textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 520 AM CDT Sat Sep 5 2026

- Low to medium (15-40%) rain and storm chances for weekend and Labor Day to mainly favor the Coastal Plains and Southern Edwards Plateau

- Daily sea breeze shower and storm chances in the Coastal Plains through much of next week

- Humid conditions with above average temperatures and peak heat indices continue

SHORT TERM

(Today through Sunday) Issued at 1225 AM CDT Sat Sep 5 2026

Mid-level spin (vort) over the region yesterday from the leftovers of Edouard will continue to drift towards the south-southwest and loses influence to the region. However, some additional spin aloft then approaches the region out of the northwestern Gulf tonight through Sunday thanks to a TUTT low. The moisture levels over the region stay elevated (75th to 90 percentile range for this time of year) with PWATs mainly in the 1.8 to 2.0 inch range. This would support low to medium (15-40%) rain chances over the region but lifting mechanisms lack a bit. Chances will favor the Southern Edwards Plateau into the Western Hill Country with the help from orographic lift and through the Coastal Plains with the sea breeze and any streamer activity coming off the coast. Chances trend the lowest for much of the I-35 corridor, where the majority stay rain free today. Sunday offers slightly better chances but still look lower compared to the Coastal Plains and the Southern Edwards Plateau. Rain amounts are expected to be mostly below a tenth to quarter inch outside of a locally heavier shower or storm.

Yesterday, early day light rain and sprinkles along with lingering cloud cover provided some heat relief to areas east of the Rio Grande and Southern Edwards Plateau. This does not look to be the case today or Sunday but most locations still look to remain below the century mark, with highs in the mid to upper 90s. It remains humid though, as result of the elevated moisture, resulting in afternoon heat indices in the 102 to 107 degree range for areas along and east of the I-35 corridor and into portions of the Rio Grande Plains. Nights will stay warm with the lows in the 70s. The persistent southeasterly flow remains fairly light, but there will be slight increases in the breeziness near and just after sunset with the passage of the sea breeze.

LONG TERM

(Sunday night through Friday) Issued at 1225 AM CDT Sat Sep 5 2026

Moisture will stick around across the region from Labor Day into much of next week but does lower slightly more to near the 1.6 to 1.9 inch range. Moisture will be highest, as typical, across the Coastal Plains closer to the coast. The moisture and a light to moderate southeasterly low-level flow remains enough to promote daily chances for isolated to scattered rain showers and storms across the Coastal Plains, east of the I-35 corridor. Some of the latest guidance picked up on the possibility for perhaps another weak inverted trough approaching from the Northern Gulf into late week from Thursday through Friday. Right now, will elect to keep rain and storm chances mostly remain confined across the coastal plains through this period. The heat stays persistent with the afternoon highs in the mid to upper 90s with the heat indices highest along/east of I-35 and across the Rio Grande Plains. The morning lows hold in the 70s, with a few approaching 80 degrees at times.

AVIATION

(12Z TAFS) Issued at 520 AM CDT Sat Sep 5 2026

Other than MVFR cigs for KSAT and possibly at KSSF for a few hours (through 14Z), I am forecasting for VFR conditions for the rest of the day into late tonight. A southerly wind flow (10 knots or less) is forecast to dominate the local sites through this cycle. Any shower or storm activity that develops today is forecast to stay away from terminals for no impacts.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 98 77 97 77 / 10 10 20 10 Austin Bergstrom Intl Airport 97 76 96 75 / 10 10 20 10 New Braunfels Muni Airport 97 76 97 75 / 10 10 20 10 Burnet Muni Airport 95 74 96 74 / 10 10 20 10 Del Rio Intl Airport 98 78 97 77 / 10 10 20 10 Georgetown Muni Airport 97 76 97 76 / 10 10 30 0 Hondo Muni Airport 97 75 96 74 / 20 10 30 10 San Marcos Muni Airport 97 75 97 74 / 10 10 20 10 La Grange - Fayette Regional 96 76 96 76 / 20 10 40 10 San Antonio Intl Airport 97 78 97 77 / 10 10 20 10 Stinson Muni Airport 99 78 98 77 / 10 10 20 10

EWX WATCHES/WARNINGS/ADVISORIES

None.