More than 60 million people are being warned of sweltering temperatures Saturday as an early-season heat wave hits a swath of thSouthern U.S. from California to Arkansas.

On Saturday, National Weather Service stations in Phoenix, Houston, Albuquerque and San Antonio warned of extreme heat exceeding 110 degrees in some areas. Nearly all of Texas, Oklahoma and Arkansas are under a heat advisory, the National Weather Service reports.

On Friday, Phoenix and Las Vegas reported record daily highs, according to the National Weather Service. Arizona’s capital city  reached 113 degrees, surpassing  its previous record of 111 set in 1978. Las Vegas hit 109, breaking the previous record, set in 1996, by 1 degree. 

And, in New Mexico, Albuquerque reached 100 degrees for the first time this year.

“It’s really the first big heat wave of the season,” NWS forecaster Bryan Jackson told USA TODAY on Friday. “It catches people off-guard.”

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