textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 539 AM CDT Sat Sep 19 2026

- Low chances (15-30%) for showers or storms over the Hill Country and southern Edwards Plateau Sunday night.

- Low chances for rain across South Central Texas next week with most staying dry.

- Above average temperatures continue into late September.

SHORT TERM

(Today through Sunday) Issued at 1226 AM CDT Sat Sep 19 2026

The batch of moisture that offered spotty rain the last two days mostly south of Interstate 10 is on its way out and a drier airmass is spreading westward across South Central Texas, distinctly evident on water vapor imagery and GOES-derived TPW imagery.

This drier air aloft will set the tune for a mostly sunny Saturday with highs in the mid to upper 90s for most, with a few spots in the Rio Grande Plains reaching the low triple digits, and Sunday should be similar. Overnight lows will continue to be mild and in the 70s. The presence of mid-level ridging and this drier airmass will keep rain out of the forecast for most of the region through Sunday afternoon, though diffuse vorticity could bring an isolated weakening shower or storm into rural Val Verde County after sunset today. The ridge is expected to weaken some late this weekend into early next week as troughing moves across the western CONUS. A shortwave impulse, most apparent in the upper-troposphere, is expected to accompany some of this troughing as it moves across West/North Texas late Sunday. Most of the resulting isolated to scattered thunderstorms are favored to form north of our area, but some activity could spill into Hill Country and southern Edwards Plateau to the Del Rio area late Sunday. The risk of severe weather or excessive rainfall is low, but it will be worth being on the lookout for potential late night storminess for those areas late Sunday into early Monday.

LONG TERM

(Sunday night through Friday) Issued at 1226 AM CDT Sat Sep 19 2026

Despite some of the increased troughiness out west, the jet stream is not in an especially favorable latitude to more convincingly shove ridging out of our area. This will allow the ridge to reestablish towards midweek, keeping the overall pattern of unseasonably warm temperatures going for late September. Forecast highs remain in the mid to upper 90s with lows in the mid to upper 70s, aside from the upper 60s filtering into the higher terrain in the Hill Country. Peak afternoon heat indices are forecast to continue poking above 100F for many. While the bulk thermal energy in the low to mid troposphere isn't strongly suggestive of record-breaking heat, it does look like we will continue to straddle the upper ends of the distribution for both daytime and nighttime temperatures at least through midweek.

Rain chances stay low in the forecast for next week, but aren't entirely out of the picture and there is the possibility that the pattern could allow for recurring isolated rain chances during the early half of the week. Depending on how the convection late Sunday/early Monday evolves, residual boundaries and a band of higher 700mb theta-e may stay draped over Central Texas before it gets cycled out by the ridge. For this reason, low rain chances up to around 25 percent remain in the forecast mainly for the afternoon/early evening hours during the upcoming workweek across varying portions of South Central Texas. Recent runs of the EPS and AIGEFS lean towards slightly wetter depictions while the GEFS and ECMWF AIFS have tended to be dry, so uncertainty is still high and will hinge on how the aforementioned setup establishes. Regardless, with synoptic forcing remaining weak, rains are not expected to be widespread and most are likely to remain dry.

AVIATION

(12Z TAFS) Issued at 539 AM CDT Sat Sep 19 2026

Winds will generally remain east-southeasterly but remain less than 10 kts. Opted to leave prevailing MVFR at SAT and SSF with a tempo to account for uncertainty and a possible back and forth MVFR/VFR scenario this morning through 15Z. VFR should prevail beyond that but there is still an outside shot of MVFR stratus returning tonight after 09Z. No other major changes for this forecast update.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 100 75 100 76 / 0 0 0 10 Austin Bergstrom Intl Airport 99 74 100 75 / 0 0 0 10 New Braunfels Muni Airport 98 73 98 74 / 0 0 0 0 Burnet Muni Airport 96 72 97 72 / 0 0 0 20 Del Rio Intl Airport 99 77 99 75 / 0 10 0 20 Georgetown Muni Airport 99 74 99 75 / 0 0 0 10 Hondo Muni Airport 96 72 97 73 / 0 0 0 10 San Marcos Muni Airport 99 73 99 74 / 0 0 0 10 La Grange - Fayette Regional 98 72 99 75 / 0 0 0 0 San Antonio Intl Airport 96 75 97 76 / 0 0 0 10 Stinson Muni Airport 98 74 99 75 / 0 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

None.