textproduct: Austin/San Antonio

KEY MESSAGES

Updated at 124 PM CDT Sun Oct 25 2026

- Mild to warm conditions continue through the week.

- Periodic rain chances return early in the week with the highest chances Thursday and Friday for the southern Edwards Plateau and Rio Grande Plains (65 to 85% for those areas).

SHORT TERM

(Tonight through Monday night) Issued at 124 PM CDT Sun Oct 25 2026

An expansive plume of cirrus is spreading north across the region this afternoon as upper-level moisture sheared off from Hurricane Vance in the eastern Pacific rides the corridor between an upper ridge to our east and the upper trough to our west. The more favorable synoptic forcing for ascent is displaced to our west and relatively stable air at 0-3 km is still being transported from the east, so the impact of this moisture will largely be limited to clouds slightly reducing daytime temperatures. A shortwave trough traverses the Edwards Plateau Monday, but there won't be much deep- layer moisture to work with ahead of that trough. A few of the hi- res models including the HRRR and HRWs develop a batch of showers over Mexico that moves across the southern Edwards Plateau Monday afternoon, but a lack of instability should keep their intensity low. Slightly higher low-level moisture from southeasterly flow along the Rio Grande may produce an occasional stray shower within the Coastal Plains to Rio Grande Plains through Monday afternoon, but most other areas should stay dry.

Highs today and Monday are forecast to reach the upper 70s to mid 80s for most of the region. Temperatures tonight will be cooler as dry low-level air moves over the area, most noticeably for those north of Interstate 10. High clouds will dampen the radiational cooling somewhat, but rural portions of the Austin area and Hill Country should dip into the mid 50s, with upper 50s to mid 60s elsewhere. A late-arriving increase in Gulf moisture arrives Monday night, which should restore milder conditions Monday night into Tuesday morning.

LONG TERM

(Tuesday through next Sunday) Issued at 124 PM CDT Sun Oct 25 2026

Midweek moisture will be more plentiful as southerly flow responds to broad diffluence over the Rockies and Plains. While there isn't a distinct disturbance to take advantage of this moisture Tuesday and Wednesday, the moist onshore flow and neutrally stable environment afforded by the broad longwave troughing over the western US suggest opportunities for scattered light to moderate showers and a few isolated thunderstorms Tuesday and Wednesday emanating from the coastal bend. Low to medium chances for rain extend from the Coastal Plains through the I-35 corridor towards the Hill Country, with the best chances (40-50%) south of the San Antonio area Tuesday afternoon, shifting eastward to the Highway 77 corridor on Wednesday as weak shortwave ridging moves over the area. Regional rain amounts should generally be in the range of a few tenths from this activity, though an isolated spot could forseeably pick up an inch from a heavier shower or storm.

Better rain chances arrive later in the week as a broad trough arriving over the Baja California on Thursday results in more meridional flow in the subtropical jet. This pattern is well timed to siphon off additional moisture and energy from Hurricane Vance, which is forecast to decay off the Pacific Mexican coast later this week. Modeled PWATs from the long range ensembles are clustered around 1.6 to 1.9 inches, or above the 90th percentile for late October. This moisture will provide an opportunity for scattered to widespread rain with some directly associated with the moisture plume and diffluence aloft and others moving inland as feeder showers and storms from the coast. The latest models have shown a focus for rainfall (both in likelihood and magnitude) mainly stretching from the Rio Grande Plains northward to the southern Edwards Plateau, aligned with the strongest vapor transport and potentially limited on its eastern extent by somewhat more stable conditions accompanying the surface high pressure over the Eastern US. Rain chances increase Thursday as the moisture arrives, and there is good consensus that the rain intensity peaks Thursday night through Friday morning as a 30 kt low-level jet ramps up along the Rio Grande, likely becoming slightly more diffuse and shifting north and east Friday afternoon. The peak rain chances are highest (65- 85%) along the Rio Grande and southern Edwards Plateau, including the Del Rio area, and decrease eastward (to about 20-40%) towards the Coastal Plains. There has been a recent uptick in mean ensemble forecast rain amounts along the Rio Grande and southern Edwards Plateau in recent runs, consistent with the focusing of moisture over those areas. While the 15-25 kt deep-layer flow should keep individual showers moving at a steady clip, the long channel of moisture and high PWAT values indicate opportunities for recurring and at times heavy rain. The latest ECMWF EFI guidance suggests a potential for locally heavier amounts over the southern Edwards Plateau and along the Rio Grande. Thus, we'll be keeping an eye on a potential isolated flood risk mainly late Thursday into Friday morning. At present, the main risk area is west of the I-35 corridor, extending to the Rio Grande.

The bulk of the tropical Pacific moisture plume should cycle past our area by Saturday. A weak shortwave trough may reinvigorate showers north of I-10 on Saturday for a final round of wet weather, but rain chances generally decrease through the weekend. Skies clear some as the shortwave pattern becomes slightly anticyclonic, but the continued presence of southwesterly flow aloft will probably keep cirrus streaming over the area.

Daytime high temperatures throughout the week are expected to hover in the mid 70s to mid 80s, varying with cloud cover and rain. Thursday and Friday could trend cooler over the southern Edwards Plateau and Rio Grande if the rain signal continues to be concentrated there. Overnight temperatures remain steadily in the 60s, slightly above seasonal normals.

AVIATION

(18Z TAFS) Issued at 124 PM CDT Sun Oct 25 2026

All terminals are VFR with mid and high level clouds covering South- Central Texas. These conditions will continue through the afternoon and evening. Winds will be near 10 kts from the east to southeast. The Austin and San Antonio airports will remain VFR through night and Monday morning. MVFR ceilings will return to DRT Monday morning and last through the end of the period.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 58 83 63 82 / 0 0 10 20 Austin Bergstrom Intl Airport 55 84 62 82 / 0 0 10 20 New Braunfels Muni Airport 58 83 63 82 / 0 0 10 40 Burnet Muni Airport 57 79 61 78 / 0 0 0 10 Del Rio Intl Airport 65 80 64 83 / 10 30 10 10 Georgetown Muni Airport 56 82 61 81 / 0 0 0 20 Hondo Muni Airport 60 82 64 82 / 0 0 10 50 San Marcos Muni Airport 55 84 62 82 / 0 0 10 30 La Grange - Fayette Regional 55 85 63 82 / 0 0 10 40 San Antonio Intl Airport 59 82 65 81 / 0 0 10 50 Stinson Muni Airport 61 83 66 82 / 0 0 10 50

EWX WATCHES/WARNINGS/ADVISORIES

None.