This is Doug Chabot from the Gallatin National Forest Avalanche Center with an Avalanche Information Bulletin issued at 7:30 a.m. on Wednesday, December 2. Jeff King of Edward Jones in cooperation with the Friends of the Avalanche Center sponsor this bulletin. This information will be updated on Saturday morning when we begin issuing daily advisories. This advisory does not apply to operating ski areas.
Yesterday's cold front dropped temperatures and a bit of snow. Those watching the thermometer saw it plummet from the 20s to the single digits in three hours. This quick blast of snow added another 3-5 inches from Lone Peak to the Bridgers while the southern mountains got 1-2 inches. Winds are currently west to north at 10-15 mph and should remain light through Friday. Skies will become clear and sunny until Saturday when another band of snow looks on track to hit us. Daytime temperatures will reach the 20s, but dip to below zero in the evenings.
The Bridger and northern Gallatin Ranges: The snowpack in the northern Gallatin and Bridger Ranges remain
strong and can easily support the new four inches of snow. Stability tests and general observations from
these ranges continue to indicate a stable snowpack. The mountains around Bozeman are getting hit
hard by skiers and ice climbers since our early season conditions are the best
in years. Strong westerly winds Monday
night created isolated wind drifts near the ridgetops which is our lone
avalanche concern. The Madison and
southern Gallatin Ranges, including the Lionhead area near West Yellowstone and the mountains around Cooke City: The snowpack around West
Yellowstone is thin and there have not been many reports of folks skiing or
riding just yet. Further north, especially
near Lone Peak, the snow is two feet deep at 8,500 feet. Skiers touring into Beehive/Bear Basins are finding
supportable, but also weak snow. Dense
snow at the ground is keeping skiers off the rocks and dirt, but above this are
sugary facets in between ice crusts. The
slopes are mostly stable right now, but could quickly change for the worse if
we get a big storm. Video of stability tests from Sunday: http://www.youtube.com/watch?v=JHxIiJCfh2k. Isolated
wind slabs at the ridgeline are a concern.
In Middle Basin yesterday, someone ski cut 6-8 inch slabs formed during Monday
night's strong winds. If you're gonna be dumb, you
better be tough. And not
being the sharpest, Mark and I elected to put up the Cooke City weather station
yesterday when it was 2 degrees and blowing 20 mph instead of last week when it
was sunny and in the 40s. With numb fingers we got it up and working (http://bit.ly/5yXgti). Here's a picture of the site: http://www.mtavalanche.com/images/09/cooke-city-weather-station With minus 22F wind chill
chasing us, we warmed ourselves up by digging two snowpits in Fischer drainage:
one on a south and another on a north aspect. The north facing slope had
three feet of stable snow.
The south was 2 ½
feet deep and layered with sun crusts and facets which could be a problem with
a big snowstorm. Snowmobile tracks were everywhere. Brave riders over Thanksgiving hammered the
slopes with abandon and risked trashing their sleds as they weaved around and
over boulders. Thankfully, the snowpack
was deep enough, supportable enough and stable enough for folks to get out and play. But I'm
sure many parts departments saw a spike in trailing arm purchases. Mark will issue the next advisory Saturday
morning at 7:30 a.m. If you get out in
the backcountry give us a call or send us an email with your observations. You can reach us at 587-6984 or at mtavalanche@gmail.com. AVALANCHE
EDUCATION THIS WEEK Basic
Avalanche Awareness at MSU (12 Hour Course): Evening
Sessions: December 2 and 3, 2009, 7:00pm to 9:30pm, at MSU in Leon Johnson
Hall, room 339. Field
Session: December 5, 2009, 9:15am to 3:00pm, at Bridger Bowl Ski Area. Cost for the entire workshop is $25.00 ($5 each evening and $15
for the field session). Registration is not
required for the evening sessions, but is required for the field session,
which can be done at either of the evening sessions. Basic
Avalanche Awareness for Snowmobilers (12 hour Course): Bozeman: Evening Sessions: Wed and Thursday, December 2 and 3, 2009, 7-9:30
pm; Team Bozeman December 13 is an all day field session, exact location TBD. ($30
Donation) No
Registration Required. One
Hour awareness: A basic one hour awareness class will be offered at Red Line
Sports in Butte,
Dec 9th at 6 p.m. A full listing of the avalanche classes offered in
southwest Montana
can be found on the education page of our website: http://www.mtavalanche.com/education