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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 222022
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
422 PM EDT WED MAY 22 2013

.SYNOPSIS...
THE COMBINATION OF HIGH PRESSURE OVER THE ATLANTIC AND SOUTHWEST
WINDS WILL CONTINUE TO PULL A WARM AND HUMID AIRMASS INTO THE REGION
THROUGH THURSDAY. A COLD FRONT WILL PASS THROUGH THE MID ATLANTIC
THURSDAY NIGHT INTO FRIDAY MORNING. HIGH PRESSURE RETURNS TO THE
AREA LATE FRIDAY INTO THE WEEKEND WITH DRIER CONDITIONS AND COOLER
TEMPERATURES EXPECTED.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
HAVE MAINTAINED A CHC FOR SHWRS AND TSTMS ESPECIALLY OVER SE
AREAS THRU ERLY THIS EVENG. MAIN THREAT WILL AGAIN BE HEAVY RAIN
WITH PWATS ~1.8" AND WEAK STEERING FLOW ALOFT/FAIRLY
UNIDIRECTIONAL WINDS. COVERAGE SHUD BE LESS THAN PREVIOUS DAYS DUE
TO A LACK FORCING AND BEST INSTABILITY (NW AREAS) DISPLACED FROM
BEST MOISTURE (SE AREAS). NOT EXPECTING ANY SVR WX DUE TO MARGINAL
MID-LVL LAPSE RATES...VERY WEAK WIND SHEAR AND FORCING. WITH THE
LOSS OF DAYTIME HEATING...ANY SHWRS WILL SUBSIDE THRU THE EVENG
HRS...LEAVING MAINLY DRY CONDS FOR THE OVRNGT HRS. OTW...RAIN
CURRENTLY WEST OF THE AREA MAY CREEP INTO FAR WRN PORTIONS OF THE
FA. TEMPS REMAIN WELL ABOVE NORMAL TNGT AS SOUTHERLY FLOW
PERSISTS...LOWS IN THE UPR 60S UNDER A PRTLY TO MSTLY CLDY SKY.
PATCHY FOG IS POSSIBLE BUT MORE IN THE WAY OF LO STRATUS IS
EXPECTED. CHCS FOR RAIN WILL INCREASE THU MORNG AS MOISTURE AND
MID-LVL ENERGY EMBEDDED IN THE SW FLOW ALOFT INCREASES.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
CHCS FOR RAIN WILL INCREASE THRU THE DAY THU AS DEEP LAYER MOISTURE
INCREASES AND LO PRES APPROACHES FROM THE WEST. NOT EXPECTING
WIDESPREAD SVR WX HOWEVER AN ISO DAMAGING WING GUST IS PSBL AS
SHEAR PROFILES INCREASE AHEAD OF AN APPROACHING MID-LVL TROF.
DON`T EXPECT IT TO RAIN THE ENTIRE DAY HOWEVER COVERAGE IS ENUF TO
WARRANT LIKELY (70%) POPS. BEST TIMING FOR HEAVY RAIN WILL BE IN
THE AFTN/ERLY EVNG HRS AS MOISTURE INCREASES AND THE MID ATLANTIC
SITS UNDER THE RIGHT ENTRANCE REGION OF AN UPR-LVL JET STREAK. HI
TEMPS GENRLY IN THE LO 80S. READINGS WILL BE A BIT COOLER NEAR THE
COAST. THE RAIN WILL END FROM WEST TO EAST ERLY FRI AS THE COLD
FRNT ADVANCES OFF THE COAST. NOT EXPECTING SKIES TO COMPLETELY CLR
OUT...WITH MOISTURE STILL IN PLACE ALOFT FOLLOWING THE SFC FROPA.

DRIER CONDS EXPECTED BY FRI AFTN (THOUGH KEEPING A CHC FOR SHWRS
OVER ERN AREAS WITH THE UPR-LVL TROF STILL WEST OF THE AREA) AS
SFC FLOW BECOMES NWRLY FOR THE FIRST TIME IN SEVERAL DAYS...AND
TEMPS ONLY REACHING THE LO TO MID 70S IN MOST LOCATIONS. SFC HI
PRES BLDS IN FROM THE WEST ON SAT LEADING TO A MSTLY SNY SKY AND
NOTICEABLY COOLER TEMPS (HIGHS ONLY IN THE LO TO MID 70S).

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
-- Changed Discussion --
MEDIUM RANGE FORECAST PERIOD CHARACTERIZED BY MODIFIED CANADIAN HIGH
PRESSURE DROPPING NW TO SE ACROSS THE AREA FOR THE LATTER HALF OF
THE MEMORIAL DAY WEEKEND. ALOFT, CLOSED UPPER LEVEL LOW OVER THE
NORTHEAST AND ATLANTIC CANADA WILL ALLOW FOR MODEST HGT RISES ALOFT,
AND A GENERAL INCREMENTAL RAMPING UP OF TEMPS THROUGH THE PERIOD. IT
WILL ALSO ALLOW FOR CONTINUED NW FLOW ALOFT ACROSS THE SOUTHERN
MID-ATLANTIC SUNDAY AND MONDAY. LOW (SLIGHT CHANCE) POPS REMAIN IN
PLACE FOR MEMORIAL DAY AFTN/EVENING AS A WEAK DISTURBANCE/MID LEVEL
TROUGH DROPS ACROSS THE REGION AND A SFC WARM FRONT LIFTS NORTH
TO THE WEST.

BERMUDA HIGH/SUMMER-LIKE PATTERN RELOADS FOR THE MID TO LATTER
POTION OF THE WEEK, AS MID-UPPER LEVEL RIDGING REBUILDS ACROSS
THE EASTERN HALF OF THE CONUS AND SFC HIGH SLIDES OFFSHORE. RAINFALL
OPPORTUNITIES WILL PRIMARILY BE DIURNALLY DRIVEN MON-WED, WITH
LITTLE MORE THAN PARTLY CLOUDY AND INCREASINGLY MUGGY CONDITIONS
BY NIGHT.
-- End Changed Discussion --

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
SCT-BKN CU / SC ARND 3K FT CONTS THRU 00Z. WENT WITH A TEMPO GROUP
FOR TSRA NEXT FEW HRS BASED ON CRNT RADAR TRENDS OF SCT CONVECTION
DVLPNG ACROSS NE NC. GUSTY S-SW WINDS UP TO 20 KT.

LATEST TSCTNS SHOW PLNTY OF LOW LVL MSTR ARND AFTR 04Z FOR A STRATUS
DECK TO DVLP ONCE AGAIN. DATA EVEN SUGGESTS SOME DENSE FOG IVOF SBY
LATE TONITE. OTW...PATCHY MVFR FOG PSBL.

SLOW LIFTG OF THE CLOUD DECK THURS MORN. CDFRNT APPRCHS FROM THE
W DRNG THE AFTRN WITH PCPN ASSCTD WITH THIS FTR HOLDS OFF UNTIL
AFTR 18Z...SO KEPT PCPN OUT OF FCST FOR NOW.

OUTLOOK: FRONT PUSHES OFF THE CST DURING FRI...WITH LAGGING UPR
TROF NOT MOVNG OFFSHR UNTIL LATE FRI NGT. SO...THERE COULD BE
LINGERING LWR CIGS AND VSBYS FM SCTD PCPN RIGHT THRU FRI NGT. VFR
CONDITIONS RETURN FOR SAT AND SUN...AS HI PRES BLDS INTO AND OVR
THE REGION.

&&

.MARINE...
SCA FOR THE CHES BAY HAS BEEN DISCONTINUED AS PER LATEST OBS.
HOWEVER, HV HOISTED SCA FOR LATE TONIGHT THROUGH EARLY FRIDAY AS
WINDS /WAVES/SEAS SLOWLY RAMP UP AS PRESSURE GRADIENT TIGHTENS
BETWEEN BERMUDA HIGH AND APPROACHING COLD FRONT TO THE WEST. FRONT
WILL THEN CROSS THE WTRS LATE THU NGT INTO FRI AFTN...WITH A STRONG
NW OR N SURGE OF WINDS (~20 KT AND GUSTY) EXPECTED FRIDAY THROUGH
EARLY SATURDAY. ANOTHER PERIOD OF SCA FLAGS ARE LIKELY DURING THIS
PERIOD. CONDITIONS BECOME SCA WITH WINDS DIMINISHING AOB 15KT LATER
SAT THROUGH MONDAY AS HI PRESSURE BUILDS ACROSS THE WATERS OVER THE
HOLIDAY WEEKEND.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO MIDNIGHT EDT
     THURSDAY NIGHT FOR ANZ630>632-634.
     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT EDT
     THURSDAY NIGHT FOR ANZ650-652-654.

&&

$$
SYNOPSIS...BMD/MAS
NEAR TERM...MAS
SHORT TERM...MAS
LONG TERM...MAM
AVIATION...MPR
MARINE...MAM