Weather Alerts For San Marcos, TX

# HEADLINE -------------------- HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT WEDNESDAY # DETAILS -------------------- WHAT Temperatures up to 105 and heat index values up to 110 expected Tuesday and Wednesday. WHERE Atascosa, Bexar, Comal, De Witt, Guadalupe, Hays, Karnes, and Wilson Counties. WHEN Until 7 PM CDT Wednesday. IMPACTS Hot temperatures and high humidity may cause heat illnesses. ISSUED AT Tuesday, August 25, 2026 at 3:02 PM CDT ISSUED BY National Weather Service Austin/San Antonio TX HEADER URGENT - WEATHER MESSAGE # PRECAUTIONARY/PREPAREDNESS ACTIONS -------------------- Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke. 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. # AREAS AFFECTED -------------------- Atascosa, Bexar, Comal, De Witt, Guadalupe, Hays, Karnes, Wilson Including the cities of Seguin, San Antonio, Cuero, Pleasanton, Floresville, Karnes City, New Braunfels, and San Marcos