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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
1054 PM EDT FRI OCT 31 2014

.SYNOPSIS...
LOW PRESSURE OVER OHIO WILL DIVE SOUTH INTO THE SOUTHERN 
APPALACHIANS TONIGHT...THEN OFF THE CAROLINA COAST ON
SATURDAY...WHEN IT WILL RAPIDLY DEEPEN AND MOVE NORTHEAST. THIS
SYSTEM WILL BRING RAIN AND THE REGIONS FIRST SNOW IN THE SOME
PARTS OF THE MOUNTAINS...AS WELL AS GUSTY WINDS AND UNSEASONABLY
COLD AIR. HIGH PRESSURE BUILDS IN ON SUNDAY AND SUNDAY NIGHT
FOLLOWED BY MODERATING TEMPERATURES FOR NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1030 PM EDT FRIDAY...

00Z RNK SOUNDING SHOWS THE FREEZING LEVEL AROUND 4500 FT MSL.
REPORTS STARTING TO COME IN OF SNOW ON GRASSY SFCS IN WRN
GREENBRIER COUNTY...WHILE EARLIER THIS EVENING BEECH MTN HAS A
DUSTING ON THE GRASS.

POTENT UPPER LOW NOW OVER WRN KY AND MODELS STILL CONSISTENT IN
MOVING IT INTO THE SMOKYS BY 2AM...THEN UPSTATE SC BY 8 AM
SATURDAY. BEST COLD ADVECTION ARRIVING MORE OF THE SMOKYS THAN UP
OUR WAY...AS THE NOSE OF THE COLDEST 8H AIR SHIFTS INTO MID TN PER
LATEST SPC MESOANALYSIS.

MAINLY STILL SEEING AREA OF RAIN ACROSS THE CWA...SLOWLY MAKING
ITS WAY TO LYH/DAN...WITH LACK OF PRECIP UPSTREAM UNTIL YOU GET
INTO ERN KY/SE TN. 

AS UPPER LOW MOVES SOUTHEAST THE AREA OF PRECIP SITUATED FROM THE
NC PIEDMONT NNW INTO THE ROANOKE VALLEY WILL PIVOT AROUND AND
GENERALLY LINE UP FROM THE NC TRIANGLE INTO FAR SW VA/SRN WV BY
DAWN. WITH THE VORT PASSING OVER UPSTATE SC AND 8H LOW MOVING IN
ACROSS FAR SW NC/UPSTATE SC...STILL OVERALL FAVORS HIGHER SNOWFALL
TOTALS OVER THE SMOKYS NORTHEAST INTO THE GRAYSON HIGHLANDS. THINK
THE SNOWFALL IN THE WV MTNS WILL BE LESS...LATER OVERNIGHT BUT
KICKING BACK IN SATURDAY MORNING WITH NW FLOW SETTING UP AS THE
SFC/8H LOW MOVE OFF THE NC COAST.

LOWERED TEMPS A FEW DEGREES BASED ON LATEST READINGS AND TRENDS.
NUDGED THE TOTAL SNOWFALL UP AN INCH OR TWO IN THE WRN GREENBRIER
BASED ON SOME INCOMING SNOW REPORTS...THOUGH NO MEASURED AMOUNTS
YET.

PER COORDINATION WITH WFO RLX WILL NOT PUT ANY SE WV COUNTIES IN
AN ADVISORY AS NOT EXPECTING TO REACH THE 3 INCH ACCUMULATION IN
OVER HALF THE COUNTIES.

PREVIOUS VALID DISCUSSION...


LOW PRESSURE WILL TRACK TO CAROLINA COAST BY SATURDAY
MORNING...BEFORE DEEPENING AND BECOMING THE PRIMARY LOW OFFSHORE
ON SATURDAY NIGHT.

STRONG Q-VECTOR FORCING TONIGHT WITH THE BEST LIFT FROM 8PM FRIDAY 
TO 8PM SATURDAY. DECENT ISENTROPIC LIFT NEAR 290K FROM MIDNIGHT 
THROUGH NOON ON SATURDAY. BULK OF THE ACCUMULATING SNOW OUTSIDE
THE WESTERN SLOPES WILL BE IN THIS TIME FRAME.  

SATURDAY AFTERNOON AS THE LOW DEEPENS OFF THE COAST...850 MB WINDS 
INCREASE TO AROUND 50 KNOTS FROM THE NORTH-NORTHWEST...WITH THE 
STRONGEST JET ALONG THE BLUE RIDGE. NAM WAS SHOWING GOOD PRESSURE 
RISES AS THE LOW MOVES OUT TO AND DEEPENS...PEAKING AT NEARLY 
8MB/6HRS LATE SATURDAY EVENING. MODEL CROSS SECTIONS PERPENDICULAR 
TO THE BLUE RIDGE SHOWED THE POTENTIAL FOR 40 KNOT WINDS ON SATURDAY 
AFTERNOON AND EVENING. MAY NEED A WIND ADVISORY FOR MUCH OF THE
BLUE RIDGE AND ADJACENT EASTERN FOOTHILL COUNTIES BY SATURDAY
AFTERNOON. STILL NOT ENOUGH SNOW ACCUMULATION EXPECTED...EVEN ON
WESTERN SLOPES IN SOUTHEAST WEST VIRGINIA TO NEED AN ADVISORY AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
AS OF 400 PM EDT FRIDAY...

SURFACE LOW EXPECTED TO BE WELL OUT INTO THE WESTERN ATLANTIC BY 
SUNDAY MORNING WITH ONLY SOME RESIDUAL UPSLOPE SNOW SHOWERS IN THE 
FAR WESTERN MOUNTAINS FOR A FEW HOURS UNTIL AROUND MIDDAY. THE UPPER 
TROUGH AND ITS ASSOCIATED POCKET OF VERY CHILLY AIR WILL LIFT OUT 
VERY QUICKLY DURING THE DAY SUNDAY WITH H85 TEMPS REBOUNDING FROM 
THE VICINITY OF -5C TO +5C BY EARLY MONDAY. SUNDAY WILL REMAIN 
CHILLY AND BREEZY AS THE LOW DEPARTS WITH HIGHS RUNNING AROUND 15F
BELOW NORMAL FOR EARLY NOVEMBER. WITH A 1032 OR SO MB SURFACE HIGH
CENTERED ACROSS THE WESTERN MOUNTAINS SHOULD SEE SOME EXCELLENT
RADIATIONAL COOLING SUNDAY NIGHT WITH THE COLDEST LOWS OF THE FALL
SEASON BY EARLY MONDAY. VARIOUS GUIDANCE SUGGESTS LOWS RANGING
FROM LOW 20S (AND EVEN A FEW HIGH TEENS) IN WESTERN VALLEYS TO
NEAR 30 FAR EAST WHICH IS ENTIRELY CREDIBLE ESPECIALLY WITH SOME
POSSIBLE SNOW COVER IN THE WESTERN ZONES ALTHOUGH REMAINING SNOW
COVER LIKELY TO BE AT HIGHER ELEVATIONS WHERE RADIATIONAL
CONDITIONS LESS IDEAL. FOR LOWS WENT WITH A MODEL BLEND PUTTING
ENTIRE CWA INTO A FREEZE BY MONDAY MORNING. UPPER RIDGE CONTINUES
TO BUILD EASTWARD ON MONDAY WITH SURFACE HIGH SHIFTING FROM THE
MOUNTAINS TO THE SOUTHEAST COAST. SUNNY SKIES WILL PREVAIL WITH
MUCH WARMER TEMPS CLIMBING BACK TOWARD NORMAL..L/M 60S FOR HIGHS.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 400 PM EDT FRIDAY...

RIDGING ALOFT AND SURFACE HIGH PRESSURE WILL CONTINUE IN CONTROL OF 
WEATHER TUESDAY AND EARLY WEDNESDAY WITH THE NEXT FEATURE OF ANY 
NOTE A COLD FRONT WHICH WILL BE MAKING ITS WAY FROM THE CENTRAL U.S. 
TO THE WESTERN MOUNTAINS OF THE FORECAST AREA BY WEDNESDAY NIGHT. 
THIS FRONT DOES NOT APPEAR PARTICULARLY IMPRESSIVE AT THIS TIME WITH 
UPPER LEVEL SUPPORT WELL TO THE NORTH...LIMITED MOISTURE AND A WEAK 
AIR MASS CHANGE BEHIND IT. FRONTAL PASSAGE COULD BE SIMILAR TO 
SEVERAL RECENT ONES IN THE LAST HALF OF OCTOBER WITH RAINFALL 
AMOUNTS ON THE ORDER POSSIBLY A TENTH OF AN INCH ACROSS THE 
MOUNTAINS AND EVEN LESS OR NOTHING EAST OF THE BLUE RIDGE. THE LAST 
TWO WEEKS HAVE BEEN VERY DRY IN OUR EASTERN AND SOUTHEASTERN 
COUNTIES AND ABNORMALLY DRY CONDITIONS HAVE BEEN DEPICTED ON THE 
U.S. DROUGHT MONITOR FOR PARTS OF THAT AREA WITH RAINFALL DEFICITS 
RUNNING FROM 2 TO 4 INCHES OVER THE PAST 60 DAYS. THE LONG TERM 
FORECAST DOES NOT SEEM TO OFFER MUCH HOPE TO CHANGE THAT
SITUATION.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
AS OF 735 PM EDT FRIDAY...

FOLLOWED CLOSE TO THE 18Z NAM/WRF...AND STILL LOOKS LIKE POOR
FLYING CONDITIONS WILL TAKE SHAPE OVERNIGHT INTO SATURDAY...THOUGH
IMPROVING IN THE EAST BY SATURDAY AFTERNOON CIGS/VSBY WISE. 

LOOK FOR RAIN TO CHANGE WITH MIX WITH SNOW AT BLF/LWB AROUND 7Z
SAT...WITH MIXED RAIN/SNOW AT BCB AROUND 08Z. ALL RAIN FURTHER
EAST. CIGS/VSBYS WILL FLUCTUATE AT TIMES WITH MODERATE RAIN AND
SNOW BUT OVERALL EXPECT IFR/LIFR AFTER MIDNIGHT IN THE MTNS...TO
IFR EAST.

DURING THE DAY SATURDAY THE LOW WILL MOVE OFF THE NC COAST WITH
STRONG WINDS TAKING SHAPE FROM A NW TO NNE DIRECTION. DOWNSLOPING
WILL BE CAUSING CIGS TO RISE IN THE EAST TO VFR SATURDAY AFTERNOON
WHILE THE MTNS STAY STUCK IN NO BETTER THAN MVFR. PRECIP WILL
TAPER OFF IN THE MORNING IN THE EAST AND BY MID AFTERNOON AT
BCB/LWB. MORE SNOW SHOWERS ARE POSSIBLE SAT NIGHT AT LWB/BLF WITH
CIGS STAYING UNDER VFR.

LOOKING AT GUSTY WINDS AROUND 20-30 KNOTS...SUSTAINED 10-15
KTS...BUT SVR TURBULENCE CAN BE EXPECTED.
 
VFR CONDITIONS WILL RETURN TO THE AREA SUNDAY...WINDS GRADUALLY
DIMINISHING. VFR EXPECTED INTO MIDWEEK THOUGH A FRONT ARRIVES BY
LATE WEDNESDAY BUT LOOKS LIMITED IN MOISTURE.

&&

.EQUIPMENT...
THE AC UNITS FOR THE RADAR SHELTER ARE BAD. RADAR OPERATION WILL
BE INTERMITTENT UNTIL SUCH TIME THE AC UNITS ARE FIXED.
IF SHELTER TEMPERATURES RISE ABOVE CRITICAL LEVELS WE WILL PLACE
THE RADAR INTO STANDBY TO AVOID DAMAGE TO THE TRANSMITTER.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER STORM WARNING UNTIL 8 PM EDT SATURDAY FOR VAZ007-009-
     015.
NC...WINTER STORM WARNING UNTIL 8 PM EDT SATURDAY FOR NCZ001-018.
WV...NONE.

&&

$$
SYNOPSIS...AMS
NEAR TERM...AMS/WP
SHORT TERM...PC
LONG TERM...PC
AVIATION...AMS/WP
EQUIPMENT...AMS

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