• Strong atmospheric river to impact California, up to 500 mm (20 inches) of rain forecast for Sierra Nevada

    Three atmospheric rivers are expected to impact California between December 20 and 25, 2025, producing 250–500 mm (10–20 inches) of rain over the Sierra Nevada and 75–180 mm (3–7 inches) over southern coastal ranges. The strongest system is forecast to peak on December 23–25 with IVT values surpassing 750 kg m⁻¹ s⁻¹ and AR3–AR4 intensity.

  • Coast-to-coast storm with 232 km/h (144 mph) gusts leaves 1 dead, 2 injured across Northwest and Rockies

    A powerful windstorm with gusts reaching 232 km/h (144 mph) battered parts of the Pacific Northwest and Rockies this week, leaving one dead, two injured, and hundreds of thousands without power by December 18, 2025. The deep low-pressure system continues moving east toward the northern Plains and Midwest, sustaining severe winds and wildfire risks.

  • Blizzard conditions and destructive winds forecast for the northern Plains and northern Rockies, U.S.

    A fast-moving winter storm is forecast to bring widespread blizzard conditions and destructive winds across parts of Montana, North Dakota, and Minnesota through Wednesday night into Thursday, December 17 into 18, 2025. The system, driven a deep low-pressure trough, is generating gusts up to 110 km/h (70 mph) and localized peaks over 130 km/h (80 mph) in leeward mountain areas, potentially leading to whiteout conditions, road closures, and power outages across the region.

  • Above-normal atmospheric river activity forecast for Northern and Central California in late December

    The Center for Western Weather and Water Extremes (CW3E) at UC San Diego forecasts above-normal precipitation for Northern and Central California between late December 2025 and early January 2026. The latest subseasonal outlook, issued on December 16, indicates high confidence in enhanced atmospheric river (AR) activity and persistent Pacific Ridge conditions during the period from December 22 to January 11, 2026.