823  
FXUS62 KCHS 160553  
AFDCHS  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHARLESTON SC  
1253 AM EST SUN FEB 16 2025  
   
SYNOPSIS
 
 
A STRONG COLD FRONT WILL IMPACT THE AREA SUNDAY, FOLLOWED BY  
HIGH PRESSURE FOR MONDAY AND TUESDAY. A LOW PRESSURE SYSTEM  
WILL MOVE ACROSS THE REGION DURING THE MIDDLE OF NEXT WEEK.  
HIGH PRESSURE WILL THEN RETURN LATE NEXT WEEK.  
 

 
   
NEAR TERM /UNTIL 6 AM THIS MORNING/
 
 
IN THE WAKE OF THE WARM FRONT, TEMPERATURES ACROSS THE FORECAST  
AREA HAVE WARMED INTO THE MID TO UPPER 60S. TEMPERATURES SHOULD  
REMAIN GENERALLY STEADY THROUGH THE REST OF THE NIGHT, COOLING  
BY A DEGREE OR TWO. COASTAL WEB CAMERAS HAVE TRENDED WITH LESS  
FOG, THIS TREND IS EXPECTED TO CONTINUE FOR THE REST OF TONIGHT.  
REGIONAL RADAR COMPOSITE INDICATES THAT A SOLID LINE OF SHOWERS  
WITH EMBEDDED THUNDERSTORMS WAS PUSH ACROSS THE MS/AL LINE AT  
1250 AM. THIS LINE WILL REMAIN WEST AND UPSTREAM OF THE FORECAST  
AREA BY DAYBREAK. HOWEVER, IT IS POSSIBLE THAT A PORTION OF SE  
GA AND SC COULD BE PLACED IN WITHIN A SEVERE THUNDERSTORM WATCH.  
 

 
   
SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/
 
 
SUNDAY: A POTENT UPPER LEVEL WAVE WILL ADVECT EAST SUNDAY  
MORNING WITH A SEASONABLY STRONG 250 MB JET STREAK APPROACHING  
THE AREA (140 - 150 KT). AT 500 MB, THE MID-LEVEL WAVE WILL BE  
OVER THE SOUTHERN OHIO RIVER VALLEY AROUND SUNRISE WITH 200 M  
HEIGHT FALLS APPROACHING. THE WAVE WILL THEN BEGIN TO TAKE ON A  
NEGATIVE TILT AS IT EJECTS NORTHEAST WITH THE CORE OF THE DCVA  
AND HEIGHT FALLS MOVING ALONG THE SPINE OF THE APPALACHIANS.  
ACROSS SC/ GA 80/100 M HEIGHT FALLS WILL STILL MOVE EAST OVER  
THE REGION. AT 850/ 925 MB, THE PGF IS FORECAST TO TIGHTEN  
THROUGH THE MORNING PERIOD WITH THE LLJ PEAKING AT 50 TO 60 KT  
OVERHEAD. AT THE SURFACE, A COLD FRONT AND ASSOCIATED LINE OF  
SHOWERS (WITH A RUMBLE OF THUNDER POSSIBLE) WILL BE APPROACHING  
THE WESTERN ZONES BETWEEN 6 AND 8 AM.  
 
TIMING-- SEVERE WEATHER LINE:  
* I-95 BETWEEN 9 - 11 AM  
* THE GA/ SC COAST BETWEEN 11 AM - 1 PM.  
 
SUNDAY SEVERE THREAT: THE MAIN CONCERN FOR SUNDAY WILL BE THE  
CHANCE FOR SEVERE WEATHER/ STRONG TO LOCALLY DAMAGING WIND  
GUSTS. CLOUD BEARING SHEAR VALUES ARE AROUND 50 KT ALONG THE  
LINE, HOWEVER INSTABILITY IS EXTREMELY LIMITED (ONLY AROUND 100  
J/KG OF MU CAPE). AS MENTIONED ABOVE THOUGH, 50 - 60 KT OF WIND  
IS FORECAST TO BE IN THE 925/850 MB LAYER AND WITH ANY DOWNWARD  
MOMENTUM TRANSFER, LOCALLY DAMAGING WIND GUSTS WILL BE  
POSSIBLE. THE GREATEST INSTABILITY, IS TOWARDS SOUTHERN GA AND  
THEREFORE SPC HAS INTRODUCED A SLIGHT RISK FOR SEVERE WEATHER  
ACROSS GA, AND CONTINUED A MARGINAL RISK FOR SC.  
 
WIND THREAT: A WIND ADVISORY IS ALSO IN EFFECT FOR ALL ZONES  
FROM 5 AM THROUGH 6 PM SUNDAY. AHEAD OF THE COLD FRONT, WINDS  
WILL START TO APPROACH WIND ADVISORY CRITERIA AND REMAIN GUSTY  
AFTER THE LINE PASSES AND A COLD FRONT SWEEPS ACROSS THE REGION.  
LATEST FORECAST SOUNDINGS SHOW WIND GUSTS BEHIND THE COLD FRONT  
AROUND 30 KT (VIA MOMENTUM TRANSFER TECHNIQUES), OR JUST SHY OF  
WIND ADVISORY CRITERIA. GIVEN THE STRONG CAA THOUGH, HAVE OPTED  
TO KEEP THE WIND ADVISORY UNTIL 6 PM SUNDAY.  
 
MONDAY AND TUESDAY: SURFACE HIGH PRESSURE WILL BUILD OVER THE  
REGION FOR MONDAY AND TUESDAY. QUIET AND DRY WEATHER IS  
EXPECTED. THERE WILL BE PLENTY OF SUNSHINE, ALTHOUGH CLOUD COVER  
WILL BE ON THE INCREASE DURING THE LATTER HALF OF THE DAY  
TUESDAY. SEASONALLY COOL TEMPERATURES MAINLY IN THE MID 50S ON  
MONDAY WILL MODERATE CLOSER TO NORMAL FOR TUESDAY. LOWS MONDAY  
NIGHT WILL RANGE FROM THE LOW 30S INLAND TO UPPER 30S/AROUND 40  
CLOSER TO THE COAST.  
 

 
   
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/
 
 
FOCUS FOR THE EXTENDED PERIOD WILL BE ON MID-WEEK AS THE NEXT  
WEATHER SYSTEM IMPACTS THE REGION. SURFACE LOW PRESSURE IS EXPECTED  
TO DEVELOP OVER THE NORTHERN GULF AND THEN LIFT NORTHEAST, PASSING  
NEAR/ALONG THE SOUTHEAST COAST WEDNESDAY INTO WEDNESDAY NIGHT. AMPLE  
FORCING FOR ASCENT ALONG WITH PWATS RISING TO WELL OVER AN INCH WILL  
RESULT IN A FAIRLY WET DAY WITH WIDESPREAD SHOWERS CURRENTLY  
FORECAST. THIS SYSTEM HAS THE POTENTIAL TO BRING 1-2 INCHES OF RAIN  
TO THE AREA. INSTABILITY PROGS ARE PRETTY MEAGER, SO NO THUNDER IS  
MENTIONED IN THE FORECAST AT THIS TIME. RAIN CHANCES SHOULD DECREASE  
WEDNESDAY NIGHT.  
 
THE AFOREMENTIONED LOW WILL LIFT AWAY FROM THE AREA ON THURSDAY,  
ALLOWING CHILLY AND DRY HIGH PRESSURE TO BUILD FOR LATE WEEK.  
TEMPERATURES WILL BE NOTABLY COOLER, WITH LOWS DIPPING WELL INTO THE  
20S. WILL NEED TO MONITOR THE POTENTIAL FOR A COLD WEATHER ADVISORY  
(WIND CHILL 20F OR COLDER) THURSDAY NIGHT.  
 

 
   
AVIATION /06Z SUNDAY THROUGH THURSDAY/
 
 
PRIOR TO THE 6Z TAFS, KCLX VAD PROFILE DETECTED SOUTH WINDS AT  
50 KTS AT 1 KFT, EACH TAF WILL BE INITIALIZED WITH LLWS. IR  
SATELLITE ALONG WITH SURFACE BASED OBSERVATIONS INDICATED MVFR  
TO IFR CEILINGS ACROSS KCHS AND KJZI. KSAV WAS UNDER A PATCH OF  
MID-LEVEL CEILINGS WITH FEW TO SCT IFR BASED CLOUDS, EXPECTED TO  
REMAIN UNTIL 9Z. MOS AND RECENT RUNS OF THE HRRR INDICATES THAT  
AT LEAST MVFR CEILINGS WILL REMAIN OVER THE TERMINALS THROUGH  
DAYBREAK. GUIDANCE SHOWS THAT SOUTHWEST WINDS WILL CONTINUE TO  
STRENGTHEN AS A COLD FRONT APPROACHES FROM THE WEST. WINDS ARE  
TIMED TO PEAK DURING THE MID TO LATE MORNING HOURS, GUSTS AROUND  
40 KTS. BASED ON RADAR TRENDS AND HIGH RESOLUTION GUIDANCE, A  
SOLID LINE OF SHOWERS WITH EMBEDDED THUNDERSTORMS IS TIMED TO  
PUSH ACROSS THE TERMINALS BETWEEN 14-18Z, HIGHLIGHTED WITH  
TEMPOS. AFTER THE LINE OF CONVECTION AND COLD FRONT, WINDS ARE  
FORECAST TO VEER FROM THE WEST BETWEEN 10 TO 15 KTS WITH GUSTS  
AROUND 20 KTS. CLOUD COVER SHOULD DECREASE THROUGH THE REST OF  
THE AFTERNOON AND EVENING.  
 
EXTENDED AVIATION OUTLOOK: VFR WILL RETURN FOR MONDAY AND TUESDAY.  
FLIGHT RESTRICTIONS ARE POSSIBLE WEDNESDAY INTO WEDNESDAY NIGHT AS A  
LOW PRESSURE SYSTEM PASSES ACROSS THE REGION.  
 

 
   
MARINE
 
 
WE HAVE CANCELLED THE DENSE FOG ADVISORY FOR THE NEARSHORE  
WATERS OF GEORGIA AND OFF THE LOWER SOUTH CAROLINA COAST.  
HOWEVER, FOG IS SPREADING NORTH INTO THE CHARLESTON COUNTY  
WATERS, INCLUDING CHARLESTON HARBOR. WE HAVE INCREASED THE  
COVERAGE OF FOG TO A QUALIFIER OF "AREAS", BUT ANY VISIBILITIES  
OF LESS THAN 1 NM LOOKS TO BE TOO LIMITED IN COVERAGE TO HOIST A  
DENSE FOG ADVISORY. AS WINDS INCREASE OVERNIGHT DUE TO A  
TIGHTENING OF THE PRESSURE GRADIENT AND BOTH THE 850 MB AND 925  
MB WINDS APPROACH 40 KT, THE FOG WILL COMPLETELY DISSIPATE.  
THOSE SAME WINDS HOWEVER WILL RESULT IN STRENGTHENING SURFACE  
WINDS AND THE RESULTING CLIMBING SEAS. SMALL CRAFT ADVISORIES  
ARE THEREFORE IN EFFECT FOR ALL WATERS.  
 
SUNDAY: A COLD FRONT WILL BE APPROACHING THE WATERS FROM THE  
WEST AND SWEEP ACROSS THE MARINE ZONES IN THE EARLY AFTERNOON.  
OUT AHEAD OF THE COLD FRONT, THE CORE OF THE 60 KT JET WILL BE  
JUST OFF THE SC COAST. SOME HIGH RES GUIDANCE IS INDICATING THE  
POSSIBILITY OF STORM FORCE GUSTS, BUT GIVEN THE TEMPERATURES OF  
THE SHELF WATERS HAVE OPTED FOR A GALE WARNING WITH GUSTS  
PEAKING AT 45 KT. SEAS WILL ALSO BE DANGEROUS SUNDAY AND PEAK 8  
TO 12 FT. A HIGH SURF ADVISORY WAS CONSIDERED, BUT WE OPTED TO  
HOLD FOR NOW GIVEN THE COASTLINE PARALLEL WAVE ENERGY. HOWEVER  
THIS MIGHT NEED TO BE RE-EVALUATED.  
 
MONDAY THROUGH THURSDAY: MARINE CONDITIONS WILL SUBSIDE ON  
MONDAY AS HIGH PRESSURE EXPANDS ACROSS THE AREA AND THE PRESSURE  
GRADIENT RELAXES. WINDS WILL TURN NORTHERLY AND EVENTUALLY MORE  
NORTHEASTERLY WITH NO CONCERNS THROUGH TUESDAY. A LOW PRESSURE  
SYSTEM IS EXPECTED TO IMPACT THE REGION WEDNESDAY INTO WEDNESDAY  
NIGHT WHICH WILL BRING THE NEXT CHANCE FOR SMALL CRAFT  
ADVISORIES. WINDS COULD STAY ELEVATED ON THURSDAY BEHIND THE  
SYSTEM AS HIGH PRESSURE BUILDS INTO THE AREA.  
 
HIGH SURF: GIVEN THAT SEAS WILL BUILD TO AS HIGH AS 6-10 FEET ON  
THE NEARSHORE WATERS ON SUNDAY, WE MIGHT REQUIRE A HIGH SURF  
ADVISORY, ESPECIALLY FOR CHARLESTON COUNTY, WHERE THE FLOW IS  
MORE ONSHORE THAN FURTHER SOUTH, WHERE IT IS MORE PARALLEL TO  
THE COAST.  
 

 
   
CHS WATCHES/WARNINGS/ADVISORIES
 
 
GA...WIND ADVISORY FROM 5 AM EARLY THIS MORNING TO 6 PM EST THIS  
EVENING FOR GAZ087-088-099>101-114>119-137>141.  
SC...WIND ADVISORY FROM 5 AM EARLY THIS MORNING TO 6 PM EST THIS  
EVENING FOR SCZ040-042>045-047>052.  
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR AMZ330-  
350-352-354-374.  
GALE WARNING FROM 7 AM THIS MORNING TO 3 PM EST THIS AFTERNOON  
FOR AMZ330.  
GALE WARNING FROM 7 AM THIS MORNING TO 6 PM EST THIS EVENING  
FOR AMZ350-352-354-374.  
 

 
 

 
 
NEAR TERM...NED  
SHORT TERM...ETM/HAINES  
LONG TERM...ETM  
AVIATION...NED  
MARINE...  
 
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