Bulletin d’avalanche

Salt Lake

Émis le Feb 22, 2025valide jusqu’au Feb 23, 2025Utah Avalanche Center

Danger d’avalanche

Alpin
Limite forestière
Sous la limite forestière

Périmé — ce bulletin a expiré 2 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

The avalanche danger is CONSIDERABLE on slopes at the mid and upper elevations facing west, northwest, north, northeast, east, and southeast. Here, slab avalanches may break down several feet deep into weaker layers in the snowpack. These are tricky and dangerous conditions that require careful and continual evaluation of the snowpack and terrain.

Wet-loose avalanches on steep, southerly-facing slopes are possible with daytime heating and direct sun.

Problèmes avalancheux

Persistent Slabs
N
NE
E
SE
S
SW
W
NW
Alpin
Limite forestière
Sous la limite forestière
Probabilité
Likely
Taille
3
There are four distinct persistent weak layers:

Old-faceted snow near the base of the snowpack. This layer is more pronounced in shallow snowpack areas (less than 4 feet deep) or steep rocky terrain.

Repeater slopes. Meaning slopes that have previously avalanched one or more times this season.

Late January facets are found on many aspects.

Facet/crust combos on solar slopes, including low- and mid-elevation southeast-facing terrain.

Truth be told. Days like today are when we see many accidents happen. It's the second sunny day after a large storm that loaded many weak layers in the snowpack. Telltale signs like cracking and collapsing will not be on your face and you'll see riders testing slopes. It's easy to think it is stable once we've seen tracks. I've seen slopes with 1/10/20/30/40/100 tracks on them before the slab releases taking out all the tracks on the slope. In the coming days, the likelihood of triggering an avalanche is decreasing. However, these slab avalanches will remain deadly if you trigger one.

Think about your backcountry career. You ride 25 days a winter. Each day, the average human makes about 35,000 choices. Now, let us do some math: 35,000 choices X 25 days X 30 years = 26,250,000 times you need to make the right choices throughout your day. I've thought about this a lot being a career avalanche forecaster. You only get a couple of chances in the mountains. Unfortunately, some of us won't get a second chance.
Storm Slabs
N
NE
E
SE
S
SW
W
NW
Alpin
Limite forestière
Sous la limite forestière
Probabilité
Possible
Taille
2
You may find sensitive soft slabs failing within the new snow. Perform shovel tilt tests and use slope cuts to see how the new snow is stabilizing. Also, watch for pockets of wind-drifted snow across the upper elevations.
Loose Wet
N
NE
E
SE
S
SW
W
NW
Alpin
Limite forestière
Sous la limite forestière
Probabilité
Possible
Taille
2
It's closer to March than February. The sun is strong this time of year and it doesn't take much to turn cold snow into damp/wet snow. Be on the lookout for signs of wet snow avalanches. If you're seeing roller balls it's time to change to a cooler aspect. When I hear in the forecast that we could have mid to high-level clouds, "green housing" starts to come to mind. Be on the lookout for snow on the shady aspects also becoming wet or damp with daytime heating.

Special Avalanche Bulletin

The Utah Avalanche Center is issuing a Special Avalanche Bulletin after a series of storms in the last week has left a thick blanket of snow at all elevations, creating excellent powder riding conditions while also elevating the backcountry avalanche danger. Don't let the fresh snow and sunshine influence your decision-making - avalanche conditions remain dangerous, and careful snowpack and terrain analysis are required for backcountry travel. Fortunately, there are great riding and travel conditions away from avalanche terrain on slopes less than 30° in steepness.

Special Announcement

Please respect the Utah Department of Transportation's backcountry closures. They aren't shutting down the backcountry to save powder for themselves. They watch every aspect of the Cottonwood Canyons to make sure we can drive up and down safely.

Recent Activity

Yesterday, backcountry riders could see the destruction from this past week's avalanche cycle. Many large avalanches were reported. We also saw a widespread wet-loose avalanche cycle on steep solar aspects yesterday. Some of these avalanches started in dry snow, but by the time they got to the bottom, they were wet and large enough to bury a human. Be sure to check out all the observations HERE.

Photo: Wasatch Powderbirds showing a recent slab avalanche in the Hallway.

Snow and Weather

Under mostly clear skies, the mountain temperatures are inverted. Trailheads are in the single digits, while upper elevations are in the upper teens to low 20s Fahrenheit. The wind is relatively calm across most terrain, blowing 5-15 mph from the west-northwest. However, closer to 11,000' the wind is blowing a bit stronger at speeds of 20-25 mph. Today, we expect increasing cloud cover and temperatures rising into the upper 20s to low 30s °F. The wind is forecast to stay about the same, blowing 5-15 mph across most upper elevations. Riding and turning conditions are as good as they get... for this year anyway. Yesterday, the sun came out and this morning you will find a zipper crust on most south through west-facing terrain. Soft-settled powder exists on many of the shady aspects. Extended snow forecast: Not good!

Additional Info

Be sure to read Nikki's Week in Review as you make your backcountry travel plans.

General Announcements

CLICK HERE FOR MORE GENERAL INFO AND FAQ

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

Observations and Avalanches

Backcountry Emergency Procedures