605
FXUS61 KLWX 130558
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
158 AM EDT TUE AUG 13 2013
.SYNOPSIS...
A WARM FRONT WILL LIFT TO THE NORTH LATE TONIGHT AND EARLY
TUESDAY...AS AN UPPER DISTURBANCE RIDES ALONG THE FRONT. A COLD
FRONT WILL THEN MOVE ACROSS THE REGION FROM THE WEST TUESDAY
AFTERNOON AND EVENING. HIGH PRESSURE WILL BUILD INTO THE AREA
WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
HVY RAIN ORGANIZING IN WVA/ERN OH ATTM. AREA SUPPORTED BY S/WV
W/IN AMS OF 2 IN PWAT. GNRL GDNC AGREEMENT THAT THIS AREA WL CROSS
CWFA NEAR 12Z. RAFL RATES WL COME NEAR OR EXCEED FFG...SPCLY IN
PTMC HIGHLANDS AND ACRS NRN MD. FFA HAS BEEN ISSUED. FULL DSCN
WIBIS BY 4AM.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
EXPECT ONGOING CONVECTION DURING THE START OF TUESDAY...LIKELY
FOCUSED OVER THE DC-BALTIMORE METRO AREA AND POTENTIALLY HEAVY.
FRONTAL BOUNDARY IS THEN EXPECTED TO CATCH UP AND ENTER THE
HIGHLANDS DURING THE LATE MORNING/MIDDAY...MOVING THROUGH DURING
THE AFTERNOON AND EVENING. EXPECT MORE CONVECTION ALONG/AHEAD OF
THE FRONT. INTENSITY IS SOMEWHAT IN QUESTION AS INSTABILITY COULD
BE TEMPERED BY PRECIPITATION/CLOUDS EARLY...BUT IF SOME BREAKS
OCCUR THEN A FEW SEVERE STORMS MAY BE POSSIBLE FOR WIND/HAIL.
THIS MAY WIND UP BECOMING MOST LIKELY FROM I-95 EAST IN THE
AFTERNOON/EARLY EVENING.
&&
.LONG TERM /TONIGHT THROUGH MONDAY/...
XCLNT WX ON TAP FOR THE 2ND HALF OF THE WK.
BY WED MRNG...THE CDFNT SHUD HV CLRD AREA. CNDN HIPRES WL REPLACE IT
THRU THE END OF THE WK...PROVIDING 50S DEWPTS /AGN/ AND MOCLR SKIES.
WL TAKE CUE FM DEWPTS FOR MIN-T FCST. FOR MAXT...WE/LL BE SIMLR TO
THE LAST CPL PDS OF THE SAME PTTN...ARND 80F.
BY THE WKND...RTN FLOW WL BRING ELY WNDS...WHICH WL ADVECT MSTR
INLAND...SPCLY ACRS CENTRAL VA/SRN MD. THIS WL ESTABLISH AN
OVERRUNNING TYPE PTTN. INSTBY SHUD BE LMTD. THEREFORE...WL INCRS CLDS
AND KEEP SCHC/CHC POPS...WHICH WL GRDLY SPREAD NWD AS THE HIPRES
CENTER MVS OFFSHORE.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AREA OF HVY RA WL BE SPREADING EAST BY 12Z. HIEST PROB TO AFFECT
MRB/BWI/MTN. HV GNRL MVFR RESTRCITIONS IN ALL TAFS ATTM. MAY NEED
TO ADJUST LWR FOR THE N THRU THE MRNG PUSH.
COLD FRONT MOVES THROUGH FROM THE WEST DURING THE AFTERNOON WITH
MORE SHOWERS/POSSIBLE THUNDERSTORMS.
BLDG HIPRES WL SUPPORT VFR CONDS WED-FRI.
&&
.MARINE...
WEAK SOUTHERLY FLOW DEVELOPS TONIGHT IN THE WAKE OF A WARM FRONT.
DISTURBANCE MAY BRING A FEW SHOWERS/THUNDERSTORMS LATE TONIGHT
INTO EARLY TUESDAY WITH VSBY RESTRICTIONS/GUSTY WINDS. COLD FRONT
THEN MOVES THROUGH LATER IN THE AFTERNOON/EVENING. WIND SHIFT TO
THE NW OCCURS BEHIND THE FRONT...WHICH COULD BE CLOSE TO SCA
CRITERIA TUESDAY NIGHT.
MIXING WL BE FVRBL WED IN NW FLOW. THERE WL BE A SMALL WINDOW ELY
WED MRNG WHERE WNDS SUFFICIENT TO FLIRT W/ SCA CRITERIA. AFTER
THAT...SUBSIDENCE WL OVERWHELM THE GRADIENT FLOW. WL CAP WNDS AT 15
KT ATTM DUE TO THE LTMD TIMEFRAME. TIMING DOESNT HELP EITHER.
WNDS WL BE LGT THU-FRI...BCMG ONSHORE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR DCZ001.
MD...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR MDZ003>007-
009>011-013-014-501-502.
VA...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR VAZ028-031-042-
053-054.
WV...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR WVZ050>053-055-
501>506.
MARINE...NONE.
&&
$$
SYNOPSIS...BPP
NEAR TERM...HTS
SHORT TERM...BPP
LONG TERM...HTS
AVIATION...BPP/HTS/ABW
MARINE...BPP/HTS/ABW