820  
FXUS64 KBRO 221803  
AFDBRO  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BROWNSVILLE TX  
103 PM CDT FRI MAY 22 2026  
   
..NEW DISCUSSION, AVIATION, MARINE  
 
   
KEY MESSAGES  
 
UPDATED AT 1248 PM CDT FRI MAY 22 2026  
 
KEY MESSAGES:  
 
* ISOLATED SHOWERS AND THUNDERSTORMS COULD IMPACT THE WESTERN  
RANCHLANDS THIS EVENING AS CONVECTION FIRES OFF THE SIERRA  
MADRE.  
 
* A FLOOD WATCH IS IN EFFECT UNTIL MONDAY MORNING. THERE IS A  
CHANCE OF ISOLATED TO SCATTERED FLASH FLOODING IN AREAS THAT  
RECEIVE HEAVIER RAINFALL ON SATURDAY AND SUNDAY.  
 
* WARM AND HUMID CONDITIONS ARE EXPECTED THROUGH NEXT WEEKEND  
WITH MINOR (LEVEL 1 OF 4) AND MODERATE (LEVEL 2 OF 4) HEAT  
RISKS EXPECTED TO IMPACT THE AREA.  
 
* A MODERATE RISK OF RIP CURRENTS CONTINUES THROUGH SATURDAY AFTERNOON.  
 
 
   
DISCUSSION  
 
ISSUED AT 1248 PM CDT FRI MAY 22 2026  
 
A DEEPLY MOIST ATMOSPHERIC PROFILE REMAINS IN PLACE THROUGHOUT THE  
WEEKEND, DUE TO A COMBINATION OF AMPLE GULF SURFACE MOISTURE AND  
PACIFIC MOISTURE ALOFT, WHICH IS BEING CARRIED INTO DEEP SOUTH TEXAS  
ACROSS MEXICO DUE TO PERSISTENT WESTERLY 500 MB FLOW. RESULTANTLY,  
ABNORMALLY HIGH PWAT VALUES (BETWEEN 1.6 AND 2.2 INCHES) ARE  
EXPECTED OVER THE REGION, WITH THE HIGHEST VALUES BEING OBSERVED ON  
SATURDAY. SHORTWAVE ACTIVITY IS ALSO EXPECTED OVER THE NEXT FEW  
DAYS, WHICH WILL MAKE THE ATMOSPHERE UNSETTLED AND PRONE FOR  
CONVECTION TO FORM. SINCE THE ATMOSPHERIC PROFILE IS SO MOIST,  
CONVECTION THAT FORMS THIS WEEKEND WILL BE PERSISTENT AND EFFICIENT  
RAINMAKERS, WHICH COULD RESULT IN HIGH PRECIPITATION AMOUNTS AND  
POSSIBLY ISOLATED TO SCATTERED FLASH FLOODING ACROSS PORTIONS OF  
DEEP SOUTH TEXAS. A FLOOD WATCH IS IN EFFECT UNTIL MONDAY MORNING.  
 
THE REMAINDER OF THE AFTERNOON TODAY IS EXPECTED TO BE RELATIVELY  
DRY AND RAIN FREE, BUT CONVECTION IS EXPECTED TO FORM OFF THE SIERRA  
MADRES AFTER SUNSET WHICH COULD BRING A FEW SHOWERS AND  
THUNDERSTORMS TO THE WESTERN PORTION OF THE CWA DURING THE EVENING  
HOURS. OVERALL, POPS ARE EXPECTED TO REMAIN RELATIVELY LOW OVERNIGHT  
(LESS THEN 30 PERCENT), BEFORE INCREASING TO 50 TO 70 PERCENT  
TOMORROW, AS MORE WIDESPREAD CONVECTION IS EXPECTED TO FORM WITH THE  
MAIN SHORTWAVE DISTURBANCE. THE HIGHER POPS WILL SHIFT TO THE  
EASTERN COUNTIES ON SUNDAY AS THE MAIN DISTURBANCE MOVES SLIGHTLY TO  
THE EAST.  
 
THE WEATHER PREDICTION CENTER CURRENTLY HAS ALL OF DEEP SOUTH TEXAS  
IN A SLIGHT RISK (LEVEL 2 OF 4) FOR EXCESSIVE RAINFALL ON SATURDAY,  
AND THE COASTAL COUNTIES UNDER A MARGINAL RISK (LEVEL 1 OF 4) FOR  
SUNDAY. CURRENT PROBABILISTIC GUIDANCE FOR SATURDAY INDICATES A 15  
TO 25% RISK THAT RAINFALL COULD EXCEED FLASH FLOOD GUIDANCE. WHILE  
AREAS FURTHER NORTH (CLOSER TO CORPUS AND HOUSTON) ARE EXPECTED TO  
RECEIVE THE HEAVIEST RAINFALL, GIVEN THESE PROBABILITIES, IT IS  
THEREFORE POSSIBLE THAT SATURDAY'S EXCESSIVE RAINFALL RISK COULD  
TREND UPWARD IF GUIDANCE CAN AGREE BETTER ON WHERE THE AREAS OF  
HEAVIEST PRECIPITATION WILL OCCUR, OR IF THE HEAVIEST EXPECTED RAINFALL  
TRENDS MORE SOUTHWARD.  
 
MOST OF THE RAIN RECEIVED THIS WEEKEND IS EXPECTED TO BE BENEFICIAL.  
IT IS MOST LIKELY THAT THE MAJORITY OF AREAS WILL RECEIVE BETWEEN  
0.5-1.5 INCHES BETWEEN NOW AND MONDAY MORNING. HOWEVER, IT IS  
POSSIBLE THAT SOME LOCALIZED AREAS COULD RECEIVE UP TO 6 INCHES  
WHERE LOCALLY HEAVY RAINFALL OCCURS. AREAS THAT WILL BE PRONE TO  
ISOLATED FLASH FLOODING ARE PLACES WHERE AN EXCESS OF RAIN FALLS  
OVER A SHORT PERIOD OF TIME (2- 3 INCHES AN HOUR), OR IF TRAINING  
SHOWERS AND STORMS HAPPEN TO FORM, WITH SEVERAL SHOWERS GOING OVER  
A SINGLE AREA IN SUCCESSION. RIGHT NOW, THE HIGHEST PRECIP TOTALS  
AND THEREFORE HIGHEST CHANCES OF EXCESSIVE RAINFALL ARE EXPECTED  
OVER THE EASTERN PORTION OF THE NORTHERN RANCHLANDS. HOWEVER,  
ISOLATED TO SCATTERED FLASH FLOODING COULD STILL HAPPEN ANYWHERE  
IN DEEP SOUTH TEXAS AND IT WOULD BE DIFFICULT TO PINPOINT  
PRECISELY WHERE ISOLATED FLASH FLOODING WILL OCCUR, AS SHOWER  
DEVELOPMENT WILL BE SCATTERED AND RANDOM. THEREFORE, ALL FLOOD-  
PRONE AREAS SHOULD BE PREPARED FOR THE POSSIBILITY THIS WEEKEND,  
DESPITE MOST AREAS ONLY EXPECTED TO ACTUALLY RECEIVE BENEFICIAL  
RAIN.  
 
LOW RAIN CHANCES CONTINUE INTO MONDAY AS THE ATMOSPHERE REMAINS  
SOMEWHAT DISTURBED, WITH THE MAIN CHANCES (20-30%) IN THE WESTERN  
RANCHLANDS AS MORE SIERRA MADRE CONVECTION IS EXPECTED TO FORM.  
CONDITIONS DRY OUT TUESDAY, BUT MODERATE RAIN CHANCES (30-60%)  
RETURN FOR WEDNESDAY AND LINGER (20-30%) FOR THURSDAY BEFORE  
BECOMING DRY AGAIN FOR NEXT WEEKEND. TEMPERATURES WILL REMAIN WARM  
AND HUMID THROUGH THE NEXT WEEK, WITH MILD (LEVEL 1 OF 4) AND  
MODERATE (LEVEL 2 OF 4) HEAT RISKS THROUGHOUT THE WEEK.  
 
IN ADDITION, A MODERATE RISK OF LIFE-THREATENING RIP CURRENTS ARE  
EXPECTED TO IMPACT AREA BEACHES THROUGH AT LEAST SATURDAY  
AFTERNOON.  
 
 
   
AVIATION  
 
(18Z TAFS)  
ISSUED AT 1248 PM CDT FRI MAY 22 2026  
 
VFR CONDITIONS ARE EXPECTED AT ALL AIRPORTS WITH LIGHT TO MODERATE  
SOUTHEASTERLY WINDS. OVERCAST CONDITIONS ARE EXPECTED TO DEVELOP  
THIS EVENING, AND THERE IS A SMALL POSSIBILITY THAT MVFR CONDITIONS  
COULD BRIEFLY DEVELOP TONIGHT, BUT CONFIDENCE WAS NOT HIGH ENOUGH TO  
INCLUDE IT IN THE TAF PRODUCT.  
 
 
   
MARINE  
 
ISSUED AT 1248 PM CDT FRI MAY 22 2026  
 
FAVORABLE CONDITIONS ARE EXPECTED THIS WEEKEND INTO NEXT WEEK WITH  
LIGHT TO MODERATE SOUTHEASTERLY WINDS AND LOW (2 TO 4 FEET) WAVE  
HEIGHTS. CONDITIONS COULD BRIEFLY DETERIORATE IN THE IMMEDIATE  
VICINITY OF ANY SHOWERS AND THUNDERSTORMS THAT FORM OFFSHORE,  
PARTICULARLY OVER THE WEEKEND.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
BROWNSVILLE 79 91 77 90 / 10 50 60 70  
HARLINGEN 76 90 74 90 / 10 60 70 70  
MCALLEN 77 91 75 91 / 20 70 70 50  
RIO GRANDE CITY 75 90 73 91 / 30 50 60 30  
SOUTH PADRE ISLAND 80 85 79 84 / 20 40 60 60  
BAYVIEW/PORT ISABEL 78 89 76 89 / 10 50 60 70  
 
 
   
BRO WATCHES/WARNINGS/ADVISORIES  
 
TX...FLOOD WATCH THROUGH MONDAY MORNING FOR TXZ248>255-351-353>355-  
451-454-455.  
 
GM...NONE.  
 
 
 
 
SHORT TERM...55-MM  
LONG TERM....55-MM  
AVIATION...55-MM  
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