-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 231746
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
146 PM EDT THU MAY 23 2013

.SYNOPSIS...
A STRONG COLD FRONT WILL MOVE THROUGH THE REGION FROM WEST TO EAST
THIS AFTERNOON AND TONIGHT. MEANWHILE...A DEEP UPPER LOW WILL
SWING THROUGH THE OHIO VALLEY AND MID-ATLANTIC REGION THROUGH
SATURDAY...THEN SHIFT OFF THE MID-ATLANTIC COAST SUNDAY. HIGH
PRESSURE AT THE SURFACE AND ALOFT WILL BUILD ACROSS THE REGION
SUNDAY THROUGH THE FIRST PART OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1155 AM EDT THURSDAY...

CLOUD COVER IS KEEPING SHOWERS LIMITED ATTM...BUT EXPECTING MORE
BREAKS ESPECIALLY IN THE WEST TO ALLOW FOR MORE FORMATION THIS
AFTERNOON WHILE AT THE SAME TIME THE PIEDMONT GETS INTO BETTER
DYNAMICS. MODELS ARE VARYING WITH THE HIGH-RES SHOWING TWO TO
THREE AREA WHERE STORM DEVELOPMENT COULD BE HIGHEST THIS
AFTERNOON...ONE ACROSS SE WV INTO THE HIGHLANDS OF BATH...THE
OTHER ALONG THE BLUE RIDGE AND ANOTHER INTO THE PIEDMONT EAST OF
LYH/DAN. WILL LEAN TOWARD A HIGHER THREAT IN THE PIEDMONT WEST TO
THE BLUE RIDGE WITH LOWER POPS IN THE SOUTHWEST...AND ANOTHER
HIGHER THREAT IN THE NW. ADDED HEAVY RAIN AND GUSTY WINDS THIS
AFTERNOON AS WELL.

OTHERWISE...NO MAJOR CHANGES TO THE FORECAST.



PREVIOUS VALID DISCUSSION...


FOR TONIGHT INTO FRI MORNING...OUR ATTENTION WILL TURN TO AN
ANOMALOUSLY DEEP UPPER LOW...A RECURRING PATTERN SINCE MID-
WINTER...PROGGED TO SETTLE ACROSS THE MID-ATLANTIC INTO THE
WEEKEND. A SECONDARY VORT LOBE WILL SWEEP THROUGH LATE
TONIGHT...AND BRING WINTERLIKE UPSLOPE CLOUDS/-SHRA TO THE
WESTERN SLOPES OF THE ALLEGHANYS...MAINLY IN EASTERN WV.
INCREASING DOWNSLOPE SHOULD END PCPN ACROSS THE PIEDMONT...WITH
ONLY SMALL CHANCES FOR THE REMAINDER OF THE CWA OUTSIDE THE FAR
WESTERN SLOPES OF SW VA/NW NC...AND SE WV AS MENTIONED ABOVE.
TEMPERATURES WILL BE NOTICEABLY COOLER BY EARLY FRI AS WE ENTER A
PERIOD OF WELL BELOW NORMAL TEMPERATURES THAT WILL LAST INTO THE
WEEKEND.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 400 AM EDT THURSDAY...

FOR FRIDAY MORNING...WILL BE UNDER A WEATHER PATTERN FOUND MORE
OFTEN DURING THE WINTER MONTHS...ALBEIT WARMER...WITH AN 8MB
PRESSURE GRADIENT SITUATED ACROSS OUR AREA AS CANADIAN HIGH PRESSURE
BUILDS IN FROM THE UPPER MIDWEST. WILL START THE DAY WITH RESIDUAL
SHOWER ACTIVITY ACROSS THE MOUNTAINS THAT WILL LINGER INTO EARLY
AFTERNOON...BUT THE MAIN CONCERN WILL BE STRONG NORTHWEST WINDS THAT
WILL REMAIN ACROSS THE REGION THROUGH THE DAY. WITH CLOUD COVER
CLEARING OUT EARLY...THE STRONGER WINDS ALOFT WILL MIX DOWN TO THE
SURFACE DURING THE MORNING...AND WILL NOT BE SURPRISED TO SEE 30+
MPH GUSTS COMMON ACROSS THE MOUNTAINS AND 25 MPH GUSTS ACROSS THE
PIEDMONTS. GUSTS WILL BE STRONGER ABOVE 3000 FEET...AND BELIEVE WE
WILL SEE ADVISORY LEVEL GUSTS ACROSS THE NORTH CAROLINA MOUNTAINS
INTO SOUTHWEST VIRGINIA. THE CANADIAN HIGH PRESSURE WILL BRING
SIGNIFICANTLY COOLER TEMPERATURES...WITH FRIDAY AFTERNOON HIGHS
RANGING FROM THE UPPER 50S TO THE LOW 60S ACROSS THE MOUNTAINS...TO
THE LOW 70S ACROSS THE PIEDMONTS. KEEP IN MIND THAT THE GUSTY WINDS
MAY ADD AN ADDITIONAL CHILL TO THE AIR...SO KEEPING A LIGHT JACKET
HANDY MAY BE A GOOD IDEA.

WINDS WILL REMAIN SOMEWHAT GUSTY SATURDAY...ALTHOUGH NOT AS STRONG
AS THOSE ON FRIDAY...AS A LOW PRESSURE SYSTEM DEEPENS OFF THE NEW
ENGLAND COAST. WILL START THE MORNING OFF WITH RATHER COOL
TEMPERATURES...RANGING FROM THE MID/UPPER 30S ACROSS THE MOUNTAINS
TO THE MID 40S FURTHER EAST. BELIEVE WINDS WILL REMAIN STRONG ENOUGH
TO PREVENT FROST FROM DEVELOPING IN THE COOLER SPOTS IN THE
MOUNTAINS...HOWEVER THOSE WITH TENDER VEGETATION SHOULD KEEP AN EYE
ON THE FORECAST JUST THE SAME...AND BE PREPARED TO PROTECT THESE
PLANTS IF NECESSARY. AT ANY RATE...TEMPERATURES WILL REBOUND INTO
THE LOW/MID 60S WEST...TO THE LOW 70S EAST BY AFTERNOON.

HIGH PRESSURE REMAINS IN CONTROL OF THE WEATHER PATTERN ON SUNDAY...
ALTHOUGH TEMPERATURES WILL BEGIN TO MODERATE AS LOW PRESSURE OVER
NEW ENGLAND BEGINS TO PUSH NORTHEAST INTO CANADA. WEATHER IS
EXPECTED TO REMAIN DRY ONCE AGAIN...BUT WILL BE KEEPING AN EYE ON A
WARM FRONT STRETCHING FROM THE LOWER GREAT LAKES TO THE CENTRAL
APPALACHIANS THAT WILL LIFT NORTHWARD DURING THE DAY. THIS WARM
FRONT WILL PLAY A ROLE IN OUR WEATHER AS WE GET INTO THE NEXT
WORKWEEK.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1245 PM EDT WEDNESDAY

EXPECT COOL TROUGH TO LINGER INTO SUNDAY BEFORE LIFTING EAST.
MEANWHILE A STRONG TROUGH DIGS INTO THE PACIFIC NORTHWEST BY MONDAY
WITH INCREASING HEIGHTS ARRIVING OVER OUR AREA NEXT WEEK. THE
WEATHER PATTERN WILL BE MAINLY DRY SAT NIGHT-MONDAY...BUT AS WE CAN
SEE WITH A WESTERLY FLOW ALOFT THE CHANCE THAT CONVECTION THAT FIRES
ALONG A WARM FRONT OVER THE OHIO/MID MISSISSIPPI VALLEY COULD SHIFT
EAST AND AFFECT OUR MOUNTAINS.

WILL LEAN TOWARD AN ECMWF/WPC BLEND SOLUTION. THIS WILL KEEP THE
CHANCE POPS IN THE AREA BY MONDAY AFTERNOON THROUGH TUESDAY. THE
WARM FRONT LIFTS NORTH TOWARD THE GREAT LAKES BY MIDWEEK WITH
HEIGHTS CONTINUING TO BUILD. AT THE SFC...HIGH PRESSURE WILL BE
SITUATED ACROSS THE MID ATLANTIC COAST THEN SHIFT OFF THE COAST
MIDWEEK. DEWPOINTS WILL BE INCREASING AGAIN BY NEXT WEEK WITH TEMPS
WARMING BACK TO NORMAL OR JUST ABOVE.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 140 PM EDT THURSDAY...

EXPECT SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH
BULK OF ACTIVITY NORTH OF A LWB-ROA-DAN LINE. CANNOT RULE OUT
THUNDER AT ALL SO AM HOLDING ONTO VCTS THIS AFTERNOON AND KEEPING
RAINFALL IN THE TEMPO GROUP. AS THE FRONT MOVES IN THIS EVENING
WINDS SHIFT TO THE WEST AND SHOWERS WILL END OVER THE NEW RIVER
VALLEY EAST INTO THE PIEDMONT WHILE WESTERN AREAS KEEP THE SHOWERS
AROUND INTO THE OVERNIGHT...BUT MAINLY SCATTERED.

MODELS HAVING SOME LOWER CLOUDS INTO THE BLF/LWB AREA TONIGHT AND
WITH SFC WINDS PICKING UP THINK IFR CIGS AT BLF A GOOD
POSSIBILITY WHILE LWB DROPS TO MVFR TO AT TIMES IFR.

FURTHER EAST CIGS WILL BE VFR ALTHOUGH BCB COULD FALL INTO MVFR
FOR A FEW HOURS AROUND DAWN.

WINDS WILL BE PICKING UP IN EARNEST FRIDAY MORNING WITH GUSTS TO
30 KNOT POSSIBLE ACROSS BCB/ROA. THE DRY AIRMASS SHOULD BRING
ABOUT VFR AT ALL SITES BY THE END OF THE TAF PERIOD.



HIGH PRESSURE TO KEEP US VFR THROUGH THE WEEKEND. MOISTURE
INCREASES AGAIN NEXT WEEK AS THE SFC HIGH MOVES EAST AND THE UPPER
RIDGE STRENGTHENS OVER THE MISSISSIPPI VALLEY. WILL BE GETTING TO
MORE HUMID WEATHER AGAIN WITH SOME THUNDERSTORM THREAT BY TUESDAY
AND FOG ISSUES AT NIGHT IN THE VALLEYS.
-- End Changed Discussion --

&&

.EQUIPMENT...
THE NOAA WEATHER RADIO AT ROANOKE VIRGINIA IS OFF THE AIR DUE TO
A POWER PROBLEM AT THE TRANSMITTER SITE. TECHNICIANS ARE ENROUTE
TO WORK ON IT BY THIS AFTERNOON.

&&

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

&&

$$
SYNOPSIS...RAB/WP
NEAR TERM...RAB/WP
SHORT TERM...NF
LONG TERM...WP
AVIATION...WP
EQUIPMENT...WP