168
FXUS64 KLCH 210433
AFDLCH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1133 PM CDT THU AUG 20 2026
..NEW DISCUSSION, AVIATION, MARINE, FIRE WEATHER
KEY MESSAGES
- AN EXTREME HEAT WARNING HAS BEEN ISSUED FOR CENTRAL LOUISIANA,
MOST OF SOUTHWEST LOUISIANA AND SOUTHEAST TEXAS FROM 10 AM TO 8
PM. THIS IS FOR HIGH TEMPERATURES 100 TO 105F AND/OR HEAT
INDICES 113 TO 115F.
- A HEAT ADVISORY WILL BE IN EFFECT FOR ALL OTHER AREAS FRIDAY
FROM 10 AM TO 8 PM FOR HEAT INDICES UP TO 112F AND HIGH TEMPS 99
TO 101F.
- HEAT STRESS LEVELS WILL INCREASE TO EXTREME (LEVEL 4 OF 4) FOR
SOUTHEAST TEXAS AND LOUISIANA FRIDAY TO MONDAY. MAJOR TO EXTREME
LEVELS WILL THEN CONTINUE INTO NEXT WEEK.
- A WEAK BOUNDARY WILL MOVE THROUGH LATE FRIDAY WITH SEVERE
WEATHER POSSIBLE. SPC HAS PLACED EASTERN PARTS OF THE CWA UNDER
A MARGINAL RISK.
- LIGHTNING AND GUSTY WINDS COULD EXACERBATE FIRE CONDITIONS. VEGETATION
WILL CONTINUE DRYING WITH THESE CONDITIONS. CHECK WITH YOUR
LOCAL OFFICIALS FOR BURN BANS ACROSS SETX AND CEN/SWLA.
DISCUSSION
(TONIGHT THROUGH NEXT THURSDAY)
ISSUED AT 1125 PM CDT THU AUG 20 2026
A SUBSTANTIAL 500 MB HEAT DOME IS CENTERED NEAR THE FOUR CORNERS
REGION IN THE DESERT SOUTHWEST WITH HEIGHTS AROUND 598 DM.
OVERHEAD 500 MB HEIGHTS ARE A LITTLE LOWER AROUND 594 DM, BUT
STILL NEAR THE 95TH PERCENTILE FOR HEIGHTS THIS TIME OF YEAR. AT
THE SURFACE, HIGH PRESSURE IN THE EASTERN GULF WILL CONTINUE TO
BRING LIGHT SOUTH WINDS TO THE AREA.
THERE ARE TWO MAIN CONCERNS FOR TOMORROW: HEAT AND SEVERE
WEATHER. LET’S START WITH THE MORE IMPACTFUL HEAT FORECAST.
AFTERNOON HIGHS WILL CONTINUE TO CLIMB, WITH TEMPERATURES WELL
INTO THE TRIPLE DIGITS FOR CENTRAL LOUISIANA AND THE INTERIOR
PORTIONS OF SOUTHEAST TEXAS. FOR THOSE LOCATIONS, AN EXCESSIVE
HEAT WARNING HAS BEEN ISSUED. FOR THE REST OF THE REGION,
TEMPERATURES WILL MAKE A DECENT RUN AT TRIPLE DIGITS EVEN DOWN TO
THE I-10 CORRIDOR, WITH DESI PROBABILITIES SHOWING AROUND A 40%
CHANCE THAT LAKE CHARLES WILL REACH 100°F ON FRIDAY. BECAUSE OF
THESE TEMPERATURES, A HEAT ADVISORY IS IN PLACE ACROSS THE COAST.
WHILE THE REST OF THE REGION HAS BEEN UPGRADED TO AN EXCESSIVE
HEAT WARNING. THE MAIN SAVING GRACE THE PAST SEVERAL DAYS HAS BEEN
THE MIXING OF LOWER DEW POINTS ALOFT DOWN TO THE SURFACE.
MOISTURE FROM THE REMNANTS OF AN MCS TO OUR NORTH WILL MOVE SOUTH
OVERNIGHT. FORECAST SOUNDINGS SHOW RH VALUES AT THE LOW LEVELS
INCREASING IN RESPONSE, WITH RH AT 850 MB RISING FROM 50% TO 70%
WHILE VALUES AT 700 MB INCREASE FROM 40% TO 60%. WITH THE LACK OF
DRY AIR MIXING DOWN, IT WILL FEEL LIKE A SAUNA ACROSS THE REGION,
AND HEAT INDEX VALUES WILL SOAR ABOVE 110°F AREA-WIDE. HEAT SAFETY
SHOULD BE A PRIORITY ON FRIDAY AND SATURDAY! MAKE SURE TO TAKE
BREAKS FROM THE HEAT AND STAY WELL-HYDRATED.
THE SECOND MAJOR CONCERN FOR TOMORROW IS THE POSSIBILITY OF
SEVERE WEATHER. A MESOSCALE CONVECTIVE SYSTEM (MCS) IS EXPECTED TO
MOVE SOUTH AS IT ENTERS OUR AREA. STRONG DAYTIME HEATING,
COMBINED WITH A MOIST AIR MASS, WILL CREATE AN ENVIRONMENT
FAVORABLE FOR STRONG TO SEVERE THUNDERSTORMS. HIGH-RESOLUTION
CONVECTIVE-ALLOWING MODEL (CAM) SOUNDINGS SHOW SURFACE-BASED CAPE
VALUES BETWEEN 2500 AND 3000 J/KG, WITH DCAPE VALUES AROUND 1200
J/KG. WHILE SHEAR VALUES ARE LIMITED—WITH 0–6 KM BULK SHEAR LESS
THAN 20 KNOTS—THIS SETUP SUPPORTS WATER-LOADED MICROBURST.
CONSEQUENTLY, THE SPC HAS PLACED OUR AREA UNDER A MARGINAL RISK
(LEVEL 1 OF 5), WITH DAMAGING STRAIGHT-LINE WINDS BEING THE
PRIMARY THREAT. CAMS INDICATE THIS LINE WILL REACH THE COAST;
GIVEN THE RECENT DRY CONDITIONS, ANY RAINFALL WILL BE BENEFICIAL.
FOR THE REST OF THE FORECAST, WE ARE LOOKING AT A MORE
TRANSITIONAL PATTERN. THE 500 MB RIDGE THAT HAS BEEN LOCKED
OVERHEAD WILL ERODE, ALLOWING A SERIES OF TROUGHS TO ROTATE AROUND
THE RIDGE, BRINGING MORE CHANCES FOR WIDESPREAD RAIN NEXT WEEK.
EVEN WITH THE INCREASE IN RAIN, TEMPERATURES WILL STILL REMAIN IN
THE MID TO UPPER 90S.
AVIATION
(06Z TAFS)
ISSUED AT 1125 PM CDT THU AUG 20 2026
OVERNIGHT CONDITIONS WILL BE VFR WITH LIGHT AND VARIABLE WINDS.
FOR MOST OF TOMORROW CONDITIONS WILL BE VFR BUT WITH HIGH OVERCAST
SKIES. CONVECTION WILL START TO MOVE THROUGH THE AREA LATE FRIDAY
AFTERNOON AND INTO THE EVENING. CAMS ARE IN DISAGREEMENT ON
EXTENT AND TIMING FOR THESE SHOWERS AND T-STORMS SO PROB30 IS USED
IN THE EXTENDED TAF FORECAST.
MARINE
ISSUED AT 1125 PM CDT THU AUG 20 2026
LIGHT TO MODERATE SOUTH-SOUTHWEST FLOW WILL CONTINUE FOR THE NEXT
SEVERAL DAYS. OVERNIGHT ON FRIDAY WE COULD SEE A FEW SHOWERS AND
THUNDERSTORMS ALONG THE COAST BUT PROBABILITIES REMAIN UNLIKELY,
AROUND 20%. WAVES WILL REMAIN BELOW 3 FEET THROUGH THE WEEKEND AND
INTO NEXT WEEK.
FIRE WEATHER
ISSUED AT 1125 PM CDT THU AUG 20 2026
A LARGE FIRE BROKE OUT CLOSE TO U.S. 171 NEAR LEESVILLE THAT
REQUIRED MULTIPLE FIRE DEPARTMENTS TO CONTAIN. LARGE FUELS ARE
SHOWING STRESS, WITH DEAD 10-HOUR FUELS AT ~12% FUEL MOISTURE (FM)
AND 1-HOUR FUELS BELOW 10% FM. THE FORECAST IS A BIT OF A MIXED
BAG, WITH THE LATEST CAMS SHOWING AN UPTICK IN RAIN CHANCES,
ESPECIALLY FOR CENTRAL LOUISIANA. THE EXTENT OF THE RAINFALL WILL
BE SPOTTY, BUT ENOUGH AREAS SHOULD GET A WETTING RAIN TO PUT A
DENT IN THE KBDI VALUES, WHICH CURRENTLY SIT BETWEEN 650 AND 700.
FOR MORE INFORMATION ON THE SEVERE THREAT, PLEASE SEE THE FORECAST
DISCUSSION. OVER THE WEEKEND, CONDITIONS WILL NOT IMPROVE MUCH AS
MINRH VALUES WILL BE IN THE MID-30S. THE ONLY REASON WE ARE
UNLIKELY TO ISSUE FIRE WEATHER PRODUCTS IS A LACK OF WINDS, WITH
SPEEDS FORECASTED TO BE LIGHT AND VARIABLE. STILL, MULTIPLE BURN
BANS ARE IN PLACE ACROSS THE REGION AND OUTDOOR BURNING SHOULD BE
DISCOURAGED.
LCH WATCHES/WARNINGS/ADVISORIES
LA...EXTREME HEAT WARNING FROM 10 AM TO 8 PM CDT FRIDAY FOR
LAZ027>033-044-045-055-141>143-152>154-241>243.
HEAT ADVISORY FROM 10 AM TO 8 PM CDT FRIDAY FOR LAZ073-074-
252>254.
TX...EXTREME HEAT WARNING FROM 10 AM TO 8 PM CDT FRIDAY FOR TXZ180-
201-259>262-515-516-615-616.
GM...NONE.
PUBLIC/FIRE/MARINE...14
AVIATION...14
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page