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000
FXUS62 KRAH 190549
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
145 AM EDT WED JUN 19 2013

.SYNOPSIS...
COOLER HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTHEAST
THROUGH THE END OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 PM TUESDAY...

THE SEVERE WEATHER THREAT HAS ESSENTIALLY BEEN PUSHED EAST AND SOUTH
OF OUR REGION AS OF NOW. THE CONVECTIVE OUTFLOW BOUNDARIES HAVE
PUSHED THROUGH OF OUR REGION EXCEPT FOR EXTREME SOUTHERN SCOTLAND...
SAMPSON... AND SOUTHERN WAYNE COUNTIES. HOWEVER... THE CONVECTION
APPEARS MUCH MORE TAME THAN IN PREVIOUS HOURS. MAIN THREAT NOW
APPEARS TO BE LOCALLY HEAVY RAIN IN THE POSSIBLE TRAINING OF
CONVECTION (ESPECIALLY FROM ELLERBE AND LAURINBURG TO CLINTON). THIS
THREAT SHOULD SHIFT ON SOUTHWARD BY 1200 OR 100 AM. -BADGETT

MCV THAT TRACKED EAST ACROSS NORTHERN NORTH CAROLINA WAS LOCATED
OVER EASTERN HALIFAX COUNTY AS OF 840 PM. IT APPEARS THAT THERE WAS
JUST ENOUGH SHEAR ASSOCIATED ON THE LEADING FLANK OF THIS MESO-SCALE
FEATURE TO GEN UP SEVERAL ROTATING STORMS AND AT LEAST ONE TORNADO
TOUCHDOWN IN FRANKLIN COUNTY. THE LEADING CONVECTIVE LINE EXTENDED
FROM THE MCV WSW ACROSS WILSON... RALEIGH... SOUTHERN PINES TO NEAR
ALBEMARLE AT 840 PM. CURRENT SEVERE STORMS WERE LOCATED OVER WILSON
INTO NORTHERN WAYNE COUNTY WHERE DOPPLER RADAR INDICATED 50KT AT
3000 FEET WITH THE BOWING SEGMENT OVER THAT REGION. SOME OF THE
THESE WINDS MAY REACH THE GROUND. AREAS ALONG AND AHEAD OF THE
CONVECTIVE OUTFLOW BOUNDARY WILL BE MONITORED FOR ADDITIONAL SEVERE
WARNINGS. THE MAIN THREATS NOW APPEAR TO BE LOCALLY DAMAGING WIND
AND HEAVY RAINFALL. -BADGETT

OVERNIGHT...SFC COLD FRONT WILL PROGRESS SEWD AND SHOULD LIE WSW-ENE
ACROSS OUR FAR SOUTHERN-SE COUNTIES AT DAYBREAK. THIS FEATURE
SHOULD INTERACT WITH AVAILABLE MOISTURE TO TRIGGER SCATTERED SHOWERS
OVERNIGHT. STILL MUGGY OVERNIGHT THOUGH THE FAR N-NW SECTIONS MAY
START TO FEEL A LITTLE LESS HUMID BY DAYBREAK. MIN TEMPS MID 60S TO
NEAR 70.

&&

.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 250 PM TUESDAY...

STRONGER S/W IN THE NORTHERN STREAM WILL CROSS THE NORTHERN
MID ATLANTIC WHILE THE TAIL END OF THE SHEAR AXIS APPROACHES OUR
NORTHERN COUNTIES BY EARLY EVENING. NLY FLOW BEHIND THE INITIAL MID
LEVEL TROUGH WILL ADVECT DRIER AND SLIGHTLY MORE STABLE AIR INTO
CENTRAL NC. WHILE CLOUDS WILL LIKELY STICK AROUND DUE TO RESIDUAL
MOISTURE AND CYCLONIC CURVATURE IN THE MID LEVEL FLOW...CONVECTIVE
COVERAGE SHOULD BE LESS NUMEROUS WEDNESDAY AFTERNOON AND NOT AS
ROBUST. EXPECT TWO MAIN AREAS OF PRECIP...ONE OVER THE FAR SOUTH IN
VICINITY OF THE NEARLY STATIONARY SFC FRONT...AND THE OTHER OVER THE
FAR NORTH AHEAD OF THE SWD ADVANCING MID LEVEL SHEAR AXIS. PLAN TO
CAP POPS NO HIGHER THAN 50 PERCENT (NEAR SC BORDER) WITH A 1-IN-3
CHANCE ACROSS THE NORTH. AS ATMOSPHERE STABILIZES IN THE EARLY
EVENING...EXPECT MAJORITY OF THE CONVECTION TO DISSIPATE THOUGH A
STRAY SHOWER MAY STILL OCCUR IN VICINITY OF THE SHEAR AXIS ACROSS
THE NORTH. THIS SHEAR AXIS WILL CONTINUE TO PROGRESS SE OVERNIGHT
AND EXIT THE REGION BY DAYBREAK THU. SUBSIDENCE BEHIND THIS FEATURE
WILL AID TO DISSIPATE THE CLOUD COVERAGE AFTER MIDNIGHT.

EXPECT A FAIRLY UNIFORM TEMP FIELD WEDNESDAY DUE TO CLOUD COVERAGE
AND LOW LEVEL COLD AIR ADVECTION. MAX TEMPS NEAR 80 NORTH TO LOWER
80S SOUTH. MIN TEMPS WEDNESDAY NIGHT IN THE MID 60S.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 215 PM TUESDAY...

THURSDAY THROUGH FRIDAY...HEIGHTS ALOFT RISE OVER CENTRAL NORTH
CAROLINA...WITH A SUBSIDENT AIR MASS IN PLACE OVER THE AREA.
PRECIPITABLE WATER VALUES REMAIN HIGHER THURSDAY RELATIVE TO
FRIDAY...BETWEEN AN INCH AND 1.5 INCHES ON THE FORMER COMPARED TO A
DECREASE FROM THE NORTHEAST TO AT OR BELOW AN INCH FRIDAY. BOTH THE
GFS AND NAM BUFR SOUNDINGS...AND PARTICULARLY THE LATTER...FORECAST
ENOUGH MOISTURE AROUND 850MB THURSDAY FOR AREAS OF CU TO FORM...MORE
LIKELY TOWARD THE WESTERN PIEDMONT WHERE THE 850MB MOISTURE IS
HIGHEST. K INDICES FALL FROM THE NORTHEAST AS WELL THURSDAY
AFTERNOON CONTINUING INTO FRIDAY...WITH K INDICES WELL INTO NEGATIVE
VALUES BY FRIDAY AFTERNOON. IN TERMS OF DEEP CONVECTION...AMPLE
OVERALL CIN AND GRADUAL WARMING ALOFT WITH CONVERGENCE ALOFT SHOULD
PRECLUDE THAT. THERE SHOULD BE A FEW MORNING GUSTS WITH INITIAL
MIXING THURSDAY IN THE LOWER TO MID TEENS KTS IN THE MODESTLY TIGHT
GRADIENT BETWEEN AN INVERTED TROUGH OFF OF THE COAST AND SURFACE
HIGH PRESSURE BUILDING IN FROM THE NORTHWEST...BUT OVERALL 925MB
WINDS ARE MAINLY AROUND 10KT. 1000-850MB THICKNESSES SUGGEST HIGHS
IN THE LOWER TO MID 80S BOTH DAYS...CLOSE TO OR ON THE LOWER SIDE OF
MOS GUIDANCE. OVERNIGHT LOWS THURSDAY NIGHT AROUND 60 TO THE MID
60S...MINS POSSIBLY TEMPERED A LITTLE OVER THE SOUTHWEST PIEDMONT BY
SLIGHTLY GREATER UPPER-LEVEL MOISTURE FORECAST BY BOTH THE NAM AND
THE GFS.

FRIDAY NIGHT THROUGH TUESDAY...UPPER RIDGING CONTINUES TO BUILD IN.
AROUND THE RIDGE...THERE COULD BE A WEAK MID-LEVEL SHORTWAVE OR TWO
THAT ATTEMPTS TO MOVE...OR HAS SOME SUCCESS MOVING...INTO CENTRAL
NORTH CAROLINA ESPECIALLY LATE IN THE WEEKEND AND EARLY NEXT WEEK.
THE MOISTURE OF THE MEAN AIR MASS...AND MOISTURE AT THE
SURFACE...INCREASE SUNDAY INTO MONDAY...WITH SURFACE DEW POINTS
EXPECTED TO INCREASE TO AROUND 70F BY MONDAY...CONTINUING INTO
TUESDAY. WITH SURFACE RIDGING OVER THE GULF CURRENTLY FORECAST...IT
SHOULD BE A GRADUAL MOISTURE INCREASE ESPECIALLY AT THE
SURFACE...AND COARSE MODEL SOUNDINGS AT LEAST INTO SUNDAY AFTERNOON
HAVE A GOOD CONSENSUS OF AT LEAST BEING WEAKLY CAPPED ALOFT. WILL
MAINTAIN THE DRY FORECAST FRIDAY NIGHT THROUGH THE WEEKEND...BUT
WITH INCREASING MOISTURE...SOME GUIDANCE SUGGESTING A WEAKNESS IN
THE MID-LEVEL HEIGHTS TRANSLATING INTO COOLING ALOFT...AT LEAST SOME
QPF BY MUCH OF THE CURRENT LONG-TERM GUIDANCE...AND MEX MOS POPS
NEAR OR ABOVE CLIMATOLOGY...WILL INTRODUCE A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS AT THE END OF THE PERIOD MONDAY AND
TUESDAY. FORCING SHOULD BE LIMITED TO WEAK SURFACE TROUGHINESS...SEA
BREEZE...AND/OR WEAK MID-LEVEL PVA AT TIMES...WHICH MAY BE ENOUGH
FOR ISOLATED SHOWERS AND THUNDERSTORMS IN A RELATIVELY MOIST AIR
MASS. 1000-850MB THICKNESSES GRADUALLY RISE...WHICH...ALONG WITH MOS
GUIDANCE...WOULD SUGGEST HIGHS RISING TO AT OR ABOVE NORMAL BY
SUNDAY. IF THE SURFACE DEW POINT IS A LITTLE HIGHER THAN FORECAST
PRIMARILY DUE TO SLIGHTLY LESS MIXING...MAXIMUM AFTERNOON HEAT
INDICES COULD RISE TO AROUND 100 BY MONDAY.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 145 AM WEDNESDAY...

A LINE OF SHOWERS LINGERS ALONG THE SOUTHERN TIER OF THE AREA
AHEAD OF THE SURFACE COLD FRONT...WHICH HAS MOVED SOUTH OF ALL BUT
THE FAY TERMINAL. ENSUING DRYING IN NORTHERLY FLOW HAS EFFECTIVELY
CLEARED OUT IFR/LIFR CEILINGS OVER THE BULK OF THE AREA...AND TAFS
WILL SHOW AN IMPROVING TREND THROUGH THE REMAINDER OF THE
NIGHT...ALTHOUGH PATCHY MVFR CEILINGS AND VISIBILITY ARE POSSIBLE AT
TIMES...ESPECIALLY RDU/RWI/FAY... THROUGH AN HOUR OR SO AFTER
SUNRISE.

VFR CONDITIONS WILL BE PREVALENT BEYOND 12Z...ALTHOUGH A TRAILING
UPPER SHORT WAVE WILL BE SINKING SOUTH INTO THE AREA IN THE LATE
AFTERNOON. THIS SHORT WAVE WILL BE ACCOMPANIED BY BROKEN STRATOCU OR
ALTOCU...AND POSSIBLY SCATTERED SHOWERS ACROSS THE NORTHERN TIER
AFTER 21Z. CONDITIONS ARE NOT LIKELY TO FALL BELOW VFR ANYWHERE
EXCEPT POSSIBLY RDU AND RWI TOWARDS 00Z...AND WILL NOT INCLUDE THIS
POSSIBILITY DUE TO THE LOW PROBABILITIES AT THIS TIME.

LOOKING AHEAD: HIGH PRESSURE WILL BUILD INTO AND LINGER OVER CENTRAL
NC WEDNESDAY NIGHT THROUGH THE WEEKEND. THIS WEATHER SYSTEM WILL
BRING DRY AND STABLE CONDITIONS LEADING TO VFR PARAMETERS. THE
EXCEPTION WILL BE A BRIEF PERIOD OF MVFR VISIBILITY DUE TO
FOG...MAINLY IN THE COASTAL PLAIN.


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...BADGETT/WSS
SHORT TERM...WSS
LONG TERM...DJF
AVIATION...MLM