DENVER — The skiing should be spectacular this holiday in Colorado's mountain resorts. The question is whether travelers will be able to reach the slopes.

A series of monster snowmakers is dumping several feet of snow by Christmas on Colorado's mountains. But the weather system that brought snow and rain to the West Coast could make travel to the mountains difficult in Colorado in coming days.

Several mountain passes have been closed because of heavy snow, and avalanche warnings scattered from Steamboat Springs south to the San Juan mountains has state highway crews closing Cameron Pass and other roads to clear heavy snow accumulation threatening drivers.

Late Tuesday afternoon, about 10 miles of Interstate 70, the main route from Denver to the ski resorts, was closed because of a collision between two trucks, one of which was carrying 40,000 pounds of an explosive gel. Highway officials said traffic would be rerouted for at least four hours.

Lake Dillon Fire-Rescue spokesman Steven Lipsher said the gel was in a container and considered stable. The driver of a tow-truck that hit the tanker truck carrying the gel was injured and taken to the hospital.

Highway officials were warning holiday travelers headed to the high country not to set out without emergency supplies such as extra water and blankets in case they get stuck.

"We really want motorists to be ready for winter traveling conditions," Colorado Department of Transportation Mindy Crane said.

Meteorologists say Colorado's mountains would see epic snowfall totals by Christmas. One ski resort, Wolf Creek in Pagosa Springs, reported 50 inches between Saturday and Tuesday, with snow continuing to fall and predicted to keep dropping through the weekend.

"It's really not going to stop snowing down there for a while," National Weather Service meteorologist Kathy Torgerson said.

Silverton in southwest Colorado was cut off for a while Tuesday when mountain passes were closed for avalanche control. Residents were cross-country skiing and snowmobiling to get around the town, which sits at about 9,300 feet.

"We've had 22 inches of snow in the last 24 hours," said Mark Esper, editor of the Silverton Standard. "It started out as a wet, slushy snow and now it's all nice and fluffy."

It was a much different scene in the Denver area and the eastern half of the state, which haven't received snow. The NWS warned motorists leaving Denver for mountain trips to expect treacherous driving conditions.

"Traveling over the mountain passes will become nearly impossible at times as heavy snow falls over the mountains," a warning said.

A truck carrying 2,500 gallons of a de-icer, magnesium chloride, overturned near Silverthorne on Tuesday, causing delays on Interstate 70 near several ski resorts. Silverthorne Police said weather didn't cause the wreck and that traffic was moving normally by late afternoon.

Farther north, it wasn't immediately clear whether icy road conditions caused an accident in Clear Creek County that left a firefighter injured. Clear Creek Fire Authority Fire Chief Kelly Babeon was hospitalized Tuesday with non-life threatening injuries after he was struck by a vehicle near Empire as he helped a motorist.

Snowfall was blamed for canceling flights at some of Colorado's smaller mountain resort airports, including Yampa Valley Regional Airport in Steamboat Springs. The system was also blamed for torrential rains in California and heavy snow in Wyoming. In Laramie, Wyo., the University of Wyoming closed early Tuesday for staff working through the students' winter break.

But at Denver International Airport, the ground was dry and arriving travelers were giddy at the prospect of snowy holidays — assuming they could make it to the slopes.

"I saw the forecast, and it's all good news. That's why I'm here," said 60-year-old Tim Callahan, of Boston, who arrived in Denver Tuesday for a holiday skiing trip to Breckenridge.

Aspen ski slopes boast new snow, more expected

At Aspen/Snowmass, the Aspen Skiing Co. was reporting close to a foot of new snow at both Aspen Highlands and Buttermilk at about noon Tuesday. Both ski areas had 11 new inches, along with 8 inches at Snowmass and Aspen Mountain.

The Skico was reporting 19 inches of new snow at Highlands in the past 48 hours, and 15.5 inches at Buttermilk over the same period. Snowmass had 13 inches over the previous 48 hours and Aspen Mountain picked up 10 inches, the company reported.

What was falling as snow at higher elevations, however, fell as rain Monday on the streets of Aspen.

A winter storm warning remains in effect for the mountains surrounding Aspen until 5 p.m. Thursday. The National Weather Service is calling for a lull in the snow Tuesday night and early Wednesday, before the snowfall picks up again Wednesday afternoon and into Thursday.

Accumulations of 2 to 4 feet will be common above 9,000 feet, but some areas could see up to 6 feet of snow, according to the weather service. The heaviest snowfall is expected to fall from the top of the Grand Mesa to the Elk Mountains, including the area surrounding Crested Butte, the weather service said.

At lower elevations, including Aspen, more rain is likely Wednesday. Rain and snow are forecast on Thursday.

The Aspen Times contributed to this report.