Boletín de aludes

Logan

Utah Avalanche Center
Ver en el mapa

Peligro de aludes

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque
Open full map
Desactualizado: este boletín caducó 8 years ago. Estás viendo condiciones pasadas, no el boletín vigente.

Lo esencial

MODERATE: Heightened avalanche conditions exist on drifted upper elevation slopes, and you could trigger avalanches involving fresh wind-drifted snow. More dangerous but less likely hard slab avalanches failing on a buried sugary persistent weak layer remain possible. It will be wicked cold in the mountains today, but you'll find nice shallow powder, mostly stable snow, and generally LOW danger in sheltered terrain and on lower and mid-elevation slopes.

Evaluate snow and terrain carefully.

Problemas de aludes

  • Wind Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    2

    Heightened avalanche conditions exist on upper elevation slopes, and you could trigger avalanches consisting of wind drifted snow. The light snow from yesterday and overnight was easily drifted by last night's westerly wind, and the fresh drifts are likely to be sensitive to human triggering today. Drifting occurred in exposed terrain much of the week, and there are some deeper hard wind slabs lurking under the fresh snow in places.

    • Watch for and avoid fresh or older drifts on the lee sides of major ridges and in and around terrain features like cliff bands, scoops, gullies, stringers, and sub-ridges.
    • Avoid steep slopes that have a smooth, rounded appearance, or that sound hollow like a drum.
    • Hard wind slabs have a nasty tendency to let you get well out on them before releasing.
    • Cracking in the snow is a red flag indicating potential instability.

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Unlikely
    Tamaño
    3

    A shallowly buried layer of sugary faceted snow called near surface facets was buried by last week's storm and it could become active on some drifted slopes. Although rather unlikely, dangerous human triggered hard slab avalanches failing on a persistent weak layer near the ground called depth hoar are still possible on upper elevation slopes with poor snow structure.

    The shallow snow on the ground in many areas has become loose, sugary, and faceted in the past couple weeks. I found particularly weak snow in the backcountry near Beaver Mountain, where the total snow is only about 2-feet-deep or less. In these areas the snow is currently stable despite it's weakness, but it'll get interesting when we get significant accumulation in the future.

    • Collapsing and cracking indicate that snow is unstable.

    • Avoid steep shady or rocky terrain at upper elevations.

    Sugary, faceted snow from the Thanksgiving storm creates a persistent weak layer near the ground on slopes with shallow snow cover. This from 12/20/18, on a west facing slope at 8500' on Beaver Mountain's backside.

Recent Activity

Looking west from Mendon Thursday morning we noticed some natural avalanche activity due to wind drifted snow on steep slopes near the ridge in the Wellsville Mountain Wilderness.

Snow and Weather

A few inches of light snow fell in the Logan Zone yesterday and overnight, enough to refresh the wind hammered snow surface and whiten things up a bit. But, not enough to change the avalanche danger much, and you'll find nice shallow powder, stable snow, and Low avalanche danger in most areas. Exceptions will be on drifted upper elevation slopes where human triggered slab avalanches involving fresh wind drifted snow are possible. Today will be wicked cold and a bit blustery in the mountains, so watch exposed skin on your partners for potential frost bite. You can find good access and pretty good coverage for this time of year, but the snow is still just a bit too shallow to ride in steep terrain or to get aggressive with your throttle.

West and southwest winds raked the mountains in the Logan Zone last week, but a few inches of nice light snow yesterday and overnight will make for nice shallow powder conditions in the backcountry today.

Temperatures plummeted overnight in the Bear River Range, and it will be quite cold today. The Tony Grove Snotel at 8400' reports 11º F this morning and 4 inches of light new snow with .2" SWE. There's 37"of total snow, containing 87% of average SWE for the date. It's a chilly 4º F at the 9700' CSI Logan Peak weather station, with 25 mph northwest wind, gusting into the upper 30s.

An active weather pattern will continue for Utah through the next week with several storms expected to impact the state through Christmas Day. We'll see mostly sunny skies in the mountains today, with a high temperature at 8500' near 20º F, west wind 10 to 18 mph, and wind chill values as low as -11. Increasing clouds tonight will moderate the cold a bit and temperatures will rise from a low of around 8º F to near 20º F by tomorrow morning. 10 mph westerly wind will veer from the southeast in the evening. Expect mostly cloudy conditions tomorrow and a good chance of snow, a high temperature of 28º F, and southwest winds 15 to 25 mph.

Additional Info

I will update this advisory Monday morning.

General Announcements

The new UAC IOS mobile app is now available on the app store. Check out the new "My Weather" feature. HERE

Check out the new free online avalanche course series developed by the Utah Avalanche Center. This is a great way to refresh your skills or prepare you for a Backcountry 101 or Level 1 class. HERE

Now is a great time to practice companion rescue techniques with your backcountry partners. Here is our practice video.

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

Support the UAC through your daily shopping. When you shop at Smith's, or online at REI, Backcountry.com, Patagonia, NRS, Amazon, eBay by clicking on these links, they donate a portion of your purchase to the UAC. If you sell on eBay, you can have your See our Affiliate Page for more details on how you can support the UAC when you shop 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 call us at 801-524-5304, email by clicking HERE, or include #utavy in your Instagram.

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.

Regiones cubiertas