834
FXUS62 KGSP 041041
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
641 AM EDT SUN OCT 4 2026
WHAT HAS CHANGED
PRECIP PROBABILITIES FOR THIS MORNING HAVE DECREASED.
AVIATION DISCUSSION HAS BEEN UPDATED FOR THE 12Z TAF ISSUANCE.
KEY MESSAGES
1. CLOUDY AND MUCH COOLER TODAY FOR MOST LOCATIONS, WITH AREAS
OF MOSTLY LIGHT RAIN/DRIZZLE POSSIBLE, MAINLY THIS AFTERNOON
AND EVENING.
2. NEAR-NORMAL TEMPERATURES AND DRY CONDITIONS ARE EXPECTED FOR
MUCH OF THE WORK WEEK, WITH LITTLE CHANCE FOR PRECIPITATION.
DISCUSSION
KEY MESSAGE 1: CLOUDY AND MUCH COOLER TODAY FOR MOST LOCATIONS,
WITH AREAS OF MOSTLY LIGHT RAIN/DRIZZLE POSSIBLE, MAINLY THIS
AFTERNOON AND EVENING.
THE LEADING EDGE OF A BACKDOOR COLD FRONT HAS SETTLED SOUTH
OF THE CWA THIS MORNING, WITH IN-SITU COLD AIR DAMMING/NOTABLY
COOLER/MORE STABLE AIR HAVING OVERTAKEN ALL BUT THE UPPER SAVANNAH
VALLEY. SHOWERS HAVE LARGELY VACATED THE SCENE AS A RESULT, TAKING
ANY EXCESSIVE RAINFALL THREAT ALONG WITH THEM.
COOL/STABLE AIR WILL ENCOMPASS VIRTUALLY THE ENTIRE CWA THROUGH
TONIGHT...LOCATIONS ACROSS THE SMOKIES AND VICINITY BEING A
SOMEWHAT NOTABLE EXCEPTION FOR THIS AFTERNOON. MAX TEMPS ARE
FORECAST TO BE ALMOST 10 DEGREES BELOW CLIMO IN MOST AREAS OUTSIDE
THE MOUNTAINS...MORE LIKE 0-5 DEGREES BELOW NORMAL ACROSS THE HIGHER
TERRAIN. CONDITIONS WILL REMAIN VERY MOIST, WITH PRECIPITABLE WATER
VALUES AOA 1.75" EXPECTED TO LINGER THROUGH THE DAY. A LOW AMPLITUDE
TROUGH AND ASSOCIATED ENTRANCE REGION OF AN UPPER JET WILL APPROACH
THE REGION THIS AFTERNOON, RESULTING IN SOME INCREASE IN UPWARD
VERTICAL MOTION. HOWEVER, LOW LEVEL FLOW/FORCING IS EXPECTED TO
REMAIN WEAK AS PRESSURES FALL WITHIN IN SITU COLD AIR DAMMING
REGION, SUCH THAT LITTLE TO NO ISENTROPIC LIFT IS EXPECTED. IF
ANYTHING, THE FLOW ABOVE THE SURFACE-BASED STABLE LAYER IS MORE
DOWNSLOPE/WNW THROUGH A GOOD CHUNK OF THE DAY. WHILE CHANCES
OF RAIN/DRIZZLE SHOULD RAMP UP TO THE SOLID CHANCE/LIKELY RANGE
THIS AFTERNOON, ESPECIALLY ACROSS THE SOUTHERN HALF OF THE AREA,
THE COMBINATION OF WEAK FORCING AND STABLE AIR SHOULD PRECLUDE
REDEVELOPMENT OF AN EXCESSIVE RAINFALL THREAT. THUNDERSTORMS ARE
GENERALLY NOT EXPECTED, EXCEPT FOR THE POTENTIAL FOR AN ISOLATED
STORM OR TWO ACROSS THE SMOKIES.
THE RAIN AND DRIZZLE WILL GRADUALLY DIMINISH TONIGHT AS THE UPPER
TROUGH AXIS SHIFTS EAST OF THE AREA AND SIGNIFICANT MID/UPPER LEVEL
DRYING OCCURS. LINGERING LOW LEVEL MOISTURE WITHIN RESIDUAL IN SITU
COOL POOL BENEATH THIS DRYING ALOFT WILL YIELD SOME POTENTIAL FOR
(AT LEAST) LOCALLY DENSE FOG LATE TONIGHT/EARLY MONDAY.
KEY MESSAGE 2: NEAR-NORMAL TEMPERATURES AND DRY CONDITIONS ARE
EXPECTED FOR MUCH OF THE WORK WEEK, WITH LITTLE CHANCE FOR
PRECIPITATION.
IN THE WAKE OF A DEPARTING UPPER TROUGH, CONTINENTAL HIGH PRESSURE
WILL STEADILY BUILD INTO THE REGION FROM THE NORTHWEST EARLY IN
THE WORK WEEK, WITH STEADY DEEP-LAYER DRYING EXPECTED TO BRING A
RETURN OF MOSTLY SUNNY CONDITIONS ON MONDAY. THIS ALLOW MAX TEMPS
TO WARM VERY CLOSE TO CLIMO DURING THE AFTERNOON. AS THE CENTER
OF SURFACE HIGH PRESSURE SETTLES OVER THE CENTRAL APPALACHIANS AND
MID-ATLANTIC MON NIGHT/TUE, TEMPS ARE FORECAST TO FALL TO AROUND 5
DEGREES BELOW CLIMO BEFORE REBOUNDING TO NEAR-NORMAL LEVELS AS THE
SURFACE HIGH MOVES OFF THE EAST COAST DURING MID-WEEK. TEMPS ARE
FORECAST TO REMAIN WITHIN A COUPLE OF DEGREES OF NORMAL THROUGH AT
LEAST FRIDAY. GENERAL WEAK SURFACE RIDGING IS EXPECTED TO REMAIN IN
PLACE OVER THE REGION THROUGH THE END OF THE WEEK, SO CONDITIONS
WILL REMAIN DRY AND HUMIDITY RELATIVELY LOW. GLOBAL MODELS ARE
IN GENERAL AGREEMENT THAT A SOUTHERN STREAM DISTURBANCE WILL LIFT
OUT ACROSS THE LOWER MISS VALLEY NEXT WEEKEND, BRINGING MORE CLOUD
COVER, SMALL POPS AND SLIGHTLY COOLER TEMPERATURES BY SATURDAY.
AVIATION /12Z SUNDAY THROUGH THURSDAY/
AT KCLT AND ELSEWHERE: A WEDGE OF STABLE AIR HAS INFILTRATED THE
TERMINAL FORECAST AREA THIS MORNING, AND THIS HAS BROUGHT AN END TO
MUCH OF THE SCATTERED CONVECTIVE ACTIVITY. MOST LOCATIONS ARE
REPORTING IFR CIGS, WITH SOME AREAS OF LIFR OR LOW MVFR ALSO NOTED.
AT LEAST TEMPO IFR/LIFR CIGS (AND MVFR VISBY) ARE EXPECTED TO
PERSIST THROUGH THE MORNING, WITH IMPROVEMENT TO MVFR EXPECTED
DURING THE EARLY AFTERNOON, WITH VFR BECOMING LIKELY BY LATE
AFTERNOON. THE APPROACH OF AN UPPER TROUGH MAY BRING A RETURN OF
AREAS OF MOSTLY -RA/POSSIBLE DZ...ESPECIALLY TO THE SOUTHERN HALF OF
THE AREA BY LATE AFTERNOON/EVENING. THIS WILL INCREASE THE POTENTIAL
FOR REDUCED VISBY ALONG WITH A RETURN OF RESTRICTED CIGS. HAVING
SAID THAT, CHANCES FOR PRECIP AT ANY TERMINAL ARE SUCH THAT ONLY
PROB30S ARE WARRANTED FOR NOW. CIGS WILL BEGIN TO RETURN TO IFR OR
LOWER BY LATE THIS EVENING, WITH INCREASED POTENTIAL FOR FOG AS
CONDITIONS DRY ALOFT, BUT THE LOW LEVELS REMAIN VERY MOIST.
OVERNIGHT VISBY IS MAINLY ADVERTISED IN THE 2-3SM RANGE FOR NOW, BUT
THE POTENTIAL IS THERE FOR LOWER VISBY. WINDS WILL REMAIN NE 5-10 KT
AT MOST SITES (LIGHT/VRBL AT KAVL), BECOMING LIGHT/VARIABLE AT ALL
LOCATIONS DURING THE AFTERNOON...CONTINUING THROUGH THE PERIOD.
OUTLOOK: IMPROVEMENT TO VFR IS EXPECTED IN MOST AREAS BY LATE
MONDAY MORNING. DRY VFR CONDITIONS ARE THEN EXPECTED TO PERSIST
THROUGH THE REST OF THE WEEK...EXCEPT FOR THE POTENTIAL FOR MORNING
VALLEY FOG/LOW STRATUS.
GSP WATCHES/WARNINGS/ADVISORIES
GA...NONE.
NC...NONE.
SC...NONE.
JDL
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