Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 151832 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 232 PM EDT MON SEP 15 2014 .SYNOPSIS...
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A COLD FRONT WILL APPROACH THE REGION THIS AFTERNOON BEFORE PASSING THROUGH TONIGHT. HIGH PRESSURE WILL RETURN FOR TUESDAY THROUGH WEDNESDAY BEFORE A REINFORCING COLD FRONT MOVES THROUGH THURSDAY. HIGH PRESSURE WILL BUILD OVERHEAD LATE IN THE WEEK.
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&& .NEAR TERM /THROUGH TUESDAY/...
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HIGH PRESSURE WILL GRADUALLY SHIFT OFFSHORE LATE THIS AFTERNOON AND A LIGHT RETURN SOUTHERLY FLOW WILL ALLOW FOR SLIGHTLY WARMER CONDITIONS COMPARED TO SUNDAY. HOWEVER...MAX TEMPS WILL STILL BE A FEW DEGREES BELOW CLIMO...RANGING FROM THE 60S IN THE MOUNTAINS TO THE MIDDLE 70S ACROSS MOST OTHER LOCATIONS. HIGH AND MID-LEVEL CLOUDS WILL INCREASE LATE THIS AFTERNOON AHEAD OF AN UPPER-LEVEL DISTURBANCE AND ITS ASSOCIATED COLD FRONT THAT WILL TRACK THROUGH THE GREAT LAKES. THE UPPER-LEVEL DISTURBANCE AND ITS ASSOCIATED COLD FRONT WILL PASS THROUGH THE REGION TONIGHT. A FEW SHOWERS CANNOT BE RULED OUT LATE TONIGHT AS THIS SYSTEM MOVES THROUGH. HOWEVER...THE DYNAMICS WITH THIS SYSTEM WILL REMAIN MOSTLY TO OUR NORTH AND THE DEEPER MOISTURE WILL BE OFF TO OUR SOUTH. THEREFORE...ANY SHOWERS THAT DO OCCUR WILL BE LIMITED IN COVERAGE AND BRIEF. PRECIPITTION AMOUNTS WILL BE LIGHT AS WELL FOR AREAS THAT DO RECEIVE A SHOWER. THE COLD FRONT WILL MOVE OFF TO OUR EAST TUESDAY AND A NORTHWEST FLOW IS EXPECTED AHEAD OF HIGH PRESSURE BUILDING IN FROM THE MIDWEST. MAX TEMPS MAY ACTUALLY BE A FEW DEGREES WARMER THAN TODAY DUE TO A DEEP MIXING LAYER AND INCREASING AMOUNTS OF SUNSHINE BEHIND THE BOUNDARY. MAX TEMPS ARE FORECAST TO REACH THE MID TO UPPER 70S ACROSS MOST LOCATIONS...BUT COOLER IN THE MOUNTAINS.
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&& .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
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HIGH PRESSURE WILL BUILD OVER NEW ENGLAND TUESDAY NIGHT THROUGH WEDNESDAY BEFORE A REINFORCING COLD FRONT PASSES THROUGH THE AREA LATE WEDNESDAY NIGHT INTO THURSDAY. THE HIGH SHOULD BE CLOSE ENOUGH TUESDAY NIGHT AND WEDNESDAY TO KEEP DRY CONDITIONS IN PLACE...DESPITE AN UPPER-LEVEL TROUGH OVERHEAD. TEMPS WILL BE A FEW DEGREES BELOW CLIMO DURING THIS TIME DUE TO THE UPPER-LEVEL TROUGH. THE REINFORCING COLD FRONT LATE WEDNESDAY NIGHT INTO THURSDAY WILL BE WEAK AND LITTLE MOISTURE WILL BE ASSOCIATED WITH IT. A STRAY SHOWER CANNOT BE RULED OUT...BUT A DRY FORECAST CONTINUES FOR NOW SINCE COVERAGE WOULD BE LIMITED AT BEST.
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&& .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
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A PIECE OF ENERGY WILL TRY TO PUSH ACROSS THE REGION THURSDAY NIGHT BUT BECAUSE OF THE LACK OF MOISTURE...WE HAVE POPS GENERALLY LESS THAN 10 PERCENT. HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE GREAT LAKES AREA LATE THURSDAY NIGHT THROUGH SATURDAY...KEEPING DRY CONDITIONS IN THE REGION. A COLD FRONT WILL APPROACH THE REGION SUNDAY AND SUNDAY NIGHT...BRINGING A SLIGHT CHANCE OF SHOWERS AND PERHAPS A THUNDERSTORM OR TWO. THE MAIN UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE THROUGH THE REGION MONDAY...KEEPING A SLIGHT CHANCE OF SHOWERS IN THE PICTURE DURING THIS PERIOD.
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&& .AVIATION /18Z MONDAY THROUGH SATURDAY/...
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A COLD FRONT WILL PASS THROUGH THE TERMINALS LATE TONIGHT INTO EARLY TUESDAY. A COUPLE SHOWERS CANNOT BE RULED OUT...BUT MOST AREAS WILL BE DRY. FOG IS POSSIBLE LATE TONIGHT INTO EARLY TUESDAY...BUT THE CLOUD COVER FROM THE COLD FRONT SHOULD KEEP IT LIMITED. HIGH PRESSURE WILL BRING MORE VFR CONDITIONS TUESDAY THROUGH TUESDAY EVENING. PATCHY BR IS POSSIBLE OVERNIGHT TUESDAY INTO EARLY WEDNESDAY. A COLD FRONT WILL PASS THROUGH THE TERMINALS LATE WEDNESDAY NIGHT INTO THURSDAY...BUT THE BOUNDARY WILL BE WEAK SO IT WILL HAVE A LIMITED IMPACT ON THE TERMINALS. HIGH PRESSURE WILL RETURN FOR FRIDAY AND SATURDAY.
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&& .MARINE...
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A COLD FRONT WILL PASS THROUGH THE WATERS LATE TONIGHT. A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WATERS BEHIND THE FRONT TUESDAY...BUT IT WILL BE MARGINAL WITH NORTH-NORTHWEST WIND GUSTS NEAR 20 KNOTS. HIGH PRESSURE WILL BUILD OVER THE WATERS TUESDAY NIGHT THROUGH WEDNESDAY BEFORE A REINFORCING COLD FRONT PASSES THROUGH LATE WEDNESDAY NIGHT INTO THURSDAY. HIGH PRESSURE WILL RETURN FOR LATE IN THE WEEK.
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&& .TIDES/COASTAL FLOODING...
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WATER LEVELS REMAIN AROUND THREE QUARTERS OF A FOOT ABOVE NORMAL THIS AFTERNOON. A SOUTHERLY WIND IS EXPECTED TO DEVELOP OVER THE WATERS LATE THIS AFTERNOON INTO TONIGHT. THIS WILL CAUSE ANOMALIES TO INCREASE TO NEAR ONE FOOT ABOVE NORMAL. A COASTAL FLOOD ADVISORY IS IN EFFECT TONIGHT FROM ANNE ARUNDEL TO ST MARYS COUNTIES ALONG THE WESTERN SHORE OF THE CHESAPEAKE BAY...PRIMARILY FOR SENSATIVE AREAS. WILL HAVE TO MONITOR ANOMALIES FOR POSSIBLE MINOR TIDAL FLOODING NEAR BALTIMORE ALONG THE WESTERN SHORE OF THE CHESAPEAKE BAY AS WELL AS WASHINGTON DC AND ALEXANDRIA ALONG THE TIDAL POTOMAC RIVER...BUT A COASTAL FLOOD ADVISORY HAS NOT BEEN ISSUED AT THIS TIME DUE TO SLIGHTLY HIGHER THRESHOLDS.
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&& .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...NONE. MD...COASTAL FLOOD ADVISORY FROM 7 PM THIS EVENING TO 1 AM EDT TUESDAY FOR MDZ014-017-018. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY FROM 9 AM TO 5 PM EDT TUESDAY FOR ANZ530>543.
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&& $$ SYNOPSIS...BJL NEAR TERM...BJL SHORT TERM...BJL LONG TERM...KLW AVIATION...BJL/KLW MARINE...BJL/KLW TIDES/COASTAL FLOODING...BJL

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