Area Forecast Discussion
Issued by NWS Blacksburg, VA

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRNK 151424 AFDRNK AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 1024 AM EDT MON SEP 15 2014 .SYNOPSIS... HIGH PRESSURE OVER THE AREA THIS MORNING WILL SHIFT EAST AND OFFSHORE THIS AFTERNOON BRINGING WARMER TEMPERATURES AS LIGHT RETURN SOUTHWEST FLOW DEVELOPS. THE NEXT COLD FRONT MOVES THROUGH LATER TONIGHT RESULTING IN A FEW SHOWERS FOLLOWED BY DRIER AND COOLER WEATHER INTO MID WEEK. STRONG HIGH PRESSURE WILL BUILD NORTH OF THE AREA FOR THE REST OF THE WEEK KEEPING RATHER COOL BUT OVERALL DRY WEATHER IN PLACE. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 1020 AM EDT MONDAY... FORECAST FOR TODAY REMAINS BASICALLY UNCHANGED AS WEAK HIGH PRESSURE ALONG THE MID-ATLANTIC COAST PROVIDES LIGHT SOUTHEAST FLOW INTO OUR AREA WITH PARTLY CLOUDY SKIES AND SEASONABLE TEMPS EXPECTED. LEFT CHANCE OR SLIGHT CHANCE POPS WITH A CHANCE OF ISOLATED THUNDER MAINLY ALONG THE BLUE RIDGE THIS AFTERNOON DUE TO UPSLOPE AND SOME WEAK INSTABILITY. PREVIOUS VALID DISCUSSION... AS OF 230 AM EDT MONDAY... WEAK FRONT ZIPS ACROSS FROM THE NW THIS EVENING WITH THE AREA AGAIN BASICALLY IN BETWEEN DEEPER MOISTURE WITH THE RESIDUAL BOUNDARY TO THE SOUTH AND LIMITED LIFT WITH THE UPSTREAM FRONT. GIVEN AN OVERALL WESTERLY TRAJECTORY...DOUBTING MUCH IN THE WAY OF OVERALL SHOWER COVERAGE AFTER EARLY THIS EVENING WITH PERHAPS THE WESTERN SLOPES HAVING THE BEST SHOT LATE AS UPSLOPE INCREASES. THUS THINKING OF GOING FOR JUST ISOLATED COVERAGE AFTER SUNSET AND BETTER CHANCES FAR NW AFTER MIDNIGHT WITH LITTLE POP ELSW LATE BEHIND THE FRONT. LOWS 50S WEST TO LOW 60S EAST AS A NEW ROUND OF COOL ADVECTION STARTS TO ARRIVE LATE.
-- End Changed Discussion --
&& .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 315 AM EDT MONDAY... A COLD FRONT WILL HEAD SOUTH OF THE REGION DURING THE DAY TUESDAY. FORECAST 850 MB NORTHWEST WINDS BEHIND THE FRONT SHOULD YIELD SURFACE GUSTS OF 15 TO 20 MPH ACROSS THE MOUNTAINS DURING THE MORNING HOURS. ALSO...ENOUGH RESIDUAL MOISTURE AND UPSLOPE FLOW WILL HELP MAINTAIN SOME ISOLATED SHOWERS ACROSS PARTS OF SOUTHEAST WEST VIRGINIA...NEIGHBORING COUNTIES OF SOUTHWEST VIRGINIA...AND THE NORTHERN MOUNTAINS OF NORTH CAROLINA PRIMARILY DURING THE MORNING AS WELL. TUESDAY NIGHT THROUGH THURSDAY NIGHT...A BROAD UPPER TROUGH IS FORECAST TO BECOME POSITIONED ACROSS THE U.S. EAST COAST. SURFACE HIGH PRESSURE WILL BUILD OVER PENNSYLVANIA...AND AN ASSOCIATED LEE SIDE TROUGH WILL EXTEND SOUTH THROUGH OUR REGION. WHILE THE FORECAST WILL BE A DRY ONE FOR MUCH OF THE REGION...LOW LEVEL FLOW WILL GRADUALLY TAKE ON PRIMARILY AN E-SE COMPONENT WHICH WILL POOL MOISTURE INTO THE CREST OF THE BLUE RIDGE...ALLOWING FOR THE POTENTIAL FOR SOME UPSLOPE LIGHT RAIN SHOWERS IN THE NORTHERN MOUNTAINS AND FOOTHILLS OF NORTH CAROLINA AND NEIGHBORING PARTS OF SOUTHWEST VIRGINIA. THIS E-SE FETCH MAXIMIZES...AND POTENTIALLY TAPS SOME ATLANTIC MOISTURE ON THURSDAY AND THURSDAY NIGHT. THIS WOULD ALLOW FOR A BIT MORE OF THE REGION...ESPECIALLY ALONG AND NEAR THE CREST OF THE BLUE RIDGE...TO EXPERIENCE SOME ISOLATED SHOWERS. CANNOT RULE OUT SOME ISOLATED THUNDERSTORMS BOTH TUESDAY AFTERNOON AND WEDNESDAY AFTERNOON IN THE NC MOUNTAINS. TEMPERATURES WILL TREND COOLER DURING THIS PORTION OF THE FORECAST BEHIND THE COLD FRONT PASSAGE AND AS DRIER DEW POINT AIR SETTLES INTO THE REGION. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 345 PM EDT SUNDAY... FOR MOST OF THE LONG TERM PERIOD A BROAD UPPER TROF WILL CONTINUE TO HOLD OVER THE EASTERN U.S. WITH SFC HIGH PRESSURE EXTENDING FROM THE NORTHEAST THROUGH THE MID-ATLANTIC...KEEPING A WEDGE IN PLACE THROUGH THE PERIOD. A REINFORCING SHOT OF DRIER AIR ARRIVES BY FRIDAY AS A NORTHERN STREAM WAVE BRIEFLY AMPLIFIES THE UPPER TROF. ECMWF/GFS ENSEMBLE MEANS AND DETERMINISTIC RUNS NOW SHOW AN UPPER RIDGE TRYING TO BUILD LATE IN THE LONG TERM PERIOD (SATURDAY/SUNDAY) WHICH WILL WEAKEN THE WEDGE OF HIGH PRESSURE AT THE SFC AND ALLOW TEMPS TO MODERATE. UNTIL THEN...TEMPS WILL BE BELOW NORMAL AND MORNING LOWS IN THE 40S WILL BE COMMON FOR MANY MOUNTAIN VALLEY LOCATIONS. OUTSIDE OF UPSLOPE SHOWERS IN THE SOUTHERN BLUE RIDGE/NW NC MOUNTAINS AND FOOTHILLS...MOST AREAS SHOULD REMAIN DRY. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... AS OF 700 AM EDT MONDAY... AREAS OF IFR/LIFR IN FOG/STRATUS WILL PERSIST IN SPOTS ESPCLY ACROSS THE SE WVA LOCATIONS INTO MID MORNING. MVFR CIGS ALONG WITH SPOTTY MVFR VSBYS WILL ALSO FILL BACK IN ALONG THE BLUE RIDGE EARLY THIS MORNING BEFORE HEATING AND MIXING STARTS TO LIFT CIGS AND SCOUR OUT ANY LEFTOVER FOG. ONCE THE FOG AND STRATUS LIFT...PERHAPS NOT UNTIL MIDDAY IN SPOTS...CEILINGS AND VISIBILITIES WILL IMPROVE AS THE FLOW TURNS MORE SW. EXPECT MOST TO PUSH INTO VFR DURING THE AFTERNOON WITH CU BASES BETWEEN 4-5K FT WHILE ANY SHRA LOOKS TOO ISOLATED TO INCLUDE FOR NOW. WEAK COLD FRONT SLIDES THROUGH MONDAY EVENING WITH AGAIN MOSTLY ISOLATED SHOWERS BUT LIKELY ENOUGH WESTERLY FLOW TO KEEP THINGS MOSTLY VFR DURING THE EVENING. POTENTIAL FOR LOWER CIGS TO DEVELOP...MAINLY KBLF/KLWB...LOOKS TO COME LATER TONIGHT WITH INCREASING UPSLOPE FLOW AND PERHAPS A FEW MORE SHOWERS AROUND. SOME POTENTIAL TO ALSO SEE FOG REDEVELOP ACROSS THE EAST AS WELL DESPITE THE FRONTAL PASSAGE GIVEN LIGHT WINDS AND LINGERING MOISTURE SO INCLUDED A LATE NIGHT VSBY REDUCTION OUT EAST EXCLUDING KROA OTRW SHOULD REMAIN VFR OUTSIDE OF FOG. EXTENDED AVIATION DISCUSSION... UPSLOPE MOISTURE MAY PERSIST INTO TUESDAY ALONG THE WESTERN SLOPES WHILE EXPECT BRIEF DOWNSLOPE TO BRING MAINLY VFR ELSW INTO TUESDAY AFTERNOON AS WEAK HIGH PRESSURE BUILDS IN. BROAD UPPER TROUGH REMAINS IN PLACE ACROSS THE EASTERN STATES FOR THE REMAINDER OF THE WEEK ALLOWING A LARGE AREA OF HIGH PRESSURE TO BUILD SOUTH FROM THE GREAT LAKES FOR MID WEEK BEFORE WEDGING IN FROM OFF THE MID ATLANTIC COAST BY THE WEEKEND. THIS SHOULD PUSH THE PESKY DEEP MOISTURE FURTHER SOUTH AWAY FROM THE REGION. HOWEVER BIGGER CONCERN WILL BE WITH TRAPPED RESIDUAL LOW LEVEL MOISTURE THAT MAY KEEP SOUTHERN/WESTERN LOCATIONS STUCK IN PERIODS OF MVFR CIGS ESPCLY WEDNESDAY INTO FRIDAY AS THE LOW LEVEL EAST/SE FLOW TAKES SHAPE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...JH NEAR TERM...JH/PC SHORT TERM...DS LONG TERM...PH AVIATION...JH

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