Wasatch-Cache National Forest  In partnership with:  Utah State Parks and Recreation, Friends of the Utah Avalanche Center-Logan, and Utah State University College of Natural Resources.

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Logan area Avalanche advisory

Special Update

 December 14, 2006

Hello and good morning, this is Toby Weed of the Utah Avalanche Center in Logan with a special update  of your backcountry avalanche and mountain weather advisory.  It's Thursday December 14th, and it's 7:00 in the morning. This advisory is brought to you in part by the Friends of the Utah Avalanche Center in Logan.

We've issued an Avalanche Watch for the Mountains around Logan including the Wellsville and Bear River Ranges and the Willard and Ben Lomond Peak Areas.

Bottom Line:

There's a CONSIDERABLE  avalanche danger and avalanches are possible on many slopes in the backcountry.  Triggered avalanches are probable on slopes steeper than about 35 degrees with significant deposits of heavy new snow.  Avalanche training and experience are essential for safe backcountry travel.    Continuing heavy snowfall, strong westerly winds, and mild temperatures may cause the danger to rise to HIGH in some areas later today, with both natural and triggered avalanches becoming likely on steep slopes in the backcountry.    

Mountain Weather:

The National Weather Service continued a Snow Advisory for the Northern Utah Mountains through noon today, and another 6 inches of heavy snow could accumulate today in the Bear River Range.  Westerly winds, averaging 30 mph with 50 mph gusts, along with mild temperatures and continuing heavy snow in the mountains are forecast for today.  A large and cold Pacific storm system will start to affect the region tomorrow.

Current Conditions:

Yesterday we found surface conditions Sierra-like, with deep heavy new snow stacked up on top of lighter powder from earlier in the week.  This is what we call inverted snow; heavy on top of light. Today if you get off the packed trail, it will be easy to get the sled stuck  in moist deep snow with a sugary structure-less base.  You might find conditions almost too deep and slow for turning, and you'll need to avoid most steep slopes because of dangerous avalanche conditions.  The Tony Grove Snotel site recorded 1.4 inches of accumulated water weight in the past 24 hours, with 2.1 inches in the last 48 hours.   The total snow stake only shows a 24 hour increase of around 5 inches of heavy snow.  Yesterday constant 30 mph west-southwest winds raked the high country with gusts in the 50 mph range.  With above freezing temperatures, the rain/snow line was up at around 7500'.  

Avalanche Conditions:

I'm thinking it will be a dangerous weekend in the mountains around Logan, so you may want to temper your plans, and at least stay off of and out from under steep slopes and avalanche paths.  Heavy snowfall, sustained westerly winds, and warming temperatures are building a cohesive slab on top of weak, sugary snow that we call faceted grains.  As the slab layer grows with continued accumulation today, the avalanche danger will continue to rise in the backcountry.  Triggered avalanches are possible on many steep slopes at mid and upper elevations in the region, and today some of these could be of considerable size, packing a dangerous punch.  Natural avalanches are possible on steep slopes in some locations.  The avalanche danger will be widespread on steep upper elevation slopes with recent slabby deposits of wind drifted snow.  Mid elevation shady slopes are plagued by extremely weak basal snow we call depth hoar, and avalanches are probable in these locations as heavy wet storm snow overloads the cohesion-less base.  Today, you should pay close attention to obvious signs of instability, like surface cracking and audible collapsing or whumfing noises. Choose safe routes, which keep you off of and out from under steep slopes, and remember to only expose one member of your party to potential avalanche danger at a time.

General Information:

I'll give a free Avalanche Awareness Talk, open to everyone, at the Logan Ranger District offices this evening at 6:30.

The Friends of the Utah Avalanche Center-Logan will present the 3rd annual fundraiser on Friday, January 19th at the Bullen Center in downtown Logan

 The Tony Grove Road is not maintained in the winter, and the heavy wet snow in the last couple days probably shut down wheeled access to the area near the lake.  You should be prepared to get stuck in a couple feet of snow if you try to head up.  Turning around may be difficult.  

   I'll update my advisories on Tuesday and Thursday evenings and weekend mornings by about 7:00.   I will update this advisory again later tonight, after my talk.  

Logan Area advisories will be accessible through the new statewide toll-free avalanche info line; 1-888-999-4019.

  Please  send backcountry observations to [email protected] or leave us a message at 755-3638, especially if you see or trigger an avalanche in the backcountry.

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.