San Antonio, Texas – Relentless late September heat will grip San Antonio early this week, with highs soaring to 98°F by Tuesday and only slight relief in sight. Residents should prepare now for dangerous heat index values near 100°F and stay alert as isolated thunderstorms roll in by Tuesday evening.
According to the National Weather Service, Monday and Tuesday will bring peak heat, with mostly sunny skies and persistent highs in the upper 90s. Southeast winds of 5 to 10 mph will offer little cooling. The region may see the first signs of change Tuesday afternoon, when a 20% chance of thunderstorms develops—bringing a brief drop in temps but an uptick in local road hazards.
Localized rainfall could impact travel along I-35 and Loop 410, especially during the evening commute Tuesday. While storms are not widespread, the mix of high temps and scattered downpours may reduce visibility and create slick roads. The risk continues through Wednesday, with another 40% chance of showers and thunderstorms after 1 p.m.
Avoid strenuous outdoor activity during peak hours Monday and Tuesday, and check on vulnerable individuals. Stay hydrated and keep emergency kits stocked in case of power outages during potential storms.
The second half of the week brings modest cooling, with highs returning to the low 90s by Friday under mostly sunny skies.
Five Day Forecast for San Antonio, TX:
- Monday: Mostly sunny, high of 97°F.
- Tuesday: High of 98°F, slight chance of storms by afternoon.
- Wednesday: Showers possible, high near 95°F.
- Thursday: Mostly sunny, slight chance of storms, high of 93°F.
- Friday: Mostly sunny and dry, high near 93°F.
