Meantime, heavy, tropical rainfall along the coast today
Any flash flooding will stay relegated to the coast today (Copyright KSAT-12 2026 – All Rights Reserved)FORECAST HIGHLIGHTS
COASTAL FLOODING: Heaviest rain stays relegated to coast, flooding possible
SPOTTY RAIN FOR SA: Isolated downpours today
VERY HOT THURSDAY: Heat index could soar above 110°
MORE RAIN CHANCES: Friday & Saturday
FORECAST
TODAY
An area of low pressure will sweep across South Texas and into the Gulf today. This low could even briefly take on tropical characteristics as it hugs the coast. However, the result is the same: flooding is possible for areas south and east of San Antonio.
In fact, because the low tightens up, rainfall will be limited for San Antonio today. Rain chances sit at just 30% for the city. The farther south and southeast you go, the higher the rain chances and flooding risk.
The highest rain chances will stay south and east of San Antonio. (Copyright KSAT-12 2026 – All Rights Reserved)
HEAT KICKS UP
In the wake of this low, stable air will fill in over the area. This will limit clouds and allow temperatures to soar. By Thursday, highs could reach the mid to upper-90s. Meantime, at the surface, we’ll still have humid conditions. That means heat index values could be near 110° on Thursday afternoon!
Temperatures will soar on Thursday, with heat index values near 110°. (Copyright KSAT-12 2026 – All Rights Reserved)
MORE RAIN CHANCES
By Friday, another front will make a run for South Texas. This could kick up more showers & storms for the area. Rain chances will continue on Saturday and some heavy rainfall will be possible. Rain chances fall again by Sunday.
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About the AuthorJustin Horne headshotJustin Horne
Justin Horne is a meteorologist and reporter for KSAT 12 News. When severe weather rolls through, Justin will hop in the KSAT 12 Storm Chaser to safely bring you the latest weather conditions from across South Texas. On top of delivering an accurate forecast, Justin often reports on one of his favorite topics: Texas history.