From Wikipedia: On December 30, 2021, shortly before 10:30 a.m. MST, grass fires broke out in Boulder County, Colorado, United States. Two fires were named by local fire authorities as the Marshall Fire and the Middle Fork Fire.
The causes of the fires are still under investigation, but the fires, once started, were spread widely by very strong winds. The stage was set by the extremely dry conditions experienced by that region of Colorado.
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