Summary:

Snow Saturday night, mainly for the foothills and mountains along and east of the divide. Then dry Sunday and Monday, with light snow from Monday night through Wednesday night in northern Colorado along and north of I-70. Thursday and Friday will likely be dry, then a change in the storm track might bring snow back to the entire state around January 6th, plus or minus a few days.

Details:

Clouds will increase on Saturday afternoon as a storm drops into Colorado from the north. Look for snow to begin around sunset and last through the early morning hours. The best accumulations of 3-6 inches will be along and east of the divide (Eldora, Winter Park, Loveland, Abasin, Keystone), with just light snow or flurries for the mountains further west like Beaver Creek and Aspen.

Sunday and Monday will see a break in the action, then a moist northwest flow will bring flakes back to northern Colorado on Monday evening though New Years Day. I still don't know if we'll see just a few flakes or 3-6 inches over this time frame. The American GFS model shows 6+ inches while the European shows very little. I've noticed that the European seems to under forecast accumulations from northwest flow, so I'll side more with the GFS model and forecast a few inches for the northern areas.

Late next week and early next weekend will likely be dry, then the atmosphere will transition to a new pattern with a trough in the west and a more direct path to moisture from the Pacific Ocean. I still have no confidence in the details of the weather in this new pattern, so I can't talk about snow accumulations for Colorado. But things at least look favorable in the longer term. 

The weather pattern will change over the next 7-10 days. The ridge off the west coast will (likely) be replaced with a trough. Source: Penn State e-wall

JOEL GRATZ

PS - My landing in Calgary Friday night (enroute to CMH Monashees on Saturday) was incredible. A cold front blew through about two hours before our flight arrived from Denver, and after circling for 20 minutes waiting for a window, we landed in moderate snow with sustained 35mph winds, gusting to near 50mph. We were able to land in this wind because it was a direct headwind, not a cross wind. It was an amazing sight out the window seeing the snow blowing sideways as our pilots did a remarkable job getting us on the ground safely. Whew! Calgary sits out on the flat plains east of the mountains, and the weather here is usually very different than the weather in the mountains to the west in British Columbia (just like Denver weather compared to the weather in the mountains). So even though it's windy here in Calgary, it won't be that way further west.