San Antonio residents will sweat through dangerous heat Thursday before storm chances rise heading into Labor Day weekend. The National Weather Service warns that heat index values could climb as high as 103, creating hazardous conditions for outdoor workers and drivers. Those traveling on I-35 and Loop 1604 should prepare for delays if late-week storms bring heavy rain and lightning.
According to the National Weather Service, Thursday will be mostly sunny with highs near 99 degrees. South winds around 10 mph will offer little relief. By Friday, heat intensifies with highs reaching 100, while humidity keeps real-feel temperatures above triple digits. Emergency managers urge residents to limit afternoon activity, hydrate often, and check on vulnerable neighbors.
Storm chances return late Saturday into Sunday. A 20 percent chance of showers and thunderstorms could expand overnight, potentially impacting outdoor events and holiday travel. While widespread flooding is not expected, localized downpours could slow traffic and create slick roadways across Bexar County.
Labor Day itself looks slightly cooler, with highs near 92 and scattered showers possible by late afternoon. Those planning backyard gatherings or road trips should monitor updates as storm chances rise into Tuesday.
Heat remains the immediate concern. Cooling centers across San Antonio remain open, and CPS Energy reminds residents to conserve electricity during peak afternoon hours.
Warnings remain in effect through Friday evening, with additional advisories possible as storms approach.
Five-Day Forecast for San Antonio, Texas
- Thursday: Mostly sunny, high near 99. Heat index 103.
- Friday: Sunny, hot, high 100.
- Saturday: Mostly sunny, high 98. Evening storms possible.
- Sunday: Partly sunny, scattered storms, high 90.
- Labor Day Monday: Mostly sunny, storm chance late, high 92.
