521  
FXUS62 KCAE 060237  
AFDCAE  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE COLUMBIA SC  
1037 PM EDT SUN JUL 5 2020  
   
SYNOPSIS
 
 
MOISTURE WILL RETURN TO THE AREA MONDAY AS AN UPPER TROUGH ALONG  
THE GULF COAST SLOWLY LIFTS NORTHEASTWARD THROUGH MID WEEK AND A  
WEAK FRONTAL BOUNDARY STALLS OVER THE REGION. THIS WILL BRING  
WITH INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS INTO THE  
MIDDLE OF THE WEEK WITH HEAVY RAIN POSSIBLE. THE UPPER TROUGH  
MAY PUSH OFFSHORE BY THE WEEKEND.  
 

 
   
NEAR TERM /UNTIL 6 AM MONDAY MORNING/
 
 
THE UPPER TROUGH ALONG THE GULF COAST WILL BEGIN TO SLOWLY LIFT  
NORTHEASTWARD. AHEAD OF THAT LIFTING TROUGH, A GOOD SURGE OF  
MOISTURE WILL BEGIN PUSHING NORTHWARD INTO OUR AREA THROUGH THE  
NIGHT. PWATS WILL RISE TO ALMOST 2 INCHES BY 12Z ACROSS THE CSRA  
AND SOUTHERN MIDLANDS WITH A GRADIENT TO LOWER VALUES NORTHWARD.  
CLOUD COVER SHOULD INCREASE TOWARDS MORNING. LIMITED INSTABILITY,  
AND ONLY EXPECTING ISOLATED TO SCATTERED SHOWERS TO REDEVELOP  
CLOSER TO SUNRISE ACROSS THE SOUTHERN THIRD OF THE FORECAST  
AREA. OVERNIGHT LOWS WILL BE MILD AND LIMITED BY THE INCREASING  
CLOUD COVER AND SHOULD BE IN THE LOWER TO MID 70S.  
 

 
   
SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/
 
 
WEAK HIGH PRESSURE RIDGING OVER THE AREA WILL CONTINUE TO ERODE  
MONDAY AS THE BOUNDARY THAT HAS REMAINED TO THE SOUTH CONTINUES  
TO LIFT NORTHWARD AS A WARM FRONT. A STEADY INCREASE IN  
MOISTURE AND ISENTROPIC LIFT WILL LEAD TO THE POSSIBILITY OF  
SHOWERS OVER THE CSRA EARLY MONDAY MORNING. WITH MID-LEVEL FLOW  
OUT OF THE SW, EXPECT SIGNIFICANT GULF MOISTURE TO MOVE OVER THE  
AREA WITH PWATS QUICKLY CLIMBING TO NEAR 2 INCHES BY MONDAY  
AFTERNOON OVER THE ENTIRE FORECAST AREA. INSTABILITY MAY BE A  
BIT MORE LIMITED BUT STILL EXPECT THUNDERSTORMS OVER THE AREA  
THROUGH THE AFTERNOON WHICH WILL LIKELY PRODUCE LOCALLY HEAVY  
RAIN. SOME STRONG DOWNDRAFTS WILL BE POSSIBLE WITH STORMS AS  
SOME DRY AIR REMAINS IN THE MID-LEVELS, ESPECIALLY FOR CENTRAL  
AND NORTHERN SC BUT OVERALL THE SEVERE WEATHER THREAT REMAINS  
LOW. HIGHS WILL REMAIN BELOW AVERAGE WITH INCREASED CLOUDS,  
REMAINING MOSTLY IN THE MID AND UPPER 80S. SHOWERS WILL CONTINUE  
TO BE POSSIBLE OVERNIGHT WITH POSITIVE VORTICITY ADVECTION FROM  
A 500MB TROUGH THAT WILL STILL BE TO THE WEST.  
 
MOISTURE TRANSPORT WILL CONTINUE TO INCREASE TUESDAY WITH PWATS  
UP NEAR 2.5 INCHES, WHICH BASED ON UPPER AIR CLIMATOLOGY, WOULD  
BE NEAR RECORD FOR EARLY JULY. WITH SURFACE LOW PRESSURE  
DEVELOPING AND UPPER LEVEL ENERGY ASSOCIATED WITH THIS TROUGH  
WHICH MODELS INDICATE WILL BECOME NEGATIVELY TILTED, EXPECT  
SIGNIFICANT RAIN DURING THE DAY TUESDAY WITH THE POTENTIAL FOR  
SOME LOCALIZED FLOODING. THE GOOD NEWS IS THAT STRONG  
THUNDERSTORM DEVELOPMENT WILL BE LIMITED BE A LACK OF  
INSTABILITY WITH TEMPERATURES RISING INTO THE LOW 80S.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/
 
 
THERE IS SOME QUESTION AS TO THE PROGRESSION OF THE LOW PRESSURE  
SYSTEM AFTER MIDWEEK. TROPICAL MOISTURE WILL REMAIN IN THE AREA  
AT LEAST THROUGH WEDNESDAY BUT AGAIN HEAVY RAIN WILL LIKELY  
BE THE MAIN THREAT AS INSTABILITY WILL BE SEVERELY LIMITED.  
TEMPERATURES REMAIN WELL BELOW AVERAGE IN THE MID 80S. ECMWF  
SUPPORTS UPPER LEVEL LOW DEVELOPMENT WHICH WOULD WORK TO CUT  
OFF THE STEERING FLOW AND WOULD KEEP SURFACE LOW PRESSURE AT  
LEAST NEAR THE AREA BUT LIKELY CLOSER TO THE COAST. THIS SYSTEM  
DOES HAVE THE POTENTIAL FOR TROPICAL DEVELOPMENT ACCORDING TO  
THE NHC BUT SHOULD CONTINUE TO MOVE AWAY FROM OUR AREA. THERE  
WILL BE LESS OF A CHANCE FOR SHOWERS AND STORMS WITH SOME  
SUBSIDENCE ON THE WEST SIDE OF THE LOW AND MAYBE SOME WEAK  
RIDGING DEVELOPING WHICH AT THE VERY LEAST WILL BRING  
TEMPERATURES CLOSER TO NORMAL.  
 
AS THIS UPPER TROUGH DEPARTS LATER IN THE WEEK, LINGERING  
MOISTURE WILL CONTINUE TO SUPPORT AT LEAST DIURNAL THUNDERSTORM  
DEVELOPMENT. A DRIER PATTERN MAY BE POSSIBLE LATER IN THE  
WEEKEND WITH A STRENGTHENING RIDGE IN THE SOUTHWESTERN US AND NW  
FLOW FOR OUR AREA WHICH WOULD KEEP SIGNIFICANT MOISTURE AT BAY  
WITH TEMPERATURES NEAR NORMAL.  
 

 
   
AVIATION /03Z MONDAY THROUGH FRIDAY/
 
 
VFR CONDITIONS TO START, THEN CEILINGS LOWERING TO MVFR OR IFR  
LATE TONIGHT IN THE CSRA. THE LOW CEILINGS MAY SPREAD INTO  
CENTRAL SC DURING THE MORNING.  
 
MAINLY CLEAR SKY WITH VFR CONDITIONS THROUGH AT 06Z. A WARM  
FRONT WILL MOVE INTO THE AREA FROM GA LATE TONIGHT AND EARLY  
MONDAY MORNING. EXPECT CEILINGS TO LOWER FROM SOUTH TO NORTH  
THROUGH 15Z WITH RESTRICTIONS MOST LIKELY NEAR AGS/DNL. EXPECT  
LOW CLOUDS TO MIX OUT AFTER 15Z WITH SCATTERED TO NUMEROUS  
SHOWERS DEVELOP DUE TO INSENTROPIC LIFT AND MOISTURE FLUX.  
RESTRICTIONS AT TIMES POSSIBLE. AIR MASS BECOMING UNSTABLE SO A  
FEW THUNDERSTORMS POSSIBLE MAINLY IN THE AFTERNOON.  
   
EXTENDED AVIATION OUTLOOK
 
INCREASING MOISTURE INTO EARLY  
NEXT WEEK MAY LEAD TO RESTRICTIONS AT TIMES IN SHOWERS AND  
THUNDERSTORMS AND MORNING FOG/STRATUS.  
 

 
   
CAE WATCHES/WARNINGS/ADVISORIES
 
 
GA...NONE.  
SC...NONE.  
 

 
 

 
 
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