https://www.boulderweather.com/tags/marshall-fire/Recent content in Marshall Fire on BoulderWeather.comHugo -- gohugo.ioenBoulderweather.comFri, 26 Jun 2026 00:00:00 +0000https://www.boulderweather.com/post/marshall-fire-weather-conditions/Fri, 26 Jun 2026 00:00:00 +0000https://www.boulderweather.com/post/marshall-fire-weather-conditions/ <h2 id="a-grass-fire-on-december-30-became-colorados-most-destructive-because-of-the-wind">A Grass Fire on December 30 Became Colorado's Most Destructive Because of the Wind</h2> <p><script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-1012089347386563" crossorigin="anonymous"></script> <ins class="adsbygoogle" style="display:block" data-ad-client="ca-pub-1012089347386563" data-ad-slot="1011306739" data-ad-format="auto" data-full-width-responsive="true"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> On December 30, 2021, a wind-driven fire swept out of the open grassland between <a href="https://www.boulderweather.com/boulder-county/superior/">Superior</a> and <a href="https://www.boulderweather.com/boulder-county/louisville/">Louisville</a> and destroyed more than 1,000 homes in a matter of hours, making the <a href="https://en.wikipedia.org/wiki/Marshall_Fire">Marshall Fire</a> the most destructive wildfire in Colorado history by structures lost. What turned a late-December grass fire into a catastrophe was not the fuel alone but a textbook — and avoidable-to-understand — alignment of weather: hurricane-force downslope winds, a landscape parched by months of drought, and humidity in the single digits. This page walks through that meteorology, not to relive the day but because the same setup recurs along the Front Range and recognizing it is a genuine safety skill.</p>