Above average snow could lead to more avalanches in Colorado, similar to the one that partially buried a semi on Vail Pass earlier this week.

Avalanches during the winter in Colorado are expected, but the Colorado Avalanche Information Center is using words like historic, extreme danger and very large to describe the threat in some places.

So far, there have been 17 avalanches in the last two days on Highway 550, and 26 others across the state. Officials say the conditions are not improving.

The CAIC rates the danger on a scale where 5 is the worst.

Many areas of the mountains, including Steamboat Springs, Vail, Summit County are level 4, meaning high avalanche danger.

The area around Gunnison is shown in black, designating extreme danger. That's something the CAIC only sees around five times in a decade.

Deputy Director Brian Lazar says they are expecting historic snow slides in that area, which could hit roads and valleys.

“Not only can we see very large avalanches breaking in the storm snow, but in some places in the state we've seen eight feet or more of snow,"Lazar said. "So if that were to avalanche, that would create very destructive avalanches."

Lazar says it could be enough to knock a train off the tracks.

Meanwhile, CDOT isn't saying you shouldn't drive through the mountains, but with a fresh round of snow and sleet on the roads, they urge people not to drive if you don't feel safe.

“We have seen numerous and rollovers along I-70 all the way from Morrison all the way to Glenwood Springs," CDOT communications specialist Stacia Sellers said.

CDOT says it has about 80 plows on I-70 on the mountain corridor and Denver metro area. It's still working with the CAIC to lower the risk of avalanches in the high country.

Avalanche mitigation work on Loveland Pass was successful, but it left a lot of debris in the road so U.S. 6 so it remains closed through the pass.