FXUS61 KRNK 301105
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
605 AM EST MON NOV 30 2009

.SYNOPSIS...
A COLD FRONT WILL DROP SOUTHEAST THROUGH THE AREA TODAY AND THEN
OFFSHORE THIS EVENING. HIGH PRESSURE SLIDES IN BEHIND THE FRONT
TONIGHT THROUGH TUESDAY NIGHT BEFORE ANOTHER STRONG LOW PRESSURE
SYSTEM ALONG THE GULF COAST BRINGS MOISTURE BACK NORTH BY
WEDNESDAY. THIS STORM SYSTEM WILL LIFT NORTH ALONG THE
APPALACHIANS WEDNESDAY INTO WEDNESDAY NIGHT FOLLOWED BY MUCH
COLDER AIR BEHIND THE TRAILING COLD FRONT FOR THE END OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
COLD FRONT NEARING THE OHIO RIVER ATTM SHOULD CONTINUE TO SLIDE SE 
CROSSING THE WEST THIS MORNING AND THE PIEDMONT BY MID OR LATE 
AFTERNOON. LOBE OF DEEP MOISTURE AND SHRA AHEAD OF THE FRONT LOOKS 
TO WORK INTO THE WESTERN SLOPE ZONES AROUND DAYBREAK BEFORE 
WEAKENING/SHIFTING EAST OF THE MOUNTAINS BY MIDDAY. DECENT RH 
TRANSPORT COMBINED WITH SOME BACKING ALOFT SHOULD PREVENT A TOTAL 
SPLIT IN SHRA UPON CROSSING THE RIDGES TODAY BUT MORE QPF FAR WEST 
AND LEAST JUST IN THE LEE OF THE BLUE RIDGE GIVEN LOW LEVEL WESTERLY 
FLOW. HOWEVER AMOUNTS OVERALL A QUARTER/HALF INCH WESTERN THIRD AND 
SE WITH LESS IN BETWEEN. OTRW KEPT OVERALL TREND WHICH KEEPS 
CAT/LIKELY POPS WEST THIS MORNING...AND THEN BRIEFLY OUT EAST DURING 
THE AFTERNOON BEFORE THE FRONT SLIDES THRU. SHOULD SEE A QUICK BREAK 
IN COVERAGE MOUNTAINS BY MID AFTERNOON ONCE THE DEEPER WESTERLY FLOW 
CLIPS OFF THE PRECIP SO TRIMMED CHANCES THERE AFTER 18-20Z. TEMPS 
TRICKY WITH WESTERN HIGHS MAINLY EARLY THIS MORNING BEFORE POST 
FRONTAL COLD ADVECTION KICKS IN THIS AFTERNOON...WHILE EXPECT SOME 
RISES OUT EAST PENDING PRECIP TIMING. GIVEN SUCH A MILD START...WILL 
RAISE HIGHS ABOUT A CATEGORY ACROSS THE BOARD WITH MENTION OF 
FALLING TEMPS ESPCLY WEST LATER ON. 

RATHER STRONG 5H TROF SWEEPS EAST THIS EVENING GIVING THE FRONT A 
LITTLE MORE OF A PUNCH TO THE EAST OVERNIGHT. GUIDANCE SHOWS QUITE A 
CUTOFF IN MOISTURE AFTER 00Z MOST AREAS...AND EVEN LIMIT MUCH IN THE 
NW UPSLOPE REGIONS DESPITE STRONG 85H COLD ADVECTION AND A BRIEF NW 
FETCH THIS EVENING. THIS LOOKS IN RESPONSE TO A QUICK SHOT OF 
SUBSIDENCE AS THE SURFACE RIDGE BUILDS IN PRETTY FAST OVERNIGHT AND 
SHOULD BE JUST TO THE SW LATE. THEREFORE CUT MOST POPS OFF AFTER 00Z 
AND ONLY LEFT A BRIEF PERIOD OF UPSLOPE PRECIP DURING THE EARLY 
EVENING BEFORE CLEARING THINGS OUT MOST ZONES OVERNIGHT. GUSTY WINDS 
ON THE RIDGES ESPCLY NORTH SHOULD KEEP LOW TEMPS UP SOME GIVEN THE 
QUICK NATURE TO THE PASSING 85H TROF. HOWEVER STILL LOOKS COLD 
ENOUGH ALOFT TO GO AT/BELOW FREEZING WEST OVERNIGHT AND MID 30S EAST 
WHERE THE BEST COLD ADVECTION WILL SKIRT BY TO THE NORTH.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
WEAK SHORT WAVE WELL BEHIND THE FRONT EARLY TUESDAY MORNING BRINGS A 
SFC TROUGH ACROSS THE CENTRAL APPLNS AND TIGHTENS THE PRESSURE 
GRADIENT ACROSS THE CWA- MAINLY THE NORTH. THIS INCREASES THE LOW 
LEVEL JET AND MODELS ARE NOW INDICATING A 40 TO 50 KNOT JET. SHOULD 
HAVE SOME GOOD SUBSIDENCE TUE MORNING AS WELL...SO HAVE RAISED WINDS 
TUE MAINLY IN THE MORNING...AND WIND GUSTS AS WELL. LOCATIONS SUCH 
AS ROANOKE...NORTHWARD INTO THE ALLEGHANY HIGHLANDS...LOOK TO BE 
BREEZY. HAVE ADJUSTED MAX TEMPS TUE TO BE WARMER ACROSS THE SRN 
CWA...ESPECIALLY THE PIEDMONT OF NC AND SOUTHSIDE VA AS THE STRONGER 
COLD ADVECTION REMAINS NORTH OF THE CWA WITH MORE OF A WEST WIND 
BEHIND THE FRONT. TUE NIGHT...WITH A PROGRESSIVE FLOW PATTERN THE 
SFC HIGH PRESSURE MOVES EAST OF THE CWA BY WED MORNING. LOW LEVEL 
WINDS BACK TO THE SOUTHWEST WE ARE WARM ADVECTING OVERNIGHT. LOOKS 
LIKE RIDGES MAY BE QUITE A BIT WARMER THAN VALLEYS...AND PIEDMONT 
AREAS WHERE SFC WINDS WILL BE LIGHTER. 

WEDNESDAY...THE CUTOFF LOW CURRENTLY OVER NW MEXICO IS PROGGED TO BE 
KICKED OUT AND PICKED UP BY THE NEXT WAVE ENTERING THE WESTERN U.S. 
ALL MODELS ARE IN AGREEMENT ON THIS...WITH THE MAIN FCST ISSUE THE 
TIMING AND EVENTUAL TRACK OF THE ASSOCIATED SFC LOW PRESSURE. 
CURRENT MODELS OF CHOICE ARE THE GFS/ECMWF WHICH ARE FASTER THAN THE 
NAM. I HAVE RAISED POPS WEDNESDAY...SPEEDING UP THE ARRIVAL OF 
PRECIP. WE ALREADY HAD CATEGORICAL POPS WED NIGHT...WHICH STILL 
LOOKS GOOD. ANOTHER FCST CONCERN FOR WED IS THE STRONG SOUTHEAST JET 
THAT DEVELOPS AHEAD OF THE SFC LOW. THIS WIND DIRECTION TENDS TO 
BRING STRONG WIND GUSTS ON THE DOWNSLOPE SIDE OF THE SW TO NE 
ORIENTED MTNS IN SW VA...PARTICULARLY TAZEWELL COUNTY...BUT ALSO 
SMYTH AND BLAND COUNTIES IN VA...AND MERCER COUNTY WV. I HAVE RAISED 
WIND SPEEDS AND GUSTS WED INTO WED EVENING...WITH SOME GUSTS OF 40 
TO 45 KNOTS IN THE ABOVE MENTIONED LOCATIONS. FINALLY...HIGH TEMPS 
WEDNESDAY HAVE THE POTENTIAL TO BE QUITE WARM...WITH THE STRONG 
SOUTHEAST FLOW AND NO LOW LEVEL DAMMING INDICATED. EVEN WITH CLOUD 
COVER AND PRECIP MOVING IN IN THE AFTERNOON...TEMPS COULD STILL BE 
MILD...SO HAVE RAISED HIGHS MORE INTO THE UPPER 40S TO MID 50S 
RANGE. 

THURSDAY...DRY SLOT WILL BE MOVING INTO THE SWRN CWA TOWARD 
MORNING...SO PRECIP WILL LIKELY END QUICKLY IN THE NE MTNS AND 
FOOTHILLS...BUT COULD LINGER WELL INTO THE DAY IN THE NERN CWA. I 
ADJUSTED THE POPS TO REFLECT HIGHER CHANCES THU MORNING FOR MOST OF 
SW VA AND SE WV.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
SYSTEM WILL BE EXITING THE REGION AND MOVING OVER NEW ENGLAND BY
THURSDAY NIGHT. OVERNIGHT THURSDAY AND INTO FRIDAY
NIGHT...TYPICAL WESTERN UPSLOPE SNOW SHOWERS WILL FALL WITH
FLURRIES AS FAR AS THE BLUE RIDGE. LIGHT ACCUMULATIONS ARE
POSSIBLE ON WESTERN SLOPES...ESPECIALLY ABOVE 3000 FEET DURING THE
OVERNIGHT HOURS THURSDAY AND FRIDAY NIGHT. DURING THE DAY
FRIDAY...TEMPERATURES COULD EDGE ABOVE FREEZING AND SUNSHINE
POKING THROUGH THE CLOUDS FROM TIME TO TIME...COULD MELT/LIMIT
SNOW ACCUMULATIONS. PRIMARILY A WEST WIND WITH NO GREAT LAKE
CONNECTIONS AND DAY TIME MELTING...NOT FORESEEING HIGHLIGHTING IN
HWO AT THIS TIME. EVEN THOUGH SURFACE TEMPERATURES WILL GET ABOVE
FREEZING IN MOST MOUNTAINS LOCATIONS...WARM BOUNDARY WILL BE
SHALLOW AND SNOW SHOWERS/FLURRIES WILL CONTINUE THROUGH THE DAY
FRIDAY. THE WINDS WILL BE BREEZY AND GUSTY IN THE WAKE OF THE
FRONT BUT NOT SEEING ANY CRITERIA BEING MET AT THIS TIME. THESE
WESTERLY WINDS WILL DOWNSLOPE IN THE EAST AND ADD A FEW DEGREES TO
THE TEMPERATURE. HOWEVER...TEMPERATURES WILL BE BELOW NORMAL AND
FEEL CHILLY WITH THE WIND BLOWING.

MOUNTAIN SNOW SHOWERS WILL COME TO AN END FRIDAY NIGHT AS HIGH 
PRESSURE BUILDS INTO THE REGION. OVER THE WEEKEND...A WARM FRONT 
WILL BRING MODERATING TEMPERATURES TO THE AREA BUT STILL REMAIN 
BELOW NORMAL. HIGH PRESSURE WILL REMAIN IN THE REGION THROUGH EARLY 
NEXT WEEK.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
BAND OF SHOWERS WILL CONTINUE TO TRACK EAST ACROSS KBLF/KLWB
EARLY THIS MORNING...REACHING KROA AROUND 13-14Z AND THE FAR
EASTERN SITES BY MID/LATE MORNING. THIS SHOULD RESULT IN PERIODS
OF MVFR VSBYS AS WELL AS MVFR CIGS ADVANCING EAST ACROSS ALL SITES
FOR THE MOST PART. HOWEVER LOCATIONS ACROSS THE WEST MAY SEE CIGS
LOWER TO IFR AS THE SHOWERS START TO WEAKEN AND THE FRONT NEARS
THIS MORNING INTO THE AFTERNOON. GUSTY SOUTHWEST WINDS WILL VEER
MORE WESTERLY OVER THE MOUNTAINS THIS MORNING AND THEN TRANSLATE
EAST OF THE BLUE RIDGE THIS AFTERNOON. ONCE THE FRONT
PASSES...NORTHWEST WINDS GUSTING TO 20-25 KNOTS AT TIMES WILL
PREVAIL ESPCLY AROUND KBLF/KROA INTO EARLY THIS EVENING BEFORE
DIMINISHING. 

AS COLDER AIR SURGES IN...A BRIEF SNOW SHOWER IS POSSIBLE BEHIND
THE FRONT EARLY THIS EVENING AT KBLF/KLWB...WITH MVFR CIGS RISING
OR SCATTERING OUT TO VFR WITH HIGH PRESSURE BUILDING BACK IN FROM
THE WEST.

ANOTHER STORM SYSTEM WILL BRING A GOOD CHANCE FOR SIGNIFICANT RAIN
BY WEDNESDAY MORNING...WITH A MUCH BETTER CHANCE FOR WIDESPREAD
IFR CONDITIONS...POSSIBLY CONTINUING THROUGH THURSDAY. UPSLOPE
SNOW SHOWERS LOOK TO LINGER MVFR CONDITIONS ACROSS SE WVA INTO
FRIDAY WITH VFR ELSW.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...JJ
LONG TERM...RCS
AVIATION...AMS/JH/WP