Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 100728 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 328 AM EDT THU APR 10 2014 .SYNOPSIS...
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HIGH PRESSURE WILL MOVE OFF THE COAST TODAY. A COLD FRONT WILL STALL OUT OVER THE AREA FRIDAY AND A WAVE OF LOW PRESSURE WILL RIDE ALONG THE BOUNDARY...PASSING THROUGH OUR AREA FRIDAY NIGHT. HIGH PRESSURE WILL RETURN FOR SATURDAY BEFORE MOVING OFF THE COAST EARLY NEXT WEEK.
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&& .NEAR TERM /THROUGH FRIDAY/...
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HIGH PRESSURE WILL MOVE OFF THE COAST TODAY AND A RETURN FLOW FROM THE SOUTHWEST WILL DEVELOP. THE SOUTHWEST WIND WILL COMBINE WITH PLENTY OF SUNSHINE TO USHER IN WARMER TEMPERATURES. IT WILL BE BREEZY DURING THE AFTERNOON DUE TO A DEEP MIXING LAYER AND TIGHTENING PRESSURE GRADIENT BETWEEN HIGH PRESSURE OFF THE COAST AND A COLD FRONT MOVING INTO THE OHIO VALLEY. SOUTHWEST WINDS WILL GUST AROUND 20 TO 30 MPH THIS AFTERNOON. MAX TEMPS WILL RANGE FROM THE 50S IN THE MOUNTAINS TO THE LOWER AND MID 70S IN THE WASHINGTON METROPOLITAN AREA AS WELL AS CENTRAL VIRGINIA. A BAY BREEZE WILL KEEP TEMPS A BIT COOLER ALONG THE WESTERN SHORE...WITH MAX TEMPS GENERALLY IN THE 60S. A SOUTHWEST 50 KT LOW LEVEL JET DEVELOPS OVERHEAD TONIGHT AHEAD OF THE COLD FRONT ASSOCIATED WITH UPPER LOW PRESSURE OVER THE HUDSON BAY. THIS FRONT LOSES MOMENTUM AND STALLS OVER THE REGION FRIDAY. SOME INSTABILITY IS PRESENT BOTH NORTH OF THE SURFACE FRONT ACROSS E WV/NORTHERN MD AND SOUTH OF THE SURFACE FRONT WHERE MLCAPES OF A COUPLE HUNDRED J/KG ARE PRESENT FRIDAY AFTERNOON. HAVE INTRODUCED A SCHC OF THUNDER ACCORDINGLY.
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&& .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
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A SHORTWAVE TROUGH WILL MOVE INTO QUEBEC FRIDAY EVENING AND LOW PRESSURE WILL BE ALONG A STALLED COLD FRONT ACROSS THE MID ATLANTIC. MID LEVEL FORCING WILL BE COUPLED WITH THE TAIL END OF THE JET STREAK AND SHOWERS WILL BE POSSIBLE INTO FRIDAY EVENING. MENTIONED ISOLATED THUNDERSTORMS FOR THE CENTRAL FOOTHILLS AND SRN MD WHICH ARE ON THE SOUTH MORE UNSTABLE SIDE OF THE LOW. FCST SOUNDINGS HAVE SKINNY CAPE AND UNIDIRECTIONAL SHEAR COUPLED WITH NO SFC HEATING WILL LIKELY LEAD TO MORE SHOWERS AS THE LOW MOVES EASTWARD. THE WEAK FRONT WILL BE ABSORBED BY THE HIGH IN THE ATLANTIC AND WINDS WILL BECOME SOUTHERLY INTO SATURDAY. TEMPS WILL BE CLOSE TO 70 SAT AND APPROACHING THE UPPER 70S SUN. A DISTURBANCE WILL CROSS THE REGION SUNDAY AND A FEW SHOWERS MAY MOVE INTO THE NRN REACHES OF THE CWA SUN AFTERNOON.
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&& .LONG TERM /MONDAY THROUGH WEDNESDAY/...
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HIGH PRESSURE OVER THE ATLANTIC WILL CONTINUE TO USHER IN WARM AND HUMID CONDITIONS MONDAY. LOW PRESSURE IS EXPECTED TO APPROACH THE GREAT LAKES BY MONDAY TRAILING A COLD FRONT. 00Z ECMWF IS SLOWER THAN THE GFS BUT BOTH MODELS HAVE MOISTURE STREAMING INTO THE AREA MONDAY NIGHT AND TUESDAY. HEAVY RAIN ARE LIKELY ACROSS THE REGION MONDAY NIGHT INTO TUESDAY. COLD AIR ADVECTION BEHIND THE FRONT WILL LOWER TEMPERATURES INTO THE 50S BY THE MIDDLE OF NEXT WEEK.
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&& .AVIATION /08Z THURSDAY THROUGH MONDAY/...
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VFR CONDITIONS ARE EXPECTED THROUGH TODAY ACROSS THE TERMINALS. WINDS WILL SHIFTING TO THE SOUTHWEST AND GUST TO AROUND 20 TO 25 KNOTS THIS AFTERNOON. AREAS OF MVFR RESTRICTIONS MAY BE PRESENT FRIDAY DUE TO SHOWERS AND POSSIBLE ISOLATED TSTMS ALONG A SLOW MOVING COLD FRONT. A COLD FRONT WILL CROSS THE REGION MONDAY THROUGH TUESDAY NEXT WEEK AND HEAVY RAIN IS EXPECTED AT THAT TIME.
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&& .MARINE...
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HIGH PRES WILL MOVE OFF THE COAST TODAY AND A RETURN FLOW FROM THE SOUTH WILL DEVELOP. A DEEP MIXING LAYER AND TIGHTENING PRESSURE GRADIENT WILL CAUSE THE POTENTIAL FOR GUSTY WINDS AROUND 20 TO 25 KNOTS. A SMALL CRAFT ADVISORY IS IN EFFECT THIS AFTERNOON FOR THE NORTHERN PORTION OF THE MARYLAND CHESAPEAKE BAY AND THE UPPER TIDAL POTOMAC RIVER. FARTHER SOUTH...THE GRADIENT MAY NOT BE AS STRONG AND THE RELATIVELY COOLER WATERS MAY PREVENT THE DEEP MIXING LAYER FROM DEVELOPING. THEREFORE...WINDS HAVE BEEN CAPPED AROUND 15 KNOTS FOR NOW. SCA CONDITIONS ARE EXPECTED WITH SOUTHWEST WINDS TONIGHT AHEAD OF AN APPROACHING COLD FRONT. SCA CONDITIONS WILL BE MET AGAIN AS WINDS INCREASE. SOUTHERLY FLOW WILL PERSIST ACROSS THE WATERS SATURDAY THROUGH MONDAY. A COLD FRONT WILL CROSS THE WATERS TUESDAY AND SOUTHERLY WINDS WILL INCREASE MONDAY. A SCA WILL BE POSSIBLE MONDAY THROUGH WEDNESDAY 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 NOON TODAY TO 6 AM EDT FRIDAY FOR ANZ530>532-538>540. SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT FRIDAY FOR ANZ533-534-537-541>543. SMALL CRAFT ADVISORY FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR ANZ535-536.
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&& $$ SYNOPSIS...SDG NEAR TERM...SDG SHORT TERM...HAS LONG TERM...HAS AVIATION...SDG/HAS MARINE...SDG/HAS

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