Avalanche danger throughout Colorado was low on Monday, Nov. 18, except in Summit County, where state avalanche officials elevated the danger to moderate due to a persistent slab avalanche problem.

In the Tenmile and Gore ranges in Summit County, there have been reports of larger avalanches and obvious signs of instability like deep, shooting cracks in the snowpack above tree line, according to the Colorado Avalanche Information Center’s forecast for Monday.

The avalanches and shooting cracks are due to a weak layer of snow that fell in October and has since faceted, forming a weak layer near the ground, the forecast states. State avalanche officials say the problematic layer is only found above about 11,200 feet and only on northerly and east-facing slopes.

Colorado Avalanche Information Center forecaster Jason Konigsberg observed the snowpack on an east-northeast-facing slope near Mayflower Gulch, a popular backcountry skiing area in the Tenmile Range near Summit County, on Saturday, Nov. 16.

Konigsberg said in a video posted to social media Sunday, Nov. 17, that avalanche danger is low below tree line at Mayflower Gulch.

“The reason why is (because) the whole snowpack is soft,” Konigsberg said. “From the bottom, we have big grains or faceted snow and then the whole snowpack is faceting. It’s just soft. What we don’t have is a slab, which you need for an avalanche.”

As Konigsberg climbed up the mountain he said he started to encounter more wind-affected snow but it was still thin and hadn’t created much of a slab. He demonstrated that he was able to poke his pole all the way through the snowpack, indicating that there was not a slab.

“No slab, no worries about avalanches,” Konigsberg said.

But higher up on the ridge, Konigsberg said he found a slab and was able to trigger it by jumping up and down. These conditions are why avalanche danger is moderate in the Tenmile and Gore ranges, according to the Colorado Avalanche Information Center.

“I was able to trigger this really small avalanche, not enough to bury someone but a good indication of what you can expect on larger slopes,” Konigsberg said. “The slab is quite thick from recent wind drifting and it broke near the ground up by the ridge. And in other places it broke on a thin layer of facets that were recently buried by the drifted snow.”

Avalanche officials recommend sticking to slopes less than about 30 degrees, where avalanches are unlikely to occur. It is also recommended that those traveling in avalanche terrain choose areas protected from the wind and avoid steep slopes, especially if there are warning signs like cracking or collapsing snow.

A small storm moving into Colorado late Monday could impact the avalanche danger Tuesday, Nov. 19, and other parts of the state could see the danger level rise to moderate, according to the Colorado Avalanche Information Center.

To view the latest avalanche forecast, visit Avalanche.state.co.us.