The highest heat index on record occurred Tuesday in San Antonio🥵

Heat index records began in the 1940s in San Antonio

The hottest heat index on record for San Antonio was calculated on June 20, 2023 (Copyright 2023 by KSAT - All rights reserved.)

No doubt about it -- the heat and humidity have been in full force this June!

Afternoon dewpoints in the mid-upper 70s occurred in San Antonio Thursday (6/15), Friday (6/16), and Tuesday (6/20) making feels-like temperatures soar well into the triple digits across the majority of South Central Texas.

Here in San Antonio, the peak heat index value managed to climb to 113 degrees Thursday (6/15), which made for a record. Thursday’s record lasted for a measly 24 hours when the very next day, Friday (6/16), the record was broken again with a heat index of 115 degrees.

To make things even more toasty, the record was yet again broken on Tuesday (6/20)! A peak heat index of 116 degrees has now been calculated at San Antonio International Airport, snagging the top spot for the hottest heat index value on record.


Looking ahead, it’ll stay hot and humid through at least the last week of June. Stay hydrated, wear sunscreen, and take care of the pets! We’ll keep you posted.

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About the Authors:

Meteorologist Mia Montgomery joined the KSAT Weather Authority Team in September 2022. As a Floresville native, Mia grew up in the San Antonio area and always knew that she wanted to return home. She previously worked as a meteorologist at KBTX in Bryan-College Station and is a fourth-generation Aggie.

Sarah Spivey is a San Antonio native who grew up watching KSAT. She has been a proud member of the KSAT Weather Authority Team since 2017. Sarah is a Clark High School and Texas A&M University graduate. She previously worked at KTEN News. When Sarah is not busy forecasting, she enjoys hanging out with her husband and cat, and playing music.