076  
FXUS64 KSHV 220440  
AFDSHV  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SHREVEPORT LA  
1140 PM CDT THU JUN 21 2018  
   
AVIATION
 
 
VFR CONDITIONS WILL PREVAIL EARLY TONIGHT, BUT MVFR TO POSSIBLY  
IFR CIGS MAY DEVELOP AT THE MAJORITY OF THE TERMINALS OVERNIGHT,  
WITH THE POTENTIAL FOR MVFR VIS DUE TO FOG PARTICULARLY AT THE  
WESTERN TERMINALS. ANY LINGERING LOW CLOUDS AND FOG WILL SCOUR OUT  
BY MID-LATE MORNING TOMORROW, AND SCT-BKN VFR CIGS WILL PREVAIL  
BY TOMORROW AFTERNOON. COMPUTER MODELS HINT AT SOUTH- SOUTHWEST  
WIND SPEEDS INCREASING TO AROUND 10 KTS SUSTAINED WITH GUSTS OF  
15-20 KTS TOMORROW AFTERNOON AT THE MAJORITY OF THE TERMINALS.  
FURTHERMORE, THERE IS A CHANCE FOR -SHRA/-TSRA NEAR SUNRISE  
TOMORROW MORNING AND AFTERNOON, AT KTXK AND KELD, AND THUS A  
PREVAILING -SHRA VCTS HAS BEEN INSERTED, WITH A VCTS INSERTED AT  
KMLU. WILL OF COURSE AMEND AS NECESSARY.  
 

 
   
PREV DISCUSSION
 
/ISSUED 914 PM CDT THU JUN 21 2018/  
 
UPDATE...  
A FEW CHANGES WERE MADE TO THE ONGOING FORECAST. MAINTAINED THE  
SLIGHT CHANCE OF SHOWERS WITH ISOLATED THUNDERSTORMS ACROSS  
PORTIONS OF SOUTHWEST AR AND NORTHEAST TX THIS EVENING INTO  
TONIGHT, IN ASSOCIATION TO AN IMPENDING COLD FRONT. HOWEVER, ALSO  
INSERTED SLIGHT CHANCE POPS ACROSS PORTIONS OF DEEP EAST TX, AS A  
FEW ISOLATED SHOWERS HAVE POPPED UP JUST SOUTHWEST OF THE SAID  
AREA, LIKELY DUE TO AN OLD LINGERING SFC BOUNDARY. IN ADDITION,  
DROPPED THE OVERNIGHT TEMPERATURES BY A FEW DEGREES, WITH THE  
LOWEST TEMPERATURES (LOWER 70S) EXPECTED ACROSS PORTIONS OF  
SOUTHEAST OK AND SOUTHWEST AR DUE TO THE LINGERING COLD FRONT,  
VERSUS MIDDLE 70S ELSEWHERE. SUBSEQUENTLY, TWEAKED THE DEWPOINT  
TEMPERATURES AND RELATIVE HUMIDITY VALUES.  
 
PREV DISCUSSION... /ISSUED 624 PM CDT THU JUN 21 2018/  
 
AVIATION...  
VFR CONDITIONS WILL PREVAIL THIS EVENING, AS FEW-BKN VFR CIGS  
BECOME FEW-SKC SHORTLY AFTER SUNSET. MVFR-IFR CIGS WILL MAKE A  
RETURN OVERNIGHT AND HAVE TRIED TO INSERT BEST TIMING AT EACH  
TERMINAL. IN ADDITION, COULD SEE MVFR FOG AFFECT KTYR AND KGGG.  
ANY LINGERING LOW CLOUDS AND FOG WILL SCOUR OUT BY MID-LATE  
MORNING TOMORROW, AND SCT-BKN VFR CIGS WILL DOMINATE THE AIRSPACE  
BY TOMORROW AFTERNOON. COMPUTER MODELS HINT AT SOUTH-SOUTHWEST  
WIND SPEEDS INCREASING TO AROUND 10 KTS SUSTAINED WITH GUSTS OF  
15-20 KTS TOMORROW AFTERNOON AT THE MAJORITY OF THE TERMINALS.  
FURTHERMORE, THERE IS A CHANCE FOR -SHRA/-TSRA TOMORROW MORNING  
AND AFTERNOON,AT KTXK AND KELD, AND THUS A PREVAILING -SHRA VCTS  
HAS BEEN INSERTED, WITH A VCTS INSERTED AT KMLU. WILL OF COURSE  
AMEND AS NECESSARY.  
 
PREV DISCUSSION... /ISSUED 314 PM CDT THU JUN 21 2018/  
 
SHORT TERM.../TONIGHT THROUGH FRIDAY NIGHT/  
 
NWLY FLOW ALOFT PINNED BETWEEN THE RIDGE OVER THE DESERT SW AND A  
CLOSED UPPER LOW OVER THE MID MS RIVER VALLEY REGION WILL CONTINUE  
TO SEND IMPULSES SEWD ACROSS OUR REGION THROUGHOUT THE SHORT-TERM  
PD. WEAK SFC BOUNDARY ASSOCIATED WITH THE UPPER LOW TO BEGIN  
MIGRATING BACK NWD ACROSS OUR REGION OVERNIGHT, BECOMING PARALLEL  
TO THE UPPER FLOW SOMEWHERE ACROSS THE NRN THIRD OF OUR CWA. SHWRS/TSTMS  
WILL LIKELY DEVELOP DURING THE PRE- DAWN HOURS OVER THESE AREAS,  
AS THE FIRST OF SEVERAL IMPULSES INTERACTS WITH THE FRONT. HOWEVER,  
FRIDAY AFTN/EVENING, A SECONDARY IMPULSE WILL MOVE ACROSS THE  
REGION, AND, WITH AMPLE DAYTIME HEATING, MAY PRODUCE A FEW SEVERE  
STORMS CAPABLE OF MAINLY DAMAGING WINDS, LARGE HAIL, AND ISOLD  
TORNADOES.  
 
AS FOR TEMPS IN THE SHORT-TERM, OVERNIGHT LOWS IN THE MID 70S  
SEEMS REASONABLE, AS CLOUD COVER IS LIKELY TO AFFECT AT LEAST SOME  
PORTIONS OF THE REGION. SHORT-TERM BLENDS INDICATE A MUCH WARMER  
DAY FOR FRIDAY THAN WE'VE SEEN IN THE LAST SEVERAL DAYS. HAVE  
MODIFIED THIS DOWNWARD SOMEWHAT, AS CLOUD COVER/CONVECTION IS  
LIKELY TO INHIBIT HEATING AT LEAST A LITTLE, BUT STILL EXPECTING  
LOW TO MID 90S JUST ABOUT EVERYWHERE. HIGHER HUMIDITIES WILL ALSO  
RESULT IN HEAT INDEX READINGS BETWEEN 100 AND 104 FOR MUCH OF THE  
REGION. /12/  
 
LONG TERM.../SATURDAY THROUGH THURSDAY/  
 
AN MCS SHOULD BE ONGOING ACROSS ERN OK/AR SATURDAY MORNING, ALONG  
THE PRIMARY UPPER LEVEL SHORTWAVE IMPULSE THAT E INTO THE MID-SOUTH.  
OUTFLOW BNDRYS MAY PROPAGATE ESE ACROSS EXTREME SE OK AND THE NRN  
PORTIONS OF SW AR, BUT SHOULD ENCOUNTER AN INCREASINGLY DRIER LOW  
LEVEL AIR MASS FARTHER S INTO NE TX/N LA SUCH THAT HAVE MAINTAINED  
SLIGHT CHANCE POPS SATURDAY ACROSS THE FAR NRN ZONES. ANOTHER IN A  
SERIES OF UPPER LEVEL IMPULSES WILL AGAIN TRAVERSE THE RED RIVER  
VALLEY OF SRN OK AND SHIFT E INTO AR SATURDAY NIGHT/SUNDAY, WHICH  
MAY BUILD A LITTLE FARTHER SSE INTO EXTREME NE TX/SRN AR, AND THUS  
HAVE MAINTAINED LOW CHANCE POPS N OF THE I-30 CORRIDOR, AND SLIGHT  
CHANCE POPS S TO JUST N OF I-20 IN E TX AND ACROSS MUCH OF SW AR.  
BUT AGAIN, DEEP LYR DRIER AIR SHOULD RESTRICT THE SWD DEVELOPMENT OF  
ANY CONVECTION, BEFORE THESE IMPULSES SHIFT E OF THE MS VALLEY LATE  
IN THE DAY.  
 
AFTERWARDS, UPPER LEVEL RIDGING WILL AMPLIFY N ACROSS THE LOWER MS  
VALLEY AND SE CONUS MONDAY AND LINGER THROUGH MUCH OF THE NEW WORK  
WEEK, RESULTING IN VERY HOT AND DRY CONDITIONS AREAWIDE THROUGH THE  
PERIOD. TEMPS SHOULD TOP OUT IN THE MID 90S AREAWIDE, BUT COULD  
CLIMB FURTHER AS DRYING FROM THE RECENT RAINS CONTINUE AND ERODE  
TOPSOIL MOISTURE. COULD SEE A RETURN OF ISOLATED CONVECTION ACROSS  
THE SRN ZONES BY THE END OF THE WEEK, WHICH COULD BE MORE SEABREEZE  
INDUCED (WITH THE ERN MOST POSITION OF THE RIDGE PER THE GFS), OR  
VIA A WEAKNESS AROUND THE ERN PERIPHERY OF THE RIDGE SHOULD IT BE  
CENTERED FARTHER W OVER THE OZARKS/SRN PLAINS (PER THE ECMWF). /15/  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
SHV 76 96 76 94 / 10 20 10 10  
MLU 75 93 75 93 / 20 30 20 10  
DEQ 70 93 74 93 / 20 40 30 20  
TXK 74 93 76 93 / 20 40 20 10  
ELD 75 92 74 93 / 20 40 30 10  
TYR 76 96 76 94 / 10 20 10 10  
GGG 76 95 76 94 / 10 20 10 10  
LFK 75 95 76 95 / 20 20 10 10  
 

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

 
 

 
 
29/12/15  
 
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