660
FXUS62 KRAH 111738
AFDRAH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
137 PM EDT SUN MAY 11 2025
SYNOPSIS
A SLOW MOVING UPPER LOW CENTERED OVER THE LOWER MISSISSIPPI
RIVER VALLEY WILL DRIFT NORTHEAST THROUGH THE MID SOUTH TO THE
CENTRAL APPALACHIANS THROUGH WEDNESDAY, BRINGING WET AND UNSETTLED
WEATHER TO THE REGION.
NEAR TERM /TODAY THROUGH TONIGHT/
AS OF 1040 AM SUNDAY...
AN OLD MCV WAS LOCATED OVER THE WESTERN PIEDMONT LATE THIS MORNING.
SHOWERS CONTINUED OVER NC IN AN ARC LOCATED FROM NEAR BOONE AND
HICKORY SE TO WILMINGTON. THIS ARC OF SHOWERS CONTINUED TO WEAKEN AS
IT MOVES NE INTO THE DRIER AIR OVER NORTHERN AND NORTHEASTERN NC AND
VA. EXPECT THIS WEAKENING TREND TO CONTINUE; HOWEVER, THE SHOWERS
SHOULD HOLD TOGETHER LONG ENOUGH FOR HIGH POP LATE MORNING AND EARLY
AFTERNOON FOR THE TRIAD TO THE TRIANGLE TO ROCKY MOUNT, WITH QPF
GENERALLY AROUND 0.1 TO 0.25. HIGHS THIS AFTERNOON WILL LARGELY BE
INFLUENCED BY SHOWERS AND EXTENSIVE CLOUDINESS. EXPECT MOSTLY
UPPER 60S TO LOWER 70S.
A LULL IN THE RAIN IS EXPECTED ACROSS MUCH OF CENTRAL NC THIS
EVENING AND EARLY OVERNIGHT BEFORE THE NEXT ROUND OF MORE VIGOROUS
SHOWERS/ISOLATED THUNDERSTORMS ARRIVES FROM THE SOUTH DURING
THE PRE-DAWN HOURS MONDAY MORNING ASSOCIATED WITH A POWERFUL JET
STREAK LIFTING NORTH ON THE DOWNWIND SIDE OF THE UPPER TROUGH. LOWS
TONIGHT IN THE UPPER 50S TO LOWER 60S.
SHORT TERM /MONDAY AND MONDAY NIGHT/
AS OF 300 AM SUNDAY...
* A FLASH FLOOD WATCH HAS BEEN ISSUED FOR ALL OF CENTRAL NC FROM
EARLY-MORNING MON THROUGH DAYBREAK TUE, DUE TO THE POTENTIAL FOR
ROUNDS OF MODERATE TO HEAVY RAIN.
LITTLE HAS CHANGED WITH THE OVERALL PATTERN AND EXPECTATIONS FROM
EARLIER FORECASTS. THE DEEP LOW CENTERED OVER LA/MS EARLY MON IS
EXPECTED TO OPEN A BIT AND LIFT NNE INTO W TN/W KY THROUGH EARLY
TUE, AS THE TRAILING NEGATIVELY TILTED MID LEVEL TROUGH AND SURFACE
FRONT LIFT NE THROUGH GA AND THE WESTERN CAROLINAS. THE COMBINATION
OF DEEP AND PLENTIFUL MOISTURE AND ROUNDS OF FORCING FOR ASCENT
CONTINUE TO FAVOR A RISK FOR AREAS OF HEAVY RAIN TOTALS. THESE
INGREDIENTS INCLUDE A PLUME OF 1.5-1.8" PWS (~160% OF NORMAL) THAT
WILL SPREAD NORTHWARD ON THE E SIDE OF THE LOW THROUGH CENTRAL NC
STARTING LATE TONIGHT, SHIFTING INTO E NC LATE MON NIGHT, WITHIN A
LONG LOW-LEVEL SE FETCH OF ATLANTIC MOISTURE ON THE SW SIDE OF THE
EXITING HIGH, AND WITH CONTRIBUTIONS FROM GULF-SOURCE MOISTURE IN
MORE SOUTHERLY FLOW JUST ALOFT. WARM RAIN PROCESSES ARE FAVORED,
WITH PROJECTED LCL-0C DEPTH OF 11K-12K FT AMIDST A STREAM OF
ELEVATED INTEGRATED VAPOR TRANSPORT. WHILE IT WON'T BE RAINING
HEAVILY ALL OF THIS TIME, THERE MAY BE AT LEAST TWO MAIN WINDOWS OF
GREATER POTENTIAL WHERE FORCING WILL BE FOCUSED, INCLUDING EARLY MON
MORNING DUE TO A SURGE IN DEEP MOIST ISENTROPIC UPGLIDE, AND MON
EVENING/NIGHT DUE TO AN INCREASE IN UPPER DIVERGENCE IN THE EXIT
REGION OF THE SOUTHERLY UPPER JET. FORECAST TOTAL RAINFALL FROM
TODAY THROUGH MON NIGHT HAS ACTUALLY RISEN A BIT SINCE YESTERDAY,
WHICH COULD BE A RESPONSE TO DATA ASSIMILATION OF CURRENT RAINFALL
TO OUR S AND/OR INCLUSION OF RAINFALL FROM CONVECTION-ALLOWING
MODELS, AS WE'RE STARTING TO GET WITHIN THEIR TIME FRAME. THE LATEST
WPC SUPERENSEMBLE QPF PLUMES ARE OVERALL AROUND 1/2 INCH HIGHER WITH
TOTAL QPF THAN YESTERDAY'S OUTPUT. WE'RE MOST LIKELY TO SEE 2-4
INCHES OF RAIN THROUGH EARLY TUE, ALTHOUGH THE LATEST ENSEMBLE
PROBABILITIES GIVE A 10% CHANCE OF UP TO 5 INCHES IN SPOTS. THIS
COULD PRODUCE LOCALIZED FLOODING, ESP IN URBAN AREAS, WITH RISES ON
CREEKS AND STREAMS POSSIBLE, ALL SUPPORTING THE FLASH FLOOD WATCH
ISSUANCE. WITH ABUNDANT THICK CLOUDS AND MINIMAL INSOLATION, EXPECT
A TIGHTER DIURNAL TEMP RANGE, WITH HIGHS IN THE UPPER 60S TO MID 70S
FOLLOWED BY LOWS IN THE 60S. -GIH
LONG TERM /TUESDAY THROUGH SATURDAY/
AS OF 410 AM SUNDAY...
* POCKETS OF HEAVY RAIN WILL REMAIN POSSIBLE INTO TUE, ALONG WITH A
FEW STRONG STORMS.
* HOT WEATHER IS EXPECTED LATE WEEK.
TUE-TUE NIGHT: THE SLOW-MOVING MID LEVEL LOW WILL CONTINUE TO OPEN
AS IT TRACKS E/NE INTO WV, WHILE ITS TRAILING TROUGH AND SURFACE
FRONT PUSH FURTHER ENE INTO THE CAROLINAS, NUDGING THE PLUME OF
GREATEST AND MOST ANOMALOUS PW INTO OUR NE CWA AND EVENTUALLY TO OUR
NE AND OFF THE MID ATLANTIC COAST. IF HEAVY AND/OR TRAINING
RAINBANDS PERSIST OVER OUR NE TUE MORNING, A SHORT-TERM EXTENSION OF
THE FLASH FLOOD WATCH MAY BE NEEDED. BUT OVERALL, WE SHOULD SEE A
DECREASE IN HEAVY RAIN CHANCES WITH LOWERING PW AND WANING DYNAMIC
FORCING FOR ASCENT WITH WEAKENING MID LEVEL FLOW WITHIN THE
APPROACHING INCREASINGLY BAGGY TROUGH. PWS WILL STILL BE ABOVE
NORMAL, THOUGH, AND MODELS PROJECT MODERATE CAPE OF 1000-2000 J/KG
IN THE AFTERNOON WITH 25-35 KT OF DEEP LAYER BULK SHEAR AMIDST
DECENT LOW AND MID LEVEL LAPSE RATES, SO WILL MAINTAIN HIGH POPS,
MAINLY NE EARLY AND AREAWIDE LATE IN THE DAY, TAPERING DOWN TUE
EVENING/NIGHT. EXPECT HIGHS IN THE MID 70S TO NEAR 80, ALTHOUGH IF
CLOUD COVER IS MORE EXTENSIVE THAN EXPECTED, THESE HIGHS MAY BE
OPTIMISTIC. LOWS IN THE UPPER 50S TO LOW 60S.
WED-SAT: RAIN CHANCES WILL REMAIN HIGH ESP ACROSS OUR N AND E WED,
AS THE NEGATIVELY TILTED TROUGH LIFTS UP THROUGH THE AREA, ALTHOUGH
THE STEADY DECLINE IN MID LEVEL WIND SPEEDS WILL RESULT IN WANING
DPVA OVERALL. HIGH TEMPS WILL REMAIN SOMEWHAT REDUCED BY CLOUDS AND
SHOWERS, DESPITE SLOWLY REBOUNDING THICKNESSES, SO EXPECT HIGHS IN
THE UPPER 70S TO LOW 80S. BY THU, A DEEP LOW TRACKING THROUGH THE
ROCKIES AND DAKOTAS INTO THE UPPER MIDWEST WILL FORCE DOWNSTREAM
RIDGING TO BUILD INTO THE CAROLINAS FROM THE WSW, AND AS WE GET INTO
THE WARM SECTOR, OUR THICKNESSES WILL RISE TO 10 M ABOVE NORMAL THU.
BY FRI/SAT, AS THIS LOW SHEARS W-E AND SHIFTS SLOWLY E/ESE OVER S
ONTARIO, IT WILL TAMP DOWN THE RIDGE RESULTING IN A FAST W TO WNW
STEERING FLOW OVER THE E-CENTRAL CONUS, WITH A SHARPENING W-E
SURFACE FRONTAL ZONE TO OUR N FROM THE MID MISS VALLEY ACROSS THE
MID ATLANTIC. SUCH A PATTERN FAVORS THE POTENTIAL FOR MIDWEST MCS
ACTIVITY (OR ITS RESIDUAL CLOUDS AND MCV) TO PASS THROUGH OUR
REGION, SO WILL NEED TO MONITOR FOR THIS POSSIBILITY AS WE GET LATER
IN THE WEEK. AND PRIOR TO THIS, THE GFS PROJECTS HIGH CAPE OF 2000-
3000 J/KG AND 35-40 KT OF MID LEVEL FLOW, WHICH COULD SUPPORT
ORGANIZED STRONG LATE-DAY STORMS. FOR NOW, WILL CARRY LOW END
DIURNAL-LEANING POPS THU AND FRI, THEN A BIT HIGHER (NEAR CLIMO) FOR
SAT. WITH THICKNESSES 25 M ABOVE NORMAL FRI/SAT AND SURFACE
DEWPOINTS RISING TO NEAR OR OVER 70F, THE RESULTANT HEAT MAY BE A
HEALTH CONCERN, WITH THE EXPERIMENTAL HEAT RISK VALUES SUGGESTING AN
ELEVATED HEAT ILLNESS THREAT, AS HEAT INDICES MAY REACH 95-100F, ESP
FRI. EXPECT HIGHS IN THE 80S THU, UPPER 80S TO MID 90S FRI, AND MID
80S TO LOW 90S SAT WITH THE POTENTIAL FOR MORE CLOUDS AND BETTER
CONVECTION CHANCES. -GIH
AVIATION /18Z SUNDAY THROUGH THURSDAY/
AS OF 137 PM SUNDAY...
THROUGH 18Z MONDAY: GENERALLY MVFR TO VFR CONDITIONS ARE EXPECTED
THIS AFTERNOON WITH SOME SPOTTY SHOWERS. CONDITIONS WILL SLOWLY
DETERIORATE THIS EVENING AND OVERNIGHT AS IFR CIGS DEVELOP ALONG
WITH SOME MVFR VSBYS WITH SCATTERED SHOWERS. SEVERAL BANDS OF
SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE ACROSS THE REGION LATE
TONIGHT AND MONDAY FROM THE SOUTH WITH IFR TO OCCASIONALLY LIFR
CONDITIONS.
AFTER 18Z MONDAY: BANDS OF MODERATE TO HEAVY RAIN AND IFR
CONDITIONS ARE FORECAST MONDAY AFTERNOON THROUGH TUESDAY MORNING.
AT LEAST SCATTERED SHOWERS AND POSSIBLY THUNDERSTORMS WILL CONTINUE
TUESDAY AFTERNOON THROUGH LATE WEEK. LATE NIGHT LOW STRATUS (IFR TO
LIFR) WILL BE LIKELY.
RAH WATCHES/WARNINGS/ADVISORIES
FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR
NCZ007>011-021>028-038>043-073>078-083>086-088-089.
SYNOPSIS...BADGETT
NEAR TERM...BADGETT
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...BADGETT
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