Area Forecast Discussion
Issued by NWS Blacksburg, VA

Home | 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
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/...
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.

&&

.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


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