textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1254 PM CDT Sat Sep 26 2026

- Hotter than normal temperatures will continue through Wednesday of next week.

- Widespread moderate (level 2 out of 4) to major (level 3 out of 4) heat risk with pockets of Extreme (Level 4 of 4) Heat Risk to continue across the region through Wednesday of next week.

- Rain chances increase for the later half of next week, as a cold front moves into Central Texas. Increased cloud cover could result in high temperatures remaining a few degrees cooler, likely still in the 90s.

DISCUSSION

Issued at 1254 PM CDT Sat Sep 26 2026

The pattern of hot temperatures with daily low chances for sea breeze convection is forecast to continue into early next week. By mid week, a pattern change is anticipated as tropical moisture from the remnants of Polo is absorbed into an upper level trough over the southwestern US. As the trough shifts further east through the later half of the week, it will likely support a cold front extending across Central Texas. While the front is forecast to stall across Central Texas, increased forcing and moisture ahead of the front could lead to increased clover and more widespread rain chances across Deep South Texas through the later half of the week.

Major to Extreme Heat Risk is likely to continue across portions of the Rio Grande Valley through early next week, however Heat Advisories likely wont be needed as peak heat indices are forecast to remain below 110 degrees. High temperatures may remain a few degrees cooler through the later half of the week due to increased cloud cover, though highs will likely remain in the 90s.

AVIATION

(18Z TAFS) Issued at 1254 PM CDT Sat Sep 26 2026

Generally VFR conditions are forecast to continue through the period. Increased cloud cover this afternoon along the sea breeze could result in VFR ceilings, with some isolated showers or thunderstorms possible. The latest model guidance keeps any convection that develops this afternoon west of BRO and HRL and south of MFE, though a shower or thunderstorm moving over one of the airfields cant be ruled out.

MARINE

Issued at 1254 PM CDT Sat Sep 26 2026

Generally favorable marine conditions are forecast to continue through early next week with light to moderate easterly to southeasterly winds and slight seas. Pressure gradients along the Lower Texas Coast are forecast to increase mid-week as a cold front moves into Central Texas. This will likely result in stronger winds and seas, leading to adverse or hazardous conditions on the Gulf waters and Laguna Madre.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 79 96 78 96 / 0 10 10 30 HARLINGEN 75 100 74 99 / 0 0 0 30 MCALLEN 78 102 78 102 / 0 0 0 10 RIO GRANDE CITY 77 103 77 102 / 0 0 0 0 SOUTH PADRE ISLAND 82 89 81 89 / 0 0 10 20 BAYVIEW/PORT ISABEL 77 94 77 94 / 0 10 10 30

BRO WATCHES/WARNINGS/ADVISORIES

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