Area Forecast Discussion
Issued by NWS Blacksburg, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 210215 AFDRNK AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 1015 PM EDT SAT SEP 20 2014 .SYNOPSIS... HIGH PRESSURE TO OUR NORTH WILL SLIDE EAST TONIGHT AS LOW PRESSURE OFF THE SOUTHEAST COAST LIFTS NORTH TO JUST OFF THE NORTH CAROLINA COAST BY SUNDAY MORNING. A COLD FRONT WILL MOVE EAST ACROSS OUR REGION SUNDAY INTO SUNDAY NIGHT AS LOW PRESSURE MOVES UP THE ATLANTIC OCEAN. MONDAY THROUGH THURSDAY...A LARGE HIGH PRESSURE SYSTEM WILL COVER MUCH OF THE EASTERN UNITED STATES. && .NEAR TERM /THROUGH SUNDAY/... AS OF 1015 PM EDT SATURDAY... FORECAST ON TRACK. HIGH CLOUDS STREAMING NORTH ASSOCIATED WITH LOW PRESSURE ALONG THE SOUTHEAST ATLANTIC COAST. GSO EVENING SOUNDING INDICATED THIS CLOUD LAYER WAS BETWEEN 35-40KFT AGL OR 200-260 MB. MODELS KEEP THIS MOISTURE PINNED MAINLY TO COAST JUST BRUSHING OUR EASTERN CWA...WITH LYH/MTV/GSO AND POINTS EAST BECOMING OVC AT TIMES OVERNIGHT FROM THIS HIGHER LAYER OF CLOUD. LOOKING WEST... CLOUDS WERE ALSO APPROACHING FROM THE OHIO VALLEY...THIS CLOUD COVER WAS ASSOCIATED WITH AN UPPER TROUGH OVER THE GREAT LAKES. THE UPPER TROUGH OVR THE GREAT LAKES REGION WILL DEEPEN AND TRAVEL EAST TOWARD NEW ENGLAND ON SUNDAY. SFC HIGH PRESSURE WILL SLIDE EAST TONIGHT...AS LOW PRESSURE OF THE GEORGIA COAST LIFTS NORTHWARD IN THE ATLANTIC OCEAN. HIGH LEVEL CLOUDS WILL SPREAD NORTHWARD AHEAD OF THE SOUTHEAST LOW CENTER TONIGHT. ADDED THE MENTION OF PATCHY FOG OVERNIGHT. WENT WITH LOW TEMPERATURES CLOSE TO THE ADJMAVBC WITH READINGS FROM THE LOWER 50S IN THE COOLER VALLEYS TO NEAR 60 IN THE PIEDMONT. A COLD FRONT WILL MOVE ACROSS THE REGION SUNDAY INTO SUNDAY NIGHT. THIS STRONG FRONTAL BOUNDARY WILL BE PUSHED BY AN UPPER LEVEL TROUGH TRACKING OVER THE GREAT LAKES. THE FRONT AND ASSOCIATED CONVECTION IS EXPECTED TO APPROACH THE AREA SUNDAY AFTERNOON...TRAVEL ACROSS THE MOUNTAINS SUNDAY EVENING AND EXIT THE PIEDMONT SUNDAY NIGHT. WITH THE STRONG MIDLEVEL FLOW AT 700 MB AS THE UPPER TROUGH DEEPEN AND SOME INSTABILITY...SPC IN THE DAY 2 CONVECTIVE OUTLOOK HAS ALLOWED FOR A 5 PERCENT CHANCE OF AN ISOLATED STRONG THUNDERSTORM WITH GUSTY WINDS BEING THE MAIN THREAT FOR SUNDAY AFTERNOON. LEANED HIGH TEMPERATURES SUNDAY CLOSE TO ADJMETBC WITH VALUES FROM THE MID 70S IN THE MOUNTAINS TO THE MID 80S IN THE PIEDMONT. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... AS OF 330 PM EDT SATURDAY... THE COLD FRONT WILL ENTER OUR SOUTHEAST WEST VIRGINIA COUNTIES SHORTLY BEFORE MIDNIGHT SUNDAY EVENING...AND WILL CONTINUE RAPIDLY SOUTHEAST...EXITING THE SOUTHSIDE BY AROUND 6 AM MONDAY MORNING. THE FRONT WILL BRING WITH IT A NORTHWESTERLY WIND SHIFT THAT WILL USHER IN COOLER AND DRIER CANADIAN AIR...DEFINITELY A SIGNAL THAT AUTUMN IS COMING AS WE APPROACH THE EQUINOX. DRIER AIR WILL CAUSE A RAPID REDUCTION IN SHOWER ACTIVITY DURING THE OVERNIGHT HOURS...WITH ONLY A FEW SPRINKLES REMAINING ACROSS OUR NORTHWEST FLOW UPSLOPE REGIONS IN SOUTHEAST WEST VIRGINIA BY DAWN. HIGH PRESSURE WILL BUILD INTO THE AREA ON MONDAY ON A 4MB TO 5MB PRESSURE GRADIENT...RESULTING IN GUSTY NORTHWEST WINDS REACHING 20 MPH TO OCCASIONALLY 25 MPH AT TIMES ALONG THE HIGHER RIDGES. GUSTS ACROSS THE PIEDMONT WILL BE LOWER...GENERALLY AROUND 15 MPH. WIND SPEEDS WILL DIMINISH DURING EARLY EVENING AS THE CENTER OF HIGH PRESSURE SINKS SOUTH OF THE GREAT LAKES TOWARD THE OHIO RIVER VALLEY. HIGH PRESSURE WILL REMAIN THE DOMINANT FEATURE OF OUR WEATHER THROUGH TUESDAY NIGHT...GRADUALLY PUSHING TOWARD NEW ENGLAND TO BRING OUR WINDS INCREASINGLY NORTHEASTERLY. WITH CLEAR SKIES EXPECTED MONDAY THROUGH TUESDAY NIGHT...AFTERNOON HIGHS WILL RANGE FROM THE MID 60S ACROSS THE MOUNTAINS TO THE MID 70S ACROSS THE PIEDMONT. OVERNIGHT LOWS WILL FALL INTO 40S...POSSIBLY INTO THE UPPER 30S IN A FEW OF THE DEEPER MOUNTAIN VALLEYS MONDAY NIGHT. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 100 PM EDT SATURDAY... THE EXTENDED PERIOD IS DOMINATED BY A 1032MB SURFACE HIGH THAT STARTS IN SOUTHERN QUEBEC ON WEDNESDAY AND WILL SLOWLY DRIFT SOUTH OVER THE NE STATES BY SATURDAY. THE RESULT OF THIS WILL BE AN EASTERLY WEDGE FLOW THROUGH THE ENTIRE PERIOD. THERE IS SIGNIFICANT DIFFERENCES IN PLACEMENT OF A MID LEVEL CLOSED LOW BY THE GFS AND THE ECMWF TO OUR WEST...WHICH WILL IMPACT HOW MUCH MOISTURE CAN GET PULLED INTO THE REGION. AT THIS POINT TRENDED TOWARD HPC AND THE DRIER GFS SOLUTIONS AND KEPT JUST LOW CHANCE POPS ALONG AND EAST OF THE BLUE RIDGE FROM THURSDAY THROUGH THE END OF THE PERIOD. ANY PRECIP THAT DOES FALL WILL LIKELY BE JUST PATCHY DRIZZLE WITH LITTLE TO NO ACCUMULATION. WENT BELOW GUIDANCE FOR HIGH TEMPS AS THE MODELS ARE TYPICALLY TOO WARM WITH AN EASTERLY FLOW. EXPECT SURFACE HIGHS OF MID TO UPPER 60S ACROSS THE MOUNTAINS TO LOW 70S EAST OF THE BLUE RIDGE. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... AS OF 720 PM EDT SATURDAY... VFR CONDITIONS REPORTED AT ALL TAF SITES EARLY THIS EVENING...AND THESE CONDITIONS ARE EXPECTED TO CONTINUE INTO THE EARLY PART OF THE NIGHT. FOG WILL DEVELOP AGAIN LATE TONIGHT IN THE RIVER VALLEYS...IMPACTING VISIBILITIES AT KLWB AND KBCB. LIFR VISIBILITIES EXPECTED AT KLWB WITH MVFR VISIBILITIES AT KBCB. AFTER AN ENTIRE DAY OF DRYING AND SLIGHTLY LOWER DEWPOINTS COMPARED TO THIS TIME YESTERDAY...CHANCES FOR FOG AT KDAN AND KLYH ARE LOWER...AND FOG WAS NOT INCLUDED AT THESE SITES. FOG WILL DISSIPATE SUNDAY MORNING AFTER DAYBREAK....BUT MOISTURE ADVANCING AHEAD OF AN APPROACHING COLD FRONT WILL BRING MOSTLY CLOUDY SKIES...WITH LOW VFR CIGS BY LATE SUNDAY MORNING TO THE MOUNTAINS. SCATTERED SHOWERS WILL ALSO DEVELOP IN THE MOUNTAINS DURING THE AFTERNOON. LOW LEVEL WINDS INCREASE WITH THE APPROACHING FRONT...AND GUSTS 20-25KTS ARE POSSIBLE BY SUNDAY AFTERNOON IN THE HIGHEST ELEVATIONS. MEDIUM TO HIGH CONFIDENCE IN CEILINGS AND VISIBILITIES DURING THE PERIOD. EXTENDED AVIATION DISCUSSION... PASSAGE OF THE COLD FRONT WILL OCCUR SUNDAY NIGHT AND WILL BRING DRIER AIR TO THE REGION FOR EARLY NEXT WEEK PROMOTING MAINLY VFR CONDITIONS. RIVER VALLEY FOG WILL STILL BE POSSIBLE AT NIGHT. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/KK NEAR TERM...KK/PM SHORT TERM...NF LONG TERM...CF AVIATION...PH

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