An unusually intense early-spring heat wave pushed temperatures to historic levels across much of the United States in March, making it the warmest March on record for dozens of cities from the West Coast to the Plains.
Preliminary data from the National Oceanic and Atmospheric Administration and the Southeast Regional Climate Center show that more than four dozen major weather stations—many with records dating back to the 1960s—set new marks for the warmest March ever recorded. Cities impacted include Dallas, San Antonio, Oklahoma City, Albuquerque, Denver, Salt Lake City, Phoenix, Las Vegas, Los Angeles and San Francisco.
Dozens of other locations also experienced near-record warmth. Cities such as Atlanta and Nashville posted their second warmest March on record, while Houston and Memphis ranked third.
Meteorologists attribute the record-breaking month largely to an 11-day heat wave in mid- to late March that sent temperatures soaring well above seasonal averages. The event set daily high-temperature records in more than 100 cities and contributed to at least 17 statewide records.
In several areas, the warmth was not just record-setting but historically extreme. Phoenix exceeded its previous warmest March by 6.5 degrees, an unusually large margin in monthly temperature records. In Las Vegas, the average temperature for March would have qualified as the city’s hottest April on record. Similar patterns were observed in parts of California, including Los Angeles, Long Beach and Santa Maria.
Climatologists note that such wide margins in monthly temperature records are rare, underscoring the severity of the heat wave. The scale and intensity of the warmth have also raised questions about how March 2026 compares nationally to past extremes.
While official national rankings will be released by NOAA in its monthly climate report, early analysis suggests this March could rival or even surpass the record warmth of March 2012. One metric indicates the month may have set a new benchmark: more long-term weather stations recorded their warmest month ever in March 2026 than in any other month on record, including historically extreme periods such as the Dust Bowl summer of 1936.
Scientists say climate change has increased the likelihood of such extreme heat events. The March heat wave is estimated to have been made more than five times more likely due to long-term warming trends.
Source: The Weather Channel