textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 1220 AM CDT Thu Aug 27 2026

- A Heat Advisory is in effect through this evening for the Coastal Plains and I-35 corridor.

- Low to medium rain/storm chances for most areas Thursday and some locations Friday. Otherwise, hot and predominantly dry weather persists.

SHORT TERM

(Today through Friday) Issued at 1220 AM CDT Thu Aug 27 2026

Ridging will continue to very gradually move westward today, eventually centering itself near the New Mexico/Arizona boarder. Flow aloft turns northerly to northwesterly in this pattern allowing some disturbances to ride the eastern periphery of the ridge. This brings both increased moisture and rain chances to the majority of South Central Texas today. Increased moisture and forecast highs in the 90s to around 103 degrees will allow for heat index values to rise with the highest values over the Coastal Plains and I-35 corridor. A Heat Advisory continues for these locations through this evening. Cloud cover and any shower and thunderstorm activity may impede on forecast high temperatures/heat indices, but any which way you look at it, summer-time heat will be in place.

Back to rain chances: Guidance shows a disturbance and surface boundary moving south-southeast towards the area as early as this morning, as evident from activity developing to the north of the Waco area as of the writing of this discussion. However, the higher and more widespread precipitation chances are seen this afternoon and evening with peak heating. Isolated to scattered coverage is expected meaning not everyone will receive rain. At least some activity could linger overnight into Friday though only isolated activity is expected during this time. Severe storms are not likely, though stronger storms could produce gusty wind and locally heavy rainfall. Additionally, the return of some seabreeze showers or storms will be possible Friday. Temperatures on Friday should decrease a few degrees, though lingering moisture will still allow heat index values to approach the 105-108 degree mark for some locations.

LONG TERM

(Friday night through Wednesday) Issued at 1220 AM CDT Thu Aug 27 2026

Drier conditions return this weekend as ridging builds back east, though this feature does look to weaken the latter half of the weekend. Guidance indicates a disturbance moves westward towards the Texas Gulf coast early next week, though there isn't great agreement on timing or its strength. This feature could bring back some low rain chances to the area, primarily to the east of the I-35 corridor, and keep temperatures more seasonably hot than compared to the last week.

AVIATION

(06Z TAFS) Issued at 1220 AM CDT Thu Aug 27 2026

VFR conditions should primarily continue but we will monitor for possible rain and convection potential during portion of the TAF period. A disturbance and surface boundary to the north of Waco has begun to form showers and isolated convection at the time of this discussion. This activity pushes south-southeastward into and through the early to mid-morning. Activity could possible get close to KAUS, and have added VCSH as a result beyond 09 UTC. The best opportunity for showers and convection occur from the afternoon into this evening with daytime heating at each of the sites. Have inserted PROB30 groups with -TSRA and variable higher winds due to any nearby convection at each of the TAF sites as a result. Expect for the activity to diminish around the I-35 sites by around 02 UTC while KDRT is later on timing with activity may persist as late as the 06 UTC hour. Couldn't rule out MVFR for brief period but confidence is too low to include in the TAF package at this time. Otherwise, do expect increasing cloud cover as well, mainly in the mid to high cloud variety.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 103 78 101 77 / 40 20 10 10 Austin Bergstrom Intl Airport 103 77 100 77 / 40 30 10 10 New Braunfels Muni Airport 102 75 100 75 / 50 30 20 10 Burnet Muni Airport 100 75 97 74 / 30 20 10 0 Del Rio Intl Airport 102 77 100 77 / 10 30 20 0 Georgetown Muni Airport 102 77 99 77 / 20 20 10 0 Hondo Muni Airport 101 75 99 74 / 40 30 30 10 San Marcos Muni Airport 102 76 100 75 / 50 30 20 10 La Grange - Fayette Regional 103 77 99 76 / 50 30 20 10 San Antonio Intl Airport 101 78 99 77 / 40 30 20 10 Stinson Muni Airport 103 79 101 77 / 40 30 20 10

EWX WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 7 PM CDT this evening for TXZ173-191>194- 205>209-220>225.