047  
FXUS62 KCHS 290135  
AFDCHS  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHARLESTON SC  
935 PM EDT MON JUL 28 2025  
   
SYNOPSIS  
 
ATLANTIC HIGH PRESSURE WILL PREVAIL EARLY THIS WEEK, WHILE A  
TROUGH OF LOW PRESSURE RESIDES INLAND. A COLD FRONT COULD  
APPROACH THE REGION LATE IN THE WEEK.  
 
 
   
NEAR TERM /UNTIL 6 AM TUESDAY MORNING/  
 
TONIGHT: A STRONG UPPER-LVL RIDGE SITUATED OVER ARKLATEX REGION  
CONTINUES TO SHIFT WESTWARD, WHILE A SFC LEE TROUGH REMAINS IN PLACE  
INLAND. WEAK VORTICITY ASSOCIATED WITHIN NORTHWESTERLY FLOW ALOFT IN  
THE AFOREMENTIONED UPPER-LVL RIDGE WILL ALLOW FOR MID-LVL MOISTURE  
TO ADVECT INTO THE REGION, AND PROMOTE SCATTERED SHOWERS AND  
THUNDERSTORMS INTO LATE EVENING HOURS, PRIMARILY NEAR THE I-95  
CORRIDOR WHERE CONVECTIVE BOUNDARY/OUTFLOW INTERACTIONS CONTINUE  
DURING THE NEXT 1-2 HOURS. ALTHOUGH SHEAR IS WEAK, SBCAPE  
AROUND 4000-4500 J/KG, LOW-LVL LAPSE RATES AROUND 7 C/KM, AND  
DCAPE NEAR 1200-1500 J/KG SUGGEST AN ISOLATED STRONG AND/OR  
BRIEFLY SEVERE THUNDERSTORM BEING POSSIBLE. SLOW STORM MOTIONS  
AND AMPLE MOISTURE (PWATS NEAR 2.00 TO 2.25 INCHES) ALSO SUGGEST  
A POTENTIAL FOR LOCALIZED HEAVY RAINFALL LEADING TO MINOR FLOODING  
BEFORE ACTIVITY WANES LATE EVENING.  
 
THE THREAT FOR EXCESSIVE HEAT HAS COME TO AN END WITH SUNSET, BUT  
CONDITIONS WILL REMAIN WARM AND MUGGY OVERNIGHT. REMAINING CONVECTION  
SHOULD DISSIPATE BY AROUND MIDNIGHT, SETTING UP RAIN-FREE CONDITIONS  
FOR A MAJORITY OF THE LOCAL AREA DURING THE SECOND HALF OF THE  
NIGHT. CONDITIONS WILL REMAIN WARM AND MUGGY LATE, WITH TEMPERATURES  
ONLY DIPPING INTO THE MID-UPPER 70S INLAND TO AROUND 80 ALONG  
THE COASTAL CORRIDOR, INCLUDING DOWNTOWN CHARLESTON.  
 
 
   
SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/  
 
THE MID-LEVELS WILL CONSIST OF OUR REGION INITIALLY BEING ON THE  
EASTERN PERIPHERY OF AN EXPANSIVE RIDGE. THOUGH, IT'LL BUILD BACK  
OVER OUR AREA BY THURSDAY. AT THE SURFACE, HIGH PRESSURE WILL BE IN  
THE ATLANTIC WITH TROUGHING INLAND.  
 
EXPECT HOT AND HUMID CONDITIONS. TEMPERATURES WILL BE ABOVE NORMAL  
WITH DEWPOINTS INTO THE MID TO UPPER 70S. THIS WILL EQUATE TO HEAT  
INDICES REACHING HEAT ADVISORY CRITERIA OF 108-112F ON TUESDAY,  
SLIGHTLY HIGHER IN SOME SPOTS. THEREFORE, WE HAVE A HEAT ADVISORY IN  
EFFECT. THERE IS THE POTENTIAL FOR THIS HAPPENING AGAIN ON WEDNESDAY  
AND THURSDAY. HOWEVER, CONVECTION COULD COOL TEMPERATURES BEFORE THE  
HEAT PERSISTS TOO LONG BOTH OF THOSE DAYS.  
 
THE MOST ACTIVE DAY OF THE SET APPEARS TO BE ON TUESDAY WITH BETTER  
FORCING IN PLAY. NUMEROUS SHOWERS AND THUNDERSTORMS FORECAST TO  
DEVELOP BY MID TO LATE AFTERNOON. POPS FOR WEDNESDAY AND THURSDAY  
ARE MORE IN THE SCATTERED RANGE (30-50%). GIVEN THE AIRMASS IN  
PLACE, A COUPLE STRONGER STORMS WITH DAMAGING WIND GUSTS WILL BE  
POSSIBLE DESPITE RELATIVELY WEAK SHEAR, FOLLOWED BY LOCALLY HEAVY  
RAINFALL.  
 
 
   
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/  
 
THERE WILL FINALLY BE REPRIEVE FROM THE OPPRESSIVE HEAT LATE WEEK  
AND OVER THE WEEKEND AS MID LEVEL HEIGHTS FALL IN RESPONSE TO A  
TROUGH OVER THE NORTHEAST AND MID-ATLANTIC. SOME TIMING  
INCONSISTENCIES EXIST, BUT CONSENSUS SHOWS A COLD FRONT MOVING INTO  
THE AREA AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL BRING  
COOLER TEMPERATURES AND INCREASED RAIN CHANCES. THE FRONT COULD  
STALL IN THE VICINITY THROUGH EARLY NEXT WEEK.  
 
 
   
AVIATION /02Z TUESDAY THROUGH SATURDAY/  
 
TEMPO MVFR CONDITIONS ARE POSSIBLE AT SAV THROUGH 02Z TUESDAY AS  
SHOWERS AND/OR THUNDERSTORMS SHIFT ACROSS THE TERMINAL AND WEAKEN.  
OTHERWISE, VFR CONDITIONS WILL PREVAIL CHS/JZI/SAV TERMINALS THROUGH  
AT LEAST LATE MORNING TUESDAY. FLIGHT RESTRICTIONS POTENTIALLY  
RETURN AT ALL TERMINALS TUESDAY AFTERNOON WITH SHOWERS AND  
THUNDERSTORMS DEVELOPING ACROSS THE AREA. HOWEVER, GREATER CHANCES  
APPEAR TO OCCUR AWAY FROM THE IMMEDIATE COAST, AND CLOSER TO CHS/SAV  
TERMINALS MID AFTERNOON. FOR THIS REASON, VCTS HAS BEEN INTRODUCED  
AT CHS/SAV TERMINALS FROM 19-23Z TUESDAY.  
 
EXTENDED AVIATION FORECAST: MAINLY VFR. EXPECT BRIEF FLIGHT  
RESTRICTIONS IN AFTERNOON/EVENING SHOWERS/THUNDERSTORMS.  
 
 
   
MARINE  
 
TONIGHT: OUTSIDE OF CONVECTION AND/OR A WIND SHIFT (OUTFLOW)  
OCCURRING ALONG THE COAST THIS EVENING, GENERALLY EXPECT SOUTH-  
SOUTHWESTERLY WINDS BETWEEN 5 TO 10 KT BETWEEN HIGH PRESSURE  
OFFSHORE AND WEAK TROUGHING INLAND. SEAS WILL RANGE FROM 1-2 FT  
OVERNIGHT.  
 
EXTENDED MARINE: THE COASTAL WATERS WILL BE SANDWICHED BETWEEN HIGH  
PRESSURE IN THE ATLANTIC AND COASTAL TROUGHING INLAND MOST OF THIS  
WEEK. THIS WILL YIELD A TYPICAL SUMMERTIME WIND PATTERN.  
EACH DAY, EXPECT BACKING WINDS WITH THE FORMATION OF THE AFTERNOON  
SEA BREEZE. THE HIGHEST GUSTS WILL BE ALONG THE LAND/SEA INTERFACE  
AND ACROSS CHARLESTON HARBOR (WITH ITS PASSAGE). EACH NIGHT, EXPECT  
VEERING OF THE WINDS AS A NOCTURNAL JET SETS UP CLOSE TO SHORE. SEAS  
WILL AVERAGE 1-3 FEET. A COLD FRONT IS EXPECTED TO MOVE INTO THE  
REGION LATE THIS WEEK AND INTO THE WEEKEND. WINDS MAY TURN TO THE  
NORTH AND EVENTUALLY NORTHEAST, AND INCREASE. BUT THESE DETAILS WILL  
NEED TO BE IRONED OUT IN FUTURE FORECASTS.
 
   
CLIMATE  
 
RECORD HIGH TEMPERATURES:  
 
JULY 28:  
KCHS: 101/1949  
KCXM: 100/1936  
KSAV: 102/1949  
 
RECORD HIGH MINIMUM TEMPERATURES:  
 
JULY 28:  
KCHS: 80/2016  
KCXM: 83/1999  
KSAV: 81/1878  
 
JULY 29:  
KCHS: 80/2016  
KSAV: 82/1878  
 
JULY 30:  
KCHS: 81/2016  
KCXM: 83/2016  
KSAV: 81/1878  
 
JULY 31:  
KCHS: 80/2022  
KCXM: 84/2016  
KSAV: 80/2010  
 
AUGUST 1:  
KCHS: 81/1999  
KSAV: 79/2020  
 
AUGUST 2:  
KCHS: 79/2022  
 
 
   
CHS WATCHES/WARNINGS/ADVISORIES  
 
GA...HEAT ADVISORY FROM 11 AM TO 8 PM EDT TUESDAY FOR GAZ087-088-  
099>101-114>119-137>141.  
SC...HEAT ADVISORY FROM 11 AM TO 8 PM EDT TUESDAY FOR SCZ040-  
042>045-047>052.  
MARINE...NONE.  
 
 
 
 
 
NEAR TERM...DPB  
SHORT TERM...  
LONG TERM...  
AVIATION...DPB  
MARINE...DPB  
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