textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1208 AM CDT Thu Aug 13 2026

- A Special Weather Statement (SPS) is likely and a Heat Advisory is possible on Thursday, with additional potential SPSs into next week.

- Aside from a low (15-20%) chance of rain along the seabreeze boundary on Friday and next Monday, dry and breezy to gusty conditions continue.

- Slightly adverse marine conditions prevail through Friday.

- Elevated risk of rip currents at the local beaches.

DISCUSSION

Issued at 1038 PM CDT Wed Aug 12 2026

A series of mid/upper level shortwaves translating across the Plains, embedded within the ridge of a building and expanding area of high pressure aloft over the Deep South, leads to another breezy and gusty day on Thursday, with 20-25 mph southeasterly winds gusting to 30-35+ mph, resulting in strong warm air and Gulf moisture advection into our region into Friday. The combination of hot temperatures (highs in the low/mid 100s, highest over the Rio Grande Plains) and enhanced moisture content are likely to lead to at least a SPS for heat indices of around of 108-111 F across portions, or all, of inland and coastal deep south Texas (not including the barrier islands) on Thursday. Additionally, the counties along/near I-69 E may even be placed under a Heat Advisory, where apparent temperatures could soar to 111-114 F, or slightly warmer, for several hours. The overnight and/or the Thursday morning crew will continue to assess and determine the best route to take in which heat-related products to issue, so stay tuned.

Similar air temperatures are in store for Friday and mainly dry conditions are likely through the middle of next week. However, as the high pressure aloft builds and expands westward, embedded weak mid/upper level troughs could generate a low (15-20%) chance of rain along the seabreeze boundary on Friday and next Monday, mainly along/east of US-281/I-69 C. Additionally, a surface high pressure settling over the coastal Deep South and loosening pressure gradient are progged to transition southeasterly winds to east-southeasterly and steadily weaken this weekend, thus slightly reducing warm air and moisture advection, causing risks of heat-related illnesses to become mostly moderate, with pockets of major, by Sunday as heat indices reduce to around 105-111 F. Heat Advisories are currently not expected onward from Friday, but SPSs certainly remain possible.

Due to ongoing and expected intensification of breezy winds on Thursday, at least a moderate risk of rip currents continues tonight through Thursday afternoon, though may be elevated to a high risk by the oncoming shifts.

AVIATION

(06Z TAFS) Issued at 1208 AM CDT Thu Aug 13 2026

VFR conditions are expected at all airports throughout the TAF period. Winds will be overall light to moderate and southeasterly, but could become gusty between 14z and 16z.

MARINE

Issued at 1038 PM CDT Wed Aug 12 2026

Small Craft Exercise Caution (SCEC) headlines tonight may become Small Craft Advisory across the Laguna Madre and the Lower Texas nearshore Gulf waters (0-20 nm) on Thursday as moderate to fresh southeasterly winds become fresh to strong along with moderate (3-5+ ft) seas. Moderate to fresh southeasterly winds resume on Friday, becoming mainly gentle to moderate by Saturday, with periods of SCEC still possible into next week along with slight to moderate (2-4 ft) seas. Aside from a low (15-30%) chance of rain late tonight, over this weekend and into the beginning of next week, likely limited to the offshore Gulf waters (20-60 nm), conditions are expected to remain dry.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 97 82 96 82 / 0 10 20 0 HARLINGEN 100 79 99 78 / 0 10 20 0 MCALLEN 103 82 102 82 / 0 0 10 0 RIO GRANDE CITY 104 80 102 79 / 0 0 10 0 SOUTH PADRE ISLAND 90 81 90 82 / 0 10 10 0 BAYVIEW/PORT ISABEL 97 80 96 80 / 0 10 10 0

BRO WATCHES/WARNINGS/ADVISORIES

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