Logan Avalanche Advisory

Forecaster: Toby Weed


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

Danger Rose Tutorial

A CONSIDERABLE (level 3) avalanche danger remains in the backcountry, and dangerous avalanche conditions exist on most shady slopes above around 7500' in elevation. In these areas, human-triggered avalanches continue to be very likely on slopes steeper than about 35 degrees. Avalanches this weekend could be triggered remotely from a distance or from below, so we need stay off and out from under steep slopes and avalanche paths...

Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential for safe backcountry travel today.


Dangerous avalanche conditions continue to plague upper elevation slopes in the region that did not avalanche during last weekend's storm...Most folks are wisely playing it safe locally, and there are lots and lots of steep suspect slopes that remain untracked and untested in the region...You can find safer conditions at lower elevations and on sunny slopes that didn't have much or any soft snow on the ground before last weekend's storm.

This morning, the Tony Grove Snotel reports an air temperature of 20 degrees, with 31 inches of total snow containing 5.5 inches of water equivalent. This gives the 8400’ weather station 52% of average snow for the date. Its 18 degrees at 9700’ on Logan Peak, and the Campbell Scientific weather station reports a light northerly breeze….


Yesterday afternoon, we were heading back down to Tony Grove Lake after a nice day on south facing slopes in the Mt. Naomi Wilderness. We chose to stay on the ridge and on fairly low angled terrain in route down due to our fear of unstable snow conditions….Darren led our well spread-out group of four of us down the ridge, and he heard and felt a large whumpf or collapse…The second member of our party saw the slope shatter about 150 feet in front and below Darren, and watched as a large remotely triggered avalanche ran violently into the flats below the bowl. Nearly a week after a storm dumped a heavy load of snow onto our weak snowpack, we'd just triggered a large and dangerous avalanche, thankfully from a distance. (Tony Grove-Blind Hollow Saddle,12-18-09)

This brings the string of days with tricky and dangerous unintentionally triggered avalanches in the Utah Mountains up to at least 6 straight.....(current conditions page)

A widespread natural avalanche cycle occurred region-wide on Sunday 12-13-09 with large and scary natural avalanches.......One party reported remotely triggering a couple avalanches near Tony Grove Campground...(12-14-09 photos)...

The weakness and poor structure of an unstable snowpack persist, and again yesterday we noted widespread and extensive triggered audible collapses… Snow stability tests continue to show a widespread, scary weakness and propagation tendency.... (Holiday Bowl 12-17-09)


      Over the next 24 hours.

Very weak faceted snow plagues most shady upper and mid elevation slopes, and new slabs built on top of this by significant heavy snow last weekend caused a very unstable snow structure. This is a persistent and very dangerous problem, and a great danger of triggering deadly avalanches remains... As we've seen, in these conditions avalanches can easily be triggered remotely from a distance, or worse from below.

Its certainly not the weekend to be pushing your luck, and I urge you to refrain from hill climbing or center punching slopes in any avalanche prone terrain, (specifically, mid and upper elevation shady slopes with preexisting snow.)


Looks like continued benign weather, with a ridge of high pressure system strengthening through the weekend.... Expect mostly cloudy conditions today with a chance of a little light snow and high temperatures near 25 degrees today in the mountains with a developing light south west breeze....Sunday will be similar; a chance of a little light snow with a little stronger southwest wind and mountain temperatures rising to around freezing.

Our next chance for more accumulating snow comes early next week, (Monday night-Tuesday). Model inconsistency spells uncertainty as to location and timing of this, but a low pressure trough will take control of the weather over the region, hopefully putting an end to the smog trapped in the Cache and good chance for snow in the mountains…


I will be issuing morning avalanche advisories for the Logan area on Mondays, Wednesdays, Fridays and Saturdays.

Discount Lift tickets: Ski Utah, Backcountry.com, Alta, Deer Valley, Park City, The Canyons, Wolf Mountain, Snowbasin, Beaver Mountain, Brighton, Sundance, and Solitude have donated a limited number of tickets for sale at discounted prices.

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Send us your avalanche and snow observations. You can also call 435-755-3638 or 800-662-4140, or email to uac@utahavalanchecenter.org

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The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.

I will update this forecast on Monday morning. Thanks for checking in....

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.