This is Janet Kellam of the Sawtooth National Forest Avalanche Center
 with your Backcountry Avalanche Advisory and Weather Forecast for
 Saturday, December 29, 2007 at 7:30 am.

 The Sawtooth Society in partnership with Idaho's SNRA Mountain Goat
 license plate program & the Friends of the Sawtooth Avalanche Center
 bring you this advisory.

 Bottom Line:
 Today the avalanche danger is estimated to be MODERATE in most
 locations with the danger increasing as the current winter storm
 progresses. Continue to watch for areas of weak underlying snowpack
 where slides may be triggered, especially in steep rocky terrain.

 The bulk of the storm will not arrive until tonight and tomorrow, but
 watch for changing conditions and warning signs of avalanche
 conditions such as cracking and collapsing of the snowpack and small
 avalanches on steep cutbanks. Stay heads up and have several options
 of more moderate terrain as the storm progresses and conditions
 change.

 Due to our winds increasing throughout the day and moderate amounts of
 new snow the avalanche danger will increase to CONSIDERABLE on
 steep slopes along or beneath exposed ridgelines. Shallow, new wind
 slabs will become a problem today with larger areas and deeper
 snowpack expected to be unstable once the newer snow accumulates.

 The northern sectors have already gotten more snowfall than around
 Ketchum and Baldy and we will see conditions begin to change there
 first.

 Primary Avalanche Concern:
 
 
 
 
 Yesterday afternoon in the Galena Summit area, shallow slabs of newer
 snow and windblown snow began to form. Too small to be a problem
 yesterday, these slabs will become larger and more sensitive as new
 snow and wind drifted snow accumulate and temperatures warm up.

 Closer to Ketchum, we received almost no snow yesterday so this area
 will not develop wind slabs as quickly as locations with more new
 snow.

 Secondary Avalanche Concern:
 
 
 
 
 In the Central and South Valley:
 Weak snow is prevalent at all elevations. Once new snow and windblown
 snow accumulate we expect to see avalanches occur on steep slopes,
 especially with human triggers. These slides may become fairly large
 due to the widespread layer of faceted snow near the ground. It is
 uncertain just how much new snow will induce avalanche activity. I
 dont think today will produce enough but it doesnt hurt to be heads up
 about it as the consequences can be serious. Human triggered slides
 will tend to occur before naturals.

 In the North Valley and locations with a deeper snowpack: 
 This weak snow is not as widespread. However, pockets of weak snow are
 scattered throughout any steep, rocky terrain in our region. It is
 difficult to pinpoint just where the weaker areas are so this somewhat
 unpredictable pattern requires careful evaluation and more
 conservative route selection as the storm progresses.

 Current Conditions:
 Yesterday winds remained light from a westerly direction but have
 increased in speed, blowing in the teens and gusting 20 to 30mph.

 Although slightly warmer than yesterday, temperatures are still cool
 at high elevation, 7 degrees on Titus and Baldy.

 Snowfall began about 4AM this morning and accumulations are light in
 most places, 4 or 5 inches of snow appear to have fallen in the
 Headwaters of the Salmon and northern Sawtooth Mountains since
 yesterday.

 Surface conditions are settled powder with todays new snow on top in
 sheltered locations. Variable wind crusts exist on any slopes exposed
 to north and west winds. Warmer aspects are more consolidated but are
 yet to develop a sun crust.

 Mountain Weather Forecast:
 A winter storm warning will be in effect beginning late today. Three
 to four inches of snow are forecast for Ketchum by tomorrow morning
 and up to nine inches possible for Titus and the northern sector.

 Winds will be a key factor, coming from the southwest 20 to 30 mph and
 stronger gusts. Blowing snow will create blizzard conditions. Soldier
 Mtn weather station is operating (Special thanks to the ski area & cat
 ski operations!)and we expect to see some strong wind speeds there.

 Temperatures will warm some at upper elevations, 10 to 15 degrees
 expected today. This is not as much as originally forecast, but lower
 elevations could see temperatures near 30 degrees.