SUNDAY, DECEMBER 31st

Good morning, this is Scott Schmidt with your Gallatin National Forest
Avalanche Advisory issued on Sunday, December 31st, at 7:30 am.  Today's
advisory is sponsored by Polaris Industries and Team Bozeman.  As always,
this advisory does not apply to operating ski areas.

                CURRENT CONDITIONS AND WEATHER DISCUSSION:

More snow!  Most mountain locations around our area picked up an additional
2 to 4 inches of light, fluffy powder yesterday.  The big winners were the
northern mountains with 4 additional inches in the Bridger's and up to a
foot in the northern Gallatin Range.  Ridge-top winds were 5 ? 15 mph in
most mountain locations with the exception of the Bridger Range where ridge
winds where a steady 15 ? 40 mph for most of the day.  Today will be one of
those blue bird powder days they put in the magazines.  Skies will clear
with daytime highs around 30 degrees and ridge-top winds will be from the
west at 10 ? 15 mph.

                    SNOWPACK AND AVALANCHE DISCUSSION:

The Lionhead area near West Yellowstone, the mountains around Cooke City,
the southern Madison, southern Gallatin and Washburn Ranges:

I was down in the Lionhead area yesterday where thing are still pretty
interesting to say the least.  My partner and I dug a snow pit near the
ridge crest.  The snowpack in this area was a little over three feet deep
and the snow at the base was so weak we could not isolate a column to do
stability tests.  This instability resulted in a significant avalanche
cycle that probably occurred mid-week and was the result of wind loading.
Unfortunately the unstable snow is not confined to steep wind-loaded areas.
We saw the remains of a large avalanche on a low angle slope that appeared
to be snowmobile trigger.  The fracture line ran through a lightly treed
area approximately 300 feet below the ridge crest on a non-wind loaded part
of the slope.  Just to give you some perspective, Doug learned to high-mark
on this slope so you know it can't be to steep.  Just a little ways down
the ridge we got another good indication of the general snowpack
instability that is plaguing our southern regions. Sometime in the past
couple of days a moose tried crossing a slope with an average slope-angle
of 33 degrees.  As he or she crossed a rollover on the slope it avalanched
taking the moose with it.  Fortunately it appears the moose was on the edge
of the avalanche and was kicked out of the slide after going for a bit of a
ride.  The tracks popped out of the debris about 2/3rds of the way down the
slope and made a bee-line for the trees.  You think we got it tough getting
caught in avalanches while we're trying to have fun.  How would you like to
have to assess the avalanche danger just trying to get your dinner?  Given
the recent avalanche cycle and the moose-triggered avalanches I continue to
consider the avalanche danger to be CONSIDERABLE on all slopes in the
southern region.

The northern Gallatin and northern Madison Ranges and the Bridger Range:

The snow that fell in the northern regions had an average density of 8%.
With most areas only receiving 6 to 8 inches of snow and light winds, the
overall load on the snowpack has not increased much.  Reports from both the
Big Sky and Bridger Bowl ski patrols indicate the new snow is bonding well
and is not causing much of an avalanche problem for either area.  There may
be a couple of exceptions you'll want to pay attention to.  Some areas in
the northern Gallatin Range picked more then an inch of water in the past
two days.  This translates into a foot or more of snow.  With the variable
snowpack strength that exists in the northern areas I would tread
cautiously in these areas until you get a feel for the stability of the
snowpack under the new load. The other exception may be ridge-top wind
loading in the Bridger Range due to yesterday's winds.  For today, I
consider the avalanche danger to be MODERATE on all slopes in the northern
mountains.

END