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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 191959
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
359 PM EDT WED JUN 19 2013

.SYNOPSIS...
-- Changed Discussion --
A WEAK COLD FRONT WILL DRIFT SOUTH ACROSS THE REGION TONIGHT. HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH OVERNIGHT AND
THURSDAY...RESULTING IN SOMEWHAT DRIER WEATHER INTO THE END OF THE
WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
AS 0F 330 PM EDT WEDNESDAY...

KFCX WSR-88D LOOP SHOWED SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS MOVING SOUTHEAST. MAIN FOCUS OF CONVECTION THIS
AFTERNOON WILL BE ALONG AND EAST OF THE BLUE RIDGE MOUNTAINS. AS
FLOW TURNS NORTHWARD THIS AFTERNOON INTO THIS EVENING...STORMS MOVE
SOUTH ACROSS THE FOOTHILLS AND PIEDMONT. A WEAK COLD FRONT WILL
TRAVEL SOUTH ACROSS SOUTHERN PORTIONS OF CWA TONIGHT. ANY DIURNALLY-
DRIVEN CONVECTION SHOULD DISSIPATE THIS EVENING INTO TONIGHT. THE
COMBINATION OF MOIST GROUND...SOME CLEARING WITH LIGHT WINDS
SHOULD LEAD TO THE DEVELOPMENT OF FOG AND STATUS OVERNIGHT INTO
THURSDAY MORNING. PLAYED LOW TEMPERATURES TONIGHT CLOSE TO THE
ADJMAVBC WITH READINGS FROM THE LOWER 50S IN THE NORTHWEST MOUNTAINS
TO THE LOWER 60S IN THE PIEDMONT.

HIGH PRESSURE LOCATED OFF THE NEW ENGLAND COAST WILL RIDGE INTO THE
AREA PRODUCING AN EASTERLY FLOW IN THE SOUTHERN APPALACHIANS. A LOW
LEVEL CONVERGENCE ZONE ALONG THE MOUNTAINS THURSDAY SUPPORTS
ISOLATED TO SCATTERED POPS. WENT WITH HIGHS THURSDAY FROM THE MID
70S IN THE MOUNTAINS TO THE LOWER 80S IN THE SOUTHEAST.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
AS OF 345 PM EDT WEDNESDAY...

SURFACE HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL EXTEND
INLAND THROUGH THE WEEKEND AND GRADUALLY STRENGTHEN IN RESPONSE
TO BUILDING 5H HEIGHTS. THIS WILL ALLOW FOR A LOW LEVEL EASTERLY
FETCH AROUND THE HIGH...WITH THE FLOW VEERING MORE SE ALONG AND
WEST OF THE BLUE RIDGE. MODELS SHOW A LOW LEVEL CONVERGENCE ZONE
MAINLY WEST OF INTERSTATE 77 DURING THE PERIOD WHICH WILL BE FOCUS
FOR SOME LOW LEVEL CUMULUS DEVELOPMENT AND ISOLD AFTN/EVE
SHOWERS THERE. FLOW EAST OF THE MTNS WILL BE PRIMARILY DRY WITH
THE EXCEPTION OF AN AREA OF DISTURBED WEATHER WHICH WILL PERSIST
NEAR THE CAROLINA COAST. FORECST BUFKIT SOUNDINGS FOR THE CWA LOOK
PRETTY BENIGN THROUGH SATURDAY...DOMINATED BY SUBSIDENCE AND DRY
AIR ALOFT.

MIX DOWN OF SOMEWHAT LOWER DEWPOINT AIR SHOULD KEEP HUMIDITY
LEVELS IN CHECK...PROMOTING A GOOD DIURNAL SPREAD IN TEMPS FROM
THE UPR 70S-MID 80S FOR HIGHS...TO PLEASANT 50S/LOW 60S FOR LOWS.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
AS OF 345 PM EDT WEDNESDAY...

GRADUAL UPTICK OF BOTH TEMPERATURE AND DEWPOINT EXPECTED EARLY
NEXT WEEK. MODELS ARE IN AGREEMENT THE SUBTROPICAL RIDGE WILL
STRENGTHEN AND RETROGRADE TO THE WEST...BUT DIFFER IN HANDLING
DAY-TO-DAY DETAILS AS FAR AS EMBEDDED SHORT WAVE ENERGY.
AS SUCH...CONFIDENCE IS REASONABLY GOOD FOR RAISING TEMPERATURES
DURING THE PERIOD...BUT BELOW AVERAGE FOR PROBABILITY OF RAINFALL.
MODELS DIFFER IN THE HANDLING OF THE DISTURBED WEATHER ALONG THE
CAROLINA COAST...THE GFS DRAWING IT WESTWARD AND NORTHWARD.
GIVEN THAT RISING HEIGHTS ARE ANTICIPATED DURING THIS PERIOD AND
CONCERNS THAT THE CONVECTIVE PARAMETRIZATION OF THE GFS MAY BE TOO
AGGRESSIVE...THE PREFERENCE IS FOR AN ECMWF-LIKE SCENARIO THAT
MAINTAINS MOST OF THE PRECIPITATION ALONG THE SOUTHEAST COAST.
EVEN SIDING WITH THE ECMWF...AT SOME POINT WE WARM AND MOISTEN
ENOUGH TO SUPPORT DAILY THREAT OF SCATTERED DIURNAL DEEP
CONVECTION OVER THE MTNS ANYWAY...SO FEEL SCATTERED AFTN/EVE
SHRA/TSRA BECOME WARRANTED FOR MONDAY AND BEYOND IN SPITE OF THE
MODEL DIFFERENCES.
-- End Changed Discussion --

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
AS OF 115 PM EDT WEDNESDAY...

SCT TO BKN MVFR CLOUDS EXPECTED THIS AFTERNOON AS FLOW
SLOWLY TURNS MORE EAST TO SOUTHEAST ESPCLY ALONG AND EAST
OF THE THE BLUE RIDGE. LATEST MODELS INCLUDE RNK WRFARW
AND NAM SUGGEST SOME SHRA/TSRA POTENTIAL MAINLY KROA/KLYH/KDAN.
HIGHLIGHTED THIS POTENTIAL WITH VCTS IN TAF. TAF SITE WITH THE
BEST CHANCE FOR A THUNDERSTORM IS LYH. OTRW LEAVING OUT PRECIP
MENTION GIVEN ISOLATED NATURE ELSW. LEFTOVER CLOUDS AND WIDELY
SCATTERED CONVECTION MAY LINGER INTO TONIGHT ALONG THE BLUE RIDGE
CORRIDOR WITH MOST OF THIS COVERAGE LIKELY ENDING UP SOUTH OF THE
TERMINALS BEFORE ENDING LATER WED NIGHT. FOG/STRATUS EXPECTED
TONIGHT INTO THURSDAY MORNING. CONFIDENCE HIGH ON SUB VFR AT MOST
SITES. MVFR CIGS WITH IFR/LIFR VSBYS ARE POSSIBLE IN FAVORED
LOCATIONS.

FOR THURSDAY INTO THE WEEKEND...CONTINUED DIURNAL
CONVECTION...ESPECIALLY ALONG THE APPALACHIANS...WITH LOCALLY
BRIEF MVFR-IFR CIGS/VSBYS IN TSRA. AREAS OF MVFR-IFR VSBYS
BR...LOCALLY IFR FG...ALSO POSSIBLE DURING THE MORNING HOURS. OTRW
OVERALL VFR DURING THE DAYTIME HOURS BEFORE/AFTER ANY RIDGE
ORIENTED CONVECTION DEVELOPS.

&&

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

&&

$$
SYNOPSIS...KK
NEAR TERM...KK/WP
SHORT TERM...PM
LONG TERM...PM
AVIATION...JC/JH/KK/WP