San Antonio rolled into Saturday, June 13, 2026, under a blanket of clouds and thick, sticky air, with temperatures already in the mid to upper 70s and the humidity making it feel warmer. Afternoon highs are expected to climb to around 91°F, with heat index readings pushing into the low 100s. A slight chance of scattered showers and isolated thunderstorms kicks in after 1 p.m., and south-southeast winds should run 5 to 10 mph with gusts near 20 mph. If you have outdoor plans, it is a good idea to move the hard stuff to early morning or later in the evening and bring plenty of water.
Afternoon Storms Possible
Forecasters at the National Weather Service say the hit-or-miss shower setup sticks around through Sunday, with coverage bumping up and the best odds for storms Sunday afternoon into Monday. Sunday, June 14, is expected to top out near 91°F, with about a 50% chance of showers and thunderstorms after 1 p.m. and heat index values possibly reaching 100 to 103°F in the muggiest neighborhoods. By Monday, June 15, an early-week front is forecast to slide in and bring more widespread showers and thunderstorms, along with the potential for locally heavy rainfall. Forecasters highlight areas along and east of I-35 as having the greatest flood concern.
Midweek Uncertainty And Flooding Risk
How soggy next week gets is still a bit of a toss-up. In one scenario, the disturbance stays parked over northern Mexico and rain chances stay more limited. In the other, the system lingers nearby and sets the stage for multiple rounds of storms that could track over the same neighborhoods. That second setup would raise the risk for flash flooding in spots if storms repeatedly redevelop over the same areas, and some locations could end up with several inches of rain from the heavier cells. If you live in a low-lying area or near creeks, it is smart to plan now to avoid driving through standing water and to make sure you have a reliable way to get severe weather alerts.
What To Do
If you are heading to an evening event, like the Confluence Park concert Saturday night, bring a lightweight rain jacket and a backup plan, since the hourly forecast keeps a small chance of showers around 7 p.m. and coverage will be spotty. For the heat, stick with the basics: drink plenty of water, take breaks in the shade or air conditioning, and check in on older neighbors or anyone who is sensitive to high temperatures. The City of San Antonio keeps hot-weather guidance and a list of cooling resources if you need a cool place during peak heat. If heavy rain shows up on Monday, steer clear of flooded roads and follow directions from local emergency officials.
Updates will be posted if any watches or warnings are issued, so check back Monday morning for the latest on the front and any flood products. Stay weather-aware and give yourself a little extra travel time if storms pop up in your area.
