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


Friday, December 21, 2007  7:30 am
Good morning, this is Brett Kobernik with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory.  Today is Friday, December 21, 2007 and it’s about 7:30 am.


I’ve continued the avalanche warning through 6pm tonight.  Strong winds over the last 24 hours coupled with more new snow has elevated the avalanche danger to HIGH on many upper elevation steep slopes.  People without expert level snow and avalanche assessment skills should avoid the backcountry today.


Little Cottonwood Canyon will be closed this morning while avalanche control work is performed.


Current Conditions:

It’s officially a mess.  A welcome mess but nonetheless a mess.  Take a good amount of upside down snow, add strong winds with another good shot of snow overnight and I think most people can do the math.  The floatation index yesterday morning was very low with most people experiencing difficult trail breaking and difficult riding conditions making them drool for larger tools to navigate through the snow.  Winds gradually picked up during the morning and really started drifting snow afternoon adding to the upside down feel to the snow.  Since the passing of the front yesterday at around 5pm the Cottonwoods and Park City Ridgeline picked up another 12 to 18” inches of lighter density snow.  The Ogden area didn’t get as much but still received around 6 inches and the Provo area received around 9 inches or a bit more.  Clearing is currently happening in Provo right now but snow showers continue in the Cottonwoods and Ogden area.  Even with the good amount of new snow there is still a relatively thin snowpack especially in the lower elevations.  Be careful of lurking surprises and keep in mind “lumps could be stumps”.


Avalanche Discussion:

Natural avalanches were reported from a number of locations in Little Cottonwood Canyon on Thursday.  There were human triggered avalanches as well with at least one person getting caught, carried and partially buried on the south facing slope about two thirds of the way up Flagstaff in Little Cottonwood.  There were also a number of unintentionally triggered pockets in other areas of the southerly facing slopes above the town of Alta as well as a slide in the West Bowl of Silver Fork which was around 150 feet wide, 12 inches deep and ran around 500 feet vertical.  A skier traversing a ridge near Claytons Peak near Brighton remotely triggered a slide that broke 12” deep, 60 feet wide which ran the entire length of the east facing bowl.


It’s not worth splitting hairs on the various weaknesses within the snow right now.  Winds played a significant roll in drifting the snow into sensitive slabs on many aspects Thursday afternoon.  Some upper elevation north aspects may have avalanched breaking into old snow.  We probably went through a natural avalanche cycle overnight which will be subsiding this morning.  However, many slopes will be sensitive to the weight of a person still today.  A number of savvy backcountry skiers I talked to are not venturing into the backcountry today and will let the new snow settle somewhat before poking around.


Bottom Line for the Ogden, Salt Lake, Park City and Provo area mountians:

The avalanche danger remains HIGH on slopes approaching 35 degrees especially at the upper elevations that were exposed to the winds.  The danger is CONSIDERABLE on slopes without recent wind deposits but you will have to look carefully to figure this out as many drifts are now covered up.


Mountain Weather: 

We should see a few more inches of snow this morning before things taper off.  Temperatures will be in the teens today with northwest winds picking up slightly this morning then tapering off as the day progresses.  Saturday will bring partly cloudy skies which will probably coax a large amount of people into the backcountry.  It’ll be hard to keep from getting a case of powder fever but I’d urge people to use caution through this busy weekend.


The Wasatch Powderbird Guides will do recon later today if they get the chance.  They will operate outside of the Tri Canyon area this Saturday.  They will use a Monday exchange in the future.


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.

Evelyn Lees
will update this advisory by 7:30 Saturday morning.