Good Morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Wednesday, February 8th at 7:15 a.m. Today’s advisory is sponsored by Wisetail and Gallatin County Search and Rescue. This advisory does not apply to operating ski areas.
AVALANCHE WARNING
We are continuing a Backcountry Avalanche Warning for the mountains around Cooke City. Continued snowfall and strong winds have created a HIGH avalanche danger on all slopes. Natural and human triggered avalanches are likely today. Avalanche terrain and avalanche runout zones should be avoided.
In the last 24 hours 5-7” of snow fell in the northern mountains and Cooke City with 3-5” around West Yellowstone. Winds decreased yesterday but picked up this morning to 20-25 mph out of the west with gusts of 40-60 mph. Under cloudy skies mountain temperatures are in the mid-teens. Another inch may fall this morning with 4-6” more tonight. Today, winds will remain west and temperatures will reach the lower 20s under mostly cloudy skies.
Cooke City
Cooke City got another 6+” of snow measuring .6” of SWE (snow water equivalent) totaling 5.6” of SWE since Friday, a hefty amount of weight. Winds were moderate yesterday, but today gusts of 40 mph will be loading many slopes. Widespread collapses (whumphs) were reported by a ski guide yesterday, and another skier had propagation in his stability tests 2’ under the surface. Steady snowfall, erratic winds, buried weak layers of surface hoar and facets, and most importantly, natural and human triggered avalanche activity on Sunday indicate dangerous avalanche conditions will continue (photos page). For today, the avalanche danger is rated HIGH on all slopes.
Southern Madison Range Southern Gallatin Range Lionhead area near West Yellowstone
The snowfall in the southern mountains has tapered off although winds have picked up. Storm totals since Friday are 3.1” SWE measuring less than two feet of settled snow. Wind speeds at the Taylor Fork weather station are measuring gusts of 60 mph out of the west. Near the weather station on Sunday I saw the debris of a natural avalanche from wind-loading. Alex was in Teepee Basin on Monday and found new snow being blown around and was concerned about buried weak layers of surface hoar and facets which he describes in his video. Given the new snow, strong winds and buried weak layers, the avalanche danger is rated HIGH on all wind-loaded slopes and CONSIDERABLE on all others. Be conservative today since triggering avalanches is likely in all avalanche terrain.
Bridger Range Northern Madison Range Northern Gallatin Range
Last night 5-7” of snow fell from the Bridger Range to Big Sky for a total of 8-12” in the last 48 hours. Yesterday, Eric and his partner went to the northern Bridger Range after a road closure turned them around on their drive to Cooke City. They sledded and skied into The Throne and found calm winds, powder and mostly stable conditions which he shows us in this video. The snowpack still has a weak layer of facets at the ground, but it will take a larger load to get it to avalanche. The ridgetop winds have picked up and have touched 60 mph in Hyalite and around Big Sky. For today, the avalanche danger is rated CONSIDERABLE on all wind-loaded slopes and MODERATE on all others.
Eric will issue the next advisory tomorrow morning by 7:30 a.m.
We rely on your field observations. Send us an email with simple weather and snowpack information along the lines of what you might share with your friends: How much new snow? Was the skiing/riding any good? Did you see any avalanches or signs of instability? Was snow blowing at the ridgelines? If you have snowpit or test data we'll take that too, but this core info is super helpful! Email us at mtavalanche@gmail.com or leave a message at 406-587-6984.
Beacon Training Park at Beall: Open and free to the public for avalanche beacon practice seven days a week from 9 a.m. to 8 p.m., southeast corner of Beall Park in Bozeman.
COOKE CITY
Weekly rescue training and snowpack update, 6:30-7:30 p.m., Cooke City Super 8 on Friday, Lulu Pass Road for field location Saturday (Look for the yellow sign).
BOZEMAN
TONIGHT! 1-hr Avalanche Awareness, 7-8 p.m., Roskie Hall, Montana State University.
February 10 and 11, Companion Rescue Clinic, REI and field day, more info and register here.
WEST YELLOWSTONE
February 11, 1-hr Avalanche Awareness, 7-8 p.m., West Yellowstone Holiday Inn.
ENNIS
February 17, 1-hr Avalanche Awareness, 6-7 p.m., Madison Valley Rural Fire Department Station 1.