361
FXUS62 KRAH 170707
AFDRAH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
255 AM EDT SAT MAY 17 2025
SYNOPSIS
A COLD FRONT APPROACHING THE SOUTHERN APPALACHIANS THIS MORNING WILL
PUSH EAST AND SOUTHEAST ACROSS NORTH CAROLINA THIS AFTERNOON AND
ESPECIALLY TONIGHT AND THEN STALL ACROSS SOUTH CAROLINA AND GEORGIA
ON SUNDAY. COOLER AND DRIER HIGH PRESSURE WILL EXTEND INTO THE
REGION ON SUNDAY AND MONDAY. THE FRONT WILL LIFT NORTH ACROSS THE
CAROLINAS AS A WARM FRONT ON TUESDAY.
NEAR TERM /THROUGH TONIGHT/
AS OF 1000 PM FRIDAY...
EARLIER THIS AFTERNOON, A LINE OF SEVERE STORMS MOVED ACROSS
VIRGINIA AND EXTREME NORTHERN NORTH CAROLINA, BRINGING WIND DAMAGE
IN A SWATH ACROSS PERSON, GRANVILLE, VANCE, AND HALIFAX COUNTIES.
HOWEVER, MOST OF THE FORECAST AREA REMAINED DRY. THE SURFACE PATTERN
ACROSS NORTH CAROLINA IS CURRENTLY DIFFUSE, BUT ANOTHER ROUND OF
SEVERE THUNDERSTORMS HAVE BEEN MAKING ITS WAY ACROSS THE MIDWEST AND
OHIO VALLEY, AND IS APPEARING MORE LIKELY TO HOLD TOGETHER AS IT
MOVES INTO NORTH CAROLINA. CONSIDERING THE ARRIVAL TIME BEFORE
SUNRISE, THE SEVERITY OF THE THUNDERSTORMS THAT PERSIST WILL BE
DETERMINED BY THE MESOSCALE DYNAMICS ASSOCIATED WITH THE STORMS
THEMSELVES AS OPPOSED TO RESIDUAL DAYTIME HEATING. THE STORM
PREDICTION CENTER HAS MAINTAINED A SLIGHT (LEVEL 2 OF 5) RISK INTO
THE TRIAD THROUGH 8AM SATURDAY MORNING, AND THE LOCAL FORECAST
DOESN'T RULE OUT A THUNDERSTORM ANYWHERE ACROSS THE FORECAST AREA
BEFORE 8AM SATURDAY. OVERNIGHT LOWS WILL RANGE FROM THE MID 60S TO
THE MID 70S.
SHORT TERM /SATURDAY AND SATURDAY NIGHT/
AS OF 310 PM FRIDAY...
* THERE IS STILL A FAIR BIT OF UNCERTAINTY, HOWEVER A CONDITIONAL
THREAT FOR ISOLATED STRONG STORMS SAT AFT/EVE REMAINS.
ALOFT, THE SUB-TROPICAL RIDGE WILL REMAIN SUPPRESSED WELL SOUTH OF
THE AREA AS A CLOSED LOW TRACKS EWD ACROSS THE SRN/ERN GREAT LAKES
AND NORTHEAST US SAT/SAT NIGHT. A COUPLE OF SHORTWAVE DISTURBANCES
WITHIN THE ATTENDANT TROUGH WILL MOVE ACROSS THE REGION ON SAT
BEFORE THE TROUGH SHIFTS EWD OUT OF THE AREA SAT NIGHT. AT THE
SURFACE, THE PARENT LOW WILL OCCLUDE OVER THE GREAT LAKES ON SAT,
WHILE A SECONDARY LOW DEVELOPS OVER THE NORTHEAST US. THE ATTENDANT
COLD FRONT SHOULD PROGRESS EWD ACROSS THE AREA SAT AFT/EVE AS THE
SECONDARY LOW LIFTS NEWD ALONG THE NEW ENGLAND COAST.
UNCERTAINTY: THE BIGGEST UNCERTAINTY CONTINUES TO BE WHETHER THE
CONVECTION EXPECTED TO MOVE ACROSS THE MID-MS AND TN VALLEY REGIONS
TONIGHT, WILL HOLD TOGETHER AND MOVE INTO THE AREA EARLY SAT. AND IF
IT DOES MOVE INTO THE AREA, HOW LONG IT WILL HOLD TOGETHER. THEN,
HOW MUCH THE SHOWERS AND ASSOCIATED CLOUD COVER WILL STABILIZE THE
ATMOSPHERE AND/OR LIMIT DESTABILIZATION DURING THE AFT/EVE, THUS
IMPACTING WHETHER SHOWERS WILL RE-DEVELOP ALONG THE FRONT AND MOVE
ACROSS THE AREA SAT EVE/NIGHT. LATEST HI-RES GUIDANCE CONSENSUS HAS
THE SHOWERS/ISO STORMS HOLDING TOGETHER AND MOVING INTO THE WESTERN
PIEDMONT AROUND DAYBREAK SAT, THEN WEAKENING AND/OR DISSIPATING
SOMEWHERE OVER CENTRAL NC SAT MORN.
CONVECTION: FORECAST SOUNDINGS OFF THE NAM SHOW DESTABILIZATION
ACROSS MUCH OF THE AREA (ALBEIT BRIEFLY IN THE NW), WITH HIGHEST
CAPE VALUES ACROSS THE SANDHILLS AND COASTAL PLAIN DURING THE
AFT/EVE. MAX MUCAPE AROUND 2000 J/KG WITH EFFECTIVE SHEAR AROUND 40
KTS AT KFAY AND KRWI (AND BRIEFLY AT KRDU). ADDITIONALLY, WITH 25-35
KTS AT THE TOP OF THE MIXED LAYER, WIND GUSTS IN THAT RANGE WILL BE
POSSIBLE UNTIL THE NOCTURNAL INVERSION SETS UP SAT EVE. ADDITIONAL
SHOWERS/STORMS COULD DEVELOP DURING THE AFT/EVE ALONG/AHEAD OF THE
FRONT IF ENOUGH DESTABILIZATION IS REALIZED, AND COULD RESULT IN
STRONG WIND GUSTS AND POSSIBLY SOME HAIL. HOWEVER, THERE IS STILL
SOMEWHAT LOW CONFIDENCE IN TIMING, LOCATION, AND COVERAGE OF THAT
THREAT, IF IT MATERIALIZES.
TEMPERATURES: ALSO DEPENDENT ON WHAT HAPPENS WITH THE EARLY
CONVECTION SAT MORN, BUT FOR NOW EXPECT HIGHS RANGING FROM MID 80S
NW TO LOW 90S SE. BASED ON CURRENT TIMING OF THE FRONT, EXPECT LOWS
TO RANGE FROM LOW 60S NW TO UPPER 60S SE.
LONG TERM /SUNDAY THROUGH FRIDAY/
AS OF 205 PM FRIDAY...
* LARGELY UNSETTLED WEATHER IS EXPECTED FOR THE BEGINNING OF THE
EXTENDED PERIOD, UNTIL A COLD FRONT MOVES THROUGH THE REGION
WEDNESDAY OR THURSDAY.
* TEMPERATURES WILL REMAIN ABOVE AVERAGE UNTIL WEDNESDAY, WITH BELOW
AVERAGE TEMPERATURES EXPECTED THURSDAY AND FRIDAY.
SUNDAY AND MONDAY, A FRONT IS EXPECTED TO BE QUASI-STATIONARY TO OUR
SOUTH. THESE DAYS ARE EXPECTED TO BE MOSTLY DRY, HOWEVER AFTERNOON
SHOWERS MAY DEVELOP IN THE SOUTH DEPENDING ON HOW FAR NORTH THE
FRONT STALLS. OTHERWISE, TEMPERATURES SHOULD BE AROUND 5 DEGREES
ABOVE AVERAGE, WITH MAXIMUM TEMPERATURES ON BOTH DAYS IN THE LOW 80S
IN THE NORTH, TO THE UPPER 80S, MAYBE REACHING LOW 90S IN THE SOUTH.
SUNDAY AND MONDAY NIGHT SHOULD ALSO HAVE LOWS IN THE 60S.
RAIN CHANCES INCREASE AGAIN TUESDAY AFTERNOON AS LOW PRESSURE
ASSOCIATED WITH THE PREVIOUSLY STALLED FRONT PROGRESSES NORTH OF THE
REGION THROUGH THE MID ATLANTIC. THERE IS LARGE MODEL SPREAD ON THE
STRENGTH, TIMING, AND LOCATION OF THIS SYSTEM, HOWEVER MODELS ARE
GENERALLY SHOWING A WARM FRONT MOVING NORTH THROUGH THE REGION ON
TUESDAY, INCREASING RAIN CHANCES, AND A COLD FRONT MOVING THROUGH
THE REGION WEDNESDAY AFTERNOON OR THURSDAY MORNING. THUS, THERE ARE
RAIN CHANCES TUESDAY AND WEDNESDAY, WHICH COULD POTENTIALLY LINGER
INTO THURSDAY. THE BEST CHANCE FOR WIDESPREAD RAIN CURRENTLY LOOKS
TO BE WEDNESDAY AFTERNOON.
TEMPERATURES SHOULD FALL BEHIND THE FRONT, LEAVING MAXIMUM
TEMPERATURES IN THE 70S ON THURSDAY. HIGH PRESSURE SHOULD BUILD IN
BEHIND THE COLD FROPA, LEAVING FRIDAY DRY AND KEEPING MAXIMUM
TEMPERATURES IN THE 70S.
AVIATION /06Z SATURDAY THROUGH WEDNESDAY/
AS OF 255 AM SATURDAY...
VFR CONDITIONS ARE NOTED ACROSS CENTRAL NC EARLY THIS MORNING UNDER
A VEIL OF HIGH CIRRUS CLOUDS WITH CEILINGS AROUND 20KFT. A BAND OF
THUNDERSTORMS THAT MOVED ACROSS THE OH AND TN VALLEYS ON FRIDAY
AFTERNOON CONTINUES TO MARCH EAST AND WAS MOVING ACROSS THE WESTERN
SLOPES OF THE SOUTHERN APPALACHIANS AT AROUND 06Z. THIS BAND OF
CONVECTION IS FORECAST TO MOVE QUICKLY EAST AND LIKELY WEAKEN AS IT
MOVES EAST OF THE MOUNTAINS INTO THE NC FOOTHILLS DURING THE PREDAWN
HOURS. THE CONVECTION SHOULD ARRIVE IN THE TRIAD TERMINALS BETWEEN
09-12Z WITH A THREAT OF STRONG GUSTY WINDS OF 35KTS IN A FEW OF THE
THUNDERSTORMS ALONG WITH VSBY AND CIG RESTRICTIONS. THE CONVECTION
SHOULD SHIFT EAST AND SOUTHEAST AND WEAKEN A BIT, REACHING THE
TRIANGLE AREA BETWEEN 10 AND 13Z. THE CONVECTION WILL LIKELY WEAKEN
TO JUST SHOWERS AS THEY MOVE INTO THE FAYETTEVILLE AND ROCKY MOUNT
AREAS AS JUST SHOWERS BETWEEN 11 AND 15Z. AFTER THE INITIAL BAND OF
CONVECTION SHIFTS SOUTHEAST OF THE AREA, GENERALLY VFR CONDITIONS
ARE EXPECTED WITH WEST WINDS WILL INCREASE DURING THE DAY WITH WINDS
OF 15KTS AND GUSTS OF 25 TO 35KTS AT TIMES LATE THIS MORNING AND
THIS AFTERNOON. FAIR WEATHER IS EXPECTED TONIGHT WITH WINDS BECOMING
LIGHT WESTERLY AT 5 TO 10 KTS.
PERIODS OF LLWS ARE EXPECTED EARLY THIS MORNING AHEAD OF THE
CONVECTION WITH A 40 TO 45KT SOUTHWESTERLY LOW LEVEL JET. THE LLWS
THREAT WILL DISSIPATE AS THE CONVECTION MOVES ACROSS THE AREA THIS
MORNING. HOWEVER, ANOTHER PERIOD OF LLWS IS POSSIBLE THIS EVENING AS
SURFACE WINDS RELAX BUT A STRONG WESTERLY LOW LEVEL JET OF AROUND
50KTS MAY RESULT IN AREAS OF LLWS MAINLY FROM RALEIGH EAST UP UNTIL
AROUND MIDNIGHT.
LOOKING BEYOND THE 24 HOUR TAF PERIOD: MAINLY FAIR WEATHER IS
EXPECTED FOR SUNDAY AND INTO MONDAY WITH A THREAT OF MAINLY
AFTERNOON AND EVENING STORMS ON TUESDAY AND WEDNESDAY. AREAS OF LATE
NIGHT AND EARLY MORNING LOW STRATUS AND FOG IS POSSIBLE ON TUESDAY
AND ESPECIALLY WEDNESDAY. -BLAES
RAH WATCHES/WARNINGS/ADVISORIES
NONE.
SYNOPSIS...BLAES
NEAR TERM...GREEN
SHORT TERM...KC
LONG TERM...HELOCK
AVIATION...BLAES
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