Area Forecast Discussion
Issued by NWS Sterling, VA

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047 FXUS61 KLWX 011915 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 315 PM EDT SUN MAY 1 2016 .SYNOPSIS...
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A FRONT WILL REMAIN STATIONARY ACROSS THE AREA THROUGH TONIGHT THEN LIFT NORTH AS A WARM FRONT MONDAY. A COLD FRONT WILL SLOWLY MOVE THROUGH MONDAY EVENING WITH MULTIPLE SURFACE WAVES MOVING ACROSS THE AREA. ANOTHER COLD FRONT IS EXPECTED WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD TOWARD THE END OF THE WEEK.
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&& .NEAR TERM /THROUGH MONDAY/...
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A STATIONARY FRONT REMAINS DRAPED FROM WRN PA SEWD TO THE BLUE RIDGE MTNS TO THE NC/VA BORDER. T-STORMS DEVELOPING OVER OH/KY ATTM ARE EXPECTED TO TRACK EWD AROUND 30 KTS AND MAKE IT INTO THE VA/WV HIGHLANDS THIS EVENING. STORMS ARE LIKELY TO WEAKEN IN INTENSITY AS THEY CROSS THE APPALACHIANS BUT SOME COULD REMAIN STRONG AS THEY CROSS THE MTNS WHERE SBCAPE VALUES ARE IN THE 250-500 J/KG RANGE. SHOWERS EXPECTED EAST OF THE BLUE RIDGE WHERE ATMS MUCH MORE STABLE. OVERNIGHT...WE`LL SEE LOW AND MID LEVELS (850-500 MB LAYER) DRY OUT AND SUBSIDENCE WITH AREAS OF DENSE FOG LIKELY TO DEVELOP DUE TO WET GROUND AND LIGHT WINDS. MORNING FOG WILL GRADUALLY ERODE MON MORNING WITH TEMPS RISING INTO THE 70S AS WARM FRONT LIFTS INTO PA. SOME DESTABILIZATION IS LIKELY TO TAKE PLACE IN THE AFTERNOON WITH SCT SHOWERS AND T-STORMS EXPECTED. BEST INSTABILITY IS EXPECTED OVER THE SRN HALF AND EAST OF THE BLUE RIDGE WHERE CDFNT WILL NOT CLEAR THOSE AREAS UNTIL EVENING.
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&& .SHORT TERM /MONDAY NIGHT/...
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MOISTURE ADVECTION CONTINUES MON NIGHT IN SOUTHWEST FLOW AHEAD OF 700-500 MB WAVE. MULTIPLE SFC WAVES ARE EXPECTED TO CROSS THE AREA MON NIGHT ALONG SLOW MOVING BDRY TO BRING ANOTHER ROUND OF MDT PRECIP.
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&& .LONG TERM /TUESDAY THROUGH SUNDAY/...
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ANOTHER IN A SERIES OF LOW PRESSURE WAVES WILL CROSS THE AREA TUESDAY...THEN DEPART TO THE NORTHEAST TUESDAY NIGHT INTO WEDNESDAY AS A STUBBORN FRONT REMAINS DRAPED OVER THE AREA. A LARGE/COLD UPPER LOW WILL DIVE OUT OF CANADA STRAIGHT SOUTH TO OVER THE MID-ATLANTIC THURSDAY...THEN SLOWLY PIVOT OFF TO THE EAST THROUGH FRIDAY LEADING TO A CONTINUATION OF UNSETTLED WEATHER. MODELS ARE MODEST WITH INSTABILITY IN SOUNDINGS AT THIS TIME BUT COULD SEE AN INCREASING TREND GIVEN THE COLD AIR ALOFT IF FLOW TAKES ON A MORE SOUTHERLY/WARM COMPONENT IN THE LOW-LEVELS WEDNESDAY. AFTER THIS UPPER LOW LIFTS OUT...A LARGE AREA OF HIGH PRESSURE WILL BEGIN BUILDING JUST OFF THE SOUTHEAST COAST LEADING TO A STRONG WARMING TREND BEGINNING OVER THE WEEKEND.
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&& .AVIATION /19Z SUNDAY THROUGH FRIDAY/...
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CIGS IMPROVING TO MVFR NOW BUT ARE EXPECTED TO DROP AGAIN TO IFR/LIFR AS ADDITIONAL SHOWERS AND POSSIBLE T-STORMS MOVE THROUGH. AREAS OF DENSE FOG LIKELY TO DEVELOP WITH LIFR AND VLIFR VSBYS POSSIBLE. SCT T-STORMS EXPECTED TOMORROW WITH ANOTHER ROUND OF MDT RAIN MON NIGHT. SUB-VFR PSBL TUE-WED IN ANY LWR CIGS/SHWRS W/ FRONT STALLED NEARBY. WINDS GENERALLY ELY 10 KTS.
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&& .MARINE...
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WINDS GENERALLY BELOW SCA BUT GUSTY NEAR T-STORMS ESPECIALLY MON AFTERNOON MIDDLE AND LOWER PORTIONS OF POTOMAC AND CHES BAY. A WEAK PRESSURE GRADIENT WILL PREVAIL OVER THE WATERS WITH A FRONT STALLED NEARBY...LEADING TO GUSTS THAT SHOULD STAY LARGELY BELOW SMALL CRAFT ADVISORY LEVELS DURING THE MIDDLE OF THE WEEK.
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&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...DFH AVIATION...LFR/DFH MARINE...LFR/DFH

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