This is Matt Lutz of the Sawtooth National Forest Avalanche Center
 with your Backcountry Avalanche Advisory and Weather Forecast for
 Thursday, December 27, 2007 at 7:30 am.

 The Sun Valley Telemark Series & Smiley Creek Lodge & the Friends of
 the Sawtooth Avalanche Center bring you this advisory.

 Bottom Line:
 Today the overall avalanche danger is estimated to be MODERATE.

 Keep in mind that with a MODERATE danger rating there is still a
 possibility of human triggered avalanches. Human triggered avalanches
 today could occur on recently wind loaded slopes, in high alpine
 terrain, and on slopes over 38 to 40 degrees.

 The snowpack is currently not very trustworthy in my opinion. This is
 due to a highly variable early season snowpack, the presence of
 persistent weak layers and recent widespread wind activity. Slope by
 slope evaluation should take place as you move through the
 backcountry.

 Primary Avalanche Concern:
 
 
 
 
 The South and Central Valley still have a rather thin snowpack which
 is generally very weak throughout. Steep wind loaded terrain in the
 South and Central Valley could still produce an avalanche with the
 right trigger.

 The North Valley, Salmon Headwaters and Sawtooth Mountains have a
 generally deeper and stronger snowpack, but persistent faceted grains
 can still be found in many locations. Solar aspects, ridgelines and
 exposed high elevation terrain in these areas likely have large grain
 facets near the bottom of the snowpack.

 The near surface facets that developed in mid December are likely
 slowly gaining strength, but are still present in many locations. This
 layer is now between 16 inches to 3 feet deep. I suspect that the near
 surface facets are still a factor in areas from the central Sawtooth
 Mountains to the south where the overall snowpack is less than 4 to 5
 feet deep. Poor stability tests and clean shears on this layer should
 indicate whether or not it will be a problem where you are. Reports
 from the northern Sawtooth Mountains indicate that the mid December
 near surface facets are no longer reactive with stability tests.

 Secondary Avalanche Concern:
 
 
 
 
 Over the last week we have seen a few wind events blow through our
 forecast area. Christmas Eve saw a wind event that seemed to affect
 almost all exposed slopes regardless of elevation. Be aware of
 recently deposited wind slabs, especially in areas with an overall
 thin weak snowpack and along steep exposed ridgelines. Many of these
 wind affected areas will be visually obvious at least until they get
 buried with a few inches of new snow. Other clues to their presence
 are texture changes, supportable hollow sounding slabs, cracking,
 whumpfing and recent natural releases in similar terrain.

 Additional Discussion
 Unfortunately on both Christmas Eve and Christmas day there were
 avalanche fatalities in Utah. One was an inbounds skier and the second
 was a snowmobiler. Initial reports from both accidents indicate that
 the weak layer was probably large grain faceted snow buried deep
 within the snowpack. This is important for us to understand and
 remember since much of our forecast area also has a layer of deep
 large grained faceted snow. Our most sincere condolences go out to the
 victims, their families and all the avalanche workers involved with
 these events.

 Current Conditions:
 Our forecast area currently offers a mixed bag of riding conditions.

 These conditions range from nice soft snow in sheltered locations, to
 punchy weak snow at lower elevations and semi punchy wind affected
 surface snow on exposed slopes. Ketchum is under clear skies.

 Temperatures in the valleys are in the negative single digits. Ridge
 top temperatures are hovering around 0 degrees, but with the light
 northwesterly winds factored in, the temperatures will feel like -10
 to -20 degrees.

 Mountain Weather Forecast:
 Today expect clear to partly cloudy skies during the day with
 continued cold temperatures. Tonight light snow is expected to develop
 over the Central Mountains of Idaho and last through Friday. On
 Saturday the National Weather Service is calling for a sizeable storm
 accompanied by a lot of wind.