Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 270234 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 934 PM EST THU FEB 26 2015 .SYNOPSIS...
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A COLD FRONT WILL SLOWLY MOVE EAST ACROSS THE AREA OVERNIGHT. HIGH PRESSURE WILL BUILD OVERHEAD INTO SATURDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY AND ANOTHER COLD FRONT WILL PASS THROUGH THE AREA MONDAY. A WARM FRONT AND LOW PRESSURE WILL CROSS THE AREA TUESDAY AND WEDNESDAY.
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&& .NEAR TERM /THROUGH FRIDAY/...
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AS OF 02Z...WEAK COLD FRONT...DRIVEN BY UPR TROUGH OVER THE GREAT LAKES... ROUGHLY ALONG THE BLUE RIDGE. THIS COLD FRONT WILL CONTINUE TO DRIFT EAST ACROSS THE AREA OVERNIGHT WITH SHIFT TO NWLY FLOW. LIGHT TO LOCALLY MODERATE SNOW ALONG THIS FRONT HAS OCCURRED OVER THE NRN SHEN VLY. WE RECEIVED A REPORT OF A DUSTING IN BERKELEY SPRINGS (MORGAN COUNTY). THIS SNOW IS JUST REACHING THE BLUE RIDGE/SOUTH MOUNTAIN AND WILL CONTINUE TO DRIFT EAST. BEST CHANCES FOR SNOW ACCUMULATION IS OVER N-CNTRL MD...PERHAPS ACROSS BALTIMORE. EXPECTATION IS MORE FLURRIES FOR THE DC METRO. MIN TEMPS LOW TO MID 20S LATE TONIGHT BEHIND THE COLD FRONT. WENT A COUPLE DEGREES ABOVE MAV/SREF GUIDANCE DUE TO CLOUDS...MIXING....AND DEW POINTS.
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&& .SHORT TERM /FRIDAY NIGHT/... CANADIAN HIGH PRESSURE WILL BUILD TOWARD THE REGION BEHIND A DEPARTING COLD FRONT FOR FRIDAY. NORTHWEST WINDS WILL USHER IN MORE BITTERLY COLD CONDITIONS. A FEW FLURRIES CANNOT BE RULED OUT...BUT THERE SHOULD BE ENOUGH DRY AIR AND SUBSIDENCE AHEAD OF THE HIGH TO PREVENT ANY SNOW ACCUMULATION. MAX TEMPS WILL RANGE FROM THE LOWER TEENS IN THE MOUNTAINS TO THE LOWER AND MIDDLE 30S IN CENTRAL VIRGINIA. THE FORECAST LEANS TOWARD THE COLDER GUIDANCE...DESPITE A DOWNSLOPING FLOW AND SOME SUNSHINE DUE THE STRONG COLD ADVECTION THAT WILL BE TAKING PLACE. HIGH PRESSURE WILL BUILD OVERHEAD FRIDAY NIGHT. MAINLY CLEAR SKIES...LIGHT WINDS AND DRY AIR WILL ALLOW FOR RADIATIONAL COOLING. THEREFORE...FRIDAY NIGHT WILL TURN OUT QUITE COLD. LEANED TOWARD THE COLDER SIDE OF GUIDANCE DUE TO THE RADIATIONAL COOLING. MIN TEMPS WILL RANGE FROM BELOW ZERO IN THE ALLEGHENY HIGHLANDS...TO THE SINGLE DIGITS ACROSS MOST OTHER LOCATIONS...TO THE TEENS IN WASHINGTON AND BALTIMORE. && .LONG TERM /SATURDAY THROUGH THURSDAY/... CANADIAN HIGH PRESSURE WILL REMAIN OVER THE REGION SATURDAY THROUGH SATURDAY NIGHT...BRINGING DRY AND COLD CONDITIONS. HIGH PRESSURE WILL MOVE OFF THE COAST SUNDAY AND A COLD FRONT WILL APPROACH FROM THE WEST. A SOUTHERLY FLOW WILL DEVELOP AHEAD OF THE COLD FRONT...ALLOWING FOR WARM AND MOIST AIR TO OVERRUN THE SURFACE COLD AIR IN PLACE. THIS MAY TRIGGER SOME PRECIPITATION...ESPECIALLY SUNDAY AFTERNOON INTO SUNDAY NIGHT. A WINTRY MIX IS POSSIBLE DURING THIS TIME...BUT CERTAINTY REMAINS LOW. THE COLD FRONT WILL PASS THROUGH LATE SUNDAY NIGHT INTO MONDAY. HIGH PRESSURE WILL BUILD IN BEHIND THIS SYSTEM FOR LATER MONDAY AND MONDAY NIGHT...BRINGING DRY AND CHILLY CONDITIONS. LOW PRESSURE WILL LIKELY IMPACT THE AREA TUESDAY INTO WEDNESDAY. DETAILS REMAIN UNCERTAIN AT THIS TIME...BUT GIVEN THE SYNOPTIC SETUP IT APPEARS THAT WARMER AIR WILL BE DRAWN INTO THIS SYSTEM. THE STRONG SUBTROPICAL RIDGE OVER THE SOUTHEAST CONUS WILL LIKELY CAUSE THE TRACK OF THE LOW TO BE TO OUR WEST. THEREFORE...THE MAIN PTYPE WILL BE RAIN OR A WINTRY MIX CHANGING TO RAIN DEPENDING ON HOW MUCH COLD AIR REMAINS ON THE FRONT SIDE OF THE STORM. THE COLD FRONT WITH THE LOW SHOULD PASS THROUGH WEDNESDAY NIGHT AND HIGH PRESSURE WILL RETURN FOR THE LATTER PORTION OF NEXT WEEK. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/...
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CIGS LOWER REST OF TONIGHT AS A COLD FRONT DRIFTS EAST FROM THE SHENANDOAH VALLEY. NWLY FLOW UP TO 10 KT BEHIND THE FRONT. LIGHT AND VARIABLE AHEAD. LIGHT SNOW WILL CONTINUE TO DRIFT EAST...MAINLY NORTH OF DC METROS. MVFR CIGS MAY LINGER THROUGH MUCH OF FRIDAY WITH ABUNDANT LOW LEVEL MOISTURE...BUT THINK THEY WILL EVENTUALLY LIFT INTO VFR RANGE. THERE IS A CHANCE OF FLURRIES FRIDAY AFTERNOON. NW WINDS WILL RANGE FROM 10-20 KT DURING THE DAYLIGHT HOURS. HIGH PRESSURE WILL BUILD OVER THE TERMINALS FRIDAY THROUGH SATURDAY NIGHT...BRINGING VFR CONDITIONS. NORTHWEST WINDS WILL GUST AROUND 15 TO 20 KNOTS FRIDAY. A FEW FLURRIES CANNOT BE RULED OUT FRIDAY...BUT MOST OF THE TIME WILL BE DRY. A COLD FRONT WILL APPROACH THE TERMINALS SUNDAY INTO SUNDAY NIGHT. A PERIOD OF RAIN OR WINTRY PRECIPITATION IS POSSIBLE DURING THIS TIME. HIGH PRESSURE WILL RETURN FOR MONDAY...BUT LOW PRESSURE WILL LIKELY IMPACT THE TERMINALS DURING THE MIDDLE PORTION OF NEXT WEEK.
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&& .MARINE...
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LIGHT AND VARIABLE FLOW BECOMES NWLY BY SUNRISE WHEN THERE IS A CHANCE OF SNOW SHOWERS AS A COLD FRONT MOVES THROUGH. HIGH PRESSURE WILL BUILD TOWARD THE WATERS FRIDAY BEHIND A DEPARTING COLD FRONT. NORTHWEST WINDS ARE EXPECTED AND A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WATERS DURING THIS TIME. THE SMALL CRAFT ADVISORY CONTINUES FRIDAY NIGHT FOR THE MARYLAND CHESAPEAKE BAY AND LOWER TIDAL POTOMAC RIVER. HIGH PRESSURE WILL BUILD OVER THE WATERS SATURDAY INTO SATURDAY NIGHT BEFORE MOVING OFF THE COAST SUNDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE WATERS SUNDAY NIGHT AS A COLD FRONT SWINGS THROUGH. HIGH PRESSURE WILL RETURN FOR MONDAY...BUT LOW PRESSURE WILL LIKELY IMPACT THE WATERS DURING THE MIDDLE PORTION OF NEXT WEEK.
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&& .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY FROM 9 AM FRIDAY TO 6 AM EST SATURDAY FOR ANZ530>534-537-539>541-543. SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM EST FRIDAY FOR ANZ535- 536-538-542.
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&& $$ SYNOPSIS...BAJ/BJL/HTS NEAR TERM...BAJ/ADS SHORT TERM...BJL LONG TERM...BJL AVIATION...BAJ/BJL/ADS MARINE...BAJ/BJL/ADS

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