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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 201026
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
626 AM EDT MON MAY 20 2013

.SYNOPSIS...
A WEAK FRONT HAS PUSHED NORTH OF THE AREA WHILE HIGH PRESSURE BECOMES
ANCHORED WELL OFF THE COAST. SHOWERS AND THUNDERSTORMS WILL BECOME
MORE WIDELY SCATTERED AFTER MONDAY...WITH ABOVE AVERAGE
TEMPERATURES PREVAILING THROUGH MUCH OF THE UPCOMING WEEK. A COLD
FRONT WILL PASS THROUGH THE MID ATLANTIC STATES LATE THURSDAY INTO
EARLY FRIDAY...WITH COOLER TEMPERATURES EXPECTED BY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
FAIRLY WEAK FRONTAL BOUNDARY...IS NOW TO THE N OF THE CWA CAUSING
SFC WINDS TO BE GENERALLY FROM THE SOUTH. INCREASED POPS FOR
WESTERN AND CENTRAL PORTIONS OF THE CWA DUE TO INCREASED SHOWER
ACTIVITY VISIBLE ON RADAR...DO NOT EXPECT ANY THUNDER THROUGH THE
MORNING HOURS BUT WITH PWATS ~1.5IN...EXPECT MODERATE RAINFALL TO
OCCUR DURING ANY SHOWERS...GREATLY REDUCING VISIBILITIES.

SOME PATCHY FOG HAS DEVELOP ONCE AGAIN MONDAY MORNING...
ESPECIALLY IN AREAS NORTH OF INTERSTATE 64. WIDESPREAD DENSE FOG
IS NOT ANTICIPATED AS THE FOG SHOULD MAINLY DEVELOP FROM LOWERING
STRATUS.

EXPECT SHOWERS AND THUNDERSTORMS TO CONTINUE TO DEVELOP MONDAY
AFTN...LASTING THROUGH THE EVENING HOURS. DEW POINTS WELL INTO THE
60S WITH TEMPS RISING TO ~80 ALONG WITH MODERATE INSTABILITY WILL
FUEL THE DEVELOPMENT OF THESE STORMS. BUT...DUE TO RATHER WEAK
WIND SHEAR...NOT EXPECTING ANY SEVERE THUNDERSTORMS. NAM BUFR
SOUNDING INDICATING PWATS WILL AGAIN BE HIGH...RANGING FROM
1.60-1.75IN. WITH THAT IN MIND...ANY STORMS THAT DEVELOP WILL HAVE
HEAVY RAINFALL...CAUSING REDUCED VISIBILITIES AND HAZARDOUS
DRIVING CONDITIONS.

HIGH TEMPERATURES FOR MONDAY ARE EXPECTED TO BE NEAR 80 ACROSS THE
CWA...WHILE SLIGHTLY COOLER NEAR THE COAST.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
CONDITIONS FAIRLY SIMILAR TO MONDAY WILL PERSIST TUESDAY INTO
WEDNESDAY. S/SSW WINDS WILL DRAW WARM AND MOIST AIR FROM THE
SOUTH...AND COUPLED WITH MARGINAL INSTABILITY...WILL CREATE
FAVORABLE CONDITIONS FOR SHOWER AND THUNDERSTORM DEVELOPMENT.
PRECIPITATION COVERAGE WILL WANE EACH EVENING AS THE INSTABILITY
DECREASES. TEMPERATURES ARE FORECAST TO TOP OUT IN THE MID TO UPR
80S IN MOST AREAS WITH UPR 70S TO LWR 80S NEAR THE COAST AND OVER
THE LOWER EASTERN SHORE.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
LONG TERM PERIOD STARTS OFF WED NGT WITH A CHC FOR RAIN...MAINLY
WEST OF I-95...AHEAD OF AN APPROACHING MID-LVL TROF AND ASSOCIATED
COLD FRNT. S/SW FLOW WILL KEEP TEMPS ABOVE NORMAL...WITH LOWS IN THE
MID TO UPR 60S. THIS PATTERN CONTINUES INTO THU/THU NGT WITH STILL A
30-40% CHC FOR SHWRS/TSTMS. DEEP-LAYER MOISTURE IS ABUNDANT HOWEVER
FORCING IS A LIMITING FACTOR DUE TO A LACK OF WAA AND MOST S/W
ENERGY STAYING OFF TO THE NORTH. MODELS HAVE CONTINUED TO SPEED UP
THE TIMING OF THE FRNT...WITH THE FROPA NOW EXPECTED TO BE SOMETIME
LATE THU/THU NGT. HIGHS THU IN THE LO TO MID 80S. BEHIND THE FRNT FRI
INTO THE WEEKEND...DIMINISHING CHCS FOR RAIN AND SLGTLY LWR TEMPS
(BUT STILL AROUND SEASONAL NORMS) WITH HIGHS IN THE MID 70S TO LWR
80S AND LOWS IN THE 50S.

&&

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
CONSIDERABLY LESS STRATUS/FOG ACROSS THE AREA AND TERMINALS
TONIGHT VS. LAST NIGHT. MAIN AREA OF POTENTIAL IFR CONDITIONS
APPEARS TO BE ON THE DELMARVA. HAVE KSBY IN IFR THE NEXT 6
HOURS...BASED UPON OBSERVATION TRENDS AT KOXB/KWAL AND KGED.
ELSEWHERE...EXPECT SOME BR...AND PERHAPS SOME STRATUS
DEVELOPMENT...BUT GENERALLY VFR/MVFR CONDITIONS EXPECTED.
INCREASED LO LVL MIXING VICE LAST NIGHT ALSO EXPECTED TO INHIBIT
FOG DEVELOPMENT BEFORE SUNRISE. COULD BE A FEW SHWRS AS
WELL...BUT HAVE LEFT OUT OF MOST TERMINALS DUE TO LACK OF
DEFINITIVE TIMING.

FOR THE MOST PART...EXPECT TODAY TO BE VFR. HOWEVER...SIGNIFICANT
UNCERTAINTY EXISTS WITH REGARD TO POTENTIAL SHWR/TSTM ACTIVITY.
GIVEN INCREASED AMOUNT OF SUNSHINE EXPECTED TODAY...HAVE OPTED TO
INCLUDE PROB30 FOR TSTMS AT MOST TERMINALS IN THE 19Z TO 23Z TIME
FRAME. HEAVIER SHWRS/TSTMS WILL CAUSE BRIEF IFR CONDITIONS. EXPECT
TONIGHT TO BE SIMILAR TO CURRENT CONDITIONS...WITH MAINLY VFR/MVFR
CONDITIONS PREVAILING.

MAINLY VFR IN THE TUE TO THU TIME FRAME...WITH THE POTENTIAL FOR
ISOLD/SCTD SHWRS AND TSTMS BOTH TUE/WED. MORE WIDESPREAD SHWR/TSTM
ACTIVITY EXPECTED THU ALG/AHD OF NEXT CDFNT...WHICH MOVES ACROSS
THE AREA THU/THU NIGHT.

&&

.MARINE...
S/SSE WINDS CONTINUE ALL AREAS THIS MORNING...AS HIGH PRESSURE SFC
AND ALOFT PREVAILS OFF THE EAST COAST. THIS GENERAL PATTERN WILL
CONTINUE INTO THURSDAY. WINDS EXPECTED TO BE IN THE 10 TO 15 KT
RANGE ON THE BAY...AND AROUND 15KT ON THE OCEAN DURING MOST OF THIS
PERIOD. THUS...NO SCAS ARE ANTICIPATED THROUGH TUESDAY. CURRENT SCA
FOR SEAS ON THE NORTHERN COASTAL WATERS WILL BE ALLOWED TO EXPIRE AT
4 AM. SEAS NEAR 20 NM WILL CONTINUE TO FLIRT WITH 5
FEET...ESPECIALLY ON THE NRN COASTAL WATERS. HOWEVER...A SLOW
SUBSIDING TREND IS EXPECTED. SCTD SHWRS/TSTMS EXPECTED TODAY AND
TONIGHT...WITH A SLOW DECREASE IN COVERAGE NORTHERN AREAS ON
TUESDAY.

NEXT FRONTAL BOUNDARY WILL MOVE INTO/ACROSS THE AREA IN THE THU/FRI
TIME FRAME. LATEST GFS SUGGESTS THERE WILL BE 2 FRONTAL
PASSAGES...ONE LATE THURSDAY...THE SECOND STRONGER ONE LATE FRIDAY.
SHWRS/TSTMS EXPECTED TO ACCOMPANY BOTH FRONTS. WINDS BEHIND SECOND
BOUNDARY LIKELY TO REACH/EXCEED SCA CRITERIA FOR SEVERAL HOURS AFTER
FROPA.

&&

.HYDROLOGY...
RIVER LEVEL FORECASTS HAVE BEEN LOWERED SUBSTANTIALLY DUE TO LACK
OF SIGNIFICANT RAINFALL IN THE HEADWATERS.

&&

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

&&

$$
SYNOPSIS...LKB
NEAR TERM...DAP
SHORT TERM...DAP/LSA
LONG TERM...JEF
AVIATION...WRS
MARINE...WRS
HYDROLOGY...