textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 1242 PM CDT Tue Sep 8 2026

- Daily sea breeze rain chances in the Coastal Plains through the rest of the week with spotty chances extending into South Central Texas.

- Humid conditions with above average temperatures and elevated heat indices will continue.

SHORT TERM

(Tonight through Wednesday night) Issued at 1242 PM CDT Tue Sep 8 2026

Weakly southeasterly flow in the mid-levels is aiding the movement of diffuse moisture from the Gulf towards South Central Texas. This supports chances for spotty showers this afternoon and early evening mainly between the Coastal Plains and I-35 corridor. Condition remain hot within this moist environment and a few spots could briefly exceed 108F for heat indices later this afternoon.

The overall pattern does not change substantially for Wednesday with a humid heat continuing to be favored. The latest hi-res guidance suggests there may be slightly more cloud cover thanks to a weak inverted trough passing through the area from the Gulf, but cooling from clouds alone will be fairly minimal. That weak disturbance will help bring another chance for spotty showers and thunderstorms Wednesday afternoon and evening. Chances are best over the Coastal Plains (up to 40%), but given weak capping and broadly moist atmospheric profiles, chances for isolated rains extend to the I-35 corridor and Hill Country. This is reflected in both HREF and REFS members, and sporadic shower or storm activity could reach as far west as the southern Edwards Plateau tomorrow afternoon.

LONG TERM

(Thursday through next Tuesday) Issued at 1242 PM CDT Tue Sep 8 2026

Hot and mostly dry weather is favored this week, but ridging is expected to weaken and leave the door open for low-end isolated rain chances (generally around or below 30 percent) across South Central Texas. A weak area of coastal vorticity on Thursday and residual activity/outflow boundaries from troughing or a weak front to the north on Friday are expected to be the main drivers of these spotty rain chances, along with recurring opportunities from the coastal seabreeze. While a lack of wind shear or more concentrated forcing will favor more disorganized activity, the humid air could support a briefly heavier rain.

Temperatures will stay hot and broadly above normal for early/mid September. The rain chances will bring scattershot relief from the heat for isolated areas, but otherwise highs are expected to remain in the upper 90s to low 100s. With dew points remaining elevated, heat indices are forecast to continue straddling Heat Advisory criteria at least through the week for areas outside of the Hill Country. The hottest period in the forecast could focus around Friday/Saturday when northwesterly flow aloft dislodges hotter air aloft over the southern Rockies into our area.

AVIATION

(18Z TAFS) Issued at 1242 PM CDT Tue Sep 8 2026

All terminals will be VFR through the coming TAF period. There are very low chances for a shower or thunderstorm in Austin and San Antonio this afternoon and Wednesday afternoon, but chances are too low to include anything in the TAFs. Winds will be from the south to southeast mainly less than 10 kts except at DRT where they will gust up to 20 kts during the afternoon.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 77 100 77 99 / 20 20 10 10 Austin Bergstrom Intl Airport 77 99 76 99 / 20 20 10 10 New Braunfels Muni Airport 76 98 75 98 / 20 20 20 10 Burnet Muni Airport 75 97 74 96 / 0 20 10 10 Del Rio Intl Airport 78 100 78 100 / 0 0 10 0 Georgetown Muni Airport 77 99 76 98 / 10 20 10 10 Hondo Muni Airport 75 98 74 97 / 0 10 10 20 San Marcos Muni Airport 76 99 75 98 / 20 20 20 10 La Grange - Fayette Regional 77 99 76 98 / 0 30 10 20 San Antonio Intl Airport 78 98 77 97 / 10 20 10 20 Stinson Muni Airport 78 100 77 99 / 10 20 10 10

EWX WATCHES/WARNINGS/ADVISORIES

None.