545
FXUS62 KGSP 091537
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1137 AM EDT MON MAR 9 2026
WHAT HAS CHANGED
DENSE FOG ADVISORY ALLOWED TO EXPIRE. REVISED KEY MESSAGE 1 TO
DISCUSS MCS POSSIBILITY TONIGHT.
KEY MESSAGES
1. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS POSSIBLE TONIGHT
AND TUESDAY. NEAR-RECORD WARMTH RETURNS TUESDAY.
2. A STRONG COLD FRONT ARRIVES WEDNESDAY NIGHT PRODUCING WIDESPREAD
SHOWERS, ISOLATED THUNDERSTORMS AND PERHAPS A LOW END SEVERE
WEATHER THREAT. MUCH COOLER AND DRIER WEATHER DEVELOPS BEHIND
THE FRONT FOR THU AND FRI.
DISCUSSION
KEY MESSAGE 1: SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS POSSIBLE
TONIGHT AND TUESDAY. NEAR-RECORD WARMTH RETURNS TUESDAY.
SPLIT-FLOW REGIME WILL REMAIN IN PLACE THRU TUESDAY; AHEAD OF
THE DEEP CUTOFF LOW NEAR BAJA CALIFORNIA, HEIGHTS WILL RISE AS
SOUTHWESTERLY FLOW OCCURS OUT OF THE WESTERN GULF, PROMOTING AN
INCREASINGLY WARM AND HUMID AIRMASS ACROSS THE LOWER MS VALLEY. THE
FRONT WHICH EFFECTIVELY REACHED OUR CWA AND STALLED LATE SUNDAY
WILL BE REACTIVATED ACROSS THE TN AND LOWER OH VALLEYS, LEAVING A
NW-SE ORIENTED GRADIENT OF MOISTURE/INSTABILITY FROM TN TO SC THIS
AFTERNOON AND TONIGHT. DRIVEN BY A WEAK SHORTWAVE AND 1000+ J/KG
MUCAPE UPSTREAM, CONDITIONS APPEAR FAVORABLE FOR AN MCS TO DEVELOP
IN THE ARKLAMISS REGION AND TRACK ESE ACROSS AL/GA TONIGHT. THOUGH
SUCH AN MCS WOULD STILL LOOK LIKELY TO BE STEERED JUST PAST OUR
AREA TO THE SW, CONSENSUS OF CAMS WOULD SUGGEST OUR WESTERN AREAS
MIGHT SEE LIGHT RAIN ON THE PERIPHERY OF THE SYSTEM, OR WEAK
CONVECTION COULD DEVELOP VIA THE ASSOCIATED MCV. EITHER CHANCE
WOULD APPEAR TO PEAK IN THE 10 PM TO 2 AM TIMEFRAME. REGARDLESS
OF THE MCS POSSIBILITY, THE MIDLEVEL CAPPING INVERSION WEAKENS
VIA THE SHORTWAVE WHILE MOIST SW FLOW CONTINUES AT 850MB. A FEW
HUNDRED JOULES OF MUCAPE THUS DEVELOP OVER THE CWA IN THE EARLY
MORNING HOURS TUESDAY. ACCORDINGLY CHANCE RANGE (30-50%) POPS
WILL EXPAND ACROSS THE AREA AT THAT TIME. PROG SOUNDINGS REMAIN
MARGINALLY FAVORABLE FOR CONVECTION THROUGH THE END OF THE DAY
TUESDAY, THOUGH WITH THE SHORTWAVE MOVING EAST OF THE CWA BY EARLY
AFTERNOON, THE BETTER CHANCE IS PROBABLY DURING THE MORNING. CAN'T
RULE OUT ISOLATED REDEVELOPMENT OVER THE MOUNTAIN RIDGES WHICH
THEN COULD PROPAGATE EASTWARD.
TEMPS THIS AFTERNOON WILL WARM SEVERAL DEGREES COMPARED TO SUNDAY
BUT ARE EXPECTED TO PEAK BELOW THE DAILY RECORDS. THE CURRENT
MAX TEMP FORECAST FOR TUE IS JUST A DEGREE SHY OF DAILY RECORDS
AT KCLT AND KGSP, AND WOULD BREAK THE RECORD AT KAVL BY A COUPLE
OF DEGREES. FOR WED, THE CURRENT FORECAST EXCEEDS DAILY RECORDS AT
KCLT AND KAVL, AND IS WITHIN A DEGREE OF THE RECORD AT KGSP. RECORD
WARM MIN TEMPS ARE ALSO LIKELY TO BE BROKEN TUE NIGHT.
KEY MESSAGE 2: A STRONG COLD FRONT ARRIVES WEDNESDAY NIGHT PRODUCING
WIDESPREAD SHOWERS, ISOLATED THUNDERSTORMS AND PERHAPS A LOW END
SEVERE WEATHER THREAT. MUCH COOLER AND DRIER WEATHER DEVELOPS
BEHIND THE FRONT FOR THU AND FRI.
A WEAKENING UPPER LOW IN THE SOUTHERN STREAM OF A SPLIT FLOW
REGIME WILL MOVE FROM TEXAS INTO THE DEEP SOUTH WED NIGHT, AS A
STRONG NORTHERN STREAM WAVE WILL BE DIGGING ACROSS THE GREAT LAKES
AND THE OHIO VALLEY...WITH PHASING OF THE TWO STREAMS EXPECTED
OVER THE EAST ON THURSDAY. ASSOCIATED STRONG FRONTAL ZONE IS
FORECAST TO MOVE INTO THE FORECAST AREA BETWEEN 06-12Z THURSDAY,
WARRANTING LIKELY-TO-CATEGORICAL POPS ACROSS THE ENTIRE AREA FROM
LATE WED NIGHT THROUGH THU MORNING. STRONG MOISTURE FLUX WILL
BE IN PLACE OFF THE GULF IN ADVANCE OF THE FRONT, WHICH COMBINED
WITH WARM/WELL-MIXED CONDITIONS COULD MAINTAIN A RIBBON OF WEAK
SURFACE-BASED INSTABILITY IMMEDIATELY AHEAD OF THE FRONT. THE
GLOBAL MODELS CONTINUE TO DEPICT A NARROW ZONE OF FOCUSED ASCENT
ALONG THE LEADING EDGE OF THE FRONT, WHICH COULD INTERACT WITH THE
WEAK INSTABILITY TO PRODUCE A LOW-TOPPED QUASI-LINEAR CONVECTIVE
SYSTEM. LIMITING FACTORS FOR AN ORGANIZED SEVERE STORM THREAT ARE
DUE TO THE DELAYED PHASING OF THE UPPER AIR PATTERN...WHICH MAY
NOT BE COMPLETED UNTIL THE UPPER TROUGH IS EAST OF THE FORECAST
AREA. THIS RESULTS IN FORCING NOT BEING AS DEEP AND STRONG AS ONE
WOULD USUALLY LIKE TO SEE FOR LOW CAPE ENVIRONMENTS. ADDITIONALLY,
LOW-LEVEL FLOW WILL BE VEERED AND LARGE UNIDIRECTIONAL...RESULTING
IN 0-1KM SHEAR VALUES OF 25-30 KTS...STRONG, BUT NOT THE 35+ KTS
THAT WE TYPICALLY NEED FOR ANYTHING MORE THAN A MARGINAL THREAT
IN WEAKLY UNSTABLE SITUATIONS. NEVERTHELESS, THE FORECAST PATTERN
AND INGREDIENTS WILL BE ADEQUATE FOR A LOW-END THREAT.
STRONG COLD ADVECTION WILL OVERSPREAD THE AREA DURING THE DAYLIGHT
HOURS THURSDAY, AND THE HIGH ELEVATIONS MAY SEE A TRANSITION
TO A BRIEF PERIOD OF SNOW OR A RAIN/SNOW MIX BEFORE THE PRECIP
ENDS...AND EVEN SOME LIGHT ACCUMS ARE POSSIBLE ABOVE 3500 FEET OR
SO. TEMPERATURES WILL RETURN TO LEVELS MORE SANE FOR LATE WINTER
THU-FRI, BUT THAT WILL BE SHORT-LIVED AS RETURN FLOW SETS UP AND
HEIGHT RISE OVER THE REGION...DOWNSTREAM OF MORE WESTERN CONUS
HEIGHT FALLS. AS A RESULT, TEMPS QUICKLY TO WELL-ABOVE NORMAL
LEVELS OVER THE WEEKEND...ALTHOUGH CONDITIONS WILL REMAIN DRY AS
MOISTURE WILL BE SLOWER TO INCREASE.
AVIATION /15Z MONDAY THROUGH FRIDAY/
AT KCLT AND ELSEWHERE: EXPECT DRY, VFR CONDITIONS THRU MOST OF
THE 12Z TAF PERIOD OUTSIDE OF PATCHY DENSE FOG AND LOW STRATUS
THIS MORNING. A HANDFUL OF TERMINALS ARE STILL REPORTING 1/4 SM
AND FG, WITH OTHERS REPORTING ANYWHERE FROM MVFR TO IFR. THESE
RESTRICTIONS ARE LIKELY TO LINGER THRU MOST OF THE MORNING AS
WINDS WILL REMAIN LIGHT TO CALM AND IT WILL TAKE SOME TIME FOR
DAYTIME HEATING TO HAVE A SUBSTANTIAL IMPACT. EXPECT ALL SITES
TO RETURN TO VFR BY 14 TO 15Z. OTHERWISE, WINDS WILL BE LIGHT
TO CALM WELL INTO THE MORNING. OUTSIDE THE MTNS, THEY WILL PICK
UP FROM THE WSW/SW DURING THE AFTERNOON WITH SPEEDS BETWEEN 5
AND 10 KTS. AT KAVL, WINDS WILL REMAIN LIGHT TODAY AND GENERALLY
FAVOR A NWLY DIRECTION THIS AFTERNOON. A PROB30 FOR -SHRA WAS
INCLUDED AT KCLT AND THE UPSTATE TERMINALS FOR TUESDAY MORNING/
AFTERNOON FOR THE SHOWER CHANCE.
OUTLOOK: THE SPRING-LIKE WEATHER PATTERN WILL LINGER FOR THE
NEXT FEW DAYS WITH PATCHY FOG/LOW STRATUS POSSIBLE EACH MORNING.
ISOLATED TSRA MAY RETURN TUES WITH BETTER TSRA CHANCES EXPECTED
WED NIGHT INTO EARLY THURS. GUSTY WINDS WILL DEVELOP WED INTO
THURS ACROSS THE AREA AS WELL. DRIER CONDITIONS RETURN LATE THURS
INTO FRI.
CLIMATE
RECORDS FOR 03-09
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 80 1974 22 1932 57 1964 8 1996
KCLT 83 2009 30 1960 62 1925 16 1996
1974 1921
1925
KGSP 85 2009 29 1960 60 2009 16 1996
1921
RECORDS FOR 03-10
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 76 1974 29 1932 58 1903 10 1996
1932
KCLT 82 1974 36 1924 59 1903 17 1932
KGSP 84 1974 39 1924 58 2009 17 1932
1997
RECORDS FOR 03-11
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 79 1967 29 1924 55 2016 14 1934
1925
KCLT 83 2015 37 1960 60 1986 22 1969
2009 1934
1990
KGSP 84 2009 34 1960 60 1986 17 1969
GSP WATCHES/WARNINGS/ADVISORIES
GA...NONE.
NC...NONE.
SC...NONE.
JCW/JDL
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