NORTH SHORE, Calif. (AP) — A day after a tiny desert community in Southern California reached 108 degrees (42.2 Celsius), tying the highest March temperature ever recorded in the U.S., forecasters warned Thursday that record-breaking winter heat across the Southwest will continue into the weekend.

North Shore, California, on Wednesday tied a mark first set at Rio Grande City, Texas, in 1954. The aptly named town of Thermal, also in the California desert northeast of San Diego, was forecast to hit 110 (43.3 C) degrees on Friday.

There was little relief after the sun went down. In Arizona, Phoenix set a record-high overnight low temperature for March 19 of 69 (20.5 C) degrees, according to the National Weather Service. Daytime highs will top out at around 105 (40.5 C) degrees on Thursday, and it could be even hotter on Friday. “For some perspective, the average first 105 degree day of the year normally occurs on May 22nd,” the weather service said in a statement. The last time Phoenix temperatures climbed into the hundreds during March was almost 40 years ago.

Several cities on Wednesday experienced their hottest March day in four decades, according to the weather service.

Las Vegas hit 99 (37.2 C) degrees, smashing its March record, which was 93 (33.8 C) degrees in 2022.

Downtown Los Angeles reached 94 (34.4 C) degrees, beating its previous daily high of 87 (30.5) degrees in 1997.

And the desert destination of Palm Springs, California, was 104 (40 C) degrees, tying its hottest March day on record from 1966.

It will continue to be 20 to 30 degrees above normal March temperatures for the rest of the week in the Southwest before the mercury drops slightly starting Sunday. Many other cities in the region are expected to see their earliest 100-plus (37.8-plus C) degree day on record, according to the weather service.

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