694
FXUS62 KGSP 231712
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1212 PM EST TUE DEC 23 2025
SYNOPSIS
A WARM UPPER RIDGE OVER THE LOWER MISSISSIPPI VALLEY WILL KEEP OUR
REGION WARM AND DRY FOR CHRISTMAS AND THE START OF THE WEEKEND. THE
WARM WEATHER WILL END DRAMATICALLY NEAR THE END OF THE WEEKEND AS
COLD AIR FROM CANADA DROPS THE TEMPERATURE ABOUT 30 DEGREES TO
START NEXT WEEK.
NEAR TERM /THROUGH WEDNESDAY/
AS OF 1210 PM EDT TUESDAY:
KEY MESSAGE #1: RELATIVELY QUIET WITH WARMING TEMPERATURES AND A
SLIGHT CHANCE OF RAIN FOR THE MOUNTAINS.
THE DOMINATING PATTERN OF HIGH PRESSURE ENSUES AS A RIDGE BUILDS IN
OVER THE CENTRAL CONUS AND A WEAK TROUGH OVER THE EASTERN U.S.
SURFACE HIGH PRESSURE REMAINS THE PRIMARY FEATURE OVER THE
SOUTHEAST, SUPPRESSING THE MAJORITY OF RAIN CHANCES. SOUTHWESTERLY
SURFACE WINDS SET UP AS THE HIGH MIGRATES EASTWARD TODAY WITH WINDS
BECOMING MORE WESTERLY, GIVING AN UPSLOPE COMPONENT ON THE WESTERN
SIDE OF THE APPALACHIANS. THE SW WINDS ENHANCE WAA ACROSS THE AREA,
INCREASING THE CHANCES FOR PRECIP ON OVER THE MOUNTAINS THROUGH
TONIGHT. AT BEST, A SLIGHT CHANCE (15-35%) FOR SPOTTY SPRINKLES, SO
NOTHING SIGNIFICANT OR ACCUMULATING. AS AN AREA OF LOW PRESSURE
PASSES OFF TO THE NE, THE WEAK TROUGHING EAST OF THE MOUNTAINS KICKS
UP WINDS, BRINGING A FEW HOURS OF GUSTY WINDS. EXPECT BRIEF WIND
GUSTS OF 25-30 MPH, ESPECIALLY IN THE NC PIEDMONT AND HIGHER
ELEVATIONS OF THE MOUNTAINS, THROUGH THIS EVENING. FOR WEDNESDAY,
DRY AND LIGHT WINDS. TEMPERATURES TODAY CREEP UP WELL ABOVE NORMAL
IN THE MID 60S, MOSTLY EAST OF THE MOUNTAINS. WEDNESDAY, TEMPS
INCREASE EVEN HIGHER TO NEAR RECORD WARMTH IN THE LOW 70S FOR
LOCATIONS EAST OF THE MOUNTAINS.
SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/
AS OF 1147 AM EST TUESDAY:
KEY MESSAGE: CHRISTMAS HEAT WAVE WILL BRING NEAR-RECORD WARMTH
CHRISTMAS DAY FOR MOST LOCATIONS AND THE DAY AFTER IN LOCATIONS
OUTSIDE OF A DEVELOPING WEDGE.
A DEEP UPPER RIDGE REMAINS PARKED OVER THE CENTRAL CONUS, WHILE
WEAK SURFACE RIDGING STAYS PUT OVER THE EASTERN SEABOARD WEDNESDAY
NIGHT INTO THURSDAY. ANOMALOUSLY HIGH THICKNESSES WILL BE IN
PLACE, LEADING TO VERY WARM TEMPERATURES ACROSS THE SOUTHEAST. A
WEAK SHORTWAVE IS SHOWN RIDING IN BETWEEN THE AFOREMENTIONED UPPER
RIDGE AND A DIGGING UPPER TROUGH OVER SOUTHEAST CANADA. THIS WILL BE
ENOUGH TO PROMOTE UPSLOPE NORTHWEST FLOW SHOWERS ALONG THE IMMEDIATE
TN BORDER WEDNESDAY NIGHT INTO THURSDAY, AS THE BETTER MOISTURE AND
FORCING FOR ASCENT REMAINS NORTH OF THE CWFA. DEEPER WARM ADVECTION
WILL BE IN STORE FOR CHRISTMAS AS WARM FRONTAL ACTIVATION OCCURS
AS THE ASSOCIATED SURFACE LOW WITH THE SHORTWAVE LIFTS SOUTH AND
EAST OF THE AREA, WHILE THE FLOW JUST ABOVE THE SURFACE SUPPORTS A
DOWNSLOPE COMPONENT. THIS WILL ALLOW FOR THE HEAT TO FULLY MAXIMIZE
CHRISTMAS DAY AS AFTERNOON HIGHS CLIMB 20-25 DEGREES ABOVE NORMAL,
BUT DAILY RECORDS ARE CONSIDERABLY WARM, SO BREAKING THE RECORD
WILL BE CHALLENGING. A STRONG SURFACE HIGH (~1035MB) WILL MOVE INTO
QUEBEC THURSDAY NIGHT AS THE SYNOPTIC PATTERN BEGINS TO TAKE ON A
HYBRID WEDGE CONFIGURATION. AT THE SURFACE, A WEAK BACKDOOR COLD
FRONT TRIES TO WORK INTO THE AREA FROM THE NORTHEAST. AS A RESULT,
A STARK CONTRAST IN AFTERNOON HIGHS ON FRIDAY WILL BE POSSIBLE,
WITH LIKELY A 15-20+ DEGREE DIFFERENCE BETWEEN LOCATIONS NORTH OR
SOUTH OF THE BOUNDARY. RIGHT NOW THE FORECAST FAVORS LOCATIONS
ALONG AND EAST OF THE I-26 CORRIDOR TO BE ON THE COOLER SIDE
(50S), WHILE WEST OF I-26 ENDS UP ON THE WARMER SIDE (70S),
SO THERE IS POTENTIAL FOR THE TEMPERATURE FORECAST TO BUST FOR
LOCATIONS IN THE VICINITY OF THE I-26 CORRIDOR ON FRIDAY. ANOTHER
WEAK SHORTWAVE WILL QUICKLY PUSH JUST NORTH OF THE AREA FRIDAY
AND PROMOTE ANOTHER ROUND OF UPSLOPE NORTHWEST FLOW PRECIP ALONG
THE IMMEDIATE TN BORDER. ALL PRECIPITATION THAT FALLS ACROSS THE
MOUNTAINS DURING THE SHORT-TERM WILL BE ALL LIQUID AS TEMPERATURE
PROFILES ARE TOO WARM FOR ANYTHING TO FREEZE.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/
AS OF 1209 PM EST TUESDAY:
KEY MESSAGES: WELL-ABOVE-NORMAL TEMPERATURES WILL CONTINUE THROUGH
THE WEEKEND. A PATTERN CHANGE INVOLVING THE ARRIVAL OF AN ARCTIC
FRONT IS LOOKING INCREASINGLY LIKELY EARLY NEXT WEEK.
CONTINUED DECEMBER HEAT WAVE WILL CARRY OVER INTO THE WEEKEND AS
THE AMPLIFIED UPPER RIDGE OVER THE CENTRAL CONUS GRADUALLY BEGINS
TO BREAKDOWN OVER THE WEEKEND, BUT THE AXIS MOVES OVER THE EASTERN
CONUS, KEEPING VERY WARM THICKNESSES IN PLACE. HOWEVER, CHANGES
WILL TAKE PLACE ON A SYNOPTIC BASIS AS A DIGGING UPPER LOW SETS
UP SHOP OVER THE GREAT LAKES AND NORTHERN MS VALLEY BY SUNDAY, AND
SENDS A STRONG ATTENDANT ARCTIC FRONT INTO THE EASTERN CONUS. RAPID
HEIGHT FALLS WILL ACCOMPANY THE COLD FRONT AS MODEL GUIDANCE ARE
IN GOOD AGREEMENT WITH THE FRONT MAKING A FROPA SUNDAY INTO SUNDAY
NIGHT. MAX TEMPERATURES SATURDAY AND SUNDAY WILL REMAIN 15-20
DEGREES ABOVE NORMAL, BUT A DRASTIC CHANGE BEHIND THE FRONT WILL
KNOCK AFTERNOON HIGHS BACK TO NEAR NORMAL AND EVEN A CATEGORY OR
SO BELOW NORMAL ACROSS THE MOUNTAINS BY MONDAY. DEEP CAA WILL KEEP
FULLY SETTLE IN BY TUESDAY, LEADING TO EVEN COLDER TEMPERATURES
FOR THE END OF THE FORECAST PERIOD. CAN'T RULE OUT SOME PRECIP
ACROSS THE CWFA, BUT THE MOISTURE RETURN AHEAD OF THE FRONT IS
MEAGER AND THE BETTER FORCING WILL RESIDE NORTH OF THE REGION,
SO RAIN CHANCES REMAIN IN THE SLIGHT CHANCE TO CHANCE CATEGORY.
AVIATION /18Z TUESDAY THROUGH SUNDAY/
AT KCLT AND ELSEWHERE: VFR CONDITIONS PREVAIL AT MOST SITES THROUGH
THE TAF PERIOD. HIGH PRESSURE REMAINS OVERHEAD AND KEEPS MOST
RESTRICTIONS OUT OF THE FORECAST. KAVL COULD SEE BRIEF BR BEFORE 12Z
SO WILL HAVE VSBY GOING DOWN TO MVFR AT 5SM FOR A FEW HOURS. --RA IS
POSSIBLE AT KAVL OVERNIGHT BUT CONFIDENCE IS TOO LOW TO PUT INTO THE
TAF AT THIS TIME. A MIX OF BKN/SCT CLOUDS TODAY AS WINDS HELP TO
CLEAR THEM OUT THROUGHOUT THE EVENING. WIND GUSTS OF 15-25KTS LIKELY
THROUGH THIS EVENING AT ALL SITES EXCEPT KAVL. WINDS SHOULD ALSO
MAINTAIN A SW/WSW DIRECTION OUTSIDE THE MOUNTAINS WHERE KAVL SHOULD
PREVAIL NW. KCLT SHOULD GO JUST NORTH OF WEST AT 280-290 OVERNIGHT
AS WELL. OTHER SITES ARE LIKELY TO BECOME LIGHT AND VRB TOWARD
DAYBREAK WEDNESDAY.
OUTLOOK: VFR CONDITIONS SHOULD PREVAIL THROUGH THE END OF THE WEEK.
PATCHY MTN VALLEY FOG AND LOW STRATUS EACH MORNING POSSIBLE.
CLIMATE
RECORDS FOR 12-24
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 72 1955 17 1906 59 2015 -5 1983
KCLT 73 2015 29 2022 63 2015 6 1983
1906
KGSP 71 1964 28 2022 61 2015 7 2022
RECORDS FOR 12-25
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 71 2021 14 1983 59 2015 -7 1983
KCLT 77 1955 22 1983 63 2015 4 1983
KGSP 78 1955 22 1983 61 2015 6 1983
RECORDS FOR 12-26
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 78 1971 17 1902 55 2015 0 1983
KCLT 77 2021 27 1983 58 2015 6 1983
1964
KGSP 76 2021 28 1983 62 1987 5 1985
2015 1980
RECORDS FOR 12-27
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 72 1971 19 1902 59 2015 3 1925
KCLT 72 2021 22 1892 65 2015 15 1970
2015 1948
1971 1925
KGSP 75 1971 29 1925 64 2015 12 1925
GSP WATCHES/WARNINGS/ADVISORIES
GA...NONE.
NC...NONE.
SC...NONE.
SYNOPSIS...DEO
NEAR TERM...CP
SHORT TERM...CAC
LONG TERM...CAC
AVIATION...CP
CLIMATE...
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