Martinez Lake, Arizona, reached a record-breaking 112 degrees Fahrenheit on Friday, March 20, 2026, tying a national record for the highest March temperature in the United States, according to data released Saturday. The reading, recorded at a station outside Yuma, followed a record of 110 degrees at the same location the previous day, March 19.
The unprecedented heat extended across the border into California, with stations near Ogilby and Winterhaven also registering 112 degrees on March 20. These temperatures surpassed the previous record of 108 degrees set on March 18 in Thermal, California.
The National Weather Service (NWS) attributed the extreme temperatures to a high-pressure system positioned over the Grand Canyon State, creating “an expansive dome of unusually hot temperatures.” The heat wave has affected all of Arizona and much of the American Southwest, with Yuma and Phoenix experiencing some of the highest readings.
Phoenix also experienced record-breaking heat, reaching 100 degrees on March 18 – the earliest date the city has ever hit that mark. The following day, temperatures climbed to 105 degrees, exceeding the daily record by nearly 10 degrees. The NWS noted that the typical first 105-degree day in Phoenix occurs around May 22.
Authorities have issued extreme heat warnings for 13 counties across Arizona, advising residents and visitors of the increased risk of heat-related illnesses. The heat wave coincided with the ongoing spring training season, prompting officials to advise those spending time outdoors to capture precautions, including applying sunscreen, wearing lightweight clothing, and seeking shade.
The city of Phoenix announced the closure of several hiking trails from 8 a.m. To 5 p.m. From March 19 through March 22 due to the dangerous conditions. Residents in necessitate of cooling centers were directed to call 211 for assistance.
Whereas the NWS indicated that this week’s heat spike does not necessarily foreshadow a deadly summer, citing the potential influence of the El Niño climate pattern, scientists have also pointed to long-term aridification trends in the American West. Warming temperatures are increasing evaporation, reducing the amount of usable water available from precipitation.
The extreme heat is expected to continue through the weekend, with Phoenix forecast to experience highs exceeding 100 degrees through March 24. The Phoenix Sky Harbor International Airport has a 75% chance of reaching 105 degrees or higher on March 20 and 21, potentially breaking previous records by nearly 10 degrees.
Martinez Lake, located approximately 60 miles north of Yuma on the Lower Colorado River, is a popular destination for fishing and water sports, according to the Arizona Game and Fish Department. Fish species in the lake include largemouth bass, smallmouth bass, striped bass, crappie, and various catfish.