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:

 

To have this advisory automatically e-mailed to you each day free of charge, visit: http://www.mailermailer.com/x?oid=16351h          

For photos of avalanches and avalanche phenomenon, visit:  http://www.avalanche.org/%7Euac/photos_03-04.htm      (Updated 3/25)

Photos sent in by observers throughout the season visit:  http://www.avalanche.org/~uac/obphotos/observer.html      (Updated 4/2)

For a list of backcountry avalanche activity, visit:  http://www.avalanche.org/%7Euac/Avalanche_List.htm     (Updated 3/31)

 

Early morning preliminary information by about 6:00 am: 801-364-1591

 

Avalanche Advisory afternoon update

Sunday, April 18, 2004  5:30pm

 

Good afternoon, this is Drew Hardesty with the Forest Service Utah Avalanche Center with an afternoon update.  Today is Sunday, April 18 and it’s 5:30pm.  This information is time sensitive and will expire by Monday evening.  Click here to see our standard end of the year bulletin which has links to weather sites and information as well as some general tips and guidelines for the spring avalanche season. 

 

Current Conditions:

Well, it’s about time.  It felt good to break trail again and at least pretend that we were back in winter.  Storm totals across range as of 5pm are 2-3” in the Logan mtns, 6-7” in the Ogden, Park City,  and Uinta mountains, 3-6” in the Provo mountains, and 12-17” in Big and Little Cottonwood.  Densities averaged 8-10%, providing a good base above the old crusts.  Winds in the Ogden mountains averaged 20-30mph from the west, but elsewhere, ridgetop wind speeds were less than 15mph.  Because the snow came in two waves, the intermittent sun dampened the sun exposed slopes, but northerly facing slopes will still hold excellent powder.  Don’t forget that many of our southern exposures had little, if any snow before the new snowfall.

 

Avalanche Conditions:

Today’s avalanches were a mixed bag of cold dry sluffs, sun activated wet point releases, and some localized 8-10” soft slabs, some up to 150’ wide in upper Little Cottonwood.   The avalanches were primarily running within the new snow, and then entraining all the snow down to the crust once it had gained enough momentum.  The dry and wet-activated sluffs were big enough to pack a punch with some producing decent debris piles down in the flats below.   Unless you were careless, these were easy to trigger on a ski cut and easy to avoid on a diagonal fall line.  Regarding the soft slabs, my hunch is that the highest sensitivity peaked in the mid-morning, corresponding to the high precipitation rates, but suspect that the moderate temps have settled most of them out by now.  Clearly, the lack of wind kept the activity to a minimum.   The other concern for Monday will be losing an edge on the slick crust or by being knocked over by a sluff and then rag-dolling down the slope, over cliffs, through trees, and into the creek. 

BOTTOM LINE FOR THE SALT LAKE, PARK CITY, OGDEN, AND PROVO MOUNTAINS:  On slopes less steep than 35 degrees, the danger is LOW.  On slopes steeper than 35 degrees, the danger is MODERATE for loose snow avalanches.   If the sun comes out on Monday, the danger of wet point releases will spike on all steep sun-exposed slopes, and human triggered avalanches will be probable.  There may still be a few isolated pockets of soft slab that are sensitive to the weight of a person on steep upper elevation slopes and if the winds pick up, the danger will rise accordingly.  Due to stronger winds in Ogden, the danger of human triggered avalanches is MODERATE.

Mountain Weather:  We’ll get a bit of a break Sunday night with another disturbance expected to move into northern Utah Monday afternoon that should produce a few more inches of snow.  Winds Sunday night should be light out of the southwest, increasing to 20mph by Monday mid-morning.  8000’ temps will be in the mid 20’s tonight, and the mid-thirties on Monday.  10,000’ temps tonight will be 25 degrees tonight and Monday.  Another stronger storm should arrive by Wednesday afternoon that looks to bring snow to the valleys and heavy snow to the mountains. 

Backcountry snow and avalanche information is still useful to us.  So if you’re still getting out and see anything of interest, leave us a message at 524-5304, 1 800-662-4140, drop us an email at [email protected], or a fax to 524-6301.  The information in this advisory is from the US Forest Service, which is solely responsible for its content.  This advisory describes general avalanche conditions and local variations always occur.

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