Area Forecast Discussion
Issued by NWS Wakefield, VA

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000
FXUS61 KAKQ 102043
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
443 PM EDT THU JUL 10 2014

.SYNOPSIS...
A FRONTAL BOUNDARY REMAINS STALLED OVER THE REGION TONIGHT...AND
SLOWLY PUSHES SOUTH AND EAST ON FRIDAY AS A WEAK AREA OF LOW PRESSURE
MOVES NORTHEAST ALONG THIS BOUNDARY. HIGH PRESSURE BUILDS SOUTH ACROSS
THE MID ATLANTIC REGION FRIDAY NIGHT INTO SATURDAY. LOW PRESSURE
MOVES THROUGH THE GREAT LAKES ON SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST ANALYSIS INDICATES A FRONTAL BOUNDARY NOW SETUP OVER THE VA
PIEDMONT...RATHER DIFFUSE AND DIFFICULT TO FIND GIVEN ALL OF THE
CONVECTION THAT HAS AFFECTED THE REGION THUS FAR THIS AFTN. BACK
EDGE OF WIDESPREAD PRECIP AND SOME CLEARING SKIES PUSHING INTO
AREAS WEST OF I-95 NOW...BUT WITH UPPER TROUGH AXIS STILL WEST OF
THE APPALACHIANS EXPECT ANOTHER BATCH OF SHOWERS AND TSTMS TO
OVERSPREAD THE REGION LATER THIS EVENING. FARTHER EAST...SEVERE
WX HAS GENLY PUSHED OFF THE COAST FOR THE TIME BEING...ALTHOUGH
ANOTHER ROUND OF STORMS NOW PUSHING NE FROM NC AND SHOULD
OVERSPREAD INTERIOR NE NC COUNTIES AND EVENTUALLY SE VA COUNTIES
IN THE NEXT FEW HRS.

MAIN CONCERN LATER THIS EVENING AND OVERNIGHT WILL BE FOR
ADDITIONAL HEAVY RAIN...PRIMARILY IN SE VA/NE NC (SEVERE THREAT
SEEMS TO BE WANING BUT FOR NOW SEVERE TSTM WATCH REMAINS IN EFFECT
IN SE VA/NE NC). SHEARED OUT S/W ENERGY TRACKS E OF THE MTNS
OVERNIGHT AND LOOKS TO KEEP LIKELY POPS IN SE VA/NE NC EVEN WELL
AFTER MIDNIGHT...PARTICULARLY ACRS SE VA/NE NC. LOWS MID-UPPER 60S
FAR NW TO LWR-MID 70S SE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY
EXITING OFF THE COAST DURING THE AFTN. STILL ONE FINAL SHORTWAVE
TO PUSH THROUGH THE CWA FRI AFTN AND WITH AN INVERTED SFC TROUGH
REMAINING ACRS THE FAR SE ZONES WILL FOCUS HIGHEST POPS IN THESE
AREAS (HIGH CHC TO LIKELY POPS). APPEARS MUCH DRIER PER BUFKIT
SOUNDINGS OVER CENTRAL VA SO HAVE DROPPED POPS BACK TO 20-40% IN
THESE AREAS FOR MAINLY AFTN STORMS. HIGHS IN THE MID 80S E TO
UPPER 80S ALONG/WEST OF I-95. SCT EVENING POPS CONFINED TO THE FAR
SE FRI EVENING...OTHERWISE BECOMING PARTLY CLOUDY TO MOSTLY CLEAR
AND SLIGHTLY LESS HUMID. LOWS MID 60S WELL INLAND TO LWR 70S FAR SE
VA.

MODELS INDICATING THE FRONT WASHES OUT/DISSIPATES ACROSS THE AREA
SAT...AS WEAK SFC HIGH BUILDS SOUTH FROM THE NE STATES. KEPT A
20% POP OVER THE FAR NW AND IN SE VA/NE NC...BUT OVERALL SKIES
SHOULD AVG PARTLY TO MOSTLY SUNNY WITH HIGHS IN THE M-U80S. DRY
SAT NIGHT WITH LOWS MAINLY IN THE 60S. RATHER FAST MOVING SHORTWAVE
PROGGED TO PUSH ACRS THE GREAT LAKES AND NE STATES SUN...WILL
CARRY 20% POPS FOR AFTN TSTMS MOST AREAS. HIGHS 85-90 F.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGHLY ANOMALOUS FLOW WILL DEVELOP OVER THE CONUS DURING THE MEDIUM
RANGE...AS A STRONG CLOSED LOW DROPS OVER THE GREAT LAKES REGION.
THE RESULT WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE
UPPER MIDWEST TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS
SEASONABLY WARM AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE
CNTRL APPALACHIANS.

AS AN ANOMALOUS TROUGH DEVELOPS OVER THE ERN CONUS...HEIGHT FALLS
AND INCREASE WINDS ALOFT WILL RESULT IN BETTER FORCING FOR ASCENT
OVER THE LOCAL AREA. WITH A WARM/MOIST AIRMASS ALREADY IN PLACE
(MODEL DERIVED PRECIP WATERS ~ 2+ INCHES)...EXPECT BETTER COVERAGE
OF SHOWERS/THUNDERSTORMS MON AFTERNOON ALONG A SHARPENING
LEE/THERMAL TROUGH. HOWEVER...THE BEST DYNAMICS WILL REMAIN WEST OF
THE LOCAL AREA ALONG THE COLD FRONT...SO THE BEST CHANCES WILL BE IN
THE NORTH AND WEST. ANOTHER AREA OF SHOWERS/THUNDERSTORMS WILL
LIKELY DEVELOP ALONG THE TROUGH/BOUNDARIES...CLOSEST TO THE BEST
INSTABILITY. STILL SOME SUBSIDENCE/WARM AIR ALOFT VISIBLE IN
SOUNDINGS...SO WILL LEAVE AT LOW END CHANCE. HIGHS MON EXPECTED IN
THE LOW-MID 90S. WITH DEW POINTS IN THE MID-UPPER 60S...HEAT INDICES
WILL BE NEAR 100 INLAND. STRONG SPEED MAX ROUNDS THE DEEP CLOSED LOW
OVER THE GREAT LAKES TUES...EJECTING THE LOW NEWD INTO SE CANADA.
THE COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT. STRONGEST
DYNAMICS LIFT WELL NORTH OF THE REGION WITH THE CLOSED LOW...BUT
HEIGHT FALLS AND PERTURBATIONS IN THE WSW FLOW WILL RESULT IN
SCT-NUMEROUS SHOWERS/THUNDERSTORMS. BASED ON SPATIAL AND TIMING
DIFFERENCES OF THE FRONT AND STILL BEING DAY 6...WILL CAP POPS AT
CHANCE WITH THIS PACKAGE. STRONG TO SEVERE THUNDERSTORMS ALSO
POSSIBLE AS MODELS DEPICT MARGINAL SHEAR AND MLCAPE > 2500 J/KG.
ANOMALOUS TROUGH WILL PUSH THE SRN PORTION OF THE FRONT INTO THE
DEEP SOUTH...BUT THE ERN PORTION LIKELY STALLING OVER/OFF THE
MID-ATLANTIC COAST AS AN ANOMALOUS UPPER RIDGE REMAINS PARKED OVER
THE WRN ATLANTIC. WILL MAINTAIN SLIGHT CHANCE-CHANCE POPS WEDS
ACROSS THE SE AS THE FRONT WILL LIKELY LINGER OVER THE REGION. SFC
HIGH PRESSURE WILL BE SLOW TO BUILD INTO THE REGION IN WAKE OF THE
FRONT AS UPPER TROUGH REMAINS OVER THE ERN CONUS.

&&

.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
TSTMS CONTINUE ACROSS SE VA AND NE VA AS THE STRONGEST STORMS HAVE
MOVED OFF THE COAST. EXPECT SOME CLEARING THROUGH 23Z...BUT DO THINK
SHOWERS AND THUNDERSTORMS WILL REDEVELOP TONIGHT ALONG A STALLED
FRONTAL BOUNDARY. MVFR AND IFR FOG/CEILINGS ARE POSSIBLE OVERNIGHT
AS THE LOWER ATMOSPHERE REMAINS SATURATED DUE TO HEAVY RAINS AND
CONTINUED MOIST FLOW. EXPECT SHOWERS AND THUNDERSTORMS TO FORM ALONG
A SOUTHWARD SINKING FRONT FRIDAY AFTN.

FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT
FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION
LATE SUNDAY OR MONDAY.

&&

.MARINE...
STALLED FRONTAL BOUNDARY OVER CNTRL VA INTO THE DELMARVA HAS BEEN
THE FOCUS FOR SHOWERS AND THUNDERSTORMS MOVING OVER THE WATERS THIS
AFTERNOON. OUTSIDE OF THUNDERSTORM GUSTS...SPEEDS GENERALLY AOB 15
KT IN THE WATERS AND AOB 10 KT IN THE NRN BAY/COASTAL WATERS/ERN VA
RIVERS. WAVES 1-2 FT AND SEAS 2-3 FT. SUB-SCA CONDITIONS WILL
PREVAIL THRU THE OVERNIGHT AND FRIDAY AS THE BOUNDARY SLOWLY DROPS
OVER THE WATERS. THE FRONT WILL CONTINUE TO BE THE FOCUS FOR SCT
SHOWERS/THUNDERSTORMS. FLOW WILL MOSTLY BECOME SLY
TONIGHT-FRIDAY...THEN BACK TO THE NORTHEAST BEHIND THE FRONT FRI
AFTERNOON. MEANWHILE...HIGH PRESSURE BUILDS OVER NEW ENGLAND THRU
FRI...SLIDING OFF THE COAST FRIDAY NIGHT. FLOW RETURNS TO THE SOUTH
SAT NIGHT AND SUN...INCREASING SLIGHTLY TO 10-15 KT. SLY FLOW
PERSISTS THROUGH EARLY NEXT WEEK. SLY FETCH WILL PUSH SEAS IN THE
NRN WATERS TOWARD 4 FT...BUT DO NOT ANTICIPATE 5 FT SEAS ATTM. A
COLD FRONT WILL APPROACH THE WATERS MON-MON NIGHT...CROSSING THE
WATERS TUE-TUES NIGHT.

&&

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

&&

$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB/MPR
LONG TERM...SAM
AVIATION...DAP
MARINE...SAM





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