Texas Severe Extreme Heat Warning | Effective 06/17/2026 13:42

Headline: 
Extreme Heat Warning issued June 17 at 3:42PM CDT until June 18 at 8:00PM CDT by NWS Austin/San Antonio TX
Event: 
Extreme Heat Warning
Urgency: 
Expected
Effective: 
June 17, 2026 - 1:42pm
Expires: 
June 18, 2026 - 5:00am
Description: 
* WHAT...Dangerously hot conditions with heat index values up to 115 expected. * WHERE...The I-35 corridor, Coastal Plains, and southern Rio Grande Plains. * WHEN...From noon to 8 PM CDT Thursday. * IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events. * ADDITIONAL DETAILS...Conditions Thursday will be more extreme than the heat so far this summer. The risk of heat related illnesses will be higher with little time to adjust to the extreme heat.
Instruction: 
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Do not leave young children or pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1.
Area Description: 
Williamson; Hays; Travis; Bastrop; Lee; Uvalde; Medina; Bexar; Comal; Guadalupe; Caldwell; Fayette; Maverick; Zavala; Frio; Atascosa; Wilson; Karnes; Gonzales; De Witt; Lavaca; Dimmit
Forcast Office: 
NWS Austin/San Antonio TX