Next Arctic Air Mass Forms in Western Russia; Threat to Europe?
12/11/2025, 8:33 am EST
At The Surface, La Nina Strengthened Last Week. However, Subsurface Cool Fuel Diminishing.
12/15/2025, 4:07 pm EST
Climate Impact Company Week 2-4 Outlook
North America
Issued: Friday, December 12, 2025
Highlight: Warm U.S. pattern ahead while frigid weather is locked in Canada.
Charts of the day: Current and projected North America snow cover/snow depth.
Discussion: The farther south reach in the East U.S. of snow cover has biased early December exceptionally cold. In 15 days, the southward extension of snow cover shifts to the West U.S. while retreating to Canada in the East.
Week-2 Ahead Forecast valid December 21-28, 2025: Warm U.S., frigid Canada.
Discussion: The intense Pacific “atmospheric river” storm track across California to the Great Basin is releasing mild maritime air eastward of the Continental Divide extending anomalous warmth to the Atlantic Seaboard. Canada is very cold and the attendant chill should extend southward across snow cover.
Week-3 Ahead Forecast valid December 28, 2025-January 4, 2026: Still warm while Canadian chill retreats westward.
Discussion: The warm Pacific influence is maintained into early January while the Canadian chill retreats to West Canada.
Week-4 Ahead Forecast valid January 4-11, 2026: West Coast storminess continues, fuels warm pattern to the east.
Discussion: In the extended range forecast for the first full week of January the mild pattern continues fueled in-part by mild Pacific influence.