textproduct: Austin/San Antonio

KEY MESSAGES

- More widespread rain chances return Sunday through Thursday with locally heavy rainfall possible.

- Increasing humidity and heat indices through Tuesday, with some spots feeling like 100-105+ Sunday, Monday, and Tuesday.

SHORT TERM

(Tonight through Friday night) Issued at 129 PM CDT Thu May 14 2026

Southerly winds have ramped up early this afternoon as a surface low develops over the Texas Panhandle. Further west, a dryline will sharpen over west Texas, sparking showers and thunderstorms this evening. There is an outside chance a lone storm or two could work into Val Verde County late this evening, enough to include some 20% PoPs over the western portion of the county. Shortwave ridging will start to slide east on Friday, allowing additional showers or storms to try and enter Val Verde County Friday evening. For now, we will carry some 20% PoPs for western Val Verde Friday evening as well. Several members of the HREF support this possibility, so it feels prudent to include at least some low end PoPs, despite uncertainty in whether convection will get that far east this evening or Friday evening. In terms of temperatures, highs will climb into the upper 80s to middle 90s today and Friday along with partly to increasingly cloudy skies on Friday afternoon. Expect breezy southeasterly winds to continue through the entire short term forecast period as humidity steadily increases through the day Friday.

LONG TERM

(Saturday through next Thursday) Issued at 129 PM CDT Thu May 14 2026

The weekend and into next week is when the pattern get more interesting and certainly busier. Large scale troughing over the western CONUS will steadily slide eastward, finally working east of the Rockies by late in the weekend. This will set the stage for continued moisture return northward into South Central Texas. Ensemble ECMWF and GEFS PWATs along with LREF PWATs are easily some 1-2.5 SDs above the mean for late May, and around 125-165% of normal. As anomalously high moisture works into the region, it will send heat indices into the 100-105+ range Sunday through Tuesday, particularly over the Rio Grande Plains. Heat safety will need to be stressed, particularly over the RG Plains where air temperatures in the mid 90s coupled with dewpoints in the low to mid 70s will make it feel quite a bit hotter.

Sunday may feature some streamer showers due to increasing warm air advection ahead of the approaching troughing and surface low over north Texas. Capping should hold strong Sunday afternoon and evening and the forecast is mostly dry because of this. By Monday, things start to get more interesting as southwesterly flow aloft increases and a series of shortwaves ripple through the long wave flow. This will result in several rounds of showers and storms, with locally heavy rainfall the primary concern through midweek.

AVIATION

(18Z TAFS) Issued at 1217 PM CDT Thu May 14 2026

Gusty south to southeast winds and VFR skies will continue through this afternoon and early evening. Wind gusts should ease closer to sunset as winds back to a more east to southeasterly direction. For early Friday morning, confidence has increased enough to warrant a TEMPO group for MVFR cigs along the I-35 corridor. Low clouds are not expected to make it out west to DRT, so kept the forecast VFR there. Gusty south to southeast winds return to all sites by late morning Friday along with VFR skies.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 69 91 71 91 / 0 0 0 0 Austin Bergstrom Intl Airport 69 91 72 91 / 0 0 0 0 New Braunfels Muni Airport 67 92 70 91 / 0 0 0 0 Burnet Muni Airport 68 88 69 88 / 0 0 0 0 Del Rio Intl Airport 72 94 72 92 / 0 0 0 0 Georgetown Muni Airport 69 90 71 89 / 0 0 0 0 Hondo Muni Airport 67 91 69 91 / 0 0 0 0 San Marcos Muni Airport 68 91 71 91 / 0 0 0 0 La Grange - Fayette Regional 69 92 71 90 / 0 0 0 0 San Antonio Intl Airport 68 92 71 91 / 0 0 0 0 Stinson Muni Airport 69 92 71 92 / 0 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

None.