Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 261328 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 928 AM EDT THU MAR 26 2015 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO MOVE OFF THE COAST OVERNIGHT. A WARM FRONT WILL PASS THROUGH THE AREA THURSDAY MORNING FOLLOWED BY A COLD FRONT THAT WILL MOVE THROUGH THURSDAY NIGHT. AN UPPER- LEVEL DISTURBANCE WILL PASS THROUGH THE AREA LATER FRIDAY THROUGH SATURDAY. HIGH PRESSURE WILL RETURN FOR SUNDAY AND CONTINUE INTO MONDAY. && .NEAR TERM /THROUGH TONIGHT/... HIGH PRESSURE REMAINS OFF THE COAST THIS MORNING AND A WARM FRONT IS DRAPED ACROSS WEST VIRGINIA SOUTH INTO SOUTHERN VIRGINIA BEFORE IT EXTENDS NORTHEAST INTO EXTREME SOUTHERN MARYLAND. ATLANTIC MOISTURE HAS GOTTEN WRAPPED INTO THIS SYSTEM...RESULTING IN SHOWERS AND EVEN A COUPLE THUNDERSTORMS ACROSS CENTRAL VIRGINIA INTO THE WASHINGTON METROPOLITAN AREA. THIS ACTIVITY WILL SPREAD NORTHEAST INTO THE BALTIMORE METROPOLITAN AREA LATE THIS MORNING BEFORE EVENTUALLY MOVING AWAY FROM THE AREA THIS AFTERNOON. THE WARM FRONT WILL PASS THROUGH OUR AREA LATE THIS MORNING AND EARLY AFTERNOON. THERE SHOULD BE A LULL IN PRECIPITATION FOR SEVERAL HOURS BEHIND THE WARM FRONT THIS AFTERNOON. SOUTHERLY WINDS AND SOME SUNSHINE WILL RESULT IN UNUSUALLY WARM CONDITIONS FOR THIS TIME OF YEAR. A POTENT COLD FRONT LOOKS LIKE IT WILL CROSS THE AREA BETWEEN 22 AND 04Z. HIGH RESOLUTION GUIDANCE IS COMING INTO RANGE AND ALMOST ALL SOLUTIONS DEPICT A NARROW CONVECTIVE LINE ALONG THE FRONT. HAVE MAINTAINED CHC THUNDER WORDING...AS MUCAPE APPEARS IT WILL ONLY BE AROUND 500 J/KG OR LESS. GUSTY WINDS CAN BE EXPECTED WITH THE SHOWERS...ALTHOUGH SVR LEVEL GUSTS SEEM TO BE A LOW PROBABILITY DUE TO THE LOW LEVEL WIND FIELDS. UPPER LEVEL JET STREAK INTERACTS WITH FRONT ALOFT TO PROVIDE ADDITIONAL PRECIP OVERNIGHT. AS TEMPS FALL...SNOW WILL BECOME LIKELY IN THE UPSLOPE REGIONS. NOT OUT OF THE QUESTION THERE COULD BE SOME MIX FARTHER EAST...BUT CONFIDENCE TOO LOW TO INCLUDE IN FORECAST FOR NOW. LOWS OUTSIDE OF THE MOUNTAINS GENERALLY IN UPPER 30S AND 40S. && .SHORT TERM /FRIDAY/... SHOWERS WILL EXIT EAST PORTIONS FRIDAY MORNING. MOISTURE PROFILES SUGGEST THREAT OF UPSLOPE PRECIP IN WRN MTNS WILL DIMINISH TO SMALLER CHANCES. FRIDAY WILL BE MARKED BY CAA BUT A DOWNSLOPE COMPONENT WILL ALLOW FOR GOOD MIXING AND HIGHS IN THE MID 40S TO LOWER 50S. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... STRONG COLD ADVECTION AT LOW LEVELS CONTINUES AS THE CORE OF UNSEASONABLY COLD AIR MOVES OUT OF THE GREAT LAKES REGION AND INTO THE NORTHEAST...BRUSHING THE NORTHERN MID-ATLANTIC. 850 HPA TEMPS PROGGED IN THE -9C TO -13C RANGE SATURDAY. EXAMINATION OF UPPER AIR RECORDS SHOWS ONLY ABOUT A DOZEN TIMES HAS 850 TEMPS FALLEN TO -10C OR LOWER FROM MAR 27 INTO APRIL. WITH DECENT CAA ON SATURDAY... SHOULD BE ENOUGH MOISTURE FOR STRATO-CU DECK. WHERE CLOUDS HOLD... TEMPS WILL STRUGGLE INTO THE 40S EAST OF THE BLUE RIDGE AND LOW/MID 40S EAST OF THE BLUE RIDGE. HOWEVER...IF THE DECK GETS WIPED OUT DUE TO LACK OF MOISTURE AND/OR DOWNSLOPING THEN THE RELATIVE WARMTH OF LATE MARCH SUN COULD CAUSE TEMPS TO OVERCOME CAA AND RISE A CAT OR TWO HIGHER THEN FORECAST. STILL...UNSEASONABLY COLD AND BRISK ON SATURDAY. SUN-THU...HIGH PRES MOVES OVERHEAD ON SUNDAY...CHILLY START TO THE DAY WITH TEMPS WELL BELOW NORMAL...EVEN MID/UPPER TEENS IN FAR WRN MTN AREA. BY MON...TEMPS REBOUND BACK TO TO NEAR SEASONABLE NORMS BASED UPON HPC GUIDANCE AS HIGH PRES MOVES OFF SOUTHEAST US. ANOTHER COLD FRONT WILL PASS THROUGH MON NIGHT OR EARLY TUE. SOME DIFFERENCES IN MODELS ON TIMING OF THIS FRONT. NOT MUCH MOISTURE ASSOCIATED WITH IT. WED...HIGH PRESSURE AGAIN RETURNS TO THE REGION. ON THU...MODERATION IN TEMPS CONTINUES AS RETURN SW FLOW AROUND DEPARTING HIGH USHERS IN MILD AIR ACROSS THE REGION.&& .AVIATION /08Z THURSDAY THROUGH MONDAY/... CIGS AND VSBYS WILL LOWER THIS MORNING AS A WARM FRONT MOVES THROUGH...BUT SHOULD BE MAINLY VFR. SHOWERS POSSIBLE MAINLY ALONG AND EAST OF I-95. CONDITIONS IMPROVE BY MIDDAY/EARLY AFTN BUT SOUTHERLY WINDS WILL BECOME GUSTY. A COLD FRONT SWEEPS EASTWARD DURING THE EARLY EVENING HOURS WITH WIND SHIFT TO NW. LINE OF SHOWERS AND POSSIBLE EMBEDDED TSTMS ALONG FRONT...WITH POST-FRONTAL PRECIP AND LOWERED FLIGHT CONDITIONS POSSIBLE OVERNIGHT. EXPECT IMPROVEMENT BY FRIDAY WITH NW WINDS. ON SAT...EXPECT VFR CONDITIONS...EXCEPT SOME ISOLD MVFR IN SNOW SHOWERS WITH NW WINDS 10-20 KTS. HIGH PRESSURE MOVES OVERHEAD ON SUNDAY AND CONTINUES INTO MOD...WITH VFR CONDITIONS EXPECTED. && .AVIATION /13Z THURSDAY THROUGH MONDAY/... SHOWERS WILL IMPACT THE EASTERN TERMINALS LATE THIS MORNING. IFR CONDITIONS ARE POSSIBLE DURING THIS TIME. CIGS WILL IMPROVE BEHIND A WARM FRONT THIS AFTERNOON AND SOUTHERLY WINDS WILL INCREASE WITH GUSTS AROUND 25 TO 30 KNOTS EXPECTED. A COLD FRONT WILL PASS THROUGH DURING THE EVENING HOURS WITH A WIND SHIFT TO NW. LINE OF SHOWERS AND POSSIBLE EMBEDDED TSTMS ALONG FRONT...WITH POST- FRONTAL PRECIP AND LOWERED FLIGHT CONDITIONS POSSIBLE OVERNIGHT. EXPECT IMPROVEMENT BY FRIDAY WITH NW WINDS. ON SAT...EXPECT VFR CONDITIONS...EXCEPT SOME ISOLD MVFR IN SNOW SHOWERS WITH NW WINDS 10-20 KTS. HIGH PRESSURE MOVES OVERHEAD ON SUNDAY AND CONTINUES INTO MOD...WITH VFR CONDITIONS EXPECTED. && .MARINE... LIGHT WINDS AHEAD OF A WARM FRONT THIS MORNING. EXPECT SOUTHERLY WINDS TO INCREASE 20-30 KT AS WARM FRONT PASSES THIS MORNING. SHOWERS AND PERHAPS THUNDERSTORMS ARE POSSIBLE THROUGH EARLY AFTN. COLD FRONT CROSSES THIS EVENING WITH WIND SHIFT TO NW AND MORE SHOWERS AND EMBEDDED STORMS. WINDS CONTINUE TO GUST BEHIND THE FRONT. EXTENDED SCA THROUGH UNTIL FRIDAY AFTERNOON...AS MIXING MAY CONTINUE TO ALLOW HIGHER GUSTS TO REACH THE SFC. FRI NIGHT INTO SAT EXPECT SCA CONDITIONS IN COLD ADVECTION AND NW WINDS. HIGH PRESS BUILDS OVER THE WATERS ON SUNDAY AND CONTINUES INTO MON WITH WINDS FALLING BELOW SCA LEVELS EARLY SUNDAY MORNING. && .TIDES/COASTAL FLOODING... SOUTHERLY FLOW WILL INCREASE AHEAD OF A COLD FRONT TODAY CAUSING AN RISE IN WATER LEVELS. TIDAL ANOMALIES MAY BE HIGH ENOUGH FOR MINOR FLOODING DURING THE TIDE CYCLE THIS EVENING AND OVERNIGHT. HOWEVER...CONFIDENCE IS LOW BECAUSE A WIND SHIFT TO THE NORTHWEST WILL BE TAKING PLACE AT THAT TIME AND IT IS ALSO THE LOWER OF THE TWO ASTRONOMICAL NORMS. NORTHWEST WINDS WILL CONTINUE OVERNIGHT AND FRIDAY...CAUSING ANOMALIES TO DECREASE. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT FRIDAY FOR ANZ530>543. && $$ SYNOPSIS...ADS/SMZ NEAR TERM...BJL/ADS SHORT TERM...ADS LONG TERM...SMZ AVIATION...BJL/ADS/SMZ MARINE...BJL/ADS/SMZ TIDES/COASTAL FLOODING...BJL

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