Area Forecast Discussion
Issued by NWS Blacksburg, VA

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000 FXUS61 KRNK 271114 AFDRNK AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 614 AM EST FRI FEB 27 2015 .SYNOPSIS... COLD HIGH PRESSURE WILL BUILD SLOWLY EAST INTO THE AREA TODAY AND REMAIN OVER THE REGION THROUGH SATURDAY. SUNDAY THROUGH AT LEAST THE MIDDLE OF NEXT WEEK...A SERIES OF LOW PRESSURE SYSTEMS WILL SWING FRONTAL BOUNDARIES TOWARD THE AREA RESULTING IN POTENTIAL ROUNDS OF PRECIPITATION BUT OVERALL MILDER TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM EST FRIDAY... WEAK WAVE ASSOCIATED WITH THE LEADING EDGE OF THE 85H COLD FRONT WILL CROSS THE REGION FROM THE NW THIS MORNING RESULTING IN RENEWAL OF DEEP COLD ADVECTION ACROSS THE REGION. APPEARS ENOUGH LOW LEVEL MOISTURE FOR PERHAPS A FEW BANDS OF SNOW SHOWERS/FLURRIES WESTERN HALF INTO THIS AFTERNOON OTRW MOISTURE TOO SHALLOW AND CUT BY DOWNSLOPE OUT EAST. WILL LEAVE IN SOME LOW WESTERN SLOPE POPS THIS MORNING...AND CLOUDS EARLY THIS AFTERNOON...THEN DRYING AS THE LARGE ARCTIC HIGH EDGES IN FROM THE WEST WITH CLEARING ESPCLY EAST. PATCHY DENSE FREEZING FOG ALSO LOOKS TO REMAIN AN ISSUE ACROSS THE SOUTH/EAST EARLY ON BEFORE BETTER DRYING OCCURS. HIGH TEMPS OCCUR EARLY OVER THE FAR WEST...AND THEN FALL WHILE STEADYING IN THE 20S TO LOW 30S BLUE RIDGE...WITH SOME RISES TO PERHAPS LOW 40S SE WHERE WEAKER COLD ADVECTION WILL BE OFFSET BY NW FLOW. SURFACE HIGH BUILDS EAST THROUGH THE OHIO VALLEY TONIGHT BEFORE STARTING TO WEDGE SOUTH ALONG THE EASTERN SLOPES BY MORNING. THIS SHOULD ALLOW FOR ANOTHER VERY COLD NIGHT OVER SNOW COVER BUT APPEARS JUST ENOUGH MIXING AND PERHAPS SOME HIGH/MID CLOUDS TO KEEP ALL EXCEPT THE VALLEYS FROM BOTTOMING. THUS STAYED A BIT ABOVE THE VERY COLD EC MOS AND CLOSER TO THE MAV MOS WHICH INCORPORATES A LITTLE MORE CLOUDINESS AS WELL AS A WEAK NE TRAJECTORY OUT EAST. && .SHORT TERM /SATURDAY THROUGH MONDAY/... AS OF 320 AM EST FRIDAY... COLD HIGH PRESSURE IS STILL ON SCHEDULE TO WEDGE DOWN THE EASTERN SEABOARD ON SATURDAY. THIS WILL KEEP CLOUDS AND COLD AIR LOCKED IN OVER THE REGION THROUGH THE FIRST HALF OF THE WEEKEND. WOULD NOT BE SURPRISED TO SEE SOME FINE SNOW GRAINS PRECIPITATING IN THE WEDGE EAST OF THE BLUE RIDGE BUT WILL NOT INCLUDE IN THE GRIDS AS IT WOULD ONLY BE A VERY LOW POP TRACE EVENT. SWLY FLOW ALOFT WILL THEN START TO BRING WARMER AIR OVER THE WEDGE AHEAD OF AN APPROACHING COLD FRONT ON SUNDAY. GFS AND EURO RUNS ARE CONSISTENT IN BRINGING PRECIPITATION INTO THE REGION VERY LATE SUNDAY/SUNDAY NIGHT WHILE TIMING FROM THE NAM IS MUCH FASTER. WILL PUT LESS WEIGHT ON THE NAM AND LEAN TOWARDS LATER TIMING. TEMPERATURE PROFILES INDICATE ENOUGH MODERATION SO THAT BY THE TIME MEASURABLE PRECIPITATION ARRIVES IT SHOULD BE MAINLY LIQUID FOR MOST OF THE AREA. THIS DOES NOT LOOK LIKE A SIGNIFICANT QPF EVENT AS GUIDANCE WANTS TO SPLIT THE AREA WITH THE BULK OF PRECIPITATION SLIDING TO OUR NORTH AND SOUTH. THE AREAS MOST LIKELY TO SEE PROBLEMATIC PRECIPITATION LOOK TO BE FROM THE GREENBRIER VALLEY THROUGH THE ALLEGHANY HIGHLANDS WHERE THERE MAY BE A LIGHT GLAZE OF FREEZING RAIN AND SOME LIGHT SNOW ACCUMULATION LATE SUNDAY NIGHT AND MONDAY. TEMPS SHOULD SURGE AHEAD OF THE COLD FRONTAL PASSAGE ON MONDAY WITH HIGHS IN THE 50S A GOOD BET ACROSS THE PIEDMONT AND GENERALLY LOW TO MID 40S WEST OF THE BLUE RIDGE. THE FRONT WILL PUSH THROUGH THE REGION BY THE AFTERNOON WITH SOME GUSTY NORTHWEST WINDS BEHIND IT AND UPSLOPE SNOW SHOWERS FOR THE FAR WESTERN SLOPES OF THE ALLEGHANY MOUNTAINS. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... AS OF 315 PM EST THURSDAY... SOUTHWESTERLY WINDS WILL ALLOW FOR SIGNIFICANTLY WARMER TEMPERATURES FOR MONDAY...WITH TEMPERATURES RANGING FROM THE MID 40S ACROSS SOUTHEAST WEST VIRGINIA TO THE MID 50S ACROSS THE SOUTHSIDE. A COLD FRONT WILL PASS ACROSS THE REGION DURING THE AFTERNOON...BRINGING A NORTHWESTERLY WIND SHIFT AND AN INCREASE IN RAIN SHOWER ACTIVITY ALONG THE BOUNDARY. SHOWERS WILL THEN DIMINISH IN COVERAGE DURING THE EVENING IN THE DOWNSLOPE WIND FLOW...WITH A FEW SHOWERS LINGERING ACROSS THE WESTERN SLOPES FROM WEST VIRGINIA INTO NORTHERN NORTH CAROLINA. HIGH PRESSURE WILL BUILD ACROSS THE SOUTHERN GREAT LAKES MONDAY EVENING...EVENTUALLY CROSSING TO NEW ENGLAND...WHERE IT WILL THEN BUILD SOUTHWARD ACROSS THE MID ATLANTIC BY TUESDAY MORNING. ANOTHER DEEPER LOW PRESSURE SYSTEM WILL DEVELOP OVER THE PLAINS ON TUESDAY...AND PUSH RAPIDLY NORTHEAST TOWARD THE GREAT LAKES. COLD SURFACE TEMPERATURES PROVIDED BY HIGH PRESSURE COMBINED WITH THE WARM AIR ALOFT AND DEEP MOISTURE AS PROVIDED BY THE LOW PRESSURE SYSTEM TO OUR WEST WOULD MAKE FOR A CHANCE FOR FREEZING RAIN FROM THE INTERSTATE 64 CORRIDOR...POSSIBLY AS FAR SOUTH AS THE NEW RIVER VALLEY. THE LOW PRESSURE SYSTEM WILL DRAG A COLD FRONT ACROSS OUR AREA ON WEDNESDAY...POTENTIALLY BRINGING A ROUND OF LOCALLY HEAVY RAIN TO THE MOUNTAINS. CHILLY ARCTIC AIR WILL BUILD INTO THE REGION BEHIND THE COLD FRONT. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/...
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AS OF 600 AM EST FRIDAY... FREEZING FOG/STRATUS THE MAIN ISSUES ACROSS THE EAST THIS MORNING WHERE LOOKING AT LIFR/IFR AT TIMES AT KDAN/KLYH AND EXPECT THIS TO PERSIST UNTIL MIXING/DRYING ARRIVES BY MID MORNING. OTHERWISE WAVE AXIS ALONG THE LEADING EDGE OF THE MUCH COLDER AIR ALOFT CROSSING THE WEST THIS MORNING WILL CONTINUE TO RESULT IN SCATTERED FLURRIES AND SNOW SHOWERS MAINLY FROM KBCB WEST. THIS WILL ALSO ALLOW FOR MVFR TO LOW END VFR CIGS TO PREVAIL FROM THE BLUE RIDGE WEST ALONG WITH OCNL MVFR VSBYS...WITH MAINLY SCATTERED LOW CLOUDS OUT EAST INTO MIDDAY. MVFR CIGS SHOULD FINALLY ERODE OVER THE MOUNTAINS DURING THE AFTERNOON BUT HOW FAST REMAINS LOW CONFIDENCE AT THIS POINT. WINDS TURN NORTHWEST BEHIND THE FRONT AT 10-15 KTS OVER THE MOUNTAINS AND 5-10 KTS ACROSS THE PIEDMONT. LATEST BUFKIT MODEL SOUNDINGS SUGGEST SOME INFILTRATION OF HIGH/MID CLOUDS OVERNIGHT AS WELL AS PERHAPS SOME LOW CLOUDS IN A STRIP FROM KLYH TO KDAN WHERE WILL INCLUDE SOME LOWER VFR CIGS LATE. SOME PATCHY FREEZING FOG ALSO AGAIN POSSIBLE ACROSS THE EASTERN LOCATIONS LATE TONIGHT BUT GIVEN DRYNESS UNDER STRONG HIGH PRESSURE WILL LEAVE OUT OF THE TAFS FOR NOW. VFR COLD HIGH PRESSURE WILL PREVAIL ON SATURDAY. SUNDAY INTO MONDAY...OUR NEXT WEATHER SYSTEM WILL MOVE THROUGH THE AREA. CONFIDENCE IS LOW CONCERNING THE EXACT DETAILS ON TIMING AND PRECIP TYPE. HOWEVER...IT IS PROBABLE THAT THIS TIME PERIOD WILL BE ONE WITH SUB-VFR CONDITIONS FOR MANY PARTS OF THE AREA. ON THE HEELS OF THE SUNDAY/MONDAY SYSTEM WILL BE YET ANOTHER POTENTIALLY POTENT SYSTEM THAT MAY IMPACT ALL OR PARTS OF THE REGION LATE MONDAY NIGHT INTO AND THROUGH TUESDAY.
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&& .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NCZ001>006- 018>020. WV...NONE. && $$ SYNOPSIS...DS/JH NEAR TERM...JH SHORT TERM...MBS LONG TERM...MBS/NF AVIATION...DS/JH/NF/WP

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