textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 534 AM CDT Sat Aug 22 2026

- Heat Advisory in effect for the northern Hill Country, I-35 Corridor, and Coastal Plains through Sunday.

- Brief and isolated showers and storms possible over Central Texas this afternoon.

- August heat wave continues with no significant rain or heat relief in sight.

SHORT TERM

(Today through Sunday) Issued at 1204 AM CDT Sat Aug 22 2026

The forecast has long called for a hot weekend and it that won't be changing as upper level ridging remains steady over the southern Rockies and southern Plains. A Heat Advisory remains in effect through the weekend for the northern Hill Country, I-35 corridor, and Coastal Plains. For these areas, high temperatures both Saturday and Sunday are expected to rise into the 102F to 105F range with heat indices up to about 109F. These conditions can become dangerous if adequate steps are not taken to stay cool and hydrated. Overnight temperatures stay in the mid to upper 70s within the advisory areas, providing meager relief.

While the atmospheric profile looks relatively dry with a patch of modest precipitable water extending from West Texas into the Central Gulf, the weakly anticyclonic flow around the nearby upper level ridge will help push a zone of slightly higher moisture straddling a baroclinic zone aloft near our region today. The slight rise in moisture results in convective temperatures in the latest HREF to be subtly lower this afternoon compared to Friday, ranging generally between 100-103F. This implies daytime heating alone may be sufficient to spark a few isolated and gusty shower or even a brief thunderstorm this afternoon. Rain chances remain on the low side (15 to 20 percent) and focused over the Hill Country to Austin metro area, but is depicted in some of the hi- res models. Any shower would likely be brief, but the accompanying gustiness and rain could bring temporary respite from the heat. The baroclinic support is lower for Sunday, so chances look lower for this type of isolated shower activity.

LONG TERM

(Sunday night through Friday) Issued at 1204 AM CDT Sat Aug 22 2026

The heat wave won't be going away anytime soon. Without any notable amplification of the jet stream to its north, the strong ridge keeping our hot airmass in place doesn't have any travel plans this upcoming week. High temperatures will continue to be near or over 100F each day, with only slight fluctuations day to day. Regardless of whether the scales tip towards additional Heat Advisory extensions/issuances or not, the bottom line is that the summer heat continues.

The forecast remains dry as subsidence from the ridge prevents shower formation, though there could be some potential for a few showers to sneak into the region Friday as the tail end of a decaying front brushes the area. Otherwise, the current weather pattern offers slim pickings for rain through the end of August.

AVIATION

(12Z TAFS) Issued at 534 AM CDT Sat Aug 22 2026

VFR flight conditions prevail through the period. A few patchy low clouds may develop after sunrise this morning and again into Sunday morning but not expecting any flight impacts across the area terminals. Otherwise, there will be some passing high level clouds, mainly into and through this morning and again later tonight into early Sunday. This afternoon with daytime heating perhaps could see a stray shower or storm pop up in the northern portions of the region, but not expecting any impacts for the local TAF sites. We'll monitor KAUS the most to see if anything tries to approach. Winds remain light at around 10 kt or less with directions from the south-southwest to out of the east- southeast along the Rio Grande.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 105 79 105 79 / 10 10 0 0 Austin Bergstrom Intl Airport 104 77 104 78 / 10 10 0 0 New Braunfels Muni Airport 103 76 103 76 / 10 0 0 0 Burnet Muni Airport 103 76 102 76 / 10 10 0 0 Del Rio Intl Airport 104 78 104 77 / 0 0 0 0 Georgetown Muni Airport 104 78 103 79 / 10 10 0 0 Hondo Muni Airport 102 73 102 74 / 0 0 0 0 San Marcos Muni Airport 103 75 103 76 / 10 10 0 0 La Grange - Fayette Regional 104 76 103 77 / 10 10 0 0 San Antonio Intl Airport 103 77 102 77 / 0 0 0 0 Stinson Muni Airport 104 76 104 76 / 0 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 7 PM CDT Sunday for TXZ171>173-191>194- 205>209-220>225.