201  
FXUS64 KSHV 201549 AAA  
AFDSHV  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE SHREVEPORT LA  
1049 AM CDT FRI SEP 20 2019  
 
   
UPDATE
 
 
WHAT REMAINS OF IMELDA THIS MORNING HAS GENERALLY LOST A CLOSED  
CIRCULATION AT THIS POINT, BUT THE REMNANT AREA OF LOW PRESSURE IS  
MORE OR LESS CENTERED TO OUR WEST IN NORTH-CENTRAL TX. MOISTURE  
ADVECTION AND CONVERGENCE TO THE EAST OF THE LOW IS STILL  
RELATIVELY IMPRESSIVE AND DRIVING LOCALLY HEAVY RAINS AND  
EMBEDDED THUNDERSTORMS ACROSS EXTREME SE OK, FAR NE TX, AND VERY  
SOUTHWESTERN PORTIONS OF SW AR. RAINFALL RATES HAVE BEEN RUNNING  
UP TO 2 TO 3 INCHES PER HOUR IN SPOTS THERE RECENTLY, MAINLY OVER  
MCCURTAIN COUNTY, AND WE ARE CLOSELY MONITORING THE HEAVY RAIN  
SITUATION UP THERE. SO FAR WE HAVE NOT HEARD OF EXCESSIVE RAINFALL  
ISSUES (EVEN THOUGH THERE ARE LOCALIZED TOTALS NOW OVER 4 INCHES)  
AND ARE HOPING SHORT TERM MODEL TRENDS SHOWING THE HEAVIEST RAIN  
SLACKENING THERE OVER THE COURSE OF THE NEXT SEVERAL HOURS PROVE  
CORRECT. IF THE LATTER DOES NOT HAPPEN WE WILL LIKELY HAVE TO  
START ISSUING FLASH FLOOD WARNINGS.  
 
OTHERWISE, EXPECT THE MOISTURE RICH SOUTHERLY FLOW IN A HIGH  
PRECIPITABLE WATER ENVIRONMENT TO DRIVE SCATTERED TO NUMEROUS  
SHOWERS AND ISOLATED THUNDERSTORMS ELSEWHERE IN THE FORECAST AREA  
AS WE GO THROUGH THE AFTERNOON. FORTUNATELY, THIS ACTIVITY WILL BE  
MOVING AND NOT PRONE TO PRODUCING A FLOODING THREAT. ALL THE  
CLOUDS AND PRECIPITATION WILL KEEP TEMPERATURES BELOW NORMAL WITH  
HIGHS GENERALLY EXPECTED TO RANGE FROM 80 TO 85 DEGREES IN MOST  
LOCATIONS. /50/  
 

 
   
PREV DISCUSSION
 
/ISSUED 728 AM CDT FRI SEP 20 2019/  
 
AVIATION...  
 
A MIX BAG OF ALL FLIGHT CATEGORIES THIS MORNING AS A LARGE AREA OF  
PRECIPITATION MOVES ACROSS THE REGION IN CONNECTION WITH THE  
REMNANTS OF IMELDA. CEILINGS TO GRADUALLY IMPROVE TO VFR BY  
20/18Z BUT ADDITIONAL CONVECTION IS EXPECTED DURING THE AFTERNOON,  
WHICH COULD RESULT IN PERIODS OF LOWER FLIGHT CATEGORIES.  
EVENTUALLY, MOST OF THE PRECIPITATION WILL EXIT THE REGION BY  
21/00Z WITH SOME LOW CIGS MOVING INTO PORTIONS OF THE REGION  
DURING THE OVERNIGHT PERIOD. WINDS WILL REMAIN EAST TO SOUTHEAST  
AROUND 10 KNOTS INCREASING TO 10 TO 15 KNOTS TODAY WITH GUSTS TO  
25 KNOTS ACROSS MAINLY EAST TEXAS TERMINALS BEFORE DECREASING  
AFTER SUNSET. /20/  
 
PREV DISCUSSION... /ISSUED 434 AM CDT FRI SEP 20 2019/  
 
SHORT TERM.../TODAY THROUGH SATURDAY NIGHT/  
 
CURRENT REGIONAL RADAR SHOWS A LARGE AREA OF PRECIPITATION MOVING  
NORTHEAST THROUGH EAST TX AND NW LOUISIANA THIS MORNING IN  
ASSOCIATION WITH THE REMNANTS OF IMELDA. THIS PRECIPITATION WILL  
CONTINUE TO SPREAD NORTHEAST INTO THE REMAINDER OF OUR LOUISIANA  
PARISHES THIS MORNING AS WELL AS SE OKLAHOMA AND SW ARKANSAS.  
ADDITIONAL CONVECTION WILL DEVELOP ACROSS THE REGION TODAY AS THE  
REMNANTS OF IMELDA, NOW AN OPEN WAVE, CONTINUES TO MOVE NORTHWARD  
OUT OF THE REGION. FORTUNATELY FOR US, IT APPEARS WE WILL NOT SEE  
THE RAINFALL AMOUNTS EXPECTED EARLIER WITH THIS SYSTEM. AN  
ADDITIONAL 1-3 INCHES WILL BE POSSIBLE TODAY, WITH THE HIGHEST  
TOTALS ACROSS THE WESTERN HALF OF THE REGION.  
 
BY SATURDAY, THE REMNANTS OF IMELDA SHOULD BE WELL NORTH OF THE  
REGION, MERGING WITH A FRONTAL ZONE IN THE CENTRAL PLAINS AND  
MIDWEST. UPPER LEVEL RIDGING WILL BEGIN TO BUILD INTO THE SE CONUS  
AND INTO OUR REGION. DESPITE THE RIDGING, DECIDED TO MAINTAIN  
SLIGHT RAIN CHANCES ACROSS DEEP EAST TX AND WEST-CENTRAL LOUISIANA  
AS DEEP SOUTHERLY FLOW ALONG WITH DAYTIME HEATING COULD RESULT IN  
ISOLATED AFTERNOON CONVECTION. SOME OF THIS CONVECTION COULD MOVE  
FURTHER NORTH TOWARD THE I-20 CORRIDOR OF EAST TX AND NW LOUISIANA,  
BUT CONFIDENCE IS LOW AT THIS TIME.  
 
TEMPERATURES WILL REMAIN BELOW NORMAL TODAY WITH THE RAIN AND  
CLOUD COVER OVER THE REGION. AFTERNOON HIGHS WILL STRUGGLE TO  
REACH THE MID 80S. LOOK FOR AFTERNOON TEMPERATURES TO REBOUND INTO  
THE UPPER 80S TO NEAR 90 DEGREES ON SATURDAY WITH THE UPPER RIDGE  
EXPANDING INTO THE REGION. /20/  
 
LONG TERM.../SUNDAY THROUGH FRIDAY/  
 
BY THE END OF THE WEEKEND, UPPER RIDGING WILL BE SET UP ACROSS THE  
SOUTHEAST U.S. WITH THE RIDGE AXIS EXTENDING WESTWARD ACROSS THE  
LOWER MISS RIVER VALLEY INTO S TX. A LONGWAVE TROUGH SHOULD BE  
MOVING OUT OF THE INTERMOUNTAIN WEST SUN MORNING, FILLING AS IT  
EJECTS QUICKLY INTO THE CENTRAL AND NORTHERN PLAINS BY SUN EVENING.  
CANNOT RULE OUT SOME ISOLATED, DIURNALLY DRIVEN CONVECTION ACROSS  
OUR WESTERN HALF ON SUNDAY WHERE MOISTURE WILL BE A LITTLE MORE  
PREVALENT. THERE WILL BE WEAK FRONTAL BOUNDARY IN ASSOCIATION WITH  
THIS EJECTING LONGWAVE TROUGH THAT WILL TRY TO BACKDOOR INTO OUR  
NORTHERN THIRD MONDAY AFTN/EVNG WHICH COULD HELP TO FOCUS SCATTERED  
CONVECTION ALONG AND AHEAD OF IT SO DID BEEF POPS UP TO LOW END  
CHANCE VARIETY TO ACCOUNT FOR THIS. WHAT IS LEFT OF THIS BOUNDARY  
SHOULD RETURN BACK TO THE NORTH OR WASHOUT ALL TOGETHER TUE INTO WED.  
 
BY WED, THE UPPER RIDGE AXIS WILL BEGIN TO LOSE ITS IDENTITY ACROSS  
THE SOUTHERN PLAINS WITH SOUTHWEST FLOW ALOFT DEVELOPING ACROSS THE  
PLAINS AS AN UPPER LEVEL TROUGH CARVES ITS WAY ACROSS THE SOUTHWEST  
CONUS. KEPT POPS OUT OF THE FORECAST FOR WED BUT DID INCREASE POPS  
TO LOW END CHANCE VARIETY FOR THU AS THIS TROUGH EJECTS OUT INTO THE  
SOUTHERN PLAINS. THIS TROUGH SHOULD HELP TO TAP DEEPER GULF OF  
MEXICO MOISTURE ON THU WHICH SHOULD SUPPORT THE INCREASE IN  
CONVECTIONAL COVERAGE. WE ARE BACK TO ISOLATED DIURNALLY DRIVEN  
CONVECTION FOR FRI WITH SOUTHWEST FLOW ALOFT CONTINUING IN THE WAKE  
OF THE EJECTING TROUGH.  
 
13  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
SHV 83 70 88 71 / 60 10 10 10  
MLU 85 69 90 70 / 50 20 10 10  
DEQ 79 70 88 70 / 100 40 10 10  
TXK 80 69 88 71 / 70 30 10 10  
ELD 81 68 89 69 / 50 30 10 10  
TYR 86 71 88 71 / 50 10 10 10  
GGG 84 71 88 71 / 50 10 10 10  
LFK 85 71 87 71 / 50 10 20 10  
 

 
   
SHV WATCHES/WARNINGS/ADVISORIES
 
 
AR...NONE.  
LA...NONE.  
OK...NONE.  
TX...NONE.  

 
 

 
 
50/13/20  
 
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