Area Forecast Discussion
Issued by NWS Sterling, VA

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943 FXUS61 KLWX 291915 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 315 PM EDT FRI APR 29 2016 .SYNOPSIS...
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STALLED FRONTAL BOUNDARY WILL WAVER ACROSS THE AREA THROUGH SATURDAY...THEN LOW PRESSURE MOVES THROUGH THE MID- ATLANTIC SUNDAY AND MONDAY. ANOTHER FRONT WILL MOVE THROUGH LATER NEXT WEEK.
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&& .NEAR TERM /THROUGH TONIGHT/...
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MRNG PCPN HAS LIFTED INTO PA. WEAK S/WV IN NW PA ATTM WL TRACK EWD TAFTN-TNGT. THERE MAY BE A FEW ASSOCD SHRA IN CWFA...BUT UPSTREAM RDR ATTM LOOKS UNIMPRESSIVE. HV BEEN TRIMMING POPS AND WL CONT TO DO SO. THE MOST NOTICEABLE ASPECT OF THE FCST WL BE THE XTNSV CLDCVR...WHICH AFFECTS MOST OF THE CWFA XCPT FOR THE CENTRAL SHEN VLY AND MUCH OF THE APLCNS. STALLED BNDRY SEEMS TO HV WIGGLED NWD. /EKN 2PM TEMP 70F WHILE DCA REMAINS AT 53F./ THE PASSAGE OF THE VORT SHUD NUDGE IT SWD AGN. FOR THE OVNGT HRS...CONTD OVERRUNNING SHUD SUPPORT DZ. THAT WL BE THE PRIMARY PCPN WORDING FOR MUCH OF THE AREA TNGT. AM HOLDING W/ PERSISTENCE WRT MIN-T...WHICH MEANS 45-50F N AND LWR 50S S.
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&& .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
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THE MOST RECENT MDL RUNS /06Z AND 12Z/ ARE TRENDING WETTER...AND THUS HV INCREASED POPS A PINCH FOR LATE DAY SAT...AND FURTHER INTO CAT TERRITORY FOR SAT NGT AND SUN. SAT CULPRIT WL BE ISENT LIFT...WHICH IMPRV THRU THE DAY. BY LT DAY...HV LKLY POPS. A SOLID SWATH OF MSTR EMINATES FM THE GLFMEX /PWAT EXCEEDS AN INCH/...WHICH SUPPORTS DECISION TO INCR TO CAT POPS BY SAT NGT...AS WELL AS INCR TO MDT RAFL IN OUR DATABASE. SFC LOPRES AND H5 VORT TRACK ALONG THE STALLED BNDRY UP THE OHVLY SUN INTO SUN NGT. THIS PATH TAKES THE BNDRY N OF THE CWA...AND DISLODGES LLVL WEDGE. AM A BIT SKEPTICAL OF FULL SCOURING DUE TO CLIMO...BUT AT THE VERY LEAST IT APPEARS AS THOUGH THERE WL BE AN ELEVATED UNSTBL LYR. ISENT LIFT/MSTR ADVCTN WL CONT TO FUEL THIS SYSTEM. AM ATTEMPTING TO PROVIDE A LTL DEFINITION BY CAPTURING A DIURNAL MIN /RELATIVELY SPEAKING/ IN THE MRNG...FLLWD BY CAT POPS WHEN DAYTIME HEATING WL HV THE BIGGER IMPACT. IN ADDITION...AM A LTL MORE EXPANSIVE IN AREA OF CHC THUNDER...AT LEAST FM AN ELEVATED SENSE. SHEAR LOOKS GOOD...BUT AM CHALLENGED TO SEE TOO MUCH SFC BASED INSTBY.
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&& .LONG TERM /MONDAY THROUGH FRIDAY/...
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LOW PRESSURE DEPARTS TO THE NORTHEAST MONDAY...BUT THE FRONTAL BOUNDARY IT RODE IN ON WILL REMAIN STALLED NEAR THE REGION THROUGH MUCH OF NEXT WEEK. MULTIPLE AREAS OF LOW PRESSURE WILL CONTINUE TO DEVELOP AND MOVE ALONG IT...AS THE LARGE SCALE TROUGH RESPONSIBLE FOR THIS ACTIVE PATTERN PERSISTS OVER EASTERN NORTH AMERICA. THIS WILL ALSO LEAD TO BELOW NORMAL TEMPERATURES THROUGH MUCH OF NEXT WEEK...WITH HIGHS STRUGGLING TO REACH 70.
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&& .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
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FLGT CONDS ON THE CUSP BTWN MVFR AND IFR. BELIEVE WL HV IMPRVMNT THRU THE AFTN BEFORE CONDS DROP ONCE AGN. HV KEPT ALL TAFS AT MVFR TNGT...ALTHO IFR /OR LWR/ CERTAINLY WITHIN THE REALM OF POSSIBILITY. CONDS WL GRDLY IMPRV ONCE AGN SAT...ALTHO FLGT RESTRICTIONS REMAIN. THERE IS A CHC AT BRIEF VFR PRIOR TO RAFL ARRIVING. ATTM CONFIDENCE TOO LOW TO CARVE OUT A WINDOW OF VFR IN THE TAFS. LT AFTN OR EVE SAT CONDS WL DROP AS RA OVERSPREADS THE AREA. RA MAY BE MDT TO BRIEFLY HVY SAT NGT INTO SUN. FLGT RESTRICTIONS WL BE WIDESPREAD. POOR FLYING CONDS CARRY OVER INTO SUN...THO BREAKS IN THE OVC PSBL AS BDRY ATTEMPTS TO WIGGLE N OF THE TERMINALS. HWVR THAT ALSO YIELDS A THUNDER RISK. SUB-VFR PSBL MON-TUE IN ANY LWR CIGS/-RA W/ FRONT STALLED NEARBY. WINDS GENERALLY NELY 10 KTS.
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&& .MARINE...
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PREV FCST REMAINS ON TRACK. ONSHORE FLOW WILL CONTINUE THROUGH SATURDAY. GENERALLY EXPECTING 5- 10 KT WITH OCCASIONAL INCREASES TO 15 KT. LIGHT FOG AND DZ WILL CONTINUE AT TIMES. NEXT ROUND OF RAIN AND ASSOCIATED LLJ REACHES WATERS BY ELY SAT EVNG. AM KEEPING WINDS UNDER SCA CRITERIA THRU SAT NGT EVEN THO WINDS ALOFT INCREASE DUE TO POOR MIXING. MIXING MAY IMPROVE ON SUN...PSBLY AFTN/EVE...BUT CONFIDENCE ON THAT RATHER LOW. THUNDERSTORMS WILL BE POSSIBLE SUNDAY AFTERNOON AND EVENING. SCA CONDITIONS ALSO REMAIN POSSIBLE SUN-MON WITH LOW PRESSURE PASSING ON MONDAY. A FRONTAL BOUNDARY STALLED NEAR OR JUST SOUTH OF THE WATERS SHOULD RESULT IN A WEAK ENOUGH GRADIENT TO PRECLUDE SMALL CRAFT ADVISORIES MONDAY INTO TUESDAY.
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&& .TIDES/COASTAL FLOODING...
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TIDAL ANOMALIES STILL AT OR BELOW A HALF-FOOT ABV NORMAL. WL CONT TO MONITOR...THERE ARE NO INDICATIONS OF POTL INUNDATION THRU THE WKND. SUN COMES THE CLOSEST.
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&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...RCM/HTS NEAR TERM...HTS SHORT TERM...HTS LONG TERM...DFH AVIATION...HTS/DFH MARINE...HTS/DFH TIDES/COASTAL FLOODING...HTS

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