textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 1238 PM CDT Mon Aug 31 2026

- Dry and hot today with limited shower activity across the Coastal Plains.

- Potential Tropical Cyclone 5 located across the northern Gulf and south of Louisiana to move northwestward as it approaches the upper Texas and southwest Louisiana coasts by Tuesday morning. This system could become a tropical cyclone within the next 24 hours.

- Rainfall amounts associated with PTC 5 could impact the eastern part of the local area especially locations east of the I-35 corridor and Coastal Plains on Tuesday and Wednesday. Forecast rainfall amounts over most places range from one half inch or less with isolated pockets of 1 to 2 inches possible.

- Additional episodes of showers and thunderstorms are possible Thursday into the weekend as an upper level disturbance pushes westward over the northern Gulf.

SHORT TERM

(Tonight through Tuesday night) Issued at 1220 PM CDT Mon Aug 31 2026

Morning clouds are forecast to erode for most of the local area by early afternoon. Then, clouds redevelop mid to late afternoon with the heating of the day and increased moisture arriving from the Gulf. We are calling for a dry period today, however, can't rule out an isolated shower or two with the seabreeze over parts of the Coastal Plains. Otherwise, forecast highs ranging from the mid to upper 90s and up to 102 along the I-35 corridor and up to 104 for parts of the Rio Grande Plains. Maximum heat index values range from the 103 to 107. Some areas along the Coastal Plains and portions of the Rio Grande could briefly get into the 108 to 110 for an hour or less.

Clouds continue to develop this evening into Tuesday morning. Forecast overnight lows range from the lower to upper 70s. As the day progresses, increased moisture arrives to the eastern part of South Central Texas as PTC 5 nears the upper Texas coast. Isolated showers and thunderstorms could be affecting areas along Highway 77 as early as noon or shortly after. This activity is forecast to push westward throughout the afternoon as it nears the I-35 corridor. Can't rule out a quick heavy downpour during this time frame capable of producing an inch of rainfall. Widespread rainfall is not expected with most areas getting from limited to one half inch. Tuesday's highs are forecast to be slightly cooler especially across the east of the I-35 corridor from those today due to increased moisture and cloud coverage. Tuesday's highs reaching the lower to upper 90s and up to 103 over portions of the Rio Grande.

LONG TERM

(Wednesday through next Monday) Issued at 1220 PM CDT Mon Aug 31 2026

By Wednesday, the remnants of PCT 5 are forecast to be moving over east-central Texas. Some of that moisture is forecast to affect part of South Central Texas especially areas along and east of Highway 77. As mentioned above, rainfall accumulations are likely to concentrate to the east of the I-35 corridor and likely to areas along and east of Highway 77. High temperatures are forecast to be very similar for the long term period at least from Wednesday through the weekend. There are new opportunities for rain on Thursday through Saturday as an upper level disturbance moves across the northern Gulf. Rain chances favoring the Coastal Plains along with seabreeze activity.

AVIATION

(18Z TAFS) Issued at 1238 PM CDT Mon Aug 31 2026

VFR conditions are favored for most through tonight. Spotty SHRA/TSRA is possible with the seabreeze this evening near KSAT/KSSF, but chances of impacting those terminals are below 20 percent. Potential Tropical Cyclone Five will near the region tomorrow afternoon. Its compact wind field is not expected to be felt for most of the area, but its influence will produce light easterly prevailing winds. Scattered SHRA/TSRA is possible mainly near KAUS after 18Z Tuesday, and may be introduced in later TAFs should confidence increase.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 77 99 77 100 / 0 10 10 10 Austin Bergstrom Intl Airport 77 99 77 100 / 0 10 10 10 New Braunfels Muni Airport 75 98 75 100 / 0 0 0 10 Burnet Muni Airport 74 96 74 97 / 0 10 0 10 Del Rio Intl Airport 78 100 78 102 / 0 0 0 0 Georgetown Muni Airport 77 98 76 99 / 0 10 10 10 Hondo Muni Airport 74 98 74 99 / 0 0 0 0 San Marcos Muni Airport 76 99 75 100 / 0 10 10 10 La Grange - Fayette Regional 78 99 77 99 / 0 20 40 20 San Antonio Intl Airport 77 98 77 100 / 0 0 0 0 Stinson Muni Airport 76 100 77 102 / 10 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

None.