Wasatch Cache National Forest

In partnership with: The Friends of the Utah Avalanche Forecast Center, Utah Department of Public Safety Division of Comprehensive Emergency Management, Salt Lake County, and Utah State Parks

: http://www.avalanche.org/~uac/

Avalanche advisory

TUESday. November 11, 2003 7:30 am

Good morning, this is Evelyn Lees with the Forest Service Utah Avalanche Center with your avalanche and mountain weather advisory. Today is Tuesday, November 11, 2003, and it’s 7:30 a.m.

Current Conditions:

Skies are partly cloudy this morning, and temperatures are in the upper teens to near 20. The winds are 10 to 15 mph from the west, and starting to increase. Storm totals from Sunday night were 5 to 10” of dense snow, with the higher elevations and the Ogden and Provo mountains receiving the most snow. The dense snow helped to fill in old tracks, and turning conditions are very good, especially on shady upper elevation slopes that received a bit more snow. But with the total snowpack averaging only about 2’, most backcountry travelers are still hitting the occasional rock.

Avalanche Conditions:

Over the past 5 days, the snow pack has developed as much variety as the candy in a Halloween bag. There was so much diversity in yesterday’s field observations, we might as well been skiing on different planets.

Provo mountains had the most avalanche activity – 2 more natural slab avalanches were reported, the largest 250’ across, initiating at 8000’. A few drainages in upper Little and Big Cottonwood also had very sensitive avalanche conditions, above about 10,000’. Ski cuts were releasing new snow avalanches, 8 to 14” deep, which were entraining a lot of snow as they ran. These were on northerly through easterly facing slopes and running on a layer of buried surface hoar crystals. Some of these slides were breaking lower off the ridgelines and on slopes of only about 35 degrees. This sensitive, buried surface hoar layer may be very localized to a few drainages and/or the higher elevations.

Else where through out the central Wasatch, reports from the backcountry were of stable snow, with many steep shots being skied with no incident. Most of these reports of stable snow were from elevations below about 9,600’.

To further complicate the picture, strong westerly winds are in today’s forecast. The speeds should get high enough to start blowing and drifting the dense new snow, and I expect stiff sensitive wind drifts to start forming along ridges and exposed areas.

Bottom Line (Salt Lake, Park City and Ogden area mountains):

Below about 9,500’, the avalanche danger is MODERATE on any slope steeper than about 35 degrees with fresh deposits of wind blown snow. Other slopes have a generally LOW danger. Above about 9,500’, the avalanche danger is CONSIDERABLE on slopes steeper than about 35 degrees, especially with fresh deposits of wind blown snow.

PROVO area mountains: The avalanche danger in the Provo mountains is CONSIDERABLE on slopes steeper than about 35 degrees, and MODERATE on slopes steeper than about 30 degrees. In these areas, human triggered avalanches are probable and natural avalanches possible. The danger in the Provo area mountains increases with elevation, and will increase during the day as the winds increase. Avoid any slopes with new drifts of wind blown snow.

Mountain Weather:

Today, the northern mountains will have mostly cloudy skies, with a few light snow showers. The westerly winds will increase into the strong range, with 30 to 35 mph averages. Highs today will be near 30 at 8,000’ and near 20 at 10,000’. Tonight, skies will be mostly cloudy early, then clearing by morning. Winds will shift to the northwest and decrease. Wednesday should be cool and clear. A couple of weak disturbances are forecast to move across northern Utah later this week – one Wednesday night into Thursday and another over the weekend.

General Information:

If you are getting into the backcountry, please give us a call and let us know what you’re seeing, especially if you trigger an avalanche. You can leave a message at 524-5304 or 1-800-662-4140. Or you can e-mail an observation to uac@avalanche .org, or you can fax an observation 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.

Andrew McLean will update this advisory Wednesday morning.

Thanks for calling!

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For more detailed weather information go to our Mountain Weather Advisory

National Weather Service - Salt Lake City - Snow.

For an explanation of avalanche danger ratings:

http://www.avalanche.org/usdanger.htm