428  
FXUS62 KCHS 271034  
AFDCHS  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHARLESTON SC  
634 AM EDT TUE JUN 27 2017  
   
SYNOPSIS
 
 
A STATIONARY FRONT WILL LINGER OFF THE COAST TODAY. HIGH  
PRESSURE WILL PAST NORTH OF THE REGION WEDNESDAY, THEN SHIFT  
INTO THE ATLANTIC THURSDAY. A SURFACE TROUGH WILL DEVELOP INLAND  
ON FRIDAY AND PREVAIL INTO THE WEEKEND.  
 

 
   
NEAR TERM /UNTIL 6 PM THIS EVENING/
 
 
INCREASED POPS OFF THE GEORGIA COAST WHERE CONVECTION IS  
DEVELOPING NEAR THE STATIONARY FRONT. MADE MINOR CHANGES TO SKY  
COVER AND HOURLY TEMPERATURES PER GOING TRENDS. THE REST OF THE  
FORECAST LOOKS GOOD.  
 
A WEAK STATIONARY FRONT EXTENDS ROUGHLY ALONG A KTVI-KAYS-  
COX-SHELLMAN BLUFF-TO ~20 NM EAST OF KHXD PER 27/07Z SURFACE  
ANALYSIS. THE FRONT WILL MEANDER SLOWLY SOUTH TODAY AS HIGH  
PRESSURE PROPAGATES EAST ACROSS THE OHIO VALLEY. A MODEST SEA  
BREEZE CIRCULATION WILL BEGIN TO TREK INLAND LATER THIS  
AFTERNOON AND WILL BE THE PRIMARY FOCUS FOR ISOLATED TO  
SCATTERED SHOWERS/TSTMS. SOME CONVECTION COULD POP ALONG  
COASTAL PORTIONS OF MCINTOSH AND LIBERTY COUNTIES LATER THIS  
MORNING IN THE VICINITY OF THE FRONT, BUT THE BULK OF THE  
CONVECTION SHOULD HOLD OFF UNTIL LATER THIS AFTERNOON. 20-30%  
POPS LOOK REASONABLE FOR MOST AREAS TODAY WITH UP TO 40% ACROSS  
MCINTOSH COUNTY.  
 
HIGHS WILL RANGE FROM THE UPPER 80S INLAND TO THE LOWER 80S AT  
THE BEACHES WHERE ONSHORE WINDS WILL TEMPER CONDITIONS. THERE  
ARE SIGNALS THAT A THICK CIRROSTRATUS DECK WILL DEVELOP AFTER  
SUNRISE, BUT THIS SHOULD GRADUALLY MOVE EAST AND BE REPLACED  
WITH A CUMULUS FIELD AHEAD OF THE SEA BREEZE BY PEAK HEATING.  
 

 
   
SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/
 
 
TONIGHT: ANY RESIDUAL CONVECTION WILL QUICKLY DISSIPATE AFTER  
SUNSET. DRY CONDITIONS WILL PREVAIL THROUGH THE NIGHT. LOWS WILL  
RANGE FROM THE MID 60S ACROSS INTERIOR SOUTHEAST SOUTH CAROLINA  
TO THE MID 70S AT THE BEACHES.  
 
WEDNESDAY THROUGH FRIDAY: WE'LL GET A SHORT BREAK FROM THE TYPICAL  
SUMMERTIME HEAT AND HUMIDITY WEDNESDAY BEFORE IT SLOWLY RETURN  
THURSDAY. SHOWER AND T- STORM CHANCES ARE BELOW AVERAGE  
WEDNESDAY, THEN CREEPING UP THURSDAY AND FRIDAY.  
 
THE BROAD TROUGH IN THE EAST LIFTS OUT AND GIVES WAY TO BUILDING  
HEIGHTS ALOFT FROM A BUILDING SUB-TROPICAL RIDGE CENTERED NEAR THE  
NW BAHAMAS WEDNESDAY THAT BECOMES POSITIONED ABOUT MIDWAY BETWEEN  
FLORIDA AND BERMUDA THURSDAY INTO FRIDAY. MOISTURE IS DEFINITELY  
LACKING WEDNESDAY, WITH PWAT'S STRUGGLING TO GET ABOVE 1" ACROSS OUR  
NORTHERN ZONES, OR ROUGHLY 2 STANDARD DEVIATIONS BELOW NORMAL. THIS  
IS DUE TO DRY HIGH PRESSURE TO OUR NORTH HOLDING THE MOISTURE TO OUR  
SOUTH. THE HIGH IS FORECASTED TO MOVE OFFSHORE INTO THE ATLANTIC  
THURSDAY, ALLOWING SE FLOW TO PUMP IN HIGHER PWATS ACROSS OUR AREA,  
MUCH CLOSER TO NORMAL FOR THIS TIME OF YEAR. THE SEA BREEZE IS THE  
MAIN DRIVER OF ANY DIURNAL CONVECTION DURING THIS TIME, AND THIS  
SUPPORTS AT MOST ISOLATED COVERAGE ACROSS INTERIOR SE GA WEDNESDAY.  
WITH BETTER MOISTURE THURSDAY WE ARE FORECASTING 30-40% POPS, MAINLY  
FOR SE GA. POPS TAPER NORTHWARDS INTO SE SC WHERE ENOUGH DRY AND  
SUBSIDENCE ALOFT MAY REMAIN IN PLACE TO ONLY ALLOW AFTERNOON CU  
DEVELOPMENT. BUT BY FRIDAY THE MOISTURE WILL BE IN PLACE ACROSS OUR  
ENTIRE AREA. WITH TEMPERATURES TOPPING OUT NEAR 90 DEGREES AND  
PLENTY OF INSTABILITY IN PLACE, POPS RANGE FROM 40-50%. ISOLATED  
SEVERE STORMS WITH DAMAGING WINDS ARE POSSIBLE.  
 

 
   
LONG TERM /FRIDAY NIGHT THROUGH MONDAY/
 
 
NEARLY ZONAL FLOW WILL PERSIST ALOFT WITH SURFACE HIGH PRESSURE IN  
THE ATLANTIC. SOUTHERLY FLOW AROUND THE HIGH WILL ADVECT PLENTY OF  
MOISTURE INTO THE SOUTHEAST AS AN INLAND TROUGH DEVELOPS THIS  
WEEKEND. THE RESULT WILL BE THE TYPICAL SUMMERTIME  
SHOWER/THUNDERSTORM PATTERN WITH THE COVERAGE AND INTENSITY TRENDING  
UPWARDS EACH DAY INTO THE WEEKEND.  
 

 
   
AVIATION /12Z TUESDAY THROUGH SATURDAY/
 
 
VFR. A FEW SHOWERS/TSTMS COULD MEANDER AROUND KSAV MID  
AFTERNOON, BUT IMPACT PROBABILITIES ARE TOO LOW TO JUSTIFY A  
MENTION AT THIS TIME.  
 
EXTENDED AVIATION OUTLOOK: VFR WEDNESDAY. BRIEF FLIGHT RESTRICTIONS  
ARE POSSIBLE IN AFTERNOON/EVENING SHRA/TSRA FOR KSAV THURSDAY, THEN  
BOTH KCSH AND KSAV FRIDAY AND SATURDAY.  
 

 
   
MARINE
 
 
TODAY AND TONIGHT: EASTERLY WINDS WILL ENCOMPASS THE ENTIRE  
MARINE AREA LATER TODAY AS HIGH PRESSURE REMAINS WELL TO THE  
NORTH AND A WEAK STATIONARY FRONT LINGERS TO THE SOUTH. WINDS  
WILL REMAIN LESS THAN 10 KT WITH SEAS 1-2 FT. EXPECT SIMILAR  
CONDITIONS FOR THE OVERNIGHT HOURS.  
 
WEDNESDAY THROUGH SATURDAY: HIGH PRESSURE CENTERED TO OUR NORTH  
WEDNESDAY WILL SHIFT OFFSHORE THURSDAY AND PREVAIL IN THE ATLANTIC  
INTO THE WEEKEND. EASTERLY WINDS ~15 KT ON WEDNESDAY WILL VEER TO  
THE SE THURSDAY AND EASE A FEW KT AS COUNTER-CLOCKWISE FLOW DEVELOPS  
AROUND THE HIGH, PREVAILING THROUGH THE END OF THE WEEK. SEA BREEZE  
CIRCULATIONS WILL GIVE A BOOST TO THE WINDS EACH DAY WITH  
SHOWER/THUNDERSTORM CHANCES INCREASING INTO THE WEEKEND. SEAS WILL  
AVERAGE NO GREATER THAN 2-4 FT.  
 

 
   
CHS WATCHES/WARNINGS/ADVISORIES
 
 
GA...NONE.  
SC...NONE.  
MARINE...NONE.  
 

 
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SC Page
The Nexlab GA Page Main Text Page