546  
FXUS64 KHGX 210521  
AFDHGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX  
1221 AM CDT FRI AUG 21 2026  
   
..NEW DISCUSSION, AVIATION, MARINE
 
 
   
KEY MESSAGES
 
 
- HEAT ADVISORY IN EFFECT THROUGH SATURDAY. COULD BE EXTENDED INTO  
SUNDAY.  
 
- ISOLATED THUNDERSTORMS ARE POSSIBLE LATER TODAY AND THIS  
EVENING, AND AGAIN SATURDAY AFTERNOON AND EVENING.  
 
- HOT WEATHER EXPECTED TO CONTINUE THROUGH NEXT WEEK.  
 

 
   
DISCUSSION
 
 
ISSUED AT 1202 AM CDT FRI AUG 21 2026  
 
IT'S HARD TO NOT SOUND LIKE A BROKEN RECORD WHEN WE'RE IN THE  
MIDDLE OF A VERY HOT AND GENERALLY DRY PATTERN. A STRONG RIDGE  
CENTERED OVER THE FOUR CORNERS REGION WILL BE THE DOMINANT PLAYER  
IN OUR FORECAST THROUGH MUCH OF THE NEXT WEEK. AFTERNOON  
TEMPERATURES ARE EXPECTED TO RANGE FROM THE LOW/MID 90S AT THE  
BEACHES TO 100-103F IN MOST INLAND LOCATIONS THROUGH AT LEAST  
TUESDAY, AND PERHAPS THROUGH THE END OF NEXT WEEK. OVER THE  
WEEKEND, I COULDN'T RULE OUT A FEW INLAND HOT SPOTS MAKING A RUN  
FOR THE 105 DEGREE MARK. MIXING SHOULD BRING DEW POINTS DOWN  
SOMEWHAT DURING THE AFTERNOON. BUT DEW POINTS ARE UNLIKELY TO FALL  
ENOUGH TO KEEP HEAT INDEX VALUES BELOW ADVISORY CRITERIA. IN  
FACT, SOME LOCATIONS IN OUR EASTERN COUNTIES COULD BE CLOSE TO  
EXCESSIVE HEAT WARNING THRESHOLDS (HEAT INDEX AT OR ABOVE 113),  
ESPECIALLY ON SATURDAY. FOR NOW, WE HAVE AN AREAWIDE HEAT ADVISORY  
THROUGH SATURDAY. THIS MAY NEED TO BE EXTENDED INTO SUNDAY. THE  
ONLY THING THAT COULD POTENTIALLY KNOCK THESE TEMPERATURES DOWN IS  
THE POTENTIAL FOR ISOLATED AFTERNOON / EVENING THUNDERSTORMS.  
 
WEAK DISTURBANCES EMBEDDED IN THE FLOW ALOFT, ALONG WITH  
CONVECTIVE OUTFLOW BOUNDARIES MAY SUFFICE TO INITIATE ISOLATED  
TO WIDELY SCATTERED CONVECTION LATE FRIDAY AFTERNOON AND EVENING,  
AND AGAIN SATURDAY AFTERNOON AND EVENING. CONFIDENCE IS QUITE LOW  
REGARDING WHETHER OR NOT THESE DISTURBANCES COUPLED WITH THE  
EXTREME HEAT AND MOISTURE WILL BE ENOUGH TO FOMENT CONVECTION. BUT  
IF THEY DO, THEN WE COULD NOT RULE OUT A LOCALLY STRONG  
THUNDERSTORM. ANY CONVECTIVE ACTIVITY IS EXPECTED TO APPROACH FROM  
THE NORTHEAST. THOSE WHO HAVE FOLLOWED SE TEXAS WEATHER KNOW THAT  
SOUTHWEST MOVING CONVECTION ON A HOT 100-DEGREE DAY CAN BE A SIGNAL  
FOR UNDERESTIMATED THUNDERSTORMS. SO A ROBUST MESOANALYSIS AND A  
WATCHFUL EYE ON THE RADAR WILL BE WARRANTED ON FRIDAY AND  
SATURDAY.  
 
SELF  
 

 
   
AVIATION
 
 
(06Z TAF ISSUANCE)  
ISSUED AT 1202 AM CDT FRI AUG 21 2026  
 
WINDS HAVE BEGUN TO DECREASED ACROSS THE AREA AS EVENING PROGRESSES.  
THE WILL CONTINUE TO LIGHT AND VRB THROUGH THE MORNING. A CHANCE FOR  
BRIEF BR CONTINUES FOR KLBX DURING THE SUNRISE HOURS. BEGINS TO  
PEAK OVER THE HORIZON AROUND KLBX DOES REMAIN POSSIBLE. TOMORROW A  
FRONTAL BOUNDARY WELL N OF THE AREA HAS THE CHANCE TO BRING THE  
DEVELOPMENT OF ISO TS/SH. CONFIDENCE REMAINS LOW, BUT WILL BE  
MONITORED. THE PERSISTENT FORECAST CONTINUES.  
 
CMW  
 

 
   
MARINE
 
 
ISSUED AT 1202 AM CDT FRI AUG 21 2026  
 
GENERALLY 10-15 KNOT SOUTHWEST WINDS AND 2-3 FOOT SEAS ARE  
EXPECTED THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. WINDS COULD  
GUST TO 20 KNOTS IN THE BAYS DURING THE AFTERNOON, AND OVER THE  
GULF DURING THE OVERNIGHT HOURS. ISOLATED THUNDERSTORMS ARE  
EXPECTED NORTH OF THE REGION FRIDAY AFTERNOON AND EVENING, AND  
AGAIN SATURDAY AFTERNOON AND EVENING. WE BELIEVE THESE STORMS WILL  
REMAIN NORTH, BUT THEY WILL BE WORTH WATCHING.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
COLLEGE STATION (CLL) 102 78 103 79 / 10 20 20 10  
HOUSTON (IAH) 102 81 102 81 / 10 20 20 10  
GALVESTON (GLS) 92 82 92 82 / 10 10 10 0  
 

 
   
HGX WATCHES/WARNINGS/ADVISORIES
 
 
TX...HEAT ADVISORY UNTIL 7 PM CDT SATURDAY FOR TXZ163-164-176>179-  
195>200-210>214-226-227-235>238-300-313-335>338-436>439.  
 
GM...NONE.  

 
 

 
 
DISCUSSION...SELF  
AVIATION...CMW  
MARINE...SELF  
 
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