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.

                        The Utah Avalanche Center Home page is: http://www.avalanche.org/~uac/

                                          (click on) Utah Avalanche Center in Logan for our home page           

Logan area Avalanche advisory

 December 12, 2006

Hello, this is Toby Weed of the Utah Avalanche Center in Logan with your backcountry avalanche and mountain weather advisory.  It's Tuesday December 12th, and it's 9:00 in the evening.  This advisory is brought to you in part by the Friends of the Utah Avalanche Center in Logan with help from Backcountry Access.

Mountain Weather:

 The National Weather Service continued a Snow Advisory for the Northern Utah Mountains through 4:00 Wednesday afternoon.  And under a moist westerly flow, a conveyer-belt of Pacific moisture-filled clouds continue to bring it on in, like a giant fire-hose trained directly on the Logan Area Mountains.  Tonight and tomorrow promise continued snowfall at upper elevations along with steady west winds and warming temperatures. The rain/snow line will move up to around 7000' in elevation on Wednesday afternoon, but a moist foot-and-a-half of additional accumulation is possible on upper elevation slopes by Thursday morning.   A cold and potent Pacific storm is forecast to move into the region over the weekend.

Avalanche Conditions:

Heavy snowfall, sustained westerly winds, and warming temperatures are all helping to build a cohesive slab on top of weak, sugary snow that we call faceted grains.  As the slab layer grows with continued accumulation in the next couple days, the avalanche danger is likely to rise dramatically in the backcountry.  Tomorrow, triggered avalanches will be possible on many steep slopes at upper elevations in the region, and by afternoon some of these could be of considerable size, packing a dangerous punch.  Natural avalanches may become possible on steep slopes in some locations.  The danger will be highest on steep slopes with recent deposits of wind drifted snow.

 I'm most concerned about avalanches occurring on north through southeast facing slopes steeper than about 35 degrees and above about 8000' in elevation.  But triggered avalanches may become possible on other slopes as well. Mid elevation shady slopes are plagued by extremely weak basal snow we call depth hoar, and avalanches will become possible in these locations with significant accumulations. On Wednesday and Thursday 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.

 Bottom Line:

There's a MODERATE avalanche danger and triggered avalanches are possible on many slopes in the backcountry. Avalanches are most likely on north through southeast facing slopes steeper than 35 degrees and above about 8000' in elevation.   Heavy snowfall, sustained winds, and warming temperatures will cause the danger to rise to CONSIDERABLE on steep slopes with significant deposits of new snow by Wednesday afternoon. This means that triggered avalanches will be probable and naturals possible.

General Information:

I'll give a free Avalanche Awareness Talk, open to everyone, at the Logan Ranger District offices on Thursday, December 14th at 6:30.

 The Tony Grove Road is not maintained in the winter.  That means, you can't quite drive a wheeled vehicle all the way to the lake, and you should be prepared to get stuck in a couple feet of snow if you try.  Turning around may be difficult.   With limited access to upper elevation snow elsewhere, there's lots of snow-hungry people on the Tony Grove Road.   Motorized users need to be aware of this, and we need to keep our speed way down in the proximity of pedestrians.   

   I'll update my advisories on Tuesday and Thursday evenings and weekend mornings by about 7:00.  This advisory will expire on Wednesday night, and I will update it again on Thursday night.  Logan Area advisories will be accessible through the new statewide toll-free avalanche info line; 1-888-999-4019.

If you're confused by some of our avalanche terms check out the cool new Avalanche Encyclopedia.  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.