textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1212 PM CDT Fri Aug 28 2026

- Very hot, record to near record-breaking, temperatures are expected to persist.

- Widespread Major (Level 3 of 4) to Extreme (Level 4 of 4) Heat Risk is expected.

- There remains a low (25% or less) chance for sea breeze showers and thunderstorms, particularly along and east of IH-69C/US-281, each afternoon.

DISCUSSION

Issued at 1212 PM CDT Fri Aug 28 2026

The 500mb ridge of high pressure across the Desert SW elongates and shifts towards the Southern Plains through much of the forecast period, which will maintain mid-summer like heat and begin a more persistent influence of tropical moisture into Deep South Texas through next week. Weaker pressure along the Gulf coast may combine with the added moisture to initiate isolated sea breeze showers or thunderstorms during the afternoon hours this weekend through next week. Current POPs sit around 20 percent or less this weekend and below 15 percent for next week. Near daily surges of PWAT values to 2.1 inches, near the 90th percentile for late August and early September, are expected, however, model QPF remains bleak and very isolated, with no drought relief expected. The added humidity on top of above normal high temperatures will continue a Major (level 3 of 4) to Extreme (level 4 of 4) Heat Risk for heat-related illness each day, with little to no relief each night.

AVIATION

(18Z TAFS) Issued at 1212 PM CDT Fri Aug 28 2026

VFR conditions are expected to prevail through the TAF period with a southeast breeze this afternoon into early this evening.

MARINE

Issued at 1212 PM CDT Fri Aug 28 2026

Light to moderate southeasterly winds and low to moderate seas are expected to prevail across the coastal waters of Deep South Texas through the forecast period. A daily moderate chop is expected on the bay next week with Gulf seas of generally 1 to 3 feet. There is a low (less than 25 percent) chance of showers and thunderstorms.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 80 97 80 97 / 0 20 0 20 HARLINGEN 75 100 75 101 / 0 20 0 20 MCALLEN 80 103 80 103 / 0 10 0 10 RIO GRANDE CITY 78 103 78 103 / 10 10 10 0 SOUTH PADRE ISLAND 81 89 81 89 / 0 10 0 10 BAYVIEW/PORT ISABEL 78 95 78 96 / 0 10 0 20

BRO WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.