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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 242348
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
748 PM EDT FRI MAY 24 2013

.SYNOPSIS...
COLD FRONT WILL CONTINUE TO PUSH OFFSHORE TONIGHT AS HIGH PRESSURE
BUILDS OVER THE OHIO VALLEY. 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 SATURDAY MORNING/...
LATEST WATER VAPOR IMAGERY SHOWS DEEP UPPER TROUGH (500MB HEIGHTS
-2 STD DEV) DIGGING OVER THE ERN CONUS. AT THE SFC...COLD FRONT
HAS PUSHED OFFSHORE WITH HIGH PRESSURE BUILDING OVER THE GREAT
LAKES REGION. NARROW LINE OF SHOWERS WILL CLEAR THE COAST THE NEXT
FEW HOURS (BEFORE 5PM EDT). UPPER TROUGH AXIS WILL LOCATE ALONG
THE COAST EARLY THIS EVENING...EFFECTIVELY BRINGING AN END TO THE
PRECIP. NW WINDS 10 TO 15 MPH WITH GUSTS UP TO 25 MPH (STRONGER
NEAR THE COAST) WILL SUBSIDE LATE AFTERNOON AS SKIES CLEAR WEST TO
EAST. COLD TONIGHT AS LIGHT WINDS AND CLEARING SKIES ALLOW FOR
GOOD RADIATIONAL COOLING. TEMPS FORECAST TO FALL INTO THE LOW/MID
40S.

&&

.SHORT TERM /6 AM SATURDAY 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 CNTRL
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/...
HV AGAIN GONE CLOSE TO A ECMWF/HPC(WPC) BLEND FOR THE MIDWEEK TIME
FRAME. HV 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/"SUMMERLIKE" 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 /00Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
POTENT MID/UPR LVL TROUGH PIVOTS OFFSHORE THIS EVENING AND
OVERNIGHT. MID-LEVEL STRATUS (4-5K FT) WILL REMAIN STUBBORN ACROSS
THE VA NORTHERN NECK ONTO THE EASTERN SHORE FOR THE NEXT SEVERAL
HOURS...IF NOT MUCH OF THE OVERNIGHT HOURS...BEFORE FINALLY SCOURING
OUT. OTW...CLEAR/VFR CIGS EXPECTED AT REMAINING TAF SITES TONIGHT.
WINDS WILL CONTINUE TO DIMINISHING THRU 02Z...ENDING UP AOB 10 KT
OVERNIGHT FOR MOST TAF SITES.

VFR/DRY CONDITIONS ON SAT...BUT ALL SITES CAN EXPECT GUSTY NW
FLOW...TO 20-25 KT (25-30 KT AT KSBY). GENLY SKC WITH LIGHTER WINDS
SAT NIGHT-SUN.

GENLY DRY/VFR THROUGH MONDAY WITH INCREASING MOISTURE LATER MON-
TUE AS A WARM FRONT BEGINS TO AFFECT THE AREA. THIS WOULD BE NEXT
CHANCE FOR MORE SIGNIFICANT CIG/VSBY RESTRICTIONS.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
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 ERY 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.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...SAM
NEAR TERM...SAM
SHORT TERM...SAM
LONG TERM...MAM
AVIATION...JDM/LKB
MARINE...JDM/MAM