textproduct: Austin/San Antonio

KEY MESSAGES

- Line of strong to severe storms likely this evening into tonight.

- Seasonably warm temperatures and dry weather expected Monday and the rest of the week.

UPDATE

Issued at 518 PM CDT Sun May 10 2026

A Severe Thunderstorm Watch has been issued for most of South Central Texas through midnight tonight. The main severe threats are damaging wind gusts (some up to 75 mph) and large hail. Can't rule out an isolated tornado mainly across the Hill Country area. In addition, locally heavy rain is forecast with the passage of the cold front this evening and part of the overnight hours.

SHORT TERM

(Tonight through Monday night) Issued at 1225 PM CDT Sun May 10 2026

A line of strong to severe storms is expected to move northwest to southeast across most of South-Central Texas this evening into tonight. The primary severe threat posed by these storms is damaging wind, with a more isolated potential for large hail and locally heavy rain. Strong lines of storms can produce wide swaths of gusts of 50-60 mph with stronger pockets of gusts near and above 75 mph possible. Frequent lightning is also likely. The severe risk is expected to be highest when storms first enter the Hill Country and Austin area earlier in the evening, and the SPC has highlighted a Level 3 of 5 (Enhanced) risk of severe weather for these areas primarily due to the strong wind concerns. Storms should remain strong to severe as they move farther south with a continued threat for strong winds and locally heavy rain, but the severe risk is expected to gradually decline later in the night.

An upper-level shortwave trough currently diving southeast over the Rockies and an accompanying cold front will provide the lift to trigger widespread thunderstorms this evening. This front is already moving across North Texas as of early afternoon Sunday and will be encroaching upon our area soon. There is a low to medium chance of a few isolated thunderstorms developing earlier in the day (with mainly a lightning, gusty wind, and small hail threat), mainly over the Coastal Plains, in the late afternoon and early evening. The dry- line should also push slightly eastward into Val Verde County ahead of the approaching front and may itself be a trigger for some isolated thunderstorms in the late afternoon over the southern Edwards Plateau, but the cold front will produce the majority of the storm and severe activity. Most models indicate an initial arrival of storms in the Hill Country near or just after sunset, starting by about 7 PM, reaching the I-35 corridor over the following hours and moving across the Coastal Plains closer to midnight. It is worth noting that storms of this variety with conditions favoring a wind- driven line of storms can often accelerate in forward speed during their development, so it is plausible that storm arrival could be a few hours earlier than the model consensus. In general, the focus is this evening. The greatest chances for severe weather for any particular location will likely be in the first 1-2 hours of storm onset. Stay indoors and have multiple ways to receive weather information.

The highest likelihood for stormy weather and a more contiguous line of storms is generally over the Hill Country, I-35 corridor, and Coastal Plains, where the forward momentum of these storms is expected to be greatest. There is some uncertainty over the western extent of the line of storms over the Rio Grande Plains and areas west of US-83, but overall storm activity is still likely to be at least scattered in those areas with isolated severe potential. This evening's storms will likely be moving briskly, keeping regional rain totals mostly in the 0.5-1 inch range. However, a few pockets of heavier downpours could produce isolated and locally higher totals in the 2-4 inch range.

Once the main line of storms and cold front passes, residual lightning and light rain from the trailing stratiform cloud deck may continue for a few hours, but will subside with the entirety of South-Central Texas dry by sunrise on Monday. Light northerly winds throughout the day will keep temperatures in check, though temperatures should still warm into the upper 70s (with the most moderated temperatures in the Hill Country and Austin area) to mid 80s (with the warmest temperatures in the Rio Grande Plains) under mostly sunny conditions.

LONG TERM

(Tuesday through next Sunday) Issued at 1225 PM CDT Sun May 10 2026

Dry and warm weather is expected to continue for much of the week as a ridge builds overhead and maintains strength. Widespread highs in the 90s are expected by Thursday and Friday, continuing into the weekend. The last few afternoons of the week are forecast to be breezy as a tight pressure gradient sets up over the Plains. Rain chances stay near-zero for the entire work week, but some rain potential may start to reenter the picture early next week as the ridge weakens and a few upper-level disturbances start to impinge on our area within largely zonal flow.

AVIATION

(18Z TAFS) Issued at 1225 PM CDT Sun May 10 2026

VFR flight and rain free conditions are expected to continue this afternoon. Attention this evening through about 1 am then turns to the arrival and passage of a squall line of convection. Activity may be strong to severe with strong winds, hail, locally heavy rain, and frequent lightning. For KDRT, and northern areas of the Rio Grande, coverage of activity is a bit lower but would arrive earlier compared to the I-35 corridor between 00Z and 03Z. Have added a PROB30 at KDRT during that time. Across the I-35 corridor, confidence is higher for a solid line of storms with impacts in the 02Z to 06Z time frame. This will lead to prevailing groups with -TSRA for now in the KAUS, KSAT, and KSSF. The squall line is to advance east, but some lingering rain showers may persist for few hours until around 09Z. Low clouds with MVFR ceilings then filter in and will linger into Monday morning before improving to VFR levels by/into Monday afternoon. Light east to east-southeasterly winds persist ahead of the line of storms. Following the front and it's line of storms, expect a light to moderate north-northeasterly flow across the region.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 67 81 65 85 / 90 10 0 0 Austin Bergstrom Intl Airport 67 81 65 85 / 90 10 0 0 New Braunfels Muni Airport 67 82 64 85 / 90 10 0 0 Burnet Muni Airport 64 78 61 83 / 90 10 0 0 Del Rio Intl Airport 69 85 67 88 / 60 20 0 0 Georgetown Muni Airport 66 79 63 83 / 90 10 0 0 Hondo Muni Airport 67 84 64 87 / 70 20 0 0 San Marcos Muni Airport 67 82 64 85 / 90 10 0 0 La Grange - Fayette Regional 68 81 66 83 / 90 10 0 0 San Antonio Intl Airport 68 84 65 87 / 80 10 0 0 Stinson Muni Airport 68 84 66 87 / 70 10 0 0

EWX WATCHES/WARNINGS/ADVISORIES

None.