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.

 

AVALANCHE ADVISORY

Tuesday, December 20, 20057:30am
Good morning, this is Bruce Tremper with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory.Today is Tuesday, December 20, 2005, and itís about 7:30 am.

We are giving two free avalanche awareness talks this week:

Dec 21st†††††††† 7pm††† Wanship Fire Station

The beacon locator park at Snowbird is now open and free to the public.Itís sponsored by Wasatch Backcountry Rescue and Snowbird and located just off the bypass road in upper Little Cottonwood Canyon.

I will be giving a free avalanche awareness talk tonight at Wasatch Touring at 7:00 pm, which is at 1st south and 7th east in Salt Lake City.

Current Conditions: ††
Overnight, very dense snow continued to fall.Most of the range got around 2 inches but Little Cottonwood Canyon picked up 4 inches.However, it was a very non-Utah-like 15-20 % water weight with 0.6 Ė 0.8 inches of water.If we got that much water with last weekendís cold temperatures it would have produced 2-3 feet of snow.Thatís because temperatures are extremely warm this morning with the mountains in a misty, London-fog-like weather.Itís near freezing at 8,000í and 25 degrees on the ridge tops.Last night, winds blew 20, gusting to 40 on most of the ridge tops and 50 gusting to 70 in the most exposed peaks. Yesterday, backcountry travelers reported very difficult trail breaking conditions on the west side of the range where the new snow had quite a bit of rime in it and was upside down and slabby.On the east side of the range, through, the snow was not nearly as upside down and riding conditions were not too bad. So thatís probably the hot tip for the day.

Avalanche Conditions:
Yesterday, there was not a whole lot of avalanche activity in the backcountry as most people described the slabs as stubborn but explosive control work in the ski areas produced localized, stiff slabs.(Photo 1 from Provo, Photo 2 from Provo) The avalanches tended to break up above you and once they got going, they produced a high volume of snow that ran a long way. Today, Iím worried about two different avalanche problems:

First, the winds blew hard last night from the west, so you will likely find some hard wind slabs along the ridge tops. These will likely be hard to trigger but they will break above you and could be large.So as always, you should avoid any steep slope with recent wind deposits.

The second avalanche problem is the very weak layers of buried faceted snow that formed during the dry spell these past couple weeks.Weíve had quite a bit of water weight added over the past three daysóbetween 1.5 to 2.5 inches and Iím a bit worried about all the new weight overloading those layers, especially in the thin snowpack areas.†† So today, you should continue to be very suspicious of steep slopes that face the north half of the compass as well as east facing slopes, especially in thinner snowpack areas.

Bottom Line:
Although most slopes have a MODERATE danger today, there is a CONSIDERABLE danger on any steep slope with recent wind drifts, which you will find mostly along the ridge tops.There is also a CONSIDERABLE danger on any steep slope that faces north through east quadrants of the compass, especially in thin snowpack areas such as at mid slope.Avalanches on these slopes will likely be difficult to trigger but if you do they will likely be medium to large and difficult to escape.

Mountain Weather:
Today will be very warm and moist with fog and scattered clouds.Ridge top temperatures will be around freezing and 8,000í temperatures will be in the upper 30ís.Ridge top winds have died down and should stay reasonable at around 10-15 mph from the west.We have a weak ridge building over us to today with even warmer temperatures on Wednesday.Then, we should get another shot of snow for northern Utah on Thursday and Friday.After that, we have a ridge building over us for the holiday weekend.

Regional Snow Profile (this profile can also be found daily off our home page under avalanche products)

Seasonal Weather History Charts.

Yesterday, Wasatch Powderbird Guides didnít get out due to weather and they probably wonít get out today either.If they can get out today, theyíll be in Cardiff, Days, Mineral, Grizzly, with another ship in American Fork.For more info, call 742-2800.

We appreciate any backcountry snow and avalanche conditions you observe.Call (801) 524-5304 or 1-800-662-4140, email [email protected] or 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.

To have this advisory automatically e-mailed to you each day, click HERE.(You must re-sign up this season even if you were on the list last season.)

UDOT also has a highway avalanche control work hotline for Little Cottonwood road, which is updated as needed. 801-975-4838.

The annual report for 2004-05 is now on the web. (Click HERE, 8mb)

I will update this advisory by 7:30 Wednesday morning.Thanks for calling.