San Antonio is waking up to mostly cloudy skies and muggy air Monday, with temperatures around the mid-70s early and a high near 93. The heat index could reach 102, making the afternoon feel more like midsummer than mid-October.
Skies should turn partly sunny through the day, while a south-southeast breeze runs 5 to 10 mph and could gust to 20 mph. A slight chance of rain showers arrives after 4 p.m., but the chance of measurable rain remains just 20%.
Tuesday Brings Even More Heat
Monday night stays warm and humid, with a low near 77 and a small chance of showers before 7 p.m. Tuesday looks hotter, with a high near 95 and heat index values as high as 105 under partly sunny skies.
Wednesday brings another hot afternoon near 93, along with a slight chance of showers and thunderstorms after 1 p.m. Rain chances remain limited around San Antonio, though storms could become more common east of the Interstate 35 corridor.
Cold Front Finally Breaks The Heat
The pattern changes late in the week as a cold front moves through the region. Thursday should still reach about 91, but Friday drops to a much more manageable high near 81 with north-northeast winds around 20 mph and gusts up to 40 mph.
The cooler stretch continues into the weekend, with highs near 75 Saturday and 78 Sunday. Overnight lows could fall to 58 Saturday night, a dramatic turn from the muggy upper 70s expected through Wednesday.
Understanding Humid-Heat Risk
The National Weather Service Weather-Ready Nation program explains that the heat index describes how hot conditions feel when humidity is factored in. That puts Monday’s forecast heat index of up to 102 and Tuesday’s value of up to 105 in context: the air temperature alone does not convey how hot it may feel. During the hottest parts of those days, residents should limit strenuous outdoor activity and drink plenty of water.
No watches, warnings or advisories are listed for the San Antonio area.
