textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 1204 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

(06Z TAFS) Issued at 1204 AM CDT Sat Aug 22 2026

VFR flight conditions prevail through the period. Few patchy low clouds are possible this morning and again Sunday morning but flight impacts at the area terminals are not anticipated. There will be some high clouds arriving later today and could continue to pass through the region at times into Sunday. This afternoon features a slight chance for shower or storm across northern portions of the region. KAUS could possibly see something approach but confidence remains too low to insert any mention in the TAFs at this time. Winds generally remain around 10 kt or less through the period, with the highest speeds just after sunset with the sea breeze.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 105 80 104 79 / 20 10 10 0 Austin Bergstrom Intl Airport 104 79 103 78 / 20 10 10 0 New Braunfels Muni Airport 102 77 103 76 / 10 0 10 0 Burnet Muni Airport 102 77 102 76 / 20 10 10 0 Del Rio Intl Airport 104 78 104 77 / 0 0 0 0 Georgetown Muni Airport 103 80 103 79 / 20 10 10 0 Hondo Muni Airport 101 75 102 74 / 0 0 0 0 San Marcos Muni Airport 103 77 102 76 / 10 10 10 0 La Grange - Fayette Regional 103 78 103 77 / 20 10 10 0 San Antonio Intl Airport 102 78 102 77 / 0 0 0 0 Stinson Muni Airport 103 77 103 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.