Area Forecast Discussion
Issued by NWS Sterling, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KLWX 311418 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1018 AM EDT SUN AUG 31 2014 .SYNOPSIS... BERMUDA HIGH PRESSURE WILL PERSIST THROUGH TUESDAY WITH AN ACTIVE PATTERN FOR THE EASTERN SEABOARD. A WEAK COLD FRONT WILL CROSS THE AREA TUESDAY NIGHT...FOLLOWED BY HIGH PRESSURE. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
HIPRES OFF THE EAST COAST OF THE CONUS THIS MRNG. THE ERN SEABOARD W/IN WARM/HUMID S/SWLY FLOW...AHD OF A CDFNT ACRS SRN CNDA. STLT/WATER VAPOR IMGRY DEPICT A STREAM OF MSTR AHD OF THE CDFNT...EMINATING FM THE GLFMEX UP ALONG THE APLCHNS TO THE UPR OHVLY/ERN GRTLKS. PWAT W/IN THIS ZONE AOA 2 INCHES. MRNG LWX RAOB DEPICTS AN INVSN ARND H9...BUT A VERY UNSTBL ENVIRONMENT ABV THAT. DAYTIME HEATING SHUD BE ABLE TO ERODE THE INVSN...BUT WL AT LEAST HOLD THINGS IN CHECK FOR A LTL WHILE. A PIECE OF ENERGY HAS BKN OFF FM MAIN STREAM...PROVIDING SHRA TO THE PTMC HIGHLANDS. RECENT HRRR RUNS SUGGEST THIS WL MAKE IT TO THE CATOCTINS BEFORE DSPTG...LKLY A RESULT OF THE INVSN. WHILE FULL SUN TEMPS IN THE MID 90S...ADVANCING CLDCVR LKLY WL KEEP MAXT LWR THAN THAT. UPDTD TEMPS TO LTST LAMP SINCE POTL CERTAINLY THERE FOR TEMPS HIER THAN MID-UPR 80S. USING A TEMP OF 90F AND DEWPTS IN THE LWR 70S...SHUD HV 2000-2500 J/KG CAPE BY LT DAY. BUT...FORCING WL COME IN THE WAY OF PVA/MID LVL 20-30 KT FLOW...AND THAT WL HOLD OFF TIL AFTR 18Z FOR THE MTNS...AND CLSR TO 00Z FOR THE CSTL PLAIN. ALSO NEED TO BE MINDFUL OF THE DIFF HTG BNDRY...WHICH CUD BE ANTHR SOURCE OF INITIATION. CERTAINLY HV THE DOWNDRAFT POTL FOR STRONG STORMS TDA...BUT DONT THINK WE/LL BE ABLE TO ACHIEVE FULL POTL. CANNOT RULE OUT LCL WET MICROBURSTS...BUT BELIEVE THEY WL BE HIT-OR-MISS IN NATURE. AMPLE MSTR WL ALSO LEAD TO HVY RAINERS...THE OTHER THREAT THIS PM. RAFL RATES WL BE SUFFICIENT TO LEAD TO A LCL FLASH FLOOD THREAT... SPCLY UNDER TRAINING CELLS.
-- End Changed Discussion --
&& .SHORT TERM /MONDAY THROUGH TUESDAY/... AFTER THE EVE CONVECTION HAS DISSIPATED OFF AND MOVED EAST... ANOTHER REGIONAL BATCH OF LIGHT/MOD RANGE IS TAGGED BY NEAR TERM GUIDANCE AS MOVING ALONG THE MASON-DIXON LINE AS WELL - KEEPING PRECIP CHANCES ALIVE INTO EARLY MON. AS THE BACK END OF THIS FEATURE PASSES BY TO THE NORTH...PRECIP CHANCES WILL REMAIN IN THE LOW CHANCE RANGE THRU MON AFTN/EVE ACROSS THE ERN HALF OF THE CWA BUT MAINLY OF A LIGHT/SCTD NATURE...OUTSIDE OF A FEW TSTMS. THE RELATIVE LACK OF ACTIVITY AND CLEARING SKIES FROM WEST-TO-EAST WILL ALLOW TEMPS TO CLIMB BACK INTO THE U80S AND SOME L90S FOR THE AREA ON MON AFTN...W/ DEWPOINTS STANDING PAT IN THE U60S/L70S - ANOTHER MUGGY DAY FOR THE AREA. WEAK RIDGING CROSSES THE CENTRAL MID-ATLANTIC MONDAY NIGHT INTO TUESDAY...MAKING FOR A REPRIEVE IN THUNDERSTORMS FOR 12-18 HRS. WITH THE BERMUDA HIGH IN PLACE...EXPECT TUESDAY TO HAVE THE HIGHEST TEMPERATURE DAY SINCE JULY. MAX TEMPS LOW TO MID 90S ACROSS LOWER ELEVATIONS. THE NEXT COLD FRONT APPROACHES LATE TUESDAY AND CROSSES THAT NIGHT. WITH PLENTY OF ENERGY FROM THE HOT DAY...EXPECT AT LEAST ISOLATED SEVERE WEATHER...PARTICULAR FOR WRN ZONES THAT ARE PROGGED TO GET THE EVENING ACTIVITY. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... HIGH PRESSURE BUILDS IN BEHIND WITH CONTINENTAL AIR (NOT CANADIAN) SO TEMPERATURE REMAIN ABOVE NORMAL. EXPECT MAX TEMPS AROUND 90F WEDNESDAY THROUGH FRIDAY. RETURN FLOW AND ACTIVE WEATHER RETURNS LATE FRIDAY INTO THE WEEKEND. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
MRNG FLGT RESTRICTIONS HV CLRD ACRS THE TERMINALS. SCTD SHRA/TSRA XPCTD TO DVLP LATER TDA INTO THIS EVNG. LCL IFR PSBL. SCT NATURE OF THE THREAT LENDS TO VCTS IN TAF ATTM. MORE SPECIFIC RESTRICTIONS WL BE PLACED INTO FCST WHEN/WHERE APPROPRIATE. SLY WINDS WILL PERSIST INTO MON...ALONG W/ A FEW HIT/MISS SHOWERS AS WELL THRU MON EVE. BRIEF HIGH PRESSURE/VFR TUESDAY ON A HOT DAY (MAX TEMPS IN THE MID 90S). SCATTERED STRONG THUNDERSTORMS TUESDAY NIGHT AS A WEAK COLD FRONT CROSSES THE REGION. HIGH PRESSURE/VFR OUTSIDE OF POTENTIAL MORNING FOG MID TO LATE WEEK.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
SLY FLOW ACRS THE MARINE AREA SUN-MON. GUSTS TAFTN WL APPROACH SCA LIMITS. AM CONSIDERING POSTING ADVY FOR THE AFTN-EVNG. FLOW PTTN CONTS INTO MON. SUB SCA SWLY FLOW MONDAY NIGHT THROUGH TUESDAY. WEAK COLD FRONT BRINGS WLY FLOW LATE TUESDAY NIGHT THROUGH WEDNESDAY. HIGH PRESSURE OVERHEAD WEDNESDAY NIGHT AND THURSDAY.
-- End Changed Discussion --
&& .TIDES/COASTAL FLOODING...
-- Changed Discussion --
DEPARTURES ON THE UPR TIDAL POTOMAC RIVER AND MOST OF THE BAY HOVERING AROUND 1 FT. LWTV2/SLIM2 ONLY 3/4 FT ABOVE NORMAL. BASED ON CURRENT TRENDS...THE CURRENT TIDE CYCLE WILL NOT CAUSE ISSUES...ALTHOUGH ITS MIGHTY CLOSE TO ADVY AT ANNAPOLIS. WINDS WILL REMAIN SLY THRU THE DAY. THE PM TIDE IS THE HIGHER ONE ASTRONOMICALLY...SO WL NEED TO CONSIDER ADVYS. WL CONT TO MONITOR.
-- End Changed Discussion --
&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...BAJ NEAR TERM...HTS SHORT TERM...GMS LONG TERM...BAJ AVIATION...HTS/GMS/BAJ MARINE...HTS/GMS/BAJ TIDES/COASTAL FLOODING...HTS

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.