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

Wednesday, December 07, 2005 7:30am
Good morning, this is Evelyn Lees with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory. Today is Wednesday, December 07, 2005, and it’s about 7:30 am.

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

Up coming avalanche awareness talks by the UAC staff include:
Dec 7 7 pm Lady of the Snows, Alta
Dec 7 7 pm Timpanogos Regional Hospital, Orem
Dec 13 7 pm REI, 3285 E, 3300 S, SLC
Dec 14 6:60 pm Mnt High Motorsports, 8262 S Redwood Rd, West Jordan
Dec 14 7 pm South Valley Unitarian, 6876 S Highland Dr.

Current Conditions:
Yesterday’s snow producing storm coated the mid and upper elevations with 1 to 2’ of classic Utah powder from the Logan to the Provo mountains. The snow water equivalent ranged from three quarters of an inch to an inch and an half. Temperature wise, it’s another toe numbing morning, with the mercury reading near zero at most locations. On the plus side, yesterday’s strong northwesterly winds have decreased to less than 15 mph.

Avalanche Conditions:
Yesterday, the combination of heavy snowfall and strong winds resulted in many reports of shallow new snow slides and sluffs, some running long distances. Highway control work in Little Cottonwood Canyon resulted in 3 slides reaching the road, and a party of snowmobilers triggered a slide with a debris pile deep enough to bury a machine. (We could use more information on this slide, so please give us a call at 524-5304. Thanks!) Today, it will still be possible to trigger new snow slides and sluffs, especially in wind drifted areas, with the larger slides having enough volume to catch, carry and bury a person. But I expect the new snow to stabilize rapidly today, and new snow slides to be harder to trigger by this afternoon.

The other avalanche problem is that the new snow may have once again overloaded the weak sugary facets near the ground on some slopes. This is the same tricky pattern as last week – there are only a few places where the weight of a person or new snow slide could trigger a slide on facets, but if released, the slide will be deep and dangerous. The most likely slopes to trigger a deeper slide would be northwest through easterly facing, above about 8,500’. So once again, give the facets some time to adjust to the new load. Start your backcountry travel today on lower angle, non wind drifted slopes, and very gradually work into the steeper terrain. Any collapsing is a sign of unstable snow.

Bottom Line:
The avalanche danger is CONSIDERABLE on slopes steeper than 35 degrees with recent drifts of wind blown snow. Both soft slabs and sluffs are possible, with drifting most common on northeast through southeasterly facing slopes. On a few shady slopes, facing the north half of the compass, it may be possible for slides to break on the weak facets near the ground, resulting in a deep, dangerous slide. Other steep slopes have a MODERATE danger.

Mountain Weather:
A very cold arctic air mass has settled across northern Utah and will remain in place through tonight. Partly cloudy skies this morning, with a few snow flurries possible. The northerly winds should remain less 15 mph. Frigid 10,000’ temperatures will stay near zero today. A dry air mass will be in place through the weekend, with 10,000’ temperatures gradually warming to near 20 Thursday.

Seasonal Weather History Charts. (NOTE: USE INTERNET EXPLORER FOR BEST VIEWING)

Please report any backcountry snow and avalanche conditions you observe. We appreciate all information. You can call (801) 524-5304 or 1-800-662-4140, or email to [email protected] or fax to 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.)

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

Bruce Tremper will update this advisory by 7:30 Thursday morning. Thanks for calling.