textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1049 PM CDT Wed Oct 21 2026

- Low to medium (20-50%) chances of rain today across the region, with highest chances along the coast and in the mid- upper RGV.

- Outside of isolated showers possible Saturday, skies should remain mostly dry through the weekend. Low to medium chances of rain return early next week.

- Near average temperatures and patchy to widespread minor risks of heat-related illnesses (level 1/4) continue.

- A medium risk of rip currents continues through tomorrow afternoon.

DISCUSSION

Issued at 1049 PM CDT Wed Oct 21 2026

Elevated rain chances continue today as deep moisture interacts with an upper level disturbance. Scattered showers over the Gulf waters will continue to move west-southwest, bringing welcome rain to the coast and NE Ranchlands through this morning. As moisture encroaches westward, isolated to scattered showers and thunderstorms will move southwest through Thursday afternoon. Shower coverage should diminish as it travels inland, with low to moderate PoPs (30-60%), highest along the coast and in the mid-upper RGV. Rainfall amounts should generally be less than a half an inch, but isolated higher amounts to 2.5 inches are possible under heavier showers. Rain chances diminish Friday. Saturday, another upper level disturbance will interact with a plume of moist air, bringing low PoPs (20% or less) to the region. Rain chances increase again early next week ahead of an approaching trough.

High pressure will maintain mostly fair weather outside of showers. Temperatures remain seasonable with highs in the upper 80s and lows in the 60s to low 70s.

AVIATION

(00Z TAFS) Issued at 626 PM CDT Wed Oct 21 2026

Unsettled conditions for the 00Z TAF cycle. Showers and thunderstorms over the coast are anticipated to traverse inland and increase rain chances at all sites into Thursday afternoon. An isolated shower cannot be ruled out tonight through Thursday, but the most likely timing and greatest chances (30% or less) are denoted by PROB30s at each site. Confidence in shower coverage is rather low, thus decreased timing confidence. Any heavier shower that passes over an airfield can bring MVFR-IFR ceilings and visibility, heavy rain, or lightning.

Increased moisture could bring MVFR to LIFR ceilings overnight. The most likely timeframe for any degraded cigs is between 08Z through 13Z, but may linger on either end. All sites (MFE, HRL, BRO) could see MVFR or further degraded conditions in this timeframe, with highest confidence at MFE.

MARINE

Issued at 1049 PM CDT Wed Oct 21 2026

Gentle to moderate onshore winds prevail, with seas decreasing to slight through Thursday. There is a low to medium (20-60%) chance of rain Thursday, with highest chances near the coast. Occasional moderate gusts may bring intermittent Caution conditions each afternoon through Saturday. Winds increase and seas build to moderate this weekend ahead of an approaching trough, returning adverse marine conditions.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 86 73 84 69 / 40 20 30 0 HARLINGEN 86 71 84 67 / 30 20 30 0 MCALLEN 90 73 87 68 / 10 20 40 0 RIO GRANDE CITY 90 71 88 66 / 0 10 40 0 SOUTH PADRE ISLAND 80 74 79 74 / 40 40 20 0 BAYVIEW/PORT ISABEL 83 71 82 68 / 40 40 30 0

BRO WATCHES/WARNINGS/ADVISORIES

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