-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 200153
AFDRNK

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

.SYNOPSIS...
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.

&&

.NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
AS 0F 950 PM EDT WEDNESDAY...

JUST A FEW LINGERING SHOWERS ARE OVER THE AREA THIS EVENING. WITH
EVERY VOLUME SCAN....THEY ARE GETTING SMALLER AND SMALLER. WILL
KEEP SCATTERED SHOWERS IN THE FORECAST FOR PATRICK...SURRY AND
WILKES COUNTY THROUGH MIDNIGHT. THIS IS THE STRONGEST STORM AND
CONTINUES TO DRIFT INTO SOME LINGERING INSTABILITY.

SOME LOW/DEBRIS CLOUDS MAY FADE WITH STABILITY OVERNIGHT. ANY
CLEARING WILL LEAD TO FOG DEVELOPING OVERNIGHT...ESPECIALLY ACROSS
THE NEW RIVER...ROANOKE AND SOUTHERN SHENANDOAH VALLEYS WHERE
MOST OF THE RAIN FELL THIS EVENING.TWEAKED OVERNIGHT LOWS WITH
50S ACROSS THE WEST AND LOWER 60S IN THE EAST.

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. FORECAST 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/...
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.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
AS OF 730 PM EDT WEDNESDAY...

SCATTERED TO BROKEN MVFR CLOUDS EXPECTED INTO THIS EVENING AS
FLOW SLOWLY TURNS MORE EAST TO SOUTHEAST ESPECIALLY ALONG AND
EAST OF THE BLUE RIDGE. MODELS SUGGEST SOME SHRA/TSRA POTENTIAL AT
BCB AND ROA THIS EVENING. CONVECTION HAS CLEARED THESE TWO AIRPORT
ALREADY. REMAINING INSTABILITY MAY BRING SHRA TO LWB/LYH/DAN BY
SUNSET. SHOWERS ON RADAR AT 2330Z/730P SHRINKING IN SIZE AND
MOVING VERY SLOWLY TO THE SOUTH-SOUTHEAST. DO NOT HAVE ENOUGH
CONFIDENCE TO INCLUDE IN TAFS. WILL AMMEND IF THEY MOVING INTO THE
VICINTY OF THESE AIRPORTS.

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/RCS
SHORT TERM...PM
LONG TERM...PM
AVIATION...KK/RCS