Tuesday will be warmer and sunny. The cold morning temperatures of -10°F to 0°F will rise to 15-20°F by early afternoon.

Then for the storm starting on Wednesday, there is a significant change to the forecast. Based on a model trend that started on Monday afternoon, I am going to reduce the snow forecast for most mountains because it appears that the duration of the storm will be shorter with most of the accumulating snow ending by Thursday evening. Most mountains will still enjoy two days of fun, soft conditions on Thursday and Friday, but the powder will likely NOT extend into Friday afternoon and Saturday.

On Wednesday morning and midday, there could be snow showers for the northern and central mountains though accumulations should be light.

On Wednesday afternoon, the intense snow should start around 2 pm at Steamboat in the far north and between 3-4 pm for most other mountains. This timing means that the last lift-serviced run of the day might offer a bit of fresh snow.

On Wednesday evening and Wednesday night, snow will fall for most mountains with the deepest totals around Steamboat and also on the northern side of the San Juan mountains around Telluride, Silverton, and Red Mountain Pass.

By Thursday morning, the deepest totals of 5-10+ inches should be around Steamboat, Telluride, and Silverton with most other mountains in the 3-6 inch range. Steamboat is favored because the wind direction should be perfect from the west or west-northwest, and Telluride/Silverton are favored because the storm energy will track over this area and they can do well with a wind from the west-northwest and northwest.

During the day on Thursday, the combination of instability (which allows air to rise and convert moisture into snow) and a flow from the northwest should deliver another few inches of snow during the day.

And on Thursday evening, we should see another few hours of snow after lifts close thanks to the combination of a final wave of energy and the jet stream moving overhead.

By Friday morning there should be at least a few fresh inches of snow that fell after the lifts stopped on Thursday afternoon.

Wrapping this together, the deepest storm total of 8-16 inches should be around Steamboat, Telluride, and Silverton. Other mountains that do OK in west and northwest flow (most of them, though check out the map below for the outliers) should be in the 5-10 inch range. These totals are respectable and should provide fun skiing but are lower than my forecast from yesterday mainly because of the shorter duration of the storm (we are no longer expecting meaningful snow on Friday into Saturday).

All of the latest models reduced their precipitation forecast compared to what I showed yesterday, and the CAIC WRF 2km model below is in line with the model consensus.

The timing of the storm means that Thursday morning will offer powder, though it’ll be on top of a harder base so we'll need 10+ inches to give us a shot at enjoying powder without hitting the bottom too much. Additional snow on Thursday should make conditions softer through the day, and then the final wave of snow on Thursday evening means that Friday could offer the most enjoyable powder because the base will be soft thanks to the previous ~30 hours of snowfall.

A caveat to all of this is that despite the pretty strong model consensus about how this storm will behave, models often make some mistakes when forecasting a fast-moving northwest flow, so there will likely a few surprises. I'll let you know if I see more data to support lowering or increasing the forecast.

On Friday the northern mountains might see clouds and light snow hang around though additional accumulations should be little to nothing.

Then Saturday should be sunny with a brief ridge of high pressure moving over Colorado.

The next storm could be a quick hitter sometime from late Sunday through Monday (January 5-6).

Another quick-hitting storm could move through around Thursday or Friday (January 9-10).

After January 10th, all models continue to show a stormy and cool weather pattern over the western United States.

This stormy pattern after January 10th is great news in general but does not guarantee big snow for us here in Colorado or in any particular area of the west. We’ll need to wait at least another few days to see how each individual storm will track.

Thanks for reading!

My next update will be on Wednesday morning. In the meantime, happy new year!

JOEL GRATZ

Geography Key

Northern Mountains
Steamboat, Granby, Beaver Creek, Vail, Ski Cooper, Copper, Breckenridge, Keystone, Loveland, Abasin, Winter Park, Berthoud Pass, Eldora, Rocky Mountain National Park, Cameron Pass

Along the Divide
Loveland, Arapahoe Basin, Winter Park, Berthoud Pass

East of the Divide
Eldora, Echo, Rocky Mountain National Park, Cameron Pass

Central Mountains
Aspen, Sunlight, Monarch, Crested Butte, Irwin, Powderhorn

Southern Mountains
Telluride, Silverton – north side of the southern mountains | Purgatory, Wolf Creek – south side of the southern mountains