Mountain Passes

High-elevation passes — Independence Pass (CO-82), Cottonwood Pass, and Trail Ridge Road — typically close October–November and reopen May–June, depending on snowpack. I-70 corridors including Eisenhower Tunnel, Vail Pass, and Floyd Hill stay open year-round but can have chain requirements during heavy snow events.

Chain laws require vehicles to carry or use tire chains or approved snow tires during severe winter conditions. CDOT activates chain laws on I-70 west of Denver (especially Glenwood Canyon and Vail Pass) during significant winter storms. WYDOT, UDOT, and MDT all have similar requirements on key corridors — check real-time DOT alerts before driving high-elevation routes.

PeakScout polls CDOT, WYDOT, UDOT, and MDT road condition feeds every 15–30 minutes. During major storm events, polling frequency increases. Status badges reflect official DOT designations (Open, Partial, Closed) plus NOAA road weather station data where available. Always verify with the state DOT before a trip.

The most hazardous winter pass corridors include Teton Pass (WY-22) for steep grades and drifting snow, Wolf Creek Pass (US-160, CO) for avalanche exposure, Loveland Pass (US-6, CO) as an I-70 alternate with no chain-ups, and Going-to-the-Sun Road (MT) which closes entirely from October to late May. Always check conditions before departure and carry chains.