Area Forecast Discussion
Issued by NWS Wakefield, VA

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000
FXUS61 KAKQ 032044
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
344 PM EST TUE MAR 3 2015

.SYNOPSIS...
HIGH PRESSURE WILL SLIDE OFFSHORE THIS AFTERNOON. A WARM FRONT
LIFTS NORTHEAST ACROSS THE REGION TONIGHT...FOLLOWED BY A COLD
FRONT SLOWLY CROSSING THE AREA WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LATE THIS MORNG...HI PRES WAS CNTRD RIGHT ALONG THE CST. FLOW
ALOFT IS GENERALLY FM THE W...WELL OUT AHEAD OF BROAD TROF OVER
THE WRN CONUS. TEMPS WERE SLOWLY CLIMBING THRU THE 30S TO NEAR 40
DEGREES OVR THE AKQ CWA...WITH DWPTS RANGING FM THE MID TEENS TO
THE UPR 20S. RDR SHOWED ONLY VRY LGT MIXED PCPN OR RAIN OVR THE
MTNS OF WEST VA AND SW VA. CNTR OF HI PRES WILL PUSH OFFSHR THIS
AFTN...BUT LOW LEVEL CAD REMAINS OVER THE FA. A CLOUDY SKY WILL
LIMIT TEMP RISES THIS AFTN...WITH HIGHS ONLY RANGING FM THE MID
30S EXTRM NW TO THE MID 40S OVR NE NC. BETTER COVERAGE OF PCPN IS
EXPECTED MID/LATE AFTN...WITH BEST PCPN CHCS (50-60%) FOR MAINLY
LGT RAIN ACRS NRN AND WRN AREAS. MODEL SOUNDINGS CONTINUE TO
SUPPORT A BRIEF PERIOD OF -FZRA OVR FAR NW AREAS BETWEEN 16-20Z
AS TEMPS STRUGGLE TO REACH/SURPASS 32F THRU EARLY THIS AFTN.
CONFIDENCE REMAINS LOW ATTM GIVEN MARGINAL TEMPS AND A WARM DAY
YESTERDAY. OTHERWISE...P-TYPE TO BE ALL RAIN OVR THE REGION THIS
AFTN/EVENG.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WARM FRONT TO LIFT NE THROUGH THE FA TONIGHT. 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 MID/UPR
40S TO MID 50S SE.

FA BECOMES "WARM SECTORED" WED DUE TO SURGE OF A STRONG SSW FLOW.
THERE RMN TIMING ISSUES W/ THE APPROACHING CDFNT FM THE NNW...HOWEVER
A GFS/ECMWF BLEND LOOKS LIKE A GOOD COMPROMISE. WILL HAVE HIGHEST POPS
(40-70%) 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 LOW/MID 40S FAR S. TEMPS THU STEADY OR FALLING.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
EXTENDED PERIOD WILL BE HIGHLIGHTED BY GENERALLY DRY CONDITIONS
AND A RETURN TO NEAR SEASONABLE NORMAL TEMPS.

MEDIUM RANGE GUIDANCE IN GENERAL CONSENSUS WITH THE UPPER FLOW
THRU THE EXTENDED...CHARACTERIZED BY RIDGING/BLOCKING OVER THE WRN
CONUS/ERN PACIFIC AND BROAD TROUGHING OVER THE CNTRL AND ERN
CONUS. TO BEGIN THE PERIOD...COLD/DRY 1030+MB ARCTIC HIGH PRESSURE
CENTERS OVER THE MID-ATLANTIC REGION. THURSDAYS COLD FRONT LOCATES
OFF THE COAST...EXTENDING SWWD INTO THE NRN GULF. H85 TEMPS DROP
TO AROUND -8C FRI (~-1 STD DEV)...SLIGHTLY WARMER THAN DEPICTED 24
HRS AGO. HIGHS FRI GENERALLY IN THE LOW-MID 30S INLAND AND UPPER
20S-LOW 30S COASTAL AREAS. AIRMASS MODIFIES FRI NIGHT-SAT AS THE
COLD/DRY AIR RETREATS NWD. HIGH PRESSURE REMAINS OVER THE REGION
SAT...WITH LIGHT RETURN FLOW HELPING TO MODERATE LOW LEVEL
THICKNESSES. TEMPS WARM INTO THE UPPER 40S-LOW 50S INLAND AND LOW-
MID 40S COASTAL AREAS. SKY AVG MOSTLY SUNNY-PARTLY CLOUDY. HIGH
PRESSURE REMAINS OVER THE REGION SUN...RESULTING IN CONTINUED DRY
AND WARMING CONDITIONS. HIGHS IN THE LOW-MID 50S INLAND AND LOW
40S TO UPPER 40S COASTAL AREAS. ATTENTION THEN TURNS OUT
WEST...WHERE MODELS CONTINUE TO STRUGGLE HANDLING SPLIT/BLOCKY
FLOW AND SRN STREAM ENERGY OVER THE DESERT SW/BAJA. GOOD NEWS IS
THAT NOW THE DETERMINISTIC ECMWF HAS TRENDED DRY SUN NIGHT-EARLY
NEXT WEEK...MATCHING THE GFS AND ENSEMBLES. HOWEVER...SPLIT FLOW
CONTINUES RESULTING IN LOW CONFIDENCE EARLY NEXT WEEK. FRONT OVER
THE GULF WILL ATTEMPT TO AMPLIFY AND LIFT NWD AS SRN STREAM ENERGY
APPROACHES...BUT WILL KEEP POPS SILENT. HIGHS EARLY NEXT WEEK (MON
AND TUES) CONTINUE TO WARM INTO THE MID 50S INLAND AND LOW-UPPER
40S COASTAL AREAS THANKS TO COLD WATER.

&&

.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
AN OVERCAST DECK AROUND 3500-5000 FT AGL PERSISTS THIS AFTN AS
LIGHT NE WINDS START TO BECOME MORE ELY. A WARM FRONT LIFTS NORTH
THROUGH THE AREA TONIGHT. A PERIOD OF -SHRA ARE EXPECTED TO
DEVELOP AFTER 03/2100Z ACROSS MOST OF THE REGION...WITH MORE
STEADY RAINFALL ACROSS THE NRN NECK AND MD/VA EASTERN SHORE. IFR
CIGS OF 500-1000 FT AGL ARE EXPECTED TO DEVELOP AS PRECIP BEGINS
AND THEN PERSISTING THROUGH THE OVERNIGHT HOURS. THERE SHOULD BE
A BRIEF PERIOD OF IMPROVING CONDITIONS WITHIN THE WARM SECTOR WED
MORNING...ESPECIALLY OVER SE VA/NE NC WHERE THE CIGS MAY BREAK UP
NICELY. HOWEVER...A COLD FRONT IS EXPECTED TO DROP THROUGH THE
REGION WED AFTERNOON FOLLOWED BY DETERIORATING FLIGHT CONDITIONS.
THE CHANCE OF RAIN INCREASES LATER WEDNESDAY AFTERNOON...WITH RAIN
OVERSPREADING THE ENTIRE REGION WEDNESDAY EVENING. MODELS ARE
TRENDING WARMER SLIGHTLY LONGER WHICH SHOULD RESULT IN A
TRANSITION TO A WINTRY MIX WITH SLEET FROM NW TO SE AS THU
PROGRESSES AND EVENTUALLY TO ALL SNOW BY LATE THU AFTN/EARLY
EVENING. ADDITIONALLY...A GUSTY NORTHERLY WIND WILL DEVELOP ALONG
THE COAST THURSDAY. HIGH PRESSURE SETTLES OVER THE AREA FRIDAY AND
SATURDAY.

&&

.MARINE...
HIGH PRESSURE HAS CENTERED OFFSHORE THIS AFTERNOON AS A WARM
FRONT APPROACHES FROM THE SOUTH. THE RESULT IS LIGHT E-SE WINDS
AOB 10 KT OVER THE WATER. WAVES GENERALLY 1-2 FT AND SEAS 2-4 FT.
SW WINDS INCREASE TONIGHT AS A WARM FRONT LIFTS OVER THE WATERS.
LLJ INCREASES TO 50+KT TONIGHT...BUT WAA AND COLD WATER WILL
RESULT IN A SHARP INVERSION OVER THE WATER. THIS WILL PREVENT THE
HIGHER VELOCITY WINDS FROM MIXING TO THE WATER. THUS...SCA
CONDITIONS ARE NOT EXPECTED BUT CANNOT RULE OUT A FEW GUSTS OF 20
KT LATE TONIGHT. HAVE CAPPED WINDS AT 15 KT IN THE BAY AND 20 KT
IN THE COASTAL WATERS. SEAS REMAIN AOB 4 FT. COLD FRONT SLOWLY
CROSSES THE WATER NW TO SE WEDS...BECOMING NEARLY STATIONARY NEAR
THE NC/VA BORDER WEDS EVENING AS LOW PRESSURE TRACKS ALONG THE
BOUNDARY. FLOW BECOMES NLY POST FRONTAL...BUT DECREASES TO AROUND
10-15 KT AS CAA LAGS BEHIND. FRONT CLEARS THE WATERS LATE WEDS
NIGHT...WITH CAA SURGE ARRIVING INTO THE REGION LATE WEDS NIGHT.
SCA CONDITIONS EXPECTED ALL WATER THURS MORNING...PERSISTING THRU
THURS NIGHT. GUIDANCE INDICATING LOW END GALE CONDITIONS POSSIBLE
LATE THURS INTO THURS NIGHT IN THE SRN COASTAL WATERS AND
CURRITUCK SOUND...CLOSEST TO THE STRONGEST GRADIENT. SEAS BUILD TO
4-7 FT (UP TO 8 FT SRN COASTAL WATERS) THURS-THURS NIGHT. HIGH
PRESSURE BUILDS OVER THE WATERS FRI...RESULTING IN DIMINISHING
WINDS AND SLOWLY SUBSIDING SEAS. SUB-SCA CONDITIONS PREVAIL THRU
THE WEEKEND THANKS TO HIGH PRESSURE.

&&

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

&&

$$
SYNOPSIS...JDM
NEAR TERM...JDM/TMG
SHORT TERM...ALB/JDM
LONG TERM...SAM
AVIATION...AJZ
MARINE...AJZ/SAM





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