The radar shows that our next storm has already made landfall on the west coast and is heading toward Colorado.

The reality is that we are tracking not one but three storms that will bring snow from Thursday night through next Wednesday. Our Powder Finder (http://opensnow.com/powder) is showing big-time snow totals, especially in California and Arizona. Colorado could see similarly impressive totals, but our powder finder only shows the forecast out to 5 days (through Monday), and a good bit of our snow will fall after that, on Tuesday into Wednesday.

We are going to see three distinct periods of snow as each storm passes through.

The first round of snow will start on Thursday late afternoon and continue through Friday morning or midday. This snowfall will favor the southern mountains with 4-8 inches while other areas receive 2-5 inches.

The second round of snow should arrive on Saturday and continue through sunrise Sunday morning. The snow on Saturday will favor the southern mountains with another 5-10 inches, and then the heaviest snow should shift to the central and northern mountains on Saturday night as the wind direction switches from the southwest to the west and northwest.

The third and final period of snow should begin on Sunday night and continue through Tuesday evening. Like the previous storms, this one will initially favor the southern mountains on Monday and Monday night, with heavier snow shifting to the central and northern mountains on Tuesday into Wednesday. I have the lowest confidence in the forecast for this third storm as all models continue to change the details of their forecasts.

The best times for skiing powder will be…

- Southern mountains on Saturday, Monday, and Tuesday (maybe Telluride on Wednesday morning)

- Central mountains on Sunday, Monday, and Tuesday

- Northern mountains on Sunday, Tuesday, and an outside chance for Wednesday morning

Snow amounts

The southern mountains should see the most snow. The University of Utah model’s forecast for Red Mountain Pass (between Telluride and Silverton) is for a whopping 40-70 inches of snow as a total for all three storms. I think this is optimistic and 25-50 inches is a more likely scenario. This is still a lot of snow no matter how we think through the details.

The central mountains should be in the 15-40 inch range according to this compilation of models. The average of about 2 feet seems reasonable if not a bit optimistic since the first two storms may not drop a lot of snow on the central mountains.

And the northern mountains have the widest range, from 5-35 inches. Hah - that should cover it! I think 1-2 feet is a good bet.

Here is the precipitation forecast from the American GFS model. Multiply by about 15 to estimate snowfall. This is a 7-day forecast, so look at the general pattern rather than the specific locations of any bullseyes of precipitation.

The biggest wildcard in my mind is what happens with the track of the storm on Monday, Tuesday, and Wednesday. If the storm slows down a bit, there could be an extended period of winds from the northwest or north, and this could bring additional snow to Telluride, Silverton, Irwin, Powderhorn, and some of the northern mountains near I-70. It’ll take another few days for the models to figure this out.

We have had a remarkable run of snow for two months, between mid-November and late January. After the three storms that will hit in the next week, we will likely see an end to our snowy streak and transition to a drier weather pattern for 7-10 days.

Here is the weather pattern from January 20-25. The cool blue colors show stormy weather, and indeed it will snow during most of these days.

Then from January 25-30, notice how the stormy weather moves east and a ridge of high pressure (bulging lines to the north) sets up over the west coast. This should push us toward drier weather , though I can’t rule out a storm sneaking in from the north and northeast.

And the weather pattern will stay similar from January 30 - February 3 with a ridge over the west coast and a trough in the east.

Longer-range models then start to show the west-coast ridge breaking down between about February 5-10, which could open the storm door once again. Of course forecasts that go out to 2-3 weeks are not super accurate, so this long-range forecast is a working hypothesis that will change!

Thanks for reading!

JOEL GRATZ

I am a fan of fun in the mountains AND learning about the mountain environment. Please take a moment to consider making a donation to get these kids up to the Keystone Science School for 3 days of fun and learning in March. I am thrilled that OpenSnow contributed $100 toward their tuition and transportation. Their teacher, Robert Cooper, emailed me and asked for a shout out because “I often give some press to great companies doing great things, and these are great kids doing great things.” Sounds great to me! More info here: https://www.gofundme.com/keystone-science-school-experience

 

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, Abasin, Winter Park, Berthoud Pass

East of the Divide
Eldora, 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