textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 616 AM CDT Tue Sep 15 2026

- A Special Weather Statement (SPS) is in effect on Tuesday for Southern Hidalgo County as well as the inland and coastal portions of Kenedy, Willacy and Cameron counties, where heat indices are expected to reach 108-111 F, or briefly higher, generally within the hours of 12 PM to 6 PM.

- Near record-breaking heat and major to extreme risks of heat related illnesses (levels 3/4 and 4/4) continue into Wednesday, improving to a mainly moderate risk (level 2/4) by Thursday though temperatures remain above average.

- Fire weather concerns continue, most concerning Tuesday afternoon.

- Mostly dry conditions are expected through midweek, followed by a region-wide low to medium (20-40%) chances of rain Thursday into Friday and a low (10-15%) chance over the weekend before increasing just a bit early next week.

- A medium risk of life-threatening rip currents continues through Tuesday afternoon.

DISCUSSION

Issued at 1038 PM CDT Mon Sep 14 2026

A building high pressure aloft over the eastern US and a tightened pressure gradient maintain dry conditions through Tuesday as well as near-record breaking triple digit temperatures across most inland areas and breezy conditions, with southeasterly winds gusting to 25-35 mph, turning easterly and weakening a bit on Wednesday. The combination of well-above average temperatures combining with onshore, moist flow has led to the issuance of a SPS for Tuesday and an additional SPS is possible on Wednesday. Risks of heat-related illnesses continue ranging from extreme across portions of the RGV and Rio Grande Plains to mostly major elsewhere through midweek as well. Additionally, although the latest forecast conditions are expected to fall just shy of Fire Danger Statement criteria, the combination of breezy southeasterly winds coinciding with minimizing afternoon relative humidity values brings the concern of fire weather Tuesday afternoon. Outdoor burning is not recommended and high caution is urged when handling flames. As always, you can visit weather.gov/bro for the latest forecast and information regarding heat and fire safety.

Towards the later part of the week, a surge of high pressure elongating across the eastern CONUS and the Gulf advects deep Gulf moisture to deep south Texas via easterly to northeasterly winds, increasing PWAT values on Wednesday to as much as 2.0-2.4+ in. on Thursday, thus elevating chances of rain along the daytime seabreeze boundary from a low (15-20%) chance across the southern portions of the RGV on Wednesday afternoon to a mostly region-wide low to medium (20-40%) chance on Thursday and Friday, with the best chances along/east US-281. Given such high moisture content, there is a risk for localized flooding concerns on Thursday and possibly Friday, especially within any slow-moving, or training, of convection. Following, much drier air funnels into the region, leaving only a low (10-15%) chance of rain each afternoon over the weekend, though troughing arriving over Texas could lead to more nearly widespread low (15-30%) rain chances to begin next week. Although temperatures are expected to remain above average, easterly to northeasterly winds and increased cloud cover should help highs to cool off to the upper 90s to lower 100s as well as improve heat risks to mostly moderate by Thursday.

AVIATION

(12Z TAFS) Issued at 616 AM CDT Tue Sep 15 2026

VFR will prevail at the aerodromes through the next 24 hours. Breezy winds today will diminish around sunset. Limited cloud cover will also occur with rain-free skies.

MARINE

Issued at 1038 PM CDT Mon Sep 14 2026

Moderate to fresh southeasterly winds become light to gentle, occasionally moderate, by Tuesday night and transition to easterly, northeasterly at times, by Wednesday. Sight to moderate (2-4 ft) seas build to moderate (3-5 ft) Thursday through Saturday and southeasterly winds return Sunday. Chances of rain build throughout Wednesday to a medium to likely (40-80%) on Thursday and a low to medium (30-60%) chance on Friday. Chances minimize over the weekend before increasing again into the beginning of next week.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 98 80 97 80 / 0 0 10 30 HARLINGEN 102 76 100 76 / 0 0 0 10 MCALLEN 104 80 103 80 / 0 0 10 10 RIO GRANDE CITY 104 78 103 78 / 0 0 10 0 SOUTH PADRE ISLAND 90 82 89 81 / 0 0 10 40 BAYVIEW/PORT ISABEL 97 78 95 78 / 0 0 10 30

BRO WATCHES/WARNINGS/ADVISORIES

None.