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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 191904
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
305 PM EDT SUN MAY 19 2013

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

&&

.NEAR TERM /THROUGH MONDAY NIGHT/...
-- Changed Discussion --
AS OF 300 PM SUNDAY...

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

OVERVIEW:
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/SHALLOW OUTFLOW BOUNDARIES
WILL PROVIDE A CONTINUOUS THREAT OF SHOWERS WITHIN AN AXIS OF
ANOMALOUSLY HIGH PWATS (PWATS 1.6-1.8")POOLING ATOP THE AREA.

REMAINDER OF THE AFTERNOON THROUGH TONIGHT:
THE WIDESPREAD SHOWERS AND THUNDERSTORMS HAVE COOLED TEMPERATURES
ACROSS THE AREA SIGNIFICANTLY...AND HAS LARGELY CONVECTIVELY
STABILIZED THE AIRMASS IN PLACE.  AS SUCH...THE MAIN SEVERE THREAT
THROUGH THE EARLY EVENING WILL BE FROM TRAINING SHOWERS AND
POTENTIAL MINOR FLOODING OF URBAN AND/OR POOR DRAINAGE AREAS.

HI-RES CAM MODELS SHOW A RAPID DROP OFF IN COVERAGE AS BOUNDARY
LAYER COOLS AND STABILIZES. LOWS TONIGHT AGAIN IN THE MID TO UPPER
60S.

MONDAY AND MONDAY NIGHT:
MUCH OF THE SAME ON MONDAY WITH A GRADUAL SHIFT OF THE DEEP MOISTURE
AND BEST CONVECTIVE COVERAGE ACROSS THE EASTERN HALF OF THE STATE.
EXTENSIVE CLOUD COVER AND EARLY START OF CONVECTION WILL CURB
SIGNIFICANT DESTABILIZATION...BUT LIKE TODAY EXPECT A DIURNAL
FLAREUP WITH A CONTINUED THREAT OF TRAINING STORM AND ASSOCIATED
MINOR FLOODING INTO THE AFTERNOON AND EVENING. HIGHS WILL AGAIN BE
DEPENDENT ON CLOUDS AND RADAR COVERAGE. HIGHS IN THE UPPER 70S TO
LOWER 80S. MORE LOW STRATUS AND FOG WILL BE LIKELY MONDAY NIGHT
AFTER THE SHOWERS DISSIPATE. LOWS IN THE MID TO UPPER 60S.
-- End Changed Discussion --


&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
-- Changed Discussion --
AS OF 245 PM SUNDAY...

THE MID/UPPER LEVEL WAVE (CAUSING ALL OF THE RAIN TODAY AND MONDAY)
WILL STILL BE LINGERING ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA ON TUESDAY...BEFORE FINALLY SHIFTING OFFSHORE TUESDAY NIGHT.
THEREFORE...SHOWER AND THUNDERSTORM CHANCES WILL REMAIN ELEVATED...
ALTHOUGH COVERAGE SHOULD BE LESS THAN PREVIOUS DAYS. THE HIGHEST
POPS ARE EXPECTED ACROSS THE EAST...AS THE WESTERN PORTIONS OF THE
FORECAST AREA MAY HAVE CONVECTIVE ACTIVITY MORE SUPPRESSED DUE TO
INCREASING SUBSIDENCE OF THE BACKSIDE OF TROUGH AXIS. HIGHS SHOULD
BE IN THE MID/UPPER 80S...WITH OVERNIGHT LOWS GENERALLY IN THE MID
60S.

SOME WEAK SHORTWAVE RIDGING WILL START TO BUILD OVER THE AREA BY
WEDNESDAY...WHILE AT THE SURFACE...THE BERMUDA HIGH WILL START TO
RIDGE WESTWARD INTO THE CAROLINAS. ALL OF THIS WILL TRANSLATE TO AN
EVEN FURTHER DECREASE IN PRECIP COVERAGE ON WEDNESDAY. HOWEVER...
SUFFICIENT MOISTURE WILL STILL BE IN PLACE OVER THE REGION...WITH
PWAT VALUES HOVERING NEAR 1.5 INCHES OR SO. THEREFORE...AM STILL
EXPECTING TO SEE WIDELY SCATTERED TO SCATTERED DIURNALLY DRIVEN
CONVECTION. HIGHS ONCE AGAIN SHOULD BE IN THE MID/UPPER 80S...WITH
OVERNIGHT LOWS IN THE MID/UPPER 60S.



.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 245 PM SUNDAY...

SHOWER AND THUNDERSTORM COVERAGE SHOULD BEGIN TO INCREASE ONCE AGAIN
BY THE END OF THE WEEK WITH THE APPROACH OF OUR NEXT MID/UPPER LEVEL
TROUGH AND ASSOCIATED COLD FRONT. THERE IS STILL SOME UNCERTAINTY
(MAINLY DUE TO RUN TO RUN INCONSISTENCIES) WITH THE TIMING OF THE
COLD FRONTAL PASSAGE...BUT OVERALL THE TREND HAS BEEN WITH A QUICKER
PASSAGE. IN FACT...THE MODELS ARE IN GENERAL AGREEMENT WITH BRINGING
THE FRONT THROUGH THE FORECAST AREA EARLY FRIDAY...ALMOST 12-18
HOURS EARLIER THAN WHAT MODELS INDICATED 24 HOURS AGO.
THEREFORE...WILL SHOW POPS HIGHEST POPS CONCENTRATED DURING THE
THURSDAY/EARLY FRIDAY TIME FRAME...THEN DECREASING FROM WEST TO EAST
THROUGHOUT THE DAY ON FRIDAY. AS OF NOW...IT NOW APPEARS THE WEEKEND
WILL BE DRY AS HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING FRONT.
WITH INCREASED PRECIP CHANCES/CLOUDS ON THURSDAY AND FRIDAY...TEMPS
WILL MOSTLY BE IN THE LOW/MID 80S...WITH SLIGHTLY COOLER TEMPS
EXPECTED FOR THE WEEKEND (GENERALLY IN THE 70S).
-- End Changed Discussion --



&&

.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
AS OF 205 PM SUNDAY...

WIDESPREAD SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING
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
RE-DEVELOPING.

SIMILAR CONDITIONS EXPECTED MONDAY WITH LIFR TO IFR MORNING CIGS...
 BECOMING VFR DURING THE LATE MORNING HOURS. SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS...ARE EXPECTED AGAIN MONDAY
AFTERNOON...WITH HIGHEST POPS/GREATEST COVERAGE IN THE EAST.

RAIN CHANCES WILL BEGIN TO DIMINISH BY TUESDAY AND ESPECIALLY INTO
WEDNESDAY WITH ONLY ISOLATED TO WIDELY SCATTERED SHOWERS/STORMS
EXPECTED. OTHERWISE...ASSOCIATED RESTRICTIONS IN MORNING STRATUS AND
FOG WILL CONTINUE THROUGH THURSDAY.

&&

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

&&

$$

SYNOPSIS...CBL
NEAR TERM...CBL
SHORT TERM...KRR
LONG TERM...KRR
AVIATION...CBL