Up to 18 inches of snow could accumulate over Summit County this week, according to the National Weather Service, and OpenSnow meteorologists say certain mountains could record up to 2 feet.

Summit County is under a winter weather advisory from 1 p.m. Monday, Dec. 12, until 5 p.m. Wednesday, Dec. 14, with “blizzard conditions” expected during that time frame, which includes wind gusts up to 60 miles per hour and heavy bands of snowfall. 

Meteorologists at both the National Weather Service and OpenSnow say that snowfall totals remain uncertain as the storm approaches, but since the storm is tracking across Colorado in a northwest direction, OpenSnow meteorologist Joel Gratz says the variable wind direction and possible lack of moisture could make it difficult to accurately predict how much will fall over the mountains. 

OpenSnow predicts that northern mountains and those around Summit County could see between 10 to 25 inches of snowfall up until Thursday evening, and the National Weather Service of Denver/Boulder predicts between 6 to 10 inches and up to 18 inches for areas in the Gore Range. 

“The summary is that Tuesday and Wednesday should be powder days with patience leading to some sneaky deep snow,” Gratz wrote in his snow report. “The snow could even last into Thursday morning. As for storm totals of 1- to 2-plus feet, I think this is reasonable due to the duration of the storm with the caveat that the lack of moisture could somewhat inhibit the deeper snow totals.”

Gratz expects the snow to fall sporadically over all of Colorado’s mountains Monday night since it will move across the state in snow bands. Then he says the storm is expected to strengthen between Tuesday morning and Thursday morning and wrap moisture and storm energy around and back into Colorado in a counterclockwise direction. He says there will be a period of about 48 hours of snowfall in the mountains. 

The National Weather Service’s forecast shows that the storm is expected to strengthen Monday night and dump the most snow Tuesday. It does mention that snow showers could stick around through Thursday, but travel and conditions are predicted to be the worst Tuesday and Wednesday. 

Gratz said the variable wind direction makes it difficult to predict snow totals for specific mountains since it’s still a bit early to know exactly what is in store. 

“The wind direction is important to figure out what individual mountains are favored, though with an extended period of 48 hours of snow, even if the wind direction oscillates between these two directions and favors some mountains more than others at certain times, the outcome over the duration of the storm should still be favorable for the spots that do well with northwest winds,” Gratz wrote. 

After the storm, it’s expected to be cold and dry until the end of the weekend, but Gratz says there’s potential for a bit of storminess to return to Colorado around Dec. 18-24, bringing a cool and low-moisture weather pattern toward the Rockies. 

“We could get lucky and see moisture and storm sneak in from the west or southwest during this time, but the odds are slightly against that,” Gratz wrote. “What this means for the week leading up to Christmas is that we could see more snow, but at the very least, cool-ish temperatures and a low sun angle will preserve the snow that we have, and our snowpack should be near to above average thanks to the already healthy snowpack and the storm from December 12-14.”

For more weather information, visit OpenSnow.com and Weather.gov/bou. To see live road conditions and alerts, visit COTrip.org.