548  
FXUS62 KGSP 152216  
AFDGSP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC  
516 PM EST SAT FEB 15 2025  
   
SYNOPSIS
 
 
A COLD FRONT CROSSES THE AREA SUNDAY WITH SHOWERS AND PERHAPS  
ISOLATED THUNDERSTORMS. BRISK WINDS DEVELOP SUNDAY NIGHT INTO MONDAY  
WITH AN INCOMING DRY HIGH PRESSURE SYSTEM. ANOTHER LOW PRESSURE  
SYSTEM CROSSES THE AREA AROUND WEDNESDAY, BRINGING A CHANCE FOR  
WINTRY WEATHER. COLD AND DRY HIGH PRESSURE RETURN LATE NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH SUNDAY/
 
 
KEY MESSAGES:  
 
1) PERIODS OF LIGHT RAIN AND DRIZZLE EXPECTED ACROSS MOST OF THE  
AREA THIS EVENING WITH COOL TEMPERATURES.  
 
2) WIND ADVISORY FOR THE ENTIRE CWA IN EFFECT EARLY SUNDAY THROUGH  
THE AFTERNOON FOR GUSTY WINDS OF 30-40 MPH EAST OF THE MOUNTAINS  
AND 45+ MPH IN THE MOUNTAINS THROUGH EARLY MONDAY MORNING.  
 
3) A COLD FRONT BRINGS LINE OF SHOWERS AND THUNDERSTORMS INTO THE  
NC MOUNTAINS BEFORE DAYBREAK SUNDAY, WITH A NON-ZERO THREAT OF  
SEVERE STORMS.  
 
4) NW FLOW SNOW POSSIBLE ALONG THE TN/NC BORDER BEHIND THE FRONT.  
 
AS OF 512 PM EST SATURDAY: A QUICK UPDATE FOR TEMP/DEWPT/RADAR  
TRENDS AND TO UPDATE THE HEADLINES IN THE TEXT PRODUCTS.  
 
OTHERWISE...A MESSY FORECAST AHEAD AS THE NEAR TERM CONTINUES  
IN THE MIDDLE OF A SOGGY AND RAINY DAY. PRESENTLY, SURFACE HIGH  
PRESSURE IS SOCKING IN CAD THIS AFTERNOON. OFF TO THE WEST, A  
STRENGTHENING SURFACE LOW LIFTS TOWARD THE NW AND EJECTS A STRONG  
COLD FRONT ACROSS THE CWA. WITH THIS VERY BUSY NEAR TERM, LET'S  
EXAMINE ONE ELEMENT AT A TIME. PRE-FRONTAL SHOWERS CONTINUE TO  
STREAM ACROSS PORTIONS OF THE AREA, DEVELOPING LOW-LEVEL CLOUDS,  
LOCKING IN THIS DREARY DAY. BY THIS EVENING AND OVERNIGHT HOURS,  
THE AREA OF LOW PRESSURE SHOVES THE HIGH PRESSURE OFFSHORE,  
HELPING TO ERODE THE CAD THAT'S BEEN PLAGUING THE AREA. WHAT'S  
LEFT BEHIND IS VERY LOW STRATUS AND THE POTENTIAL FOR PATCHY TO  
EVEN AREAS OF DENSE FOG AHEAD OF THE FRONT. SURFACE WINDS SHOULD  
REMAIN LIGHT TO EVEN CALM EAST OF THE MOUNTAINS THROUGH AT LEAST  
MIDNIGHT, CONTRIBUTING TO ANY FOG DEVELOPMENT. THE NEXT ELEMENT  
TO AFFECT THE AREA COMES IN EARLY SUNDAY MORNING. A STRONG COLD  
FRONT PUSHES THROUGH AND BRINGS WIDESPREAD RAIN, GUSTY WINDS AND  
THE POTENTIAL FOR THUNDERSTORMS. THE GOOD NEWS IS THIS FRONT AND  
LINE OF STORMS ARE EXPECTED TO QUICKLY SWEEP THROUGH THE AREA AND  
BY GONE BY NOON, IF NOT EARLIER. THOUGH THIS SAME LINE IS LIKELY  
TO PRODUCE SEVERE WEATHER FOR THE FOLKS FURTHER SOUTH, GUIDANCE IS  
LIMITING THE AVAILABLE INGREDIENTS FOR THIS AREA THAT COULD SUPPORT  
STRONG THUNDERSTORMS. ALOFT, PLENTY OF SHEAR, 50-70KTS, AND STRONG  
FORCING BY THE FRONT ITSELF. AS FOR INSTABILITY, MODELED SOUNDINGS  
ARE NOT IMPRESSED AND PLACE ZERO SBCAPE AND VERY LITTLE (0-50 J/KG)  
OF MUCAPE. WITHOUT THE INSTABILITY, ESPECIALLY AT THE SURFACE, THE  
CHANCE FOR SEVERE WEATHER BECOMES LOW. GIVEN THE SYNOPTIC SETUP  
AND OTHER INGREDIENTS IN PLAY, CANNOT RULE OUT DAMAGING WINDS OR  
HEAVY RAINFALL WITH THIS FRONTAL PASSAGE. ALL IN ALL, CONFIDENCE  
IS LOW TO SEVERE BUT REMAINS NONZERO. THE NEXT ELEMENT OF CONCERN  
IS GOING TO BE THE WINDS, ESPECIALLY ACROSS THE MOUNTAINS. GIVEN  
THE STRONG SHEAR ALOFT AHEAD OF THE FRONT, WINDS START TO PICK UP  
AFTER MIDNIGHT FOR THE NC MOUNTAINS AND BY DAYBREAK ELSEWHERE. WIND  
GUSTS OF 30-40 MPH IS LIKELY IN THE UPSTATE AND NC PIEDMONT, WITH  
HIGHER GUSTS IN THE MOUNTAINS. FOR THIS A WIND ADVISORY WILL BE  
IN EFFECT FOR THE ENTIRE CWA DURING PORTIONS OF THIS NEAR TERM AND  
INTO THE BEGINNING OF THE NEXT. WINDS START TO DIMINISH BY SUNDAY  
AFTERNOON. THE LAST ELEMENT OF DISCUSSION IS THERE COULD BE SOME  
MOISTURE WRAPPING AROUND THE LOW WITH THIS CAA AT THE HIGHER PEAKS,  
INDICATING A BIT OF NW FLOW SNOW AT THE TYPICAL TN/NC BORDER. SNOW  
AMOUNTS ARE LOW, 1-2" AT MOST. TEMPERATURES TODAY REMAIN BELOW  
NORMAL BUT QUICKLY WARM UP TOMORROW AS THE CAD IS ERODED AND THE  
AIR IS DRIER.  
 

 
   
SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/
 
 
AS OF NOON SATURDAY: NORTHWEST-FLOW SNOWFALL LOOKS TO CONTINUE INTO  
SUNDAY NIGHT WITH SHALLOW MOIST LAYER BANKED AGAINST THE  
APPALACHIANS. THE PBL ALONG THE NC/TN BORDER WILL COOL SUCH THAT A  
PORTION OF THIS MOISTURE WILL OVERLAP WITH TEMPERATURES IDEAL FOR  
DENDRITIC SNOW GROWTH OVERNIGHT THROUGH DAYBREAK MONDAY, WITH  
MOISTURE DIMINISHING OVER THE REMAINDER OF THE MORNING. SURFACE TEMPS  
WILL BOTTOM OUT IN THE LOWER TO MID TEENS ACROSS THE HIGHER  
ELEVATIONS MONDAY MORNING. VERY STRONG WINDS, AVERAGING ABOUT 40-45  
MPH IN THE PBL, WILL PERSIST THROUGH SUNDAY NIGHT AS WELL, AND A FEW  
GUSTS OF 55-65 MPH ARE POSSIBLE ON RIDGETOPS. WIND CHILLS WILL EASILY  
DROP TO AROUND ZERO OR A LITTLE BELOW WHERE THESE WINDS AND TEMPS  
OVERLAP, AND A FEW SPOTS MAY MEET THE COLD WX ADVISORY CRITERION  
(WIND CHILL -5 TO -14). MAX TEMPS MONDAY WILL BE BUOYED BY  
DOWNSLOPING EAST OF THE MOUNTAINS BUT STILL TOP OUT 5-8 DEGREES BELOW  
CLIMO UNDER ONGOING CAA. THE MORNING COULD PROBABLY BE DESCRIBED AS  
BREEZY ACROSS THE PIEDMONT BUT WELL BELOW WIND ADVISORY CRITERIA.  
 
SNOW WILL TAPER OFF DURING THE MORNING AS THE PBL TRENDS DRIER. DRY  
HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE CWA THROUGH TUESDAY AND  
POPS REMAINING NEAR ZERO FOR THE REST OF THE SHORT TERM PERIOD. TEMPS  
REBOUND TO JUST SLIGHTLY BELOW CLIMO MONDAY NIGHT AND TUE.  
 

 
   
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/
 
 
AS OF 100 PM SAT: UPPER LOW WILL CUT OFF OVER THE NORTHERN PLAINS BY  
WEDNESDAY MORNING, WITH A LOW AMPLITUDE SHORTWAVE TROUGH ACCELERATING  
AHEAD OF IT AND CROSSING THE MID-SOUTH WEDNESDAY. THIS LATTER FEATURE  
WILL ADVANCE TO THE NC/VA COAST BY EARLY THURSDAY. GLOBAL MODELS  
CONTINUE TO DEPICT MILLER A-TYPE SFC LOW NEAR THE CENTRAL GULF COAST  
AT 12Z WED, WHICH TRACKS GENERALLY TO OUR SOUTH THROUGH WEDNESDAY  
EVENING. MODELS APPEAR TO BE IN DECENT AGREEMENT ON THIS GENERAL  
EVOLUTION. 12Z CYCLE ECMWF, ALONG WITH BOTH EC AND GFS ENSEMBLE  
MEANS, HAVE TRENDED TOWARD A SLIGHTLY FASTER DEEPENING OF THE LOW  
ALTHOUGH THE TRACK HAS NOT CHANGED MUCH. THE CLOSED UPPER LOW WILL BE  
ASSOCIATED WITH A 1050+ MB HIGH OVER EASTERN MONTANA AND VICINITY;  
RIDGING WILL EXTEND TO THE MID-ATLANTIC COAST AND CONFLUENCE  
DOWNSTREAM OF THE TROUGH MAY LEAD TO A SMALL CLOSED HIGH TO OUR NORTH  
SUPPORTING CAD ON WED AND A VERY DRY SFC LAYER.  
 
THE MILLER-A IS LIKELY TO BRING PRECIP SHIELD OVER THE AREA ON WED.  
THE CRITICAL DIFFERENCE AMONG MODELS APPEARS TO BE HOW WELL THE  
PRECIP OVERCOMES WHAT MAY BE EXCEPTIONALLY DRY AIR AT ONSET, AND HOW  
TEMPS RESPOND. THERE ARE SLIGHT DIFFERENCES IN TIMING THAT LIMIT  
CONFIDENCE, BUT THESE TEMPERATURE DISCREPANCIES ARE THE MAIN FACTOR  
IN A LOW-CONFIDENCE FORECAST, AT LEAST IN THE SENSE OF PRECIP TYPE  
TRENDS OR OVERALL IMPACT. THE PRESENCE OF ICE NUCLEI DOES NOT APPEAR  
TO BE AN ISSUE AT THE ONSET OF PRECIP, WHICH MOST LIKELY WILL NOT  
OCCUR UNTIL AFTER DAYBREAK WEDNESDAY; POPS ARE MAINLY IN THE 10-30%  
RANGE TUESDAY NIGHT, REFLECTING POSSIBILITY OF EARLIER ONSET. THE  
MOST PLAUSIBLE MIDDLE-GROUND SCENARIO, TAKING THIS INTO ACCOUNT, IS  
FOR RAIN OR SNOW EARLY IN THE EVENT, EVEN AFTER POPS RAMP UP INTO THE  
LIKELY TO CATEGORICAL RANGE (FROM SW TO NE) DURING THE DAY WED. WITH  
LOW CONFIDENCE ON TEMPERATURE, HAVE TRIED TO MINIMIZE THE EXPANSE OF  
SUBFREEZING TEMPS EARLY IN THE EVENT, LEAVING MENTION AS A RAIN/SNOW  
MIX IN MUCH OF THE CWA WHERE TEMPS HOVER JUST ABOVE FREEZING. A WARM  
NOSE MAY ALSO COME INTO PLAY AND SOME SLEET COULD MIX IN AT THIS  
TIME. AS THE LOW PASSES THE AREA WED EVENING AND DRYING OCCURS ALOFT,  
P-TYPE CHANGES TO FZRA IN PORTIONS OF THE PIEDMONT WHERE TEMPS FALL  
BELOW FREEZING; WRAPAROUND MOISTURE KEEPS SNOW GOING OVER THE  
MOUNTAINS. MOST PRECIP WILL END WEDNESDAY NIGHT, BUT NW FLOW SNOW  
COULD CONTINUE THU ALONG THE TN BORDER.  
 
THE REMAINDER OF THE FORECAST WILL BE DRY AND COLD AS THE ARCTIC AIR  
REMAINS OVER THE SOUTHERN US. MIN/MAX TEMPS WILL BE 15-20 BELOW  
NORMAL THU-FRI.  
 

 
   
AVIATION /22Z SATURDAY THROUGH THURSDAY/
 
 
AT KCLT AND ELSEWHERE: RESTRICTIONS REMAIN IN PLACE FOR ALL  
TERMINALS THROUGH THE MAJORITY OF THE PERIOD AS A COLD FRONT MOVES  
TOWARD THE AREA. WIDESPREAD IFR/LIFR CIGS/VSBY EXPECTED TO LINGER  
THROUGH DAYBREAK AT ALL SITES. THIS AFTERNOON AND EVENING, -RA ALSO  
LINGERS AT ALL SITES WITH SOME PATCHY AREAS OF -SHRA BEFORE THE  
FRONT MOVES IN AFTER 10Z SUNDAY. AHEAD OF THE FRONT, LLWS AT ALL  
SITES FOR A PERIOD OVERNIGHT AS WINDS 2000FT AGL ARE LIKELY TO REACH  
35-40KT. THIS SHOULD DIMINISH BEFORE THE FRONT ARRIVES. THE FRONT  
MOVES INTO KAVL AROUND 10Z AND ELSEWHERE AFTER 11Z, HENCE PROB30S  
FOR TSRA AT ALL SITES. CONFIDENCE IS HIGH THAT THIS SYSTEM BRINGS  
GUSTY WINDS OF 25-30KTS AT THE SURFACE. EXPECT WINDS TO REMAIN NE  
THROUGH THIS AFTERNOON, BECOMING S AS THE HIGH PRESSURE OFF TO THE  
NORTH MOVES AWAY. VFR CONDITIONS ARE EXPECTED TO RETURN AT ALL  
TERMINALS ONCE THE FRONT MOVES OUT OF THE AREA.  
 
OUTLOOK: VFR CONDITIONS RETURN LATE SUNDAY INTO EARLY NEXT WEEK.  
ANOTHER SYSTEM MAY BRING PRECIP AND RESTRICTIONS TO THE REGION BY  
WEDNESDAY.  
 

 
   
GSP WATCHES/WARNINGS/ADVISORIES
 
 
GA...WIND ADVISORY FROM 6 AM TO 6 PM EST SUNDAY FOR GAZ010-017-018-  
026-028-029.  
NC...WIND ADVISORY FROM 6 AM TO 6 PM EST SUNDAY FOR NCZ035>037-056-  
057-068>072-082-502-504-506-508-510.  
WIND ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST MONDAY FOR  
NCZ033-048>053-058-059-062>065-501-503-505-507-509.  
SC...WIND ADVISORY FROM 6 AM TO 6 PM EST SUNDAY FOR SCZ008>014-019-  
101>109.  
 

 
 

 
 
SYNOPSIS...WIMBERLEY  
NEAR TERM...CP/PM  
SHORT TERM...WIMBERLEY  
LONG TERM...WIMBERLEY  
AVIATION...CP  
 
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