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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 191419
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1019 AM EDT SUN MAY 19 2013

.SYNOPSIS...
-- Changed Discussion --
DAMPENING MID-LEVEL TROUGH WILL MOVE SLOWLY EASTWARD INTO THE
CAROLINAS TONIGHT...AND WILL LINGER OVER THE AREA THROUGH TUESDAY.
-- End Changed Discussion --

&&

.NEAR TERM /TODAY AND TONIGHT/...
-- Changed Discussion --
AS OF 1019 AM SUNDAY...

...LOCALLY HEAVY RAIN POSSIBLE THROUGH MONDAY...

DAMPENING MID-LEVEL TROUGH WILL MOVE SLOWLY EASTWARD INTO THE
CAROLINAS BY TONIGHT...AND WILL LINGER OVER THE AREA THROUGH
TUESDAY. INDIVIDUAL SHORTWAVE VORT DISTURBANCES ROTATING EASTWARD
ACROSS THE AREA COUPLED WITH WEAK SFC BOUNDARIES FROM OVERNIGHT
STORMS WILL PROVIDE A CONTINUOUS THREAT OF SHOWERS WITHIN AN AXIS OF
ANOMALOUSLY HIGH PWATS (PWATS 1.6-1.8")POOLING ATOP THE AREA.

WHILE EXTENSIVE CLOUD COVER WILL MODULATE DAYTIME HEATING...WEAK TO
MODERATE INSTABILITY OF 500 TO 1000 J/KG IS STILL EXPECTED TO
DEVELOP...AND WILL RESULT IN DIURNAL FLAREUPS IN CONVECTION. WEAK
SHEAR OF 15 KTS OF LESS WILL YIELD A LOW-END/ISOLATED PULSE SEVERE
THREAT. HOWEVER... CLUSTERS OF SLOW MOVING AND TRAINING SHOWERS AND
THUNDERSTORMS MAY RESULT IN SOME MINOR FLOODING. THE HEAVY
RAIN/MINOR FLOODING THREAT WILL BE MONITORED IN INSTANCES OF
TRAINING CELLS OVER URBAN OR POOR DRAINAGE AREAS.

LOOK FOR THE HIGHEST POPS TO SLOWLY SPREAD EAST AND NORTH THROUGH
THE AFTERNOON AND EVENING. HIGHS TODAY WILL BE DEPENDENT
ON TIMING OF CONVECTION WITH CURRENT RADAR TRENDS SHOWING
AN EARLY ARRIVAL OF STORMS ACROSS THE SOUTH AND WEST.
HIGHS RANGING FROM LOWER TO MID 70S NW TO LOWER 80S SOUTHEAST.

LOWS TONIGHT SHOULD AGAIN BE IN THE MID TO UPPER 60S.
-- End Changed Discussion --


&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
AS OF 230 AM SUNDAY...

A GRADUAL SHIFT OF THE DEEP MOISTURE TO THE EASTERN ZONES IS
ANTICIPATED MONDAY. THE MID/UPPER TROUGH IS FORECAST TO WEAKEN BUT
STILL LINGER OVER THE REGION ON MONDAY. WE SHOULD SEE ANOTHER DAY OF
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS... MAINLY IN THE
CENTRAL AND EASTERN ZONES... AND MAINLY DURING THE AFTERNOON AND
EVENING HOURS.

DEEP LAYER MOISTURE ON THE ORDER OF 1.75 TO 2 INCHES WILL SHIFT TO
THE COASTAL PLAIN WITH NOTABLE DRYING IN THE MOUNTAINS. LOCALLY
HEAVY RAIN CAN AGAIN OCCUR... ESPECIALLY FROM THE EASTERN PIEDMONT
TO THE COAST. QPF OF 0.25 TO 0.50 WILL BE FORECAST WITH LOCALLY 1.5
INCHES IN THE COASTAL PLAIN. HIGHS WILL AGAIN BE TEMPERED BY THE
CLOUDS/MOISTURE WITH READINGS MOSTLY 78-84.

MORE LOW STRATUS AND FOG WILL BE LIKELY MONDAY NIGHT AFTER THE
SHOWERS MOSTLY DISSIPATE. LOWS IN THE MID TO UPPER 60S.
&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 256 AM SUNDAY...

THE UPPER LEVEL WAVE WILL MOVE ACROSS THE AREA ON TUESDAY... WITH
PWATS 1.5" OR GREATER OVER THE AREA. SUFFICIENT INSTABILITY... WITH
WEAK SHEAR... WILL SUPPORT DEVELOPMENT OF GENERAL PULSE
THUNDERSTORMS... POTENTIALLY SEA BREEZE ENHANCED LATE IN THE DAY.
HIGHS IN THE MID 80S.

WHILE A WEAK UPPER LEVEL RIDGE BUILDS IN BRIEFLY ON WEDNESDAY...
MOISTURE STILL REMAINS HIGH OVER THE AREA... CONTINUING TO SUPPORT
THUNDERSTORM DEVELOPMENT MAINLY DURING THE AFTERNOON AND EVENING
HOURS WEDNESDAY AND THURSDAY... AND SOUTHERLY FLOW WILL KEEP HIGHS
NEAR TO SLIGHTLY ABOVE NORMAL IN THE LOW TO MID 80S... AND LOWS IN
THE MID 60S TO NEAR 70. A TROUGH OVER THE PLAINS STATES ON WEDNESDAY
WILL BEGIN TO MOVE EASTWARD... REACHING OUR AREA AT THE END OF THE
WEEK. THE ASSOCIATED COLD FRONT LOOKS TO DIP IN TO THE REGION LATE
WEEK. THE GFS HAS REMAINED SLOWER WITH THE FRONT THE LAST FEW
RUNS... DEVELOPING A LOW PRESSURE AREA AND MOVING IT ALONG THE
ATLANTIC COAST... AND DELAYING THE FRONTAL PASSAGE UNTIL SATURDAY.
AT THIS POINT... ENSEMBLE MEANS DO NOT SUPPORT THIS SOLUTION. THE
ECMWF IS FASTER AND BRINGS THE FRONT THROUGH FRIDAY. WILL CONTINUE
CHANCE POPS ON FRIDAY... TAPERING TO SLIGHT CHANCE SATURDAY.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 745 AM SUNDAY...

IFR TO LIFR CIGS WILL SLOWLY LIFT TO MVFR ACROSS THE WESTERN AND
CENTRAL PIEDMONT LATE THIS MORNING. MEANWHILE...EASTERN TERMINALS
(KFAY AND KRWI) SHOULD HOLD AT VFR. SCATTERED SHOWERS THIS MORNING
WILL BECOME MORE WIDESPREAD THIS AFTERNOON AND EVENING WITH A THREAT
OF THUNDER AT ALL TAF SITES....WITH PERIODS OF IFR TO LIFR
RESTRICTIONS IN HEAVY SHOWERS AND ISOLATED THUNDERSTORMS POSSIBLE.
THE CHANCE FOR SHOWERS WILL CONTINUE OVERNIGHT WITH WIDESPREAD IFR
TO MVFR CEILINGS DEVELOPING.

SIMILAR CONDITIONS EXPECTED MONDAY WITH LIFR TO IFR MORNING CIGS...
BECOMING MVFR DURING THE DAY. SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS... ESPECIALLY DURING THE AFTERNOON AND EVENING.

DRIER CONDITIONS ARE FORECAST TUESDAY INTO WEDNESDAY WITH MORNING
STRATUS... FOG... IFR TO LIFR CIGS/VSBYS BECOMING VFR DURING THE
DAY. WIDELY SCATTERED SHOWERS/STORMS DURING THE AFTERNOON TUESDAY.
ONLY ISOLATED SHOWERS BY WEDNESDAY AFTERNOON.

&&

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

&&

$$

SYNOPSIS...CBL
NEAR TERM...CBL
SHORT TERM...BADGETT
LONG TERM...SEC
AVIATION...CBL/STRICKLER