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000
FXUS61 KRNK 191137
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
737 AM EDT WED JUN 19 2013

.SYNOPSIS...
A WEAK COLD FRONT WILL DRIFT SOUTH INTO THE AREA TODAY. WEAK HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH LATER WEDNESDAY
NIGHT AND THURSDAY...RESULTING IN SOMEWHAT DRIER WEATHER INTO THE
END OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 330 AM EDT WEDNESDAY...

PAIR OF FRONTS CURRENTLY ACROSS THE REGION. FIRST WITH THE DEEP
CONVECTION HAS MOVED SOUTH OF US AND WAS LOCATED FROM NRN GA TO NE
NC EARLY THIS MORNING. THE SECONDARY FRONT WITH DRIER AIR BEHIND IT
WAS LAYED OUT FROM CVG-CRW-NRN VA. SOME LOWER DEWPOINTS HAVE SEEPED
SWD INTO THE MTNS...WITH TEMPS CLOSE TO THEM ALLOWING FOG TO FORM
GIVEN WET GROUND AND SCATTERING OUT OF CLOUDS. THIS FOG WILL BE
LINGERING THRU MID MORNING BEFORE DISSIPATING.

SHOWERS HAVE BEEN SCARCE AND MAINLY NORTH OF THE MTNS OF SE WV THIS
MORNING. THE 00Z NAM/LOCAL WRF ALONG WITH SPC WRF WAS FOLLOWED
THROUGH THE DAY GIVEN ITS INITIALIZATION OF THE FEW SHOWERS. THERE
IS AGREEMENT THAT THOSE EARLIER SHOWERS WILL LEAVE ENOUGH OF A
BOUNDARY TO REFIRE MORE BY MIDDAY ACROSS THE ALLEGHANY FRONT EAST TO
THE BLUE RIDGE...THEN FLOW TURNS NORTH SENDING THE SHOWERS SOUTH
ACROSS THE VA FOOTHILLS AND PIEDMONT WITH INSTABILITY INCREASING
THIS AFTERNOON ALLOWING FOR SOME THUNDERSTORMS TO FORM. AT THE
MOMENT CONFIDENCE NOT HIGH ENOUGH TO GO LIKELY POPS AND THINK WILL
SEE MORE SCATTERED IN NATURE TO THE CONVECTION...BUT STILL LOOKS
LIKE AREAS FROM HOT SPRINGS AND LEXINGTON VA SOUTH THROUGH THE
ROANOKE VALLEY AND INTO SOUTHSIDE HAVE A BETTER CHANCE TODAY THAN
AREAS FURTHER WEST. HAVE BROADBRUSHED SOME LOWER CHANCES IN THE WEST
WITH LITTLE TO NO COVERAGE WEST OF I-77. BY LATE AFTERNOON INTO
EVENING THE FLOW TURNS MORE EAST AND MODELS TURN SHOWERS MORE TO THE
SOUTHWEST ACROSS THE NC COUNTIES. ONCE THE SUN SETS...THINK SHOWERS
AND STORMS WEAKEN BUT ENOUGH CONVERGENCE ALONG DYING FRONT TO KEEP A
FEW SHOWERS AROUND TIL MIDNIGHT ACROSS THE NC COUNTIES/VA BORDER
COUNTIES. MODELS EVEN HINTING OF KEEPING A FEW SHOWERS AROUND THE
BLUE RIDGE INTO THU MORNING BUT GIVEN THE LACK OF COVERAGE THIS
MORNING THE THREAT SHOULD BE GONE AFTER MIDNIGHT.

AGAIN REALLY MOIST GROUND AND CLEARING IN PLACES WITH LIGHT/CALM WND
SHOULD LEAD TO THE DEVELOPMENT OF FOG.

TEMPS FORECASTED TO BE A LITTLE COOLER THAN MOS AS THE FLOW TURNS
NORTH. TRICKY GIVEN CLOUD COVER WHERE THERE WILL BE SOME PERIODS OF
SUNSHINE AND CLOUDS...ESPECIALLY ACROSS THE ERN CWA THIS AFTERNOON.
LOOKING AT HIGHS FROM THE MID TO UPPER 70S ACROSS THE WEST TO LOWER
80S SOUTHEAST.

TONIGHT...WILL BE COOLER BUT WET GROUND WILL KEEP IT FROM DROPPING
FURTHER SO LOOKING AT LOWS IN THE MID TO UPPER 50S WEST TO LOWER 60S
EAST.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 240 AM EDT WEDNESDAY...

SURFACE HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL CONTINUE TO
EXTEND INLAND THROUGH THE PERIOD AND GRADUALLY STRENGTHEN IN
RESPONSE TO BUILDING 5H HEIGHTS BY THE WEEKEND. 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 ESPCLY THU INTO THU NIGHT.
MODELS CONTINUE TO SHOW A LOW LEVEL CONVERGENCE ZONE ALONG THE
MOUNTAINS THU...THAT WILL GRADUALLY SHIFT WESTWARD FRIDAY IN
RESPONSE TO DRIER ADVECTION OUT EAST...AND MORE OF A NE WIND
COMPONENT DRIVEN BY POSSIBLE LOW PRESSURE OFF THE OUTER BANKS. ANY
ORGANIZED OR WIDESPREAD CONVECTION LIKELY HINDERED BY CONTINUED
DRYING ALOFT AS WELL AS WITH INCREASING SUBSIDENCE WITH LOW LEVEL
MOISTURE UNDERNEATH A WEAK INVERSION ALOFT. APPEARS BEST
DIURNALLY DRIVEN CHANCES THU AFTERNOON...SO RUNNING WITH LOW CHANCE
SCATTERED POPS WESTERN THIRD...THEN MORE ISOLATED COVERAGE MAINLY I-
77 CORRIDOR ON FRIDAY. OTRW MORE CLOUDS WEST EARLY THU WITH RANGE
FROM PC WEST TO MAINLY SUNNY EAST THU...AND AGAIN FRIDAY WHEN
SHOULD BE MORE SUN ALL SECTIONS.

LOW LEVEL DRYING SHOULD PUSH DEWPOINTS LOWER...AND MAKE FOR LOWER
HUMIDITY THROUGH THE PERIOD...WITH A GOOD DIURNAL SPREAD IN TEMPS
FROM THE UPR 70S-MID 80S FOR HIGHS...TO PLEASANT 50S/LOW 60S FOR
LOWS MOST NIGHTS.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 345 PM EDT TUESDAY...

MODERATING TEMPERATURES EXPECTED OVER THE WEEKEND AND INTO EARLY
NEXT WEEK AS THE UPPER LEVEL RIDGE CONTINUES TO BUILD...850 TEMPS
CREEPING TOWARD +2OC FOR MONDAY AND TUESDAY. THIS SUGGESTS SURFACE
TEMPS WILL TOP OUT MAINLY IN THE 80SF...TESTING 90F DEGREES FOR
THE URBAN AREAS. NO REAL FOCUS FOR DEEP CONVECTION DURING THE
PERIOD EXCEPT FOR CONVERGENCE OVER THE MTNS...SO KEPT ANY PRECIP
THREAT MAINLY DIURNAL AND PRIMARILY TARGETED TO THE MTNS.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 730 AM EDT WEDNESDAY...

MAINLY SEEING CIRRUS OVERHEAD WHILE FOG CREATES VSBY PROBLEMS AT
BLF/LWB AND BCB. FOG SHOULD LIFT BY 14-15Z AT ALL SITES.
VFR LATE THIS MORNING BEFORE THE FLOW SLOWLY TURNS MORE SE
ALLOWING BKN 4-6K FT CU CIGS TO REDEVELOP ESPCLY ALONG AND EAST OF
THE THE BLUE RIDGE. LATEST MODELS SUGGEST SOME LATE DAY SHRA/TSRA
POTENTIAL MAINLY KROA/KLYH/KDAN SO INCLUDING A VCTS THERE. OTRW
LEAVING OUT PRECIP MENTION GIVEN ISOLATED NATURE ELSW. LEFTOVER
CLOUDS AND WIDELY SCATTERED CONVECTION MAY LINGER INTO WEDNESDAY
NIGHT ALONG THE BLUE RIDGE CORRIDOR WITH MOST OF THIS COVERAGE
LIKELY ENDING UP SOUTH OF THE TERMINALS BEFORE ENDING LATER WED
NIGHT. MODELS PAINTING AGAIN AN EITHER/OR SCENARIO WITH
FOG/STRATUS LATE TONIGHT...AND CONFIDENCE HIGH ON SUB VFR AT MOST
SITES...BUT LOW ON WHETHER IT WILL BE STRATUS AND/OR FOG. FOR NOW
LEANING TOWARD MVFR CIGS WITH IFR VSBYS.

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