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Arizona community sets new US March heat milestone
A remote desert settlement near Martinez Lake in Arizona registered 43°C (110°F) on Thursday, surpassing the previous national March high-temperature record, the National Weather Service confirmed.
Heatwave engulfs US Southwest
The exceptional warmth arrived during the final days of winter, blanketing California, Arizona, and Nevada. The previous March record-42°C (108°F)-had stood since 1964 in Rio Grande, Texas.
Multiple cities matched or exceeded earlier benchmarks this week. A town close to North Shore, California, equaled the 42°C mark on March 18, while Phoenix logged its hottest March day ever at 40°C (105°F), topping Wednesday's 39°C (102°F) record. Las Vegas also broke its previous high, reaching 35°C (95°F) on Wednesday.
Meteorologists warn of risks
Forecasters at the Las Vegas NWS office cautioned that the combination of extreme early-season heat and elevated tourism posed serious health threats. Typically, the first 40°C (105°F) day in Phoenix does not occur until late May.
"Extreme early-season heat coupled with high tourism rates will make this heat very dangerous," the Las Vegas NWS office stated earlier this week.
Climate patterns behind the surge
The intense conditions stemmed from a slow-moving high-pressure system, often referred to as a heat dome, which trapped hot air over the region. Temperatures soared 11-17°C (20-30°F) above seasonal averages.
Scientists link the increasing frequency, intensity, and duration of heatwaves to human-driven climate change. Global temperatures have already risen approximately 1.1°C since the industrial era began, and further warming is projected unless governments implement significant emissions reductions.
Outlook
While the immediate heatwave is expected to ease, long-term forecasts suggest above-normal temperatures will persist across the Southwest in the coming weeks.
