Good morning. This is Mark Staples with the Gallatin National Forest Avalanche Advisory issued on Thursday, January 8, at 7:30 a.m. Today’s advisory is sponsored by Montana Import Group in partnership with the Friends of the Avalanche Center. This advisory does not apply to operating ski areas.
Many valley locations remained cold yesterday, but mountain temperatures were pushing 40 F and this morning were in the high 20s F. Winds increased a little last night but lessened this morning to 15-25 mph from the W. Today a cold front just east Bozeman will keep temperatures from climbing much higher than they are this morning. Winds should blow 15-25 mph and shift to a NW direction.
Bridger Range Gallatin Range Madison Range
Lionhead area near West Yellowstone Cooke City
The odds of triggering an avalanche have dropped since just two days ago when heavy snowfall spiked the avalanche danger. The snowpack was not producing many avalanches prior to this storm and did not produce as many avalanches as we expected following the storm.
We thought this new snow fell on a widespread layer of surface hoar, but it appears to be an issue in isolated areas versus being a widespread problem. On Tuesday Doug skied just north of Big Sky in Beehive Basin, and I rode just south of Big Sky on Buck Ridge. On most slopes the surface hoar was either not present or unreactive in stability tests. I did see a few avalanches and found the surface hoar on one slope (photo1, photo2). The heavy load of new snow also stressed facets in the bottom foot of the snowpack (video, photo) on some slopes.
What does all this mean? The snowpack overall appears to have supported this recent load of snow fairly well. Weak layers in the snowpack either do not exist or have been mostly unreactive. To be sure, dig a snowpit and perform at least one stability test. Look for a weak layer just under the new snow 1-3 feet deep. If the snowpack is relatively thin (less than 3 feet deep) assess facets in the bottom foot. Many stable slopes exist especially in the Bridger Range and near Cooke City.
It’s tricky today because pockets of instability exist where triggering an avalanche will be easy to do. Unfortunately there’s no clear pattern where these pockets exist. With heightened avalanche conditions in these specific places, the avalanche danger is rated MODERATE.
Heads up: Just outside the advisory area yesterday in the Absaroka Range south of Livingston, skiers spotted many many recent avalanches near the Mill Creek drainage; a sign of very unstable conditions that may persist for a long time.
I 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.
Companion Rescue Clinic, Bozeman, Friday eve and Saturday 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.
Companion Rescue Clinic, Cooke City, 9 a.m.-3 p.m. on Sunday, January 18. More details and registration: https://www.ticketriver.com/event/13990
Introduction to Avalanches with Field Course, MSU Bozeman, evening lectures 7-9:30 p.m. Wednesday and Thursday, January 21 and 22, with an all-day field session on Saturday or Sunday (your choice). Get more information and register here: https://www.ticketriver.com/event/13090
Advanced Avalanche Workshop with Field Course, MSU Bozeman, evening lectures 7-9:30 p.m. Wednesday and Thursday, January 28 and 29, with an all-day field session on Saturday. Get more information and register here: https://www.ticketriver.com/event/12445
The Friends of the Avalanche Center and Montana Ale Works are hosting an Avalanche Forecaster’s Beer Social Fundraiser the evening of January 27th. Get more information and buy tickets here: https://www.ticketriver.com/event/14010