Snowpack

Adding to yesterday's discussion, below is one more map showing the snowpack across the western United States. The numbers and colors show the percent of average snowpack in each major river basin. The snowpack for most of the west is near or above average, and the numbers in Colorado are amazing with the statewide snowpack at about 140% of average. The sensors that measure the snowpack (SNOTEL), as well as the work that goes into making the map, are all funded by our tax dollars. Whether or not you agree with how the government spends all of our money, I hope we can agree that relatively low-budget items like collecting and analyzing these environmental data are quite useful to our community and for water managers.

Tuesday

Weatherwise, it won’t be a very interesting day. A storm will move over Colorado from the north and should touch off some showers, mostly over the southeastern mountains. The latest models have pushed any chance of accumulations toward the southeast mountains, and while that’s fun for maybe Monarch, the Sangre de Cristo range, the Wet Mountains, and the Spanish Peaks, it’ll likely mean mostly dry weather for the rest of the state.

Science-wise, the storm on Tuesday does give us a chance to have fun with satellite imagery.

On Monday night, the Tuesday storm was over eastern Montana. But you can’t see it in the infrared image below, which uses temperature to shows clouds. You can’t see the storm because there are virtually no clouds associated with the system.

To see the storm, we’ll look to another type of satellite imagery which measures the amount of water vapor in the upper part of the atmosphere. The great thing about water vapor is that it is everywhere, even in a dry atmosphere, so it allows us to see swirls in the atmosphere even in the absence of clouds. Sure enough, in the image below, you can see the swirl over eastern Montana, and this will be over Colorado on Tuesday afternoon and help to generate a few showers, mostly over the southeastern mountains.

Wednesday

The storm that we were expecting is going to be delayed, so this should be a drier day for most mountains.

Thursday & Friday

Unless the storm continues to slow down (a possibility), we should finally see snow pick up in the southern mountains later on Thursday or Thursday night and the snow should continue through Friday. Friday has a chance of being a powder day in the southern mountains. Below is the University of Utah multi-model forecast for snow at Wolf Creek, showing the uptick on Thursday night through Friday.

This will be a warm storm with dense snow. The central and northern mountains might see a burst of snow on Friday, though my confidence is low for these regions.

Saturday 3/23, Sunday 3/24, Monday 3/25

We could see light snow during any of these days. The storm from Friday could hang around through Saturday, and then another weak system could arrive on Sunday and stay through Monday. None of these storms are bringing a lot of energy, and they could drift or move erratically, and this is why I have low confidence in the snow forecast and am trying not to promise too much in the way of snow accumulations.

Tuesday 3/26

Regardless of the uncertainty in the forecast in the previous days, it continues to look like Tuesday, March 26, will be dry.

Wednesday 3/27 – Friday 3/29

I’ll hold on to the expectation that we’ll see a storm late next week. Since the models can’t even agree on the timing for the storm that will arrive in 2-3 days, it doesn’t make much sense to speculate about the details for a storm that is still 8-10 days away.

Thanks for reading!

My next update will be on Wednesday morning.

JOEL GRATZ

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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