Area Forecast Discussion
Issued by NWS Wakefield, VA

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000
FXUS61 KAKQ 030556
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1256 AM EST TUE MAR 3 2015

.SYNOPSIS...
HIGH PRESSURE BUILDS INTO THE MID ATLANTIC STATES TONIGHT THROUGH
TUESDAY MORNING. A WARM FRONT LIFTS NORTHEAST ACROSS THE REGION
TUESDAY NIGHT...FOLLOWED BY A COLD FRONT SLOWLY CROSSING THE AREA
WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CURRENT ANALYSIS REVEALS ~1033 MB SFC HIGH PRESSURE CENTERED OVER
THE ERN GREAT LAKES...RIDGING SOUTH INTO THE MID ATLC REGION. FLOW
ALOFT IS FROM THE WNW...WELL OUT AHEAD OF BROAD TROUGHING OVER THE WRN
CONUS. SKIES ARE MAINLY CLEAR ACRS N/NE SECTIONS OF THE CWA...WHILE
MID/HIGH LEVEL CLOUDINESS IS STREAMING THROUGH THE REMAINDER OF
THE CWA. SEEING SOME LOWER CLOUDS/BKN CIGS IN NC AS WELL. FOR THE
OVERNIGHT PERIOD...AS UPPER RIDGE OVER THE MID MS VALLEY ADVANCES
EAST INTO THE OHIO VALLEY...WILL CONTINUE TO SEE INCREASING CLOUDS
INTO THE LOCAL AREA. HAVE ADJUSTED MIN TEMPS UP A FEW DEGREES ACRS
THE SOUTH DUE TO MORE CLOUD COVER...WHILE GENLY KEEPING MINS UNTOUCHED
FARTHER N/NE WHERE SKIES STAY MOSTLY CLEAR THROUGH MOST OF THE
NIGHT. EXPECT MINS TO RANGE FROM THE UPPER 20S/LOWER 30S OVER NE NC/FAR
SOUTHERN VA...TO THE LOWER 20S FROM THE NRN NECK TO THE MD ERN
SHORE. LATEST 00Z NAM12 SIMULATED REFLECTIVITY SHOWS SOME LIGHT
RETURNS ENTERING SW ZONES BY 12Z...BUT THIS WOULD JUST BE VIRGA
OVER THE DRY AIRMASS IN PLACE SO NO CHC FOR PRECIP THROUGH 12Z.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
CENTER OF SFC HI PRES SLOLY EXITS TO THE E ON TUE...BUT LO LVL CAD
RMNS OVR THE FA. CLDNS WILL CONT TO INCRS TUE MRNG LIMITING TEMP
RISE. SOME LGT PCPN MAY BREAKOUT...ESP FAR WNW AREAS...DURING THE
MIDDAY HRS...THEN BETTER COVERAGE OF PCPN ACRS FA XPCD BY MID/LT
AFTN. MDL SOUNDINGS CONT TO HINT AT PTNTL FOR BRIEF PD OF FZRA OVR
FAR NNW AREAS AS TEMPS STRUGGLE TO REACH 32F THROUGH EARLY AFTN.
CONFIDENCE RMNS LO ATTM...AND WILL HOLD OFF ON ANY WINTER WX
ADVISORY. OTRW...P-TYPE TO BE RA OVR THE RGN TUE AFTN/EVE. HI
TEMPS TO BE REACHED LT IN THE DAY...RANGING FM THE M/U30S NW-CNTRL
LOCATIONS TO L40S SE.

WARM FRONT TO LIFT NE THROUGH THE FA TUE NGT. BEST MOISTURE AND
UVM ACRS CNTRL/NRN PORTIONS OF FA...THUS THE HIGHEST POPS...W/
WITH CHC POPS LIMITED TO SRN VA/NE NC. BULK OF THE RA LIFTS TO NRN
PORTION BY LT AT NGT. LO TEMPS LIKELY ARND 00Z/04 WITH RISING TEMPS
THROUGH THE NIGHT. TEMPS BY 12Z/04 WED RISE INTO THE U40S- M50S.

FA BECOMES "WARM SECTORED" WED DUE TO SURGE OF A STRONG SSW FLOW.
THERE RMN TIMING ISSUES W/ THE APPROACHING CDFNT FM THE NNW...AS
12Z/02 NAM ABOUT 12HRS SLOWER THAN THE 12Z/02 GFS. AGAIN...THE
12Z/02 ECMWF SEEMS LIKE A GOOD COMPROMISE. WILL HAVE HIGHEST POPS
(40-60%) BY AFTN ACRS NRN TIER OF FA...W/ SLGT CHC TO CHC (20-40%)
TO THE S. FOR NOW...LEAVING OUT ANY MENTION OF T ACRS SRN VA/NE
NC...SINCE IT APRS MOST OF MOISTURE CONFINED TO W/ AND BEHIND THE
FNT. HI TEMPS FM THE U50S/L60S N TO L70S IN FAR SE VA/NE NC.

JUST ONE YEAR AGO...MARCH 2ND-3RD...WENT FM 60S TO L70S (THE 2ND)
TO A FEW INCHES OF SN (ON THE 3RD). THIS MAY OCCUR AGN THIS WK
(WED-THU).

FCST CHALLENGES CONT WED NGT THROUGH THU AS CDFNT SETTLES SSE
THROUGH THE FA...AND ANOTHER AREA OF ARCTIC SFC HI PRES BUILDS TWD
THE MS/OH VLYS. WILL LEAN TWD THE FASTER ARRIVAL OF COLDER SFC
AIR FM THE NNW (GFS/ECMWF) BY LT WED NGT AND CONTG ON THU. THE
MDLS EACH HINT AT WK SFC LO PRES TRACKING THROUGH NC AS S/W ALOFT
(IN FAST SWLY FLO) IS SHEARED AS IT MOVES EWD INTO THE RGN. ALL
THIS LEADS TO A TRANSITION (WRT P-TYPE) LT WED/THU. RA...BECOMES
MIXED W/ IP-CHANGING TO SN/IP THEN ENDING AS SN FM NNW TO SE ACRS
THE FA (LASTLY ACRS NE NC BY MID OR LT AFTN THU). TIMING THOSE
TRANSITIONS AT THIS POINT VERY DIFFICULT...THOUGH CURRENTLY EXPECT
A LEAST LGT SN ACCUMS FOR AREAS N OF THE NC/VA BORDER BEFORE THE
DAY ENDS THU (T-2 INCHES S...1-4 INCHES N (HIGHEST PTNTTLY FM
RIC-SBY)). ALONG W/ THE TRANSITION TO WINTRY PCPN...GUSTY NNE WNDS
WILL BE PUSHING COLDER AIR INTO THE RGN. LO TEMPS WED NGT FM ARND
30F N TO THE L40S FAR S. TEMPS THU STEADY OR FALLING.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
COLD TO BEGIN THE EXTENDED IN WAKE OF THURS COLD FRONT...BUT
MODERATING TEMPS THRU THE WEEKEND WILL BRING TEMPS BACK TO NEAR
NORMAL EARLY NEXT WEEK.

SHORTWAVE PUSHES OFFSHORE THURS NIGHT WITH THE NRN PORTION OF THE
FRONT PUSHING WELL OFFSHORE. SRN PORTION PUSHES SWD OVER THE GULF
STATES/NRN GULF...STALLING IN WLY FLOW ALOFT. ENDED CHANCE POPS NEAR
THE COAST AT MIDNIGHT...WITH DRYING/CLEARING CONDITIONS THEREAFTER.
1030+MB ARCTIC HIGH PRESSURE BUILDS OVER THE REGION FRI...RESULTING
IN ANOTHER COLD DAY WITH HIGHS AROUND 20 DEGS BELOW NORMAL. H85
TEMPS BOTTOM OUT AROUND -12C (-2 STD DEV)...WITH THICKNESSES
YIELDING TEMPS IN THE LOW-MID 30S. SFC HIGH PUSHES OFFSHORE FRI
NIGHT WITH LIGHT RETURN FLOW HELPING MODERATE LOW LEVEL THICKNESSES.
TEMPS FORECAST IN THE MID-UPPER TEENS FRI NIGHT UNDER MOSTLY CLEAR
SKIES. THEREAFTER...MEDIUM RANGE GUIDANCE BEGINS TO DIVERGE THANKS
TO DEVELOPING SPLIT FLOW OVER THE WRN CONUS. THE UPPER PATTERN WILL
AGAIN BE CHARACTERIZED BY CYCLONIC FLOW (TROUGHING) OVER THE ERN
CONUS AND RIDGING (RETURN TO A +PNA) OVER THE WRN CONUS. MODELS
STRUGGLING WITH A NUMBER OF CANADIAN IMPULSES SET TO IMPACT THE NE
STATES...BUT ALSO SRN STREAM ENERGY OVER THE BAJA THIS WEEKEND.
ECMWF RATHER ROBUST WITH THIS ENERGY...TRANSLATING ACROSS NRN MEXICO
AND THE SRN PLAINS SAT NIGHT-SUN...POSSIBLY PHASING WITH NRN STREAM
ENERGY OVER THE MIDWEST. THIS SOLUTION WOULD LIFT THE STALLED
FRONTAL BOUNDARY OVER THE GULF NWD LATE IN THE WEEKEND...BRINGING
RAIN TO THE REGION EARLY NEXT WEEK. THE GFS SHEARS THE
ENERGY...KEEPING IT WELL SOUTH OF THE REGION...KEEPING THE LOCAL
AREA DRY. HAVE TRENDED FORECAST TOWARD A WPC/ENSEMBLE APPROACH WHICH
KEEPS THE SRN STREAM WAVE FLAT AND THE LOCAL AREA DRY THROUGH THE
WEEKEND..WITH MODERATING TEMPS. HIGHS SAT FORECAST IN THE UPPER
40S-LOW 50S INLAND AND LOW-MID 40S NEAR THE COAST. HIGHS SUN IN THE
MID 50S INLAND AND MID-UPPER 40S NEAR THE COAST.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SCT-BKN HIGH CLOUDS SHOULD CONTINUE TO PASS OVER THE REGION
OVERNIGHT...WITH A LIGHT NNE WIND DUE TO 1030MB HIGH PRESSURE OVER
PA. ONE EXCEPTION WILL BE ECG...WHICH WILL HAVE A PERIOD OF 5KFT
CIGS OVER THE NEXT FEW HOURS. HIGH PRESSURE MOVES OFFSHORE
TODAY...FOLLOWED BY A WARM FRONT TONIGHT. A PERIOD OF -RA IS
EXPECTED TO DEVELOP LATER THIS AFTERNOON...PRIMARILY AFTER 21Z.
CIGS LOWER TO 4-5KFT THROUGH THE DAY ALONG WITH A LIGHT ESE WIND.
THERE IS AN INCREASING POTENTIAL FOR IFR CIGS TONIGHT...ESPECIALLY
AFTER 06Z AS THE WARM FRONT LIFTS THROUGH THE REGION. CONDITIONS
SHOULD IMPROVE FOR A BRIEF PERIOD LATER WEDNESDAY MORNING.
HOWEVER...A COLD FRONT IS EXPECTED TO DROP THROUGH THE REGION
DURING THE AFTERNOON FOLLOWED BY DETERIORATING FLIGHT CONDITIONS.
THE CHC OF RA INCREASES LATER WEDNESDAY AFTERNOON...WITH RA
OVERSPREADING THE ENTIRE REGION WEDNESDAY EVENING. A TRANSITION
TO A MIX AND EVENTUALLY SN SHOULD BEGIN AT SBY AFTER 06Z...WITH
THE TRANSITION OCCURRING AT RIC CLOSER TO 12Z. FARTHER SE...THE
CHANGE SHOULD OCCUR LATER IN THE DAY. ADDITIONALLY...A GUSTY
NORTHERLY WIND WILL DEVELOP ALONG THE COAST THURSDAY. HIGH
PRESSURE SETTLES OVER THE AREA FRIDAY AND SATURDAY.

&&

.MARINE...
WEAK/SECONDARY COLD FRONT HAS DROPPED SOUTH OF THE WATER THIS
AFTERNOON. WINDS HAVE BECOME NLY...BUT WEAK LOW-LEVEL CAA HAS
RESULTED IN SPEEDS GENERALLY AOB 15 KT IN THE BAY/RIVER/SOUND AND
AOB 20 KT COASTAL WATERS. THIS AS WINDS A FEW THOUSAND FT ALOFT
RANGE FROM 30-35KT. SEAS GENERALLY 2-3 FT AND WAVES 1-2 FT. HAVE
DROPPED SCA HEADLINES ALL WATER EXPECT FOR THE COASTAL WATERS SOUTH
OF THE VA/NC BORDER AS BETTER FETCH WILL RESULT IN 4-5 FT SEAS
TONIGHT. HEADLINES RUN THRU LATE TONIGHT. ~1030+MB SFC HIGH PRESSURE
BUILDS OVER THE WATER TONIGHT...SLIDING OFFSHORE TUES. FLOW BECOMES
SELY BEHIND THE DEPARTING HIGH AOB 15 KT. WARM FRONT PROGGED TO LIFT
OVER THE WATER LATE TUES NIGHT AS A COLD FRONT SLOWLY APPROACHES
FROM THE WEST. HIGH PRESSURE CENTERS OFF THE SOUTHEAST COAST. SWLY
FLOW INCREASES LATE TUES NIGHT...BUT SO DOES WAA OVER VERY COLD
WATER. MARGINAL SCA CONDITIONS ARE POSSIBLE...BUT MAYBE ONLY A FEW
GUSTS TO 20 KT LATE TUES NIGHT-EARLY WEDS MORNING IN THE BAY. SEAS
BUILD TO AROUND 5 FT 20 NM OUT LATE TUES THRU WEDS...BEFORE
SUBSIDING WEDS NIGHT AOB 4 FT. FRONT IS SLOW TO CROSS THE WATER
WEDS-WEDS NIGHT. CAA SURGES INTO THE REGION LATE WEDS
NIGHT...CONTINUING THRU THURS NIGHT. SCA CONDITIONS ARE EXPECTED
WITH A NLY WIND. SEAS BUILD TO 4-7 FT (HIGHEST IN THE SRN WATERS)
THURS...SUBSIDING FRI MORNING. HIGH PRESSURE RETURNS FRI INTO EARLY
NEXT WEEKEND.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB/LKB
SHORT TERM...ALB/MPR
LONG TERM...SAM
AVIATION...AJZ
MARINE...SAM



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