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000
FXUS61 KLWX 121848
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
248 PM EDT SUN MAY 12 2013

.SYNOPSIS...
HIGH PRESSURE WILL BUILD TOWARD THE REGION THROUGH TUESDAY...
BRINGING DRY AND CHILLY CONDITIONS. HIGH PRESSURE WILL MOVE OFF
THE COAST DURING THE MIDDLE AND LATTER PORTION OF THE
WEEK...ALLOWING FOR A RETURN OF WARM AND HUMID CONDITIONS.

&&

.NEAR TERM /TONIGHT/...
HIGH PRES MOVG INTO THE RGN. SKIES SHOULD BE GNRLY CLR OVRNGT.
WINDS PRBLY WON`T DECOUPLE UNTIL AFTR MDNGT. AFTR THAT TEMPS
SHOULD DROP OFF - LOWS IN THE 40S FM I-95 AND E...MU30S I-95 W TO
I-81. TEMPS MAY DROP TO A30 IN THE HIGHLANDS. GROWING SEASON IS
CONSIDERED TO HV BEGUN ON MAY 5...BECAUSE OF THIS WE`VE ISSUED A
FRZ WRNG.

&&

.SHORT TERM /MONDAY/...
AS THE HIGH MOVES IN FOR MON SKIES WL BE M SUNNY. WINDS WL PICK
UP INTO THE 15-20 MPH RANGE FOR THE AFTN. HIGHS IN MOST LOCATIONS
IN THE L60S...L50S IN THE HIGHLANDS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPPER TROUGH AXIS WILL PASS THRU MON EVE BEFORE THE TROUGH MOVES OFF
THE ERN SEABOARD LATE MON NGT AND TUE. GOOD RADIATIONAL COOLING
SETUP FOR MON NGT WITH THE SFC HIGH BUILDING OVERHEAD. AN UPPER JET
STREAK APPROACHING FROM THE NW MAY BE ACCOMPANIED BY CI OVNGT...BUT
IMPACTS ON TEMPS SHOULD BE MINIMAL. MIN TEMP FCST BASED OFF A BLEND
OF BIAS-CORRECTED MOS-MAV GUIDANCE...WHICH HAVE THE HIGHEST
VERIFICATION SCORES FOR MIN TEMPS IN RECENT. ISSUED A FREEZE WATCH
FOR ALL COUNTIES WEST OF THE BLUE RIDGE. BASED ON CURRENT FCST...
FROST ADVISORIES MAY BE NEEDED FARTHER EAST TO ABOUT I-95.

UPPER RIDGE AND SFC HIPRES OVERHEAD TUE EVENTUALLY MOVES OFF THE
SOUTHEAST COAST TUE NGT AND WED. A WARM FRONT WILL MOVE THRU DURING
THIS TIME. WINDS BACKING TO SLY NEAR THE SFC AND TO WLY ALOFT WILL
YIELD STRONG WAA /12Z GFS SHOWS H8 TEMPS AT IAD INCREASING FROM -2C
TUE MRNG TO 17C BY WED EVE/. DUE TO ISENTROPIC LIFT FOLLOWED BY A
RETURN OF MOISTURE...CLOUDS AND POSSIBLY LIGHT SHOWERS OR SPRINKLES
MAY ACCOMPANY THE WARM FRONTAL PASSAGE ON WED.

A WEAK SHORTWAVE TROUGH THAT IS FCST TO TRACK EWD INTO THE SRN
PLAINS ON WED MAY BREAK DOWN THE ERN CONUS RIDGE THU AND FRI AS IT
MOVES OVER THE MID-ATLANTIC REGION. CHANCES FOR SHOWERS AND TSTMS
INCREASE LATE IN THE WEEK WITH THE APPROACH OF THE TROUGH. ABOVE
NORMAL TEMPS WILL PERSIST THRU THE WEEKEND.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR CONDS TNGT AND MON. GUSTY NW WINDS THRU SUNSET THIS EVE...AND
THEN AGN MON AFTN.

HIPRES IN CONTROL THRU MIDWEEK RESULTING IN VFR CONDITIONS. A WEAK
DISTURBANCE APPROACHES THU/FRI. GENERALLY VFR DURING THIS TIME
ALTHOUGH SHOWERS/STORMS MAY TEMPORARILY/LOCALLY RESTRICT CIGS/VSBYS.

&&

.MARINE...
SOLID SCA LVL WINDS BEING XPRNCD ON THE WATERS THIS AFTN. IT IS
DOUBTFUL THAT THESE WL DIMINISH ENTIRELY OVRNGT AS HIGH PRES WL BE
BLDG INTO THE MID ATLC RGN THRU MON. SCA IN EFFECT FOR THE LWR
PTMC AND CHES BAY S OF ANNAPOLIS OVRNGT. SCA WL BE IN EFFECT AGN
MON AFTN ONCE HTG GETS GOING AND NW WINDS CAN MIX DOWN TO THE SFC.

WINDS DIMINISH MON NGT AS HIPRES BUILDS IN. WARM FRONT MOVES THRU
WED...WHICH MARKS THE ONSET OF SLY FLOW. GIVEN DEEP MIXING...GUSTS
TO 20 KT POSSIBLE DURING THE DAY WED.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING
     FOR MDZ003-501-502.
     FREEZE WARNING FROM 2 AM TO 8 AM EDT MONDAY FOR MDZ501.
VA...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING
     FOR VAZ025>031-503-504.
     FREEZE WARNING FROM 2 AM TO 8 AM EDT MONDAY FOR VAZ503-504.
WV...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING
     FOR WVZ050>053-055-501>506.
     FREEZE WARNING FROM 2 AM TO 8 AM EDT MONDAY FOR WVZ501-503-505-
     506.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 AM EDT MONDAY FOR ANZ532>534-537-
     540-541-543.
     SMALL CRAFT ADVISORY FROM NOON TO 6 PM EDT MONDAY FOR
     ANZ530>543.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ530-
     531-535-536-538-539-542.

&&

$$
PRODUCTS...WOODY!/KLEIN