Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 251847 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 247 PM EDT SAT OCT 25 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE REGION TODAY. A REINFORCING COLD FRONT WILL PASS THROUGH THE REGION LATE TONIGHT INTO SUNDAY BEFORE HIGH PRESSURE RETURNS FOR MONDAY. THE HIGH WILL MOVE OFF THE COAST TUESDAY AND ANOTHER COLD FRONT WILL PASS THROUGH THE AREA WEDNESDAY. && .NEAR TERM /THROUGH SUNDAY/... HIGH PRESSURE IS LOCATED ACROSS THE MID ATLANTIC THIS AFTERNOON LEADING TO DRY CONDITIONS TODAY. DISSIPATING CLOUDS HAVE BEEN APPROACHING THE ALLEGHENY FRONT IN RESPONSE TO A UPPER LEVEL JET MOVING INTO THE NORTHEASTERN US. A SURGE OF W-NW WINDS AGANIST THE MTNS MAY LEAD TO A FEW RAIN SHOWERS ALONG THE ALLEGHENY FRONT LATE TONIGHT. ELSEWHERE...THESE CLOUDS MAY REACH THE POTOMAC HIGHLANDS BEFORE DISSIPATING THIS EVENING. HIGH PRESSURE AT THE SFC HAS LED TO SW WINDS USHERING IN HIGHER DEWPTS THAN FRIDAY. THE PRESSURE GRADIENT HAS INCREASED THIS AFTERNOON AND SW WINDS HAVE INCRASED TO 15-20MPH WITH GUSTS UP TO 30MPH. THESE WINDS WILL DIMINISH THIS EVENING BUT A LIGHT BREEZE WILL KEEP TEMPS IN THE 40S OVERNIGHT. THE STRONG JET ACROSS THE GREAT LAKES REGION WILL DRIVE THE NEXT CANADIAN LOW PRESSURE SYSTEM TOWARDS THE REGION TONIGHT. MOST OF THE UPWARD LIFT AND MOISTURE OF THIS SYSTEM WILL STAY NORTH OF THE MID- ATLANTIC AND A DRY COLD FRONT WILL CROSS BY SUNDAY MORNING. THE COLD FRONT THAT IS CURRENTLY LOCATED ACROSS THE MID-WEST WILL MOVE ACROSS THE MID-ATLANTIC LATE TONIGHT. THIS WILL CAUSE WINDS TO BACK TO THE NW AGAIN AND USHER IN DRIER CONDITIONS FOR SUNDAY. DEWPTS WILL DROP INTO THE 20S IN THE VA HIGHLANDS TO THE MID TO UPPER 30S EAST OF THE BLUE RIDGE MAKING FOR A DRY DAY. NW WINDS ARE EXPECTED TO BE 10-20MPH WITH GUSTS UP TO 30 MPH DURING THE AFTERNOON. THESE CONDITIONS ARE FAVORABLE FOR THE SPREAD OF WILDFIRES. PLEASE SEE FIRE WX SECTION BELOW. ANY CLOUDS IN RESPONSE TO THE UPPER LEVEL LOW ACROSS NRN NEW ENGLAND SHOULD STAY TO THE NORTH SUNDAY LEADING TO A SUNNY DAY WITH TEMPS REACHING THE MID 60S TO NEAR 70. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... HIGH PRESSURE WILL MOVE INTO THE MID ATLANTIC SUNDAY NIGHT AND WILL PUSH THE PRESSURE GRADIENT OFF THE EAST COAST. WINDS SHOULD SUBSIDE BY MONDAY MORNING. CALM AND CLEAR CONDITIONS WILL LEAD TO RADIATIONAL COOLING OVERNIGHT. TEMPS ARE EXPECTED TO DROP INTO THE MID 30S NORTH AND WEST OF THE I-95 CORRIDOR. PATCHY FROST IS POSSIBLE ESPECIALLY IN SHELTERED VALLEYS WERE TEMPERATURES MAY REACH FREEZING. THE HIGH WILL MOVE OFF THE COAST MONDAY AND SOUTHERLY FLOW WILL USHER IN WARMER CONDITIONS. THIS WILL BE THE TREND FOR THE START OF THE WORK WEEK. SOUTHERLY FLOW CONTINUES TUESDAY AS A COLD FRONT APPROACHES FROM THE MID-WEST. MOISTURE IS LAGGING WITH ONLY LIGHT WAA ALOFT. MOSTLY SUNNY CONDITIONS ARE EXPECTED TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... STRONG SHORTWAVE/PVA CROSSING GREAT LAKES INTO QUEBEC TUESDAY NIGHT INTO WEDNESDAY. ENERGY WITH THIS SYSTEM WILL STAY WELL NORTH OF CWA. ADDITIONAL WEAKER SHORTWAVES WILL MOVE EASTWARD IN ECMWF 500MB LONGWAVE TROUGH AND AFFECT THE CWA WEDNESDAY INTO THURSDAY. ANOTHER STRONG SHORTWAVE WILL SLIDE DOWN TROUGH AND REACH THE EASTERN GULF STATES BEFORE STALLING AT WEEKS END. COLD FRONT FROM THE WEST WILL CROSS THE CWA TUESDAY NIGHT THROUGH THURSDAY. WEAK SURFACE HIGH WILL BUILD INTO CWA FRIDAY WHILE A LOW DEVELOPES OVER GEORGE IN RESPONSE TO THE SHORTWAVE. PATTERN INDICATES THAT PRECIPITATION WITH THIS SYSTEM WILL NOT AFFECT THE CWA UNTIL LATE IN THE PERIOD AND AMOUNTS WILL BE LIGHT. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... VFR CONDITIONS EXPECTED TODAY AND TONIGHT AS HIGH PRESSURE CONTROLS THE MID-ATLANTIC REGION. SW WINDS WILL BECOME W-NW OVERNIGHT AS A DRY COLD FRONT CROSSES THE TERMINALS. W-NW WINDS 15-20KTS WITH GUSTS UP TO 30 KTS EXPECTED. WINDS SHOULD SUBSIDE BY SUNSET ON SUNDAY. HIGH PRESSURE MOVES ACROSS THE REGION SUNDAY NIGHT THROUGH MONDAY. VFR CONDITIONS ARE EXPECTED. && .MARINE... SW WINDS WILL CONTINUE ON THE WATERS THIS AFTERNOON. A PRESSURE SURGE HAS MOVED INTO THE NRN MARYLAND CHESAPEAKE BAY AND GUSTS OF 20KTS HAVE BEEN OBSERVED. A SCA IS IN EFFECT THROUGH EARLY EVENING. A COLD FRONT WILL CROSS THE WATERS LATE TONIGHT AND WINDS WILL BECOME W-NW. SW WINDS AHEAD OF THE FRONT WILL INCREASE ACROSS THE LOWER TIDAL POTOMAC AND MD BAY SOUTH OF DRUM PT LATE TONIGHT. A SCA IS IN EFFECT FOR THIS AREA AND EXPANDS FOR ALL THE WATERS SUNDAY. GUSTY WINDS UP TO 28KTS ARE POSSIBLE ON THE WATERS SUNDAY AFTERNOON. A PRESSURE GRADIENT WILL MOVE OFF TO THE EAST SUNDAY NIGHT AND WINDS WILL DIMINISH BY MONDAY MORNING. HIGH PRESSURE OVER THE WATERS SUNDAY NIGHT WILL MOVE OFF THE COAST MONDAY THROUGH TUESDAY. A SOUTHERLY FLOW WILL DEVELOP DURING THIS TIME. A COLD FRONT WILL PASS THROUGH THE WATERS WEDNESDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE WATERS TUESDAY AND WEDNESDAY. HIGH PRESSURE WILL RETURN FOR LATE IN THE WEEK. && .FIRE WEATHER... A DRY COLD FRONT WILL CROSS THE MID-ATLANTIC LATE TONIGHT AND GUSTY WINDS AND DRY CONDITIONS ARE EXPECTED BEHIND IT. W-NE WINDS 10-20 MPH WITH GUSTS UP TO 30MPH AND DEWPTS ARE FCST TO DROP INTO THE 20S AND 30S ACROSS THE MID ATLANTIC. THIS WILL LEAD TO DRY CONDITIONS WITH RH VALUES AROUND 25-35% BY SUN AFTERNOON. LOW FUEL MOISTURES HAVE BEEN OBSERVED ESPECIALLY IN THE BLUE RIDGE REGION OF VA. THE COMBINATION OF GUSTY WINDS...LOW RH AND LOW FUEL MOISTURES WILL LEAD TO THE ENHANCED THREAT OF WILDFIRES SUNDAY. && .TIDES/COASTAL FLOODING... DUE TO THE WESTERLY WINDS BECOMING SWLY BY AFTERNOON...CBOFS HAS TIDAL ANOMALIES INCREASING THIS AFTERNOON. THE FCST IS FOR ANNAPOLIS TO REACH MINOR FLOOD EARLY THIS EVENING BUT ANOMALIES WOULD NEED TO REACH 0.8 FEET. AT THIS TIME ANOMALIES ARE AROUND A HALF FOOT. ANOMALIES ARE NOT EXPECTED TO INCREASE THAT QUICKLY THIS AFTERNOON AND THERFORE MINOR COASTAL FLOODING IS NOT EXPECTED. && .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ530>532-538>540. SMALL CRAFT ADVISORY FROM 9 AM SUNDAY TO 2 AM EDT MONDAY FOR ANZ530>533-539>541. SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM EDT SUNDAY FOR ANZ535- 536-538-542. SMALL CRAFT ADVISORY FROM 2 AM SUNDAY TO 2 AM EDT MONDAY FOR ANZ534-537-543.
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&& $$ SYNOPSIS...HAS NEAR TERM...HAS SHORT TERM...HAS LONG TERM...CEM AVIATION...HAS MARINE...HAS FIRE WEATHER...HAS TIDES/COASTAL FLOODING...HAS

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