A major winter storm moving through Colorado was expected to drop plenty of snow in the mountains Tuesday night and cause road conditions to deteriorate until Wednesday morning, according to the National Weather Service.

The storm is behaving similarly to how forecasters thought it would, causing the biggest impacts in the mountains, NWS Boulder Meteorologist Maggie Ideker said Tuesday night.

There’s still some uncertainty about how much snow the Denver metro area will see, Ideker said.

Snow totals will depend on how cold it gets, if rain turns to snow and if road surfaces become cold enough for the snow to stick.

A narrow band of heavier snow about 5 to 7 miles wide could cause a messy commute for drivers on Wednesday morning, and freezing temperatures may cause wet roads to become extremely slick as late as Thanksgiving morning.

According to Tuesday evening forecasts, the high end of expected snowfalls includes:

• Up to 4 inches of snow at DIA and in Brighton;

• Up to 5 inches in Northglenn;

• Up to 6 inches in Denver, Aurora, Broomfield and Boulder;

• Up to 7 inches in Arvada, Centennial, Highlands Ranch, Lakewood and Littleton;

• Up to 8 inches in Golden and Parker.

The mountains are also expected to see 2 to 3 more feet of snowfall by the time the storm wraps up Wednesday night, according to NWS snow forecasts.

The Colorado Avalanche Information Center warned backcountry travelers that the storm will bring dangerous avalanche conditions.

The most snow is forecast for West Elk Peak, the highest summit in Colorado’s Elk Mountains, which could see up to 55 inches of fresh snowfall between Tuesday morning and Thursday morning, NWS forecasters said.

Eastern Plains communities will see a few inches or less of snow, and the storm is expected to wrap up across the state around 11 p.m. Wednesday, forecasters said.

A winter storm warning remains in effect for areas above 9,000 feet until 5 p.m. Wednesday.

Winter weather advisories were to start for the foothills and areas south of metro Denver, including Castle Rock, around midnight Tuesday and remain in effect until midnight Wednesday, according to NWS forecasters.

Another winter weather advisory for Denver and the surrounding suburbs was to start at 2 a.m. Wednesday and expire at 2 p.m. that afternoon, according to NWS forecasters.

“Banded snowfall is possible Wednesday morning, leading to widely varying snowfall totals,” forecasters said in the advisory.

“Locations in the southwest Denver metro have the highest chance of winter weather impacts.”

Though Thanksgiving will be cold, with highs in the mid-30s across the Denver area, it comes nowhere near the coldest the holiday has been in the metro.

The coldest Denver Thanksgiving, a record set in 1919, saw temperature highs in the negatives with overnight lows near minus-18 degrees.

Cold, dry weather will continue through Saturday after Thanksgiving, with temperature highs forecast in the mid-30s across the Denver area and in the teens across the mountains.

A few mountain snow showers are possible Friday night into Saturday, forecasters said.

Otherwise, warmer and drier weather is expected through the weekend.