Start and end your day early, and most slopes will be safe to travel on. If you travel in steep, exposed terrain, avoid small pockets of wind-drifted snow or slopes with wet, heavy snow deeper than your ankles. Avoid travel under cornices, especially as the day warms.
I-70 Corridor Denver to Georgetown, Berthoud Pass, Rocky Mountain NP
Berthoud PassSt. Marys GlacierJames PeakEldora
Vail / Summit County
◌ No Rating
Vail, Breckenridge, Keystone, Copper, Frisco, Tenmile Range — highest concentration of CAIC activity
Quandary PeakGrays & TorreysPeak 10Vail Pass
Sawatch Range / Mt. Elbert
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Leadville, Mt. Elbert (14,440ft), Independence Pass, Turquoise Lake, Chalk Creek drainage
Mt. ElbertMount MassiveIndependence PassChalk Creek
Aspen / Snowmass
◌ No Rating
Aspen, Snowmass, Maroon Bells, Ashcroft, Castle Creek
Maroon BellsCrested ButteAshcroftSnowmass Pyramid
Crested Butte / Gunnison
◌ No Rating
Crested Butte, Gothic, Schofield Pass, Cimarron, Blue Lake
Schofield PassPurple MountainBlue LakeGothic
Telluride / Lizard Head
◌ No Rating
Telluride, Rico, Ophir, Wilson Peak area, Lizard Head Pass
Wilson PeakBlack Iron LoopLizard Head
San Juan Mountains
◌ No Rating
Silverton, Ouray, Lake City, Animas River corridor, Red Mountain Pass, Engineer Pass
Red Mountain PassClear LakeAmerican Basin
Steamboat / Yampa Valley
◌ No Rating
Steamboat Springs, Rabbit Ears Pass, Zirkel Wilderness, Mount Zirkel
Mount ZirkelBuffalo PassSarvis Creek
Glenwood Canyon / Flat Tops
◌ No Rating
Glenwood Springs, Rifle, Marble, Crystal, Flat Tops Wilderness
Crystal MillFlat TopsGlenwood Canyon
Grand County / Granby
◌ No Rating
Winter Park, Granby, Grand Lake, RMNP west side, Byers Canyon
Colorado avalanche danger is provided by the Colorado Avalanche Information Center (CAIC, avalanche.state.co.us). CAIC issues forecasts for 12 distinct zones ranging from the Front Range to the San Juan Mountains. Danger is rated 1–5 (Low to Extreme) across three elevation bands. Check the elevation strip above for the current statewide mode, and scroll down for zone-by-zone breakdowns.
CAIC rates danger 1–5 (Low/Moderate/Considerable/High/Extreme) across three elevation bands: above treeline, near treeline, and below treeline. Each zone gets a rating based on current snowpack stability, weather trends, and recent avalanche activity. CAIC issues forecasts daily during the snow season (typically November through mid-June). The Front Range, Vail/Summit, and San Juan zones have the most field observation coverage.
Level 1 (Low) — Generally safe conditions on most terrain; natural avalanches very unlikely; human-triggered avalanches unlikely. Level 2 (Moderate) — Heightened caution on slopes >30°; natural avalanches unlikely but human-triggered slides possible on specific terrain. Level 3 (Considerable) — Dangerous conditions; human-triggered avalanches likely on steep terrain; avoid convex rolls and terrain traps. Level 4 (High) — Very dangerous; natural avalanches likely; avoid all steep avalanche terrain. Level 5 (Extreme) — Avoid all avalanche terrain.
Colorado ski areas work actively to manage avalanche hazard within their operating boundaries through regular bombing and control work. However, ski area boundaries often mark the edge of controlled terrain — backcountry terrain immediately adjacent to ski areas is NOT controlled. Many serious incidents occur in "sidecountry" accessed through ski area boundaries. Always check ski area rules for backcountry access gates and understand that anything outside the operating boundary is uncontrolled avalanche terrain.
Primary avalanche season runs December through March, with the most fatalities occurring January–February. However, CAIC often extends daily forecasts through mid-June due to spring storm cycles and persistent weak layers in the continental snowpack. The San Juan Mountains and Front Range above treeline can see avalanche cycles as late as June. The shoulder seasons (Nov and Apr–Jun) are particularly dangerous because riders underestimate conditions with minimal daylight and variable snowpack.
Check PeakScout at /colorado/avalanche for the current statewide elevation-based danger ratings and zone-level details. Always verify directly at avalanche.state.co.us for the full text forecast. During active storm cycles, CAIC issues morning updates and sometimes afternoon updates. Check CAIC social media (@avalanche_info) for real-time updates during storm events. Also check CPW and local SAR for any trail closures or accident reports.
A persistent weak layer is a buried snow layer — often composed of faceted crystals (sugar snow) or depth hoar (cup-shaped crystals) — that remains unstable for days to weeks after it forms. Colorado is particularly prone to persistent weak layers due to the continental snowpack: cold temperatures at high elevations create depth hoar near the ground while mid-storm warm layers can create buried surface hoar. These layers can be triggered remotely, propagate across wide distances, and produce very large avalanches. CAIC forecasts highlight when persistent weak layers are the primary problem.
During High (Level 4) danger, natural and human-triggered avalanches are likely on steep terrain. Most experienced backcountry users avoid avalanche terrain entirely at Level 4 — this means no travel on slopes >30°, no stopping in terrain traps, no crossing below avalanche paths. Level 4 days are typically rest days in Colorado avalanche decision-making frameworks. If you must travel, stay on low-angle terrain (<25°) well away from any avalanche runout zones.
An Avalanche Watch (Level 3) means dangerous avalanche conditions are possible — conditions favor natural or human-triggered avalanches. Avalanche Warning (Level 4–5) means imminent danger, natural avalanches are likely or occurring, and travel in avalanche terrain is not recommended. Watches are posted by NWS or CAIC when incoming storms are expected to overload the snowpack; Warnings are issued when danger has already risen to High or Extreme. CAIC posts their own avalanche advisories separate from NWS winter storm warnings.
Colorado avalanche conditions are driven primarily by: (1) new snow weight and rate — rapid accumulations (>1"/hr or >12" in 24h) create storm slab problems; (2) wind direction — Colorado has dominant westerly winds that load leeward (E/NE) aspects with dense wind slabs; (3) temperature swings — warm events melt-bond weak layers, then refreeze into hard slabs that store energy until triggered. Spring storms with warm temps and rain-on-snow are particularly dangerous across the Front Range and Vail/Summit zones. CAIC rates these hazards in their daily bottom line.
Data Source: Colorado Avalanche Information Center (CAIC, avalanche.state.co.us). Forecasts sourced via avalanche.org v2 API with 8-hour cache. Always verify directly with CAIC before entering avalanche terrain. Colorado Ski Safety Act (C.R.S. § 33-44-101 et seq.) applies to ski area boundary zones; backcountry avalanche responsibility is governed by Colorado's Outdoor Activity Liability Act (C.R.S. § 33-41-101).
Safety Notice: Avalanche danger varies by aspect, elevation, and local terrain traps. Zone ratings are broad — conditions vary within each zone. PeakScout aggregates CAIC data as an informational aid only. Always carry and know how to use avalanche rescue equipment. Travel with trained companions. Colorado Outdoor Activity Liability Act (C.R.S. § 33-41-101) applies to backcountry use. Terms of Service · CO Winter Hub · Colorado Home