Avalanche Advisory
Advisory: Uintas Area Mountains Issued by Craig Gordon for Sunday - January 28, 2018 - 4:04am
bottom line

While not widespread and limited to terrain in the wind zone at and above treeline, the avalanche danger is CONSIDERABLE. Human triggered avalanches are likely on steep, wind drifted slopes, especially those facing the north half of the compass and particularly those with an easterly component to their aspect. Once triggered, today's avalanches can quickly get out of hand if they break into weak layers of snow now buried several feet deep in our snowpack.

Mid elevation terrain offers MODERATE avalanche danger and human triggered avalanches are possible on steep leeward slopes with recent deposits of wind drifted snow.

Most wind sheltered mid and low elevation terrain, especially south facing slopes offer generally LOW avalanche danger.
current conditions

High clouds drifted into the area late yesterday, decided to spend the night, keeping temperatures relatively warm and in the mid teens and 20's. After a brief dinner break, south and southwest winds bumped into the 20's and 30's along the high ridges. Thursday night's little storm delivered 7" of light, white, chin tickling goodness. And while recent winds blasted our big open bowls, soft settled snow is found on wind sheltered, mid elevation, shady terrain.

Above are 24 hour temperatures and snow depth from Trial Lake along with winds and temperatures from Windy Peak. More remote Uinta weather stations are found here

One of JG's beautifully detailed pit profiles from Weber Canyon. Here's his takaway.... "Today's test were failing about 66 cms down (26") on 1-2mm faceted grains. The shears were clean and energetic and failing with medium to hard effort. Full, energetic propagation on ECT's." Killer insight from a very experienced avalanche professional. There's also a great body of recent trip reports, observations, and snow data found here.


recent activity

The avalanches above from Weber Canyon and Chalk Creek reported to us on Saturday are what we call persistent slabs. They were triggered remotely, from a distance. And nope... you don't have to be climbing to kick the legs out from underneath it. Click here to see how this slab is reacting to our additional weight.

In addition, my colleagues posted a great, detailed investigation of the Silver Fork Meadows Chutes accident from Friday and that's found HERE. Even though it's a different mountain range, it a solid read and there's lots of similarities to what's going on with our snowpack.
Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

Since Thursday night, west and southwest winds have been blowing in the 30's and 40's, forming fresh drifts in upper elevation terrain. Found mostly on the leeward side of upper elevation ridges, I bet a rogue drift or two still lurks around a terrain feature like a chute or gully wall. In either case, today you'll want to look for and avoid any fat, rounded piece of snow, especially if it sounds hollow like a drum.

Ted was stomping around Moffit Peak yesterday and his images clearly illustrate winds have been busy at work. The top picture shows winds blowing right to left, stripping snow near the ridges and depositing that snow on the leeward side (bottom picture), forming slabs sensitive to our additional weight. (Scroggin photos)
Avalanche Problem 2
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

Once triggered, like the slab above from midweek, an avalanche breaking into weak layers of snow now buried in our midpack, will quickly get out of hand and instantly ruin our day. The most likely suspects are steep, rocky, wind drifted slopes facing north half of the compass. Since this avalanche dragon is unpredictable, the best offense is a good defense... you simply avoid it. Swing around to lower elevation south facing slopes or choose low angle terrain with no steep slopes above or adjacent to the slopes your riding. (Kikkert photo)
weather

A weak weather disturbance brushes by the area bringing a slight chance of light snow this morning. High temperatures reach into the low 30's with overnight lows dipping into the 20's. West and northwest winds are gonna be a nuisance, ramping up later this morning and blowing in the 40's and 50's along the high peaks. High pressure strengthens tonight, remaining in place for Monday and Tuesday, bringing a warming trend to the region.
general announcements

The information in this advisory expires 24 hours after the date and time posted, but will be updated by 7:00 AM Monday January 29, 2018.

If you're getting out and about, please let me know what you're seeing especially if you see or trigger and avalanche. I can be reached at [email protected] or 801-231-2170

It's also a good time to set up one of our very popular avalanche awareness classes. Reach out to me and I'll make it happen.

This information does not apply to developed ski areas or highways where avalanche control is normally done. This advisory is from the U.S.D.A. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.