Martinez Lake Hits 110 Degrees, Setting All-Time U.S. March Heat Record

A small, unincorporated community in the Yuma Desert just made weather history. Martinez Lake, situated along the Colorado River about 145 miles west of Phoenix, recorded 110 degrees Thursday, breaking the highest March temperature ever documented in the United States, according to the National Weather Service.

The previous record of 108 degrees had stood since 1954, when Rio Grande City, Texas, first logged it. That mark lasted 71 years before North Shore, California, tied it Wednesday. Martinez Lake snapped it the very next day.

The reading arrived on the last day of winter, during a heat wave that has rewritten record books across the Southwest. The National Weather Service put the anomaly in stark terms: "For some perspective, the average first 105-degree day of the year normally occurs on May 22nd."

Thursday's 110-degree peak was not limited to Yuma County's corner of the desert. Cathedral City, near Palm Springs, and the aptly named Thermal, northeast of San Diego, each hit 108 degrees by Thursday afternoon. Thermal was forecast to approach 110 on Friday and could tie the newly set March record.

Phoenix also logged its earliest triple-digit reading ever, hitting 101 degrees Wednesday, breaking a mark set nearly 40 years ago on March 26, 1988. Across the region, Las Vegas reached 99 degrees, obliterating its previous March 18 daily record of 93 degrees set in 2022, while downtown Los Angeles hit 94 degrees, topping its 1997 benchmark of 87 degrees for the same calendar date. The blistering wave established record highs in dozens of locations, including San Diego, Los Angeles, Las Vegas, and San Francisco, the National Weather Service confirmed.

In Thermal, Ruben Pantaleon worked through it, using a squeegee to clean car windshields at an intersection Thursday afternoon. He wore shorts and kept a supply of electrolyte drinks within reach. "I drank three of those so far," he said. "It's the desert. It gets real hot. I'm not worried about it."

Not everyone had that option. Camelback Mountain, the Phoenix-area landmark, posted signs closing its trails due to extreme heat, with digital displays reading "TRAILS CLOSED EXTREME HEAT WARNING." Forecasters warned the heat would continue into the weekend, with heat warnings expected through Sunday.