textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 635 AM CDT Thu Oct 1 2026

- A Flood Watch is in effect through Friday evening for most of South Central Texas.

- Some storms tonight and Thursday may also be strong to severe.

- Low to medium rain chances linger through the weekend then decrease heading into next week.

SHORT TERM

(Today through Friday) Issued at 127 AM CDT Thu Oct 1 2026

The latest GOES 19 Water Vapor imagery shows the upper low centered over New Mexico this evening and slowly marching eastward. Out ahead of it, southwesterly flow and a 40-60 kt southwesterly jet streak will slide eastward. In combination with highly anomalous PWATs in the 2-2.4" range and strong southeasterly low-level flow, showers and storms will develop this evening, and slowly march eastward, capable of intense rainfall rates. For tonight there is a level 2 of 4 (Slight) risk for flooding from the I-35 Corridor and westward, and a level 3 of 4 (Moderate) risk for the western Hill Country, Edwards Plateau, and northern Rio Grande Plains. HREF members and REFS members show storms developing out west and marching east through this morning, with torrential rainfall rates up to 2+" per hour. For what it's worth, some high res members of the WoFS and of the HRRR show storms developing over the San Antonio metro ahead of the primary line and frontal boundary.

Today, WPC places a Level 2 to 3 of 4 risk over much of south central Texas, with a Level 3 of 4 (Moderate) risk in place for the Hill Country, I-35 Corridor, southern Rio Grande Plains, and eastern parts of the Edwards Plateau. Storms are likely to be ongoing Thursday morning as a Pacific front slides south and east with time during the day. Convection may redevelop in the afternoon and evening hours today behind the initial line. It's dependent on instability behind the boundary and how far south and east it gets. If the front stalls like the GFS and NAM/NAM 3km indicate, redevelopment would occur along the I-35 Corridor Thursday night. We could see widespread rainfall amounts of 1-4" with local amounts up to 6-8" through Friday.

LONG TERM

(Friday night through Wednesday) Issued at 127 AM CDT Thu Oct 1 2026

For the weekend, some mid-level energy will remain in place which may spark additional showers and storms each day, but the intensity of storms shouldn't be quite as high as it will be today and Friday. The mid to upper level trough will get stuck over southwest Texas, resulting in those continued rain and storm chances. There may be some lingering showers Monday morning, but by the afternoon, things look dry across much of south central Texas. Essentially Monday through Wednesday of next week looks dry as weak zonal flow settles in over the region.

AVIATION

(12Z TAFS) Issued at 635 AM CDT Thu Oct 1 2026

Showers and thunderstorms are moving across the region north of our airports. The western end of the area is approaching DRT, and they will see convection over the next hour or two. Once these storms move away, they should remain rain free and VFR for the rest of this period.

There are some light rain showers in the Austin and San Antonio areas for another hour or so. Then the best timing for thunderstorms in those areas will be late morning until early afternoon. There will be high chances for rain showers through the afternoon and lower chances during the evening. More showers will develop overnight along with MVFR ceilings.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 89 72 82 69 / 90 90 80 50 Austin Bergstrom Intl Airport 90 71 82 68 / 90 90 80 50 New Braunfels Muni Airport 89 70 81 68 / 90 90 80 50 Burnet Muni Airport 82 70 79 66 / 90 60 70 50 Del Rio Intl Airport 90 69 85 65 / 50 10 30 50 Georgetown Muni Airport 87 71 80 67 / 90 80 80 50 Hondo Muni Airport 84 70 81 67 / 90 60 60 50 San Marcos Muni Airport 90 71 82 67 / 90 90 80 50 La Grange - Fayette Regional 94 72 85 70 / 90 90 80 50 San Antonio Intl Airport 87 73 81 70 / 90 80 80 50 Stinson Muni Airport 89 73 82 70 / 90 80 80 50

EWX WATCHES/WARNINGS/ADVISORIES

Flood Watch through Friday evening for TXZ171>173-183>193- 202>208-217>221-223-228.