WINTER
STORM REMAINS ON TRACK TO IMPACT THE REGION FROM THURSDAY NIGHT
INTO FRIDAY...HOWEVER LATEST MODEL GUIDANCE HAS COME DOWN ON QPF
AMOUNTS QUITE A BIT. WE WILL STILL HAVE TO WATCH THIS LATE WEEK
STORM SYSTEM CLOSELY FOR POTENTIAL IMPACTS TO THE REGION...HOWEVER
MODELS WERE AT LEAST TRENDING TOWARDS A LOWER IMPACT EVENT.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 27 42 36 54 / 90 20 10 60 30
WACO, TX 39 28 45 38 61 / 50 10 10 50 30
PARIS, TX 35 25 42 34 48 / 100 30 10 60 50
DENTON, TX 33 24 38 34 52 / 100 20 10 60 30
MCKINNEY, TX 33 25 40 34 51 / 90 20 10 60 30
DALLAS, TX 36 27 44 37 54 / 90 20 10 60 30
TERRELL, TX 35 29 44 36 54 / 90 30 10 60 40
CORSICANA, TX 39 29 48 39 57 / 70 20 10 50 40
TEMPLE, TX 39 28 48 42 63 / 40 10 10 50 30
MINERAL WELLS, TX 33 23 39 34 54 / 100 10 10 60 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR TXZ094-
095-102>106-116>121-129>134-141>145.
WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR TXZ091>093-
100-101-115.
&&
$$
/
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
659 AM EST SUN FEB 2 2014
.SYNOPSIS...
A COLD FRONT TRAILING FROM NEW YORK TO ARKANSAS WILL MOVE
SOUTHEAST ACROSS THE REGION TODAY. LOWS PRESSURE WILL TRACK ALONG
THIS FRONT AND INTO THE CAROLINAS BY TONIGHT. HIGH PRESSURE MOVES
ACROSS THE OHIO VALLEY INTO THE MID ATLANTIC ON TUESDAY...BEFORE
ANOTHER LOW AND COLD FRONT MOVE THROUGH THE AREA ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EST SUNDAY...
BROAD SOUTHWEST FLOW AT 500MB TODAY AND TONIGHT. FORECAST AREA WILL
BE UNDER RIGHT REAR QUADRANT OF UPPER JET OVERNIGHT. MORE ORGANIZED
SHORT WAVE DOES NOT GET CLOSE UNTIL AFTER MIDNIGHT. BEGINNING OF
COOLING WILL ALSO BE LATE TONIGHT. ANY CHANGE OVER FROM RAIN TO
SLEET AND SNOW IN THE FAR NORTHWEST WOULD NOT BE UNTIL AFTER
MIDNIGHT.
DEEP MOISTURE STAYS WEST OF THE BLUE RIDGE TODAY. BETTER PUSH TO THE
EAST WILL BE OVERNIGHT. TIMING IS SIMILAR TO PAST FEW MODELS RUNS
BRINGING LEADING EDGE OF RAIN INTO SOUTHEAST WEST VIRGINIA AROUND
12Z/7AM TODAY. HRRR AND LOCAL WRF ALSO BRING THE RAIN INTO SOUTHEAST
WEST VIRGINIA BETWEEN 11Z/6AM AND 14Z/9AM.
SURFACE COLD FRONT ENTERS THE FORECAST AREA FROM THE WEST THIS
MORNING AND MOVES SLOWLY SOUTHEAST...EVENTUALLY INTO NORTH CAROLINA
THIS EVENING. LOW PRESSURE MOVING ALONG THE FRONT WILL BE OVER THE
WESTERN CAROLINAS LATE TONIGHT WHICH WILL BACK THE LOW LEVEL WINDS
AND HELP ENHANCE LOW LEVEL CONVERGENCE AND LIFT.
PRECIPITABLE WATER VALUES RISE INTO THE 0.75 TO 1.0 INCH RANGE BY
00Z/7PM TONIGHT. AHEAD OF THE FRONT TODAY SURFACE DEW POINTS SURGE
WELL INTO THE MID TO UPPER 40S. GFS AND LOCAL WRF ARE SHOWING AN
AXIS OF HEAVIER QPF AMOUNTS FROM AROUND SMYTH/TAZEWELL COUNTIES INTO
ROCKBRIDGE AND AMHERST COUNTIES. COULD HAVE 0.5 TO 0.75 INCHES OF
RAIN ALONG THIS AXIS BY MONDAY MORNING.
GFS BUFKIT WAS SLIGHTLY COLDER WITH THE TEMPERATURE PROFILE BY 12Z
THAN THE NAM. APPEARS ANY MIX OR CHANGE TO SLEET WOULD BE AFTER
09Z/4AM TONIGHT AND WOULD BE CONFINED TO SOUTHEAST WEST VIRGINIA
INTO BATH COUNTY VIRGINIA.
STARTING OFF RELATIVELY MILD THIS MORNING. EVEN WITH THE INCREASING
CLOUD COVER...NOT FAR TO REACH TEMPERATURES IN THE LOWER 50S TO
LOWER 60S FOR MAXIMUM TEMPERATURES.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 430 AM EST SUNDAY...
WIDESPREAD PRECIPITATION WILL BE ONGOING MONDAY MORNING ACROSS THE
ENTIRE BLACKSBURG FORECAST AREA AS SOUTHERN STREAM SHORT WAVE AND
ASSOCIATED AREA OF LOW PRESSURE RIDES NORTHEAST ALONG FRONTAL SYSTEM
STALLED JUST TO OUR SOUTH. VERY BROAD UPWARD VERTICAL MOTION FIELD
RESULTING FROM GOOD ISENTROPIC LIFT IN LOWER 200 MILLIBARS OF THE
TROPOSPHERE COMBINED WITH IMPRESSIVE UPPER DIFFLUENT AREA FROM
COUPLED JET MAXIMA WILL GRADUALLY LIFT OFF TO THE NORTH AND EAST BY
AFTERNOON...ALLOWING FOR PRECIPITATION TO END IN MOST AREAS AS THE
AFTERNOON PROGRESSES.
SUFFICIENT COLD AIR MAY BE DRAWN INTO THE NORTHWESTERN PERIPHERY OF
THE STORM TO ALLOW FOR CHANGEOVER TO SNOW/SLEET ACROSS THE HIGHER
TERRAIN OF GREENBRIER COUNTY WV BY DAYBREAK MONDAY...AND AS FAR
SOUTH AND EAST AS THE REMAINDER OF SOUTHEAST WV...ADJACENT AREAS OF
SOUTHWEST VA...INTO THE ALLEGHANY HIGHLANDS AND SOUTHERN SHENANDOAH
VALLEY OF VA AS THE MORNING PROGRESSES. HOWEVER...ALL OF THE MODELS
CONTINUE WITH RECENT TRENDS OF NOT SUPPORTING AN AGGRESSIVE ENOUGH
PUSH OF COLDER AIR INTO THE WESTERN FLANKS OF THE STORM BEFORE THE
AREA LOSES THE MID LEVEL MOISTURE RUNNING THROUGH THE DENDRITIC
LAYER. AS A RESULT...ANY SNOWFALL ACCUMULATIONS WILL LIKELY BE
MINIMAL...PERHAPS NO MORE THAN 1-3 INCHES...AND MAINLY CONFINED TO
THE HIGHER ELEVATIONS OF WESTERN GREENBRIER COUNTY EAST INTO
PORTIONS OF THE ALLEGHANY HIGHLANDS.
WEATHER FOR LATER MONDAY AFTERNOON INTO MONDAY NIGHT WILL BE
GOVERNED BY COLD ADVECTION PATTERN WITH PLENTY OF LOW LEVEL CLOUDS
AS SURFACE RIDGE ON BACKSIDE OF STORM BUILDS EAST OF OUT THE OHIO
VALLEY...THEN SOUTHWARD ON THE EAST FLANKS OF THE APPALACHIANS
AS COOL WEDGE IS ESTABLISHED.
NEXT SOUTHERN STREAM SYSTEM EXPECTED TO BEGIN TO MAKE A MOVE
NORTHEAST TOWARD THE AREA ON TUESDAY...PASSING WEST OF THE AREA ON
TUESDAY NIGHT AS SECONDARY LOW PRESSURE DEVELOPS OVER/NEAR THE
DELMARVA AREA ON BAROCLINIC ZONE ON EAST SIDE OF COASTAL COOL WEDGE.
THIS SYSTEM WILL BRING ANOTHER PERIOD OF RAIN TO THE AREA...MOST
NOTABLY LATE TUESDAY AFTERNOON THROUGH TUESDAY NIGHT. LATER
ARRIVAL OF MAIN BODY OF PRECIPITATION SHIELD SHOULD ALLOW FOR
SURFACE TEMPERATURES TO CLIMB TO ABOVE FREEZING IN MOST AREAS ON
TUESDAY SUCH THAT ANY GLAZING SHOULD BE VERY LIMITED...AND
LOCALIZED TO THE AREAS NEAR THE BLUE RIDGE NORTH INTO THE
ALLEGHANY HIGHLANDS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 PM EST SATURDAY...
A COLD FRONT CROSSES ON WEDNESDAY WITH MORE SHOWERS AND ANOTHER
SURGE OF WARM AIR.
FORECAST THU NIGHT-SAT REMAINS COMPLICATED. HOWEVER...THE NEW 12Z
ECMWF HAS TRENDED FURTHER INLAND WITH THE TRACK OF THE LOW
PRESSURE SYSTEMS AFFECTING US FRI-SAT...WHICH TRENDS TOWARD THE
GEFS/ECWMF ENSEMBLE/CMC AND GFS. LEANED TOWARD A BLEND OF THE
ECMWF/CMC/GFS AND WPC.
FIRST...FRONT EXITS EAST GOING INTO WED EVENING WITH UPSLOPE SNOW
SHOWERS ACROSS SE WV...ALTHOUGH SFC FLOW BECOMES ANTICYCLONIC
PRETTY FAST AND THIS FAVORS A LIMITED THREAT.
LOOKING DRY HEADING INTO THURSDAY AND THURSDAY EVENING AS A STRONG
SURFACE HIGH 1041 ECWMF/1047 GFS BUILDS ESE FROM THE NRN HIGH PLAINS
INTO THE MIDWEST/WRN OHIO VALLEY BY THURSDAY EVENING. WHILE THIS
OCCURS...THE UPPER LEVEL FLOW REMAINS FAST AND SPLIT WITH SRN JET
SITUATED ACROSS SRN TX INTO THE SOUTHEAST WHILE NRN STREAM IS ACROSS
THE GREAT LAKES.
THE FORECAST PROBLEMS ARISE LATE THU NIGHT-SAT. THE ECMWF IS FASTER
IN BRINGING PCPN INTO THE SW WITH A LIGHT QPF SHOWING UP IN THE
NC MTNS BY 12Z FRIDAY. THE GFS IS 10MB STRONG THAN THE ECMWF WHICH
SLOWS THINGS DOWN. HOWEVER...WILL ALLOW FOR THE COLDER TEMPS OF
THE GFS BUT EDGE PCPN INTO THE NC MTNS AS SNOW BY FRIDAY MORNING.
DURING THE DAY FRIDAY...THE SFC HIGH STARTS TO WEDGE
SOUTHEAST...WHILE SFC FRONT AND LOW FORMS ACROSS THE GULF COAST
WITH A STRONGER SFC LOW ACROSS THE COLORADO ROCKIES. THIS WILL BE
A PERIOD WHERE WILL WATCH PIECES OF SHORTWAVE ENERGY MOVE NE ALONG
THE SOUTHEAST INTO THE MID ATLANTIC AND WHERE THE COLDER AIR STAYS
IN THE LOW LVLS WITH A WARM NOSE STARTING TO WORK IN FROM THE SW.
COULD BE A WINTRY MESS FRIDAY...WITH THE ECMWF SHOWING A
CHANGEOVER TOWARD COLD RAIN BY THE AFTERNOON...WHILE THE GFS KEEPS
THE 8H TEMPS COLD ENOUGH FOR A MORE RAIN/SNOW THREAT...WITH SOME
ICE POTENTIAL.
THE MODELS THEN DRAG THE ROCKIES LOW AND UPPER SYSTEM INTO THE SRN
PLAINS HEADING INTO SAT WHILE ANOTHER LOW FORMS ACROSS THE GULF
COAST STATES. STILL A WEDGE IS INDICATED OFF THE GFS WHILE THE
ECWMF BUMPS THE FRONTAL BOUNDARY MORE OVER WRN VA/NC KEEPING IT
RAIN. GFS SHOWING RAIN AS WELL AS THICKNESSES WARM AHEAD OF THE
UPPER TROUGH WITH STRONG SW FLOW...SO SATURDAY WILL BE WET WITH
MAYBE NRN CWA EXPERIENCING A WINTRY MIX.
SO IN A NUTSHELL...THERE IS A TREND TOWARD A WARMER/FURTHER INLAND
TRACK...BUT WE ARE NOT OUT OF THE WOODS YET FOR WINTER WX...AS
STATED FRIDAYS SYSTEM COULD BE ICY FOLLOWED BY RAIN SATURDAY. THE
CABOOSE WITH THIS SYSTEM IS INLAND AS WELL AS THE 12Z ECMWF HAS
BACKED OFF ON THE COASTAL LOW DEEPENING OFF THE NC/VA COAST SAT INTO
SUNDAY...AND HAS A TRACK INLAND OVER THE BLUE RIDGE SATURDAY
NIGHT...WHILE THE GFS IS WEST OF THE APPALACHIANS. IF THIS OCCURS
WILL BE A RAIN CHANGING TO SNOW SCENARIO BEFORE ENDING WHILE THE
NORTHEAST GETS THE HEAVY SNOW. WITH THE STRENGTH OF THE LOW AND
TROUGH...THERE COULD BE SOME WIND AND HEAVY MOUNTAIN SNOW SHOWER
ISSUES SUNDAY. STAY TUNED.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 640 AM EST SUNDAY...
MOISTURE UPSTREAM IN ADVANCE OF THE APPROACHING COLD FRONT HAS SPREAD
MVFR STRATOCUMULUS INTO SOUTHEAST WV. CEILINGS WILL CONTINUE TO
LOWER TODAY WITH 3-5KFT VALUES EXPECTED KLYH/KDAN/KROA AND KBCB
BY 20Z/3PM.
TIMING IN THE MODELS OF THE ARRIVAL OF THE RAIN HAS BEEN VERY
CONSISTENT. EXPECT RAIN TO BEGIN AROUND KLWB AND KBLF JUST AFTER
18Z/1PM...KBCB AROUND 00Z/7PM...AND KROA/KLYH/KDAN AFTER 04Z/11PM.
BY 12Z CEILINGS WILL LOWER TO IFR AT ALL TAF SITES WITH MVFR
VISIBILITIES DUE TO RAIN AND FOG.
THE COLD FRONT WILL CROSS THROUGH THE AREA TODAY AND LOW PRESSURE
WILL TRACK ALONG THE FRONT THROUGH THE CAROLINAS TONIGHT. AS
COLDER AIR MOVES IN NORTH OF THE FRONT...PRECIPITATION MAY
POSSIBLY MIX WITH OR CHANGE TO SNOW AND/OR SLEET LATE SUNDAY
NIGHT INTO MONDAY MORNING NEAR KLWB. CONFIDENCE IS LOW ON THE
ACTUAL OCCURRENCE OF SLEET OR SNOW AT KLWB.
EXTENDED AVIATION DISCUSSION...
PRECIPITATION WILL BEGIN TO EXIT THE AREA MONDAY AFTERNOON.
IMPROVEMENT IN FLIGHT CONDITIONS IS EXPECTED TO BE SLOW.
HIGH PRESSURE WEDGES SOUTH FROM NEW ENGLAND MONDAY NIGHT INTO
TUESDAY. MODELS ARE SHOWING CONSISTENT TRENDS BRINGING MORE RAIN
INTO THE AREA BY TUESDAY AFTERNOON. A STORM SYSTEM MOVING OUT OF
THE GULF COAST TUESDAY AND INTO THE MID ATLANTIC REGION WILL
PROLONG THE CHANCE OF PRECIPITATION...AS WELL AS SUB VFR CEILINGS
AND VISIBILITIES THROUGH WEDNESDAY. THEN IT DRIES OUT HEADING INTO
WED NIGHT-THU WITH VFR RETURNING.
&&
.HYDROLOGY...
AS OF 420 AM EST SUNDAY...
WIDESPREAD RAINFALL IS EXPECTED ACROSS THE AREA TODAY INTO MONDAY
MORNING. ONE HALF TO ONE INCH OF RAINFALL IS LIKELY. WITH THE
GROUND FROZEN SOLID...MUCH OF THIS RAINFALL WILL RUNOFF INTO AREA
RIVERS. AT THIS TIME MODERATE WITHIN BACK RISES ARE EXPECTED ALONG
MAINSTEM RIVERS.
A SECOND PERIOD OF RAIN IS FORECAST TUESDAY AFTERNOON THROUGH
EARLY WEDNESDAY. WE WILL CONTINUE TO MONITOR THE RAINFALL AND THE
IMPACT ON AREA RIVERS THROUGHOUT THE WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...WERT
LONG TERM...KM/WP
AVIATION...AMS/WERT
HYDROLOGY...AMS
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1141 AM PST SUN FEB 2 2014
.UPDATE...
MINOR UPDATE TO EXTEND SCATTERED POPS A BIT FURTHER NORTH AND
EAST. BROAD LIFT OCCURRING AHEAD OF UPPER LOW WITH LIGHT BAND OF
SNOW ACROSS WESTERN NV. THERE IS NO REAL FOCUS AND THE SUN CAN BE
SEEN FROM THE WFO RENO OFFICE DESPITE THE CLOUDS/LIGHT SNOW. SO
ACCUMULATIONS ARE GOING TO BE SPOTTY AND GENERALLY A DUSTING.
ALSO LOWERED TEMPS A DEGREE OR TWO AS READINGS WERE STRUGGLING TO
REACH 30 IN THE RENO AREA AT MIDDAY. HOHMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 910 AM PST SUN FEB 2 2014/
UPDATE...
UPPER LOW FORECAST TO MOVE INLAND THIS AFTERNOON AND EVENING WITH
COLD CORE/DEFORMATION TO SLIDE ACROSS SIERRA AND SOUTHERN NV.
MODEL SOUNDINGS SHOW STEEP LAPSE RATES WITH DEEP MOIST LAYER WITH
SURFACE LI/S DROPPING TO NEAR ZERO WHICH IS DECENT FOR WINTER. ALL
MODELS INCLUDING HRRR SHOW QPF ALONG SIERRA WITH SPILLOVER INTO
PARTS OF WESTERN NV MAINLY SOUTH OF HIGHWAY 50, ESPECIALLY INTO
WESTERN MINERAL COUNTY. FORECAST HAS BEEN UPDATED TO SHOW
SUBSTANTIALLY HIGHER POPS FOR EASTERN SIERRA DOWN THROUGH MONO
COUNTY THIS AFTERNOON AND EVENING. STILL LOOKS TO BE A LIGHT QPF
EVENT, BUT SEVERAL INCHES OF SNOW COULD STILL FALL. SNOW SHOWERS
WILL LIKELY IMPACT KMMH AT SOME POINT THIS AFTERNOON AND EVENING
AND WILL PUT IN SNOW SHOWERS IN THE 18Z TAF. CONFIDENCE IS LOWER
FOR KTVL-KTRK WHERE VCSH WILL BE MAINTAINED FOR NOW. HOHMANN
PREVIOUS DISCUSSION... /ISSUED 250 AM PST SUN FEB 2 2014/
SYNOPSIS...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE UPCOMING WEEK.
WEAK LOW PRESSURE AND COLD FRONT PASSAGES MAY BRING LIGHT SNOW
SHOWERS AT TIMES THROUGH MONDAY AND AGAIN ON THURSDAY, BUT LITTLE
OR NO ACCUMULATION IS EXPECTED. STRONGER LOW PRESSURE AND INCREASING
PACIFIC MOISTURE WILL BRING BETTER CHANCES FOR PRECIPITATION BY
NEXT WEEKEND.
SHORT TERM...
UPPER LOW OFF THE NORTHERN CALIFORNIA COAST IS EXPECTED TO TRACK
SOUTHEAST WITH THE CENTER STAYING OFFSHORE NEAR SAN FRANCISCO BY
LATE AFTERNOON, THEN NEAR SAN DIEGO BY EARLY MONDAY MORNING. WHILE
THE MAIN AREA OF PRECIPITATION WILL REMAIN WELL WEST OF THE SIERRA,
A SMALL DEFORMATION ZONE OVER THE SIERRA WILL LEAD TO FORMATION OF
LIGHT SNOW SHOWERS NEAR THE CREST FROM TAHOE SOUTHWARD BY MIDDAY.
LATER IN THE DAY, A FEW THUNDERSTORMS IN THE SAN JOAQUIN VALLEY
MAY SPREAD BANDS OF SNOW SHOWERS ACROSS THE SIERRA CREST MAINLY IN
MONO COUNTY BY EARLY EVENING. LOCAL ACCUMULATIONS OF AN INCH OR
TWO COULD AFFECT FAR WESTERN MONO COUNTY FROM SONORA PASS SOUTH TO
MAMMOTH MOUNTAIN, WITH A SLIM POSSIBILITY OF HIGHER AMOUNTS IF A
SNOW BAND SITS OVER THE SAME LOCATION FOR MORE THAN 2 HOURS.
ELSEWHERE OVER EASTERN CA-WESTERN NV, MID AND HIGH LEVEL CLOUDS
WILL INCREASE AND THICKEN THIS AFTERNOON BUT NO MEASURABLE SNOW IS
EXPECTED. DAYTIME TEMPS WILL STRUGGLE TO REACH 40 DEGREES IN LOWER
ELEVATIONS DUE TO POOR MIXING AND THE WIDESPREAD CLOUD COVER.
FOR MONDAY, A WEAK SHORTWAVE MOVING ACROSS THE PACIFIC NORTHWEST
TO THE NORTHERN ROCKIES WILL PUSH A BACK DOOR COLD FRONT ACROSS
THE GREAT BASIN. A FEW LIGHT SNOW SHOWERS OR FLURRIES MAY DEVELOP
MAINLY DURING THE AFTERNOON AND EVENING, BUT LATEST GUIDANCE SHOWS
WEAKER FORCING ALONG THE FRONT AND SHALLOW MOISTURE WHICH WILL
LIMIT THE POTENTIAL FOR ACCUMULATING SNOWFALL IN WESTERN NEVADA.
THE MAIN EFFECT OF THIS FRONT WILL BE A REINFORCING SHOT OF COLDER
AIR, AND A SHORT PERIOD OF BRISK NORTHWEST WINDS AROUND 10-15 MPH
IN THE LATE AFTERNOON AND EVENING.
FOR TUESDAY, DRY NORTHWEST FLOW ALOFT WILL CONTINUE WITH AREAS OF
CIRRUS SPREADING OVER THE REGION. A CHILLY START TO THE DAY WITH
LIMITED MIXING WILL LEAD TO ANOTHER DAY WITH TEMPERATURES 5-10
DEGREES BELOW NORMAL. MJD
LONG TERM...WEDNESDAY THROUGH SUNDAY...
LOW PRESSURE REMAINS OVER THE MOUNTAIN WEST THROUGH THE SECOND HALF
OF THE WEEK WITH BREEZY NORTHWEST FLOW AND BELOW NORMAL TEMPERATURES.
ANOTHER SHORTWAVE DROPS IN FROM THE NORTH ON THURSDAY.
THIS WILL ALSO PUSH A COLD FRONT THROUGH NORTHERN CA AND THE GREAT
BASIN, WITH GOOD LOW-LEVEL FRONTOGENESIS AND DYNAMICS ALOFT. THIS
WILL BRING A CHANCE OF CONVECTIVE SNOW SHOWERS TO THE SIERRA AND
WESTERN NEVADA, ALTHOUGH THE LATEST MODEL RUNS SEEM TO BE TRENDING
FURTHER INTO NORTHEASTERN NEVADA WITH THE MAJORITY OF THE PRECIP
THURSDAY NIGHT. THIS SHORTWAVE WILL ALSO BRING SOME EXTREMELY
COLD AIR ALOFT, AROUND -15C TO -20C AT 700 MB, MEANING THAT SNOW
LEVEL WOULD BE DOWN TO ALL VALLEY FLOORS. TEMPERATURES WILL GO
FROM COLD TO EVEN COLDER ON FRIDAY BEHIND THE FRONT WITH HIGH
TEMPERATURES IN THE 20S AND LOW 30S. AT THIS TIME, FORECASTER
CONFIDENCE IS LOW WITH REGARD TO THE SNOW SHOWERS ON THURSDAY, BUT
CONFIDENCE ON THE COLD AIR IS AT MEDIUM TO HIGH.
SHORTWAVE RIDGE WILL BUILD IN SATURDAY AHEAD OF THE NEXT WAVE OF
PRECIP MOVING TOWARDS THE WEST COAST. A LOW PRESSURE ANOMALY WILL
DEVELOP OVER THE GULF OF ALASKA FOR NEXT WEEKEND AS HIGH PRESSURE
OVER THE EASTERN PACIFIC GETS PINCHED OFF OVER THE BERING SEA. THIS
HAS THE CHANCE OF BRINGING ADDITIONAL MOISTURE INTO THE PAC NW AND
NORTHERN CA NEXT WEEKEND AND INTO THE SECOND WEEK OF FEBRUARY. THAT
BEING SAID, THERE IS ALSO A POSSIBILITY THAT THE BULK OF THE MOISTURE
COULD RIDE UP INTO THE PAC NW AND MISS THE SIERRA. THESE DETAILS
WILL BE WORKED OUT IN THE COMING DAYS AS WE GET A BETTER PICTURE.
HOON
AVIATION...
MVFR VIS FROM FZFG EXPECTED AT KTRK THIS MORNING ALTHOUGH HIGH
CLOUDS MOVING IN MAY LIMIT THE DEVELOPMENT. OTHERWISE VFR CONDITIONS
AND LIGHT WINDS FOR TODAY.
LOW PRESSURE MOVES DOWN THE CALIFORNIA COAST TONIGHT BRINGING SNOW
SHOWERS TO THE SIERRA AND POTENTIALLY IMPACTING AIR OPERATIONS AT
KTRK, KTVL, AND KMMH. EVEN THOUGH LIGHT SNOW IS EXPECTED MAINLY
ALONG THE SIERRA CREST, THERE IS AROUND A 30% CHANCE OF SNOW
ACCUMULATIONS UP TO AN INCH TONIGHT AT KMMH. FARTHER NORTH AT KTRK
AND KTVL THERE IS LESS THAN 10% CHANCE OF ACCUMULATIONS. HOON
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
910 AM PST SUN FEB 2 2014
.UPDATE...
UPPER LOW FORECAST TO MOVE INLAND THIS AFTERNOON AND EVENING WITH
COLD CORE/DEFORMATION TO SLIDE ACROSS SIERRA AND SOUTHERN NV.
MODEL SOUNDINGS SHOW STEEP LAPSE RATES WITH DEEP MOIST LAYER WITH
SURFACE LI/S DROPPING TO NEAR ZERO WHICH IS DECENT FOR WINTER. ALL
MODELS INCLUDING HRRR SHOW QPF ALONG SIERRA WITH SPILLOVER INTO
PARTS OF WESTERN NV MAINLY SOUTH OF HIGHWAY 50, ESPECIALLY INTO
WESTERN MINERAL COUNTY. FORECAST HAS BEEN UPDATED TO SHOW
SUBSTANTIALLY HIGHER POPS FOR EASTERN SIERRA DOWN THROUGH MONO
COUNTY THIS AFTERNOON AND EVENING. STILL LOOKS TO BE A LIGHT QPF
EVENT, BUT SEVERAL INCHES OF SNOW COULD STILL FALL. SNOW SHOWERS
WILL LIKELY IMPACT KMMH AT SOME POINT THIS AFTERNOON AND EVENING
AND WILL PUT IN SNOW SHOWERS IN THE 18Z TAF. CONFIDENCE IS LOWER
FOR KTVL-KTRK WHERE VCSH WILL BE MAINTAINED FOR NOW. HOHMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 250 AM PST SUN FEB 2 2014/
SYNOPSIS...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE UPCOMING WEEK.
WEAK LOW PRESSURE AND COLD FRONT PASSAGES MAY BRING LIGHT SNOW
SHOWERS AT TIMES THROUGH MONDAY AND AGAIN ON THURSDAY, BUT LITTLE
OR NO ACCUMULATION IS EXPECTED. STRONGER LOW PRESSURE AND INCREASING
PACIFIC MOISTURE WILL BRING BETTER CHANCES FOR PRECIPITATION BY
NEXT WEEKEND.
SHORT TERM...
UPPER LOW OFF THE NORTHERN CALIFORNIA COAST IS EXPECTED TO TRACK
SOUTHEAST WITH THE CENTER STAYING OFFSHORE NEAR SAN FRANCISCO BY
LATE AFTERNOON, THEN NEAR SAN DIEGO BY EARLY MONDAY MORNING. WHILE
THE MAIN AREA OF PRECIPITATION WILL REMAIN WELL WEST OF THE SIERRA,
A SMALL DEFORMATION ZONE OVER THE SIERRA WILL LEAD TO FORMATION OF
LIGHT SNOW SHOWERS NEAR THE CREST FROM TAHOE SOUTHWARD BY MIDDAY.
LATER IN THE DAY, A FEW THUNDERSTORMS IN THE SAN JOAQUIN VALLEY
MAY SPREAD BANDS OF SNOW SHOWERS ACROSS THE SIERRA CREST MAINLY IN
MONO COUNTY BY EARLY EVENING. LOCAL ACCUMULATIONS OF AN INCH OR
TWO COULD AFFECT FAR WESTERN MONO COUNTY FROM SONORA PASS SOUTH TO
MAMMOTH MOUNTAIN, WITH A SLIM POSSIBILITY OF HIGHER AMOUNTS IF A
SNOW BAND SITS OVER THE SAME LOCATION FOR MORE THAN 2 HOURS.
ELSEWHERE OVER EASTERN CA-WESTERN NV, MID AND HIGH LEVEL CLOUDS
WILL INCREASE AND THICKEN THIS AFTERNOON BUT NO MEASURABLE SNOW IS
EXPECTED. DAYTIME TEMPS WILL STRUGGLE TO REACH 40 DEGREES IN LOWER
ELEVATIONS DUE TO POOR MIXING AND THE WIDESPREAD CLOUD COVER.
FOR MONDAY, A WEAK SHORTWAVE MOVING ACROSS THE PACIFIC NORTHWEST
TO THE NORTHERN ROCKIES WILL PUSH A BACK DOOR COLD FRONT ACROSS
THE GREAT BASIN. A FEW LIGHT SNOW SHOWERS OR FLURRIES MAY DEVELOP
MAINLY DURING THE AFTERNOON AND EVENING, BUT LATEST GUIDANCE SHOWS
WEAKER FORCING ALONG THE FRONT AND SHALLOW MOISTURE WHICH WILL
LIMIT THE POTENTIAL FOR ACCUMULATING SNOWFALL IN WESTERN NEVADA.
THE MAIN EFFECT OF THIS FRONT WILL BE A REINFORCING SHOT OF COLDER
AIR, AND A SHORT PERIOD OF BRISK NORTHWEST WINDS AROUND 10-15 MPH
IN THE LATE AFTERNOON AND EVENING.
FOR TUESDAY, DRY NORTHWEST FLOW ALOFT WILL CONTINUE WITH AREAS OF
CIRRUS SPREADING OVER THE REGION. A CHILLY START TO THE DAY WITH
LIMITED MIXING WILL LEAD TO ANOTHER DAY WITH TEMPERATURES 5-10
DEGREES BELOW NORMAL. MJD
LONG TERM...WEDNESDAY THROUGH SUNDAY...
LOW PRESSURE REMAINS OVER THE MOUNTAIN WEST THROUGH THE SECOND HALF
OF THE WEEK WITH BREEZY NORTHWEST FLOW AND BELOW NORMAL TEMPERATURES.
ANOTHER SHORTWAVE DROPS IN FROM THE NORTH ON THURSDAY.
THIS WILL ALSO PUSH A COLD FRONT THROUGH NORTHERN CA AND THE GREAT
BASIN, WITH GOOD LOW-LEVEL FRONTOGENESIS AND DYNAMICS ALOFT. THIS
WILL BRING A CHANCE OF CONVECTIVE SNOW SHOWERS TO THE SIERRA AND
WESTERN NEVADA, ALTHOUGH THE LATEST MODEL RUNS SEEM TO BE TRENDING
FURTHER INTO NORTHEASTERN NEVADA WITH THE MAJORITY OF THE PRECIP
THURSDAY NIGHT. THIS SHORTWAVE WILL ALSO BRING SOME EXTREMELY
COLD AIR ALOFT, AROUND -15C TO -20C AT 700 MB, MEANING THAT SNOW
LEVEL WOULD BE DOWN TO ALL VALLEY FLOORS. TEMPERATURES WILL GO
FROM COLD TO EVEN COLDER ON FRIDAY BEHIND THE FRONT WITH HIGH
TEMPERATURES IN THE 20S AND LOW 30S. AT THIS TIME, FORECASTER
CONFIDENCE IS LOW WITH REGARD TO THE SNOW SHOWERS ON THURSDAY, BUT
CONFIDENCE ON THE COLD AIR IS AT MEDIUM TO HIGH.
SHORTWAVE RIDGE WILL BUILD IN SATURDAY AHEAD OF THE NEXT WAVE OF
PRECIP MOVING TOWARDS THE WEST COAST. A LOW PRESSURE ANOMALY WILL
DEVELOP OVER THE GULF OF ALASKA FOR NEXT WEEKEND AS HIGH PRESSURE
OVER THE EASTERN PACIFIC GETS PINCHED OFF OVER THE BERING SEA. THIS
HAS THE CHANCE OF BRINGING ADDITIONAL MOISTURE INTO THE PAC NW AND
NORTHERN CA NEXT WEEKEND AND INTO THE SECOND WEEK OF FEBRUARY. THAT
BEING SAID, THERE IS ALSO A POSSIBILITY THAT THE BULK OF THE MOISTURE
COULD RIDE UP INTO THE PAC NW AND MISS THE SIERRA. THESE DETAILS
WILL BE WORKED OUT IN THE COMING DAYS AS WE GET A BETTER PICTURE.
HOON
AVIATION...
MVFR VIS FROM FZFG EXPECTED AT KTRK THIS MORNING ALTHOUGH HIGH
CLOUDS MOVING IN MAY LIMIT THE DEVELOPMENT. OTHERWISE VFR CONDITIONS
AND LIGHT WINDS FOR TODAY.
LOW PRESSURE MOVES DOWN THE CALIFORNIA COAST TONIGHT BRINGING SNOW
SHOWERS TO THE SIERRA AND POTENTIALLY IMPACTING AIR OPERATIONS AT
KTRK, KTVL, AND KMMH. EVEN THOUGH LIGHT SNOW IS EXPECTED MAINLY
ALONG THE SIERRA CREST, THERE IS AROUND A 30% CHANCE OF SNOW
ACCUMULATIONS UP TO AN INCH TONIGHT AT KMMH. FARTHER NORTH AT KTRK
AND KTVL THERE IS LESS THAN 10% CHANCE OF ACCUMULATIONS. HOON
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
308 PM MST SUN FEB 2 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 308 PM MST SUN FEB 2 2014
TWO WEATHER SYSTEMS BLEND TOGETHER TO FORM THE NEXT WINTER STORM
TO IMPACT THE REGION. IN THE NEAR TERM...THE CIRCULATION OVER
CENTRAL CALIFORNIA IS PROGGED TO DROP SOUTHEAST INTO ARIZONA ON
MONDAY. A DEFORMATION ZONE DEVELOPS OVER WEST CENTRAL COLORADO
WHERE THE NRN AND SRN STREAM MEGRE. HIGH CLOUDS SPREAD FROM THE
SOUTHWEST THIS EVENING WITH THE MID LEVEL MOISTURE ARRIVING LATE
TONIGHT. THE RAP MODEL SHOWS THE THREAT OF SNOW IN THE WESTERN
SLOPE MOUNTAIN BEGINNING AFTER MIDNIGHT...BUT DYNAMICAL ASCENT
DOES NOT REACH SOUTHWEST COLORADO UNTIL MONDAY MORNING. SNOW
EXPANDS AND ENCOMPASSES THE MOUNTAIN AREAS BY NOONTIME MONDAY.
STATIC STABILITY IS LOW WITH MODEL DATA DEPICTING SOME CAPE
VALUES. THIS SUGGESTS THAT DEVELOPING SNOW CLOUDS WILL HAVE SOME
UPDRAFTS THAT SHOULD ENHANCE THE OROGRAPHIC AND DYNAMICAL
COMPONENTS. SURFACE PROGS SHOWS A BROAD AREA OF LOW PRESSURE
CENTERED OVER SOUTHWEST COLORADO. GIVEN THESE FACTORS...BELIEVE
THAT HOISTING THE WINTER STORM WATCH IS THE PRUDENT THING TO DO.
HIGH COUNTRY QPF VALUES SUPPORT AREAS OF WARNING CRITERIA BEING
REACHED BY TUESDAY AFTERNOON. EXPECT SOME SNOW TO EXPAND INTO THE
LOWER VALLEYS AND LATER SHIFTS MAY NEED TO CONSIDER ADDING WINTER
WEATHER ADVISORIES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 308 PM MST SUN FEB 2 2014
AN AMPLIFIED EASTERN PACIFIC/ALASKAN RIDGE IN THE WEST AND A STRONG
BERMUDA HIGH OVER THE CARIBBEAN WILL KEEP A BROAD...ACTIVE TROF
ACROSS MUCH OF THE CONUS THIS WEEK. THE PACIFIC JET IN THE BASE OF
THIS TROF WILL DIVE FROM THE PACIFIC NORTHWEST INTO THE DESERT
SOUTHWEST BEFORE ARCING BACK INTO THE UPPER MIDWEST THROUGH MUCH OF
THIS PERIOD. MORE ORGANIZED PIECES OF ENERGY MOVING THROUGH THE FLOW
WILL FORCE THE JET TO BECOME MORE CYCLONICALLY CURVED NEAR THE 4
CORNERS AT EACH END OF THE NEW WORK WEEK...WHICH WILL ADD SOME
ADDITIONAL ASCENT OVER OUR REGION. WITH THE JET TO OUR
SOUTH...COLD TEMPERATURES WILL BE IN PLACE. THIS COULD LEAVE HIGH
TEMPERATURES SOME 20 DEGREES BELOW NORMAL ACROSS PORTIONS OF THE
CWA. PIECES OF UNORGANIZED AND ORGANIZED ENERGY AND PACIFIC
MOISTURE PUSHED ALONG WITH THE JET WILL ALSO BRING PERIODS OF
SNOW...HEAVY AT TIMES...TO OUR CWA MOUNTAINS WITH VALLEYS LIKELY
TO SEE SOME WHITE STUFF AS WELL.
TUESDAY MORNING THE FIRST OF THE MORE ORGANIZED SYSTEMS WILL BE OVER
THE CWA. THE PACIFIC WAVE WILL HAVE MOVED INTO THE SOUTHERN PLAINS
BY SUNRISE...BUT THE UPSTREAM ARCTIC WAVE WILL BE SWINGING ACROSS
THE WYOMING AND NORTHERN COLORADO ROCKIES THROUGH THE DAY. 290K
MOISTURE TRANSPORT VECTORS SHOW THIS WAVE BRINGING IN ADDITIONAL
MOISTURE AND PWAT TOPS OUT AT NEAR .25 INCH. THIS IS HALF OF LAST
WEEK BUT WITH STRONGER INSTABILITY IN PLACE...IT SHOULD BE ABLE TO
CONTINUE THE THREAT OF MODERATE TO HEAVY MOUNTAIN SNOW SHOWERS
THROUGH THE DAY. CROSS SECTIONS SHOW NEG EPV NEAR MOUNTAIN LEVEL
WITH WESTERLY OROGRAPHICS HELPING TO RELEASE THIS INSTABILITY.
MODELS ALSO SUGGEST THIS WAVE WILL BE GIVING THE TRUE ARCTIC FRONT
A SHOVE SOUTHWARD INTO NORTHWEST COLORADO THROUGH THE AFTERNOON.
TEMPERATURES COULD VERY WELL BE DROPPING THROUGH THE MID TEENS
NORTH OF HIGHWAY 40 AFTER MID DAY. THIS FRONT WOULD ALSO SERVE AS
ADDITIONAL LOW LEVEL FOCUS FOR SNOW IN THE NORTHERN VALLEYS WHERE
DENDRITIC TEMPERATURES WILL BECOME MORE FAVORABLE FOR LOW DENSITY
SNOW PRODUCTION.
A SHORT LULL CAN BE EXPECTED LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING IN THE WAKE OF THIS WAVE. THETA SURFACES REVEAL PACIFIC
MOISTURE ENTRAINING IN THE FLOW OVER THE GREAT BASIN. FAVORABLE
OROGRAPHICS THROUGH A SATURATED DENDRITIC LAYER OVER THE HIGH
COUNTRY LOOKS TO KEEP LIGHT SNOW PROCESSES GOING...WITH AFTERNOON
INSTABILITY BOOSTING RATES AT TIMES. IT COULD BE A PROLONGED PERIOD
OF LIGHT SNOW FOR MANY AREAS BUT AT THIS TIME UNSURE OF IMPACTS
SUITED FOR WINTER HEADLINES. LARGE SCALE ASCENT...MOISTURE AND
INSTABILITY ALL GET A STRONG BOOST BY FRIDAY AS AGAIN WEST COAST
ENERGY MERGES OVER THE ROCKIES. THIS STORM HAS THE POTENTIAL TO
BRING ANOTHER ROUND OF SIGNIFICANT SNOW THE REGION THROUGH GOING
INTO THE WEEKEND. THIS STORM IS MUCH COLDER AND NOT AS MOIST BUT
TEMPERATURES SUGGEST THE LOWER DENSITY SNOW WILL BE EASIER TO PILE
UP. THERE IS ALSO A DEEPER FOCUS FOR ASCENT WITH A COLD FRONT
PUSHING THROUGH THE CWA FRIDAY EVENING...STAY TUNED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 308 PM MST SUN FEB 2 2014
VFR CONDITIONS WILL PREVAIL UNTIL ABOUT 09Z...THEN CIGS WILL BEGIN
TO LOWER ACROSS SOUTHWEST AND WEST CENTRAL COLORADO WITH
INCREASING -SN FORMING OVER THE PEAKS. MOUNTAIN TOPS BECOME
OBSCURED BY 14Z WITH VIS 5SM -SN AT KTEX. CONDITIONS WILL SLOWLY
DETERIORATE AT SKI COUNTRY TAF SITES WITH IFR CIGS/VIS POSSIBLE FROM
PASSING BANDS OF SNOW...ESPECIALLY AFTER 18Z. THERE IS A 30
PERCENT CHANCE THAT SNOW WILL IMPACT LOWER ELEVATED TAF SITES SUCH
AS KGJT...KMTJ AND KRIL AS WELL.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM 3 AM MST MONDAY THROUGH MONDAY
EVENING COZ009-013-018-019.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY EVENING
ABOVE 7500 FEET FOR THE COZ017.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY EVENING
COZ010-012.
UT...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY EVENING
ABOVE 7500 FEET FOR THE UTZ028.
&&
$$
SHORT TERM...PF
LONG TERM...15
AVIATION...PF
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
555 PM EST SUN FEB 2 2014
.SYNOPSIS...
THE ACTIVE WEATHER PATTERN CONTINUES THIS WEEK. A LOW PRESSURE
SYSTEM WILL LIFT NE OFF THE MID ATLANTIC COAST JUST SOUTH OF OUR
REGION TOMORROW...BRINGING OUR FIRST ROUND OF WINTRY PRECIPITATION
THIS WEEK. HIGH PRESSURE WILL FOLLOW MONDAY NIGHT AND TUESDAY BEFORE
ANOTHER LOW PRESSURE SYSTEM FROM THE TENNESSEE RIVER VALLEY BRINGS A
WINTRY MIX TO THE REGION TUESDAY NIGHT AND WEDNESDAY. MORE HIGH
PRESSURE IS EXPECTED THURSDAY AND FRIDAY BEFORE ONE MORE LOW MOVES
INTO THE REGION ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
WINTER STORM WARNING IN AFFECT FOR THE PHILADELPHIA METRO AREA WITH
WINTER WEATHER ADVISORIES IN PLACE FURTHER NORTH AND WEST OF THIS
THROUGH TOMORROW EVENING. MORE IN THE SHORT TERM SECTION BELOW.
555 PM NOTE: WE ARE REVIEWING GUIDANCE FOR A POTENTIAL SLIGHT
UPGRADE IN AMOUNTS AND SLIGHT EXPANSION NORTHWESTWARD IN THE
WARNING CONFIGURATION AND POSSIBLY ADDING A LAYER OF ADVY ALONG
THE SOUTH BORDER OF THE WARNING. WE`LL HAVE WHATEVER CHANGES WE
ARE CONFIDENT OF...COMPLETED BY 8 PM. THE ONE ZONE WE ARE VERY
CONFIDENT OF UPGRADING TO A WARNING IS WESTERN CHESTER COUNTY TO
BRIDGE WITH THE STATE COLLEGE LATEST UPDATE FOR LANCASTER COUNTY.
THE PSEUDO-ARCTIC FRONT TO OUR WEST-NORTHWEST WILL CONTINUE TO
SLOWLY SLIDE THROUGH THE REGION TODAY PROVIDING SOME CHANCES FOR
SHOWERS, MOSTLY LIQUID AS THERMAL PROFILES CONTINUE TO SHOW LOW-
LEVEL WARMING TAKING PLACE. THE MAJORITY OF THE ENERGY ASSOCIATED
WITH THE FRONT CONTINUES TO REMAIN ACROSS OUR NORTHWESTERN ZONES
AND THIS IS WHERE WE WILL CONTINUE WITH THE HIGHER CHANCES FOR
RAIN TONIGHT THEN TRANSITIONING TO A MIX LATER THIS EVENING AS
SOME COLD AIR STARTS TO SEEP INTO THE REGION.
THERE IS INCREASING CONCERN THAT ANY PRECIPITATION BEGINNING AS RAIN
NORTH AND WEST OF PHILADELPHIA BETWEEN 2 AM AND 5 AM WILL QUICKLY
CHANGE TO SNOW WITH POSSIBLY A BRIEF VERY PERIOD OF SLEET IN THE
TRANSITION. LATEST 18Z/2 GFS AND NAM THERMAL PROFILES HAVE THE
ENTIRE VERTICAL THERMAL STRUCTURE BELOW FREEZING BY 10Z! THE
QUESTION ARE THE MODELS TOO COLD TOO FAST? EVEN THE ECMWF HAS AN
ENTIRELY FREEZING COLUMN AT 11Z!
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
**HIGH IMPACT HEAVY SNOW EXPECTED FOR 2 TO 5 HOURS MONDAY MORNING
IN THE WARNING AREA**
18Z NAM/GFS MODEL GUIDANCE IS NOW IN AGREEMENT ON AN AXIS OF LARGE
DENDRITE GROWTH AT 12Z FROM SOUTHEAST PA THROUGH NORTHERN MARYLAND.
IT WILL BE DIFFICULT TO BELIEVE WE DONT SEE A COUPLE OF HOURS OF
1/4S+ IN THE WARNING AREA NEAR OR JUST AFTER DAYBREAK. WHILE THIS
IS MODELED GUIDANCE...WE THINK IT PROBABLE SINCE THE TWO NCEP
PRIMARY MODELS WE USE ARE IN AGREEMENT. THIS AXIS OF HEAVY SNOW
SLIPS EWD PASSING OFF THE COAST BY 1PM.
SNOW WATER EQUIVALENTS MAY ONLY BE 10 TO 1 AND SO WE WONT INFLATE
AMOUNTS... BUT SW RATIO MAY MAKE THIS MORE DIFFICULT TO REMOVE
AFTER THE STORM.
WE CHECKED THE NAM 21Z TEMPS AND THEY ARE BASICALLY WITHIN 2F OF
THE 18Z PREDICTION ALONG AND N OF I80.
LATEST 21Z/2 RAP HAS 3 NEW INCHES OF SNOW BETWEEN 9Z AND 15Z IN THE
POCONOS AND 2 INCHES THROUGHOUT NNJ THOUGH ONLY 1 INCH NEAR I95 IN
PHILADELPHIA. IF THE STRONG FGEN DOES NOT MATERIALIZE AS NOW MODELED
THEN SNOW TOTALS WILL BE MARKEDLY LESS BUT AS IT STANDS NOW...
WHILE THE OVERALL SNOW EVENT WILL NOT BE CONSIDERED ANYTHING SPECIAL...
ITS ACCUMULATION WITHIN A RELATIVELY SHORT PERIOD OF TIME MAKES THIS
MUCH HIGHER IMPACT.
FROM THE EARLIER DISCUSSION BELOW
THE OPEN/STABLE WAVE CONTINUES TO TRUCK ALONG THE STALLING
FRONTAL BOUNDARY TO THE SOUTH OF THE REGION TOMORROW MORNING.
THE NEW 12Z MODELS ARE IN AND THE UPPER AIR INITIALIZATION SHOWS
THEY ARE ALL A TAD DEEPER WITH THE SHORTWAVE ACROSS THE TEXAS
PANHANDLE AND COLDER IN THE LOW-LEVELS UPSTREAM...THIS WILL CAUSE A
GREATER UNCERTAINTY TO PTYPE TRANSITION KEEPING THE COLDER AIR
FURTHER WEST FOR A LONGER PERIOD OF TIME. FROM THE WORDS OF A FAMOUS
WEATHERMAN, "IT`S GON` RAIN, SLEET, SNOW"!, JUST A MATTER OF
LOCATION AND TIMING NOW.
ALL THE MODELS TAKE A SIMILAR TRACK WITH THE MID-LEVEL FEATURE AND
THE SURFACE INFLECTION. FOR THE MOST PART THE NEW GUIDANCE PAINTS A
PRETTY HEFTY AMOUNT OF QPF ACROSS THE REGION WITH A BAND OF NEARLY
EIGHT TENTHS FROM PHILLY SOUTHWARD, WHERE WE GET CLOSER TO AN INCH.
THE BIGGEST ISSUE WITH THIS SYSTEM, AS MENTIONED ABOVE, IS THE
LOW-LEVEL TEMPERATURES, INCLUDING THE BOUNDARY LAYER. THE FRONT THAT
WILL INCH THROUGH TONIGHT DOES NOT APPEAR TO BE A TRUE ARCTIC FRONT
AS TEMPERATURES BEHIND IT HAVE NOT PLUMMETED AS FAST AS THEY WOULD
OTHERWISE.
THE NAM HAS BEEN SLOWLY MOVING ITS BETTER FGEN FORCING FURTHER TO
THE SOUTH THE PAST COUPLE OF RUNS WHILE THE GFS KEEPS IT NEARBY,
MOSTLY OVER PHL. BUFKIT SOUNDINGS SHOW THE BEST SNOW GROWTH HAPPENS
LATE MORNING WHEN HELP FROM THE JET DYNAMICS PROPELS THE VVS
STRONGER AND THE BEST OMEGA MOVES IN PLACE. THIS IS WHEN THE BETTER
ACCUMULATING SNOWFALL WILL OCCUR AND THERE COULD BE SOME RATES
AROUND AN 1 OR 2 AN HOUR. THAT BEING SAID, THIS SYSTEM IS NOT
LOLLY-GAGGING DOWN TO FIRST, AS IT IT RAPIDLY PULLING AWAY SO ANY
BANDING THAT TAKE PLACE WILL BE TRANSIENT. WILL HAVE TO KEEP AN EYE
ON HOW THE RAIN/SNOW LINE PROGRESSES TONIGHT AND TOMORROW MORNING
AND WE COULD COME CLOSE TO WARNING AMOUNTS OUTSIDE THE CURRENT
WARNING AREAS.
THE SYSTEM MOVES OFFSHORE BY THE AFTERNOON HOURS AND PULLS TOWARDS
THE EAST-NORTHEAST PUTTING AN END TO THE SNOW BY THE LATE AFTERNOON
HOURS. TEMPERATURES SHOULD REMAIN RELATIVELY STEADY UNDER THE
INITIAL SNOWFALL AND THEN DROP ONCE THE HEAVIER QPF KICKS IN. THE
DAYTIME HIGH SHOULD BE REACHED SHORTLY AFTER MIDNIGHT TONIGHT AND
THE LOW SHOULD OCCUR LATE TOMORROW EVENING.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
LONG TERM PERIODS ARE STILL FOCUSED ON TWO MAIN EVENTS.
FIRST...THE LOW LIFTING NE TUESDAY NIGHT INTO WEDNESDAY. THE BIGGEST
QUESTION WITH THIS SYSTEM WILL BE THE TRACK OF THE LOW. IF THE TRACK
IS JUST SOUTH OF THE REGION...ON SHORE FLOW IN THE COLD SECTOR COULD
RESULT IN WIDESPREAD ICING. IF THE TRACK IS BISECTING OUR REGION AS
INDICATED BY THE GFS...THE ICING CONCERNS WILL BE PRIMARILY CONFINED
TO THE HIGHER TERRAIN IN EASTERN PA...WITH MOSTLY RAIN EXPECTED FROM
THE DELAWARE RIVER VALLEY AND EAST. THIS WILL BE HARD TO RESOLVE
WITH MUCH CONFIDENCE AT THIS TIME...ESPECIALLY GIVEN HOW POORLY SOME
MODELS INITIALIZED TODAY WITH FEATURES IN THE NEAR TERM. MODEL
SOUNDINGS FROM BOTH SOLUTIONS WITH THE TRACK OF THE LOW SHOW THE
MOIST LAYER TOO SHALLOW FOR ANY SIGNIFICANT SNOW GROWTH REGION IN
THE CLOUD...WITH THE POSSIBLE EXCEPTION OF THE POCONOS. THE MAIN
COLD FRONT LOOKS TO PUSH THROUGH THE REGION AFTER MOST OF THE
PRECIPITATION HAS ENDED.
BY THURSDAY...FLOW ALOFT TRANSITIONS TO ZONAL AS A SURFACE RIDGE
BUILDS IN FROM THE WEST. IN THE WAKE OF THE COLD FRONT
HOWEVER...TEMPERATURES WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL.
THE LATTER PART OF THE LONG TERM PERIOD WILL BEGIN RELATIVELY QUIET,
BUT ON THE COLD SIDE, AS HIGH PRESSURE EXTENDS ACROSS THE REGION
FROM THURSDAY NIGHT THROUGH THE DAYTIME FRIDAY. FOR THE MOST PART,
WE USED WPC TEMP GUIDANCE FOR THIS TIME FRAME, WITH A FEW LOCAL
ADJUSTMENTS. MINIMUM TEMPERATURES THURSDAY NIGHT ARE EXPECTED TO
MOSTLY BE IN THE TEENS ACROSS THE FORECAST AREA, WITH HIGH
TEMPERATURES FRIDAY MAINLY RANGING FROM THE MID 20S NORTH TO THE MID
30S SOUTH.
INTO NEXT WEEKEND, THE OVERALL PATTERN LOOKS MORE ACTIVE, WITH
ANOTHER STORM SYSTEM AFFECTING THE REGION AS HIGH PRESSURE MOVES
AWAY TO THE NORTHEAST. THERE ARE SOME NOTICEABLE DIFFERENCES IN
MODEL SOLUTIONS FOR NEXT WEEKEND, INCLUDING BETWEEN THE ECMWF AND
GFS. IN GENERAL, WE FAVORED THE ECMWF A LITTLE MORE AT THIS TIME,
BUT WE HOPE TO SEE MORE CONSISTENCY IN MODEL SOLUTIONS AS WE GET
CLOSER IN TIME TO REFINE THE DETAILS RELATED TO THIS STORM SYSTEM.
DEPENDING ON STORM TRACK AND TIMING, THIS LOOKS TO BE ANOTHER MIXED
PRECIPITATION EVENT FOR SATURDAY INTO SUNDAY, CREATING THE POTENTIAL
FOR HAZARDOUS TRAVEL.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE CEILINGS WILL GRADUALLY LOWER TO MVFR LATE AS LOW
PRESSURE APPROACHES FROM THE SOUTHWEST. THE PRECIPITATION TYPES
PRIOR TO DAYBREAK MONDAY SHOULD FEATURE RAIN, WET SNOW AND PERHAPS
SOME SLEET. THIS HAS BEEN ADDED WITH THE 12Z TAF ISSUANCE, AND
CONFIDENCE REGARDING THE START TIME IS AVERAGE. WE DID NOT INCLUDE
SLEET AT THIS TIME GIVEN LOWER CONFIDENCE OF THIS OCCURRENCE.
NORTHWEST WINDS 5 KNOTS OR LESS WILL SHIFT TO THE NORTH- NORTHEAST
AT 5-10 KNOTS OVERNIGHT. THE BIGGEST CHANGE BETWEEN THE 12 AND 18Z
TAFS IS THAT THE LATEST GUIDANCE IS SHOWING A SLIGHTLY WARMER
TEMPERATURE PROFILE ESPECIALLY FOR KPNE AND LOCATIONS FURTHER
SOUTH. THUS...HAVE PUSHED BACK THE TRANSITIONS OF PRECIPITATION
TYPE BY TWO HOURS FOR MOST OF THESE TERMINALS TO REFLECT THIS
CHANGE. WIDESPREAD MVFR...AND IFR CONDITIONS ARE EXPECTED IN SN
OR RASN. THE PRIMARY IMPACTS WILL BE THROUGH MID DAY...WITH
PRECIPITATION EXITING THE REGION LATER MONDAY AFTERNOON. N-NE
WIND GUST 15 TO 20 KT.
OUTLOOK...
TUESDAY...MAINLY VFR THROUGH THE DAY. MVFR CONDITIONS WITH RA FOR
KPHL...KPNE...KTTN...KILG...KMIV...AND KACY WILL BE POSSIBLE TUESDAY
NIGHT INTO WEDNESDAY. AT KRDG AND KABE...EXPECT FZRA REDUCING
VISIBILITIES AND CEILINGS TO MVFR...OR POSSIBLY IFR.
WEDNESDAY...MAINLY MVFR WITH THE PRECIPITATION WHICH WILL BE ENDING
LATE IN THE DAY...THEN VFR. FZRA SHOULD TRANSITION TO RA MID DAY
WEDNESDAY AT KRDG AND KABE.
THURSDAY...PRIMARILY VFR EXPECTED.
FRIDAY...PRIMARILY VFR EXPECTED.
&&
.MARINE...
THE CONDITIONS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH TONIGHT. A WEAKENING COLD FRONT WILL BE ARRIVING
THROUGH TODAY, HOWEVER IT SHOULD TEND TO STALL FOR A TIME AS IT
NEARS THE COAST. THIS WILL RESULT IN THE SOUTHERLY FLOW TURNING
MORE WESTERLY TOWARD EVENING. THERE WILL BE SOME FOG EARLY THIS
MORNING, HOWEVER MOST OF IT SHOULD BE CLOSER TO THE COAST AND
MAINLY FROM THE COAST OF NORTHERN OCEAN COUNTY ON NORTHWARD. THE
FLOW WILL THEN SHIFT TO THE NORTHWEST AND NORTH TONIGHT AS OUR
NEXT STORM SYSTEM APPROACHES. SEAS GENERALLY RUNNING AROUND 3 FEET
ON THE OCEAN AND 1 TO 2 FEET ON DELAWARE BAY.
OUTLOOK...
TUESDAY...SUB-SCA CONDITIONS EXPECTED.
WEDNESDAY...WINDS AND SEAS EXPECTED TO REACH SCA CONDITIONS AS A LOW
MOVES TOWARDS THE REGION.
THURSDAY...SUB-SCA CONDITIONS EXPECTED.
FRIDAY...SUB-SCA CONDITIONS EXPECTED.
&&
.HYDROLOGY...
CURRENT RIVER ICE CONDITIONS...ALL RIVERS IN THE HSA REPORT AT LEAST
SOME ICE COVER, WITH MANY COMPLETELY ICE COVERED. MANY GAGE READINGS
SHOW ICE EFFECTS.
ICE JAMS...SOLID ICE COVER IS NOT NECESSARILY AN ICE JAM. AN ICE JAM
IS DEFINED AS A RESTRICTION. IF WATER IF FLOWING UNDERNEATH THE ICE,
AND NOT CAUSING THE WATER TO BACK UP, THE ICE COVER IS NOT CONSIDERED
A JAM.
ICE BREAK UP...THE TWO MAIN FACTORS THAT QUICKLY CAUSE ICE TO BREAK
UP ARE RUNOFF AND TEMPERATURES, WITH RUNOFF BEING A MORE SIGNIFICANT
FACTOR. WHEN WATER LEVELS RISE, IT LIFTS THE ICE, FRACTURES IT, AND
DISLODGES IT FROM THE RIVER BANKS.
SO LET`S TAKE A LOOK AT TEMPERATURES AND RAINFALL(WHICH LEADS TO
RUNOFF).
TEMPERATURES...
MONDAY...LOWS IN THE HIGH TEENS TO AROUND 30. HIGHS IN THE UPPER
20S TO UPPER 30S.
TUESDAY...LOWS IN THE TEENS TO MID 20S. HIGHS IN THE 30S TO LOW
40S.
WEDNESDAY...LOWS IN THE MID 20S TO MID 30S. HIGHS IN THE 30S
AND 40S.
RAINFALL...THERE IS A CHANCE OF PRECIPITATION (MOSTLY RAIN)
TUESDAY NIGHT INTO WEDNESDAY. IT COULD START OFF AS SNOW AND ICE
FOR THE NORTHERN HALF OF HSA. EARLY QPF VALUES LATE TUESDAY INTO
WEDNESDAY ARE IN EXCESS OF 1.00 INCH WHICH WOULD CAUSE SIGNIFICANT
RUNOFF.
FUTURE ICE CONDITIONS...WHILE ICE RELEASES AND POSSIBLE JAMS ARE
HARD TO PREDICT, WE FEEL WITHOUT ANY SIGNIFICANT RUNOFF THIS WEEKEND,
THE WARMER DAYTIME TEMPERATURES ALONE WILL NOT BREAK UP THE ICE.
INSTEAD, WE FEEL THE ICE WILL SOFTEN AND MELT.
AT THIS TIME, THERE IS MORE OF A CONCERN FOR THE MIDDLE OF NEXT WEEK
AS DAYTIME HIGHS ARE FORECAST TO CLIMB ABOVE FREEZING AND A HEAVIER
RAINFALL IS EXPECTED TO MOVE INTO THE AREA.
STILL, BECAUSE RIVER ICE IS UNPREDICTABLE, PLEASE CONTINUE TO
MONITOR YOUR NEARBY STREAMS AND RIVERS AND NOTIFY THE APPROPRIATE
PERSONNEL IF YOU SHOULD SEE ANY FLOODING AND/OR AN ICE JAM OCCURRING.
&&
.CLIMATE...
THE CLIS FOR 2/2/14 WILL HAVE THE 12Z SNOW DEPTH ADDED AT 130AM EST
MONDAY.
RECORD DAILY SNOWFALL: WHILE NOT FORECAST ...THERE IS A SMALL CHANCE
ONE OR 2 OF THESE VALUES "MAY" BE APPROACHED TO WITHIN 1 INCH.
FEBRUARY 3
KABE 7.3 1961
KACY 4.2 1961
KPHL 8.0 1886
KILG 6.7 1961
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY FROM 6 AM TO 7 PM EST MONDAY FOR
PAZ054-055-060>062-101-103-105.
WINTER STORM WARNING FROM 6 AM TO 7 PM EST MONDAY FOR PAZ070-
071-102-104-106.
NJ...WINTER WEATHER ADVISORY FROM 6 AM TO 7 PM EST MONDAY FOR
NJZ001-007>010-012>015.
WINTER STORM WARNING FROM 6 AM TO 7 PM EST MONDAY FOR
NJZ016>020-026-027.
DE...WINTER STORM WARNING FROM 6 AM TO 7 PM EST MONDAY FOR DEZ001.
MD...WINTER STORM WARNING FROM 6 AM TO 7 PM EST MONDAY FOR MDZ008.
MARINE...NONE.
&&
$$
SYNOPSIS...JOHNSON
NEAR TERM...DRAG/HEAVENER 555
SHORT TERM...DRAG/HEAVENER 555
LONG TERM...JOHNSON/KLINE
AVIATION...JOHNSON/KLINE
MARINE...HEAVENER/JOHNSON/KLINE
HYDROLOGY...
CLIMATE...555
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1234 PM EST SUN FEB 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 453 AM EST SUN FEB 2 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY INTO THE CNTRL CONUS. AN ELONGATED SHORTWAVE TROUGH
FROM SOUTH OF JAMES BAY TO SRN MN BOOSTING 850-700 MB RH AND
INVERSION HEIGHTS TO 5K-6K FT BROUGHT AN INCREASE IN LES ACROSS ERN
LAKE SUPERIOR. THE HEAVIEST SNOW WAS MOVING INTO NRN LUCE COUNTY
WHERE THE WAS THE GREATEST AMOUNT OF OPEN WATER UPSTREAM. FARTHER
WEST...SOME MODERATE NW FLOW LES HAD ALSO DEVELOPED OFFSHORE FROM
MARQUETTE COUNTY WHERE THERE SEEMED TO BE ENOUGH GAPS IN THE ICE
COVER SO THAT LAND BREEZES COULD SUPPORT STRONGER LOW LEVEL CONV.
THE AMOUNT OF ICE COVER OVER WRN LAKE SUPERIOR IS EXTENSIVE ENOUGH
SO THAT ONLY LIGHT SNOW HAD DEVELOPED WITH LIMITED POTENTIAL FOR ANY
ACCUMULATIONS.
TODAY...EXPECT THE NW FLOW LES TO CONTINUE THROUGH THE MORNING WITH THE
POTENTIAL FOR A FEW INCHES OF ACCUMULATION NEAR THE SHORE EAST OF
MUNISING. SNOW AMOUNTS OF AN INCH OR LESS ARE EXPECTED BETWEEN
MARQUETTE AND MUNISING. AS WINDS BACK AND INVERSION HEIGHTS DROP THIS
AFTERNOON...THE LES SHOULD DIMINISH OVER THE NW AND LIFT OFF SHORE
FROM THE NE CWA.
TONIGHT...THE BEST FORCING WITH THE NEXT CLIPPER SHORTWAVE
REMAINS WELL TO THE NORTH OVER NRN ONTARIO. SOME LES WILL BE
POSSIBLE EARLY OVER NE LUCE COUNTY BEFORE WINDS BACK TO THE SW AND
PUSH THE SNOW BANDS OFFSHORE. WITH CLEARING OVERNIGHT...TEMPS WILL
DROP TO 5 BELOW TO 10 BELOW ZERO OVER THE INLAND WEST HALF OF UPPER
MICHIGAN. HOWEVER...WITH LIGHT WINDS ONLY AROUND 5 MPH...WIND CHILLS
WILL NOT BE SIGNFICANT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN FEB 2 2014
MODELS ARE IN GOOD AGREEMENT WITH BENIGN ZONAL FLOW UNTIL WED WHEN
MODEL TO MODEL DISAGREEMENT INCREASES SIGNIFICANTLY...BUT EVEN WITH
THE VARYING SOLUTIONS NO SIGNIFICANT PRECIP IS DEPICTED OVER THE
CWA.
A SYSTEM SIMILAR TO YESTERDAY IS SHOWN MOVING S OF THE CWA TUE INTO
TUE NIGHT...BUT THAT IS NOT EXPECTED TO BRING PRECIP TO THE CWA. THE
00Z/02 NAM IS THE ONLY MODEL FAR ENOUGH N WITH THE SYSTEM TO GIVE
PRECIP CHANCES IN THE CWA...SO THAT WAS CONSIDERED AN
OUTLIER...ESPECIALLY SINCE IT IS AT THE OF THE MODEL RUN. BESIDE
THAT SYSTEM...CONFIDENCE IS VERY LOW ON ANY OTHER SIGNIFICANT
SYSTEMS TO APPROACH THE AREA. WITH LACK OF CONFIDENCE FOR WED
THROUGH SAT AND GOOD AGREEMENT /BUT LACK OF SIGNIFICANT PRECIP/ MON
THROUGH TUE NIGHT...USED A CONSENSUS OF MODEL GUIDANCE FOR THE
FORECAST. TEMPERATURES OVER THE NEXT WEEK ARE EXPECTED TO BE SIMILAR
TO THE LAST WEEK OR SO WITH HIGHS IN THE SINGLE DIGITS AND TEENS
ABOVE ZERO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1233 PM EST SUN FEB 2 2014
IMPROVING CONDITIONS CONTINUE TO AFFECT THE TAF SITES AND THIS TREND
WILL PERSIST INTO MONDAY. COULD SEE A FEW FLURRIES AT TIMES WITH
MVFR TO LOWER VFR CIGS AT KCMX...BUT OTHERWISE SCT-BKN VFR CLOUDS
WILL AFFECT KIWD AND KSAW. WINDS WILL BE LIGHT THROUGH THE PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 453 AM EST SUN FEB 2 2014
A RELATIVELY QUIET PERIOD OF WEATHER IS EXPECTED FOR LAKE SUPERIOR.
GALES ARE NOT EXPECTED OVER THE NEXT SEVERAL DAYS. SOME PERIODS OF
FREEZING SPRAY WILL STILL OCCUR AT TIMES OVER ANY REMAINING OPEN
WATER AREAS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1206 PM CST SUN FEB 2 2014
.UPDATE...
ISSUED AT 728 AM CST SUN FEB 2 2014
WINDS HAVE INCREASED A BIT TO 4 OR 5 MPH WITH AMBIENT TEMPERATURES
AROUND -10F. SO A WIND CHILL ADVISORY IS IN PLACE UNTIL 16Z THIS
MORNING. A CHECK OF THE MESONET SUGGESTS LINCOLN COUNTY IS OKAY
AT THIS POINT WITH CALM WINDS AND TEMPS -5F TO -7F.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST SUN FEB 2 2014
TODAY AND TONIGHT...SOME TRAPPED MOISTURE HAS DEVELOPED IN THE
PLATTE VALLEY THIS MORNING PRODUCING A 100 FT CEILING AT NORTH
PLATTE. THIS THIN VEIL OF MOISTURE...IF IT PERSISTS...SHOULD MIX OUT
AFTER SUNRISE. THE RAP HAS MISPLACED THIS MOISTURE FURTHER NORTH AND
WEST ACROSS THE CHEYENNE DIVIDE OVER THE SRN PANHANDLE. SFC OBS SHOW
THIS MOISTURE FARTHER SOUTH ACROSS NERN COLO. REGARDLESS...THE RAP
MOVES THIS MOISTURE EAST PRESUMABLY THRU SWRN NEB SOUTH OF
INTERSTATE 80. ITS POSSIBLE DENSE FOG MAY DEVELOP ALONG AND SOUTH OF
THE INTERSTATE BEFORE SUNRISE.
WIND CHILL READINGS ARE CLOSE TO -20F ACROSS THE SOUTH. IF WINDS CAN
INCREASE THEN A WIND CHILL ADVISORY WOULD BE NEEDED FOR A FEW HOURS
THIS MORNING.
OTHERWISE...THE ARCTIC HIGH CENTERED OVER THE SNOW FIELD COVERING
SWRN NEB...NRN KS AND ERN NEB IS FCST TO MOVE EAST INTO MO/IL BY
MONDAY MORNING. A WARM FRONT IS FCST TO DEVELOP ACROSS NRN NEB
TONIGHT AHEAD OF A VERY STRONG ARCTIC HIGH RIDGING FROM THE YUKON
SOUTH THROUGH THE NRN HIGH PLAINS. CLEAR SKIES ARE EXPECTED ACROSS
THE FCST AREA TODAY AND TONIGHT SUPPORTING HIGHS IN THE 20S ACROSS
THE SNOW FIELD SOUTH AND 30S ACROSS THE SNOW-FREE NORTH. THE WARM
FRONT SHOULD KEEP THE ATM WELL MIXED TONIGHT AND LOWS FOLLOW IN THE
SINGLE DIGITS SOUTH TO NEAR 10 ABOVE IN THE NORTH. THE MET GUIDANCE
SUGGESTED SUBZERO LOWS TONIGHT ACROSS THE SOUTH BUT THIS HAS BEEN
SET ASIDE FOR NOW. THE GEM REGIONAL MODEL SHOWS LOWS IN THE SINGLE
DIGITS AND THIS MODEL HAS BEEN VERIFYING THE BEST WITH THE ONGOING
TEMPERATURE FORECAST EARLY THIS MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CST SUN FEB 2 2014
12Z MONDAY AND BEYOND. THE FORECAST CONCERNS IN THE EXTENDED
PERIODS ARE BITTERLY COLD TEMPERATURES AND THE POTENTIAL FOR SNOW
LATE MONDAY THROUGH EARLY WEDNESDAY AND POSSIBLY AGAIN LATE WEEK
INTO THE WEEKEND.
MONDAY...THE MODELS ARE CONTINUING TO ADVERTISE MOISTURE RETURN IN
ADVANCE OF A SOUTHERN STREAM TROUGH ADVANCING ACROSS THE
DESERT SOUTHWEST. ISENTROPIC UPGLIDE AND OMEGA ASSOCIATED WITH A
140KT UPPER JET MAY TRIGGER SNOW PRODUCTION BY AFTERNOON...SPREADING
FROM SOUTHWEST TO NORTHEAST NEBRASKA. HOWEVER A BETTER
PRECIPITATION SIGNAL IS SHOWN EARLY ON TUESDAY AS DPVA ASSOCIATED
WITH THE SOUTHERN STREAM WAVE SPREADS EAST NORTHEAST AND EJECTS
ACROSS THE SOUTHERN PLAINS. SNOW IS EXPECTED TO BECOME WIDESPREAD
AFTER DAYLIGHT WITH THE HIGHEST CHANCES REMAINING ALONG OUR SOUTHERN
BORDERS. WILL CONTINUE TO TREND THE POP FORECAST UPWARD WITH THIS
FORECAST PACKAGE...WITH 50-60% POPS ALONG AND SOUTH OF I80 TUESDAY.
DESPITE THE INCREASE IN POPS...WILL NOT VENTURE MUCH HIGHER WITH
EXPECTED QPF AS MODEL CONSENSUS INDICATES ~0.15" ACROSS OUR
SOUTH...AND LESS THAN A TENTH OF AN INCH FOR THE NORTHERN
SANDHILLS. SNOW PRODUCTION WILL BE ABOVE CLIMO NORMS AS PROXIMITY
SOUNDINGS INDICATE A DEEP DENDRITIC GROWTH ZONE...SO DESPITE
SOMEWHAT LIMITED MOISTURE...A FEW INCHES OF SNOW MAY BE POSSIBLE
GIVEN A 15:1 /OR HIGHER/ SLR. FORCING SPREADS TO THE EAST EARLY
WEDNESDAY WITH ONLY LIGHT SNOW REMAINING...WILL LIMIT POPS TO LOW
END CHANCE DURING THE DAY. BEYOND WEDNESDAY PRECIPITATION CHANCES
BECOME LIMITED TO OUR FAR SOUTHWEST WITH THE UPPER LEVELS
TRANSITIONING TO ZONAL. THERE IS HOWEVER A BETTER PRECIPITATION
SIGNAL LATE IN THE WEEK/EARLY NEXT WEEKEND WITH THE DEVELOPMENT OF
THE NEXT WESTERN CONUS TROUGH. BOTH THE EC AND GFS...WITH SUPPORT
FROM THE ENSEMBLES SUPPORT THIS LATE WEEK SYSTEM...THUS SLIGHT
CHANCE POPS ARE WARRANTED FOR NOW.
CONCERNING TEMPERATURES...ARCTIC AIR BEHIND A STRONG COLD FRONT WILL
INFILTRATE THE REGION LATE MONDAY AND REMAIN THROUGH MUCH OF THE
EXTENDED PERIODS. TUESDAY WILL BE MUCH COLDER AS H85 TEMPERATURES
FALL TO MINUS 20 OR COLDER FOR MUCH OF THE REGION. HIGHS SHOULD TOP
OUT ONLY IN THE TEENS...WITH THE POTENTIAL OF SINGLE DIGIT HIGHS FOR
OUR NORTH. COLDER YET FOR WEDNESDAY WITH ALL LOCATIONS ACROSS THE
FORECAST AREA STRUGGLING TO REACH THE UPPER SINGLE DIGITS. HIGHS
THURSDAY AND FRIDAY WILL WARM A FEW DEGREES EACH DAY AS WEAK RETURN
FLOW TRIES TO BECOME ESTABLISHED ACROSS THE HIGH PLAINS. LOWS
WEDNESDAY...THURSDAY AND QUITE POSSIBLY FRIDAY MORNING SHOULD BE
BELOW ZERO AS THE ARCTIC HIGH SETTLES ACROSS THE HIGH PLAINS. NOTE
THAT IF ADDITIONAL FRESH SNOW WERE TO ADD TO THE SNOWPACK...THE
DETERMINISTIC GUIDANCE WOULD BE ANOMALOUSLY TOO WARM...THIS MAY BE A
CASE WHERE SOME LOCATIONS SEE THE COLDEST READINGS OF THE SEASON.
WITH THE BITTERLY COLD TEMPERATURES EXPECTED DURING THE OVERNIGHT
ANY AMOUNT OF WIND WOULD ALLOW FOR CRITICALLY LOW WIND CHILL
READINGS. WIND CHILL ADVISORIES MAY BE NEEDED WEDNESDAY AND
THURSDAY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1202 PM CST SUN FEB 2 2014
HIGH PRESSURE ALOFT WILL BRING CLEAR SKIES AND VFR CONDITIONS TO
THE AREA THIS AFTERNOON AND EVENING. WINDS WILL BE SOUTHWEST AT 10
KTS THIS AFTERNOON...BECOMING LIGHT AND VARIABLE TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
317 PM EST SUN FEB 2 2014
.SYNOPSIS...
OTHER THAN LINGERING CLOUDS AND A FEW SPRINKLES OR SNOW SHOWERS
THIS EVENING...HIGH PRESSURE BUILDING SLOWLY EAST AND SOUTH INTO
THE REGION WILL PROVIDE MAINLY DRY WEATHER THROUGH TUESDAY WITH A
RETURN TO SEASONABLY COOL TEMPERATURES. BY LATER TUESDAY NIGHT INTO
WEDNESDAY A WIDESPREAD LIGHT TO MODERATE SNOWFALL WILL AFFECT THE
AREA AS LOW PRESSURE SKIRTS JUST SOUTH OF NEW ENGLAND. DRY AND COLD
WEATHER THEN RETURNS FROM THURSDAY ONWARD WITH THE POTENTIAL FOR
ANOTHER MORE SIGNIFICANT SYSTEM BY LATER NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 320 PM EST SUNDAY...A GENERALLY QUIET NIGHT ON TAP FOR THE
AREA AS SURFACE COLD FRONT SAGS SLOWLY SOUTHWARD INTO THE NORTHERN
MID ATLANTIC/SOUTHERN NEW ENGLAND WHILE LARGE-SCALE HIGH PRESSURE
AT THE SURFACE AND ALOFT BUILDS EAST FROM THE GREAT LAKES/SOUTHERN
CANADA. WITH MID TO UPPER LEVEL FLOW REMAINING SOUTHWESTERLY THE
FRONT WILL BE SLOW TO CLEAR SOUTH SO PLENTY OF CLOUDS AND SOME
LINGERING LIGHT SPRINKLES AND/OR SNOW SHOWERS WILL STILL BE
POSSIBLE THROUGH THE EVENING HOURS BEFORE BOUNDARY LAYER BEINGS TO
DRY OUT MORE CONSIDERABLY LATER TONIGHT. HIGHEST THREAT OF ANY
PCPN WILL BE ACROSS OUR SOUTHERN VT COUNTIES...ESPECIALLY IN THE
HIGHER TERRAIN...THOUGH ANY ACCUMULATIONS WILL BE LIGHT AT BEST.
GIVEN THE PREVALENCE OF CLOUDS THROUGH A GOOD PART OF THE NIGHT
LEANED ON THE WARMER SIDE OF GUIDANCE SHOWING MIN TEMPS IN THE 12
TO 22 RANGE WITH MILDEST READINGS CENTRAL/SOUTH AND COLDEST FAR
NORTH WHERE PARTIAL CLEARING WILL BE LIKELY LATE. WINDS LIGHT
NORTHERLY TO NEARLY CALM.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 320 PM EST SUNDAY...BROAD SURFACE HIGH PRESSURE WILL THEN
SETTLE ACROSS THE AREA BY MONDAY INTO TUESDAY WITH CLEAR TO PARTLY
CLOUDY SKIES AND A RETURN TO SEASONABLY COLD TEMPERATURES. WINDS
ALOFT GENERALLY ZONAL/WESTERLY SO NOT LOOKING AT ANYTHING
RESEMBLING THE COLD SURGES OF LAST MONTH...BUT NEAR SEASONAL
VALUES OF 20S TO AROUND 30 IN THE DAY AND 2 TO 12 ABOVE AT NIGHT
LOOK FAIRLY REASONABLE AT THIS TIME. MOST VARIABILITY LIKELY TO
OCCUR MONDAY NIGHT WHEN CENTER OF HIGH BUILDS DIRECTLY OVERNIGHT
AND NOCTURNAL RADIATIVE EFECTS AND DEVELOPMENT OF SLOPE/DRAINAGE
FLOWS WILL BE LIKELY.
BY TUESDAY NIGHT LATEST SHORT AND MEDIUM RANGE MODELS MAINTAIN
REMARKABLE CONSISTENCY IN SHOWING A FAIRLY ROBUST SOUTHERN STREAM
SYSTEM LIFTING NORTHEAST FROM THE LOWER MISSISSIPPI RIVER VALLEY
INTO THE MID ATLANTIC/NORTHEAST. CONFLUENT FLOW ACROSS OUR AREA
SHOULD ENSURE THE SYSTEM WILL BE FAIRLY PROGRESSIVE...BUT EVIDENCE
CONTINUES TO SUGGEST IT WILL BE ACCOMPANIED BY AN AMPLE GOMEX
MOISTURE PLUME. THERMAL PROGS ALSO REMAIN PLENTY COLD SO PRIOR IDEA
OF WIDESPREAD LIGHT TO MODERATE SNOW OVERSPREADING OUR AREA FROM
THE SOUTH LATER TUESDAY NIGHT STILL LOOKS RIGHT ON TRACK WITH SOME
MINOR ACCUMULATIONS LIKELY ALREADY ON THE GROUND BY SUNRISE..ESP
SOUTH. WITH LIGHT WINDS AND INCREASING CLOUDS TEMPERATURES WILL
HOLD IN THE TEENS TO LOWER 20S FOR MOST SPOTS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 320 PM EST SUNDAY...WIDESPREAD ACCUMULATING SNOW EVENT WL
IMPACT OUR CWA WEDS INTO WEDS NIGHT. OVERALL...LATEST 12Z GUIDANCE
IS VERY SIMILAR TO LAST NIGHT`S 00Z AND YESTERDAY`S 12Z RUNS WITH
EXCELLENT RUN TO RUN CONSISTENCY AND BLW AVERAGE
SPREAD...RESULTING IN ABOVE ABOVE FORECASTER CONFIDENCE FOR
UPCOMING SNOW EVENT.
SYNOPTIC SCALE SHOWS MID/UPPER LVL TROF ACRS THE WESTERN CONUS WL
PROGRESS EAST ON TUESDAY...WHILE POTENT 5H VORT HELPS IN THE
DEVELOPMENT OF SFC LOW PRES ACRS THE MS RIVER VALLEY. THIS SFC LOW
PRES IS PROGGED TO TRACK FROM WESTERN TN ON 00Z WEDS TO PITTSBURGH
PA BY 12Z WEDS AND JUST SOUTH OF CAPE COD BY 00Z THURS. THE
GFS/ECMWF/GEM AND LATEST 12Z GFS ENSEMBLE DATA SUPPORTS THIS
TRACK...WHILE 15Z SREF AND 12Z NAM ARE 50 TO 75 MILES FURTHER NORTH
AND SHOW MORE LIFT/MOISTURE AND QPF ACRS OUR CWA. THE CONVECTION
ALONG THE GULF COAST STATES ON TUES WL NEED TO BE WATCHED CLOSELY
FOR POSSIBLE BUILDING OF STRONGER DOWNSTREAM RIDGE ACRS THE SE CONUS...RESULTING
IN A SLIGHTLY FURTHER NORTH TRACK OF SFC LOW PRES. WL KEEP TWD
CONSISTENCY BUT BLEND SOME SREF/NAM QPF FIELDS INTO OUR
GRIDS...WHICH SHOWS AMOUNTS BTWN 0.10 AND 0.25 INTERNATIONAL
BORDER TO 0.50 TO 0.75" RUTLAND/WINDSOR COUNTIES. SNOW
ACCUMULATIONS WL RANGE FROM 1 TO 3 INCHES NORTH TO 6 TO 12 INCHES
SOUTH...WITH DACKS INTO CENTRAL VT GETTING 3 TO 9 INCHES AT FIRST
GUESS. THIS WL BE SUBJECT TO CHANGE...AS ANY SHIFT IN THE TRACK WL
HAVE IMPACTS ON QPF/SNOWFALL.
GIVEN THE POSITION OF MID/UPPER LVL TROF ACRS EASTERN CANADA AND
LOCATION OF BERMUDA HIGH TYPE FEATURE IN THE CENTRAL ATLANTIC...WL
RESULT IN A VERY FAST PROGRESSIVE FLW ACRS THE EASTERN CONUS THRU
DAY 7 AND NO CLOSED 7H/5H CIRCULATION FOR UPCOMING SYSTEM ON WEDS.
IN ADDITION...BOTH NAM/GFS SHOW PROGGED 25H POLAR JET OF 180 TO
200 KNOTS ACRS SOUTHERN CANADA...WHICH INITIALLY WL HELP WITH
LARGE SCALE SYNOPTIC LIFT...BUT AT THE SAME TIME KEEPS SYSTEM VERY
PROGRESSIVE. GFS SHOWS BEST PWS OF >0.50" LOCATED ACRS SOUTHERN
NEW ENGLAND NOW...ALONG WITH STRONG 850 TO 700MB FGEN FORCING AND
LLVL THETA E CONVERGENCE. ALSO...HAVE NOTED STRONGEST CORE OF 85H
WINDS MOVE FROM SOUTHERN PA TO SOUTH OF LONG ISLAND DURING THE
EVENT...WITH BEST DEEP LAYER MOISTURE CONVERGENCE JUST SOUTH OF
OUR CWA. HOWEVER...STILL PLENTY OF 850 TO 500MB RH AVAILABLE ACRS
OUR CWA...ALONG WITH STRONG DEEP LAYER LIFT FROM POTENT 5H VORT
MOVING DIRECTLY OVERHEAD...RESULTING IN A PERIOD OF ACCUMULATING
SNOWFALL. THINKING HEAVIEST SNOW OCCURS EARLY WEDS MORNING AND
TAPERS OFF BY LATE AFTN/EARLY EVENING ON WEDS. SOUNDING PROFILES
SUPPORT A MODERATE FLUFF FACTOR WITH RATIOS AROUND 12 TO 1 VALLEYS
AND 16 TO 1 ABOVE 1500 FEET FOR WEDS. PROGGED 85H TEMPS BTWN -10C
AND -12C SUPPORT HIGHS TEENS MTNS TO 20S VALLEYS ON WEDS.
FOR THURS INTO FRIDAY...FAST CONFLUENT FLW ALOFT CONTS WITH BROAD
SFC HIGH PRES EXTENDING FROM THE CENTRAL PLAINS INTO THE NE CONUS.
THIS WL RESULT IN MAINLY DRY CONDITIONS WITH COOL NIGHTS AND
SEASONABLE DAYTIME HIGHS. A WEAK 5H VORT MAY PRODUCE A FEW MTN
SNOW SHOWERS ON FRIDAY. NEXT LARGE SCALE SYNOPTIC SYSTEM ARRIVES
LATE SAT INTO SUNDAY WITH ANOTHER CHC FOR SNOW. BOTH GFS/ECWMF
SHOW PLENTY OF DEEP LAYER MOISTURE AVAILABLE WITH PROGRESSIVE
MID/UPPER LVL PATTERN CONTINUING. STILL SOME UNCERTAINTY TO TRACK
OF SFC LOW PRES AND MAGNITUDE OF 5H/7H TROF AS SYSTEM EJECTS
FROM INTER MOUNTAIN WEST ON FRIDAY. WL MENTION CHC POPS LATE SAT
INTO SUNDAY AND FINE TUNE FCST AS EVENT BECOMES CLOSER.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...AVIATION CHALLENGE THRU THIS EVENING WL BE
POTENTIAL IFR CIGS AT RUT AND WHEN LOW CLOUD IFR CIGS LIFT AT SLK.
CRNT SFC ANALYSIS PLACES A WEAK COLD FRNT ACRS CENTRAL VT INTO
CENTRAL NY ATTM...WITH LATEST GOES IFR PROB SATL IMAGERY SHOWING
LIKELY IFR CIGS DEVELOPING ACRS THE SPINE OF THE GREEN MTNS AND
PARTS OF THE DACKS. THIS TREND COMBINED WITH LATEST RAP 13 AND
BTV6 SHOWING LLVL RH INCREASING AND LCL FALLING AT RUTLAND BLW
1000 FT SUPPORT IFR CIGS DEVELOPING BTWN 19Z-21Z TODAY. BTV WL
HAVE TO BE WATCHED CLOSELY FOR A PERIOD OF IFR CIGS THIS AFTN. IN
ADDITION...RADAR SHOWS SOME LIGHT RAIN/SNOW WHICH MAY IMPACT
RUT/MPV/SLK TAFS THRU THIS AFTN/EVENING. HAVE USED A TEMPO BTWN
20-24Z TO INDICATE IFR CIGS AND MVFR VIS IN -RASN. AT SLK WL USE
PREVAILING GROUP FOR IFR CIGS THRU 00Z...COULD SEE PERIODS OF MVFR
CIGS BTWN 19Z-21Z PER LATEST RAP13. ELSEWHERE...MAINLY MVFR
CONDITIONS WL PREVAIL WITH CIGS BTWN 1500 AND 2500 FEET...WITH
LIGHT NORTHWEST WINDS. AS SFC HIGH PRES BUILDS INTO OUR
REGION...LLVL DRYING WL OCCUR AND BRING A RETURN TO VFR CONDITIONS
BY MONDAY.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...SFC HIGH PRES WITH VFR
CONDITIONS WL PREVAIL FROM 18Z MONDAY THRU 06Z WEDS. A BRIEF
PERIOD OF MVFR VIS IN HZ/BR IS POSSIBLE AT SLK TUESDAY MORNING
ASSOCIATED WITH LIGHT WINDS AND CLR SKIES. OTHERWISE...WIDESPREAD
SNOW DEVELOPS BTWN 09Z-12Z WEDS WITH IFR AND LOCALLY LIFR
CONDITIONS LIKELY WITH VIS BLW 1SM AND CIGS BTWN 1000 AND 2500 FT.
CLRING TREND WITH VFR CONDITIONS RETURN BY THURSDAY...AS SYSTEM
RACES NORTHEAST.
&&
.EQUIPMENT...
AS OF 710 PM EST SATURDAY...THE AUTOMATED SURFACE OBSERVING SYSTEM (ASOS)
AT THE KNAPP STATE AIRPORT IN BARRE-MONTPELIER VERMONT (KMPV) HAS
NOT TRANSMITTED AN OBSERVATION FROM THIS SITE SINCE 1551Z ON
FEBRUARY 1ST. THE FEDERAL AVIATION ADMINISTRATION (FAA) HAS
INFORMED THE NATIONAL WEATHER SERVICE THAT THIS IS DUE A TELEPHONE
COMMUNICATIONS LINE ISSUE. THERE IS NO ESTIMATE AVAILABLE AT THIS
TIME AS TO WHEN SERVICE WILL BE RESTORED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1251 PM EST SUN FEB 2 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED FRONT WILL CONTINUE MOVING
ACROSS THE NORTH COUNTRY TODAY BRINGING LIGHT PRECIPITATION TO THE
AREA...TAPERING OFF THIS AFTERNOON. HIGH PRESSURE BUILDS INTO THE
AREA TONIGHT AND REMAINS INTO TUESDAY. THIS WILL BE FOLLOWED BY A
COASTAL SYSTEM AFFECTING THE REGION MIDWEEK...WITH HIGH PRESSURE
RETURNING FOR THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 913 AM EST SUNDAY...MADE SOME WHOLESALE CHANGES TO POPS/WX AS
WE PROGRESS INTO TODAY/TONIGHT BASED OFF CURRENT OBSERVATIONAL
TRENDS. CURRENT ANALYSIS SHOWING SFC FRONT NOW SLOWLY PROGRESSING
SOUTHWARD ACROSS THE FCST AREA...WITH BEST MOISTURE NOW BECOMING
FOCUSED ACROSS THE SRN TIER OF NY INTO CENTRAL/SRN NEW ENGLAND.
FEEL WITH LATEST TRENDS IN THE BTV4 AND RAP PROGS...BEST FOCUS FOR
PCPN SHOULD OCCUR ACROSS OUR SOUTHERN ZONES TODAY...THOUGH CAN`T
RULE OUT SOME SCT LIGHT SPRINKLES/SHSN ACTIVITY ACROSS THE NORTH
AS NORTHWESTERLY FLOW AND MODEST COLD THERMAL ADVECTION ACT WITH
OROGRAPHIC EFFECTS. IN ALL CASES PCPN WILL BE LIGHT...HOWEVER BEST
SHOT OF ADDL ACCUMULATIONS AGAIN APPEAR TO BE ACROSS THE SOUTH
WHERE A DUSTING TO PERHAPS 2 INCHES WILL BE POSSIBLE...ESP HIGHER
TERRAIN OF THE SOUTHERN GREENS. ELSEWHERE AN INCH OR LESS AND
MAINLY HIGHER ELEV OF THE DACKS/NRN GREENS. WITH SFC FRONT SAGGING
THROUGH THE AREA...TEMPERATURES WILL EITHER HOLD NEARLY STEADY IN
THE CASE OF OUR SOUTHERN COUNTIES...OR GRADUALLY FALL THROUGH THE
DAY FOR CENTRAL/NRN AREAS. BY EARLY EVENING READINGS WILL RANGE
FROM THE UPPER 20S TO LOWER 30S NORTH...AND MID TO UPPER 30S SOUTH
UNDER LIGHT NORTH TO NORTHWESTERLY FLOW AS FRONT WILL HAVE CLEARED
SOUTH.
BY TONIGHT ANY LINGERING FLURRIES/LIGHT SHSN WILL BE ENDING AS SFC
HIGH PRESSURE GRADUALLY BUILDS EAST FROM SC CANADA/GREAT LAKES.
EXPECT BEST SHOT OF CLEARING TO OCCUR IN THE NORTHERN VALLEY AND
PERHAPS NRN MTNS...WITH AT LEAST SOME LINGERING CLOUD COVER SOUTH.
LOWS BY MONDAY MORNING 5 TO 15 ABOVE NORTH AND HIGHLY DEPENDENT ON
AMT OF CLEARING...AND GENERALLY 10 TO 15 ABOVE SOUTH.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH TUESDAY/...
AS OF 358 AM EST SUNDAY...FOR MONDAY THRU TUESDAY...SFC RIDGE WILL
BUILD OVER THE NORTHEAST REGION PROVIDING A NICE 48-HR...PRECIP-
FREE STRETCH. DO EXPECT DAYTIME TEMPS DURING THIS TIMEFRAME TO
REMAIN NEAR NORMAL FOR THIS TIME OF YEAR. CLR SKIES MONDAY NIGHT
WITH LIGHT WINDS WILL GIVE AREA STRONG RADIATIONAL COOLING...SO
WILL GO SLIGHTLY BLW NORMAL BY A DEGREE OR TWO AREA-WIDE.
OVERALL....HIGHS WILL RANGE IN THE 20S WITH SPOTS 30F IN THE
CVLY/LWR CT RIVER VALLEY. OVERNGT LOWS WILL RANGE MAINLY ZERO TO
10 ABV...WITH SOME NEG SINGLE NUMBERS IN THE DACKS AND FAR NE
KINGDOM.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EST SUNDAY...CONTINUE TO SEE GOOD CONSISTENCY BETWEEN
ECMWF AND GFS WITH THE 00Z CYCLE AND BELOW AVERAGE SPREAD IN 00Z
GFS ENSEMBLE MEMBERS KEEPING THE EXTENDED FCST RELATIVELY STABLE.
MAIN ISSUE WILL BE EXPECTED SNOWFALL DEVELOPING BETWEEN 06-12Z
WEDNESDAY AND LASTING THRU THE DAY. SRN STREAM SHORTWAVE TROUGH
EJECTING NEWD ACROSS THE MID-MS AND OHIO VALLEYS DURING TUESDAY
NIGHT WILL BE ASSOCIATED WITH A SFC LOW MOVING NEWD ACROSS THE
CENTRAL APPALACHIANS. THIS SFC LOW IS EXPECTED TO REDEVELOP OFF
THE NJ COAST DURING THE DAY WEDNESDAY...KEEPING LOW-LEVEL NELY TO
NLY FLOW ACROSS THE NORTH COUNTRY. CONTINUES TO APPEAR TO BE AN
ALL SNOW EVENT ACROSS THE REGION BASED ON 00Z ECMWF AND GFS TEMP
PROFILES. WE/VE DISREGARDED THE WARMER 00Z NAM AT THIS
POINT...WHICH TENDS TO HAVE POORER VERIFICATION OF PARENT SYNOPTIC
FEATURES TOWARD 84-HRS. LOW-LEVEL WAA AND QG FORCING ALLOWS SNOW
TO OVERSPREAD THE REGION FROM SW-NE LATE TUESDAY NIGHT...WITH
HEAVIEST QPF/SNOWFALL RATES EXPECTED THRU 18Z WEDNESDAY. 700MB
TROUGH REMAINS AN OPEN WAVE...THUS SYSTEM IS RELATIVELY QUICK
MOVING WITH SNOWFALL TAPERING OFF TO SNOW SHOWERS TOWARD WEDNESDAY
EVENING. GIVEN TRACK OF LOW OFF THE SRN NEW ENGLAND
COAST...ANTICIPATED HEAVIEST SNOWFALL WILL BE ACROSS
CENTRAL/S-CENTRAL VT. MODEL QPF FORECASTS RANGE FROM AROUND 0.25"
NEAR THE INTL BORDER UP TO 0.75" ACROSS SRN RUTLAND/WINDSOR
COUNTIES...WHICH APPEAR REASONABLE BASED ON PW VALUES AND SPEED OF
THE SYSTEM. IF THESE TRENDS HOLD...PROBABLY LOOKING AT A 6-10"
SNOWFALL ACROSS CENTRAL/S-CENTRAL VT WITH GENERALLY 3-6" IN THE
BTV AREA...NRN VT AND THE NORTHERN ADIRONDACKS. MAY SEE A BIT LESS
IN THE IMMEDIATE ST. LAWRENCE VALLEY FURTHEST REMOVED FROM
ANTICIPATED LOW TRACK. MAIN IMPACT WITH THIS SYSTEM WILL BE WITH
SNOW COVERED ROADWAYS AND POTENTIAL SLOW TRAVEL CONDITIONS FROM
THE PRE-DAWN HRS WEDNESDAY RIGHT THRU THE DAYLIGHT HRS. WE/LL
MENTION THIS POTENTIAL SYSTEM ONCE AGAIN IN THE MORNING HAZARDOUS
WEATHER OUTLOOK. HIGH TEMPERATURES ON WEDNESDAY ARE EXPECTED TO
BE IN THE MID-UPR 20S.
SYNOPTIC LOW DEPARTS QUICKLY EWD SOUTH OF NOVA SCOTIA DURING
WEDNESDAY NIGHT. MAY SEE A FEW LINGERING SNOW SHOWERS EARLY FOLLOWED
BY PARTIAL CLEARING DURING THE PRE-DAWN HRS THURSDAY. SFC RIDGE AXIS
WILL BE SHIFTING INTO NRN NY BY 12Z THU...SO MAY SEE SOME GOOD
RADIATIONAL COOLING TOWARD DAWN WITH THE EXPECTED FRESH SNOWPACK.
GENERALLY LOOKING AT LOW TEMPS IN THE SINGLE DIGITS ABOVE ZERO IF
CLEARING OCCURS AS EXPECTED.
GENERALLY FAIR CONDITIONS THU-SAT. A SECONDARY COLD FRONT PASSING
THRU FROM N-S FRIDAY NIGHT MAY BRING A FEW SCATTERED SNOW
SHOWERS...BUT CONDITIONS ARE OTHERWISE EXPECTED TO BE DRY WITH TEMPS
NEAR TO SLIGHTLY BELOW SEASONABLE LEVELS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...AVIATION CHALLENGE THRU THIS EVENING WL BE
POTENTIAL IFR CIGS AT RUT AND WHEN LOW CLOUD IFR CIGS LIFT AT SLK.
CRNT SFC ANALYSIS PLACES A WEAK COLD FRNT ACRS CENTRAL VT INTO
CENTRAL NY ATTM...WITH LATEST GOES IFR PROB SATL IMAGERY SHOWING
LIKELY IFR CIGS DEVELOPING ACRS THE SPINE OF THE GREEN MTNS AND
PARTS OF THE DACKS. THIS TREND COMBINED WITH LATEST RAP 13 AND
BTV6 SHOWING LLVL RH INCREASING AND LCL FALLING AT RUTLAND BLW
1000 FT SUPPORT IFR CIGS DEVELOPING BTWN 19Z-21Z TODAY. BTV WL
HAVE TO BE WATCHED CLOSELY FOR A PERIOD OF IFR CIGS THIS AFTN. IN
ADDITION...RADAR SHOWS SOME LIGHT RAIN/SNOW WHICH MAY IMPACT
RUT/MPV/SLK TAFS THRU THIS AFTN/EVENING. HAVE USED A TEMPO BTWN
20-24Z TO INDICATE IFR CIGS AND MVFR VIS IN -RASN. AT SLK WL USE
PREVAILING GROUP FOR IFR CIGS THRU 00Z...COULD SEE PERIODS OF MVFR
CIGS BTWN 19Z-21Z PER LATEST RAP13. ELSEWHERE...MAINLY MVFR
CONDITIONS WL PREVAIL WITH CIGS BTWN 1500 AND 2500 FEET...WITH
LIGHT NORTHWEST WINDS. AS SFC HIGH PRES BUILDS INTO OUR
REGION...LLVL DRYING WL OCCUR AND BRING A RETURN TO VFR CONDITIONS
BY MONDAY.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...SFC HIGH PRES WITH VFR
CONDITIONS WL PREVAIL FROM 18Z MONDAY THRU 06Z WEDS. A BRIEF
PERIOD OF MVFR VIS IN HZ/BR IS POSSIBLE AT SLK TUESDAY MORNING
ASSOCIATED WITH LIGHT WINDS AND CLR SKIES. OTHERWISE...WIDESPREAD
SNOW DEVELOPS BTWN 09Z-12Z WEDS WITH IFR AND LOCALLY LIFR
CONDITIONS LIKELY WITH VIS BLW 1SM AND CIGS BTWN 1000 AND 2500 FT.
CLRING TREND WITH VFR CONDITIONS RETURN BY THURSDAY...AS SYSTEM
RACES NORTHEAST.
&&
.EQUIPMENT...
AS OF 710 PM EST SATURDAY...THE AUTOMATED SURFACE OBSERVING SYSTEM (ASOS)
AT THE KNAPP STATE AIRPORT IN BARRE-MONTPELIER VERMONT (KMPV) HAS
NOT TRANSMITTED AN OBSERVATION FROM THIS SITE SINCE 1551Z ON
FEBRUARY 1ST. THE FEDERAL AVIATION ADMINISTRATION (FAA) HAS
INFORMED THE NATIONAL WEATHER SERVICE THAT THIS IS DUE A TELEPHONE
COMMUNICATIONS LINE ISSUE. THERE IS NO ESTIMATE AVAILABLE AT THIS
TIME AS TO WHEN SERVICE WILL BE RESTORED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JN
NEAR TERM...JMG
SHORT TERM...JN
LONG TERM...BANACOS
AVIATION...TABER
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
117 PM EST SUN FEB 2 2014
.SYNOPSIS...
A WARMING TREND TODAY WILL CONTINUE INTO MONDAY AS HIGH PRESSURE
SLIDES OFFSHORE. WEAK LOW PRESSURE WILL PASS NORTHWEST OF THE AREA
EARLY MONDAY. THIS LOW WILL DRAG A COLD FRONT ACROSS THE EASTERN
CAROLINAS MONDAY AFTERNOON. BEHIND THE FRONT HIGH PRESSURE WILL
BUILD DOWN THE COAST THROUGH TUESDAY. A STRONG COLD FRONT WILL
CROSS THE AREA WEDNESDAY NIGHT. COOL AND DRY HIGH PRESSURE WILL
BUILD IN THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM SUNDAY...LATEST SATELLITE IMAGERY AND SFC OBS
CONFIRM THAT THE LOW STRATUS AND FOG WILL CONTINUE TO DISSIPATE AS
WESTERLY WINDS HAVE PICKED UP AT THE SFC ALLOWING DRIER TO MIX IN.
BETWEEN 1 AND 2 PM...THE MAJORITY OF THE SKIES ACROSS THE FA WILL
OBSERVE MOSTLY SUNNY SKIES. HAVE UPPED THIS AFTN MAX TEMP BY 1 TO
2 CATEGORIES. EARLY FEB INSOLATION AND A WESTERLY WIND TO AID IN
PUSHING MAX TEMPS TODAY TO AT LEAST BETWEEN 65 AND 70 DEGREES. SEA
FOG HAS YET TO REALLY MATERIALIZE...ALONG WITH THE 60+ DEWPOINTS.
HAVE CANCELED THE DENSE SEA FOG ADV FOR THE ADJACENT ATL WATERS.
HOWEVER...HAVE KEPT PATCHES OF SEA ACROSS THE COASTAL WATERS THAT
COULD PARTIALLY MOVE ONSHORE BASED ON THE SSW-WSW LOW LEVEL
STEERING WINDS.
PREVIOUS DISCUSSION..................................
AS OF 630 AM SUNDAY...A 500 MB RIDGE WILL REMAIN PARKED OFF THE SE
COAST WHILE A SHORTWAVE CURRENTLY IN WEST TEXAS MOVES INTO THE
SOUTHERN APPALACHIANS LATE TONIGHT. HERE AT THE SURFACE THE OLD
ARCTIC FRONT THAT BROUGHT US COLD AND ICE LAST WEEK STALLED DOWN
OVER THE BAHAMAS FOR SEVERAL DAYS...BUT HAS RETURNED NORTH TO A
POSITION ABOUT 50-70 MILES OFF THE CAROLINA COAST. THIS BOUNDARY
WILL DISSIPATE LATER TODAY AS SOUTHWEST LOW-LEVEL FLOW STRENGTHENS
BETWEEN THE HIGH WELL OFFSHORE AND AN APPROACHING COLD FRONT FROM
THE NORTHWEST.
A COOL AND COMPLETELY SATURATED LOW-LEVEL AIRMASS HAS PRODUCED
PLENTY OF FOG AND LOW STRATUS THIS MORNING. MODEL FORECAST SOUNDINGS
INDICATE THE TOP OF THIS CLOUD DECK RANGES FROM 2000 FT AGL INLAND
TO NEARLY 10000 FT OVER ILM...BUT SHOULD THIN FROM THE TOP DOWN AS
THE DAY PROGRESSES. TIMING THE BREAKUP OF THESE LOW CLOUDS IS GOING
TO BE KEY TO GETTING CLOSE WITH HIGH TEMPERATURES TODAY. WITHOUT
CLOUDS THE AIRMASS ALOFT IS CAPABLE OF SUPPORTING HIGHS IN THE LOWER
70S QUITE EASILY. BEYOND 11:00 AM EVERY HOUR WE CAN MAINTAIN LOW
CLOUD COVER WILL CUT A COUPLE DEGREES OFF THAT POTENTIAL. I AM
TENTATIVELY FORECASTING HIGHS TO REACH 60-65 TODAY (WARMEST SOUTH OF
FLORENCE AND CONWAY) BUT WITH LOW CONFIDENCE. 06Z MODELS CONTINUE TO
SHOW THE SAME DIFFERENCES AS THEIR 00Z COUNTERPARTS WITH THE GFS
WARM AND NAM AND RUC MUCH COOLER. AS LIGHT WEST-NORTHWEST SURFACE
WINDS BECOME SOUTHWESTERLY LATE THIS MORNING...DEWPOINTS SHOULD
INCREASE ACROSS THE COASTAL WATERS WITH SEA FOG BECOMING MORE
PREVALENT. FOR AREAS WHERE A SOUTHWEST WIND IS ONSHORE (NE HORRY AND
BRUNSWICK COUNTIES) THIS MEANS CLOUDS AND FOG COULD PERSIST ALL
AFTERNOON WITH HIGHS PERHAPS STRUGGLING TO REACH THE MID 50S.
PLENTY OF LOW-LEVEL MOISTURE AND INITIALLY LIGHT WINDS TONIGHT
SHOULD ALLOW FOG AND LOW STRATUS TO REDEVELOP QUICKLY DURING THE
EVENING HOURS. THE APPROACHING SHORTWAVE DISTURBANCE COULD BRING
SCATTERED SHOWERS OR EVEN A THUNDERSTORM ACROSS THE NORTHERN
SECTIONS OF THE PEE DEE REGION LATE TONIGHT...MAINLY NORTH OF
FLORENCE AND MARION. THE REMAINDER OF THE AREA SHOULD REMAIN DRY.
LOWS SHOULD FALL TO 48-53...WARMEST NEAR THE SANTEE RIVER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...WEAK SURFACE WAVE PASSING WEST OF THE AREA
DURING MON WILL DRAG A COLD FRONT ACROSS THE EASTERN CAROLINAS LATE
IN THE DAY. AHEAD OF THE FRONT INCREASED MOISTURE AND DIURNAL
INSTABILITY WILL CREATE POTENTIAL FOR ISOLATED AFTERNOON SHOWERS.
ALTHOUGH LOW LEVEL JET DOES NOT APPEAR STRONG ENOUGH FOR SEVERE
WEATHER IT WILL ENHANCE BOUNDARY LAYER MOISTURE AND INSTABILITY.
FRONT PUSHES OFF THE COAST BY EARLY EVENING WITH HIGH PRESSURE
CENTERED OVER THE GREAT LAKES BUILDING SOUTH. COLD PUSH BEHIND THE
FRONT IS RATHER WEAK AND SURFACE BOUNDARY QUICKLY ENDS UP PARALLEL
TO STEERING FLOW. WEAK ISENTROPIC LIFT DEVELOPS AROUND MIDNIGHT AND
SLOWLY STRENGTHENS OVERNIGHT. ABUNDANT LOW LEVEL MOISTURE AND
AFOREMENTIONED ISENTROPIC LIFT RESULT IN LIGHT RAIN DEVELOPING OVER
THE AREA BY DAYBREAK TUE.
TUE WILL BE DOMINATED BY HIGH PRESSURE WEDGING DOWN THE COAST FROM
THE NORTHEAST. ISENTROPIC LIFT AND INCREASING MOISTURE WILL MAINTAIN
LOW OVERCAST AND INCREASE RAIN CHANCES DURING THE DAY. MEANWHILE
DURING THE DAY TUE A SOUTHERN STREAM SYSTEM EMERGING FROM THE
SOUTHWEST TRACKS NORTHEAST ACROSS THE LOWER MS VALLEY AND INTO THE
TN VALLEY TUE EVENING. AS THE SURFACE LOW MOVES INTO THE OH VALLEY
TUE NIGHT IT LIFTS THE STALLED FRONT/TROUGH OFF THE CAROLINA COAST
NORTH AS A WARM FRONT. STRONG WARM ADVECTION DEVELOPS TUE NIGHT WITH
TEMPS LIKELY RISING OVERNIGHT. TUE HIGHS...WHICH WILL END UP BELOW
CLIMO IN MOST PLACES...ARE LIKELY TO OCCUR LATE IN THE DAY. ALSO
WORTH NOTING THAT TUE HIGHS ARE LIKELY TO BE WITHIN A FEW DEGREES OF
TUE NIGHT LOWS. WEAK CONVECTION IS POSSIBLE IN THE WARM SECTOR TUE
NIGHT BUT SURFACE BASED INSTABILITY IS SOMEWHAT LIMITED. STILL THE
PRESENCE OF DEEPER MOISTURE AND INCREASING LOW LEVEL JET WARRANTS
CONTINUATION OF INHERITED CHC POP.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...ONGOING STRONG WARM ADVECTION AS THE PERIOD
BEGINS WILL PUSH TEMPERATURES INTO THE 70S ACROSS MUCH OF THE AREA
WED DESPITE ABUNDANT CLOUD COVER. INSTABILITY AND DEEP MOISTURE
WITHIN THE WARM SECTOR WILL MAINTAIN ELEVATED PRECIP CHANCES THROUGH
THE AFTERNOON HOURS. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS THE
AREA DURING WED BUT A MORE SIGNIFICANT LINE SEEM LIKELY JUST AHEAD
OF A STRONG COLD FRONT CROSSING THE AREA WED AFTERNOON. FORECAST
SOUNDINGS SHOW SOME LOW LEVEL JETTING BUT IT IS ON THE WEAK SIDE. AS
IS USUALLY THE CASE IN THE CAROLINAS IN WINTER CAPE WILL BE LACKING.
RIGHT NOW THE EVENT APPEARS RATHER BENIGN AS FAR AS STRONGER STORMS
GO BUT THIS COULD CHANGE SO WILL CONTINUE TO MONITOR IT.
IMPRESSIVE PERIOD OF COLD ADVECTION BEGINS WED NIGHT BEHIND THE
EXITING FRONT AND CONTINUES INTO THU AFTERNOON BEFORE WEAKENING.
TEMPS WILL DROP NEAR TO SLIGHTLY BELOW CLIMO FOR THE REMAINDER OF
THE PERIOD. HIGH PRESSURE SHIFTS EAST ACROSS THE OH VALLEY INTO THE
MID ATLANTIC REGION...SETTING THE STAGE FOR ANOTHER WEDGE EVENT LATE
IN THE WEEK. AT THE SAME TIME THE NEXT SOUTHERN STREAM SYSTEM EJECTS
FROM THE SOUTHWEST...DEVELOPING LOW PRESSURE OVER THE NORTHERN GULF
OF MEXICO AND TIGHTENING UP THE WEDGE OVER THE EAST COAST.
ISENTROPIC LIFT DEVELOPS AS EARLY AS FRI AND STRENGTHENS SAT. GIVEN
THE PRESENCE OF DEEP MOISTURE WITH THE LIFT WILL INTRODUCE SLIGHT
CHC POP FRI AND INCREASE POP TO LOW CHC FOR SAT.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 12Z...CURRENT TRENDS ARE HOLDING...WITH NOT MUCH CHANGE TO THE
PRESENT SET OF TAFS. LOOK FOR IFR/LIFR CONDITIONS TO CONTINUE FOR
MUCH OF THE DAY. THERE WILL BE SOME EROSION IN THE CLOUDS DUE TO
SOLAR INSOLATION. THE NAM BELIEVES THERE WILL BE SOME HOLES IN THE
CEILING BY AFTERNOON...HOWEVER THE GFS KEEPS US SOCKED IN THE ENTIRE
DAY. THINK WE WILL SEE SOME BROKEN SKIES THIS AFTERNOON...STILL A
MVFR CEILING. RISING DEWPOINTS AND SOUTHERLY FLOW WILL HELP FEED THE
LOW LEVEL MOISTURE. TONIGHT...ANY MVFR CONDITIONS LEFTOVER WILL
QUICKLY DETERIORATE TO IFR...WITH PERHAPS A BRIEF SHOWER ALONG THE
COAST.
EXTENDED OUTLOOK...SHOWERS LIKELY WITH MVFR/IFR ON MONDAY. IFR CIGS
EXPECTED ON TUESDAY. CHANCE OF SHOWERS AND MVFR/IFR CONDITIONS ON
WEDNESDAY WITH A COLD FRONT. VFR ON THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM SUNDAY...LATEST VISIBLE SAT IMAGERY DOES SHOW SOME
FEATURES THAT COULD RESEMBLE SEA FOG OR LOW STRATUS ACROSS THE
LOCAL WATERS. BUT FOR MOST PART...IT HAS NOT MATERIALIZED INTO A
COVERAGE THAT IS WIDESPREAD ENOUGH TO CONTINUE THE CURRENT DENSE
SEA FOG ADV. AS A RESULT...HAVE CANCELLED THE DENSE SEA FOG ADV.
WILL RE-LOOK AT ITS POSSIBILITY FOR LATER THIS EVENING AND
OVERNIGHT.
THE SFC PRESSURE PATTERN AND RELATIVELY LOOSE GRADIENT TO YIELD
MAINLY A SSW-SW FLOW AT 5 TO 10 KT FOR THIS AFTERNOON/EVENING.
FOR TONIGHT...WEAK SFC LOW ALONG THE APPROACHING COLD FRONT FROM
THE NW WILL TIGHTEN THE SFC PG ENOUGH FOR WINDS TO SLIGHTLY
INCREASE TO A RANGE OF 5 TO 15 KT. SIGNIFICANT SEAS OF 3 FT THIS
AFTERNOON...AND 3 TO 4 FT TONIGHT...WITH THE 4 FOOTERS MAINLY
ACROSS THE OUTER WATERS OFF CAPE FEAR. THE 2 TO 3 FOOT ESE-SE
GROUND SWELL AT 10-12 SECOND PERIODS...WILL DOMINATE THE SIG.
SEAS SPECTRUM. VERY LITTLE INPUT WILL COME FROM LOCALLY PRODUCED
WIND DRIVEN WAVES UNTIL TONIGHT.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...SOUTHWEST FLOW AROUND 15 KT MON WILL BECOME
NORTHWEST MON EVENING AS COLD FRONT MOVES ACROSS THE WATERS. THIS
FRONT WILL HAVE SOME COLD ADVECTION WITH IT BUT STRENGTH IS LIMITED
AND INITIALLY SPEEDS WILL BE IN THE 10 TO 15 KT RANGE. GRADIENT
STARTS TO BECOME MORE DEFINED TUE MORNING AS SURFACE HIGH TO THE
NORTH BUILDS DOWN THE EAST COAST. GRADIENT BECOMES MORE DEFINED TUE
AS COASTAL TROUGH SHARPENS AND SURFACE LOW MOVES ACROSS THE LOWER MS
VALLEY. AS A RESULT NORTHEAST FLOW WILL REMAIN A SOLID 15 KT THROUGH
THE END OF THE PERIOD. SEAS WILL RUN 3 TO 5 FT THROUGH THE PERIOD
WITH THE LARGEST CONCENTRATION OF 5 FT SEAS EXPECTED TUE NIGHT.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...STRONG SOUTHWEST FLOW AHEAD OF ADVANCING COLD
FRONT WILL APPROACH 25 KT AT TIMES ON WED. COLD FRONT MOVES ACROSS
THE WATERS WED EVENING WITH STRONG OFFSHORE FLOW DEVELOPING IN ITS
WAKE. COMBINATION OF PINCHED GRADIENT AND COLD ADVECTION WILL KEEP
SPEEDS AROUND 20 KT INTO THU AFTERNOON. SLIGHT REDUCTION IN GRADIENT
AND WANING COLD ADVECTION WILL DROP NORTHEAST FLOW TO A SOLID 15 KT
FOR THE REMAINDER OF THE PERIOD. SEAS BUILD TO 4 TO 6 FT WED AHEAD
OF THE COLD FRONT. SCA SEAS LINGER INTO WED NIGHT BEFORE OFFSHORE
FLOW IS ABLE TO KNOCK SEAS BACK TO 3 TO 5 FT FOR THU AND THU NIGHT.
&&
.TIDES/COASTAL FLOODING...
AS OF 3 AM SUNDAY...WE ARE NOW TWO DAYS PAST THE NEW MOON BUT
UNUSUALLY LOW WATER LEVELS WILL CONTINUE AT LOW TIDE TODAY.
ASTRONOMICAL LOW TIDE WILL OCCUR AROUND 3:15 THIS AFTERNOON AND THE
ETSURGE/ESTOFS CONSENSUS IS FOR WATER LEVELS SOUTH OF CAPE FEAR TO
REACH -1.30 FEET MLLW...WITH LESSER DEPARTURES NORTH OF CAPE FEAR.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH/TRA
SHORT TERM...III
LONG TERM...III
AVIATION...DL
TIDES/COASTAL FLOODING...TRA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
328 PM CST SUN FEB 2 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 328 PM CST SUN FEB 2 2014
MAIN CHALLENGE THROUGH THE PERIOD WILL BE TEMPERATURES AND CLOUD
COVER. GFS/NAM/ECMWF/GEM SYNOPTIC PATTERN IN GOOD AGREEMENT AND
WILL USE A BLENDED SOLUTION FOR THIS FORECAST PACKAGE.
21 UTC SURFACE ANALYSIS SHOWS A SURFACE TROUGH AXIS FROM DEVILS
LAKE TO BISMARCK WITH A COLD FRONT DRAPED FROM WILLISTON TO
DICKINSON. OVERCAST SKIES UPSTREAM FROM THE FRONT ACROSS NORTHEAST
MT INTO SASKATCHEWAN NOT WELL RESOLVED IN GLOBAL MODELS...BOTH
SHOWING CLOUDS BREAKING UP AS THEY MOVE EAST. SATELLITE IMAGERY
SHOWS FEW BREAKS AND WITH SURFACE RIDGE AXIS ESTABLISHING ITSELF
ACROSS THE FORECAST AREA OVERNIGHT...SEE NO REASON CLOUDS WILL
COMPLETELY DISSIPATE. WILL FOLLOW RAP 925 HPA RH OUTPUT WHICH
MOVES LOW CLOUDS ACROSS THE REGION THIS EVENING AND OVERNIGHT FOR
AT LEAST PARTLY CLOUDY SKIES. AS A RESULT...INCREASED CLOUD COVER
AND LOW TEMPERATURES TONIGHT DESPITE LOW-LEVEL COLD AIR ADVECTION
BEHIND THE FRONT. EXACT TEMPERATURES WILL DEPEND ON CLOUD COVER...
BUT STILL THINK MOST AREAS SHOULD DROP BELOW ZERO. NO NEED FOR
WIND CHILL HEADLINES TONIGHT WITH LIGHT WIND AROUND 5 TO 10 MPH.
MONDAY WILL SEE A MIX OF CLOUDS AND SUN WITH TEMPERATURES 5 TO 10
DEGREES COOLER THAN TODAY. LIGHT WEST-NORTHWEST FLOW WILL SHIFT TO
A MORE NORTHERLY DIRECTION AS 1040 HPA PLUS SURFACE HIGH TAKES UP
RESIDENCE ACROSS THE NORTHERN ROCKIES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 328 PM CST SUN FEB 2 2014
STORM TRACK TUESDAY/WEDNESDAY WILL REMAIN WELL SOUTH OF THE
FORECAST AREA WITH DRY NORTHERLY FLOW ACROSS THE NORTHERN PLAINS.
TEMPERATURES...HOWEVER...WILL CONTINUE TO BE 10 TO 20 DEGREES
BELOW EARLY FEBRUARY NORMALS UNDER PERSISTENT COLD AIR ADVECTION
REGIME. AFTERNOON HIGHS BOTH DAYS LIKELY TO BE WITHIN A FEW
DEGREES PLUS OR MINUS THE ZERO MARK WITH NIGHTTIME LOWS DIPPING
WELL INTO THE MID TEENS BELOW ZERO AND POSSIBLY COLDER ONCE AGAIN
INCREASING THE SEEMINGLY ENDLESS WIND CHILL THREAT.
WEDNESDAY NIGHT THROUGH SUNDAY...LITTLE CHANGE EXPECTED THROUGH THE
REMAINDER OF THE WORK WEEK. WEDGE OF SURFACE HIGH PRESSURE WILL
KEEP REGION DRY ALONG WITH TEMPERATURES CONTINUING WELL BLO AVERAGE.
MODELS DIVERGE NEXT WEEKEND ON SOLUTIONS BUT OVERALL LOOKS LIKE
STORM TRACK WILL REMAIN TO OUR SOUTH WITH FA REMAINING DRY BUT BLO
AVERAGE TEMPERATURES PERSISTING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 102 PM CST SUN FEB 2 2014
PATCH OF VFR/ISOLD MVFR CIGS WILL TRACK EAST OF THE VALLEY ACROSS
NW/N CENTRAL MN THIS AFTERNOON. CLEAR AREA IN BETWEEN ANOTHER AREA
OF MVFR/VFR CIGS ENTERING NW CORNER OF ND AND IF IT HOLDS TOGETHER
WILL REACH FAR NW FA LATE THIS AFTERNOON SPREADING EAST THIS
EVENING. EXPECT A WSHFT LATE THIS AFTERNOON FROM SW TO NW.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
102 PM CST SUN FEB 2 2014
.UPDATE...
ISSUED AT 102 PM CST SUN FEB 2 2014
MADE SOME MINOR ADJUSTMENTS TO SKY GRIDS AS STRATUS HAS MOVED INTO
NORTHWEST MN WITH SOME DEGREE OF CLEARING WEST OF THE RED RIVER.
ALSO RAISED MAXIMUM TEMPERATURES A DEGREE OR TWO TO BLEND WITH
LATEST OBSERVATIONS. REST OF THE FORECAST STILL ON TRACK.
UPDATE ISSUED AT 1018 AM CST SUN FEB 2 2014
STILL A FEW OBSERVATION SITES ACROSS ROSEAU/LAKE OF THE WOODS
COUNTIES WITH WIND CHILL VALUES AROUND 25 BELOW...BUT WITH AIR
TEMPERATURES RISING AND RELATIVELY LIGHT WIND SPEEDS THROUGH THE
DAY...LET WIND CHILL ADVISORY EXPIRE AT 10 AM CST.
STRATUS FROM THE RED RIVER VALLEY INTO PORTIONS OF NORTHWEST AND
WEST CENTRAL MN WILL CONTINUE TO MOVE EASTWARD PER RAP 925 HPA RH
OUTPUT. DO EXPECT PEAKS OF SUNSHINE TO INCREASE FROM WEST TO EAST
THROUGH THE DAY AND ALTHOUGH CLOUDS MAY INITIALLY LIMIT
TEMPERATURE RISES...MAXIMUM VALUES SHOULD STILL REACH THE UPPER
SINGLE DIGITS TO MID TEENS ABOVE ZERO THIS AFTERNOON.
DID ADJUST SKY COVER TO SLOW EASTWARD PROGRESSION OF CLOUD
COVER...BUT REST OF FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES
NEEDED AT THIS TIME.
UPDATE ISSUED AT 635 AM CST SUN FEB 2 2014
MAIN CHANGE WAS TO PULL MORE COUNTIES OUT OF THE WIND CHILL
ADVISORY. THE STRATUS CONTINUES TO SPREAD EASTWARD ACROSS THE CWA
AND ONLY THE FAR NORTHERN AND EASTERN COUNTIES CURRENTLY REACHING
WIND CHILL CRITERIA. WITH WARM AIR ADVECTION MOVING IN TEMPS WILL
CONTINUE TO BE STEADY OR SLOWLY RISING. ADJUSTED CLOUD COVER FOR
CURRENT SAT TRENDS AND PUT IN AN ISOLATED FLURRY MENTION AS
SEVERAL SITES HAVE REPORTED -SN.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 313 AM CST SUN FEB 2 2014
TEMPS CONTINUE TO BE THE MAIN FORECAST CONCERN FOR THE SHORT TERM.
SAT LOOP SHOWS A FAIR AMOUNT OF STRATUS OVER THE SOUTHERN AND
WESTERN COUNTIES...MOVING SLOWLY EASTWARD. THE CLOUDS AND SOME
WEAK WARM AIR ADVECTION HAVE KEPT THE TEMPS WARMER THAN EXPECTED.
WHILE THE EASTERN COUNTIES ARE IN THE TEENS BELOW ZERO THE WEST
HAS STAYED IN THE SINGLE DIGITS ABOVE. WINDS WILL PICK UP A BIT
LATER THIS MORNING...SO THINK THAT MOST LOCATIONS WILL SEE WIND
CHILLS DROP BELOW CRITERIA LATER THIS MORNING. HOWEVER...THE
SOUTHWESTERN COUNTIES ARE MOST LIKELY TO STAY CLOUDY AND ABOVE
ZERO...WITH WIND CHILLS STAYING ABOVE -20 F. WILL TRIM THOSE
COUNTIES OUT OF THE ADVISORY AND MAY HAVE TO MAKE SOME MORE
ADJUSTMENTS AT THE NEXT UPDATE.
TEMPS SHOULD WARM TO ABOVE ZERO DURING THE DAY TODAY WITH WEAK
WARM AIR ADVECTION ON THE FRONT SIDE OF A SFC TROUGH AXIS. THE
MILD WARM UP WILL BE SHORT LIVED AS THE SHORTWAVE OVER CANADA
MOVES OFF INTO ONTARIO. THERE SHOULD BE SOME WEAK COLD AIR
ADVECTION BEHIND THE SFC TROUGH AND LOWS TONIGHT SHOULD BE WELL
BELOW ZERO. THERE SHOULD BE PLENTY OF SUN ON MONDAY BUT NEUTRAL TO
WEAK COLD ADVECTION WILL CONTINUE TO KEEP TEMPS MAINLY IN THE
SINGLE DIGITS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 AM CST SUN FEB 2 2014
THE EARLY PART OF THE WORK WEEK WILL CONTINUE TO SEE COLDER THAN
NORMAL TEMPERATURES AS A POSITIVELY TILTED TROUGH DIGS INTO THE
WESTERN CONUS. A STRONG ARCTIC HIGH OF MORE THAN 1040MB SETTLES
OVER THE NORTHERN ROCKIES AND SPREADS ITS INFLUENCE INTO THE
NORTHERN PLAINS. MONDAY AND TUESDAY NIGHT WILL CONTINUE TO BE VERY
COLD IN THE TEENS BELOW ZERO AND HIGHS ON TUESDAY WILL NOT REALLY
GET INTO THE POSITIVE NUMBERS.
.WEDNESDAY-SATURDAY...ARCTIC HIGH PRESSURE WILL CONTINUE TO SPREAD
FROM THE NORTHERN ROCKIES INTO THE PLAINS THROUGH THE END OF THE
WORK WEEK. DRY LOW-LEVEL FLOW FROM THE NORTH AND NORTHWEST WILL KEEP
TEMPS BELOW NORMAL THROUGH THE PERIOD. HOWEVER...925 MB TEMPS FROM
-20 TO -25C ON WEDNESDAY WILL GRADUALLY MODERATE BY A FEW DEGREES
EACH DAY INTO THE WEEKEND AS WINDS BECOME MORE ZONAL...SO A SLOW UPWARD
TREND IN TEMPS IS EXPECTED. WIND CHILLS WILL BE A CONCERN WEDNESDAY
INTO THURSDAY THOUGH WITH HIGHS ON WEDNESDAY REMAINING MAINLY BELOW
ZERO...AND NOT MUCH ABOVE ZERO ON THURSDAY.
MODEL SOLUTIONS DO DIVERGE MORE BY LATE WEEK. AN UPPER LOW IS
EXPECTED TO EJECT FROM THE WEST INTO THE SOUTHERN/CENTRAL
PLAINS...BUT CONFIDENCE IN HOW THE WEAKER NORTHERN BRANCH OF THE JET
WILL INTERACT WITH THE SOUTHERN STREAM IS LOW. THE 00Z ECMWF WOULD
SUGGEST DRY CONDITIONS PERSISTING THROUGH THE WEEKEND UNDER HIGH
PRESSURE...WHILE THE GFS SHOWS A FEW LIGHT SNOW CHANCES FOR LATE
WEEK. DID KEEP SOME LOW POPS GOING FOR SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 102 PM CST SUN FEB 2 2014
PATCH OF VFR/ISOLD MVFR CIGS WILL TRACK EAST OF THE VALLEY ACROSS
NW/N CENTRAL MN THIS AFTERNOON. CLEAR AREA IN BETWEEN ANOTHER AREA
OF MVFR/VFR CIGS ENTERING NW CORNER OF ND AND IF IT HOLDS TOGETHER
WILL REACH FAR NW FA LATE THIS AFTERNOON SPREADING EAST THIS
EVENING. EXPECT A WSHFT LATE THIS AFTERNOON FROM SW TO NW.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...ROGERS
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...VOELKER
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1018 AM CST SUN FEB 2 2014
.UPDATE...
ISSUED AT 1018 AM CST SUN FEB 2 2014
STILL A FEW OBSERVATION SITES ACROSS ROSEAU/LAKE OF THE WOODS
COUNTIES WITH WIND CHILL VALUES AROUND 25 BELOW...BUT WITH AIR
TEMPERATURES RISING AND RELATIVELY LIGHT WIND SPEEDS THROUGH THE
DAY...LET WIND CHILL ADVISORY EXPIRE AT 10 AM CST.
STRATUS FROM THE RED RIVER VALLEY INTO PORTIONS OF NORTHWEST AND
WEST CENTRAL MN WILL CONTINUE TO MOVE EASTWARD PER RAP 925 HPA RH
OUTPUT. DO EXPECT PEAKS OF SUNSHINE TO INCREASE FROM WEST TO EAST
THROUGH THE DAY AND ALTHOUGH CLOUDS MAY INITIALLY LIMIT
TEMPERATURE RISES...MAXIMUM VALUES SHOULD STILL REACH THE UPPER
SINGLE DIGITS TO MID TEENS ABOVE ZERO THIS AFTERNOON.
DID ADJUST SKY COVER TO SLOW EASTWARD PROGRESSION OF CLOUD
COVER...BUT REST OF FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES
NEEDED AT THIS TIME.
UPDATE ISSUED AT 635 AM CST SUN FEB 2 2014
MAIN CHANGE WAS TO PULL MORE COUNTIES OUT OF THE WIND CHILL
ADVISORY. THE STRATUS CONTINUES TO SPREAD EASTWARD ACROSS THE CWA
AND ONLY THE FAR NORTHERN AND EASTERN COUNTIES CURRENTLY REACHING
WIND CHILL CRITERIA. WITH WARM AIR ADVECTION MOVING IN TEMPS WILL
CONTINUE TO BE STEADY OR SLOWLY RISING. ADJUSTED CLOUD COVER FOR
CURRENT SAT TRENDS AND PUT IN AN ISOLATED FLURRY MENTION AS
SEVERAL SITES HAVE REPORTED -SN.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 313 AM CST SUN FEB 2 2014
TEMPS CONTINUE TO BE THE MAIN FORECAST CONCERN FOR THE SHORT TERM.
SAT LOOP SHOWS A FAIR AMOUNT OF STRATUS OVER THE SOUTHERN AND
WESTERN COUNTIES...MOVING SLOWLY EASTWARD. THE CLOUDS AND SOME
WEAK WARM AIR ADVECTION HAVE KEPT THE TEMPS WARMER THAN EXPECTED.
WHILE THE EASTERN COUNTIES ARE IN THE TEENS BELOW ZERO THE WEST
HAS STAYED IN THE SINGLE DIGITS ABOVE. WINDS WILL PICK UP A BIT
LATER THIS MORNING...SO THINK THAT MOST LOCATIONS WILL SEE WIND
CHILLS DROP BELOW CRITERIA LATER THIS MORNING. HOWEVER...THE
SOUTHWESTERN COUNTIES ARE MOST LIKELY TO STAY CLOUDY AND ABOVE
ZERO...WITH WIND CHILLS STAYING ABOVE -20 F. WILL TRIM THOSE
COUNTIES OUT OF THE ADVISORY AND MAY HAVE TO MAKE SOME MORE
ADJUSTMENTS AT THE NEXT UPDATE.
TEMPS SHOULD WARM TO ABOVE ZERO DURING THE DAY TODAY WITH WEAK
WARM AIR ADVECTION ON THE FRONT SIDE OF A SFC TROUGH AXIS. THE
MILD WARM UP WILL BE SHORT LIVED AS THE SHORTWAVE OVER CANADA
MOVES OFF INTO ONTARIO. THERE SHOULD BE SOME WEAK COLD AIR
ADVECTION BEHIND THE SFC TROUGH AND LOWS TONIGHT SHOULD BE WELL
BELOW ZERO. THERE SHOULD BE PLENTY OF SUN ON MONDAY BUT NEUTRAL TO
WEAK COLD ADVECTION WILL CONTINUE TO KEEP TEMPS MAINLY IN THE
SINGLE DIGITS.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 AM CST SUN FEB 2 2014
THE EARLY PART OF THE WORK WEEK WILL CONTINUE TO SEE COLDER THAN
NORMAL TEMPERATURES AS A POSITIVELY TILTED TROUGH DIGS INTO THE
WESTERN CONUS. A STRONG ARCTIC HIGH OF MORE THAN 1040MB SETTLES
OVER THE NORTHERN ROCKIES AND SPREADS ITS INFLUENCE INTO THE
NORTHERN PLAINS. MONDAY AND TUESDAY NIGHT WILL CONTINUE TO BE VERY
COLD IN THE TEENS BELOW ZERO AND HIGHS ON TUESDAY WILL NOT REALLY
GET INTO THE POSITIVE NUMBERS.
.WEDNESDAY-SATURDAY...ARCTIC HIGH PRESSURE WILL CONTINUE TO SPREAD
FROM THE NORTHERN ROCKIES INTO THE PLAINS THROUGH THE END OF THE
WORK WEEK. DRY LOW-LEVEL FLOW FROM THE NORTH AND NORTHWEST WILL KEEP
TEMPS BELOW NORMAL THROUGH THE PERIOD. HOWEVER...925 MB TEMPS FROM
-20 TO -25C ON WEDNESDAY WILL GRADUALLY MODERATE BY A FEW DEGREES
EACH DAY INTO THE WEEKEND AS WINDS BECOME MORE ZONAL...SO A SLOW UPWARD
TREND IN TEMPS IS EXPECTED. WIND CHILLS WILL BE A CONCERN WEDNESDAY
INTO THURSDAY THOUGH WITH HIGHS ON WEDNESDAY REMAINING MAINLY BELOW
ZERO...AND NOT MUCH ABOVE ZERO ON THURSDAY.
MODEL SOLUTIONS DO DIVERGE MORE BY LATE WEEK. AN UPPER LOW IS
EXPECTED TO EJECT FROM THE WEST INTO THE SOUTHERN/CENTRAL
PLAINS...BUT CONFIDENCE IN HOW THE WEAKER NORTHERN BRANCH OF THE JET
WILL INTERACT WITH THE SOUTHERN STREAM IS LOW. THE 00Z ECMWF WOULD
SUGGEST DRY CONDITIONS PERSISTING THROUGH THE WEEKEND UNDER HIGH
PRESSURE...WHILE THE GFS SHOWS A FEW LIGHT SNOW CHANCES FOR LATE
WEEK. DID KEEP SOME LOW POPS GOING FOR SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 635 AM CST SUN FEB 2 2014
STRATUS CONTINUES TO COVER MOST OF THE CWA WITH KTVF BRIEFLY
CLEAR. THE STRATUS HAS SEEMED TO STRADDLE THE LINE BETWEEN VFR AND
MVFR. THE BACK EDGE OF THE STRATUS JUST STARTING TO MOVE INTO THE
WESTERN FORECAST AREA SO THINK THAT ALL SITES WILL BE VFR BY MID
TO LATE MORNING. VFR CONDITIONS WILL CONTINUE THROUGH THE REST OF
THE PERIOD WITH SOUTHWEST WINDS BECOMING MORE WESTERLY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...ROGERS
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...JR
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1155 AM CST SUN FEB 2 2014
.AVIATION...
/18Z TAFS/
WIDESPREAD MVFR CONDITIONS PREVAIL ACROSS THE METROPLEX AT THIS
TIME BUT PRECIPITATION INTENSITY IS EXPECTED TO INCREASE OVER THE
NEXT FEW HOURS. AN IMPRESSIVE BAND OF MODERATE TO HEAVY SLEET HAS
DEVELOPED WEST OF THE MAJOR AIRPORTS AND THIS IS LIKELY TO REMAIN
JUST TO THE WEST. THE BATTLE BETWEEN WARMING TEMPERATURES ALOFT
AND COLD SURFACE TEMPERATURES CONTINUES TO FAVOR MAINLY A
RAIN/FREEZING RAIN PRECIP TYPE IN THE METROPLEX THROUGH AFTERNOON.
ALTHOUGH AS THE SHORTWAVE GETS CLOSER...TEMPS ALOFT ARE LIKELY TO
COOL. WILL KEEP A MENTION OF SOME SLEET IN FOR A FEW HOURS THIS
AFTERNOON BUT THINK MAINLY FREEZING RAIN WILL PREVAIL. LITTLE ICE
ACCUMULATION IS EXPECTED AS GROUND/SURFACE TEMPERATURES APPEAR TOO
WARM. SOME LIGHT ICING IS EXPECTED ON EXPOSED SURFACES.
OTHERWISE...PRECIPITATION COMES TO AN END THIS EVENING AND MVFR
CIGS WILL PERSIST.
AT WACO...MAINLY LIGHT RAIN WILL PREVAIL THROUGH THE AFTERNOON
WITH MVFR CIGS THROUGH TONIGHT.
DUNN
&&
.UPDATE...
AS OF 11 AM...THE FREEZING LINE EXTENDED FROM SHERMAN THROUGH
FORT WORTH ALLIANCE TO STEPHENVILLE AND COMANCHE. RADAR AND
SURFACE REPORTS SHOW A DECENT BAND OF SLEET FROM CISCO THROUGH
POSSUM KINGDOM TO NORTHWESTERN COOKE COUNTY INTO OKLAHOMA. WE
DID AN UPDATE EARLIER TO ADD JACK AND PALO PINTO COUNTIES TO THE
WINTER STORM WARNING. GIVEN THE DEW POINT DEPRESSIONS AND THE
ACTUAL TEMPERATURES TO THE IMMEDIATE NORTH...AM NOT EXPECTING A
DRAMATIC DROP IN TEMPERATURES THIS AFTERNOON. THE HEAVIEST WINTRY
PRECIPITATION SHOULD REMAIN TO THE NORTHWEST TO THE METROPLEX AS
PER THE PREVIOUS FORECAST. THE MAIN CHANGES ARE TO LOWER
TEMPERATURES SOUTH OF I-20 AND TO ADJUST THE HOURLY GRIDS.
UPDATES HAVE BEEN SENT.
58
&&
.PREV DISCUSSION... /ISSUED 442 AM CST SUN FEB 2 2014/
EARLY MORNING WATER VAPOR SATELLITE IMAGERY SHOWED A STRONG
SHORTWAVE TROUGH OVER THE AZ/NM/MEXICO BORDER...MOVING EAST
TOWARDS TEXAS. LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS
TROUGH WAS EVIDENT OVER FAR WEST TEXAS AND THE TX PANHANDLE WHERE
A PLUME OF DEEP WATER VAPOR WAS OBSERVED DEVELOPING OUT AHEAD OF
THE TROUGH. A 00Z UPPER AIR ANALYSIS REVEALED 500 MB TEMPERATURES
OF -18 TO -20 DEG C JUST OUT AHEAD OF THE TROUGH. THIS COLD AIR
ALOFT HAD LIKELY ADVECTED OVER LOCATIONS FROM MIDLAND TO
LUBBOCK...LOWERING STABILITY ALOFT. THIS AREA CORRESPONDED WELL
WITH OBSERVED LIGHTNING STRIKES IN CELLULAR CONVECTION OBSERVED ON
REGIONAL RADARS EXTENDING FROM MIDLAND NORTHEAST TO CHILDRESS AT
0930Z. 00Z UPPER AIR ANALYSIS SHOWED THE 850 MB FREEZING LINE
HOLDING UP IN THE TX PANHANDLE...WITH A WARM MOIST AIR MASS ALOFT
OVER NORTH TEXAS AT 10 DEG C. THIS LINE HAD OBVIOUSLY SHIFTED
SOUTH IN THE 10 HRS SINCE THE WEATHER BALLOON OBSERVATIONS AS
LIGHT SNOW WAS OBSERVED AS FAR SOUTH AS SYNDER TX AT 0930Z.
FIRST...A SUMMARY OF CHANGES TO THE PREVIOUS FORECAST:
WENT AHEAD AND EXPANDED THE WINTER WEATHER ADVISORY SOUTH TO
INCLUDE MILLS...HAMILTON...BOSQUE...HILL...ELLIS...AND KAUFMAN
COUNTIES. THIS WAS DONE PRIMARILY DUE TO AN INCREASED THREAT OF
FREEZING RAIN AND LIGHT ICE ACCUMULATIONS ON ELEVATED ROAD
SURFACES THIS AFTERNOON.
EXPECT THAT ALL WINTRY PRECIPITATION WILL REMAIN ALONG AND
NORTHWEST OF A LINE FROM GOLDTHWAITE TO HILLSBORO TO COOPER. THIS
IS AS FAR SOUTHEAST AS WE HAVE THE FREEZING LINE CREEPING THIS
AFTERNOON WHILE PRECIPITATION IS STILL ACTIVE OVER THE REGION.
TEMPERATURES WILL LIKELY FALL BELOW FREEZING ACROSS ALL OF NORTH
AND CENTRAL TEXAS TONIGHT...BUT PRECIPITATION IS EXPECTED TO END
ABRUPTLY LATE THIS AFTERNOON FROM SOUTHWEST TO NORTHEAST AS A DRY
SLOT KICKS OUT OVER THE REGION ALOFT.
BEFORE THE DRY AIR ALOFT ARRIVES HOWEVER...CONFIDENCE REMAINS HIGH
THAT WE WILL SEE ENOUGH WINTRY PRECIPITATION WHERE WE ALREADY HAD
WINTRY WEATHER ADVISORIES OR A WINTER STORM WARNING IN EFFECT.
FOR LOCATIONS THAT WERE ALREADY INCLUDED IN WINTER WEATHER
ADVISORIES OR WARNINGS...THERE WERE ONLY MINOR CHANGES MADE TO
THE PREVIOUS FORECAST. THE BIGGEST CHANGE OF NOTE WAS AN INCREASE
IN THE AMOUNTS OF FREEZING RAIN/ICE ACCUMULATION FROM A FEW
HUNDREDTHS OF AN INCH TO JUST OVER A TENTH OF AN INCH IN A NARROW
BAND JUST NORTHWEST OF THE SURFACE FREEZE LINE THIS AFTERNOON.
THIS NARROW BAND OF ENHANCED ICE ACCUMULATION EXTENDS FROM
COMANCHE TO DFW TO BONHAM. THE REASONS FOR THIS WILL BE DISCUSSED
BELOW...BUT ICE ACCUMULATIONS ARE PRIMARILY EXPECTED TO REMAIN
TIED TO ELEVATED SURFACES TODAY. MOST OF THE FREEZING RAIN IS
EXPECTED TO FALL WITH TEMPERATURES IN THE 30-32 DEGREE F
RANGE...MEANING THAT MOST OF THE RAIN WILL NOT BE COLD ENOUGH TO
FREEZE ON CONTACT WITH THE RELATIVELY WARM GROUND/SOIL
TEMPERATURES WE HAVE IN PLACE ACROSS THE REGION. THIS DOES NOT
APPLY TO BRIDGES AND OVERPASSES OF COURSE AS THESE SURFACES WILL
COOL BELOW FREEZING SOON AFTER THE AIR TEMPERATURE DROPS BELOW
FREEZING TODAY.
THE FORECAST FOR SNOWFALL AMOUNTS AND LOCATIONS REMAINS LARGELY
UNCHANGED. LOCATIONS ALONG AND NORTHWEST OF A BRECKENRIDGE TO
SHERMAN LINE STILL LOOK TO BE THE MOST FAVORABLE LOCATIONS FOR 2-4
INCHES OF SNOW ACCUMULATION WITH SOME SLEET AND FREEZING RAIN
MIXED IN. A WINTER STORM WARNING REMAINS IN EFFECT FOR THESE
LOCATIONS AS A RESULT. IN BETWEEN THE DFW AREA...WHICH IS EXPECTED
TO SEE MOSTLY FREEZING RAIN AND A LATE TRANSITION TO SLEET/SNOW...
AND THE WINTER STORM WARNING...THERE REMAINS A GREAT DEAL OF
UNCERTAINTY REGARDING THE EXACT AMOUNTS OF SNOW/SLEET/FREEZING
RAIN AS THIS REPRESENTS THE LIKELY TRANSITION ZONE BETWEEN ALL 3
PRECIPITATION TYPES THROUGHOUT THE DAY TODAY. LEFT THESE AREAS IN
AN ADVISORY FOR NOW AS CONFIDENCE IN RECEIVING AMOUNTS LARGE
ENOUGH OF ANY INDIVIDUAL TYPE OF PRECIPITATION REMAINS LOW AT THIS
TIME. SUFFICE TO SAY TRAVEL WILL STILL BE A PROBLEM FOR THESE
LOCATIONS AS A MIXED BAG OF WINTRY WEATHER WILL LEAD TO SLICK
ROADWAYS...ESPECIALLY ON BRIDGES AND OVERPASSES.
SECOND...METEOROLOGICAL DISCUSSION REGARDING OUR WINTER WEATHER
EVENT:
THE SHORTWAVE TROUGH IS EXPECTED TO SWING NORTHEAST OVER THE
REGION TODAY...SPREADING LARGE SCALE FORCING FOR ASCENT OVER THE
ENTIRE CWA THIS MORNING. AS MENTIONED AT THE BEGINNING OF THE
DISCUSSION...DIFFERENTIAL ADVECTION WILL LIKELY LEAD TO A
REDUCTION IN STABILITY ALOFT FROM WEST TO EAST THROUGHOUT THE DAY
TODAY AS WELL. THIS POINT IN PARTICULAR GREATLY COMPLICATES THE
FORECAST BECAUSE PRECIPITATION AMOUNTS BECOME MUCH MORE RESPONSIVE
TO MESOSCALE FORCING AS OPPOSED TO SYNOPTIC SCALE CONSIDERATIONS.
THIS WILL RESULT IN CELLULAR CONVECTION MIXED IN BROADER
PRECIPITATION ZONES RESULTING IN LOCALLY ENHANCED PRECIPITATION
AMOUNTS FROM WHAT IS REFLECTED IN MODEL GUIDANCE AND OUR OFFICIAL
FORECAST. IN GENERAL...WE EXPECT LOW-LEVEL TEMPERATURES TO FALL
THROUGHOUT THE DAY TODAY FROM NORTHWEST TO SOUTHEAST. WARM AIR
ADVECTION WORKING AGAINST THE SOUTHWARD MOVING CANADIAN AIRMASS IS
WHAT IS DRIVING ALL OF THE DIFFERENT PRECIPITATION TYPES ACROSS
NORTH TEXAS TODAY.
MODEL FORECAST SOUNDINGS CONSISTENTLY SHOW THAT AIR PARCELS LIFTED
FROM AROUND THE 750 MB LEVEL HAVE POSITIVE CAPE ANYWHERE FROM 100
TO 250 J/KG WITH LITTLE TO NO CONVECTIVE INHIBITION PRESENT. THIS
UPRIGHT INSTABILITY WILL RESULT IN EMBEDDED THUNDERSTORMS ACROSS
THE REGION FROM THIS MORNING THROUGH EARLY THIS AFTERNOON...SO
WENT AHEAD WITH A MENTION OF ISOLATED THUNDER IN THE FORECAST AS
CONFIDENCE IS ACTUALLY PRETTY HIGH IN THIS PANNING OUT. THE MORE
IMPORTANT QUESTION IS: HOW WILL THIS AFFECT WINTER WEATHER IMPACTS
ACROSS NORTH TEXAS TODAY? THE ANSWER TO THAT QUESTION IS
TRICKY...HOWEVER IT SEEMS MOST LIKELY THAT EMBEDDED STORMS WILL
NOT CHANGE IMPACTS MUCH FROM WHAT WERE ARE CURRENTLY HIGHLIGHTING
IN OUR WINTER STORM WARNINGS AND WINTRY WEATHER ADVISORIES.
ANY EMBEDDED THUNDERSTORMS IN THE WINTER STORM WARNING AREA WILL
ONLY SERVE TO ENHANCE SNOWFALL AMOUNTS/ACCUMULATION. THESE ARE THE
LOCATIONS WE ALREADY FEEL WILL SUFFER FROM THE WORST ROAD
CONDITIONS...SO ADDITIONAL SNOWFALL WILL ONLY EXACERBATE
DETERIORATING ROAD CONDITIONS. WHILE THIS IS NOT GOOD NEWS...A
WINTER STORM WARNING IS STILL THE MOST APPROPRIATE WAY TO ADDRESS
THESE IMPACTS AND THAT WILL NOT CHANGE WITH ADDITIONAL SNOWFALL.
IF WE GET THUNDERSTORMS ALONG A COMANCHE TO DFW TO BONHAM
LINE...WHERE WE EXPECT A TENTH OF AN INCH OF FREEZING RAIN...THIS
WILL ONLY MAKE FREEZING RAIN FALL FASTER ACROSS THE AREA. WHILE
THIS SOUNDS REALLY BAD...ITS NOT OBVIOUS THAT THIS WILL RESULT IN
ADDITIONAL ICE ACCUMULATION. HEAVIER PRECIPITATION RATES WILL
LIKELY JUST CAUSE MORE OF THE PRECIPITATION TO RUN OFF AREA
ROADWAYS...AS LONG AS TEMPERATURES REMAIN IN THE 30 O 32 DEGREE F
RANGE. NOW THIS POINT IS EXTREMELY IMPORTANT...IF TEMPERATURES
WERE TO FALL INTO THE 20S WITH ENHANCED FREEZING RAIN RATES...WE
WOULD BE IN BIG TROUBLE AS ICE WOULD ACCUMULATE VERY RAPIDLY ON
AREA ROADWAYS. HOWEVER...AT THIS TIME NEARLY ALL AVAILABLE
GUIDANCE INDICATES THAT TEMPERATURES WILL REMAIN IN THIS 30 TO 32
DEGREE RANGE OVER THE DFW AREA WHILE MEASURABLE PRECIPITATION IS
FALLING. OBVIOUSLY...WE WILL HAVE TO WATCH THIS VERY CLOSELY
THROUGHOUT THE DAY TODAY.
ONCE AGAIN FOR THOSE COUNTIES IN BETWEEN DFW AND THE WINTER STORM
WARNING...THIS IS WHERE THUNDERSTORMS COULD RESULT IN THE GREATEST
DEVIATION FROM THE CURRENT FORECAST. EMBEDDED STORMS NOT ONLY
ENHANCE PRECIPITATION AMOUNTS/RATES...BUT THEY ALSO TEND TO COOL
THE ATMOSPHERE THROUGH THE DEPTH OF THEIR UPDRAFT. THIS MAY
ACTUALLY RESULT IN A COMPLETE CHANGE OVER IN PRECIPITATION TYPE
NEAR THE PRECIPITATION TYPE RESULTING IN A QUICK CHANGE OVER FROM
FREEZING RAIN TO MODERATE TO HEAVY SLEET. WE WILL WATCH FOR ANY
PERSISTENT AREAS OF THUNDERSTORMS THAT MAY LINE UP IN THIS
TRANSITION ZONE...AND MAY HAVE TO UPGRADE SOME OF THESE AREAS TO A
WINTER STORM WARNING IF IT LOOKS LIKE A CHANGE IN PRECIPITATION
TYPE WILL RESULT IN SIGNIFICANT ADDITIONAL ACCUMULATION OF SLEET
OR SNOW.
THIS BRINGS US TO THE LEAST CERTAIN PORTION OF THE FORECAST WHICH
IS THE VERTICAL THERMAL PROFILE. 00Z AND 06Z MODELS HAVE REALLY
BEEN STRUGGLING TO KEEP UP WITH AN ACCURATE DEPICTION OF THE
FREEZING LINE AT THE SURFACE. THE 00Z NAM WAS THE ONLY MODEL THAT
HAD A GOOD HANDLE ON THE 06Z FREEZING LINE AT THE SURFACE AS EVERY
OTHER MODEL THAT WAS LOOKED AT WAS ANYWHERE FROM 2-4 DEGREES TOO
WARM. THEREFORE...THIS FORECAST FOR PRECIPITATION TYPE AND SURFACE
TEMPERATURES IS HEAVILY WEIGHTED TOWARDS THE COOLER 00Z NAM.
NOTABLY...THE 06Z RAP KEPT SURFACE TEMPERATURES ABOVE FREEZING ALL
DAY ACROSS THE DFW AREA...SO THE EXACT FORECAST FOR PRECIPITATION
TYPE REMAINS AN UNCERTAIN ONE AS OF THIS MORNING.
MODELS /EVEN THE WARMEST ONES/ CONSISTENTLY SHOW THE VERTICAL
THERMAL PROFILE WILL BE COLD ENOUGH FOR MAINLY SLEET AND SNOW
WHERE WE CURRENTLY HAVE THE WINTER STORM WARNING IN EFFECT...OR
ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE. ALSO HAVE
THE HIGHEST CONFIDENCE IN THE H850 WARM NOSE HOLDING IN PLACE
WHILE SURFACE TEMPERATURES FALL BELOW FREEZING ALONG A COMANCHE TO
DFW TO BONHAM LINE...WHICH IS WHERE WE HAVE OUR HIGHEST FREEZING
RAIN/ICE ACCUMULATIONS FORECAST. AS MENTIONED A FEW TIMES
ALREADY...IT IS IN BETWEEN THESE LOCATIONS THAT THE PRECIPITATION
TYPE IS MOST UNCERTAIN. HAVE A WINTRY MIX FORECAST FOR THESE
LOCATIONS DUE TO A VARYING DEPTH OF THE COLD AIR BASED ON YOUR
FAVORITE MODEL OF CHOICE.
IN SUMMARY:
FORECAST PRECIPITATION AMOUNTS:
2-4 INCHES OF SNOW WITH LIGHT ACCUMULATIONS OF SLEET AND FREEZING
RAIN ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE.
ONE TENTH OF A INCH OF ICE ACCUMULATION...MAINLY RESTRICTED TO
ELEVATED ROADWAYS...WITH LESS THAN A HALF INCH OF SNOW OR SLEET
ACCUMULATION EXPECTED GENERALLY ALONG A COMANCHE TO DFW TO BONHAM
LINE.
IN BETWEEN DFW AND THE WINTER STORM WARNING...1-2 INCHES OF SNOW
AND SLEET ACCUMULATION COMBINED...AND LIGHT ACCUMULATIONS OF
FREEZING RAIN/ICE POSSIBLE.
LIGHT ICE ACCUMULATIONS WILL EXTEND ALONG A GOLDTHWAITE TO
HILLSBORO TO COOPER LINE. LITTLE TO NO ACCUMULATION OF SNOW OR
SLEET IS EXPECTED FOR THESE LOCATIONS.
TO THE SOUTHEAST OF A GOLDTHWAITE TO HILLSBORO TO COOPER
LINE...PRECIPITATION IS EXPECTED TO REMAIN ALL LIQUID AT THIS
TIME...SO NO WINTRY WEATHER IMPACTS ARE EXPECTED.
NOTE: EMBEDDED THUNDERSTORMS WILL RESULT IN LOCALLY HIGHER AMOUNTS
OF PRECIPITATION IN ALL OF THESE LOCATIONS. THUNDERSTORMS ARE MOST
LIKELY FROM THIS MORNING THROUGH THE EARLY AFTERNOON HOURS.
FOR THIS EVENING AND TONIGHT...A STRONG DRY SLOT IS EXPECTED TO
BUILD OVER THE CWA FROM SOUTHWEST TO NORTHEAST RESULTING IN AN
ABRUPT END TO PRECIPITATION BY SUNSET. TEMPERATURES ARE EXPECTED
TO FALL BELOW FREEZING ACROSS THE ENTIRE CWA OVERNIGHT...SO ANY
WET ROADWAYS WILL HAVE THE POTENTIAL TO FREEZE INTO BLACK ICE.
SUB-FREEZING TEMPERATURES OVERNIGHT WILL PROLONG ANY HAZARDOUS
ROAD CONDITIONS THAT DEVELOP DURING THE DAY TODAY ACROSS NORTH
TEXAS.
REMAINDER OF THE FORECAST...MADE NO CHANGES AT THIS TIME WITH ALL
OF OUR FOCUS ON THE NEXT 24 HOURS. WIDESPREAD RAIN SHOWERS REMAIN
ON TRACK MONDAY NIGHT INTO TUESDAY MORNING WITH LITTLE CHANCES OF
FREEZING RAIN BASED ON 00Z AND 06Z MODEL DATA. ANOTHER WINTER
STORM REMAINS ON TRACK TO IMPACT THE REGION FROM THURSDAY NIGHT
INTO FRIDAY...HOWEVER LATEST MODEL GUIDANCE HAS COME DOWN ON QPF
AMOUNTS QUITE A BIT. WE WILL STILL HAVE TO WATCH THIS LATE WEEK
STORM SYSTEM CLOSELY FOR POTENTIAL IMPACTS TO THE REGION...HOWEVER
MODELS WERE AT LEAST TRENDING TOWARDS A LOWER IMPACT EVENT.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 27 42 36 54 / 90 20 10 60 30
WACO, TX 37 28 45 38 61 / 50 10 10 50 30
PARIS, TX 35 25 42 34 48 / 100 30 10 60 50
DENTON, TX 33 24 38 34 52 / 100 20 10 60 30
MCKINNEY, TX 33 25 40 34 51 / 90 20 10 60 30
DALLAS, TX 36 27 44 37 54 / 90 20 10 60 30
TERRELL, TX 35 29 44 36 54 / 90 30 10 60 40
CORSICANA, TX 37 29 48 39 57 / 70 20 10 50 40
TEMPLE, TX 37 28 48 42 63 / 40 10 10 50 30
MINERAL WELLS, TX 33 23 39 34 54 / 100 10 10 60 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR TXZ094-
095-103>106-117>121-129>134-141>145.
WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR TXZ091>093-
100>102-115-116.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1123 AM CST SUN FEB 2 2014
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
LIFR CIGS TO PREVAIL FOR MOST OF THE AFTN IN THE WAKE OF A
DEPARTING COLD FRONT. PRECIP...FOR THE MOST PART IS COMING TO AN
END WITH THE EXCEPTION OF HOU/GLS. WINDS WILL BEGIN TO INCREASE
FOR THE COASTAL TAF SITES AS COLDER AIR MOVES IN. FOG THREAT FOR
GLS SHOULD BE ENDING IN THE NEXT 30-60 MINUTES WITH IMPROVING
VSBY. STRONG INVERSION SHOULD KEEP LIFR/MVFR CIGS IN PLACE THROUGH
THE END OF THE TAF PERIOD. MODELS SUGGEST THAT LIFR CIGS WILL
REDEVELOP OVERNIGHT AND THAT SEEMS REASONABLE WITH ABUNDANT LOW
LEVEL MOISTURE TRAPPED BENEATH A VERY STRONG INVERSION. 43
&&
.PREV DISCUSSION... /ISSUED 1000 AM CST SUN FEB 2 2014/
UPDATE...
AREAWIDE SHOWERS MOVING NORTHWARD AND LEAVING BEHIND A FEW HUNDREDTHS
TO A COUPLE OF A TENTHS OF AN INCH. 15Z SURFACE ANALYSIS HAS THE
COLD FRONT ALONG A WHARTON TO HOUSTON TO CLEVELAND LINE...SLOWLY
ADVANCING THROUGH THE CITY DURING THE HOUR AS KIAH IS 52/52...NORTH
WIND AT 14 MPH WITH LIGHT RAIN WHILE KHOU IS 70/66 WITH A SOUTH WIND
AT 7 MPH AND RAIN. THIS PRECIPITATION ACTIVITY WILL CONTINUE OVER
THE NEXT FEW HOURS...THEN WANE AND MOVE OFF TO THE EAST LATER THIS
AFTERNOON AS THE BACKING COLD AND DRY AIR MASS MOVES IN. OVERCAST
SKIES WILL REMAIN THROUGH EARLY MONDAY...GROUND HOG DAY`S MAXIMUM
TEMPERATURES HAVE ARE ALREADY BEING MET JUST DOWNSTREAM OF THE
BOUNDARY...AFTERNOON READINGS WILL REMAIN STEADY OR STEADILY FALL
THROUGH THE DAY. THE ONLY ISSUES THIS SUPER SUNDAY WILL BE LOCALLY
DENSE FOG SOUTH OF THE FRONT THIS MORNING AND A BRIEF WINDOW OF
STRONG COASTAL REGION NORTHERLIES ONCE THE FRONT ARRIVES IN THE NEXT
FEW HOURS. FRONT JUST ARRIVED IN KPSX WITH A BRISK 23 MPH NORTH
WIND. 31
PREV DISCUSSION... /ISSUED 448 AM CST SUN FEB 2 2014/
DISCUSSION...
AT 10Z/4AM...COLD FRONT JUST NW OF A KCXO/KDWH/KTME LINE. AHEAD
OF THE FRONT TEMPS ARE IN THE MID 60S WITH DEWPOINT TEMPS ABOUT
THAT MUCH. BEHIND THE FRONT KCLL/KUTS REPORTING TEMPS IN THE UPPER
40S. THE EXPECTATION IS FOR TEMPS TO CONTINUE TO DROP AS THE FRONT
PUSHES THROUGH SE TX AND OFF THE UPPER TX COAST. SUSPECT THAT MUCH
OF THE AREA WILL HAVE TEMPS IN THE 40S BY AFTERNOON WITH SHALLOW
COLD ADVECTION. COLD FRONT SHOULD SLOWLY REACH HOUSTON AREA AROUND
16Z OR 10AM AND THEN THE COAST AROUND 18Z OR 12PM. EXPECT AREAS OF
FOG TO STICK AROUND UNTIL FRONT PUSHES THROUGH. DENSE SEA FOG MAY
LINGER THROUGH THE MORNING ALONG THE COAST. THERE SHOULD BE ENOUGH
MOISTURE FOR SCT SHOWERS ACROSS THE AREA SO LIKE 60 POPS. LATEST
TRENDS IN HRRR SUPPORT THIS NOTION WITH GENERALLY 0.1-0.25 INCHES
OF PRECIP. MAY BE SOME ISO HALF INCH AMOUNTS OF RAIN WHERE SHOWERS
TRAIN ACROSS SOME OF THE SAME AREAS. POSSIBLE THAT ACTIVITY COULD
INCREASE IN COVERAGE LATER THIS MORNING INTO THE AFTERNOON AS
UPPER LEVEL LOW CURRENTLY APPROACHING THE BIG BEND MOVES EAST WITH
HEIGHT FALLS AND LARGE SCALE ASCENT SPREADING OVER THE AREA. 00Z
SOUNDING FROM KCRP SHOWS A STOUT CAP WITH 850MB TEMP AROUND 20C.
WILL KEEP SHOWERS IN FORECAST AND DOUBT THERE WILL BE ANY STRONG
DEEP CONVECTION DUE TO THE CAP. UPPER LEVEL TROUGH AXIS SWINGS
THROUGH 00Z-06Z MON SO EXPECT PRECIP TO END TOWARDS EVENING AND
OVERNIGHT.
UPPER LEVEL ANALYSIS HAS NEXT SYSTEM IN THE PACIFIC OFF THE
OREGON/CALIFORNIA COAST. THIS IS THE SYSTEM THAT SHOULD AFFECT TX
ON TUESDAY. SYSTEM SHOULD REACH S ROCKIES/WEST TX AROUND 12Z TUE.
IN RESPONSE MONDAY NIGHT EXPECT ISENTROPIC LIFT TO INCREASE WITH
DRIZZLE/LIGHT RAIN WITH SHOWERS BY 12Z TUE. MODELS ARE ALL IN
PRETTY GOOD AGREEMENT WITH UPPER LEVEL TROUGH MOVING INTO THE S
PLAINS WITH NEG TILT DURING THE DAY. PROBLEM IS THAT BEST PVA AND
LARGE SCALE LIFT WILL BE TO THE NORTH OF THE FORECAST AREA. MAY
STILL BE ENOUGH LIFT FOR SCT SHOWERS SO LIKE 50/60 POPS AGAIN FOR
TUESDAY WITH RAIN CHANCES DECREASING DURING THE AFTERNOON AS
TROUGH AXIS ROTATES BY THE AREA. MODELS ARE HAVING A TOUGH TIME
WITH SFC FEATURES NAMELY WEAK COASTAL LOW AND WARM FRONT
DEVELOPMENT. MODELS ARE KEEPING WARM FRONT JUST OFF THE COAST WITH
COASTAL LOW MOVING ACROSS UPPER TX COASTAL WATERS. ANY
THUNDERSTORM ACTIVITY IN THE WARM SECTOR SHOULD REMAIN IN THE GULF
BUT WILL ALSO HAVE TO CONTEND WITH CAPPING. ACTIVITY SHOULD CLEAR
OUT LATE TUE WITH NEXT STRONG COLD FRONT PUSHING THROUGH EARLY WED
MORNING. COLD ADVECTION WILL BE STRONG ON WED AND TEMPS SHOULD
STRUGGLE TO REACH THE LOW 50S.
GFS/ECMWF ARE TRYING TO COME INTO SOME CONSENSUS FOR THE END OF
WEEK FORECAST. UPPER LEVEL PATTERN REMAIN SOMEWHAT ZONAL WITH
POSSIBLE RIGHT ENTRANCE REGION TO JET AFFECTING THE AREA. MAY BE
ENOUGH WITH A WEAK DISTURBANCE MOVING THROUGH ON THURSDAY FOR SOME
WEAK ISENTROPIC LIFT. WILL KEEP 20/30 POPS FOR THUR BUT LOOKING
LIKE BEST CHANCES OF RAIN WILL COME ON FRIDAY. BOTH GFS/ECMWF
SHOWING A STRONGER SHORT WAVE MOVING INTO THE S ROCKIES AND TX ON
FRI. ECMWF LOOKS TO BE A BIT MORE PROGRESSIVE WHILE GFS A BIT
SLOWER AND AMPLIFIED. WILL KEEP SOME RAIN CHANCES GOING INTO SAT
AS TROUGH AXIS FINALLY PASSES THE AREA AND EXPECT CONDITIONS TO
DRY OUT. COLD FRONT WILL ALSO PUSH THROUGH TRAILING THE STRONGER
SHORTWAVE TROUGH. STILL GOING TO HAVE TO KEEP AN EYE ON TEMPS FOR
FRI MORNING. HAVE SOME AREAS WITH LOW TEMPS IN THE LOW 30S.
FORECAST WILL KEEP RAIN AS PRECIP TYPE BUT VERY WELL COULD BE
FREEZING RAIN/DRIZZLE BASED ON TOP-DOWN PRECIP METHODOLOGY. GIVEN
UNCERTAINTY IN OVERALL PATTERN FOR THE END OF THE WEEK WILL LEAVE
OUT MENTION OF ANY FROZEN PRECIP. STILL SOMETHING TO MONITOR GOING
FORWARD WITH FUTURE FORECASTS.
39
MARINE...
AREAS OF SEA FOG HAVE DEVELOPED ALONG THE COAST THIS MORNING AS
MOISTURE CONTINUES TO STREAM NORTHWARD AHEAD OF AN APPROACHING
COLD FRONT. THE FRONT HAS MOVED INTO SOUTHEAST TEXAS AND SHOULD
MOVE OFFSHORE AROUND MATAGORDA BAY BY MIDDAY AND OFFSHORE AT
GALVESTON BY EARLY AFTERNOON. STRONG NORTH WINDS AND BUILDING SEAS
ARE EXPECTED IN THE WAKE OF THIS FRONT AND ADVISORIES HAVE BEEN
ISSUED FOR THE COASTAL WATERS WITH CAUTION STATEMENTS FOR THE BAYS
BEGINNING MID AFTERNOON AND EXTENDING INTO LATE SUNDAY EVENING.
WINDS WILL BEGIN TO EASE OVERNIGHT BUT SEA HEIGHTS MAY NECESSITATE
EXTENDING THE ADVISORIES FURTHER. ONSHORE FLOW WILL REDEVELOP LATE
MONDAY AHEAD OF ANOTHER FRONTAL PASSAGE EXPECTED LATE TUESDAY. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 31 50 42 62 / 70 10 10 50 50
HOUSTON (IAH) 64 38 52 45 64 / 80 20 10 50 60
GALVESTON (GLS) 59 42 50 50 63 / 70 30 10 40 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES:
GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM 3 PM CST THIS AFTERNOON
THROUGH THIS EVENING FOR THE FOLLOWING ZONES: GALVESTON
BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...31
AVIATION/MARINE...43
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1109 AM CST SUN FEB 2 2014
.UPDATE...
AS OF 11 AM...THE FREEZING LINE EXTENDED FROM SHERMAN THROUGH
FORT WORTH ALLIANCE TO STEPHENVILLE AND COMANCHE. RADAR AND
SURFACE REPORTS SHOW A DECENT BAND OF SLEET FROM CISCO THROUGH
POSSUM KINGDOM TO NORTHWESTERN COOKE COUNTY INTO OKLAHOMA. WE
DID AN UPDATE EARLIER TO ADD JACK AND PALO PINTO COUNTIES TO THE
WINTER STORM WARNING. GIVEN THE DEW POINT DEPRESSIONS AND THE
ACTUAL TEMPERATURES TO THE IMMEDIATE NORTH...AM NOT EXPECTING A
DRAMATIC DROP IN TEMPERATURES THIS AFTERNOON. THE HEAVIEST WINTRY
PRECIPITATION SHOULD REMAIN TO THE NORTHWEST TO THE METROPLEX AS
PER THE PREVIOUS FORECAST. THE MAIN CHANGES ARE TO LOWER
TEMPERATURES SOUTH OF I-20 AND TO ADJUST THE HOURLY GRIDS.
UPDATES HAVE BEEN SENT.
58
&&
.AVIATION...
/12Z TAFS/
CONCERNS...MVFR AND IFR CIGS THROUGH THE PERIOD. WINTER
PRECIPITATION TODAY. ISOLATED CHANCES FOR THUNDER TODAY.
WIDESPREAD LIGHT RAIN IS OCCURRING ACROSS NORTH AND CENTRAL TEXAS
THIS MORNING. IN THE DFW METROPLEX...THE RAIN IS EXPECTED TO
TRANSITION TO FREEZING RAIN WITH SOME SLEET AND POSSIBLY SNOW
MIXED IN TODAY. TIMING THE CHANGEOVER FROM RAIN TO FREEZING RAIN
IS VERY CHALLENGING. THE MODELS DO NOT HAVE A GOOD HANDLE ON THE
SURFACE TEMPERATURES WHICH HAVE BEEN SLOWLY FALLING THROUGH THE
NIGHT. AREAS AROUND KAFW ARE ALREADY NEAR 32 DEGREES WITH TEMPS IN
THE LOWER TO MID 30S AS YOU MOVE WEST TO EAST ACROSS THE
METROPLEX. BASED ON THE OVERNIGHT TRENDS...THINK ALL OF THE
METROPLEX AIRPORTS WILL BE OBSERVING -FZRA BY 14Z THIS MORNING.
THE BEST CHANCES FOR SLEET OR SNOW TO MIX IN WILL BE THIS
AFTERNOON AS THE COLD AIR COLUMN DEEPENS OVER THE REGION. THE
PRECIPITATION WILL COME TO AN END LATE THIS AFTERNOON. AT
KACT...PRECIPITATION IS EXPECTED TO REMAIN ALL LIQUID RAIN AS
TEMPERATURES WILL FALL BELOW FREEZING AFTER THE RAIN HAS ENDED
THIS AFTERNOON. OVERNIGHT...TEMPERATURES WILL CONTINUE FALLING
INTO THE 20S.
STRONG NORTH WINDS BETWEEN 15-20 KTS WILL CONTINUE TODAY...
DROPPING BELOW 10 KTS LATE THIS EVENING. IN THE METROPLEX...
CEILINGS ARE CURRENTLY BETWEEN 1500-3200 FEET BUT WILL PREVAIL
BETWEEN 1000-2000 FOR MOST OF THE PERIOD. THERE IS A POTENTIAL FOR
CIGS TO FALL BELOW 1000 FEET LATE THIS MORNING AND EARLY THIS
AFTERNOON WHEN THE HEAVIEST PRECIPITATION IS EXPECTED TO OCCUR. AT
KACT...CIGS BETWEEN 1000-2000 FEET WILL PREVAIL THROUGH THE
PERIOD.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 442 AM CST SUN FEB 2 2014/
EARLY MORNING WATER VAPOR SATELLITE IMAGERY SHOWED A STRONG
SHORTWAVE TROUGH OVER THE AZ/NM/MEXICO BORDER...MOVING EAST
TOWARDS TEXAS. LARGE SCALE FORCING FOR ASCENT ASSOCIATED WITH THIS
TROUGH WAS EVIDENT OVER FAR WEST TEXAS AND THE TX PANHANDLE WHERE
A PLUME OF DEEP WATER VAPOR WAS OBSERVED DEVELOPING OUT AHEAD OF
THE TROUGH. A 00Z UPPER AIR ANALYSIS REVEALED 500 MB TEMPERATURES
OF -18 TO -20 DEG C JUST OUT AHEAD OF THE TROUGH. THIS COLD AIR
ALOFT HAD LIKELY ADVECTED OVER LOCATIONS FROM MIDLAND TO
LUBBOCK...LOWERING STABILITY ALOFT. THIS AREA CORRESPONDED WELL
WITH OBSERVED LIGHTNING STRIKES IN CELLULAR CONVECTION OBSERVED ON
REGIONAL RADARS EXTENDING FROM MIDLAND NORTHEAST TO CHILDRESS AT
0930Z. 00Z UPPER AIR ANALYSIS SHOWED THE 850 MB FREEZING LINE
HOLDING UP IN THE TX PANHANDLE...WITH A WARM MOIST AIR MASS ALOFT
OVER NORTH TEXAS AT 10 DEG C. THIS LINE HAD OBVIOUSLY SHIFTED
SOUTH IN THE 10 HRS SINCE THE WEATHER BALLOON OBSERVATIONS AS
LIGHT SNOW WAS OBSERVED AS FAR SOUTH AS SYNDER TX AT 0930Z.
FIRST...A SUMMARY OF CHANGES TO THE PREVIOUS FORECAST:
WENT AHEAD AND EXPANDED THE WINTER WEATHER ADVISORY SOUTH TO
INCLUDE MILLS...HAMILTON...BOSQUE...HILL...ELLIS...AND KAUFMAN
COUNTIES. THIS WAS DONE PRIMARILY DUE TO AN INCREASED THREAT OF
FREEZING RAIN AND LIGHT ICE ACCUMULATIONS ON ELEVATED ROAD
SURFACES THIS AFTERNOON.
EXPECT THAT ALL WINTRY PRECIPITATION WILL REMAIN ALONG AND
NORTHWEST OF A LINE FROM GOLDTHWAITE TO HILLSBORO TO COOPER. THIS
IS AS FAR SOUTHEAST AS WE HAVE THE FREEZING LINE CREEPING THIS
AFTERNOON WHILE PRECIPITATION IS STILL ACTIVE OVER THE REGION.
TEMPERATURES WILL LIKELY FALL BELOW FREEZING ACROSS ALL OF NORTH
AND CENTRAL TEXAS TONIGHT...BUT PRECIPITATION IS EXPECTED TO END
ABRUPTLY LATE THIS AFTERNOON FROM SOUTHWEST TO NORTHEAST AS A DRY
SLOT KICKS OUT OVER THE REGION ALOFT.
BEFORE THE DRY AIR ALOFT ARRIVES HOWEVER...CONFIDENCE REMAINS HIGH
THAT WE WILL SEE ENOUGH WINTRY PRECIPITATION WHERE WE ALREADY HAD
WINTRY WEATHER ADVISORIES OR A WINTER STORM WARNING IN EFFECT.
FOR LOCATIONS THAT WERE ALREADY INCLUDED IN WINTER WEATHER
ADVISORIES OR WARNINGS...THERE WERE ONLY MINOR CHANGES MADE TO
THE PREVIOUS FORECAST. THE BIGGEST CHANGE OF NOTE WAS AN INCREASE
IN THE AMOUNTS OF FREEZING RAIN/ICE ACCUMULATION FROM A FEW
HUNDREDTHS OF AN INCH TO JUST OVER A TENTH OF AN INCH IN A NARROW
BAND JUST NORTHWEST OF THE SURFACE FREEZE LINE THIS AFTERNOON.
THIS NARROW BAND OF ENHANCED ICE ACCUMULATION EXTENDS FROM
COMANCHE TO DFW TO BONHAM. THE REASONS FOR THIS WILL BE DISCUSSED
BELOW...BUT ICE ACCUMULATIONS ARE PRIMARILY EXPECTED TO REMAIN
TIED TO ELEVATED SURFACES TODAY. MOST OF THE FREEZING RAIN IS
EXPECTED TO FALL WITH TEMPERATURES IN THE 30-32 DEGREE F
RANGE...MEANING THAT MOST OF THE RAIN WILL NOT BE COLD ENOUGH TO
FREEZE ON CONTACT WITH THE RELATIVELY WARM GROUND/SOIL
TEMPERATURES WE HAVE IN PLACE ACROSS THE REGION. THIS DOES NOT
APPLY TO BRIDGES AND OVERPASSES OF COURSE AS THESE SURFACES WILL
COOL BELOW FREEZING SOON AFTER THE AIR TEMPERATURE DROPS BELOW
FREEZING TODAY.
THE FORECAST FOR SNOWFALL AMOUNTS AND LOCATIONS REMAINS LARGELY
UNCHANGED. LOCATIONS ALONG AND NORTHWEST OF A BRECKENRIDGE TO
SHERMAN LINE STILL LOOK TO BE THE MOST FAVORABLE LOCATIONS FOR 2-4
INCHES OF SNOW ACCUMULATION WITH SOME SLEET AND FREEZING RAIN
MIXED IN. A WINTER STORM WARNING REMAINS IN EFFECT FOR THESE
LOCATIONS AS A RESULT. IN BETWEEN THE DFW AREA...WHICH IS EXPECTED
TO SEE MOSTLY FREEZING RAIN AND A LATE TRANSITION TO SLEET/SNOW...
AND THE WINTER STORM WARNING...THERE REMAINS A GREAT DEAL OF
UNCERTAINTY REGARDING THE EXACT AMOUNTS OF SNOW/SLEET/FREEZING
RAIN AS THIS REPRESENTS THE LIKELY TRANSITION ZONE BETWEEN ALL 3
PRECIPITATION TYPES THROUGHOUT THE DAY TODAY. LEFT THESE AREAS IN
AN ADVISORY FOR NOW AS CONFIDENCE IN RECEIVING AMOUNTS LARGE
ENOUGH OF ANY INDIVIDUAL TYPE OF PRECIPITATION REMAINS LOW AT THIS
TIME. SUFFICE TO SAY TRAVEL WILL STILL BE A PROBLEM FOR THESE
LOCATIONS AS A MIXED BAG OF WINTRY WEATHER WILL LEAD TO SLICK
ROADWAYS...ESPECIALLY ON BRIDGES AND OVERPASSES.
SECOND...METEOROLOGICAL DISCUSSION REGARDING OUR WINTER WEATHER
EVENT:
THE SHORTWAVE TROUGH IS EXPECTED TO SWING NORTHEAST OVER THE
REGION TODAY...SPREADING LARGE SCALE FORCING FOR ASCENT OVER THE
ENTIRE CWA THIS MORNING. AS MENTIONED AT THE BEGINNING OF THE
DISCUSSION...DIFFERENTIAL ADVECTION WILL LIKELY LEAD TO A
REDUCTION IN STABILITY ALOFT FROM WEST TO EAST THROUGHOUT THE DAY
TODAY AS WELL. THIS POINT IN PARTICULAR GREATLY COMPLICATES THE
FORECAST BECAUSE PRECIPITATION AMOUNTS BECOME MUCH MORE RESPONSIVE
TO MESOSCALE FORCING AS OPPOSED TO SYNOPTIC SCALE CONSIDERATIONS.
THIS WILL RESULT IN CELLULAR CONVECTION MIXED IN BROADER
PRECIPITATION ZONES RESULTING IN LOCALLY ENHANCED PRECIPITATION
AMOUNTS FROM WHAT IS REFLECTED IN MODEL GUIDANCE AND OUR OFFICIAL
FORECAST. IN GENERAL...WE EXPECT LOW-LEVEL TEMPERATURES TO FALL
THROUGHOUT THE DAY TODAY FROM NORTHWEST TO SOUTHEAST. WARM AIR
ADVECTION WORKING AGAINST THE SOUTHWARD MOVING CANADIAN AIRMASS IS
WHAT IS DRIVING ALL OF THE DIFFERENT PRECIPITATION TYPES ACROSS
NORTH TEXAS TODAY.
MODEL FORECAST SOUNDINGS CONSISTENTLY SHOW THAT AIR PARCELS LIFTED
FROM AROUND THE 750 MB LEVEL HAVE POSITIVE CAPE ANYWHERE FROM 100
TO 250 J/KG WITH LITTLE TO NO CONVECTIVE INHIBITION PRESENT. THIS
UPRIGHT INSTABILITY WILL RESULT IN EMBEDDED THUNDERSTORMS ACROSS
THE REGION FROM THIS MORNING THROUGH EARLY THIS AFTERNOON...SO
WENT AHEAD WITH A MENTION OF ISOLATED THUNDER IN THE FORECAST AS
CONFIDENCE IS ACTUALLY PRETTY HIGH IN THIS PANNING OUT. THE MORE
IMPORTANT QUESTION IS: HOW WILL THIS AFFECT WINTER WEATHER IMPACTS
ACROSS NORTH TEXAS TODAY? THE ANSWER TO THAT QUESTION IS
TRICKY...HOWEVER IT SEEMS MOST LIKELY THAT EMBEDDED STORMS WILL
NOT CHANGE IMPACTS MUCH FROM WHAT WERE ARE CURRENTLY HIGHLIGHTING
IN OUR WINTER STORM WARNINGS AND WINTRY WEATHER ADVISORIES.
ANY EMBEDDED THUNDERSTORMS IN THE WINTER STORM WARNING AREA WILL
ONLY SERVE TO ENHANCE SNOWFALL AMOUNTS/ACCUMULATION. THESE ARE THE
LOCATIONS WE ALREADY FEEL WILL SUFFER FROM THE WORST ROAD
CONDITIONS...SO ADDITIONAL SNOWFALL WILL ONLY EXACERBATE
DETERIORATING ROAD CONDITIONS. WHILE THIS IS NOT GOOD NEWS...A
WINTER STORM WARNING IS STILL THE MOST APPROPRIATE WAY TO ADDRESS
THESE IMPACTS AND THAT WILL NOT CHANGE WITH ADDITIONAL SNOWFALL.
IF WE GET THUNDERSTORMS ALONG A COMANCHE TO DFW TO BONHAM
LINE...WHERE WE EXPECT A TENTH OF AN INCH OF FREEZING RAIN...THIS
WILL ONLY MAKE FREEZING RAIN FALL FASTER ACROSS THE AREA. WHILE
THIS SOUNDS REALLY BAD...ITS NOT OBVIOUS THAT THIS WILL RESULT IN
ADDITIONAL ICE ACCUMULATION. HEAVIER PRECIPITATION RATES WILL
LIKELY JUST CAUSE MORE OF THE PRECIPITATION TO RUN OFF AREA
ROADWAYS...AS LONG AS TEMPERATURES REMAIN IN THE 30 O 32 DEGREE F
RANGE. NOW THIS POINT IS EXTREMELY IMPORTANT...IF TEMPERATURES
WERE TO FALL INTO THE 20S WITH ENHANCED FREEZING RAIN RATES...WE
WOULD BE IN BIG TROUBLE AS ICE WOULD ACCUMULATE VERY RAPIDLY ON
AREA ROADWAYS. HOWEVER...AT THIS TIME NEARLY ALL AVAILABLE
GUIDANCE INDICATES THAT TEMPERATURES WILL REMAIN IN THIS 30 TO 32
DEGREE RANGE OVER THE DFW AREA WHILE MEASURABLE PRECIPITATION IS
FALLING. OBVIOUSLY...WE WILL HAVE TO WATCH THIS VERY CLOSELY
THROUGHOUT THE DAY TODAY.
ONCE AGAIN FOR THOSE COUNTIES IN BETWEEN DFW AND THE WINTER STORM
WARNING...THIS IS WHERE THUNDERSTORMS COULD RESULT IN THE GREATEST
DEVIATION FROM THE CURRENT FORECAST. EMBEDDED STORMS NOT ONLY
ENHANCE PRECIPITATION AMOUNTS/RATES...BUT THEY ALSO TEND TO COOL
THE ATMOSPHERE THROUGH THE DEPTH OF THEIR UPDRAFT. THIS MAY
ACTUALLY RESULT IN A COMPLETE CHANGE OVER IN PRECIPITATION TYPE
NEAR THE PRECIPITATION TYPE RESULTING IN A QUICK CHANGE OVER FROM
FREEZING RAIN TO MODERATE TO HEAVY SLEET. WE WILL WATCH FOR ANY
PERSISTENT AREAS OF THUNDERSTORMS THAT MAY LINE UP IN THIS
TRANSITION ZONE...AND MAY HAVE TO UPGRADE SOME OF THESE AREAS TO A
WINTER STORM WARNING IF IT LOOKS LIKE A CHANGE IN PRECIPITATION
TYPE WILL RESULT IN SIGNIFICANT ADDITIONAL ACCUMULATION OF SLEET
OR SNOW.
THIS BRINGS US TO THE LEAST CERTAIN PORTION OF THE FORECAST WHICH
IS THE VERTICAL THERMAL PROFILE. 00Z AND 06Z MODELS HAVE REALLY
BEEN STRUGGLING TO KEEP UP WITH AN ACCURATE DEPICTION OF THE
FREEZING LINE AT THE SURFACE. THE 00Z NAM WAS THE ONLY MODEL THAT
HAD A GOOD HANDLE ON THE 06Z FREEZING LINE AT THE SURFACE AS EVERY
OTHER MODEL THAT WAS LOOKED AT WAS ANYWHERE FROM 2-4 DEGREES TOO
WARM. THEREFORE...THIS FORECAST FOR PRECIPITATION TYPE AND SURFACE
TEMPERATURES IS HEAVILY WEIGHTED TOWARDS THE COOLER 00Z NAM.
NOTABLY...THE 06Z RAP KEPT SURFACE TEMPERATURES ABOVE FREEZING ALL
DAY ACROSS THE DFW AREA...SO THE EXACT FORECAST FOR PRECIPITATION
TYPE REMAINS AN UNCERTAIN ONE AS OF THIS MORNING.
MODELS /EVEN THE WARMEST ONES/ CONSISTENTLY SHOW THE VERTICAL
THERMAL PROFILE WILL BE COLD ENOUGH FOR MAINLY SLEET AND SNOW
WHERE WE CURRENTLY HAVE THE WINTER STORM WARNING IN EFFECT...OR
ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE. ALSO HAVE
THE HIGHEST CONFIDENCE IN THE H850 WARM NOSE HOLDING IN PLACE
WHILE SURFACE TEMPERATURES FALL BELOW FREEZING ALONG A COMANCHE TO
DFW TO BONHAM LINE...WHICH IS WHERE WE HAVE OUR HIGHEST FREEZING
RAIN/ICE ACCUMULATIONS FORECAST. AS MENTIONED A FEW TIMES
ALREADY...IT IS IN BETWEEN THESE LOCATIONS THAT THE PRECIPITATION
TYPE IS MOST UNCERTAIN. HAVE A WINTRY MIX FORECAST FOR THESE
LOCATIONS DUE TO A VARYING DEPTH OF THE COLD AIR BASED ON YOUR
FAVORITE MODEL OF CHOICE.
IN SUMMARY:
FORECAST PRECIPITATION AMOUNTS:
2-4 INCHES OF SNOW WITH LIGHT ACCUMULATIONS OF SLEET AND FREEZING
RAIN ALONG AND NORTHWEST OF A BRECKENRIDGE TO SHERMAN LINE.
ONE TENTH OF A INCH OF ICE ACCUMULATION...MAINLY RESTRICTED TO
ELEVATED ROADWAYS...WITH LESS THAN A HALF INCH OF SNOW OR SLEET
ACCUMULATION EXPECTED GENERALLY ALONG A COMANCHE TO DFW TO BONHAM
LINE.
IN BETWEEN DFW AND THE WINTER STORM WARNING...1-2 INCHES OF SNOW
AND SLEET ACCUMULATION COMBINED...AND LIGHT ACCUMULATIONS OF
FREEZING RAIN/ICE POSSIBLE.
LIGHT ICE ACCUMULATIONS WILL EXTEND ALONG A GOLDTHWAITE TO
HILLSBORO TO COOPER LINE. LITTLE TO NO ACCUMULATION OF SNOW OR
SLEET IS EXPECTED FOR THESE LOCATIONS.
TO THE SOUTHEAST OF A GOLDTHWAITE TO HILLSBORO TO COOPER
LINE...PRECIPITATION IS EXPECTED TO REMAIN ALL LIQUID AT THIS
TIME...SO NO WINTRY WEATHER IMPACTS ARE EXPECTED.
NOTE: EMBEDDED THUNDERSTORMS WILL RESULT IN LOCALLY HIGHER AMOUNTS
OF PRECIPITATION IN ALL OF THESE LOCATIONS. THUNDERSTORMS ARE MOST
LIKELY FROM THIS MORNING THROUGH THE EARLY AFTERNOON HOURS.
FOR THIS EVENING AND TONIGHT...A STRONG DRY SLOT IS EXPECTED TO
BUILD OVER THE CWA FROM SOUTHWEST TO NORTHEAST RESULTING IN AN
ABRUPT END TO PRECIPITATION BY SUNSET. TEMPERATURES ARE EXPECTED
TO FALL BELOW FREEZING ACROSS THE ENTIRE CWA OVERNIGHT...SO ANY
WET ROADWAYS WILL HAVE THE POTENTIAL TO FREEZE INTO BLACK ICE.
SUB-FREEZING TEMPERATURES OVERNIGHT WILL PROLONG ANY HAZARDOUS
ROAD CONDITIONS THAT DEVELOP DURING THE DAY TODAY ACROSS NORTH
TEXAS.
REMAINDER OF THE FORECAST...MADE NO CHANGES AT THIS TIME WITH ALL
OF OUR FOCUS ON THE NEXT 24 HOURS. WIDESPREAD RAIN SHOWERS REMAIN
ON TRACK MONDAY NIGHT INTO TUESDAY MORNING WITH LITTLE CHANCES OF
FREEZING RAIN BASED ON 00Z AND 06Z MODEL DATA. ANOTHER WINTER
STORM REMAINS ON TRACK TO IMPACT THE REGION FROM THURSDAY NIGHT
INTO FRIDAY...HOWEVER LATEST MODEL GUIDANCE HAS COME DOWN ON QPF
AMOUNTS QUITE A BIT. WE WILL STILL HAVE TO WATCH THIS LATE WEEK
STORM SYSTEM CLOSELY FOR POTENTIAL IMPACTS TO THE REGION...HOWEVER
MODELS WERE AT LEAST TRENDING TOWARDS A LOWER IMPACT EVENT.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 27 42 36 54 / 90 20 10 60 30
WACO, TX 37 28 45 38 61 / 50 10 10 50 30
PARIS, TX 35 25 42 34 48 / 100 30 10 60 50
DENTON, TX 33 24 38 34 52 / 100 20 10 60 30
MCKINNEY, TX 33 25 40 34 51 / 90 20 10 60 30
DALLAS, TX 36 27 44 37 54 / 90 20 10 60 30
TERRELL, TX 35 29 44 36 54 / 90 30 10 60 40
CORSICANA, TX 37 29 48 39 57 / 70 20 10 50 40
TEMPLE, TX 37 28 48 42 63 / 40 10 10 50 30
MINERAL WELLS, TX 33 23 39 34 54 / 100 10 10 60 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR TXZ094-
095-103>106-117>121-129>134-141>145.
WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR TXZ091>093-
100>102-115-116.
&&
$$
91/58
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
507 PM EST SUN FEB 2 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY SOUTHEAST INTO THE MOUNTAINS THIS
AFTERNOON...BUCKLING OVER INTO MORE A SOUTHWEST TO NORTHEAST
DIRECTION FROM THE SOUTHERN APPALACHIANS INTO THE TIDEWATER OF
VIRGINIA TONIGHT. LOW PRESSURE WILL TRACK ALONG THIS FRONT AND
INTO THE CAROLINAS BY LATE TONIGHT. HIGH PRESSURE MOVES ACROSS
THE OHIO VALLEY INTO THE MID ATLANTIC ON TUESDAY...WITH ANOTHER
STORM SYSTEM MOVING OVER THE REGION TUESDAY NIGHT INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 505 PM EST SUNDAY...
MINOR UPDATE TO LOWER POPS THIS EVENING IN WEST AS PRECIP TAKING
ITS TIME TO ADVANCE INTO RELATIVDELY DRY AIRMASS. RADAR MOSAIC AND
LATEST HRRR AND RAP MODELS SUGGEST ANY ACCUMULATING PRECIP MAY
HOLD OFF UNTIL LATE EVENING. TWEAKED SKY COVER AS WELL TO ADJUST
FOR PARTIAL CLEARING IN EAST WHICH MAY NOT THICKEN BACK UP UNTIL
LATE EVENING AS WELL. VERY MINOR TWEAKS TO TEMPS PER LATEST
CONDITIONS...SLOWING DOWN EVENING COOLING A BIT. OTHERWISE NO
OTHER CHANGES AT THIS POINT.
PREV DISCUSSION AS OF 235 PM EST SUNDAY...
MODELS SHOWING A MAINLY RAIN EVENT FOR OUR FORECAST AREA. THE FRONT
HAS BEEN SLOW TO MOVE THIS AFTERNOON THANKS TO THE HIGH OVER THE
SOUTHEAST...AND LACK OF KICKER UPSTREAM. SHORTWAVE ENERGY OVER TX/OK
THIS AFTERNOON WILL BE PUSHING THE FRONT EAST-SOUTHEAST THROUGH
TONIGHT...WHERE IT STALLS FROM THE SOUTHERN APPALACHIANS INTO THE VA
PIEDMONT. STRONG DYNAMICS ALOFT SUPPORT THE IDEA OF A 6-8 HOUR
WINDOW OF MODERATE AND POSSIBLY HEAVY RAIN...STARTING AFTER MIDNIGHT
IN THE WV MTNS AND SPREADING EAST INTO THE PIEDMONT BY DAWN. GOING
TO BE A TRICKY SCENARIO ACROSS OUR NRN/NWRN FRINGE OF THE CWA FROM
GREENBRIER TO AMHERST AS MODEL FLIRTING WITH THE 8H ZERO ISOTHERM
SHIFTING SE ONCE THE SURFACE LOW PASSES EAST AFTER 12Z. QUESTION IS
HOW MUCH QPF IS LEFT. AT THIS TIME WPC FAVORS LOW SNOW AMOUNTS. NOT
SEEING ANY ICE ISSUES PER MODEL SOUNDINGS...BUT COULD SEE SLEET INTO
THE MOUNTAIN EMPIRE OF TAZEWELL. HIGHER ELEVATIONS OF GREENBRIER AND
BATH INTO THE BLUE RIDGE COULD PICK UP A QUICK 1-2 INCHES OF SNOW
WITH ISOLATED 3 INCH AMOUNTS NOT OF THE QUESTION...BUT SWEET SPOT
FOR SNOW LOVERS WILL BE FURTHER NORTH OF US. JUST A COLD RAIN FOR 95
PERCENT OF OUR AREA.
TEMPS THROUGH THE PERIOD WILL STAY MOSTLY ABOVE FREEZING AS CLOUDS
START TO ENVELOP THE REGION THIS EVENING...HOLDING TEMPS UP. WE WILL
SEE DEWPOINTS INCREASE AS WELL WITH THE LIGHT RAIN SHOWERS
MOISTENING THE LOW LVLS...AND SCOURING OUT ANY RESIDUAL DRY AIR.
OVERNIGHT LOWS WILL RANGE FROM AROUND FREEZING IN THE HIGHER RIDGES
OF AMHERST TO GREENBRIER WITH MID TO UPPER 30S I-81 CORRIDOR AND
EAST TO LYH WHILE SOUTHSIDE VA INTO THE NC COUNTIES DROP TO LOWER
40S.
CLOUDS/PRECIP TOMORROW LIMIT HEATING. SUNSHINE APPEARS TO BE TOO LATE
IN HELPING IN THE WEST BUT GIVEN A LACK OF DECENT COLD ADVECTION
BEHIND THE DEPARTING LOW...WILL SEE TEMPS ON THE COOLER SIDE OF
SEASONAL NORMS BUT NOT ARCTIC COLD....RANGING FROM THE MID TO UPPER
30S OVER THE WV MOUNTAINS INTO THE ALLEGHANYS...TO LOWER TO MID 40S
FROM LYNCHBURG TO ROANOKE...ACROSS THE NEW RIVER VALLEY INTO THE NC
MOUNTAINS...WHILE SOUTHSIDE VA AND NW NC FOOTHILLS AND PIEDMONT
REACH THE UPPER 40S TO LOWER 50S.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 257 PM EST SUNDAY...
WEDGE SETTLES ACROSS THE REGION AND STRENGTHENS OVERNIGHT INTO
TUESDAY. THE NAM/MET...WHICH USUALLY DOES BEST WITH THERMAL
STRUCTURE IN WEDGES...COOLED OFF A BIT FROM PREVIOUS RUNS. JUDGING
BY THE STRENGTH AND THE DIRECTION OF THE AGEOSTROPHIC COMPONENT...AND
THE SURFACE UPSLOPE COMPONENT OF THE WINDS...THERE`S A FAIR CHANCE
THAT SUBFREEZING AIR TEMPS ARE IN PLACE ALONG THE SPINE OF THE BLUE
RIDGE FROM SW VA INTO NW NC LATE MONDAY NIGHT AND INTO TUESDAY. THIS
WOULD MEAN THAT FREEZING DRIZZLE/RAIN IS A POSSIBILITY FROM EASTERN
ASHE/WATAUGA CREEPING UP TO FLOYD COUNTY IN THE AFTERNOON. DURING
THESE EVENTS...THE WEDGE IS TYPICALLY STRONGEST IN THE
AFTERNOON...SUCH THAT TEMPS RIGHT ALONG THE BLUE RIDGE TYPICALLY
FALL DURING THE LATE MORNING AND AFTERNOON HOURS. A WET AND WARM
GROUND WOULD PROBABLY PRECLUDE ANY LIGHT ICING ON THE ROADS...MAINLY
IN THE TREES AND ELEVATED SURFACES. ONLY HAVE A FEW HUNDREDTHS OF AN
INCH OF ICE ACCUMULATION...NOTHING TO BE TOO CONCERNED ABOUT AS OF
YET...BUT SOMETHING TO WATCH...ESPECIALLY IF THE 2M NAM TEMPS
CONTINUE TO TREND COOLER AND STAY BELOW FREEZING ALL DAY AND INTO A
SIGNIFICANT PART OF TUESDAY NIGHT. BY TUESDAY EVENING...TEMPS MAY
FALL TO FREEZING IN EASTERN AND NORTHEASTERN GREENBRIER COUNTY...AND
PERHAPS ALSO THE SOUTHERN SHENANDOAH...WITH A TOUCH OF FREEZING RAIN
THERE. ELSEWHERE...IN AND OUT SHOWERS WILL BECOME MORE NUMEROUS FROM
SW TO NE BY LATE DAY TUESDAY ACROSS THE REGION. THE MAIN BODY OF
PRECIP SHOULD ARRIVE JUST AHEAD OF THE COLD FRONT WHICH SHOULD
ARRIVE WEDNESDAY MORNING TO AFTERNOON. SOME UPSLOPE FLOW SHOULD TURN
RAIN TO SNOW WITH H85 TEMPS AROUND -9C LATE DAY IN WESTERN
GREENBRIER. MUCH OF THE RAIN MAY BE OVER WITH BY WEDNESDAY AFTERNOON
ELSEWHERE. AS THE WEDGE BREAKS WEDNESDAY MORNING...CUSTOMARY GUSTS
FROM THE SSE NEAR ADVISORY CRITERIA MAY BE OBSERVED IN THE
BLF/JFX/MKJ CORRIDOR. MORE WINTERLIKE AIR ARRIVES BEHIND THE FRONT
INTO WEDNESDAY MORNING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 345 PM EST SUNDAY...
WILL START THURSDAY MORNING OFF WITH A BREAK IN THE WEATHER AS HIGH
PRESSURE BUILDS EAST ALONG THE SOUTHERN GREAT LAKES...AND THEN
PUSHES SOUTHWARD ALONG THE EASTERN FACE OF THE APPALACHIANS THURSDAY
EVENING INTO FRIDAY MORNING. THE CLEARING SKIES AND DOWNSLOPE WIND
FLOW WILL ALLOW THE SOUTHSIDE TO WARM INTO THE MID 40S FOR AFTERNOON
HIGHS...HOWEVER INCREASED CLOUD COVER AND COLDER AIR BUILDING IN
WITH THE HIGH WILL KEEP TEMPERATURES IN THE MOUNTAINS STUCK IN THE
30S. INCREASING CLOUD COVER DURING THE EVENING WILL HELP LIMIT
COOLING OVERNIGHT...AND WILL BE LOOKING FOR THURSDAY NIGHT LOWS TO
HOLD IN THE MID AND UPPER 20S MOST LOCATIONS.
BY FRIDAY MORNING...HIGH PRESSURE WILL BE FIRMLY SITUATED ALONG THE
EASTERN FACE OF THE APPALACHIANS...RESULTING IN A COOL EAST TO
SOUTHEASTERLY WIND FLOW THAT WILL NOT ALLOW FOR ALL THAT MUCH
WARMING. LONG RANGE MODELS HAVE DIFFERING OPINIONS AS TO HOW STRONG
AN UPPER LEVEL DISTURBANCE RIDING ALONG THE FRONTAL BOUNDARY TO OUR
SOUTH WILL BE...AND HOW MUCH RESULTING PRECIPITATION WILL AFFECT OUR
AREA. THE ECMWF FORECAST MODEL APPEARS VERY BULLISH WITH THE
PRECIPITATION...AND OVERDONE CONSIDERING THAT THE UPPER LEVEL
DISTURBANCE DOES NOT APPEAR VERY STRONG. THEREFORE...STICKING A
LITTLE CLOSER TO THE MORE CONSERVATIVE GFS MODEL AS FAR AS
PRECIPITATION CHANCES. BELIEVE WE WILL START THE DAY WITH LIGHT SNOW
THAT WILL GRADUALLY CHANGE TO RAIN AS WARMER AIR WORKS IN FROM THE
SOUTH.
FOR FRIDAY NIGHT AND SATURDAY...UNCERTAINTY IN THE FORECAST
INCREASES AS BOTH TIMING AND THE TRACK OF A DEVELOPING STORM SYSTEM
BEGINS TO DIFFER AMONG THE FORECAST MODELS. THE UPPER DISTURBANCE
WILL PASS TO THE EAST FRIDAY EVENING...RESULTING IN A BRIEF BREAK IN
THE PRECIPITATION FOR OUR AREA...BEFORE ANOTHER MUCH STRONGER TROUGH
BEGINS TO PUSH OUT OF THE SOUTHERN ROCKIES. SOUTHERLY FLOW AHEAD OF
THIS SYSTEM WILL PUSH WARMER GULF AIR INTO OUR AREA JUST OFF THE
SURFACE...WHILE THE HIGH PRESSURE WEDGE WILL KEEP SURFACE
TEMPERATURES AROUND THE FREEZING MARK FOR MUCH OF OUR AREA. AT THIS
POINT...LOOKING AT A COMPLEX FORECAST FOR FRIDAY NIGHT WITH RAIN
ACROSS THE PIEDMONT OF NORTH CAROLINA WHERE TEMPERATURES WILL REMAIN
ABOVE FREEZING...FREEZING RAIN NORTHWARD TO AROUND THE INTERSTATE 64
CORRIDOR...AND THEN SNOW FURTHER NORTH. TEMPERATURES WILL WARM ABOVE
FREEZING FOR MOST OF OUR AREA SATURDAY AFTERNOON...CAUSING NEARLY
ALL PRECIPITATION TO CHANGE OVER TO RAIN.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
AS OF 100 PM EST SUNDAY...
WILL START TO SEE CIGS LOWER THIS AFTERNOON FROM ROANOKE EAST.
ALREADY GETTING CIGS MVFR AT BLF AND WILL EXPECT LIGHT RAIN SOON
AT LWB/BLF BUT OVERALL NOT EXPECTING ANY CHANCE FOR LOWER THAN 6SM
VSBY...AS RADAR HAS THE HEAVIER RAIN ACROSS WRN TN AT THIS TIME.
MODELS ARE SUGGESTING THAT THE MODERATE/HEAVY RAIN WILL ARRIVE IN
THE AREA AFTER MIDNIGHT. BEFORE THEN THE LOWER LEVELS MOISTEN UP
SUCH THAT CIGS SHOULD DROP TO MVFR. AS THIS OCCURS AND LIGHT RAIN
BECOMES MORE STEADY VSBYS WILL ALSO DROP TO MVFR.
CONFIDENCE IS HIGH THAT SUB VFR CONDITIONS OCCUR OVERNIGHT INTO
MONDAY MORNING AT ALL SITES. CONFIDENCE IN SUB MVFR CONDITIONS IS
MODERATE OVER THE REGION...BUT APPEARS WILL SEE THIS AT BLF/LWB
THIS EVENING/EARLY OVERNIGHT SPREADING TO THE PIEDMONT AND
ROANOKE BY MORNING.
MAIN SLUG OF MOISTURE ALONG THE FRONT EXITS MONDAY AFTERNOON WITH
CONDITIONS IMPROVING FROM WEST TO EAST. SOME MEAGER UPSLOPE MAY
HOLD CLOUDS IN THE BLF AREA LONGER BUT LOOKS VFR AFTER 21-22Z
MONDAY.
THINGS CLEAR OUT WITH HIGH PRESSURE MOVING INTO THE AREA MONDAY
NIGHT-TUESDAY. NEXT SYSTEM ARRIVES FROM THE SOUTHWEST TUESDAY
NIGHT-WEDNESDAY WITH ANOTHER THREAT OF PRECIP AND LOWER
CIGS/VSBYS.
ANOTHER BREAK BY THURSDAY INTO EARLY FRIDAY WITH HIGH PRESSURE
ARRIVING FROM THE NORTHWEST BEFORE ANOTHER SYSTEM MOVES UP FROM
THE GULF COAST STATES FRIDAY AFTERNOON INTO THE WEEKEND.
&&
.HYDROLOGY...
AS OF 250 PM SUNDAY...
THREAT OF FLOODING ON THE RIVERS AND STREAMS STILL LOOKING
LOW...ALTHOUGH THE FROZEN...SOME THAWING GROUND...PLUS REPORTS OF
RIVER/STREAM ICE MAY LEAD TO ISOLATE PROBLEMS. FORECAST RAINFALL
AMOUNTS FROM THIS FIRST SYSTEM TONIGHT-MONDAY ARE INDICATING
GENERALLY 1 TO 1.5 INCHES...WITH HIGHER TOTALS ACROSS THE UPPER
ROANOKE BASIN AND PORTIONS AND JAMES. FORECASTS FROM SURROUNDING
RIVER FORECAST CENTERS SHOWING RIVERS COMING UP TO JUST UNDER ACTION
STAGES. ENSEMBLE FORECASTS ALSO INDICATING LOW RISK OF FLOODING.
THE NEXT SYSTEM ARRIVING LATER TUESDAY INTO TUESDAY NIGHT LOOKS LESS
ON PRECIP AMOUNTS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...SK/WP
NEAR TERM...WP
SHORT TERM...KM
LONG TERM...NF
AVIATION...WP
HYDROLOGY...WP