Avalanche warnings issued for Thanksgiving

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

Warnings from the Colorado Avalanche Information Center (CAIC) and the National Weather Service (NWS) are in effect for the West Elk Mountains through Thursday evening.

Warnings are in effect through Wednesday evening for the Park Range, Flat Tops, Gore Range, Indian Peaks, Sawatch Range, Elk Mountains and the western and southern San Juan Mountains.

“Large and dangerous avalanches can be triggered very easily in many locations,” said an NWS update.

“Travel to backcountry avalanche areas is not recommended in these areas.”

Thanksgiving travelers should be especially careful when traveling 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 due to gravity.

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

The warnings come after severe winter storms that dumped several meters of snow in some places.

“We don’t see many storms in the winter that can be measured in feet rather than inches. “So when that happens, you should pay attention, especially if foot-deep snow lands on top of a thin and weak snowpack early in the season,” the CAIC said in its regional discussion on the Central Mountains on Wednesday.

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

Newsweek CAIC emailed for comment.

The majority of natural avalanches would be expected on Tuesday night, “with remaining slopes failing as more snow or wind loads tip the scales by Wednesday.”

Human-caused avalanches are highly likely throughout the holiday, the CAIC said.

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

He continued: “The weight of the storm snow made the snowpack reactive, but where I was traveling it broke up into older, weaker snow. With additional snow forecast for tonight, we can expect conditions to remain dangerous for at least the next few days.”

Skiers and snowboarders looking for fresh powder for the holidays are cautioned by the CAIC that “this is not the time.”

“They need to back down and be ultra-conservative until conditions stabilize. Avoiding avalanche terrain is the only way to ensure your safety,” the update said.

Winter storm warnings are also in effect for Wyoming, Alaska and Utah, while the NWS has issued winter weather warnings for Michigan, Minnesota, New Mexico and Nevada.

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