Bollettino valanghe

Logan

Utah Avalanche Center
Vedi sulla mappa

Pericolo valanghe

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco
Non aggiornato — questo bollettino è scaduto 6 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Heightened avalanche conditions and MODERATE danger exist at mid and upper elevations in the backcountry. People could trigger dangerous 1 to 3 feet thick slab avalanches failing on a sugary persistent weak layer. Avalanches could be triggered remotely or from a distance. You can find safer conditions and pretty nice snow in sheltered terrain and on lower angled slopes. There is very little snow at many trail heads and LOW danger, with avalanches unlikely on most lower elevation slopes.

  • Shallow snow coverage dictates careful travel, and hitting rocks and other obstacles still presents a serious risk in the backcountry.
  • Cracking and collapsing indicate unstable snow.
  • Evaluate snow and terrain carefully, and continue to stay off and out from under steep drifted slopes.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    3

    Many slopes in the region are plagued by layers of weak faceted snow formed during the prolonged November dry spell. Avalanches failing on a persistent weak layer can be very sensitive, and they might be triggered remotely, from a distance, or worse from below!

    Observers continue to report triggering booming audible collapses in many areas. These whumpfing sounds are a red flag indicating unstable snow, telling us that dangerous avalanche conditions exist. Here is a video observation from 12-27-2020,

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2

    Drifting of Sunday's fresh snow from strong east winds Monday built stiffer drifts and wind slabs in unusual or perhaps unexpected places, and human triggered avalanches of wind drifted snow are possible on slopes at mid and upper elevations facing any direction. These will most likely be found near ridge tops and in and around terrain features like gullies, cliff bands, and sub ridges.

    People could trigger 1 to 3 feet thick slab avalanches of wind drifted snow on steep slopes, especially where drifts formed on weak, sugary, or faceted snow. Soft drifts of newer snow, up to about a foot deep, could be quite sensitive, and some may be triggered remotely or from a distance. Harder wind slabs may allow people to get out on them before releasing.

    • Even a small avalanche could be very dangerous due to shallow early season snow conditions.

Recent Activity

A couple large natural avalanches occurred with last weekend's small but windy storm.

  • A large natural avalanche of wind drifted snow, 2 feet deep and at least 500' wide, was spotted on the corniced east ridge of Chicken Hill in Bunch Grass.

This broad natural avalanche in Grandfather Cornice on Cornice Ridge occurred at about 9200' on a northeast facing slope.

Additional Info

Everybody should make time to examine and practice with your avalanche rescue equipment, and convince your backcountry partners to practice with you. Watch our companion rescue video HERE My tip for avoiding avalanches in the backcountry is to keep your slope angles low. Avoid and stay out from under slopes steeper than about 30 degrees. Get a tool to measure slope angle and practice with it in the backcountry. Watch the video HERE.

Paige shows what we are talking about when we mention faceted snow in our forecasts. Watch the video HERE

Snow and Weather

Lower angled slopes in sheltered terrain offer nice conditions in fast, shallow powder. On steeper slopes you will still sink into the underlying sugary older snow, and you could trigger dangerous avalanches on steep drifted slopes. Snow coverage is still very shallow in the Logan Zone, and the snow that was on the ground in November and early December is very loose and sugary. In many places you still sink all the way to the ground when you hop off your sled or come out of your skis.

There are lots of shallowly buried land mines out there, and you risk more than just a little sled damage riding in steep terrain right now.

It will be mostly sunny today with 8500' high temperatures in the mid twenties, breezy, with north winds in the morning veering from the west in the afternoon. Wind chill values will be around -4° F. A series of weak weather systems will cross the area this weekend, with little in the way of accumulation. A potentially stronger system is expected Monday night and Tuesday.

Special Announcement

We are offering a Backcountry 101 Avalanche education class in Logan on Jan 21 and 22. . Details and registration here.

Check out our new and relevant Blog featuring Paige and Greg discussing Danger Ratings and Persistent Weak Layers....HERE

Thanks to the generous support of our local resorts, Ski Utah, and Backcountry, discount lift tickets are now available. Support the UAC while you ski at the resorts this season. Tickets are available here.

General Announcements

Visit this website with information about Responsible Winter Recreation by the Utah Office of Outdoor Recreation.

We've kicked off Season 4 of the UAC podcast with a Conversation with American Avalanche Institute owner Sarah Carpenter. You can stream it HERE or wherever you get your favorite podcasts.

The Tony Grove Road is not maintained for wheeled vehicles in the winter.

EMAIL ADVISORY. If you would like to get the daily advisory by email you subscribe HERE.

Remember your information can save lives. If you see anything we should know about, please help us out by submitting snow and avalanche observations....HERE. You can also call us at 801-524-5304, email by clickingHERE, or include #utavy in your tweet or Instagram.

I will update this forecast by around 7:30 tomorrow morning.

This forecast is from the USDA Forest Service, which is solely responsible for its content. The forecast describes general avalanche conditions and local variations always occur.

Regioni coperte