textproduct: Austin/San Antonio

KEY MESSAGES

- Moderate to major heat risk forecast through the middle of this week with heat indices near or exceeding 100 degrees.

- Low chances (10-20 percent) for isolated severe storms through Tuesday.

- Cooler temperatures and higher rain chances late week.

SHORT TERM

(Tonight through Monday night) Issued at 1259 PM CDT Sun Apr 26 2026

Mainly dry, hot and humid conditions for the short term forecast. The dryline again moves into Val Verde County this afternoon extending into Central Texas. Ahead of this feature, a capped atmosphere remains in place with hot, humid and hazy conditions similar to yesterday. Highs in the 90s are forecast today with heat index values in the upper 90s to around 105 degrees. Over the Rio Grande Plains, even slightly higher heat indices may be seen up to around 107 degrees. Late this afternoon and evening, we'll again have to watch for isolated thunderstorm initiation near the dryline, though confidence for development remains low given the cap holding previous days which is reflected in the low PoPs (around 10-15%). However, if a thunderstorm does manage to develop it will be capable of producing large hail and strong wind gusts.

Low clouds build back over the area late tonight into Monday with low temperatures creeping up another degree as our heat continues to ramp up. Some guidance is generating storms early tomorrow morning along the retreating dryline northwest of our CWA, but eventually moving into our area. Added some very low PoPs over the far northwest portion to account for this uncertainty.

For the rest of the day Monday, a Pacific front/dryline moves a bit further east into the area than previous days possibly reaching into the western Hill Country. While any type of synoptic forcing will be well north of our area, cannot rule out an isolated thunderstorm with severe potential near this feature on Monday afternoon or even Monday night. The main story Monday (and into the middle of the week) continues to be the heat. Highs bump up into the low 90s over the Hill Country and portions of the southern Edwards Plateau, mid 90s over the I-35 and the Coastal Plains and into the upper 90s to possibly 100 degrees along the Rio Grande. Heat index values remain below Heat Advisory criteria both today and Monday, but taking heat safety precautions continues to be advised given its only late April.

LONG TERM

(Tuesday through next Sunday) Issued at 1259 PM CDT Sun Apr 26 2026

Tuesday is forecast to be the hottest day of the week with moderate to major heat risk over South Central Texas. Most of the area will see heat indices in the triple digits in the afternoon with humid conditions in place. With the dryline to our west and a front moving into North Texas later in the day there remains the potential for some strong to severe thunderstorms, generally favored over the southern Edwards Plateau, Hill Country into the I-35 corridor where SPC has a Level 1 of 5 risk for severe storms.

Hot conditions continue into Wednesday before we finally get some relief and a pattern change in the form of a cold front moving into our area from the north. This front looks to move into the area sometime in the afternoon or evening hours which may impact forecast temperatures this day. Additionally, this front brings widespread precipitation chances to the area which linger through Saturday as the front stalls late week somewhere in South Texas. Details with this late week system are still a bit uncertain but it does seem plausible that the potential for some strong to severe storms remains into Thursday along with locally heavy rainfall. Temperatures trend down late week with cool conditions in the 70s forecast over the weekend.

AVIATION

(18Z TAFS) Issued at 1259 PM CDT Sun Apr 26 2026

The capping inversion remains strong with hazy morning conditions continuing. We'll continue to see long hours of MVFR CIGs and today's satellite visibility view of thick coverage suggests that VFR conditions may still be 2 or 3 hours away. Will otherwise continue a general persistence strategy with the MVFR conditions returning again by 06-07Z near I-35 and around 11Z at DRT.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 74 92 73 94 / 10 20 20 20 Austin Bergstrom Intl Airport 73 93 73 95 / 10 20 20 10 New Braunfels Muni Airport 72 93 73 95 / 10 10 10 10 Burnet Muni Airport 72 90 71 91 / 10 20 20 20 Del Rio Intl Airport 74 97 75 98 / 10 0 10 10 Georgetown Muni Airport 73 92 72 93 / 10 20 20 20 Hondo Muni Airport 72 95 72 96 / 10 10 10 10 San Marcos Muni Airport 73 94 73 95 / 10 20 10 10 La Grange - Fayette Regional 74 92 74 94 / 0 10 10 10 San Antonio Intl Airport 74 94 74 96 / 10 10 10 10 Stinson Muni Airport 74 95 75 96 / 10 10 10 10

EWX WATCHES/WARNINGS/ADVISORIES

None.