115  
FXUS64 KBRO 181823  
AFDBRO  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BROWNSVILLE TX  
123 PM CDT TUE AUG 18 2026  
   
..NEW DISCUSSION, AVIATION, MARINE  
 
   
KEY MESSAGES  
 
UPDATED AT 114 PM CDT TUE AUG 18 2026  
 
- HOT, DRY, AND AT TIMES BREEZY CONDITIONS WILL CONTINUE THROUGH  
THE WEEK AND INTO THE WEEKEND.  
 
- MODERATE (LEVEL 2 OF 4) TO MAJOR RISK (3 OF 4) OF HEAT-RELATED  
IMPACTS THROUGH THE WEEKEND WITH PEAK AFTERNOON HEAT INDICES  
GENERALLY BETWEEN 105 TO 112 DEGREES.  
 
- THERE IS INCREASED POTENTIAL FOR WILDFIRE SPREAD WEDNESDAY INTO  
THURSDAY DUE TO GUSTY CONDITIONS AND DRYING FUELS.  
 
 
   
DISCUSSION  
 
ISSUED AT 114 PM CDT TUE AUG 18 2026  
 
THE DOG DAYS OF SUMMER ARE HERE AS A LA CANICULA RIDGE TAKES HOLD  
ACROSS THE DESERT SOUTHWEST, NORTHERN MEXICO INTO THE WESTERN GULF  
STATES. THERE IS STRONG CONSENSUS AMONG THE GFS, ECMWF, AND CMC  
ENSEMBLE GUIDANCE WITH AN ANOMALOUSLY STRONG 594 DM RIDGE DRAPED  
OVER OUR REGION FOR THE NEXT TWO WEEKS. WHILE THE SUPER EL NINO HAS  
HELPED KEEP THE TROPICAL SYSTEMS AWAY FROM THE GULF COAST AND  
ATLANTIC BASIN, WE DO NEED THE RAIN AND UNFORTUNATELY, OUR DROUGHT  
SITUATION WILL LIKELY GET WORSE BEFORE ANY MEANINGFUL CHANCES FOR  
RELIEF. INDEED, THE 6-10 DAY CPC OUTLOOKS SHOW A 60-70 PERCENT  
PROBABILITY OF ABOVE NORMAL TEMPERATURES AND 40-50 PERCENT  
PROBABILITY OF BELOW NORMAL RAINFALL FOR DEEP SOUTH TEXAS. EVERY DAY  
IS PRETTY MUCH RINSE AND REPEAT UNTIL FURTHER NOTICE. THERE MIGHT BE  
AN ISOLATED SHOWER OR EVEN A THUNDERSTORM ALONG THE SEA BREEZE  
BOUNDARY EACH AFTERNOON, BUT THE OVERALL PATTERN TENDS TO SUPPRESS  
RAINFALL AND CONVECTION CHANCES.  
 
DAILY HIGH TEMPERATURES ARE EXPECTED TO RANGE FROM THE THE UPPER 90S  
TO AROUND 105 DEGREES, EXCEPT NEAR THE COAST. THE COMBINATION OF HOT  
TEMPERATURES AND ELEVATED DEWPOINTS IN THE 70S WILL SUPPORT HEAT  
INDICES GENERALLY BETWEEN 105 TO 110 DEGREES EACH AFTERNOON. HEAT  
INDICES MAY BRIEFLY REACH 111+ AT A FEW LOCATIONS IN THE AFTERNOON,  
ESPECIALLY THURSDAY AND FRIDAY. WIDESPREAD MODERATE (LEVEL 2 OF 4)  
TO MAJOR (LEVEL 3 OF 4) HEAT RISK EXPECTED THROUGH LATE WEEK INTO  
THE WEEKEND. WHETHER A SPECIAL WEATHER STATEMENT OR HEAT ADVISORY IS  
ISSUED FOR YOUR AREA, BE SURE TO EXERCISE CAUTION IF SPENDING TIME  
OUTDOORS AND ALWAYS LOOK BEFORE YOU LOCK.  
 
THE HOT, DRY, AND AT TIMES BREEZY CONDITIONS WILL SUPPORT THE  
POTENTIAL INCREASE OF FIRE WEATHER CONCERNS WEDNESDAY INTO THURSDAY.  
THE CURRENT D1 (MODERATE) TO D2 (SEVERE) DROUGHT COVERAGE LOOKS TO  
EXPAND FURTHER WITH THE UPCOMING U.S. DROUGHT MONITOR. WITH SUCH DRY  
ANTECEDENT CONDITIONS, EVAPOTRANSPIRATION RATES ARE EXTREMELY HIGH.  
THE DAILY EVAPOTRANSPIRATION RATES HAVE RANGED BETWEEN 0.4 AND 0.5  
INCHES PER DAY HERE AT WFO BROWNSVILLE. COMBINED WITH A 24-HOUR WIND  
RUN OF 100 TO 200 MILES EACH DAY, THIS REPRESENTS EXTREME, PEAK  
ATMOSPHERIC WATER DEMAND. IN OTHER WORDS, WE HAVE A RATHER DIRE  
SITUATION FROM A WATER RESOURCE MANAGEMENT AND AGRICULTURAL  
STANDPOINT WITH WORSENING DROUGHT AND ONGOING HOT CONDITIONS. WITH  
HOW RAPIDLY FUELS ARE DRYING OUT, IT IS NO SURPRISE THAT THE TEXAS  
A&M FOREST SERVICE IS NOW FORECASTING HIGH TO VERY HIGH FIRE DANGER  
FOR WEDNESDAY DUE TO A COMBINATION OF 15-20 MPH WINDS GUSTING 25+  
MPH AT TIMES AND DRY FUELS BASED ON 100HR AND ERC PERCENTILES.  
 
 
   
AVIATION  
 
(18Z TAFS)  
ISSUED AT 114 PM CDT TUE AUG 18 2026  
 
VFR WILL PREVAIL AT THE AERODROMES THROUGH THE NEXT 24 HOURS.  
BREEZY WINDS WITH HIGHER GUSTS UP TO 20 KT DURING THE DAY TIME WILL  
BE FOLLOWED BY LIGHTER WINDS FOR THE NIGHTTIME HOURS. DRY WEATHER  
WITH ONLY SCATTERED CLOUD COVER IS ALSO EXPECTED.  
 
 
   
MARINE  
 
ISSUED AT 114 PM CDT TUE AUG 18 2026  
 
GENERALLY FAVORABLE MARINE CONDITIONS WILL PREVAIL ALONG THE LOWER  
TEXAS COAST THROUGH THE PERIOD WITH LIGHT TO MODERATE WINDS AND LOW  
TO MODERATE SEAS. GENERALLY LOW TO MARGINALLY MODERATE RIP CURRENT  
RISK IS EXPECTED AS WAVE PERIOD INCREASE TO THE 5-6 SECONDS RANGE  
WITH A PERSISTENT SOUTHERLY TO SOUTH-SOUTHEASTERLY SWELL AND 2-3 FT  
WAVES. 15-20 KT WINDS OVER THE LAGUNA MADRE MID TO LATE WEEK COULD  
ALSO LEAD TO SMALL CRAFT EXERCISE CAUTION CONDITIONS. WITH SSTS IN  
THE LOW 80S AND WATERS LOOKING INVITING WITH THE ONGOING HOT  
WEATHER, PLEASE EXERCISE CAUTION AND BE AWARE OF RIP CURRENT RISK.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
BROWNSVILLE 80 97 82 98 / 0 0 0 0  
HARLINGEN 76 101 78 102 / 0 0 0 0  
MCALLEN 80 103 81 104 / 0 0 0 0  
RIO GRANDE CITY 77 103 79 104 / 0 0 0 0  
SOUTH PADRE ISLAND 81 90 82 90 / 0 0 0 0  
BAYVIEW/PORT ISABEL 79 97 80 97 / 0 0 0 0  
 
 
   
BRO WATCHES/WARNINGS/ADVISORIES  
 
TX...NONE.  
GM...NONE.  
 
 
 
 
SHORT TERM...88-CHAI  
LONG TERM....88-CHAI  
AVIATION...88-CHAI  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab TX Page
Main Text Page