Boise, ID – Idaho could be in for a snowier and stormier winter than usual, with the 2025-26 Winter Weather Outlook warning of an elevated risk of heavy snowfall and disruptive storms from December through February.
According to the National Weather Service (NWS) Climate Prediction Center, weak La Niña conditions are forming this fall, likely shifting to a neutral phase by mid-winter. Historically, these patterns bring colder air into the northern Rockies and enhance storm tracks across the Pacific Northwest — often translating to above-average snowfall for Idaho’s mountains and valleys alike.
Meteorologists stress that the forecast is preliminary. Short-term atmospheric drivers, including the Arctic Oscillation (AO) and Madden-Julian Oscillation (MJO), can swing conditions sharply. These shifts may turn quiet stretches into sudden, heavy snow periods, or bring unexpected cold snaps with dangerous travel conditions.
Still, the early signal suggests above-normal snowfall potential statewide. Northern Idaho, including Coeur d’Alene and the Panhandle, could see enhanced snow totals. Central regions such as McCall and Sun Valley may face prolonged mountain snow that fuels avalanche risk, while southern cities like Boise, Twin Falls, and Pocatello could encounter several impactful winter storms despite their typically milder patterns.
Past winters with similar climate setups show a wide range of outcomes. Some La Niña and neutral winters brought moderate accumulations, while others delivered more than 100 inches of snow in mountain regions, leading to avalanches, road closures, and extended school cancellations.
Travel challenges are a major concern for residents. Interstates such as I-84, I-90, and I-15 frequently see closures or long delays during severe winter storms, especially in mountain passes where whiteouts and icy conditions are common. January and February are historically the most active months for strong winter systems in Idaho.
The official NWS winter forecast will be issued October 16, but emergency management agencies encourage residents to prepare now. That means servicing heating systems, stocking up on salt and shovels, and equipping vehicles with chains, blankets, and emergency supplies.
