San Antonio started Tuesday amid overnight Gulf moisture and pre-dawn MVFR ceilings, but those early conditions are not much of a shield. The city is headed for a sunny 100-degree afternoon, with heat index values around 106 and only a modest south-southeast breeze.
Triple-Digit Heat Takes Over By Afternoon
Temperatures should climb through the 90s after noon, reaching around 100 degrees between midafternoon and early evening. Rain is essentially a nonfactor Tuesday, with a 0% chance in the local forecast, while winds run 5 to 10 mph from the south-southeast.
The National Weather Service says parts of the broader region face a Heat Advisory from noon to 7 p.m. Tuesday, while the San Antonio point forecast lists no active local alert. The agency also flags elevated to near-critical fire-weather conditions farther west, where dry air and gusty winds could make fires spread more readily.
Little Relief After Sunset
Tonight will be mostly clear, but the low only falls to about 77 degrees, and humidity will keep it feeling warmer at times. Southeast winds of 5 to 15 mph could gust to 25 mph, so evening plans may get a breeze without getting much cooling.
Rain Chances Finally Nudge Up Thursday
Wednesday stays sunny and nearly as hot, with a high near 99 and a heat index up to 105. A slight chance of showers arrives Thursday, when the high should be around 97 and rain chances reach 20%; rain chances stay low over the weekend.
Monday could bring another slight chance of showers and thunderstorms, with a high near 94. For Tuesday, the practical move is to shift strenuous outdoor work away from the afternoon, drink water, take breaks in air conditioning or shade, and check on people and pets who are more vulnerable to heat.
