Wasatch Cache National Forest
In partnership with: Utah Division of State Parks and Recreation, The Friends of the Utah Avalanche Center, Utah Department of Emergency Services and Homeland Security and Salt Lake County.

“keeping you on top”


Saturday, December 08, 2007  7:30 am
Good morning, this is Evelyn Lees with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory.  Today is Saturday, December 08, 2007 and it’s about 7:30 am.


Avalanche Watch:

A special avalanche advisory has been continued for the mountains of Northern Utah including the Western Uinta mountains and the Ogden, Park City, Salt Lake, Provo and Logan area mountains.  The avalanche danger will remain HIGH on the upper elevation northerly facing slopes in the Salt Lake and Provo area mountains throughout the weekend.  Heavy snowfall has over loaded a preexisting weak snowpack and both natural and human triggered avalanches are likely.  Backcountry travel is not recommended on upper elevation, northerly facing terrain in the Provo and Salt Lake area mountains.  Other mid and high elevation mountainous terrain has a CONSIDERABLE avalanche danger, and backcountry travelers should avoid steep slopes and avalanche runout zones.  People without excellent route finding and snow stability skills are urged to use caution if going into the backcountry.


Current Conditions:

We needed winter and it’s finally arrived.  Storm totals as of 6 am include 16 to 28” in the Ogden area mountains, 14 to 19” on the Park City side, 20” to 30” in the Cottonwoods, and 14 to 24” in the Provo area mountains.  Temperatures are in the upper teens to mid 20’s.  The southwesterly winds have mostly been well behaved – in the 10 to 15 mph range, except for a few hours overnight where they blew in the 20 to 30 mph range, with gusts to 40 along the highest ridges.  With deep, deep powder, trail breaking might require a team effort today.  Coverage is much improved at the lower and mid elevations, and access via most roads and trails will be good.


Avalanche Discussion:

Yesterday, reports of avalanche activity into old snow were concentrated in the upper elevations of the Cottonwoods - upper Days, Silver and Big Cottonwood.  Slides were about 50-75' wide, with one triggered remotely, and several large collapses reported, all on northerly facing slopes, above about 9,500’.  New snow soft slabs were much more widespread on steep slopes, with slides failing at both the density change within the new snow and near or at the new snow/old snow interface.


Today, the HIGH avalanche danger will be on any slope that has old, weak facets near the ground.  This weak layer is most widespread on the upper elevation, northerly facing slopes in the Cottonwoods and Provo area mountains, with smaller pockets occurring along the Park City ridgeline.  Here, on steep slopes, both human triggered and natural avalanches 2 to 3 feet deep are likely.  Slides can be triggered remotely, from above, the side and below.  TRAVEL IS NOT RECOMMENDED ON AND BELOW THESE STEEP, NORTHERLY FACING SLOPES.


On other steep slopes through out the range, it will be possible to trigger new, soft snow slab avalanches.  These will be the most sensitive and wide spread along the highest ridges and peaks where the winds blew more strongly for a few hours last night.  Natural avalanches are possible in the steepest terrain, especially if you’re in an area where when precipitation intensities increase or if the winds start to blow and drift snow.  There are numerous safer places to recreate today – on slopes less steep than about 35 degrees and below about 9,500’ in elevation, and especially if you avoid the northerly facing slopes that retained old, October snow.


Bottom Line:

Salt Lake, Park City and Provo area mountains: The avalanche danger is HIGH on northwest, north and northeast facing slopes above about 9000 feet, where avalanches  up to 3’ deep could be triggered, failing on a weak faceted layer.  The avalanche danger is CONSIDERABLE on other mid and upper elevation slopes steeper then around 35 degrees, with human triggered avalanches of new snow up to 2’ deep probable and natural avalanches possible.


Ogden area mountains: The avalanche danger is CONSIDERABLE on mid and upper elevation slopes steeper than about 35 degrees, with human triggered avalanches of new snow probable and natural avalanches possible.   


Mountain Weather: 

An upper level trough will remain over northern Utah throughout the weekend.  Light to moderate snowfall expected today, with 6 to 9” of additional snow possible.  Temperatures will be in the low 20’s at 8,000’ and the mid teens at 10,000’.  The winds will be light and variable, in the 5 to 15 mph range at most locations.  Only across the highest peaks and ridges will southwesterly winds reach speeds of 20 mph with gusts to 25.  Snowfall intensity will increase again late this afternoon through tonight, with an additional 8 to 12” possible by Sunday morning.



Wasatch Touring in Salt Lake City will have a beacon park set up at their shop today Saturday and you can demo several brands of beacons.

For an avalanche education
class list, click HERE.  

If you want to get this avalanche advisory e-mailed to you daily click

The UAC has temporary job openings for doing avalanche outreach in more rural areas.
  Click HERE for info.

UDOT highway avalanche control work info can be found HERE or by calling (801) 975-4838.

Our statewide tollfree line is 1-888-999-4019 (early morning, option 8).

For our classic text advisory click HERE.

If you’re getting out and see anything we should know about please let us know.  You can leave a message at
(801) 524-5304 or 1-800-662-4140, or email us at [email protected]. (Fax 801-524-6301)

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.

Drew Hardesty
will update this advisory by 7:30 Sunday morning.