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 241252 AFDRNK AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 752 AM EST TUE FEB 24 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE OVER THE SOUTHERN APPALACHIANS WILL MOVE EAST AND OFF THE SOUTHEAST ATLANTIC COAST TODAY. ANOTHER AREA OF LOW PRESSURE WILL MOVE ACROSS THE SOUTHERN STATES AGAIN WEDNESDAY NIGHT. MEANWHILE...HIGH PRESSURE WILL BE CENTERED TO OUR NORTH PROVIDING AN AMPLE SUPPLY OF COLD ARCTIC AIR. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 730 AM EST TUESDAY... BASED ON RADAR TRENDS AND GROUND TRUTH REPORTS...HAVE EXPANDED THE WINTER WEATHER ADVISORY TO ENCOMPASS ALL OF OUR NORTH CAROLINA COUNTIES...AMOUNTS OF 2 TO 5 INCHES IN THE MOUNTAINS AND 1 TO 3 INCHES IN THE PIEDMONT. INVERTED TROUGH OF LOW PRESSURE OVER THE SOUTHERN APPALACHIANS THIS MORNING IS RESULTING IN LIGHT SNOW FROM EASTERN TENNESSEE INTO WESTERN NORTH CAROLINA. A PERIOD OF LIGHT SNOW MAY OCCUR AS FAR NORTH AS HIGHWAY 460 IN VIRGINIA...BUT AMOUNTS ARE EXPECTED TO BE VERY LIGHT. THE HEAVIER AMOUNTS WILL BE CONFINED TO THE NORTH CAROLINA MOUNTAINS WHERE UPWARDS OF 3 TO 5 INCHES MAY OCCUR. THE BIG LIMITATION FOR MUCH MORE THAN AN INCH OF SNOW TO OCCUR FARTHER NORTH IS THE FACT THAT VERY DRY AIR...WITH DEWPOINTS IN THE SUB-SINGLE DIGITS ARE ADVECTING INTO THE FORECAST AREA FROM THE NORTH...COURTESY OF HIGH PRESSURE CENTERED OVER PENNSYLVANIA. THIS VERY DRY AIR WILL LIKELY CAUSE MOST OF THE SNOW TO SUBLIMATE BEFORE REACHING THE GROUND ACROSS THE VIRGINIAS. CAN`T TOTALLY RULE OUT A PERIOD OF LIGHT SNOW THIS MORNING AS FAR NORTH AS BLUEFIELD...BLACKSBURG...ROANOKE...AND LYNCHBURG...WITH A DUSTING POSSIBLE...BUT THE BETTER CHANCE FOR MEASURABLE WILL BE ALONG AND SOUTH OF HIGHWAY 58...AND PRIMARILY ACROSS NORTH CAROLINA...WHERE 1 TO 3 INCHES OF SNOW IS POSSIBLE FOR THE PIEDMONT OF NC AND UPWARDS OF 3 TO 5 INCHES IN THE NORTHWEST NC MOUNTAINS. THE ACCUMULATING SNOW THAT DOES OCCUR IS EXPECTED TO END OR TAPER TO FLURRIES THIS AFTERNOON. ASIDE FROM THE LIGHT SNOW TEASE THIS MORNING...THE MAIN WEATHER FOCUS FOR THE NEXT 24 HOURS WILL BE THE COLD. WENT BLO MOS FORECAST FOR TEMPERATURES TODAY AND TONIGHT. DUE TO THE CLOUD COVER AND COLD AIR ADVECTION TODAY WILL BE HARD PRESSED FOR ANY OF THE CWA TO GET ANY HIGHER THAN THE 20S...AND WITH PARTIAL CLEARING TONIGHT...SHOULD EASILY RADIATE BACK INTO THE TEENS FOR MOST AREAS AND POSSIBLY THE SINGLE DIGITS IN THE GREENBRIER VALLEY AND HIGHLANDS OF VA IF SKIES COMPLETELY CLEAR THERE. NORTHWEST WINDS OF AT LEAST 10 MPH SHOULD CERTAINLY CREATE WIND CHILLS IN THE SINGLE DIGITS IN SPITE OF WHAT THE THERMOMETER SAYS.
-- End Changed Discussion --
&& .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 430 AM EST TUESDAY... AN INVERTED TROUGH ON WEDNESDAY WILL ADVECT MOISTURE INTO OUR REGION FROM A DISTURBANCE TRACKING ACROSS THE GULF COAST. THE SURFACE LOW WILL TRACK ACROSS THE SOUTHEAST UNITED STATES WEDNESDAY NIGHT...THEN OFF THE COAST THURSDAY. SHORT WAVES/DEFORMATION ZONE ON THE NORTHERN PERIPHERY OF THIS DISTURBANCE WILL TRACK OVER THE SOUTHERN APPALACHIANS WEDNESDAY EVENING INTO THURSDAY MORNING. THE NAM...GFS AND ECMWF KEEP QPF TO THE SOUTH OF OUR CWA THROUGH 00Z THURSDAY. AFTER 00Z THURSDAY...DIFFERENCES IN THE AMOUNTS AND NORTHERN EXTENT OF QPF ARE NOTED ON THE MODEL SOLUTIONS. USED A BLEND OF GFS AND ECMWF FOR POPS AND FEEL THAT SIGNIFICANT SNOW ACCUMULATIONS WILL BE AFTER 06Z. THE HEAVIEST SNOW WILL OCCUR TO OUR SOUTH ACROSS NORTH CAROLINA. ANOTHER TIGHT GRADIENT SNOWFALL EXPECT...BEING ON THE NORTHERN EDGE OF SNOW...TOTALS FROM ZERO IN THE NORTH TO AROUND 4 INCH POSSIBLE IN HIGHEST ELEVATIONS OF WATAGUA COUNTY. WITH IT BEING 4TH PERIOD WILL HOLD OFF ON ANY HEADLINES TO WORK OUT DETAILS ON SNOW ACCUMULATIONS. WILL ADD MENTION TO THE HWO ON SNOW POTENTIAL. THIS DISTURBANCE TRACKS EAST OF THE AREA BY THURSDAY MORNING...THEN ANOTHER COLD FRONT DROPS SOUTHEAST INTO THE AREA LATE THURSDAY AFTERNOON INTO THURSDAY NIGHT. SHORTWAVE AND MOISTURE ALONG THIS FRONTAL BOUNDARY WILL BRING LIGHT SNOW TO MAINLY MOUNTAIN COUNTIES THURSDAY AFTERNOON INTO THURSDAY NIGHT. WILL CONTINUE LIGHT POPS FOR EAST OF THE BLUE RIDGE THURSDAY NIGHT AS THE FRONT ROLLS THROUGH. SNOW ACCUMULATIONS OF 1 TO 2 INCHES POSSIBLE IN THE WEST WITH HIGHER AMOUNTS ALONG THE RIDGES TO LESS THAN HALF OF AN INCH EAST. TEMPERATURES FORECAST WILL REMAIN CHALLENGING AS LONG AS SNOWPACK REMAINS IN THE AREA. HIGH TEMPERATURES WEDNESDAY WILL RANGE FROM THE MID 20S IN THE NORTHWEST TO THE LOWER 40S IN THE PIEDMONT. LOW TEMPERATURES WEDNESDAY NIGHT WILL VARY FROM THE MID TEENS IN THE NORTHWEST TO THE UPPER 20S IN THE SOUTHEAST. HIGH TEMPERATURES THURSDAY REMAIN COLD WITH READINGS FROM THE LOWER 20S IN THE MOUNTAINS TO MID 30S IN THE PIEDMONT. BEHIND THE COLD FRONT THURSDAY NIGHT INTO FRIDAY MORNING...LOW TEMPERATURES WILL DROP INTO THE SINGLE DIGITS TO LOWER 20S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 315 PM EST SUNDAY... VERY COLD TEMPERATURES TO START THE EXTENDED PERIOD BUT TRENDING TO AT OR ABOVE NORMAL BY THE END OF THE PERIOD AS UPPER LEVEL PATTERN GOES FROM A BROAD CONUS TROF TO A SPLIT FLOW REGIME WITH THE SOUTHERN STREAM BRINGING WARMER SWLY FLOW TO OUR AREA. WHILE MODELS HAVE A DECENT CONSENSUS ON THE BROAD SCALE PATTERN THERE ARE ENOUGH DIFFERENCES IN THE DETAILS AND TIMING TO KEEP A DEGREE OF UNCERTAINTY IN OUR FORECAST FOR THE WEEKEND AND INTO THE FIRST PART OF NEXT WEEK. COLD HIGH PRESSURE AT THE SURFACE WILL BE BUILDING INTO THE AREA FRIDAY AND THEN WEDGING DOWN THE EASTERN SEABOARD THIS WEEKEND AS IT SLIDES OFF THE COAST. THERE LOOKS TO BE ENOUGH MOISTURE AROUND AND...COMBINED WITH A SERIES OF UPPER LEVEL SHORT WAVES AND SOME GENTLE UPSLOPE AS THE HIGH BUILDS IN AND WEDGES DOWN THE COASTAL PLAIN...THIS WARRANTS SLGT CHC/LOW CHC POPS FOR NUISANCE TYPE RAIN/SNOW SHOWERS INTO SATURDAY. THEN AS MOIST SWLY FLOW STARTS TO INCREASE WE WILL SEE OUR CHANCES OF PRECIPITATION INCREASE ALONG WITH OUR TEMPERATURES AS WE HEAD INTO SUNDAY. HANDLING OF EVENTS THIS WEEKEND IS WHERE MODELS HAVE SOMEWHAT DIVERGENT SOLUTIONS ESPECIALLY REGARDING PROGRESSION OF SYSTEMS AND TIMING. THUS...HAVE MEDIUM CONFIDENCE AT BEST IN POPS AND LOW CONFIDENCE IN PTYPE SUNDAY AND SUNDAY NIGHT. WILL HAVE TO AWAIT FUTURE MODEL RUNS TO BUILD A BETTER CONSENSUS BEFORE MAKING DETAILED SPECULATIONS ON WINTER WEATHER POTENTIAL. BY MONDAY...LOW PRESSURE MOVING THROUGH THE NORTHEASTERN US WILL PUSH A COLD FRONT INTO OUR REGION AND BRING A GOOD CHANCE OF RAIN AS WE START OFF NEXT WEEK. && .AVIATION /13Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
AS OF 700 AM EST TUESDAY... LIGHT SNOW IS EXPECTED FROM THE VIRGINIA...NORTH CAROLINA BORDER SOUTHWARD THIS MORNING WITH IFR VSBYS IN THE PIEDMONT...AND IFR VSBYS AND CIGS IN THE NC MOUNTAINS. THE NORTHERN EDGE OF THE SNOW WILL BE VERY CLOSE TO A BLF-BCB-ROA-LYH LINE WITH VFR TO THE NORTH AND IFR TO THE SOUTH. THREAT FOR SNOW WILL WANE THIS AFTERNOON AS THE TROUGH OF LOW PRESSURE PRODUCING THE SNOW WILL MOVE EAST AND OFF THE SOUTHEAST ATLANTIC COAST. RETURN TO MAINLY VFR CONDITIONS ARE EXPECTED FOR LATER THIS AFTERNOON AND TONIGHT. LINGERING MOISTURE ACROSS THE CAROLINAS MAY RESULT IN LINGERING LOW CIGS SOUTH OF THE VA/NC BORDER. EXTENDED AVIATION DISCUSSION... ANOTHER AREA OF LOW PRESSURE IS EXPECTED TO MOVE ACROSS THE DEEP SOUTH WEDNESDAY INTO THURSDAY. POTENTIAL FOR SUB-VFR CONDITIONS WILL EXIST ACROSS THE AREA WEDNESDAY NIGHT INTO THURSDAY. YET ANOTHER CLIPPER MAY CROSS THE AREA THURSDAY NIGHT INTO FRIDAY. WHILE LESS PROBABLE...THE WESTERN EXTENT OF A COASTAL SYSTEM COULD TEAM UP WITH THE CLIPPER AND BRING THE EASTERN PORTION OF THE FORECAST REGION A GREATER COVERAGE OF WINTRY PRECIPITATION FOR THE WEEKEND.
-- End Changed Discussion --
&& .CLIMATE... RECORDS FOR TODAY. 2/24 REC LOWYEAR ROA 71967 LYH101947 DAN101964 BCB 31968 BLF-11967 LWB 9 2009 && .RNK WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
VA...NONE. NC...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NCZ001-018. WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NCZ002>006- 019-020. WV...NONE.
-- End Changed Discussion --
&& $$ SYNOPSIS...PM NEAR TERM...PM SHORT TERM...KK LONG TERM...MBS AVIATION...AMS/PM/WP CLIMATE...CF

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