textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 615 AM CDT Sun Aug 2 2026

- A Heat Advisory is in effect for inland to coastal Kenedy, Willacy, and Cameron counties from 11 AM to 6 PM Sunday for Heat Indices between 110-113 degrees. - Hot, breezy conditions will continue through Tuesday with Heat Indices between 103-113 and a Major to Extreme risk of heat related illness.

- Low to medium (15 to 35%) chance of isolated showers and thunderstorms on Sunday, mainly west of US281.

DISCUSSION

Issued at 1100 PM CDT Sat Aug 1 2026

The persistent ridge of high pressure across the Desert SW remains generally parked through much of the week, pivoting slightly westward to the Pacific Coast. This will maintain above normal temperatures across Deep South Texas through the forecast period but also allow humidity to increase along the lower Texas coast with weaker pressure. There is a Major (level 3 of 4) to Extreme (level 4 of 4) Heat Risk every afternoon into at least Tuesday, with little to no relief each night.

A weak frontal boundary dips south Sunday afternoon, combining with the heat of the day and any convergence with the sea breeze to potentially kick up scattered showers and thunderstorms into early Sunday evening, especially along and west of US281/I69C. Into next week, expect a low, but gradually increasing, chance of showers or thunderstorms along the sea breeze, especially by Thursday into next weekend.

Special Weather Statements will likely be needed each afternoon, with periodic Heat Advisories, mainly along the coast during the sea breeze each afternoon, as the humidity increases. Will issue a Heat Advisory for inland to coastal Kenedy, Willacy, and Cameron counties from 11 AM to 6 PM and let the next shifts determine the best locations for Special Weather Statements.

AVIATION

(12Z TAFS) Issued at 615 AM CDT Sun Aug 2 2026

VFR is anticipated at the aerodromes through the next 24 hours. Light to moderate winds at night will become breezy with higher gusts during the daylight hours. Although limited cloud cover and rain-free skies are also expected, some model guidance suggests that convection may become an issue for tonight. As a result, a TEMPO has been included for MFE and is based on the HRRR model.

MARINE

Issued at 1100 PM CDT Sat Aug 1 2026

Light to moderate southerly and southeasterly winds continue generally favorable marine conditions along the lower Texas coast with seas of 3 feet or less.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 100 80 98 81 / 10 0 0 0 HARLINGEN 103 76 102 78 / 20 0 0 0 MCALLEN 106 80 104 81 / 20 10 0 0 RIO GRANDE CITY 103 78 103 79 / 30 20 0 0 SOUTH PADRE ISLAND 89 80 89 81 / 0 0 0 0 BAYVIEW/PORT ISABEL 98 78 97 79 / 10 0 0 0

BRO WATCHES/WARNINGS/ADVISORIES

TX...Heat Advisory from 11 AM this morning to 6 PM CDT this evening for TXZ251-254-255-351-354-355.

GM...None.