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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 140042
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
842 PM EDT MON MAY 13 2013

.SYNOPSIS...
COLD HIGH PRESSURE WILL SETTLE OVER THE REGION TONIGHT. A SHIFT
IN THE WEATHER PATTERN TAKES PLACE BY MID-WEEK AS AN UPPER RIDGE
BUILDS OVER THE REGION...AND TEMPERATURES INCREASE TO ABOVE
NORMAL READINGS. A FRONTAL BOUNDARY WILL APPROACH THE AREA ON
THURSDAY AND STALL OVER OR NEAR THE AREA INTO THE START OF THE
WEEKEND.

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 825 PM EDT MONDAY...

GETTING PAST DUSK AND SEEING SHOWERS STARTING TO FADE OVER THE NRN
CWA...AND WILL ALSO SEE CLOUDS START TO GO AWAY SOME AS WELL.
ISSUE OVERNIGHT WILL BE FROST/FREEZE POTENTIAL. LATEST MODELS PLUS
SATELLITE TRENDS SHOW LESS CLOUD COVER EXPECTED OVERNIGHT INTO TUE
MORNING. THE CAVEAT FOR FROST FORMATION AGAIN WILL BE DEWPOINT
DEPRESSION. ATTM...SFC HIGH OVER KY/TN/GULF COAST STATES WILL
SHIFT OVERHEAD LATE TONIGHT. IDEAL DECOUPLING SCENARIO...AND IT
LOOKS LIKE THE POTENTIAL FOR FROST WILL EXIST ACROSS SOUTHSIDE VA
AS WELL. ADDED A FEW MORE COUNTIES TO THE ADVISORY PER SETUP OF
AREAS OF FROST. HALIFAX/PITTSYLVANIA IN SOUTHSIDE VA WITH MOST OF
THE FROST OCCURRING IN THE NRN HALF OF THE COUNTY...AND BOTETOURT
COUNTY. FURTHER WEST WE ARE GETTING TOWARD WAA AND TEMPS STAYING
ELEVATED SOME. NOT OUT OF THE QUESTION FOR THE DEEPER VALLEYS AT
LEAST TO SEE A PATCH OF FROST IN THE MORNING...BUT AREAL COVERAGE
DOES NOT LEAD ME TO ISSUE ANY HEADLINES FOR THIS SECTION.


PREVIOUS VALID DISCUSSION...

ON TUESDAY...THE BACKING OF THE LOW LEVEL WINDS THAT STARTED IN THE
SOUTHWEST LATE MONDAY NIGHT...WILL CONTINUE THROUGHOUT THE DAY
TUESDAY ALONG WITH GENEROUS WARM AIR ADVECTION. BY THE LATE
AFTERNOON 850 MB TEMPS ARE EXPECTED BE AROUND +12C IN THE WEST AND
AROUND +6 IN THE EAST...AS COMPARED TO THE 0C TO +4 C RANGE THAT
EXIST THIS AFTERNOON. EXPECT INCREASING MID TO HIGH LEVEL CLOUDS
THROUGH THE DAY. HIGHS WILL RANGE FROM THE LOW TO MID 60S IN THE
MOUNTAINS WITH UPPER 60S TO AROUND 70 DEGREES EAST OF THE CREST OF
THE BLUE RIDGE.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 345 PM EDT SUNDAY...

MODELS SHOWING HIGHER AMOUNT OF MOISTURE WITH THE WARM FRONT WHICH
CROSSES THE FORECAST AREA TUESDAY AFTERNOON THROUGH LATE TUESDAY
NIGHT. HAVE INCREASED THE AREAL COVERAGE OF LOW PROBABILITY OF
PRECIPITATION IN THE NORTHERN COUNTY WARNING AREA...SIMILAR TO WHAT
WAS SHOWN ON THE SREF AND 00Z ECMWF. ISENTROPIC FORECAST IN THE 295K
LAYER SHOWED GOOD LIFT IN THE 850 TO 700 MB RANGE WITH PLENTY OF
MOISTURE IN THAT LAYER.

COUNTY WARNING AREA WILL BE WELL INTO THE WARM SECTOR ON WEDNESDAY
WITH A LARGE RISE IN 850 MB TEMPERATURES AND SURFACE TO LOW LEVEL
WINDS WITH A DOWNSLOPE WESTERLY COMPONENT. WENT CLOSE TO WARMER
GUIDANCE EAST OF THE BLUE RIDGE FOR MAXIMUM TEMPERATURES ON
WEDNESDAY.

SOME MODELS SHOWING THE FRONT FROM PENNSYLVANIA INTO THE OHIO VALLEY
POTENTIALLY STARTING TO DROP SOUTH ON THURSDAY. WHILE CONVECTIVE
COMPLEXES ALONG THE FRONT MAY MOVE THE BOUNDARY...ZONAL FLOW DOES
NOT SEEM FAVORABLE FOR MUCH OF A SOUTHERN PUSH.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 345 PM EDT MONDAY...

TIMING OF THE SHORT WAVE COMING OUT OF THE SOUTHERN PLAINS SOMEWHAT
SIMILAR TO PAST FEW RUNS BRINGING SOME ENHANCED LIFT INTO THE AREA
THURSDAY NIGHT AND FRIDAY. CHALLENGING TO NARROW DOWN BEST CHANCE OF
PRECIPITATION FRIDAY NIGHT THROUGH SUNDAY NIGHT. LITTLE CHANGE IN THE
AIR MASS AND DAILY HIGHS AND LOWS THROUGH SUNDAY.

NEXT LONG WAVE UPPER TROF DIGGING INTO THE CENTRAL UNITED STATES ON
SUNDAY AND MONDAY. THIS PUSHES A COLD FRONT INTO THE REGION ON
MONDAY. SO HAVE A HIGHER PROBABILITY OF PRECIPITATION FOR MONDAY AND
MONDAY NIGHT.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
AS OF 725 PM EDT MONDAY...

CU WILL CONTINUE TO DISSIPATE THIS EVENING. ALSO WINDS WILL
WEAKEN. VFR CONDITIONS ARE EXPECTED THROUGH AT LEAST WEDNESDAY.

OUR NEXT CHANCE OF ORGANIZED PRECIPITATION AND AREAS OF SUB-VFR
CONDITIONS WILL BE THURSDAY NIGHT THROUGH SATURDAY WHEN A FRONTAL
SYSTEM MOVES INTO AND THEN STALLS NEAR THE REGION.

&&

.CLIMATE...
A NEW RECORD LOW WAS ESTABLISHED AT DANVILLE THIS MORNING WITH 37
DEGREES. THE PREVIOUS RECORD WAS 38 DEGREES FROM 1989. ALSO...A
LOW OF 35 DEGREES THIS MORNING TIED THE RECORD LOW AT LYNCHBURG.
THE LAST OCCURRENCE WAS IN 1969.

LOW TEMPERATURES TUESDAY MORNING WILL FLIRT WITH RECORD LOW
TEMPERATURES AT ALL CLIMATE LOCATIONS. THE FOLLOWING ARE THE
CURRENT RECORD LOW TEMPERATURES FOR MAY 14 ALONG WITH THE YEAR OF
THAT RECORD.

MAY 14
ROA...37...1996
LYH...33...1997
RNK...31...1996
DAN...38...2007
BLF...33...1996

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
VA...FREEZE WARNING FROM 1 AM TO 9 AM EDT TUESDAY FOR VAZ019-020-
     024.
     FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR VAZ023-034-
     035-044>047-058-059.
NC...NONE.
WV...FREEZE WARNING FROM 1 AM TO 9 AM EDT TUESDAY FOR WVZ045.
     FROST ADVISORY FROM 1 AM TO 9 AM EDT TUESDAY FOR WVZ043.
-- End Changed Discussion --

&&

$$
SYNOPSIS...DS
NEAR TERM...DS/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...DS/KM
CLIMATE...CF/DS