textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 200 PM CDT Tue Sep 15 2026 - A Heat Advisory remains in effect for the coastal plains, Williamson, and Travis Counties until 7 PM.

- A Rangeland Fire Danger Statement continues until 8 PM today for the Rio Grande plains and portions of the southern Edwards Plateau due to gusty southeast winds and low humidity values.

- Increased moisture Thursday into Friday brings a chance for convection to areas generally along and east of I-35.

SHORT TERM

(Tonight through Wednesday night) Issued at 200 PM CDT Tue Sep 15 2026

The forecast for today remains on track and see no reason to adjust the ongoing Heat Advisory in effect until 7 PM CDT for portions of the I-35 corridor into the coastal plains region. Southeasterly winds in the lower levels will continue tonight and again Wednesday night, leading to very warm overnight low temperatures. The NBM looked a little low with regards to lows and have bumped up temperatures slightly based on persistence. On Wednesday, it will be warm again across south central Texas. The models do show a subtle weakening of the low-level thermal ridge tomorrow, and this should allow temperatures to ease slightly. For now, we will hold off on a Heat Advisory for Wednesday.

LONG TERM

(Thursday through next Tuesday) Issued at 200 PM CDT Tue Sep 15 2026

Mid and upper level high pressure centered over the southeastern U.S. will continue to be the main influence on our weather across south central Texas through the end of the week and into early next week. A surge of low-level moisture on Thursday into Friday along with daytime heating should aid in the development of isolated to scattered convection for areas generally along and east of the I-35 corridor. The NBM pops look a bit high, but did opt to keep scattered rain chances (30-50%) over the coastal plains with rain chances closer to 20% farther west into the I-35 corridor.

Moisture levels decrease rather quickly for the upcoming weekend as the high pressure over the southeastern U.S. builds into the southern U.S. plains. The latest NBM shows some rain chances returning to a good portion of the region early next week as high pressure begins to weaken. Given the current suite of operational models, we are a bit skeptical of this. However, if a weak frontal boundary can manage to slide southward early next week, our rain chances would improve. Temperatures continue to remain above normal through the period.

AVIATION

(18Z TAFS) Issued at 1238 PM CDT Tue Sep 15 2026

VFR conditions should continue for this afternoon and evening and through the majority of the overnight hours for all TAF sites. We should see MVFR CIGs return just before daybreak (10Z) for KSAT and KSSF. For KAUS confidence isn't quite as high for seeing MVFR CIGs so have added in a TEMPO just after dawn (13Z) until late morning. Afterward expect VFR CIGS and southerly winds in the morning switching to the east by the afternoon. VFR CIGs are expected throughout the entire period for KDRT along with mainly prevailing east southeasterly winds.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 78 100 78 99 / 0 0 0 20 Austin Bergstrom Intl Airport 76 100 77 98 / 0 0 0 30 New Braunfels Muni Airport 76 99 75 97 / 0 0 0 30 Burnet Muni Airport 75 97 74 95 / 0 0 0 10 Del Rio Intl Airport 77 101 77 99 / 0 0 0 0 Georgetown Muni Airport 77 99 77 98 / 0 0 0 20 Hondo Muni Airport 74 99 74 97 / 0 0 0 10 San Marcos Muni Airport 75 100 75 98 / 0 0 0 30 La Grange - Fayette Regional 77 99 77 97 / 0 10 0 50 San Antonio Intl Airport 77 99 78 97 / 0 0 0 20 Stinson Muni Airport 77 100 77 99 / 0 0 0 30

EWX WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 7 PM CDT this evening for TXZ173-192>194-209- 225.