textproduct: Austin/San Antonio

KEY MESSAGES

- Showery weather with some thunderstorms along and east of I-35 continuing through the evening before lessening tonight.

- Hot and humid weather this weekend with heat indices near or exceeding 100F.

SHORT TERM

(Tonight through Thursday night) Issued at 126 PM CDT Wed Apr 22 2026

Our anomalously cool airmass has fully eroded, with warm and moist Gulf air now firmly situated over South-Central Texas. Daytime heating has already enabled the development of a few showers along the US77 corridor. Hi-res models remain in decent agreement in showing continued clusters of isolated to scattered showers and some thunderstorms this afternoon and evening, mainly over the Coastal Plains but potentially scooting closer to the I-35 corridor with time. While the atmosphere is not nearly as saturated as on previous days, slow storm motions under 15 mph against the low-level flow could produce some locally higher rain amounts through the evening if storms become more vertically established (with potential for a highly localized max of up to about 4 inches). Higher chances of this are over the Coastal Plains, where some isolated and localized flooding (mainly in cities and towns) could occur if a storm persists. Severe weather is unlikely, but high conditional instability and modest wind shear could briefly support a few stronger storms capable of small hail and gusty winds.

Another round of patchy to areal fog is anticipated Thursday morning, though slightly stronger winds should limit the extent and mainly favor areas along the Balcones Escarpment. A lobe of warm mid- level air and a weak ridge aloft moving over the area Thursday should allow for a drier day with highs mostly in the mid 80s, along with a few spots in the Rio Grande Plains breaching into the 90s.

LONG TERM

(Friday through next Wednesday) Issued at 126 PM CDT Wed Apr 22 2026

Zonal flow aloft favors warm and generally rain-free conditions to end the week. Highs are expected to warm into the 90s this weekend into next week. Hot and humid afternoons with dew points above the 90th percentile are forecast starting Friday and continuing through the weekend. This combination could push heat indices near and over 100F, especially considering the additional moisture input from our preceding rains. It could be quite a quick shift from our days of cooler weather.

While an active synoptic pattern kicks off over the Southwestern US, the main storm track favors areas to our north, and ensemble means have kept mostly quiet regarding rain chances in our area as capping will likely remain strong. Some diurnally driven dry line action is possible, which could produce a low probability conditional risk for some heavier downpours or severe weather. A slight upward trend in cloudiness is anticipated heading into next week as a stationary front to baroclinic trough becomes draped nearby. Rain chances are low at this time, but would be dependent on whether any small perturbations in the flow aloft become well-timed to intersect this front. The current blend of models keeps rain chances below 20 percent through the weekend into early next week.

Troughing generally persists over the western US through the forecast period. Eventually, southwest upper-level low could increase over our area by midweek next week, perhaps setting up another possible period for good rains beyond the forecast window.

AVIATION

(06Z TAFS) Issued at 1212 AM CDT Thu Apr 23 2026

Low clouds are developing and should spread across the terminals within the next hour or two. Initially ceilings will be MVFR and then drop to IFR later tonight. LIFR conditions are likely in the San Antonio area close to sunrise. Expect gradual improvement until VFR conditions return by mid-afternoon. Low ceilings will redevelop late tonight.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 85 70 88 70 / 0 10 20 10 Austin Bergstrom Intl Airport 85 70 87 70 / 0 10 20 10 New Braunfels Muni Airport 85 69 87 69 / 0 10 20 10 Burnet Muni Airport 82 69 88 68 / 0 10 10 10 Del Rio Intl Airport 88 70 93 70 / 10 10 0 0 Georgetown Muni Airport 83 69 88 69 / 0 10 10 10 Hondo Muni Airport 84 69 86 68 / 0 10 10 0 San Marcos Muni Airport 85 69 87 69 / 0 10 20 10 La Grange - Fayette Regional 85 70 87 70 / 0 0 20 10 San Antonio Intl Airport 85 70 87 70 / 0 10 20 0 Stinson Muni Airport 86 71 87 71 / 0 10 20 0

EWX WATCHES/WARNINGS/ADVISORIES

None.