765  
FXUS64 KSHV 171732  
AFDSHV  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SHREVEPORT LA  
1232 PM CDT WED OCT 17 2018  
   
AVIATION
 
 
GRADUALLY IMPROVING FLIGHT CATEGORIES ARE EXPECTED TO CONTINUE  
THROUGH THIS AFTN AND INTO THE OVERNIGHT HOURS, AS CIGS SLOWLY  
LIFT. EXPECT SHWRS TO ALSO SLOWLY DIMINISH THROUGH THIS EVENING.  
OTHERWISE, NELY WINDS AROUND 10 KTS WILL CONTINUE THROUGH SUNSET,  
WITH SPEEDS DECREASING SOMEWHAT OVERNIGHT, AND INCREASING ONCE  
AGAIN TO AROUND 10 KTS AFTER SUNRISE THURSDAY. /12/  
 

 
   
PREV DISCUSSION
 
/ISSUED 1115 AM CDT WED OCT 17 2018/  
 
UPDATE.../TODAY/  
PERSISTENT AREA OF SHOWERS OVER THE ERN HALF OF THE CWA SHOWS NO  
SIGNS OF WEAKENING THROUGH THIS AFTN. LATEST RUN OF THE GFS AND  
THE 00Z RUN OF THE EURO SEEM TO BE HANDLING THE EVOLUTION OF THIS  
FEATURE REASONABLY WELL, AND BOTH SHOW THAT THIS RAIN WILL  
CONTINUE THROUGH THE REST OF THE DAYLIGHT HOURS AT LEAST. HAVE  
RAISED POPS ACROSS THESE AREAS FOR THE REST OF THE AFTN. HAVE ALSO  
MADE A FEW TWEAKS TO TEMPS FOR TODAY, BUT THESE ARE MINOR. UPDATED  
PRODUCTS OUT SHORTLY. /12/  
 

 
 
PREV DISCUSSION... /ISSUED 500 AM CDT WED OCT 17 2018/  
 
SHORT TERM.../TODAY THROUGH THURSDAY/  
AREAS OF -RA CONTINUES TO DEVELOP/SHIFT E GENERALLY BETWEEN THE  
I-30 AND I-20 CORRIDORS OF E TX, WHICH EXTENDS ACROSS MUCH OF N LA  
AS WELL THIS MORNING. THIS IS IN ASSOCIATION WITH WEAK  
CONVERGENCE ALONG AND N OF THE H850 TROUGH, AS WELL AS WEAK  
ELEVATED ISENTROPIC FORCING EMBEDDED IN THE SW FLOW ALOFT.  
HOWEVER, SFC OBS INDICATE THE LOW CIGS BEGINNING TO LIFT ACROSS SW  
AR THIS MORNING, AS DRYING BETWEEN THE BNDRY LYR AND H925  
CONTINUES TO SPILL SSW INTO PORTIONS OF EXTREME NE TX TO NEAR THE  
AR/LA BORDER. THIS TREND WILL CONTINUE TODAY WITH THE DRIER AIR  
BEGINNING TO DEEPEN LATE THIS MORNING THROUGH THE AFTERNOON ACROSS  
PORTIONS OF N LA AND ADJACENT SECTIONS OF NE TX. CONVERGENCE  
ALONG THE H850 TROUGH IS EXPECTED TO WEAKEN LATER THIS MORNING, AS  
DRIER AIR CONTINUES TO MIX SSW, WHICH SHOULD RESULT IN THE AREAS  
OF -RA DIMINISHING BY AFTERNOON. HOWEVER, GIVEN THE CURRENT RADAR  
TRENDS AND THE FACT THAT MEASURABLE RAIN IS STILL FALLING, HAVE  
INCREASED POPS THIS MORNING TO LIKELY ALONG THE I-20 CORRIDOR OF E  
TX/N LA, TAPERING POPS DOWN TO CHANCE N AND S OF THIS AREA. HAVE  
ALSO DROPPED MENTION OF POPS THIS MORNING FOR SE OK/NRN SECTIONS  
OF SW AR, ALTHOUGH THE SHORT TERM PROGS ARE IN GOOD AGREEMENT WITH  
AREAS OF SHRA CURRENTLY SW OF DFW BETWEEN MKN AND LZZ, LIFTING NE  
ALONG A WEAK INVERTED MID LEVEL TROUGH INTO PORTIONS OF NE TX/SE  
OK/ADJACENT SECTIONS OF SW AR. THESE SHRA WILL ENCOUNTER A DEEPER  
AREA OF DRIER AIR AS IT APPROACHES THE RED RIVER VALLEY, BUT STILL  
MAY RESULT IN SOME LIGHT QPF THIS AFTERNOON. THUS, HAVE RETAINED  
LOW CHANCE POPS THIS AFTERNOON FOR MUCH OF NE TX/SE OK/SW AR/NW  
LA, TAPERING TO SLIGHT CHANCE ELSEWHERE GIVEN THAT THE OVERALL  
FORCING MAY TAP INTO THE HIGH PW AIR MASS S OF I-20 THAT WILL  
LINGER THROUGH THE AFTERNOON. ANY SCT -SHRA SHOULD DIMINISH THIS  
EVENING AS THE RESPONSIBLE MID LEVEL ENERGY BEGINS TO WEAKEN. THE  
PROGS ALSO DEPICT WEAK DIRTY RIDGING ALOFT EXTENDING NW ACROSS  
MUCH OF THE AREA TODAY, AS THE WRN ATLANTIC/FL PENINSULA, AND GULF  
OF MX RIDGE BEGINS TO BRIDGE W. SHOULD SEE TEMPS CLIMB ABOUT 10  
DEGREES TODAY AS THE -RA GRADUALLY DIMINISHES AND CIGS BEGIN TO  
LIFT, AND HAVE KEPT READINGS CLOSER TO THE BLENDS/MAVMOS.  
 
THE WEDGE OF LOW LEVEL DRIER AIR IS EXPECTED TO CONTINUE  
BACKDOORING SW ACROSS N LA/LOWER E TX TONIGHT, ALTHOUGH THE H850  
CIGS SHOULD NOT SCATTER OUT MUCH FARTHER S THAN I-20 BY THURSDAY  
MORNING. HOWEVER, WEAK OVERRUNNING LOOKS TO COMMENCE BY THURSDAY  
MORNING, IN TIME AS A DEEPER WEDGE OF ELEVATED MOISTURE  
ORIGINATING FROM THE SW GULF BEGINS TO ADVECT N AROUND THE WRN  
PERIPHERY OF THE RIDGE. AS A RESULT, ISOLATED -SHRA MAY DEVELOP  
ACROSS THE SW SECTIONS OF E TX THURSDAY MORNING, WITH THE MOISTURE  
PROFILE BEGINNING TO DEEPEN ONCE AGAIN IN RESPONSE TO THIS  
MOISTURE ADVECTION/SATURATION FROM THE TOP DOWN FROM SHRA  
DEVELOPING/SPREADING N ACROSS CNTRL AND ECNTRL TX. HAVE INCREASED  
POPS TO LOW CHANCE FOR THE FAR WRN COUNTIES OF E TX THURSDAY  
AFTERNOON GIVEN THE GOOD AGREEMENT IN LIGHT QPF OVER THESE AREAS,  
WHILE ALSO MAINTAINING A BUFFER OF SLIGHT CHANCE POPS FOR SE  
OK/MUCH OF THE REMAINDER OF E TX. SHOULD SEE A CONTINUED TREND OF  
WARMING (BUT STILL BELOW NORMAL) DAYTIME TEMPS THURSDAY AS WELL,  
WITH LOW LEVEL MOISTURE ADVECTION EXPECTED TO INCREASE FROM THE S  
LATE THURSDAY NIGHT. THIS WILL OCCUR AS THE CLOSED LOW INDICATED  
ON THE MORNING WATER VAPOR IMAGERY OVER NRN AZ THIS MORNING, SHOULD  
BEGIN TO SLOWLY LIFT N INTO UT TONIGHT, BEFORE BECOMING ABSORBED  
INTO THE NW FLOW ALOFT BY THURSDAY NIGHT. THIS NEXT TROUGH WILL  
BEGIN TO AMPLIFY AHEAD OF THE NEXT SHORTWAVE TROUGHING DIGGING SE  
INTO THE NRN PLAINS FROM SASKATCHEWAN/MANITOBA. THUS, OVERRUNNING  
AND THE EVENTUAL INCREASE IN LARGE SCALE ASCENT WILL BEGIN TO  
INCREASE RESULTING IN AN INCREASE IN SHRA AS WE ROUND OUT THE END  
OF THE WORK WEEK.  
 
15  
 
LONG TERM.../THURSDAY NIGHT THROUGH TUESDAY NIGHT/  
THE VERY PERSISTANT UPPER LEVEL LOW OF LATE WILL BE LOCATED JUST  
TO THE NORTH OF THE FOUR CORNERS BY LATE THURSDAY AND IS VERY  
CLOSELY MODELED BY GFS/ECMWF TO OPEN WAVE AND SLIP INTO THE  
PATTERN MOVING OUT ACROSS THE PLAINS WHILE SLOWLY FILING THE LONG  
WAVE INTO A MORE ZONAL FLOW ACROSS THE COUNTRY BY THE START OF  
NEXT WEEK.  
 
HOWEVER, AS EXPECTED THIS WILL REFOCUS THE TROPICAL CONNECTION STILL  
LYING ACROSS TEXAS BACK INTO OUR AREA, INITIALLY ACROSS I-30 FOR LATE  
WEEK. THIS LARGE AREA OF RAIN SHOWERS WILL FILTER DOWN ACROSS I-20  
OVERNIGHT AND EVENTUALLY ALL OF THE CWA BY MID WEEKEND AS A NOW  
STRONGER COLD FRONT DROPS DOWN THE FRONT RANGE OF THE ROCKIES WITH A  
1032MB AIR MASS OVER IA BY SUNSET SATURDAY. THE RESULT WILL BE RAIN  
SHOWERS WILL AGAIN WORK ACROSS MOST OF THE AREA FRIDAY AND INTO  
SATURDAY WITH FRESH NORTHERLY WINDS THAT WILL DRIVE ALL THE MOISTURE  
SOUTHWARD DURING THE AFTERNOON.  
 
BY FAR, SUNDAY IS LOOKING TO BE THE MUCH BETTER DAY THIS WEEKEND  
WITH THE STILL 1028MB HIGH CENTERED OVER KT/TN ON AND ALL OF THE  
RICH MOISTURE BACK IN THE TROPICS FROM BROWNSVILLE TO MIAMI. THE  
WORK WEEK STARTS OUT DRY AND BELOW AVERAGE ON TEMPS AND NOW LOOKS TO  
CONTINUE AS SUCH INTO MIDWEEK BEFORE THE NEXT PACIFIC CYCLONE SPINS  
UP SOUTH OF BAJA AND LOOMS BEYOND THIS SCOPE. MEANWHILE, A WEAK  
UPPER LOW WILL SKIRT ALONG THE GULF COAST FROM MID TO LATE WEEK,  
KEEPING PRIMARILY JUST TO THE SOUTH OF OUR AREA. THIS IS A LITTLE  
DIFFERENT THAN RECENT DAYS AND PERHAPS A CHANCE FOR US TO DRY OUT.  
/24/  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
SHV 57 55 64 55 / 50 20 10 10  
MLU 60 54 68 55 / 40 10 10 10  
DEQ 64 52 62 52 / 20 20 10 30  
TXK 59 51 62 51 / 40 20 10 20  
ELD 59 51 64 52 / 40 20 10 10  
TYR 54 54 63 52 / 60 20 30 10  
GGG 55 55 63 54 / 60 20 20 10  
LFK 58 56 68 57 / 20 20 20 10  
 

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

 
 

 
 
12/15/24  
 
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