Martinez Lake Hits 110 Degrees, Setting U.S. March Temperature Record

A desert community in southwestern Arizona hit 110 degrees on Thursday, setting a new record for the hottest March temperature ever recorded in the United States. The reading came from a weather station just outside Martinez Lake, a recreation community about 45 minutes north of Yuma and roughly 145 miles west of Phoenix, sitting near the Arizona-California border in the Yuma Desert.

The previous national March temperature record stood at 108 degrees Fahrenheit, first set in Rio Grande City, Texas, in 1954, and had endured for nearly seven decades before being tied earlier in the week by North Shore, California. Martinez Lake's 110-degree reading surpassed that 72-year-old benchmark by two full degrees.

The record did not arrive without warning. The reading was recorded just outside Martinez Lake in the Yuma Desert as a winter heat wave scorched the Southwest, according to the National Weather Service. The National Weather Service and NOAA's Weather Prediction Center had flagged the cause as early as March 16, describing a high-pressure system spinning across the West and producing what forecasters called "an expansive dome of unusually hot temperatures." The NWS characterized the resulting temperatures as "unprecedented."

Martinez Lake hit 110 degrees on March 19, breaking a national March heat record as a heat wave swept the Southwest. Phoenix, 145 miles to the east, reached 105 degrees the same day, breaking the previous record of 97 for that calendar date set in 2017, according to the Arizona Republic. The NWS noted Phoenix's high was around 25 degrees above normal. For scale, the NWS posted on X that "the average first 105-degree day of the year, on average, normally occurs on May 22nd," meaning this week's heat arrived roughly two months ahead of schedule. An extreme heat warning covered metro Phoenix.

The heat wave hit the entire Southwest, setting records from Phoenix to Las Vegas, Los Angeles, and San Francisco. Las Vegas reached 95 degrees, topping its previous March record. The BBC reported that records for earlier-than-usual high temperatures were broken in multiple states, including California, Arizona, and Nevada.

In Thermal, California, a worker named Ruben Pantaleon kept cleaning car windshields at an intersection Thursday afternoon, shorts on, a supply of electrolyte drinks at his side. "I drank three of those so far," he said. "It's the desert. It gets real hot. I'm not worried about it." Camelback Mountain in Phoenix closed its trails to hikers that day because of the extreme heat.

NWS meteorologist Bryan Lewis noted: "We've broken so many records yesterday and even today we've broken quite a few so far."

The Las Vegas NWS office warned that "extreme early-season heat coupled with high tourism rates will make this heat very dangerous." Scientists and meteorologists have placed events like this in a broader pattern: the BBC reported that heatwaves have become more frequent, more intense, and longer-lasting because of human-induced climate change, and that global temperatures will keep rising without steep cuts to emissions.

The temperature reached 110 degrees near Martinez Lake, the hottest ever recorded in the U.S. during the month of March. For La Paz County, that is not an abstraction. Martinez Lake is a community where people fish, camp, and launch onto the Colorado River. A temperature that would be extreme in mid-July arrived on a March Thursday, rewriting a record that had stood since the Eisenhower administration.