Wasatch Cache National Forest

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

The Utah Avalanche Center Home page is: http://www.avalanche.org/~uac/

Avalanche advisory

Monday, April 14, 2003

Good Afternoon. This is Ethan Greene with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory for the Wasatch Range. Today is Monday, April 14, 2003, and it’s about 5:00 in the afternoon.

Current Conditions:

Snow surface conditions can only be described as variable. Today I found mostly damp snow with a thin surface crust below about 8,000’. Between 8,000’ and 9,000’ the surface crust is mostly breakable and becomes wet during the day. Above about 10,000’ the snow is mostly dry with both breakable and supportable surfaces. The good news is that the old dirt layer and the spring sunshine have combined to form a mosaic of wet and dry patches in mid-elevation areas. If you wax just right you can skidder across the frozen patches and then go head over heals in the wet sections.

Last night temperatures dipped into the mid 30’s at 8,000’ (low 40’s in the Ogden and Provo area mountains), and today under scattered clouds they climbed into the mid 40’s. Southwest winds have been blowing in the 20 mph range at most locations and gusting over 50 mph along the high ridges.

Avalanche Conditions:

Over the past few days the wet activity has been limited to fairly small point release avalanches on steep sun exposed slopes. Temperatures have been slowly cooling over the past 36 hours, and as a result the danger from wet avalanches is decreasing. The most interesting avalanche activity reported was a slide in Bunnels Fork in the Provo area mountains. A cornice fall triggered a point release avalanche that in turn triggered a slab avalanche. The slab portion was about 400’ wide and broke down into the weak snow near the ground. We suspect this avalanche occurred on Saturday and failed on dry faceted snow near the ground. Although the chances of triggering this type of avalanche will decrease over the next 24 hours, it is a good reminder that larger triggers can still produce deep slab avalanches.

By Tuesday morning we’ll have some new snow and moderate winds. The new snow should sit comfortably on the old rough surface, but fresh wind drifts will be sensitive to your weight. Use small slopes to gather information on the new snow stability, and approach deep wind drifts with caution.

Bottom Line (SLC, Park City, Ogden and Provo Area Mountains):

On Tuesday morning the avalanche danger will generally be LOW. As more snow accumulates during the day the avalanche danger will likely rise to MODERATE especially on steep slopes with fresh wind drift. If more than 12 inches of snow falls during the day the avalanche danger could reach CONSIDERABLE.

Western Uinta Mountains: Click Here

Logan – call 435-797-4146 or Click Here.

Mountain Weather:

A deep Pacific trough is moving into the Great Basin this evening bringing snow and cooler temperatures to the Wasatch. As the storm moves skies will become mostly cloudy and snow showers are likely. Snowfall rates will increase after midnight with snow expected to continue through Tuesday. Snow accumulations should be 2 to 4 inches by Tuesday morning with an additional 6 to 8 inches during the day. Areas favored by northwest flow could receive significant snowfall through tomorrow afternoon. The winds will be from the southwest in the 15 to 30 mph range overnight. On Tuesday wind speeds should drop into the 10 to 20 mph range and shift to the northwest in afternoon. A second broad trough moves into the Great Basin on Wednesday bringing a chance of snow during later half of the week.

General Information:

To report backcountry snow and avalanche conditions, especially if you observe or trigger an avalanche, 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.

Bruce Tremper will update this advisory some time Tuesday afternoon.

Thanks for calling!

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National Weather Service - Salt Lake City - Snow.

For an explanation of avalanche danger ratings:

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