Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 251402 AAA AFDLWX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1002 AM EDT SAT JUL 25 2015 .SYNOPSIS... HIGH PRESSURE REMAINS OVER THE REGION THROUGH SUNDAY. A WEAK COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST SUNDAY AFTERNOON...THEN DISSIPATES OVER THE AREA SUNDAY NIGHT AND MONDAY. HIGH PRESSURE BUILDS BACK INTO THE REGION TUESDAY AND WEDNESDAY. ANOTHER COLD FRONT IS EXPECTED TO CROSS THE REGION ON THURSDAY BEFORE STALLING ACROSS THE CHESAPEAKE FRIDAY. && .NEAR TERM /THROUGH TONIGHT/...
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12Z IAD STILL DRY WITH ONLY 1.16 INCHES OF PWAT WITH DEEP DRY AIR ALOFT PER RAOB AND WATER VAPOR IMAGERY WITH NO SIGNS OF ANY MOISTURE ADVECTION YET WITH PREVAILING NW FLOW FROM SFC TO UPPER LEVELS. 850 MB TEMPS ARE 2C WARMER THAN 24 HRS AGO AND SUPPORT HIGHS 2-3F WARMER. MOISTURE AND HEAT INCREASE ON SUNDAY MAKING IT MORE NOTICEABLE AND UNCOMFORTABLE. CHANCE OF STORMS INCREASE DUE TO DEVELOPMENT OF A LEE-SIDE TROF.
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&& .SHORT TERM /SUNDAY/... ON SUNDAY THINGS GET JUST A BIT MORE INTERESTING. HIGH PRESSURE SHIFTS FURTHER EAST AS A WEAKENING COLD FRONT APPROACHES FROM THE NORTHWEST. THIS FRONT WILL ALREADY BE ON A SLOW BUT STEADY MARCH TOWARDS OBLIVION BY THE TIME ITS PRESENCE IS FELT IN OUR AREA...BUT WITH A WEAK BUT NOTICEABLE SHORTWAVE ACCOMPANYING ITS ARRIVAL IN THE AREA LATE SUNDAY...THE ODDS OF THUNDERSTORMS WILL DEFINITELY INCREASE ACROSS MOST OF THE REGION. MOST LIKELY SCENARIO WOULD BE STORMS FIRING CLOSE TO THE BOUNDARY WHILE IT IS STILL TO OUR NORTHWEST AND ADVECTING SOUTHEAST INTO THE REGION LATE SUNDAY INTO SUNDAY EVENING. CAPE IS NOT THAT IMPRESSIVE AND AS MENTIONED...WHILE FORCING IS PRESENT AT THE SURFACE AND ALOFT...IT IS NOT STRONG. THEREFORE...HAVE KEPT POPS BELOW LIKELY AND DO NOT EXPECT THIS WILL BE A SIGNIFICANT SEVERE WEATHER THREAT. TEMPS AND DEW POINTS SHOULD CONTINUE CLIMBING...WITH LOW 90S EXPECTED IN MOST LOWER ELEVATION LOCATIONS EAST OF THE MOUNTAINS AND DEW POINTS WELL INTO THE 60S. NOT HORRIBLE FOR JULY...JUST CLOSER TO WHAT YOU TEND TO EXPECT. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... H5 HEIGHT RISES THROUGH THURSDAY BEFORE H5 FLOW FLATTENS TO ZONAL. AT THE SURFACE...THE DISSIPATING FRONT ON MONDAY GETS REPLACED BY WEAK HIGH PRESSURE THROUGH EARLY THURSDAY. THEN A COLD FRONT PASSES ACROSS THE REGION BEFORE STALLING ACROSS DELMARVA/CHESAPEAKE REGION THURSDAY NIGHT. THE PRESCENCE OF THE FRONT AND ITS REMNANTS WILL KEEP CHC SHOWERS AND AFTERNOON TSTMS SUNDAY NIGHT THROUGH TUESDAY NIGHT PER THE 00Z GEFS. NOTHING NOTABLE IN TERMS OF CAPE THROUGH THIS PERIOD BUT WILL CONTINUE THE POTENTIAL FOR GENERAL THUNDERSTORMS THROUGH TUESDAY EVENING. AFTER THE HIGH MOVES OFF THE COAST ON THURSDAY...A FRONT APPROACHES THE REGION LATE THURSDAY...WITH DAYTIME HIGHS REACHING THE LOWER 90S. THE 00Z GEFS STALLS THE FRONT THROUGH FRIDAY...BRINGING BACK CHANCES OF SHRA/TSTMS FOR BOTH THURSDAY AND FRIDAY. WITH THE TEMPS IN THE LOWER 90S AND DEWPOINTS IN THE LOWER 70S...THERE IS A GOOD CHC OF SEEING SOME SEVERE WEATHER ON THURSDAY...WITH LESS OF A LIKELIHOOD ON FRIDAY. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
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DRY TODAY WITH A LIGHT SOUTHEAST DEVELOPING LATE TODAY AND TONIGHT. PATCHY FOG POSSIBLE AT THE USUAL SPOTS...KMRB...KCHO AND KIAD. RISK OF T-STORMS ON SUN MAINLY WEST OF I-95. POTENTIAL CONTINUES FOR PATCHY FOG MONDAY NIGHT AND TUESDAY NIGHT REDUCING VSBYS AFTER AFTERNOON SHOWER ACTIVITY.
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&& .MARINE...
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WINDS WILL BE INCREASING LATE TODAY AND TONIGHT AS SRLY CHANNELING DEVELOPS. SCA IS POSSIBLE TONIGHT BUT APPEARS MORE LIKELY ON SUN. SOUTHERLY CHANNELING UP THE CHESAPEAKE APPEARS LIKELY FOR SUNDAY NIGHT. OTHERWISE...WINDS BELOW SCA THRESHOLD THROUGH THE MARINE PERIOD.
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&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...LEE NEAR TERM...LFR SHORT TERM...RCM LONG TERM...LEE AVIATION...LEE/LFR MARINE...LEE/LFR

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