Avalanche Warnings Issued for Thanksgiving

Avalanche warnings are in place across Colorado as travelers set out to meet family and friends for Thanksgiving.

Warnings issued by the Colorado Avalanche Information Center (CAIC) and relayed by the National Weather Service (NWS) are in place until Thursday evening for the West Elk Mountains.

Park Range, Flat Tops, Gore Range, Indian Peaks, Sawatch Range, Elk Mountains, and the western and southern San Juan Mountains all have warnings in place until Wednesday evening.

“Large and dangerous avalanches will be very easy to trigger in many places,” an NWS update said.

“Travel in backcountry avalanche terrain is not recommended in the mentioned areas.”

Thanksgiving travelers should be particularly wary when moving under slopes steeper than about 30 degrees.

An avalanche is a rapid flow of snow, ice, and debris down a mountainside. They occur when the structural integrity of the snowpack is compromised, causing it to slide downhill under the force of gravity.

Avalanches can be small and harmless or massive and destructive, posing significant risks to people, wildlife, and infrastructure.

The warnings come following heavy winter storms, which have seen several feet of snow dumped in some places.

“We don’t see many storms through the winter that can be measured in feet, not inches, so when we do, pay attention, especially when feet of snow land on a thin and weak early-season snowpack,” the CAIC said in its Central Mountains Regional Discussion on Wednesday.

“There will be plenty of avalanches large enough to bury or seriously injure you.”

Newsweek has contacted the CAIC via email for comment.

The bulk of natural avalanches were expected to occur on Tuesday night, “with lingering slopes failing as more snow or wind-loading tips the scales through Wednesday.”

Human-triggered avalanches are very likely throughout the holiday, the CAIC said.

Andrew McWilliams, a forecaster at the CAIC, submitted a field report from Glacier Peak near the town of Montezuma on Tuesday, saying, “I observed a reactive snowpack and easily made small avalanches on steep slopes below tree line on easterly-facing slopes.”

He continued, “The weight of the storm snow made the snowpack reactive, but it was breaking into older, weak snow where I traveled. With additional snow in the forecast tonight, expect conditions to remain dangerous for the next couple of days at least.”

Skiers and snowboarders out seeking some fresh powder for the holidays are advised that “this is not the time” by the CAIC.

“You need to dial it back and play it ultraconservative until conditions stabilize. Avoiding avalanche terrain is the only way to ensure your safety,” the update said.

Winter storm warnings are also in place in Wyoming, Alaska, and Utah, while winter weather advisories have been issued by the NWS for Michigan, Minnesota, New Mexico and Nevada.

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