815  
FXUS64 KSHV 181111  
AFDSHV  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SHREVEPORT LA  
511 AM CST FRI JAN 18 2019  
   
SHORT TERM
 
/TODAY THROUGH SATURDAY NIGHT/  
 
BIG CHANGES COMING TO THE REGION OVER THE NEXT 48 HOURS. FIRST  
THING FIRST, LIGHT AND VARIABLE WINDS THIS MORNING NEAR A SLOW  
MOVING COOL FRONT, ALONG WITH LOW LEVEL MOISTURE BENEATH A  
DIURNAL INVERSION HAS ALLOWED FOR LOW CLOUDS AND FOG ACROSS THE  
REGION. CLOSER TO THE FRONT, FOG HAS BECOME MORE DENSE. AS A  
RESULT, DECIDED TO ISSUE A DENSE FOG ADVISORY FOR PORTIONS OF  
DEEP EAST TEXAS, NORTHEAST LOUISIANA, AND CENTRAL LOUISIANA UNTIL  
10 AM THIS MORNING. THE FOG IS EXPECTED TO LIFT BY MID MORNING, AS  
SOUTHERLY WINDS PICK UP ACROSS THE REGION TO NEAR 10 MPH.  
UNSEASONABLY WARM TEMPERATURES EXPECTED TODAY AS HIGHS WILL CLIMB  
INTO THE UPPER 60S ACROSS THE REGION.  
 
AS WE MOVE INTO THE AFTERNOON HOURS TODAY, A LEE-SIDE TROUGH WILL  
BEGIN TO DEVELOP AND DEEPEN ACROSS SOUTHEASTERN COLORADO AND MOVE  
TOWARD THE PANHANDLE REGION OF TEXAS/OKLAHOMA. AT THE SAME TIME,  
MODELS SUGGEST SOME WEAK ISENTROPIC LIFT WILL DEVELOP THIS  
AFTERNOON AND SHOWERS WILL SPREAD OVER THE REGION. THE PRESSURE  
GRADIENT WILL ALSO STRENGTHEN AT THIS TIME AND WINDS WILL BEGIN  
TO BECOME MORE GUSTY FROM THE SOUTH/SOUTHWEST. A LAKE WIND  
ADVISORY MAY BE NEEDED DURING THIS PERIOD, BUT AT THIS TIME, WILL  
LEAVE THIS TO BE DECIDED DURING THE LATER FORECAST PACKAGE DUE TO  
TIMING ISSUES. THE TROUGH WILL CONTINUE TO PUSH TOWARDS THE  
REGION, DRAGGING A STRONG ARCTIC FRONT AND UPPER LOW WITH IT.  
ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BEGIN TO DEVELOP NEAR  
THE FRONTAL BOUNDARY. WITH STEEPENING MID-LEVEL LAPSE RATES AND  
COOL AIR ALOFT, A HAIL AND WIND THREAT WILL BE POSSIBLE ACROSS  
MOST OF THE REGION DURING THE LATE EVENING AND OVERNIGHT PERIOD.  
CAN'T RULE OUT THE POSSIBILITY FOR AN ISOLATED TORNADO AS WELL AS  
EFFECTIVE BULK SHEAR OF 40-50 KTS COULD SUPPORT SOME MID-LEVEL  
ROTATION.  
 
THE FRONT SHOULD SWEEP THROUGH THE REGION BY NOON TIME ON  
SATURDAY AND ARCTIC AIR WILL SPILL INTO THE REGION ALONG WITH  
GUSTY NORTHWEST WINDS NEAR 20 MPH WITH GUSTS NEAR 30 MPH. THERE  
IS THE SLIGHT CHANCE OF A RAIN/SNOW MIX NORTH OF A LINE FROM  
BROKEN BOW OKLAHOMA TO DIERKS ARKANSAS ON SATURDAY MORNING FROM  
WRAP AROUND MOISTURE FROM THE ASSOCIATED UPPER LOW AS IT MOVES  
ACROSS CENTRAL OKLAHOMA AND CENTRAL ARKANSAS. ALL ACTIVITY WILL  
MOVE OUT OF THE REGION BY SATURDAY AFTERNOON AND MUCH COOLER  
TEMPERATURES WILL SETTLE ACROSS THE REGION. TEMPERATURES WILL FALL  
INTO THE MID TO UPPER 20S AREAWIDE BY SUNDAY MORNING.  
 
/20/  
 
   
LONG TERM
 
/SUNDAY THROUGH FRIDAY/  
 
COLD POST FRONTAL TEMPERATURES IN THE WAKE OF THE UPPER TROUGH AXIS  
WHICH WILL BE WELL EAST OF THE REGION BY SUNDAY. THE GOOD NEWS IS  
THE WINDS SHOULD NOT BE AS STRONG ON SUNDAY AND WITH FULL SUN, WE  
SHOULD SEE TEMPERATURES WARMING UP INTO THE MIDDLE 40S TO LOWER 50S  
FOR DAYTIME HIGHS ON SUNDAY.  
 
WEAK UPPER LEVEL RIDGING SETS UP ACROSS OUR REGION FOR MONDAY BUT  
LOOKING OUT WEST, ANOTHER UPPER LEVEL TROUGH BEGINS TO DIG ACROSS  
THE FOUR CORNERS REGION OF THE COUNTRY. THIS WILL SET UP SFC  
CYCLOGENESIS IN THE LEE OF THE ROCKIES FOR MONDAY WITH A  
STRENGTHENING PRESSURE GRADIENT SETTING UP ACROSS THE SOUTHERN  
PLAINS. THE END RESULT WILL BE MUCH WARMER TEMPERATURES ON MONDAY  
WITH 60S RETURNING FOR MUCH OF THE REGION. THE UPPER TROUGH BEGINS  
TO ENTER THE PLAINS ON TUESDAY ALONG WITH AN ASSOCIATED COLD FRONT.  
LOOK FOR SHOWERS AND ISOLATED THUNDERSTORMS TO ACCOMPANY THIS  
FEATURE TUESDAY BEFORE EXITING THE REGION TUESDAY NIGHT. LATEST 00Z  
MEDIUM RANGE PROGS HINTING AT A SLOWER TROUGH PASSAGE TUESDAY  
NIGHT/WED TIME PERIOD SO WILL NEED TO WATCH THIS BUT CHOSE TO LEAVE  
WEDNESDAY DRY FOR NOW. THIS TROUGH WILL USHER IN ANOTHER SHOT OF  
COLD AIR TO CONCLUDE THE UPCOMING WORK WEEK.  
 
13  
 

 
   
PREV DISCUSSION
 
/ISSUED 1153 PM CST THU JAN 17 2019/  
 
AVIATION...  
 
FOR THE 18/06Z TAF PERIOD, A RANGE OF FLIGHT CONDITIONS STARTING  
OUT THIS PERIOD WITH A GENERAL TREND OF DETERIORATING CIGS/VSBYS  
OVERNIGHT AS A WEAK FRONTAL BOUNDARY WILL STALL ACROSS THE AREA.  
MVFR/IFR CONDITIONS WILL BE COMMON ACROSS ALL SITES THROUGH THE  
MORNING HOURS ON FRIDAY WITH SOME INTERMITTENT LIFR CONDITIONS  
POSSIBLE AROUND DAYBREAK. LOW CIGS AND FOG WILL LINGER THROUGH MID  
TO LATE MORNING BEFORE SLOW IMPROVEMENT IS EXPECTED AS S/SE WINDS  
INCREASE DUE THE FRONT LIFTING BACK NORTH FROM THE I-20 CORRIDOR.  
WIND SPEEDS WILL RANGE FROM 10-15 KTS WITH HIGHER GUSTS ON FRIDAY.  
OTHERWISE, MVFR/LOW VFR CIGS ARE LIKELY THROUGH FRIDAY AFTERNOON  
AS GULF MOISTURE CONTINUES TO INCREASE AHEAD OF A MUCH STRONGER  
COLD FRONT DUE TO ARRIVE EARLY SATURDAY. CONVECTION SHOULD BEGIN  
TO DEVELOP BY AROUND 19/00Z AS PRE-FRONTAL SHOWERS AND ISOLATED  
THUNDERSTORMS INCREASE WITH THE FRONT NOT EXPECTED TO MOVE IN  
UNTIL JUST AFTER THIS PERIOD CONCLUDES.  
 
/19/  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
SHV 67 47 51 28 / 20 70 20 0  
MLU 67 56 57 29 / 20 80 30 0  
DEQ 62 38 40 23 / 20 60 20 0  
TXK 62 41 44 25 / 20 60 20 0  
ELD 66 50 53 27 / 20 80 30 0  
TYR 67 40 42 27 / 20 60 20 0  
GGG 67 43 46 26 / 20 60 20 0  
LFK 69 47 50 27 / 20 60 20 0  
 

 
   
SHV WATCHES/WARNINGS/ADVISORIES
 
 
AR...NONE.  
LA...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR LAZ005-006-  
010>014-017>022.  
 
OK...NONE.  
TX...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR TXZ153-166-  
167.  
 

 
 

 
 
20/13  
 
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