textproduct: Austin/San Antonio

KEY MESSAGES

- Low chance for a few showers and storms through Monday.

- Active weather pattern from mid-week through the upcoming Memorial Holiday weekend. Heavy rain at times could lead to localized flooding.

SHORT TERM

(Tonight through Monday night) Issued at 118 PM CDT Sun May 17 2026

Cloud cover from this morning remains fairly thick across the region as we head into the early afternoon hours. We are seeing some partial clearing from time to time, especially out west over the Rio Grande plains. A few radar returns are noted and given the partial clearing, daytime heating as well as some support from the hi-res models, we have kept a low chance for showers and thunderstorms through the early evening hours. Widespread low clouds and south winds will keep a warm and humid air mass intact tonight into Monday as an active southwest flow aloft persists. Rain chances from the NBM appear too low today into Monday and we have opted to add a low chance (20-30%) to most of the region. The afternoon and evening hours appear most favorable for some isolated shower and thunderstorm development. Daytime highs will be at or a few degrees above normal, with overnight lows running some 10 degrees above normal.

LONG TERM

(Tuesday through next Sunday) Issued at 118 PM CDT Sun May 17 2026

The pattern is expected to become a little more active as we head into the middle of the week. A weak cold front approaches from the north late Tuesday evening into early Wednesday morning as a fairly stout shortwave trough embedded in the southwest flow aloft moves across the region. Rain chances will go up considerably in this pattern and given the amount of moisture in the atmosphere, efficient rain producing convection is expected. WPC maintains a level 2 of 4 risk for heavy rainfall generally north of Highway 90, with a level 1 of 4 risk elsewhere. The above mentioned boundary weakens considerably as we head into Thursday and Friday, but the medium range guidance suggests another round of shortwave energy moving in from the southwest. Rain chances remain high given the pattern, with convection likely favored during the peak heating hours both days.

Southwest flow aloft persists into the upcoming Memorial Day weekend and rain chances will remain in the forecast. It will be tough to determine which days remain favored for rainfall as it will be difficult to time the periods of favorable lift moving into the region. Persistent clouds and rain chances will likely keep temperatures below normal through the mentioned period.

AVIATION

(18Z TAFS) Issued at 1238 PM CDT Sun May 17 2026

MVFR CIGs are gradually improving to VFR regionwide as continued south/southeast winds of 10-18 kt mix out the low clouds. Some small -SHRA is noted on radar near KAUS and KSAT and should continue to 00Z, though this has been kept out of the TAFs due to most likely placement west of the I-35 sites. Another round of MVFR CIGs should return after 04Z tonight and eventually expand across the entire region before lifting tomorrow afternoon. Smoke transport modeling suggests a period of HZ with slightly reduced 4-5 SM VSBYs is possible at I-35 sites between 06Z-12Z, but will need to evaluate in later cycles before adding to TAFs. Breezy prevailing flow is expected to continue through tomorrow.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 78 92 78 91 / 20 20 20 50 Austin Bergstrom Intl Airport 79 92 79 91 / 20 20 20 50 New Braunfels Muni Airport 77 92 77 91 / 20 10 20 40 Burnet Muni Airport 75 88 75 87 / 20 10 20 50 Del Rio Intl Airport 77 97 77 95 / 20 10 20 20 Georgetown Muni Airport 77 90 77 89 / 20 20 20 50 Hondo Muni Airport 77 91 77 90 / 20 10 20 30 San Marcos Muni Airport 78 92 79 91 / 20 10 20 50 La Grange - Fayette Regional 79 91 79 90 / 20 10 20 40 San Antonio Intl Airport 78 92 78 91 / 20 10 20 40 Stinson Muni Airport 78 93 78 92 / 20 10 20 30

EWX WATCHES/WARNINGS/ADVISORIES

None.