San Antonio, Texas – Brutal heat will grip San Antonio on Monday, May 19, with a dangerous heat index peaking near 106°F during the afternoon. Drivers on I-35 and Loop 410 should expect haze in the morning and rising temperatures through mid-day, followed by a chance of isolated storms Monday night.
According to the National Weather Service, south winds of 10 to 15 mph will push humid Gulf air across Bexar County, spiking heat index values across the metro. Highs will top out around 99°F, making it one of the hottest days of the Spring so far. The agency warns that outdoor activity should be limited between noon and 6 p.m., and residents should stay hydrated, seek shade, and never leave children or pets in vehicles.
Monday night brings a 20% chance of isolated thunderstorms across the region. Storms are more likely near higher terrain or eastern Bexar County. Winds may gust to 25 mph. No widespread severe weather is expected, but lightning and brief heavy rain are possible.
Looking ahead, Tuesday offers a reprieve, with sunny skies and a high near 93°F, followed by mild overnight lows around 74°F. The pattern holds through midweek with highs in the low-to-mid 90s, but humidity stays elevated.
🔍 5-Day San Antonio Forecast:
- Monday: Hot, 99°F. Heat index 106°F. PM storm chance.
- Tuesday: Sunny, 93°F. Light north breeze.
- Wednesday: Partly sunny, 96°F.
- Thursday: PM storms possible. High 94°F.
- Friday: Sunny, 94°F.
