River Flood Warning 10, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
736 AM EDT SUN MAY 5 2013

.SYNOPSIS...
HIGH PRESSURE WILL SHIFT TO THE NORTHEAST ALLOWING INCREASING
ATLANTIC MOISTURE TO MOVE ACROSS THE SOUTH. A FRONT AND UPPER LEVEL
LOW PRESSURE SYSTEM WILL SLOWLY MOVE ACROSS THE SOUTHEAST PRODUCING
UNSETTLED WEATHER THROUGH THE EARLY PART OF THE WEEK. HIGH PRESSURE
WILL FILL IN BEHIND THE FRONT ON THURSDAY ALONG WITH MUCH WARMER
TEMPERATURES.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF DAYBREAK...WIDESPREAD PRECIP CONTINUES TO DEVELOP IN THE
UPSLOPE FLOW...BUT MAINLY TO THE WEST OF HIGHWAY 321. THE PRECIP
SHOULD CONTINUE TO GRADUALLY DEVELOP INTO THE CLT METRO AREA THROUGH
THE MORNING HOURS.

FOR TODAY AND TONIGHT...NOT SURE WHAT ELSE CAN BE SAID THAT HAS NOT
ALREADY BEEN BROUGHT TO LIGHT. THE MODEL GUIDANCE HOLDS NO BIG
SURPRISES. AN ATMOSPHERIC RIVER OF MOISTURE WILL BE POINTED TOWARD
THE WESTERN CAROLINAS FROM THE SOUTH AND SOUTHEAST THROUGH TONIGHT.
THE UPPER LOW WILL CONTINUE TO SLOWLY ROLL TOWARD THE WESTERN
CAROLINAS TODAY...BUT IS EXPECTED TO START TO MEANDER ACROSS THE SW
END OF THE APPALACHIANS TONIGHT. THE MOVEMENT OF THE UPPER LOW WILL
CAUSE THE DEEPER MOISTURE BAND TO PIVOT ACROSS THE REGION AND TAKE
ON A MORE SE TO NW ORIENTATION. THE MAIN LOW LEVEL MOISTURE FLUX
CONVERGENCE BAND WILL THEN TRANSLATE N ACROSS THE FCST AREA LATE
TODAY AND TONIGHT. THIS WILL BRING WAVE AFTER WAVE OF SHOWERS ACROSS
THE REGION. UPSLOPE ENHANCEMENT WILL FOCUS THE HIGHER PRECIP AMOUNTS
IN THE VICINITY OF THE BLUE RIDGE. THIS LOOKS LIKE THE TYPE OF EVENT
WHERE THE WATER WILL GRADUALLY FILL UP CREEKS AND STREAMS AND THEN A
HEAVIER BURST WILL COME ALONG TO PUSH THEM INTO FLOOD. FOLLOWED HPC
GUIDANCE ON THE QPF. THAT SAID...NOT SEEING A GOOD REASON TO EXPAND
THE FLOOD WATCH INTO THE PIEDMONT AT THIS TIME...SO WE WILL LET IT
RIDE. HIGH TEMPS WILL REMAIN WELL BELOW NORMAL WITH THE EXTENSIVE
CLOUDINESS AND PRECIP.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AT 250 AM EST SUNDAY...A DEEP...ANOMALOUS CLOSED UPPER LOW WILL BE
OVER AL ON SUNDAY EVENING. THIS LOW MOVES INTO NW GA BY MID DAY
MONDAY... THEN DRIFT SLOWLY SOUTH INTO CENTRAL GA EARLY MONDAY
NIGHT. THE LOW MOVES EAST OVER CENTRAL SC MID DAY TUESDAY AND TO THE
FAYETTEVILLE NC AREA LATE TUESDAY NIGHT. ITS INFLUENCE ON OUR
WEATHER GRADUALLY DECREASES IN MID WEEK.

AN OCCLUDED SURFACE FRONT ASSOCIATED WITH THE UPPER LOW WILL
CONTINUE MOVING SLOWLY NE ACROSS THE WESTERN CAROLINAS ON MONDAY.
STRONG MOIST UPSLOPE FLOW AND ISENTROPIC UPGLIDE WILL PRECEDE THE
FRONT INTO THE EAST FACING NC BLUE RIDGE...SUPPORTING HEAVY RAINFALL
THERE THROUGH MONDAY NIGHT. MODEST INSTABILITY WILL ACCOMPANY THE
FRONT MAINLY MOVING NORTH ACROSS THE CHARLOTTE METRO AREA AND POINTS
EAST. SOME AMOUNT OF INSTABILITY IS EXPECTED TO REMAIN IN THE
CHARLOTTE AREA OVERNIGHT MONDAY NIGHT AS THE UPPER LOW LINGERS WITH
STEEP LAPSE RATES. THE INSTABILITY WILL INCREASE AGAIN WITH DAY TIME
HEATING ON TUESDAY.

MOISTURE IS EXPECTED TO WRAP AROUND THE LOW FROM THE NORTH LATE
TUESDAY WITH THE LOW MOVING EAST OF OUR AREA.

TEMPERATURES WILL REMAIN BELOW NORMAL AS THE UPPER LOW IS NEARBY AND
THEN WARM TO NEAR OR ABOVE NORMAL THURSDAY THROUGH SATURDAY.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AT 310 AM EST SUNDAY...THE CLOSED UPPER LOW WILL BE OVER EASTERN NC
WEDNESDAY AND OVER NORFOLK VA BY LATE WED NIGHT. WEAK SURFACE HIGH
PRESSURE AND A SHALLOW UPPER RIDGE WILL MOVE IN FROM THE WEST TO
REPLACE THE PERSISTENT UPPER LOW. SOME WRAP AROUND MOISTURE WILL
COME DOWN FROM THE NORTH ON THE WEST SIDE OF THE UPPER LOW WEDNESDAY
SUPPORTING SOME SHOWERS AND INSTABILITY WILL BE LIMITED SO NOT MUCH
IF ANY THUNDER. AT LEAST TEMPERATURES WILL RETURN TO 60S MTNS AND
LOW TO MID 70S FOOTHILLS AND PIEDMONT ON WEDNESDAY. DOWNSLOPE FLOW
ON THURSDAY WILL PRODUCE AT LEAST SEASONAL NORMAL TEMPERATURES ON
THURSDAY. MOISTURE ON THURSDAY VERY LIMITED AND ONLY FOR THE NC MTNS
WITH SLIGHT POPS.

THE NEXT SYSTEM APPROACHES AT THE END OF THE WEEK. THE PREVIOUS
ECMWF WAS MUCH MORE PROGRESSIVE PUSHING THIS SHORTWAVE EAST OF OUR
AREA BY LATE SATURDAY. THE NEWEST RUN OF THE ECMWF IS MORE GFS LIKE
WHICH PRODUCES SCATTERED SHOWERS AND STORMS LATE FRIDAY AND THE
TREND INCREASES ON SATURDAY AS THE SURFACE FRONT GETS CLOSER.
TEMPERATURES MAY REACH 80 IN THE PIEDMONT THURSDAY BUT CERTAINLY
POSSIBLE FRIDAY AND SATURDAY.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AT KCLT...KEPT MVFR FOR THE FIRST SEVERAL HOURS. THINK IT WILL TAKE
THE EWD MOVEMENT OF THE STEADIER PRECIP INTO THE SRN PIEDMONT TO
BRING THE IFR CEILING ACROSS THE AIRFIELD. EXPECT CEILING TO FALL
INTO IFR CATEGORY BY 17Z AT THE LATEST...PERHAPS ON A TEMPORARY
BASIS BY MID MORNING. ONCE THERE...THE IFR SHOULD PREVAIL THROUGH
THE END OF THE PERIOD. PRECIP WILL COME IN WAVES OVER THE NEXT 24
HOURS. THIS COULD BRING BOUTS OF IFR VISIBILITY IN HEAVIER
SHOWERS...BUT FOR NOW WILL HANDLE THE IFR ONLY WITH THE CEILING.
WINDS WILL REMAIN ENE AND GUSTY THROUGH THE DAY. A SHIFT TO ESE IS
LIKELY AS THE LOW MOVES CLOSER AND VEERS THE LOW LEVEL FLOW THIS
EVENING.

ELSEWHERE...SIMILAR TO KCLT EXCEPT THAT PRECIP HAS ALREADY MOVED
IN...SO IFR CONDITIONS WILL EXPAND ACROSS THE REGION IF THEY HAVE
NOT ALREADY.

OUTLOOK...THE WEATHER WILL BE UNSETTLED THRU MID WEEK AS A SLOW
MOVING AREA OF LOW PRESSURE AFFECTS THE SOUTHEAST.  WIDESPREAD
MVFR/IFR RESTRICTIONS ARE LIKELY THROUGH MONDAY MORNING.
RESTRICTIONS WILL BECOME MORE SPOTTY FROM MONDAY ONWARD.

CONFIDENCE TABLE...

            11-17Z        17-23Z        23-05Z        05-11Z
KCLT       HIGH  98%     LOW   34%     MED   68%     HIGH  95%
KGSP       MED   74%     HIGH  90%     HIGH  87%     HIGH  93%
KAVL       HIGH 100%     HIGH  97%     HIGH  97%     HIGH 100%
KHKY       HIGH  85%     LOW   41%     HIGH  87%     HIGH  85%
KGMU       HIGH  80%     HIGH  85%     MED   78%     HIGH  88%
KAND       HIGH  91%     HIGH  85%     MED   77%     MED   76%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLOOD WATCH THROUGH LATE TONIGHT FOR GAZ010-017-018-026-028-
     029.
NC...FLOOD WATCH FROM NOON EDT TODAY THROUGH MONDAY EVENING FOR
     NCZ033-035-049-050-056-068-069-501>508.
     FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ048-051>053-058-059-
     062>065-509-510.
SC...FLOOD WATCH THROUGH LATE TONIGHT FOR SCZ001>007-010-011.

&&

SYNOPSIS...DEO
NEAR TERM...PM
SHORT TERM...DEO
LONG TERM...DEO
AVIATION...PM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
500 AM EDT SUN MAY 5 2013

NCZ033-035-049-050-056-068-069-501>508-060900-
AVERY-ALEXANDER-YANCEY-MITCHELL-CATAWBA-CLEVELAND-LINCOLN-
CALDWELL MOUNTAINS-GREATER CALDWELL-BURKE MOUNTAINS-GREATER BURKE-
MCDOWELL MOUNTAINS-EASTERN MCDOWELL-RUTHERFORD MOUNTAINS-
GREATER RUTHERFORD-
500 AM EDT SUN MAY 5 2013

...FLOOD WATCH IN EFFECT FROM NOON EDT TODAY THROUGH MONDAY
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PIEDMONT NORTH CAROLINA AND
WESTERN NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLOOD WATCH.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLOOD WATCH.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF FLOODING
TO OUR OFFICE.

GAZ010-017-018-026-028-029-NCZ048-051>053-058-059-062>065-509-510-
SCZ001>007-010-011-060900-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-MADISON-SWAIN-HAYWOOD-
BUNCOMBE-GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-
HENDERSON-POLK MOUNTAINS-EASTERN POLK-OCONEE MOUNTAINS-
PICKENS MOUNTAINS-GREENVILLE MOUNTAINS-GREATER OCONEE-
GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-ANDERSON-ABBEVILLE-
500 AM EDT SUN MAY 5 2013

...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...WESTERN
NORTH CAROLINA AND UPSTATE SOUTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLOOD WATCH.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF FLOODING
TO OUR OFFICE.

NCZ036-037-057-070>072-082-SCZ008-009-012>014-019-060900-
IREDELL-DAVIE-ROWAN-GASTON-MECKLENBURG-CABARRUS-UNION NC-CHEROKEE-
YORK-LAURENS-UNION SC-CHESTER-GREENWOOD-
500 AM EDT SUN MAY 5 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PIEDMONT NORTH CAROLINA AND
UPSTATE SOUTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

A SLOW MOVING UPPER LEVEL LOW AND AN ASSOCIATED COLD FRONT WILL
SLOWLY APPROACH THE CAROLINA PIEDMONT FROM THE WEST TODAY THROUGH
MONDAY. HEAVY RAINFALL WILL BE POSSIBLE AHEAD OF THE FRONT...
MAINLY TODAY AND TONIGHT. IT IS POSSIBLE THAT AROUND 2 INCHES OF
RAINFALL COULD OCCUR IN THE PIEDMONT OF THE CAROLINAS BEFORE THE
RAIN DECREASES IN COVERAGE AND INTENSITY LATE MONDAY AS THE
HEAVIER RAIN MOVES NORTH OF INTERSTATE 40. IF HEAVY RAIN PERSISTS
AT ANY LOCATION...ESPECIALLY IN URBAN AREAS...FLOODING COULD DEVELOP.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

THE HEAVY RAINFALL WILL MOVE NORTH OF INTERSTATE 40 LATE MONDAY
AFTERNOON. SOME LOCATIONS IN THE CAROLINA PIEDMONT MAY HAVE
RAINFALL TOTALS OF AROUND TWO INCHES FROM THIS EVENT.
THUNDERSTORMS MAY ALSO DEVELOP IN THE CAROLINA PIEDMONT MONDAY
AFTERNOON WHICH WOULD ENHANCE RAINFALL INTENSITY AND THIS COULD
RESULT IN FLOODING...ESPECIALLY IF THIS OCCURS IN AN URBAN AREA.

.SPOTTER INFORMATION STATEMENT...

NONE.

DEO