This is Matt Lutz of the Sawtooth National Forest Avalanche Center
 with your Backcountry Avalanche Advisory and Weather Forecast for
 Sunday, January 6, 2008 at 7:30 am.

 The Twin Falls District Bureau of Land Management & the Friends of the
 Sawtooth Avalanche Center bring you this advisory.

 Special Announcement:
 We have issued a BACKCOUNTRY AVALANCHE WARNING with the National
 Weather Service for the mountains of South Central Idaho.

 (This does not apply to operating ski areas and highway
 programs-Respect all closures these operations have.)
 Bottom Line:
 Today the avalanche danger is estimated to be HIGH. Recent heavy
 snows and strong winds have produced large areas of unstable snow.

 Human triggered and natural avalanches are likely on steep
 snow-covered slopes and gullies.

 Travel in avalanche terrain or avalanche run-out areas is not
 recommended. These types of areas include not only large backcountry
 slopes, but also small steep slopes and run-out zones commonly found
 within the urban interface.

 Primary Avalanche Concern:
 
 
 
 
 Over the last 48 hours our forecast area has received between one to
 two and a half feet of new snow. This new snow has been accompanied by
 moderate to strong southerly winds. The overall new snow distribution
 varies widely due to the wind component of the storm. Additionally the
 new snow fell onto a relatively weak old snow surface. This is a great
 recipe for an active avalanche cycle.

 Through out our forecast area there were numerous natural and human
 triggered avalanches reported and observed yesterday. The South and
 Central Valley saw a very wide spread shallow slab avalanche cycle.

 These slabs were failing on a variety of layers including the old snow
 surface, large grained facets deeper within the snow pack and on a
 graupel layer deposited within the new snow. Any slope that was not
 wind swept clean during the storm currently has the potential to
 avalanche.

 We also received reports of natural avalanches in the North Valley and
 Sawtooth Mountains. The failure layer for these slides was reported to
 have been a graupel layer within the new snow. The potential for
 larger more destructive slides exists in our northern terrain due to
 larger new snow fall amounts and buried facets deep within the old
 snow.

 Secondary Avalanche Concern:
 
 
 
 
 The old snow within the South and Central Valley was very thin and
 weak. Any slope over 30 degrees that did not already avalanche still
 has the potential to do so. Areas to pay special attention to are
 steep slopes, wind loaded exposed slopes and ridgelines. Most of the
 wind loading appeared to take place on east, northeast and north
 facing slopes.

 The North Valley and Sawtooth Mountains generally had a deeper and
 stronger snowpack prior to this last storm. I suspect that there was
 an active avalanche cycle over the last 36 hours within the storm
 snow. The possibility of a deep slab avalanches involving old snow
 exists due to the buried large grain facet layers within the old snow.

 If a human trigger initiates a slide that involves old deep snow it
 will likely be large, destructive and not survivable. This type of
 avalanche is most likely to occur in areas that are steep, rocky, high
 alpine, or areas that prior to this last storm had thin and variable
 snow cover.

 If I have not painted a clear enough picture folks, today is a good
 day to be very careful and stay off steep slopes and stay out of run
 out zones. Watching Sunday football games is a good alternative.