textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1008 PM CDT Fri Aug 14 2026

- Moderate to major risks of heat-related illnesses (levels 2/4 and 3/4) on Saturday improve to moderate from Sunday through next Wednesday before deteriorating to a major risk by next Thursday.

- Special Weather Statements (SPSs) for heat indices of 108-111 F remain possible, especially by the middle of next week as widespread inland high temperatures in the low to mid 100s (100-106 F) return and moisture content re-elevates.

- Outside of a low (15-20%) chance of rain across the lower and mid RGV along the afternoon seabreeze Sunday and next Monday, conditions are expected to remain dry.

- The combination of breezy southeasterly winds coinciding with low afternoon minimum relative humidity values brings a sustained risk of fire weather into next week.

- A medium risk of life-threatening rip currents persists through Saturday afternoon.

DISCUSSION

Issued at 1008 PM CDT Fri Aug 14 2026

A strong 597+ dam high pressure aloft over the Deep South slowly shifts westward to the Southern Plains throughout the weekend and begins to weaken next week, but still maintains elevated heights over Deep South Texas throughout the forecast period. Aside from a series of weak mid-level inverted shortwave troughs bringing a low (15-20%) chance of rain across portions of the lower and mid RGV from potential isolated afternoon seabreeze convection on Sunday and Monday, conditions are expected to remain mostly dry. Meanwhile, at the surface, a high pressure settles over the central Gulf coast, transitioning southeasterly and south- southeasterly winds to mainly east-southeasterly, gusting up to 15-25+ mph by Saturday afternoon, continuing into possibly next Tuesday. Altogether, this set up is expected to retreat widespread inland high temperatures in the low/mid 100s westward to the I-69 E corridor this weekend into Monday as well as improve risks of heat related illnesses from moderate to major on Saturday to mainly moderate with pockets of major from Sunday into next Wednesday. Maximum daytime heat indices of around 105-111 F are anticipated during this timeframe as well.

Towards the middle part of next week, southeasterly winds return and enhance gusts back to around 25-35+ mph as the surface high pressure shifts southward to the central Gulf and surface heights lower over the Sierra Madre lower again. Unfortunately, this could cause widespread inland high temperatures in the low/mid 100s (around 100-106 F, highest across the Rio Grande Plains) to return by next Wednesday and worsen risks of heat-related illness back to mostly major by next Thursday. Additional SPSs, for locations expecting heat indices of 108-111 F, remain possible throughout the forecast, especially toward the later parts of next week.

Fire weather concerns prevail as well, particularly during the afternoon hours, when 20-foot winds of around 10-15+ mph, gusting to 20-30+ mph, coincide with relative humidity minimizing around 25-50 percent, driest furthest west/northwest and vice versa.

A medium risk of rip currents continues through Saturday afternoon.

AVIATION

(00Z TAFS) Issued at 605 PM CDT Fri Aug 14 2026

South-southeasterly winds of around 16-20 knots, gusting to 25-30 knots this evening steadily decrease tonight to around 7-10 knots late tonight and early tomorrow morning before picking up to around 10-15 knots, gusting to 20-25 knots tomorrow afternoon. VFR conditions prevail with dry conditions.

MARINE

Issued at 1008 PM CDT Fri Aug 14 2026

Small Craft Exercise Caution (SCEC) conditions are likely to subside overnight tonight as moderate to fresh southeasterly winds become gentle to moderate by Saturday morning, while moderate seas (3-5 ft) persist, easing to slight to moderate (2-4 ft) by Sunday morning. Moderate to fresh southeasterly winds and moderate (3-5 ft) seas, with possible periods of SCEC, return by the middle of next week. Despite a low (15-30%) chance of rain on Sunday and a low to medium (20-40%) chance next Monday, mainly dry conditions should prevail.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 82 96 80 96 / 0 0 10 10 HARLINGEN 79 99 77 98 / 0 0 10 20 MCALLEN 82 103 81 102 / 0 0 0 20 RIO GRANDE CITY 80 103 78 102 / 0 0 0 10 SOUTH PADRE ISLAND 82 89 81 89 / 0 0 10 10 BAYVIEW/PORT ISABEL 80 95 79 94 / 0 0 10 10

BRO WATCHES/WARNINGS/ADVISORIES

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