Quarterly Climate Impacts and Outlook for the Western Region for December 2024–February 2025. Dated March 2025.

Winter temperatures were above normal across the Southwest with California and Arizona both ranking as the fourth warmest on record. Temperatures were closer to normal in the Pacific Northwest and northern Rockies with some areas of below-normal temperatures in Montana. Winter precipitation was much below normal across the Southwest. Much of Oregon, eastern Washington, southern Idaho, and Montana saw above-normal winter precipitation.

This NIDIS-funded study, led by researchers at the University of Colorado Boulder/Cooperative Institute for Research in Environmental Sciences (CIRES), identified challenges in predicting seasonal water supply during drought years in snow-dominated basins of the western United States due to climate warming.