Looking back at the past storm

Before getting to the forecast, I want to look back at the storm on Sunday night and Monday morning.

Going into that system, I thought that most mountains would be in the 4-8 inch range, with a few spots pushing double digits, and that this deeper snowfall would occur at areas favored by northwest flow on the backside of the storm, including Telluride/Silverton in the southern mountains, Aspen Highlands in the central mountains, and areas along the I-70 corridor from Vail east to Breckenridge, Loveland, and Winter Park.

The reality was that the average for most mountains was in the 4-8 inch range. That forecast turned out OK.

In the southern mountains, Telluride picked up 12 inches. That forecast turned out OK.

In the central mountains, Aspen Highlands only picked up 3 inches. My forecast was wrong.

In the northern mountains, most of the I-70 corridor was in the 4-8 inch range, but the only bigger total was at Winter Park.

Speaking of Winter Park, their snow stake camera at mid-mountain showed a storm total of 14 inches, and only 4.5 miles away and about 1,000 feet higher, Berthoud Pass only received 6-7 inches. I cannot explain why Winter Park received double the snow as nearby Berthoud Pass. Usually, the two locations are similar, and the Pass often has more snow.

In the far north, the winner of this storm was Steamboat with 17 inches at the summit snow stake. Their wind direction didn’t blow from the northwest, as most large-scale models suggested, but instead blew from the west, which is the better direction for deeper snow at Steamboat. Also, the Tower SNOTEL site, 6.5 miles to the north-northeast of Steamboat, only recorded about 7 inches, roughly half of what the summit of Steamboat received. Usually, this is the opposite, with the Tower SNOTEL site recording about double the amount of snow at Steamboat. Again, I cannot explain why this happened.

The bummer for me is that, since I cannot figure out why some of these surprisingly high snow totals occurred, I likely won’t be able to forecast them next time. So, while the forecast for the storm was reasonable – Monday would be the best powder day, with 4-8 inches across the state and some double-digit totals – I want to figure out how to forecast the higher totals, and just can’t explain it this time. If any of you have evidence-based theories, email me and lets chat ([email protected])! Also, snow stake cameras are fantastic. Even if the forecast doesn’t perfectly capture the details of the storm, you can always wake up early, look at the cameras, and chase to the deepest snow.

Looking ahead

On Monday night and Tuesday morning, pieces of energy and moisture are still streaming over the northern mountains, and this has created pockets of light snow with 1-2 inches accumulating overnight for areas near and north of I-70. You can see clouds (blue colors) continuing to flow over northern Colorado on the satellite image below.

We should see a similar pattern on Tuesday and Tuesday night with some clouds and times of light snow over the northern mountains while the rest of the state is mostly dry.

Then on Wednesday and Thursday, we’ll have warmer temperatures and likely dry weather most of the time. We could see an early surge of moisture and energy from the southwest which could push a few showers over the state, though I don’t think we’ll see meaningful accumulations.

Steady precipitation will then arrive on Thursday night or Friday morning and continue through Friday night. The beginning of this storm will be warm with a freezing level averaging around 10,000 feet. The image below shows the temperature forecast on Friday midday at about 10,000 feet, given in degrees Celsius (0C = 32F).

The warmest temperatures will be early in the storm, on Thursday night through the first half of Friday. While the freezing level will average around 10,000 feet, the snow level is different as intense precipitation can lower the elevation at which you’ll find snow. During the most intense precipitation, the snow level could lower to 8,500 feet or so, and then during lighter precipitation, it could climb back toward 10,000 feet.

If you want to ski on Friday, seek the higher-elevation ski areas with bases above 9,000 feet. Also, with a wind direction from the southwest and west-southwest, the most orographically favored locations for deeper snow will be Wolf Creek, Silverton, Crested Butte, Monarch, and potentially Summit County later in the day.

Cooler air will move in on Friday night with at least a few inches of snow after lifts close on Friday, so Saturday morning might be my pick for the best powder as you’ll have colder snow on top of the dense snow from Friday. Average snow amounts should be in the 4-8 inch range, with lower amounts at the lower-elevation ski areas and higher mountains at the highest elevations. Again, elevation will be key on Friday! Also, since we'll have a LOT of moisture with this storm, we could see higher than expected snow totals at a few higher-elevation mountains because moisture is the fuel for snow.

Following the Friday and Friday night system, we might see a break in the action on Saturday and Sunday. The latest models keep the center of the trough (area of storminess) to the west of Colorado through the weekend. You can see this trough as the lines that dip to the south, centered over Utah, just west of Colorado.

If this forecast verifies, following a mostly dry weekend, we could have chances for snow during many days next week as that area of storminess stalls over or near Colorado. Some models favor the most snow next week to fall near and east of the divide, but we’re still about a week away from this happening, so no sense in spending too much time with the details, as they will change.

Thanks for reading!

JOEL GRATZ

Powderhorn Mission Affordable
Skiing is expensive, so it’s nice to see that there are some deals to be had. Powderhorn just released pricing for next season’s pass (which also works for the rest of this season). Details here: http://opsw.co/2FPVLAY

Child Pass (5 & under), $29
Junior Pass (6-12), $149
Young Adult Pass (13-29), $259
Adult Pass (30-74), $259
Senior Pass (75+), $89

Eagle Point, Utah
Evan, our Utah forecaster, mentioned this week that Eagle Point in Utah, which couldn’t open for a lot of this season due to low snow, is offering current pass holders a free pass for next season. Awesome. Details here: http://opsw.co/2HJaRc5

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