We’ve been talking about the forecast for this series of storms for days, and now it’s show time.

There will be two main waves of precipitation that move through Colorado between Friday morning and Monday midday.

* The first wave will hit on Friday through Friday evening. Expect steadier snow to fall from Friday mid-morning through the afternoon, favoring the northern and central mountains. Snow levels should be reasonable, around 9,000-ish feet, with snow above that and rain below. That means some lower-elevation base areas could see rain, but most slopes will see snow. Then showers will continue on Friday night into Saturday morning over the northern mountains. The best time to find powder will be Friday midday through the afternoon, and likely Saturday morning. If you have a choice in ski locations, head to the highest elevations (over 10,000 feet) to have the best chance for powder.

* Saturday will become very, very warm and the rain/snow level could push up to 11,000 feet. This would mean that any precipitation would be rain for most mountains, with just the summits of some mountains seeing flakes. The exception is the higher-elevation areas around Summit County, like Arapahoe Basin and Loveland, where the base elevation is close to 11,000 feet.

* The second wave will hit on Saturday night. This will be an incredible storm due to the amount of moisture in the air.

The amount of moisture will be about 400% of average, with a connection to Hawaii (see the lower-left of the image).

To put that amount of moisture into perspective, it’s about 5 standard deviations from the mean for this date. Of course, the mean is just a guess because we don’t have exact weather records of moisture going back tens of thousands of years, but no matter, this is a highly anomalous storm!

* Unfortunately, Saturday night’s moisture will be associated with very warm air, so expect rain for most areas below 10,000-11,000 feet. When the precipitation is more intense, it’s possible that snow could fall below 10,000 feet, but the take away is that Saturday night is going to be a soggy mess for lower elevations. By the time we get to Sunday morning, cooler air will arrive, which should drop snow levels down to 9,000-10,000 feet.

* On Sunday morning, you might find 6-12+ inches of thick, dense powder at the highest elevations, over about 10,000-11,000 feet. Then during the rest of Sunday, we’ll see showers throughout the day with a few more inches of accumulation.

* On Sunday night through Monday morning, a final push of colder air will hit Colorado and I expect that the northern mountains will pick up 2-6 inches of additional fluffy snow. Monday morning might be the best quality skiing of the weekend with a base of dense snow and some fluff on top.

Below is the forecast radar from the NAM-WRF 3km model. This is from Friday at 600am to Sunday at 600am. The time at the top is given in “Z” or “Zulu”. Subtract 6 hours to convert to Colorado time. For example, 1200Z = 600am Colorado time. If you cannot see the animated image below, click here: https://opsw.co/2uVgr9M

To wrap up, Friday will bring precipitation, Friday night will have some more in the northern mountains, Saturday will be showery and warm, Saturday night will be stormy with rain at all but the highest of elevations, then Sunday will be showery, and the storm will end on Sunday night and Monday morning with fluffy snow in the northern mountains.

Total snowfall at elevations over about 10,500 feet could be in the 12-24 inch range, and total snowfall below about 8,500 feet could be very little. This is based on the following precipitation forecast, converted at about a 10-to-1 or 12-to-1 snow-to-liquid ratio.

Again – seek the highest elevations, over 10,000 feet! To do this, you can look at Google Maps or the resort’s website to find the base, mid, and summit elevation. Or, we have that information here on OpenSnow – on the website, it’s in the blue bar that says “Day 1-5 Forecast”, and on the mobile app, it’s in small font just below the forecast data on the top half of the screen.

Following the fluffy snow in the northern mountains on Monday morning, we'll have dry weather on Tuesday, Wednesday, and Thursday. The storm that was in the forecast for Tuesday night and Wednesday morning has fizzled and will track further north.

The next chance for a storm will be between Thursday night and Saturday morning (April 12-14).

After that system, we might see a break next Saturday night and/or Sunday.

Then another storm could arrive sometime on Sunday (April 15) with precipitation possible through about April 17-18.

The upshot of the storms on April 12-13 and April 15-18 is that they should be colder than our current storm, so most elevations will get snow and not rain.

Thanks for reading!

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