Logan Avalanche Advisory

Forecaster: Toby Weed

BOTTOM LINE

Danger by aspect and elevation on slopes approaching 35° or steeper.
(click HERE for tomorrow's danger rating)


Danger Rose Tutorial

There is a Level 1 or Low danger on most slopes in the region, and avalanches are generally unlikely. However, pockets with heightened avalanche conditions still exist on some steep drifted slopes, mainly at upper elevations.. In these areas there are pockets with a level 2 or Moderate danger and you might trigger wind slab avalanches. Generally safe avalanche conditions exist in most areas, but you should watch out for unstable stiff wind slabs in exposed upper elevation terrain...


CURRENT CONDITIONS

The Tony Grove Snotel at 8400' reports 14 degrees this morning, and there is 31 inches of total snow on the ground.. It's 15 degrees at the 9700' CSI Logan Peak weather station, and the station is recording average 20 mph northwest winds. You'll find generally shallow coverage and boney snow conditions in the backcountry.. In some areas that were fairly supportable last week, you now bog down into weak sugary facets.... The strength of the snowpack is noticeably deteriorating with this clear cold weather, and we are set up for dangerous avalanche conditions when the inevitable snow finally comes....


RECENT ACTIVITY

No new avalanches were reported from over the weekend.. We are monitoring the current shallow snowpack as high pressure conditions and cold air temperatures are causing it to weaken significantly. Since the snow is shallow in many areas, it is subjected to an extreme temperature gradient when the air temperature is cold. A temperature gradient drives sublimation of water vapor through the snowpack, which transforms the snow crystals into weak sugary non-cohesive grains called facets. We need snow, but unfortunately when we get a significant dump we'll be cursed by dangerous persistent weak layers that are forming now....


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 12 hours.

Watch for stiff wind slabs in exposed terrain. Avoid rounded, chalky looking, or hollow sounding drifts on steep slopes near ridgelines and in and around terrain features... Wind slabs formed in somewhat unusual places due to the recent easterly wind events...


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Loose dry surface sluffs involving weak surface snow are becoming more common in the mountains across northern Utah, and I expect some slopes in the Logan Area are prone to this issue.....Also still be especially wary in drifted rocky or shallow areas that held October snow before the big mid November storms. Although fairly unlikely these days, you might trigger a dangerous avalanche running on weak basal snow from an area where the slab is thinner and more reactive to your weight. Obviously, the consequence of being caught in an early season avalanche is greatly increased by the shallowly buried and exposed rocks you could be raked over...


MOUNTAIN WEATHER

Expect another chilly but fair day in the mountains today, with a westerly breeze and high temperatures just a few degrees warmer than yesterday reaching around 24 degrees. A weak cold front is forecast to swing through the region tomorrow bringing some cloudiness and a little hope of clearing the stale air out of the valleys. But, at this point it doesn't look like it'll produce much if any snow before the high pressure builds back into the area and controls the weather pattern through the coming weekend.


GENERAL ANNOUNCEMENTS

The Friends of the Utah Avalanche Center in Logan is offering a Backcountry 101 class next weekend... The class starts with a classroom session on Friday evening, and includes a field day in the backcountry on Saturday. click HERE for more details....

Thanks to all who attended, donated, and helped to put on our annual fundraiser party Wednesday night. It was a big success thanks to you!

You have the opportunity to participate in the creation of our own community avalanche advisory by submitting avalanche and snow observations. You can also call us at 435-757-7578 or 801-524-5304 or email by clicking HERE

Donate to your favorite non-profit – The Friends of the Utah Avalanche Center. The UAC depends on contributions from users like you to support our work.

I will update this advisory by around 7:30 in the morning on Mondays, Wednesdays, Fridays, and Saturdays.....

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.


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.


This advisory provided by the USDA Forest Service, in partnership with:

The Friends of the Utah Avalanche Center, Utah Division of State Parks and Recreation, Utah Division of Emergency Management, Salt Lake County, Salt Lake Unified Fire Authority and the friends of the La Sal Avalanche Center. See our Sponsors Page for a complete list.