Morning dose of happiness

What more do you need to make you smile this morning?! Cute dog? Check! Fresh snow? Check!

Tuesday recap

We saw a snow showers early in the morning with 1-2 inches accumulating in the northern part of the southern mountains, around Telluride, Silverton, and Red Mountain Pass. Then the rest of the day was sunny.

Wednesday’s snow arrive early afternoon

Modern weather science is amazing. Forecasts are far from perfect but consider this event.

As I drove into the mountains on Tuesday night to see friends and family ahead of the storm, the sky was clear and calm with no indication that 24 hours later on Wednesday evening we would have intense snow and strong winds.

But modern weather science has told us for days to expect the storm on Wednesday evening, and so we have a multi-day heads up that a system is coming which should make driving tough for a few hours and deliver powder to most mountains. Go science (and the tens of thousands of people that have worked over the past 50 years to make this possible!).

A question I often get is ‘What makes a storm easy to forecast?’

This upcoming system is reasonably easy (that doesn’t preclude some surprises, of course). The storm is moving fast with defined start and end times, and the model forecasts have been consistent for days. There aren’t many tricks to consider.

Here is an early look at the system as it crosses Idaho, Wyoming, and Utah early on Wednesday morning.

There are no big changes to the forecast. Expect a dry morning on Wednesday, with a shot of intense snow arriving during the mid-afternoon and continuing through about Wednesday at midnight.

When the intense snow hits, the combination of snowfall rates of 1”+ per hour and strong wind may lower visibility enough to close some roads for a few hours, especially in the northern mountains.

What to expect…

* Timing. Snow should start first at Steamboat around 12-2pm and then will begin in the rest of the mountains 2-4pm. Snow will end by about midnight.

* Best powder. The last few runs on Wednesday could offer storm skiing (snowing, windy, low visibility) and the first run on Thursday should be the softest with fresh snow underfoot, clearing skies, and chilly temperatures in the single digits to low teens.

* Amounts. Most models are showing about 3-6 inches for most northern and central mountains, as well as the northern part of the southern mountains (Telluride and Silverton). Maybe a lucky mountain or two can break the 6-inch barrier and get up to 8 inches. The northwest winds of this system should favor mountains further west and north that do well with northwest winds (Winter Park, Loveland, Breckenridge, Vail, Aspen Highlands in the bowl, Telluride, Silverton).

Below, the latest forecast from the CAIC WRF high-resolution model (4km grid boxes) is consistent with its previous runs.

Below is the latest forecast from the CAIC WRF super-high-resultion model (2km grid boxes). This model shows an extra 1-2 inches compared to the 4km model above.

It is typical for higher resolution models to forecast more snow over the mountains, but this isn’t always the correct answer. It’ll be a fun test case to see if the higher-resolution model is on to something or if it’s out to lunch.

Enjoy the storm and the new snow!

December 13 - 20

On Thursday, December 13th, we’ll have fresh snow in the morning.

Then through the weekend and most of next week, I do NOT see anything in the models to suggest a significant storm. Maybe we’ll get lucky and something will sneak into Colorado, but odds are low. If we believe the European model, later next week (December 20-21) could bring some snow to the northern mountains.

December 21+

The European model insists that we’ll trend colder and stormier as we move toward Christmas and close to New Years.

The American model is only kinda-sorta on board with that scenario.

The tiebreaker in my mind is that our recent snowy periods have been on roughly 30-day cycles starting around the end of one month and continuing through the beginning of the next month. This would line up with the European model’s outlook for stormier weather the closer we get to the end of December.

Thanks for reading!

My next update will be on Thursday, December 13.

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