426  
FXUS64 KBRO 232351 AAA  
AFDBRO  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE BROWNSVILLE TX  
651 PM CDT SAT MAY 23 2026  
   
..NEW AVIATION  
 
   
KEY MESSAGES  
 
UPDATED AT 628 PM CDT SAT MAY 23 2026  
 
KEY MESSAGES:  
 
- 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 THROUGH SUNDAY.  
 
- THE STORM PREDICTION CENTER AS ALL OF DEEP SOUTH TEXAS UNDER A  
MARGINAL RISK (LEVEL 1 OF 5) FOR SEVERE WEATHER THROUGH SUNDAY  
MORNING.  
 
- A MODERATE RISK OF RIP CURRENTS CONTINUES THROUGH SUNDAY  
EVENING.  
 
 
   
DISCUSSION  
 
ISSUED AT 227 PM CDT SAT MAY 23 2026  
 
AN UNSETTLED AND ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE  
THROUGH THE MIDDLE OF NEXT WEEK ACROSS DEEP SOUTH TEXAS AS  
EMBEDDED DISTURBANCES CONTINUE TO TRAVERSE THE WESTERLY TO  
NORTHWESTERLY FLOW ALOFT. THERE IS A POTENTIAL FOR STRONG TO  
SEVERE THUNDERSTORMS AND LOCALLY HEAVY RAINFALL, BUT THE EXACT  
TIMING OF ANY CONVECTION AND RAINFALL AMOUNTS REMAIN UNCERTAIN.  
 
THIS AFTERNOON/EVENING AND TONIGHT: DEEP SOUTH TEXAS WILL REMAIN  
UNDER THE INFLUENCE OF AN UPPER LEVEL SHORTWAVE TRAVERSING THE  
STATE, PROVIDING AMPLE FORCING FOR ASCENT. ADDITIONALLY, FORECAST  
MODEL SOUNDINGS AND THE 12Z BRO SOUNDING INDICATE A DEEP MOISTURE  
PROFILE, WITH PWATS UPWARDS OF 1.9 INCHES. DESPITE THIS MORNING’S  
CONVECTION STABILIZING THE ATMOSPHERE EARLY THIS AFTERNOON, THERE  
SHOULD BE SOME DESTABILIZATION ONCE AGAIN LATER THIS AFTERNOON,  
ESPECIALLY OVER NORTHERN MEXICO AND OUR FAR WESTERN COUNTIES. IN  
COMBINATION WITH FORCING FOR ASCENT, CONVECTION MAY DEVELOP LATE  
THIS AFTERNOON AND EVENING. HIGH RESOLUTION GUIDANCE HAS NOT BEEN  
HANDLING THIS SETUP THE BEST, BUT GIVEN THE CURRENT ENVIRONMENT -  
MLCAPE VALUES AROUND 2000-3000 J/KG, 0-6KM WIND SHEAR AROUND  
35-40 KNOTS, MID LEVEL LAPSE RATES AROUND 6-7 C/KM, AND PWATS  
UPWARDS OF 1.9-2 INCHES - MAY SUPPORT ADDITIONAL SHOWER AND  
THUNDERSTORM DEVELOPMENT AND ATTEMPT TO MAKE THEIR WAY TOWARDS THE  
GULF. THE MAIN THREAT WITH ANY SEVERE THUNDERSTORMS THAT DEVELOP  
WILL BE CAPABLE OF DAMAGING WIND GUSTS. ADDITIONALLY, THE  
ENVIRONMENT IS FAVORABLE FOR EFFICIENT RAIN-PRODUCING SHOWERS AND  
THUNDERSTORMS, WITH RAIN RATES OF 2-2.5”/HR. THIS MAY RESULT IN  
LOCALIZED FLASH FLOODING ISSUES, ESPECIALLY ACROSS PORTIONS OF THE  
REGION THAT RECEIVED HEAVY RAINFALL THIS MORNING. A FLOOD WATCH  
REMAINS IN EFFECT THROUGH MONDAY MORNING.  
 
THE BEST FORCING FOR ASCENT WILL SHIFT TO THE NORTH AND NORTHEAST  
AS THE SHORTWAVE TRANSLATES TOWARDS THE SOUTHERN PLANS BY SUNDAY,  
BUT ISOLATED SHOWERS AND THUNDERSTORMS MAY DEVELOP ESPECIALLY  
DURING THE LATE MORNING TO LATE AFTERNOON HOURS AS DIURNAL  
INSTABILITY INCREASES. RAIN CHANCES RANGE FROM AROUND 20-50%, WITH  
THE BEST CHANCES ALONG AND EAST OF US-281. THE REST OF THE WEEK,  
INCLUDING MEMORIAL DAY, REMAIN UNSETTLED WITH LOW TO MEDIUM  
CHANCES FOR SHOWERS AND THUNDERSTORMS. THERE IS STILL UNCERTAINTY  
AMONG GUIDANCE ON THE TIMING OF EMBEDDED DISTURBANCES AND AN  
APPROACHING UPPER LEVEL TROUGH FROM THE WESTERN US. HOWEVER, THE  
ENVIRONMENT WILL BE FAVORABLE FOR STRONG TO SEVERE THUNDERSTORMS  
AND LOCALLY HEAVY RAINFALL.  
 
 
   
AVIATION  
 
(00Z TAFS)  
ISSUED AT 628 PM CDT SAT MAY 23 2026  
 
VFR CONDITIONS ARE FORECAST TO CONTINUE THIS EVENING WITH MVFR  
CEILINGS DEVELOPING AT BRO AND HRL OVERNIGHT. THERE IS A LOW  
POTENTIAL FOR ANOTHER ROUND OF CONVECTION LATE THIS EVENING OR  
EARLY SUNDAY MORNING, THOUGH PROBABILITIES ARE TOO LOW FOR  
INCLUSION IN THE TAFS. VFR CONDITIONS ARE FORECAST TO RETURN AFTER  
SUNRISE, THOUGH A LOW PROBABILITY FOR SHOWERS AND THUNDERSTORMS  
WILL LINGER THROUGH THE REMAINDER OF THE PERIOD.  
 
 
   
MARINE  
 
ISSUED AT 227 PM CDT SAT MAY 23 2026  
 
GENERALLY FAVORABLE WINDS AND SEAS ARE EXPECTED TO PERSIST THROUGH  
THE FORECAST PERIOD. HOWEVER, NEAR DAILY CHANCES FOR SHOWERS AND  
THUNDERSTORMS WILL CONTINUE INTO THE MIDDLE OF NEXT WEEK. SATURDAY  
AND SUNDAY WILL LIKELY FEATURE THE HIGHEST RAIN/STORM CHANCES,  
AROUND 40-70%. THESE STORMS MAY PRODUCE HEAVY RAINFALL, FREQUENT  
LIGHTNING, STRONG WINDS, AND LOCALLY HIGHER SEAS.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
BROWNSVILLE 77 90 75 89 / 40 50 20 30  
HARLINGEN 73 89 71 88 / 30 40 10 30  
MCALLEN 75 90 74 90 / 30 30 20 30  
RIO GRANDE CITY 72 90 72 90 / 20 20 30 20  
SOUTH PADRE ISLAND 79 84 78 83 / 40 40 20 20  
BAYVIEW/PORT ISABEL 76 88 75 87 / 30 40 20 20  
 
 
   
BRO WATCHES/WARNINGS/ADVISORIES  
 
TX...FLOOD WATCH THROUGH MONDAY MORNING FOR TXZ248>255-351-353>355-  
451-454-455.  
 
GM...NONE.  
 
 
 
 
SHORT TERM...22  
LONG TERM....22  
AVIATION...60-BE  
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