-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 220606 CCA
AFDRNK

AREA FORECAST DISCUSSION...ISSUED BY WFO RALEIGH NC
NATIONAL WEATHER SERVICE BLACKSBURG VA
202 AM EDT WED MAY 22 2013

.SYNOPSIS...
AN UPPER LEVEL AREA OF LOW PRESSURE WILL DRIFT EAST AND OFFSHORE
OVERNIGHT. A LARGE LOW PRESSURE SYSTEM WILL TRACK FROM THE
CENTRAL PLAINS INTO THE GREAT LAKES BY THURSDAY. THIS SYSTEM WILL
PUSH A COLD FRONT THROUGH THE AREA THURSDAY...FOLLOWED BY HIGH
PRESSURE ON FRIDAY.
&&

.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 915 PM EDT TUESDAY...

BAND OF WEAKENING CONVECTION ASSOCIATED WITH OLD OUTFLOW BAND TO
THE WEST CONTINUES TO FADE ALONG THE WESTERN SLOPES ATTM WHILE NEW
OUTFLOW HAS GIVEN RISE TO ADDED SHRA/TSRA OVER THE WESTERN RIDGES.
LATEST MESO ANALYSIS SHOWS STILL ENOUGH INSTABILITY TO KEEP STORMS
GOING A WHILE LONGER MOUNTAINS WITH SOME OF THIS COVERAGE PERHAPS
DEVELOPING ACROSS THE BLUE RIDGE WHERE THE BEST LEFTOVER CAPES
EXIST. APPEARS THE OVERALL SEVERE THREAT SHOULD SLOWLY FADE PER
LOSS OF HEATING BUT LOW WET BULBS AND LOTS OF DRY AIR ALOFT OFF
EVENING SOUNDINGS STILL SUPPORT AT LEAST ISOLATED SEVERE POTENTIAL
THROUGH MIDNIGHT ESPCLY IF STORMS BECOME MORE LINEAR. THEREFORE
NUDGED UP POPS TO LOW LIKELYS FAR WEST OVER THE NEW FEW HOURS
WHILE KEEPING A SCATTERED NATURE FARTHER EAST DESPITE THE LACK OF
COVERAGE OFF THE LATEST HRRR SHORTLY AFTER MIDNIGHT. LOW LEVELS
ESPCLY EAST SHOW A BIT MORE DRYING THIS EVENING WITH SOME LIGHT
MIXING ONGOING WHICH SHOULD SLOW DOWN FOG FORMATION UNTIL LATE
EXCEPT WHERE RAINFALL HAS ALREADY OCCURRED. HOWEVER MOIST
DEWPOINTS WILL HOLD TEMPS MOSTLY IN THE MUGGY 60S WITH ONLY THE
DEEPER VALLEYS AND SPOTS SEEING SHOWERS PERHAPS FALLING INTO THE
50S LATE.

WARM AND HUMID CONDITIONS CONTINUE ON WEDNESDAY IN THE SOUTHERLY
FLOW OUT AHEAD OF THE APPROACHING COLD FRONT AND UPPER TROUGH.
INCREASED POPS FROM WEST TO EAST ON WEDNESDAY...WITH HIGHEST POPS
ALONG WESTERN MOUNTAINS. THE SWODY2 (DAY TWO CONVECTIVE OUTLOOK)
HAS THE SLIGHT RISK JUST TO OUR WEST ON WEDNESDAY. PLAYED HIGHS
TEMPERATURES COOLER ON WEDNESDAY WITH READINGS FROM THE MID 70S IN
THE MOUNTAINS TO THE MID 80S IN THE SOUTHEAST.
&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 255 PM EDT TUESDAY...

HAVE A COUPLE DAYS MORE OF HUMID WEATHER BEFORE FRONT SWINGS ACROSS
THURSDAY AND BRINGS A RETURN TO LOWER DEWPOINTS.

UNTIL THEN...NO MAJOR CHANGES TO THE FORECAST. WEDNESDAY NIGHT A
PIECE OF SHORTWAVE ENERGY ARRIVES ACROSS THE CENTRAL APPALACHIANS
WHICH CREATES AN AREA OF SHOWERS AND STORMS...MAINLY AFFECTING THE
WRN EDGE OF THE FORECAST AREA. THE BETTER PUSH OF THE FRONT ON
THURSDAY COMBINED WITH BETTER UPPER SUPPORT SHOULD BRING SOME
ENHANCED THREAT OF SHOWERS AND STORMS. TIMING OF THIS FRONT DOES
VARY SOMEWHAT FROM THE MODELS BUT ENOUGH AGREEMENT TO HAVE HIGH
CHANCE TO LIKLEY IN THE AREA THURSDAY. TIMING ALSO GIVES ISSUES TO
SVR THREAT. ATTM...EXPECT A LINE OF SHRA/TSRA TO BE IN THE MTNS IN
THE MORNING AND MOVING INTO THE PIEDMONT BY EARLY AFTERNOON. NOT
SEEING A LOT OF HEATING AS CLOUDS WILL BE GENEROUSLY SPREAD. ONE
AREA WITH THE BETTER INSOLATION COULD BE SOUTHSIDE VA/NW NC
PIEDMONT. AT THIS TIME...THE STORM PREDICTION CENTER HAS A 5 PERCENT
THREAT OF SVR WX MAINLY OVER THE PIEDMONT AND TIDEWATER AREAS OF
VA/NC.

THE FRONT WILL BE EAST OF THE AREA GOING INTO THURSDAY EVENING WITH
LINGERING SHORTWAVE INDUCED SHOWERS ACROSS THE MTNS OVERNIGHT. THE
MAIN SHORTWAVE SHIFTS EAST BY 12Z FRIDAY WITH DRIER AND COOLER AIR
ARRIVING. HIGHS FRIDAY WILL RANGE FROM THE LOWER TO MID 60S WEST TO
THE LOWER TO MID 70S EAST.
&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 130 PM EDT TUESDAY

FOR THE LONG RANGE FORECAST...THE MODELS KEEP A TROUGH IN PLACE
EARLY ON AND THEN GO MORE TOWARD A ZONAL TO RIDGE CONFIGURATION BY
THE END OF THE PERIOD.

WE SHOULD BE MAINLY DRY AS SFC HIGH BUILDS ACROSS THIS WEEKEND...SO
WEEKEND HOLIDAY PLANS ARE LOOKING GOOD FOR OUTDOOR ACTIVITIES AT
LEAST SATURDAY...AS THE LATEST ECMWF SHOWS ANOTHER WEAK SHORTWAVE
PUSHING ACROSS BY SUNDAY AND MAY BRING SOME SHOWERS ACROSS THE MTN
EMPIRE OF SW VA/INTO THE NC MTNS SUNDAY MORNING.

THE FLOW SWINGS MORE TOWARD THE SOUTHEAST SUNDAY EVENING INTO EARLY
NEXT WEEK WITH INCREASING HUMIDITY AND TEMPS. MODELS KEEPING MORE
ACTIVE WEATHER ACROSS THE OHIO VALLEY AND WEST...ALTHOUGH A WESTERLY
FLOW ALOFT CAN BRING STORMS WORKING EAST INTO THE MTNS. GIVEN WPC
SOLUTION OF THE ECMWF ENSEMBLE WILL KEEP THE FORECAST MORE ON THE
LOW CHANCE SIDE...BUT IF THE 12Z ECMWF VERIFIES WE COULD BE GETTING
SOAKED AGAIN MONDAY-WEDNESDAY.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 202 AM EDT WEDNESDAY...

THE MAIN CONCERN THIS MORNING APPEARS TO BE FOG AROUND AREAS THAT
HAD HEAVY RAINFALL RECENTLY. LATEST DATA SUGGESTS PATCHY FOG WITH
SOME AREAS OF LOCALLY DENSE FOG. IFR TO LIFR FOG WILL BE POSSIBLE.
THE EARLIER SHOWERS HAVE DISSIPATED. ONLY ISOLATED LIGHT RAIN
SHOWERS ARE EXPECTED THIS MORNING.

A QUICK IMPROVEMENT TO CONDITIONS WEDNESDAY MORNING WITH THE ONSET
OF HEATING AND DECENT MIXING BY MID OR LATE MORNING. THINK ALL SITES
WILL BE VFR BY 15Z/11AM BUT WITH A BETTER SHOT AT AFTERNOON
CONVECTION DEVELOPING ESPCLY WEST OF THE BLUE RIDGE BY 20Z/4PM. WITH
POTENTIAL TO SEE A BAND OF SHRA/TSRA DEVELOP WESTERN
SLOPES...INCLUDED A PREVAILING -TSRA THREAT AT BOTH KBLF/KLWB
WEDNESDAY AFTERNOON WHILE LEAVING ELSW VFR W/OUT CONVECTION UNDER
SCTD/BKN 5-6K FT CU FIELDS.

THE REGION STAYS IN A WARM...MOIST AIRMASS THROUGH THURSDAY AHEAD
OF A COLD FRONT THAT SHOULD PUSH THROUGH LATE IN THE DAY THURSDAY.
THIS WILL BRING THE BEST COVERAGE OF SHOWERS WEDNESDAY NIGHT INTO
THURSDAY ALONG WITH AREAS OF LATE NIGHT/EARLY MORNING FOG.

HIGH PRESSURE AND BETTER FLYING CONDITIONS ARE EXPECTED ON FRIDAY
AND THROUGH MUCH OF THE WEEKEND BEHIND THE FRONT.

&&

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

&&

$$
SYNOPSIS...AMS
NEAR TERM...AMS/JH/KK
SHORT TERM...WP
LONG TERM...WP
AVIATION.../WFORAH