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000
FXUS61 KAKQ 250611
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
211 AM EDT SAT MAY 25 2013

.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS OVER THE OHIO VALLEY TONIGHT. HIGH
PRESSURE WILL CONTINUE TO BUILD INTO THE MID ATLANTIC THIS
WEEKEND...RESULTING IN DRY AND COOL CONDITIONS. A WARMING TREND
WILL BEGIN MEMORIAL DAY THROUGH NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A MUCH COOLER AND DRIER AIRMASS HAS MOVED INTO THE REGION THIS
EVENING. TEMPS AT 8 PM EST ARE GENERALLY IN THE MID TO UPPER 50S
AND ON TRACK TO FALL INTO THE LOW TO MID 40S OVERNIGHT UNDER
MOSTLY CLEAR SKIES. ONE AREA OF EXCEPTION WILL BE THE MD/VA
EASTERN SHORE WHERE A STRATUS DECK WILL REMAIN PERSISTENT
OVERNIGHT...PREVENTING TEMPS FROM FALLING BELOW THE MID 40S FOR
INTERIOR LOCATIONS AND NO LOWER THAN THE UPPER 40S TO LOWER 50S
ALONG THE IMMEDIATE COAST.

NW WINDS WITH GUSTS UP TO 25 MPH WILL SUBSIDE THROUGH THE EVENING
FROM WEST TO EAST. NEAR THE COAST...WINDS WILL STAY ELEVATED AND
GUSTY OVERNIGHT AS AN UPPER LEVEL TROUGH SWINGS THROUGH THE REGION
LATE TONIGHT...WHICH IS THEN QUICKLY FOLLOWED BY A 100-120 KT JET
STREAK. NW WIND GUSTS OF 30-35 MPH WILL BE COMMON ALONG COASTAL
AREAS TONIGHT INTO SATURDAY MORNING.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
UPPER PATTERN DURING THE SHORT TERM WILL BE CHARACTERIZED BY A
TROUGH IN BOTH THE WEST AND EAST WITH RIDGING OVER THE CTRL
CONUS. UPPER CLOSED LOW WILL DEVELOP OFF THE MID ATLANTIC COAST
SAT...SLOWLY LIFTING UP THE NE COAST SAT-SUN DUE TO BLOCKING OVER
THE WRN ATLANTIC. CONFLUENCE ALOFT WILL USHER IN COOL SFC HIGH
PRESSURE OVER THE WEEKEND. THE RESULTANT DEEP LAYER NWLY FLOW WILL
RESULT IN DRY...BUT COOL CONDITIONS THROUGH THE MEMORIAL DAY
WEEKEND. 850MB TEMPS WILL FALL AS LOW AS 2 STD DEV BELOW NORMAL
THIS WEEKEND...WITH TEMPS GENERALLY UPPER 60S/LOW 70S SAT AND LOW
70S SUN (-1 STD DEV). TEMPS WILL FALL INTO THE MID/UPPER 40S SAT
NIGHT AND UPPER 40S/LOW 50S SUN NIGHT.

MEANWHILE...STALLED FRONTAL BOUNDARY OVER THE NRN GULF WILL BEGIN
TO LIFT NWD LATE SUNDAY AND MONDAY...LOCATING OVER THE DEEP SOUTH
MONDAY MORNING...EXTENDING NWWD INTO THE PLAINS. UPPER RIDGE WILL
FINALLY PROGRESS EWD MON AS THE UPPER LOW OVER SE CANADA LIFTS. AS
A RESULT...A WARMING TREND WILL COMMENCE MON. AS THE RIDGE
PROGRESSES EWD...A WARM/MOIST AIRMASS WILL INTERACT WITH THE
BOUNDARY TO PRODUCE SHOWERS AND THUNDERSTORMS OVER THE MIDWEST
INTO THE OH VALLEY MONDAY AFTERNOON. ACTIVITY THEN EXPECTED TO
FORM INTO A MESOSCALE CONVECTIVE SYSTEM. MCS WILL ROUND THE
RIDGE...BUT WILL DIE OUT BEFORE REACHING THE MID-ATLANTIC.
BOUNDARY WILL CONTINUE TO LIFT NWD MONDAY NIGHT...WITH BETTER
CHANCE FOR SHOWERS AND THUNDERSTORMS IN THE EXTENDED PERIOD.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
HAVE AGAIN GONE CLOSE TO A ECMWF/HPC(WPC) BLEND FOR THE MIDWEEK TIME
FRAME. HAVE ALLOWED FOR SOME SHRAS/ISO T LATER TUESDAY AS WARM FRONT
LIFTS NORTH ACROSS THE AREA, WITH BEST CHANCES ACROSS AREAS NORTH OF
FVX/RIC/WAL LINE.

THE FRONT SHUNTS NORTH OF THE AREA FOR THE MID TO LATTER PART OF THE
WEEK. MEANWHILE, MID-UPPER LEVEL RIDGING REBUILDS ACROSS THE EASTERN
HALF OF THE CONUS AS SFC HIGH SLIDES OFF THE MID-ATLANTIC COAST.
RESULTANT BERMUDA HIGH/SUMMER-LIKE SETUP WILL ALLOW FOR INCREASING
TEMPS (AND HUMIDITY VALUES) FOR THE MID TO LATTER PART OF NEXT
WEEK. RAINFALL OPPORTUNITIES DURING THIS PERIOD WILL PRIMARILY BE
DIURNALLY DRIVEN, WITH LITTLE MORE THAN PARTLY CLOUDY AND
INCREASINGLY MUGGY CONDITIONS BY NIGHT.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
IMPRESSIVE UPR TROF FOR THIS TIME OF YEAR CURRENTLY CROSSING
AREA...AND WILL GRADUALLY LIFT AWAY FROM THE REGION THIS WEEKEND.
HIGH PRESSURE BUILDS INTO THE AREA FROM THE NW. THIS WILL PROVIDE
FOR A PROLONGED PERIOD OF VFR WITH GENERALLY SKC. AT 06Z...STILL
BKN/OVC ALTO CU ACROSS THE DELMARVA...WHICH SHOULD CLEAR IN THE
NEXT 2-4 HOURS. BIGGEST ISSUE NEXT 24 HOURS IS WIND. MOST
TERMINALS SHOULD SEE GUSTS IN THE 25-30 KT RANGE DURING THE DAY
TODAY...THEN DIMINISH AFTER 00Z SUN. WINDS SHOULD BE CONSIDERABLY
LESS ON SUNDAY...ALTHO SOME GUSTS IN THE 15 TO 20 KT RANGE WILL
STILL BE POSSIBLE.

NEXT CHC FOR CEILING/VSBY RESTRICTIONS WILL BE LATER MON-TUE AS A
WARM FRONT BEGINS TO AFFECT THE AREA...WITH INCREASING MOISTURE.

&&

.MARINE...
GALE WARNING CURRENTLY IN PLACE OVER THE NORTHERN BAY ZONES AND
FAR NORTHERN COASTAL ZONES. WIND GUSTS ARE VERY CLOSE TO GALE IN
THESE AREAS ATTM...AND WITH STRONGEST SURGE OF CAA JUST NOT
ARRIVING...EXPECT PREDOMINATE GUSTS TO GALE FOR A FEW HRS BETWEEN
00Z/8P AND 10Z/6A. HAVE RUN HEADLINE THROUGH 15Z/11A FOR NOW...WITH
THE IDEA THAT OVERNIGHT CREW CAN KEEP AN EYE ON OBS AND EXPIRE
EARLY AS NEEDED.

SEAS WILL RUN ON THE ORDER OF 5-8 FT ON THE COASTAL WATERS...WAVES
~2 FT ON THE SOUND...2-3 FT ON THE RIVERS...3-5 IN THE LOWER CHES
BAY. PERIOD OF SCA FLAGS WILL BE RE-ISSUED AS SOON AS GALES ARE
EXPIRED AS DEVELOPING LOW PRESSURE OFF NJ/SRN NEW ENG COAST SLOWLY
LIFTS TO THE NE INTO SUN...RESULTING IN ONLY GRADUAL IMPROVEMENT
(SCA PER WAVEWATCH POTENTIALLY TO LINGER OVR THE NRN OCN WTRS INTO
LATE SAT). SCA FLAGS DROP OFF OVER ALL BUT COASTAL AREAS SAT
NIGHT...EXTENDING INTO EARLY SUNDAY OVER NRN COASTAL ZONES.

FAR MORE FAVORABLE BOATING CONDITIONS EXPECTED FOR THE LATTER HALF
OF THE HOLIDAY WEEKEND AS HIGH PRESSURE BUILDS IN FROM THE NW. WINDS
AND SEAS WILL GRADUALLY DIMINISH THROUGH THIS PD WITH W WINDS AOB 15
KT.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ633-
     635>638.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ632-634-
     654-656-658.
     GALE WARNING UNTIL 11 AM EDT THIS MORNING FOR ANZ630-631-650-
     652.

&&

$$
SYNOPSIS...SAM
NEAR TERM...BMD/SAM
SHORT TERM...SAM
LONG TERM...MAM
AVIATION...WRS
MARINE...MAM/WRS