Record Warmest Winter Across Much of the West, Preliminary Data Shows

Preliminary data show meteorological winter 2025–26 was the warmest on record across a large part of the western United States, based on 131 years of climate data. The contiguous U.S. recorded its second-warmest meteorological winter as cooler conditions in the East limited a nationwide record.

Meteorological winter (December through February) has ended and preliminary data show it was the warmest on record across much of the western United States. Those findings are based on 131 years of climate data. The contiguous United States as a whole recorded its second-warmest meteorological winter, with cooler conditions in the East keeping the nation from its warmest overall winter. Many western locations also experienced below-average snowfall and signs of reduced mountain snowpack. Key findings: - A large swath from Southern California to the High Plains and Northern Rockies had its warmest meteorological winter on record, based on 131 years of data. - The contiguous U.S. recorded its second-warmest meteorological winter; cooler temperatures in the East prevented a nationwide record. - Several cities reported their warmest winter on record, including Salt Lake City (152 years of data), Tucson (130 years), and Rapid City (114 years). - Phoenix exceeded its previous winter temperature record by nearly 3 degrees. - Many western sites saw limited snowfall and diminished snowpack during the winter season. - A persistent ridge of high pressure over the West and a negative phase of the Arctic Oscillation were reported as factors that steered storms north and allowed warmer conditions to persist. Summary: The warm winter and reduced snowfall have left diminished mountain snowpack across parts of the West, which the article reports could have ripple effects as warmer months begin. Undetermined at this time.