Issued by Toby Weed on Friday morning, March 11, 2022
Avalanche accidents are likely in the backcountry this weekend! Heavy snow and drifting overloaded slopes with a buried persistent weak layer and created dangerous avalanche conditions in some areas.Areas with CONSIDERABLE danger exist on upper and mid elevation slopes facing northwest, north, and northeast. People who venture into this avalanche terrain are likely trigger dangerous 1 to 3 foot deep slab avalanches failing on a buried layer of faceted snow. Human triggered wind slab and dry or moist loose avalanches of storm snow are possible at all elevations in steep terrain.
Continue to avoid and stay out from under drifted slopes steeper than 30°, especially those facing the north half of the compass.
Careful snowpack evaluation, cautious route-finding, and conservative decision making are essential.
Head's up! Need a refill for your airbag canister? Arva and Al's will be doing a one night “Free Refills” for any brand of refillable air canister on Friday, March 11 from 6-8PM. Canisters can be dropped off before the event also.
Thanks to the generous support of our local resorts and Ski Utah, discount lift tickets are now available. Support the UAC while you ski at the resorts this season. Tickets are available HERE.
Weather and Snow
Very nice powder conditions exist in the backcountry, and you can find nice riding on slopes at all elevations, even on sunny slopes. During the week, copious heavy snow and drifting from fairly strong west winds overloaded slopes with buried persistent weak layers consisting of sugary faceted snow. Natural avalanches were common across the Logan Zone during the storm, and dangerous avalanche conditions persist on many slopes facing the northern half of the compass. People could trigger dangerous avalanches this weekend if they venture into steep north facing terrain.
At last we found very nice powder riding conditions in the Central Bear River Range backcountry yesterday.
The 8400' Tony Grove Snotel reports 11°F this morning, and there is 77 inches of total snow at the site, with 86% of normal SWE for the date. The storm total from this week's storm was around 20 inches, with 1.9" SWE. Winds out of the west-northwest increased overnight and are blowing about 25 mph at the 9700' CSI Logan Peak weather station. With plenty of nice powder to blow around at upper elevations, the westerly winds will drift snow into avalanche starting zones creating fresh wind slabs and continuing to load suspect slopes with poor snow structure.
It will be nice, pretty cold, and sunny today in the mountains. Expect high temperatures at 8500' around 19°F, with 11 to 18 mph west winds pushing wind chill values around -12°F. Keep in mind that these very cold temperatures add a level of risk and make everything, including rescue operations, more difficult.
Expect partly cloudy skies tonight, with temperatures rising to around 17°F, and with 13 to 17 mph wind from the west, wind chill values will be as low as -6°F.
Nice, mostly sunny cold weather is expected tomorrow, with a high temperature around 30°F and 13 to 17 mph west-southwest winds.
There is a good chance for some snow on Sunday, with 2 to 4 inches of accumulation possible.
Recent Avalanches
Natural avalanches were common in the Logan Zone during this week's storm, with evidence of some fairly large avalanches visible yesterday with clearing.
Riders triggered a couple small slab avalanches in the Central Bear River Range yesterday.
Parties in the Logan Zone reported numerous red flags in the backcountry this week, including audible collapsing and cracking in some areas.
A skier triggered a scary slab avalanche that failed on a sugary persistent weak layer Tuesday evening in the the Dog Leg avalanche path in Providence Canyon.
Yesterday, we observed lots of natural activity including a couple good sized natural avalanches in the Wellsville Mountain Wilderness, which were quite visible from Cache Valley.
Riders triggered this small slab avalanche yesterday in Christmas Tree Bowl, just north of Naomi Peak.
As the storm came in Tuesday afternoon, a skier triggered this impressive soft slab avalanche that failed on a buried persistent weak layer in Provudence Canyon.
Check out all the recent backcountry observations and many recent avalanche reports from across Utah HERE
Avalanche Problem #1
Persistent Weak Layer
Type
Location
Likelihood
Size
Description
The fresh snow is creating a more cohesive slab on widespread preexisting layers of very weak faceted snow. In many areas the overload of heavy new snow could be enough to activate these layers and cause dangerous slab avalanches. On slopes facing the north half of the compass, people are likely to trigger soft slab avalanches failing on a buried persistent weak layer. Red flags of snow instability are apparent in the backcountry, avalanches have been observed locally, and we've received reports of extensive audible collapses and cracking.
Avalanches could be triggered remotely or from a distance.
Collapsing and cracking are red flags indicating unstable snow and a persistent weak layer.
Avalanche Problem #2
New Snow
Type
Location
Likelihood
Size
Description
Small soft slab and loose avalanches of storm snow are likely for people to trigger on slopes steeper than 30° at all elevations today.
Loose dry avalanches(or sluffs) of fresh snow are likely in sheltered terrain at all elevations on very steep slopes. Despite the cold, when the intense March sun pops out, it could moisten the fresh snow surface and it could make the snow sticky and prone to sluffing. On sustained slopes, sluffs could pile up deeply, especially in terrain traps like gullies, sinks, and benches.
Manage loose avalanches by staying out of constricting terrain, like drainage gullies, and moving out of the fall line so you don't get caught by your own sluff.
Avoid being caught and pulled into terrain traps below you like trees, gullies, sinks, or benches.
Avalanche Problem #3
Wind Drifted Snow
Type
Location
Likelihood
Size
Description
West-northwest winds increased overnight, and there is plenty of nice powder to drift about. Westerly winds during the storm were plenty strong enough to create significant drifts and soft slabs up to a couple feet deep, and fresh drifts formed overnight and will continue building today. Drifting is overloading slopes with buried persistent weak layers and increasing the depth and weight of a developing slab layer. Avalanches of wind drifted snow are possible on slopes at all elevations, but are most likely at upper elevations on northeast, east, and southeast facing slopes.
Avoid fresh drifts on the lee side of major ridges and in and around terrain features like around and below cliff bands, gully walls, and sub-ridges.
Additional Information
Now is a great time to practice your avalanche rescue skills. Thanks to the generous support of Northstar, the Franklin Basin Beacon Training Park is up and running. The park is located directly west of the parking lot and is open for anyone to use. All you need is your beacon and probe. Please do not dig up the transmitters.
Always follow safe backcountry travel protocols. Go one person at a time in avalanche terrain, while the rest of your party watches from a safe area. (practice anytime while traveling on or under backcountry slopes steeper than 30°)
Check your avalanche rescue equipment, change your batteries, and practice often with your backcountry partners.
Check slope angles, and to avoid avalanche terrain stay off of and out from under slopes steeper than 30° and adjacent slopes. Video Here
General Announcements
Special thank you to Polaris and Northstar...Video Here
Who's up for some free avalanche training? Get a refresher, become better prepared for an upcoming avalanche class, or just boost your skills. Go to https://learn.kbyg.org/ and scroll down to Step 2 for a series of interactive online avalanche courses produced by the UAC.
Check out all the upcoming education classes and clinics HERE.
Please submit your observations from the backcountry HERE.
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.
