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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 180814
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
414 AM EDT SAT MAY 18 2013

.SYNOPSIS...
A WEAK FRONT REMAINS NEARLY STATIONARY OVER SOUTHWEST VIRGINIA AND NORTH
CAROLINA THROUGH SATURDAY NIGHT. THE FRONT WILL SLOWLY LIFT BACK TO THE
NORTH LATER SUNDAY INTO MONDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
QUASI-STATIONARY FRONT EXTENDS FROM THE MIDWEST INTO THE
OH VALLEY...BENDING AROUND THE LEE SIDE OF THE APPALACHIANS INTO N
CNTRL NC. SHOWERS/THUNDERSTORMS DEVELOPED ALONG THE BOUNDARY LATE
LAST NIGHT...PROGRESSING SLOWLY EWD. WHILE LOW LEVELS REMAINED
FAIRLY DRY DUE TO HIGH PRESSURE JUST OFF THE COAST...PRECIP WATER
VALUES INCREASED TO NEARLY 1.5 INCHES (+1 STD DEV) HELPING
OVERCOME THE DRY LOW LEVELS. IN ADDITION...UPPER LEVEL
DIVERGENCE...MARGINAL ELEVATED CAPE (SHOWALTER INDEX AROUND -4)
AND OMEGA ALOFT HAVE MAINTAINED THE SHOWERS/THUNDERSTORMS THIS
EVENING. EVEN WITH TEMPERATURES AT THE SFC IN THE LOW/MID 60S.
RAINFALL AMOUNTS HAVE GENERALLY RANGED FROM A FEW TENTHS OF AN
INCH UP TO AN INCH AND A HALF. BASED ON OMEGA FIELDS...EXPECT
SHOWERS TO KEEP SLOWLY PROGRESSING NEWD ACROSS THE FA THROUGH
EARLY MORNING...BEFORE COMING TO AN END MID MORNING.

FOR THIS AFTERNOON...UPPER LOW WILL LOCATE OVER THE TN VALLEY. LOW
LEVEL SW FLOW WILL INCREASE BETWEEN LOW PRESSURE OVER THE TN
VALLEY AND HIGH PRESSURE OFF THE SE COAST. RESULT WILL BE
CONTINUED ADVECTION OF ANOMALOUS PRECIP WATER VALUES INTO THE MID
ATLANTIC. ADDITIONAL WEAK IMPULSES WILL ROTATE AROUND THE SE
PERIPHERY OF THE UPPER LOW...EJECTING NEWD INTO THE MID ATLANTIC.
COMBINATION OF WEAK IMPULSES...AFTERNOON HEATING...STALLED
BOUNDARY AND DEEP MOISTURE WILL RESULT IN ADDITIONAL AFTERNOON
AND EVENING SHOWERS AND THUNDERSTORMS. BEST COVERAGE EXPECTED TO
BE OVER THE PIEDMONT THIS AFTERNOON AND THEN PROGRESSING EWD LATE
AFTERNOON INTO THE EVENING. BEST COVERAGE FOR THUNDERSTORMS
EXPECTED TO BE OVER SRN VA...CLOSEST TO BEST THETA E ADVECTION AND
WARMEST AFTERNOON TEMPS (BEST INSTABILITY). QPF AMOUNTS EXPECTED
TO RANGE FROM A FEW TENTHS OVER THE ERN SHORE TO JUST OVER HALF AN
INCH OVER THE PIEDMONT. HOWEVER...LOCALLY HIGHER AMOUNTS EXPECTED
IN HEAVIER SHOWERS/THUNDERSTORMS. ITS BEEN NEARLY A WEEK AND A
HALF SINCE THE LAST WIDESPREAD RAINFALL EVENT SO FFG IS FAIRLY
HIGH...EVEN WITH LAST NIGHTS RAINFALL. THUS...NO PLANS FOR A FFW
THIS AFTERNOON.

MOSTLY CLOUDY SKIES EXPECTED TODAY...BUT CANT RULE OUT A FEW
BREAKS HIS MORNING. NEAR SEASONABLE NORMAL TEMPS TODAY (LOW 70S
NW TO LOW 80S SE). COOLER ALONG THE IMMEDIATE COAST.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
UNSETTLED PD OF WX FOR THE WKND INTO MON. PCPN COVERAGE (AND QPF)
WILL BE PROBLEMATIC...AND TEND TO FAVOR AFTN AND EVE HRS (ESP SAT
AND AGN MON). KEY TO THE WX NEXT FEW DAYS IS WKNG LO PRES MOVING
SLOLY EWD THROUGH TN VLY W/ IT CONCENTRATED PCPN. OUT AHD OF THAT
SYS...SCT (AT BEST) PCPN FM ERN TN INTO WRN VA/TN (THIS AFTN). XPCG
THAT TO BE THE CASE HERE ON SAT (AND AWAY FM THE IMMEDIATE CST)
AS MAIN AREA OF MSTR (W/ THE REMNANT LO) RMNG PRIMARILY W OF THE
FA. SFC BNDRY DRAPED OVR NC WILL RMN NRLY STNRY THROUGH SAT...THEN
BEGIN TO PULL BACK N AS A WRMFNT INTO SUN AFTN. AT THE SAME
TIME...DEEPER MSTR ARRIVES SAT NGT...CONTS INTO SUN (MDL
TSECTIONS HAVE MUCH BETTER UVM...ESP INLAND)...RESULTING IN HIGHER
POPS (THOUGH WILL STILL KP AT CHC). DISSIPATING LO PRES INVOF FA
SUN NGT INTO MON AS LO LVL FLO BECOMES SW (WRMFNT N OF THE FA) ONCE
RESULTS IN PTNTLLY DIURNALLY DRIVEN CNVTN.

ONSHR WNDS CONT SAT...HI TEMPS SAT FM THE L70S AT THE CST TO ARND
80F ACRS INTR SRN VA AND INTR NE NC. LO TEMPS SAT NGT FM THE U50S
TO M60S. HI TEMPS SUN AGN FM THE L70S AT THE CST TO THE U70S/ARND
80F INLAND. HI TEMPS MON MNLY IN THE L/M80S (70S AT THE BEACHES).

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
LONG TERM PERIOD WILL FEATURE PERIODS OF UNSETTLED WX AND ABOVE
NORMAL HI/LO TEMPS ON AVG. FOR TUE...MID-LVL S/W TROF PUSHES
OFFSHORE ERLY IN THE DAY WITH A CHC FOR SHWRS MAINLY OVER SE AREAS.
DECREASING CLDS DURING THE AFTN WITH TEMPS CLIMBING INTO THE MID
80S. S/SW FLOW CONTINUES WED AND THU LEADING TO CONTINUED WARM TEMPS
(HIGHS IN THE MID TO UPR 80S) AND A CHC FOR MAINLY DIURNAL SHWRS/TSTMS
WITH WEAK SFC TROFS OVER THE AREA. BEST CHC FOR RAIN WILL BE FRI AS
A COLD FRNT ADVANCES TOWARDS THE AREA. WILL CAP POPS AT 40% FOR
NOW WITH HOW FAR OUT IN TIME THIS IS ALBEIT FAIRLY GOOD
CONSISTENCY AMONGST MODEL GUIDANCE WITH THE FRNTAL TIMING. HI
TEMPS ONLY IN THE UPR 70S TO NEAR 80 FRI DUE TO PRECIP AND
WIDESPREAD CLOUDINESS.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
A WEAK COLD FRONT CONTS TO BE DRAPED ACROSS THE REGION. WINDS ARE
GENERALLY FROM THE E-SE AND LESS THAN 10 KT. A FEW SCT
SHOWERS/TSTMS ARE APPROACHING FROM THE WEST AND COULD AFFECT
CENTRL VA AND RIC AROUND MIDNIGHT. SCT SHOWERS/RAIN WILL GRADUALLY
INCREASE ACROSS THE AREA DURING THE OVERNIGHT AS WEAK LOW PRES AND
AN UPPER LVL SYS APPROACHES FROM THE SW. CAN NOT RULE OUT CHC FOR
AN ISOLD TSTM OVERNIGHT ESP FOR RIC. CIGS WILL GRADUALLY LOWER TO
MVFR BY SAT DAYBREAK ACROSS CENTRL VA AND BY EARLY AFTN FOR MOST
OF THE AREA. THE FRONT WILL LINGER ACROSS THE SOUTHERN PORTIONS OF
THE CWA THRU SAT AND SUN...WITH PERIODS OF MVFR CONDS AND CHC OF
SHOWERS/TSTMS THRU THE WEEKEND.

THE FRONT WILL SLOWLY LIFT BACK N AS A WARM FRONT BY LATE
SUN/EARLY MON.

&&

.MARINE...
A WEAK FRNT WILL REMAIN JUST SOUTH OF THE AREA TNGT. NORTH OF THIS
FRNT OVER THE WATERS EXPECT EASTERLY FLOW ~10 KT WITH 1-2 FT WAVES
OVER THE BAY AND 2-3 FT SEAS OVER COASTAL WATERS. THE FRNT
STRUGGLES TO MOVE NORTHWARD SAT...SO EASTERLY FLOW WILL
CONTINUE...AND WITH A SLGTLY ENHANCED PRES GRADIENT...CUD SEE WINDS
APPROACH SCA THRESHOLDS. WILL NOT ISSUE ANY HEADLINES FOR THIS WITH
WINDS EXPECTED TO AVG 15 KT OVER THE BAY/SOUND AND 20 KT OVER
COASTAL WATERS THRU THE DAY. WINDS SLOWLY SHIFT TO THE SE SAT NGT
INTO SUN AS THE FRNT LIFTS NORTH OF THE AREA. STILL EXPECTING
SUB-SCA WINDS...ALTHO SEAS MAY APPROACH 5 FT OVER NORTHERN COASTAL
WATERS AND 4 FT OVER THE MOUTH OF THE BAY. WILL HOLD OFF ON ANY
HEADLINES FOR THIS FORECAST PACKAGE WITH IT BEING 3RD/4TH PERIOD
AND STILL SOME UNCERTAINTY. SOUTHERLY FLOW AND 4-5 FT SEAS
CONTINUES INTO ERLY TO MID NEXT WEEK.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO MIDNIGHT EDT
     TONIGHT FOR ANZ630>632-634-638.
     SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EDT
     SUNDAY FOR ANZ650-652-654.
-- End Changed Discussion --

&&

$$
SYNOPSIS...LKB
NEAR TERM...SAM
SHORT TERM...ALB
LONG TERM...MAS
AVIATION...DAP/JEF
MARINE...MAS