Forecast models indicate that the Polar Vortex will strengthen in late December 2025 after a split and disrupted phase earlier in the season. The recovery is expected to influence North American and European weather in January 2026, potentially sending colder air southward while reorganizing jet stream flow.
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.
A powerful windstorm left over 120 000 customers, an estimated 300 000 people, without power on Wednesday, December 17, 2025, after winds of up to 90 km/h (56 mph) hit parts of the Lower Mainland.
A strong Alberta Clipper storm will move through northern Ontario on Thursday and Friday, December 18 and 19, 2025, dropping 20–30 cm (8–12 inches) of snow, gusts up to 80 km/h (50 mph), and a sharp temperature drop. The system will create blowing snow and flash-freeze conditions on major highways, including routes between Kenora and Thunder Bay.
A sudden stratospheric warming event has begun, deforming the Polar Vortex and setting the stage for a colder start to winter across the United States, Canada, and Europe.
A record-breaking bomb cyclone ripped through Newfoundland from November 4 through 5, 2025 bringing along Category 2 hurricane force winds, coastal flooding, and causing widespread damage across the region.
A developing bomb cyclone over the northwest Atlantic is expected to reach Newfoundland on Tuesday, November 4, 2025, with wind gusts exceeding 100 km/h (62 mph) and waves reaching up to 6 m (20 feet).
A large sea surface temperature anomaly has developed in the North Pacific Ocean, extending toward the U.S. West Coast. Forecasts suggest the anomaly could help trigger colder-than-average conditions across central and eastern United States and Canada during the upcoming 2025/26 winter season, with a weak La Niña further reinforcing the setup.
A strong atmospheric river is forecast to shift southward along the British Columbia coast between September 26 and 29, 2025, bringing several low-pressure systems and periods of heavy rainfall to Vancouver Island and the South Coast. Forecasts suggest up to 100 mm (4 inches) of rain in west-facing coastal mountains, with persistent showers likely across the Lower Mainland.
A severe hailstorm struck southeastern Alberta, Canada, on August 20, 2025, producing wind gusts up to 150 km/h (93 mph), large hail, and widespread damage to crops, livestock, and infrastructure.
