Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 040136 AAA AFDLWX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 936 PM EDT MON AUG 3 2015 .SYNOPSIS... A COLD FRONT WILL GRADUALLY PUSH SOUTHEAST INTO THE AREA TONIGHT AND TUESDAY. THE FRONT WILL SLIDE SOUTH OF THE AREA TUESDAY NIGHT ALLOWING HIGH PRESSURE TO BUILD IN WEDNESDAY. THE FRONT WILL PUSH BACK NORTH INTO THE AREA ON THURSDAY AS A WAVE OF LOW PRESSURE RIDES EASTWARD ALONG IT. THIS LOW WILL CLEAR THE AREA FRIDAY TAKING THE FRONT WITH IT. HIGH PRESSURE WILL BUILD IN BEHIND IT AND DOMINATE OVER THE WEEKEND. && .NEAR TERM /THROUGH TUESDAY/...
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STORMS OVER SCNTRL PA HAVE PRETTY MUCH DISSIPATED. OTHER STORMS OVER WRN PA EXPECTED TO TRACK MAINLY EAST AND STAY WELL NORTH. IT DOESN`T LOOK LIKE WE`LL SAY ANYTHING OVERNIGHT BUT KEPT SLIGHT CHANCE ALONG THE MASON DIXON LINE AND OVER THE POTOMAC HIGHLANDS. CDFNT WILL CROSS THE AREA TOMORROW BUT IT WILL SLOW DOWN. IT APPEARS STORMS COULD FIRE OVER SRN MD TUE AFTERNOON. SPC HAS THIS AREA HIGHLIGHTED UNDER SLIGHT RISK OF SVR STORMS.
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&& .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE WILL MOVE INTO THE CENTRAL APPALACHIANS TUESDAY NIGHT AND SHIFT SLOWLY EAST FROM THERE...REACHING THE DC METRO THURSDAY MORNING. TEMPERATURES WEDNESDAY WILL BE A FEW DEGREES COOLER AND DEW POINTS WILL DROP INTO THE UPPER 50S IN MANY AREAS. SUNSHINE WILL ALSO PREDOMINATE WEDNESDAY...BUT AN APPROACHING WAVE OF LOW PRESSURE TO THE WEST WILL CAUSE CLOUDS TO INCREASE BY THURSDAY MORNING. AS THIS WAVE APPROACHES DURING THE DAY THURSDAY...RAIN SHOWERS AND POSSIBLY SOME THUNDERSTORMS WILL BEGIN TO ENCROACH FROM WEST TO EAST. CLOUDS WILL TEND TO KEEP TEMPERATURES SLIGHTLY COOLER ON THURSDAY BUT DEW POINTS WILL RISE BACK INTO THE MIDDLE 60S IN MUCH OF THE AREA. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... MODELS ARE IN MUCH BETTER AGREEMENT IN TERMS OF THE TIMING OF A WAVE OF LOW PRESSURE THURSDAY NIGHT INTO FRIDAY...HOWEVER THE TRACK AND STRENGTH STILL DIFFERS FROM MODEL TO MODEL AND RUN TO RUN. FELT CONFIDENT ENOUGH TO GO WITH LIKELY POPS ACROSS MOST OF THE AREA THURSDAY NIGHT INTO FRIDAY IN A PSEUDO WARM AIR ADVECTION PATTERN. CONVECTIVE POTENTIAL WILL DEPEND ON IF THE LOW PRESSURE AREA PASSES NORTH OR SOUTH OF THE AREA. THE LOW WILL PASS EAST AND OUT TO SEA...LIKELY BRINGING THE FRONT WITH IT BY THE WEEKEND. HIGH PRESSURE SHOULD RETURN OVER THE WEEKEND...BEFORE ANOTHER SYSTEM APPROACHES BY EARLY NEXT WEEK. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... VFR TONIGHT AND TUE. SOME STORMS COULD FIRE SOUTHEAST OF DC TUE AFTERNOON BUT ODDS SEEM LOW ATTM FOR ANY OF THE TERMINALS TO GET IMPACTED. VFR TUE NIGHT-THU MORNING ALL TERMINALS AS HIGH PRESSURE BUILDS IN. WINDS FAIRLY LIGHT. SUB-VFR LIKELY IN SHRA/ISO TSRA THU AFT-FRI AS LOW PRES MOVES ACROSS. WIND SPEED/DIRECTION FORECAST UNCERTAIN WITH LOW MOVING VERY NEAR THE AREA. VFR SHOULD RETURN ALONG W/ NWLY FLOW AROUND 10 KT SAT. && .MARINE...WINDS HAVE SUBSIDED ON THE WATERS BUT MODELS SHOW WINDS STRENGTHENING OVERNIGHT OVER THE LOWER-MID BAY DUE TO SRLY CHANNELING. MODIFIED SCA TO REMOVE MIDDLE AND UPPER POTOMAC. WINDS COULD GUST TO SCA UPPER BAY NORTH OF POOLES ISLAND TUE AFTERNOON. SCA MAY BE NEEDED FOR THAT AREA. SUB SCA WINDS WITH DRY CONDITIONS TUE NIGHT-THU MORNING UNDER HIGH PRESSURE. WIND FORECAST OVER THE WATERS IS HIGHLY UNCERTAIN THURSDAY AFT THRU FRIDAY DUE TO LOW PRESSURE PASSING VERY NEAR OR OVERHEAD. HOWEVER...SOME GUSTS IN SOUTHERLY CHANNELING ARE POSSIBLE ACROSS PORTIONS OF THE WATERS...ESPECIALLY IF THE LOW TRACK PASSES FURTHER NORTH. SHOWERS AND ISOLATED THUNDERSTORMS ARE ALSO LIKELY OVER THE WATERS THURSDAY NIGHT INTO FRIDAY. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ532>534-537- 540>543. && $$ SYNOPSIS...RCM NEAR TERM...LFR SHORT TERM...HAS/RCM LONG TERM...DFH AVIATION...RCM/LFR/DFH MARINE...RCM/LFR/DFH

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