textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1226 AM CDT Wed Jun 17 2026

- Flood risk has also decreased, but an isolated flash flood or two cannot be ruled out (especially in areas that already received large rainfall totals).

- Heat Risk will be a concern starting Wednesday, with the worst days being Thursday and Friday. A Heat Advisory is in effect from 1 PM to 8 PM Wednesday. Extreme Heat Warnings are possible Thursday and Friday.

DISCUSSION

Issued at 1107 PM CDT Tue Jun 16 2026

The low pressure system responsible for the recent rainfall has moved off the coast and drier conditions are forecast for the next couple days. The combination of compressional heating and increased daytime heating will likely result in high temperatures climbing to the upper 90s to low 100s through Friday. Humidity values are forecast to stay elevated through the end of the week, with dewpoints ranging from the upper 70s to low 80s. This combination will likely result in dangerous heat over the next several days. Heat index values climb to 110-115 degrees Wednesday afternoon across the Rio Grande Valley and along the coast, requiring a Heat Advisory. Thursday will likely be the hottest day, with heat index values forecast to range from 116-124 degrees across Deep South Texas., likely requiring and Extreme Heat Warning. Heat index values are forecast to range from 11-118 degrees Friday afternoon, with Heat Advisories or Extreme Heat Warnings likely.

A weak upper level disturbance is forecast to move across Texas over the weekend, bringing low (15-30%) rain chances across the western half of the CWA Friday night and Saturday. Rain free conditions are forecast to prevail through the remainder of the period.

The National Hurricane Center has potential Tropical Cyclone One forecast to become a Tropical Depression over the northwestern Gulf Wednesday morning. No impacts are anticipated for Deep South Texas.

AVIATION

(06Z TAFS) Issued at 1226 AM CDT Wed Jun 17 2026

Generally VFR will prevail at the aerodromes through the next 24 hours. Backing winds will occur as low pressure along the Texas coastline moves farther away.

MARINE

Issued at 1107 PM CDT Tue Jun 16 2026

Generally favorable marine conditions are forecast to persist through the remainder of the week, though a slight increase in wind speeds and wave heights over the offshore Gulf waters will be possible tonight and Wednesday. The National Hurricane Center has potential Tropical Cyclone One forecast to become a Tropical Depression over the northwestern Gulf Wednesday morning. However significant impacts are not anticipated along the Lower Texas Coast.

Wind speeds and seas are forecast to increase early next week and Small Craft Advisories or Small Craft Should exercise Caution headlines may be needed.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 96 83 97 84 / 0 0 0 0 HARLINGEN 96 80 98 81 / 0 0 0 0 MCALLEN 97 81 101 83 / 0 0 0 0 RIO GRANDE CITY 97 79 103 81 / 0 0 0 0 SOUTH PADRE ISLAND 91 85 91 85 / 10 0 0 0 BAYVIEW/PORT ISABEL 95 82 96 83 / 10 0 0 0

BRO WATCHES/WARNINGS/ADVISORIES

TX...Heat Advisory from 1 PM this afternoon to 8 PM CDT this evening for TXZ251>255-351-353>355.

GM...None.