Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Monday, January 5, at 7:30 a.m. Today’s advisory is sponsored by Yellowstone Club Community Foundation in partnership with the Friends of the Avalanche Center. This advisory does not apply to operating ski areas.
AVALANCHE WARNING
We are issuing a Backcountry Avalanche Warning for the Bridger Range, Gallatin Range, Madison Range, Lionhead area near West Yellowstone and Cooke City. Heavy snowfall and strong winds will create widespread instability and the avalanche danger is rated HIGH on all slopes. Very dangerous avalanche conditions exist and both natural and human triggered avalanches will be likely. Travel in avalanche terrain and avalanche runout zones should be avoided.
Over the past 24 hours the mountains near Cooke City have picked up 15” of new snow. The mountains near West Yellowstone and Big Sky have picked up 10-12” while the mountains near Bozeman have picked up 4-8”. Currently, it’s still snowing hard with the exception of the Bridger Range where snowfall has briefly let up. Temperatures are on the rise with most mountain locations reading in the 20s F. Winds are strong out of the W-SW blowing 15-30 mph with upper elevation gusts reaching close to 50 mph. Today, snow will continue over the entire forecast area. The mountains near Cooke City and West Yellowstone will likely pick up 6-10” during the day while the mountains around Bozeman and Big Sky will pick up 4-6”. Light snow will continue tonight with a few more inches possible.
Bridger Range Gallatin Range Madison Range Lionhead area near West Yellowstone Cooke City
A major winter storm is impacting southwest Montana. The main concern with this storm is the higher density snow that is falling due to warmer temperatures. This heavier snow will be falling on lighter, low density snow which will create an unstable snowpack structure. This recent load will also be adding stress to a layer buried surface hoar that formed around New Year's Day (video). This surface hoar layer has been found throughout our advisory area, with the exception of the Bridger Range (video), and has the potential to produce widespread instability.
In addition to heavy snowfall, strong winds out of the W-SW will be transporting snow onto leeward slopes. Wind deposited snow will form dense wind slabs and put additional weight/stress on buried weak layers. Strong winds will continue throughout the day keeping instability on the rise.
The bottom line – Today is not the day to travel in avalanche terrain. All steep slopes and avalanche run out zones should be avoided. Natural and human triggered avalanches are likely and the avalanche danger is rated HIGH.
Doug will issue the next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations drop us a line at mtavalanche@gmail.com or call us at 587-6984.
AVALANCHE EDUATION and EVENTS
Take a look at our Education Calendar for all our classes being offered.
1-hour Avalanche Awareness for Snowmobilers, Cooke City, 6:30-8 p.m., Monday, January 5, Cooke City Community Center.
1-hour Avalanche Awareness for Snowmobilers, Billings, 6:30-8 p.m., Wednesday, January 7 at Hi-Tech Motor Sports.
Companion Rescue Clinic, Bozeman, Fri eve and Sat field, January 9 and 10, REI. Register for the class here: www.rei.com/stores/bozeman.html
1-hour Avalanche Awareness for Snowmobilers, West Yellowstone, 7 p.m., Saturday, January 10, Holiday Inn.
1-hour Avalanche Awareness, Three Forks, 7 p.m., Monday, January 12, Methodist Church Annex.
Women’s Avalanche Awareness w/ Beacon Practice, Bozeman, 6:30- 8 p.m., Tuesday, January 13, Beal Park.
1-hour Avalanche Awareness, 4 Corners, 6:30 p.m., Wednesday, January 14, GVSA Groomer Shed.
1- hour Sidecountry Avalanche Awareness, Bozeman, 6:30-8 p.m., Wednesday, January 14, REI.