Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 112109 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 509 PM EDT FRI APR 11 2014 .SYNOPSIS... A COLD FRONT WILL SLOWLY SAG SOUTHWARD OVER THE AREA LATER THIS EVENING...THEN SLIDING OFF THE COAST OVERNIGHT. HIGH PRESSURE WILL PARK OFF THE EASTERN SEABOARD THIS WEEKEND AND INTO EARLY NEXT WEEK...CREATING A MULTIPLE DAY FETCH OF WARMER SOUTHERLY FLOW OVER THE EASTERN SEABOARD. ANOTHER SLOW-MOVING COLD FRONT WILL ARRIVE NEXT TUESDAY...DRIFTING ACROSS THE REGION INTO THE LATE EVENING WITH MORE HIGH PRESSURE FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /THROUGH SATURDAY/...
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WIND SHIFT LN CRLY VSBL ON REFLECTIVITY DATA - AT 505 PM ON THE VERGE OF MOVG THRU BWI AND IAD. NO LTNG BEING SEEN W/ THIS SYSTEM. TEMPS DROPPING BEHIND THIS LN. AS THE COLD FRONT SAGS FARTHER SOUTH ACROSS OUR REGION TONIGHT AND EARLY SATURDAY...SLIGHTLY COOLER AIR WILL MOVE IN FROM THE NORTH. HIGH PRESSURE WILL BUILD BEHIND THE FRONT AND HEAD TOWARDS DELMARVA. NW WINDS BEHIND THE FRONT TONIGHT WILL QUICKLY BECOME NE THEN SOUTHERLY AS THE HIGH MOVES OFFSHORE AND THE PREVIOUSLY-PRONOUNCED COLD FRONT STALLS THEN RETREATS NORTHWARD AS A WARM FRONT SATURDAY. WARM TEMPERATURES EXPECTED AGAIN ON SATURDAY WITH THE SOUTHERLY FLOW. WE MAY HAVE A DRY DAY ACROSS THE REGION WITH LIMITED MOISTURE TO WORK WITH ON THE RETURN FLOW SATURDAY. HIGHS SHOULD REACH THE LOWER TO MIDDLE 70S ONCE AGAIN.
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&& .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/... A QUIET WX WEEKEND WILL STAY W/ US INTO EARLY NEXT WEEK AS HIGH PRESSURE SETTLES OFF THE ATLC COAST - THE BEST POSITION FOR ONE TO BE IN FOR WARMER WX OVER THE MID ATLC. THE WARMEST DAY OF THIS STRETCH LIKELY ON SUN...AS TEMPS ACROSS THE REGION EXPECTED TO APPROACH - IF NOT BREACH THE 80F DEG MARK...WELL BELOW ANY RECORD VALUES BUT WELL ABOVE WHAT WE`VE BEEN ACCUSTOMED TO EARLY THIS YEAR. AVG HIGHS ARE IN THE M60S FOR THIS TIME OF YEAR...SO WE`LL BE WELL ABOVE THAT BOTH SUN AND MON AFTN. DESPITE THE RELATIVELY LOW SUN ANGLE IN MID APRIL...KEEP SUNSCREEN IN MIND AND FLUIDS NEARBY IF PLANS ARE TO SPEND PART OR MUCH OF THE DAY OUTDOORS. AFTER A COOL/COLD WINTER SEASON...THE BODY MAY NOT BE SO ACCLIMATED TO SUCH WARM CONDITIONS IF OUTDOORS FOR SEVERAL HRS - SO MAKE PREPARATIONS AS IF IT WERE AN `AVERAGE SUMMER DAY`. GUSTY SLY WINDS WILL ALSO BE A PART OF THE STORY BOTH SUN AND MON AFTNS...W/ THE ENHANCED FLOW DUE TO THE RELATIVE STRENGTHS OF THE OFFSHORE HIGH AND IMPENDING STORM SYSTEM FROM THE WEST INCREASING THE PRES GRADIENT OVER THE EAST COAST. OVERNIGHT LOWS WILL ALSO BE RELATIVELY WARMER W/ L50S ON SAT NIGHT AND U50S SUN NIGHT...A GOOD 10-20F DEG ABOVE AVG. LATE MON EVE...THE NEXT LOW PRESSURE SYSTEM FROM THE WEST WILL BE INCHING ITS WAY TOWARD THE APCLNS AND EVENTUALLY ACROSS THE REGION LATE MON INTO TUE. THE 12Z GFS A BIT FASTER IN TERMS OF PRECIP ONSET...BUT FAIRLY CLOSE TO THE LATEST EURO W/ SOME SCATTERED SHOWERS DRIFTING TOWARD THE AREA LATE MON EVE BUT STAYING MAINLY OVER THE WRN HALF OF CWA - MORE COVERAGE INTO EARLY TUE MRNG FURTHER EAST. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... COLD FRONT AND ASSCD PCPN CRSG AREA TUES INTO WED MRNG. BEST CHC OF PCPN OCCURRING IS TUES MRNG AND AFTN. ACCORDING TO GFS...VORT TRAINING ACRS AREA TUES THRU WED AFTN. WK VORT MAX DUE FRI. LATE SEASON CD AIR MVS INTO REG LT TUE NGT AND WED. ALTHOUGH NOT LKLY...CANNOT RULE OUT THE PSBLTY OF PCPN BRFLY MXG IN OR CHG TO SN IN HIER ELEVS ALG ALLEGHENY FNT BEFORE ENDING. TEMPS 10-15 DEG BLO NORM FOR MID OF NXT WK. && .AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
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WIND SHIFT ABT TO BE XPRNCD AT IAD AND BWI/MTN. IN ABT AN HR AT DCA. VFR CONDITIONS OVERNIGHT AND SATURDAY WITH CIGS GENERALLY 5000 FEET OR MORE. THERE MAY BE SOME LOW LEVEL STRATUS EARLY SATURDAY. HIGH PRESSURE FROM SUNDAY INTO MON...KEEPING THE SKIES GENERALLY CLEAR BUT INCREASING WINDS OUT OF THE SOUTH AT THE SFC EACH AFTN. GUSTY WINDS IN THE 15-25KT RANGE DURING THE DAYTIME HRS...THEN DROPPING OFF EACH NIGHT. A COLD FRONT WILL SWING THRU THE AREA BY LATE TUE...BUT FAIRLY SLOWLY W/ A BULK OF THE PRECIP AFFECTING THE AREA WELL AHEAD OF AND ALONG THE BOUNDARY. WIDESPREAD RAIN SHOWERS COULD ENCOMPASS THE REGION FROM EARLY TUE INTO THE OVERNIGHT HRS - ENDING EARLY WED.
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&& .MARINE... SMALL CRAFT ADVISORIES REMAIN IN EFFECT THROUGH 11PM THIS EVENING FOR GUSTY SOUTHWEST WINDS. CAN`T RULE OUT GUSTS OVER 20 KNOTS OVERNIGHT WITH WINDS SHIFTING TO THE NORTHWEST THEN NORTHEAST AS THE FRONT PUSHES TO OUR SOUTH. SOUTHERLY CHANNELING AND LOW-MED RANGE SCA WINDS BOTH SUN AND MON AFTNS...AS A LARGE AREA OF HIGH PRESSURE HOVERS OFF THE ATLC COAST BUT INCREASES THE SFC PRES GRADIENT AS A STORM SYSTEM APPROACHES FROM THE WEST. ANOTHER SLOW-MOVING COLD FRONT WILL THEN DRIFT OVER THE WATERS BY LATE TUE...W/ PERIODS OF RAIN SHOWER ACTIVITY THROUGHOUT THE DAY BEFORE THE FRONT. HIGH PRESSURE EXPECTED TO PUSH IN FOR MID NEXT WEEK. && .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ530>543.
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&& $$ UPDATE...WOODY! PRVS...KLW/GMS/CEM

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