Tuesday, January 11, 2000, 7:30 am Good morning. This is Seth Shaw with the Forest Service Utah Avalanche Forecast Center with your backcountry avalanche and mountain weather advisory. Today is Tuesday, January 11, and its 7:30 in the morning. This forecast is sponsored by a generous donation to the Friends of the Utah Avalanche Forecast Center by Kirkhams, where you can always rent before you buy. Check out their wide selection of ski, snowshoe, and safety equipment at 3125 S State in SLC. Current Conditions: Last night the mountain picked up a few more inches of dense snow and the winds continued to blow hard out of the WSW, around 30 to 40 mph. In the past 24 hours most mountain locations received 6 to 12 inches of 12 % to 18 % density snow, in many places the first half of that snow was graupel with denser snow falling on top of it. In the past 10 days the Alta guard station has received over 5 inches of water equivalent. Id say we are getting close to a major avalanche cycle. Avalanche Conditions: Ill start with some of the avalanches I know about. Starting in south, there were several slides to the ground on the NW face of Spanish Fork Peak in the Provo mountains. The largest of these was reported to be 400 feet wide. The starting zone was near the ridge at around 10,000. Near Sundance at a lowly 6,300 on a north aspect, a 200 wide slab spontaneously broke out on wet facets on the ground, it sympathetically pulled out another slide 150 away. In the Ogden Mountains at a closed ski resort a snowcat triggered a slide 3 to 5 feet deep to the ground on a ENE aspect, the slope angle was a measly 33 degrees. There were numerous human triggered and natural avalanches in the Salt Lake and Park City area mountains yesterday. These have been mostly new wind slabs from one to three feet deep. The weak layers out there read like a chapter out of an avalanche text. You got your wind slabs, graupel layers, density inversions, buried surface facets, rain and rime crusts, and last but certainly not least, depth hoar trying to support this whole wobbly mess. Oh yeah, and rapid warming could be a player today, especially at lower elevations. Dont be the straw that breaks the poor beasts back. As always, recent avalanches or cracking and collapsing of the snowpack are sure signs of instability. The only way to be certain to avoid the avalanche dragon in the backcountry today is to stay on slopes 30 degrees or less steep. Wind sheltered slopes will be much safer than wind deposited slopes. Wind scoured slopes will be the safest. Also be aware of the slope angle above you and on adjacent slopes. It will be possible to trigger a steeper slope from low angle terrain and if it goes to the ground it could pull the low angle slope with it. In general west facing slopes will be wind scoured and east facing slopes will be wind deposited but you will need to judge each slope individually. Now that Ive painted a grim picture, I should retract a little bit. I think most of the human triggered activity in the Salt Lake area mountains today will be newly formed wind slabs or on the graupel layer that fell yesterday and will require a slope of 35 degrees or steeper to get it to move. Personally though, I would stay off the steep stuff for fear of the deep slab, especially outside of Big and Little Cottonwood Canyons where the underlying snowpack is weaker. Bottom Line: Today there is a High danger of human triggered avalanches on wind loaded slopes 35 degrees and steeper, that means both human triggered and natural avalanches are likely. There is a moderate hazard on steep wind sheltered slopes, meaning that human triggered slides will be possible. Be on the lookout for cross loading around sub ridges and gullies and in unusual places including loading down off the ridges. Weather: Continued strong WSW winds with light snowfall, gusts will be in the 50s on higher ridges. The mountains should pick up a few inches of snow today, mostly this afternoon. Tonight it should snow another 5-10 inches. Today the 8,000 foot high temperature should be around 38 degrees and near 30 degrees at 10,000 feet. A few showers will linger into Wednesday. Thursday and Friday we will get a break with another storm on the weekend. I will do an afternoon update on our longer forecast advisory by 1pm this afternoon. You can access this number by dialing 801-364-1591 Snowmobile: The Utah State Parks Department has funded two part time snowmobile avalanche educators. They are available to provide free avalanche education for snowmobile groups. For more information call the Utah Avalanche Forecast Center at either (801) 524-5304 or 800-662-4140. There is still space available in the Friends of the Utah Avalanche Forecast Centers January 15 17, 3 day avalanche class. For more information, contact customer service at REI at 801-486-2100. You can get this advisory and other avalanche and mountain weather info on the net at: [25]www.csac.org. Click on Salt Lake City to get specific information for our area. To report snow and avalanche conditions, especially any avalanche activity call 801-524-5304 or 1-800-662-4140. The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content. The advisory describes general avalanche conditions and local variations always occur. Ethan Greene will update this advisory by 7:30 Wednesday morning.