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Colorado: Risks & Trends

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Same standard as every other page on this site: every figure below is independently sourced, and figures that vary across sources, or measure genuinely different things, are flagged as such rather than collapsed into one number that looks more precise than the underlying data actually supports.

The Marshall Fire (2021): Colorado’s most destructive wildfire on record

MetricFigure
Date December 30, 2021
Deaths 2
Burn injuries 8
Acres burned 6,026
Structures destroyed 1,084 (97% residential)
Structures destroyed by community 550 Louisville / 378 Superior / 156 unincorporated Boulder County
Damage $2 billion+
People evacuated 37,500+

Why this fire is a genuine outlier

The Marshall Fire happened in December, driven by hurricane-force winds following an unusually wet spring that grew heavy grass, then an extremely dry fall that cured it into fuel. It’s a fundamentally different mechanism from the deep-forest, summer wildfires covered elsewhere on this site, a fast-moving grass fire that reached suburban neighborhoods with almost no warning, driven by wind rather than drought-dried timber.

Avalanche deaths: a decades-long national lead

MetricFigure
Colorado avalanche deaths, 1950-2023 287
National ranking 1st, nearly double 2nd-place Alaska
Colorado deaths, last 12 winter seasons 62 (from 54 fatal avalanches)
National average deaths per year, last 12 seasons ~22

Colorado’s lead isn’t just about how many people recreate in its backcountry, it’s also about the terrain itself: the state’s relatively thin, dry continental snowpack is notoriously unstable, and weather events can leave lingering instability for weeks, longer than the faster stabilization typical in other snow climates.

What these two have in common

The Marshall Fire and Colorado’s avalanche toll both demonstrate that Colorado’s mountain and grassland terrain carries year-round risk in different forms: wind-driven grass fire risk in the shoulder seasons and winter, and snowpack instability throughout the backcountry ski and recreation season. Neither risk fits neatly into the conventional “fire season” or “storm season” framing that applies in most other states covered on this site.

Sources