Good morning. This is Mark Staples with the Gallatin National Forest Avalanche Advisory issued on Saturday, February 7, at 7:30 a.m. Grizzly Outfitters in partnership with the Friends of the Avalanche Center sponsors today’s advisory. This advisory does not apply to operating ski areas.
This morning warm and windy weather continued with temperatures in the 30s F and winds averaging 25 mph gusting 40-70 mph from the S and SW. It looked like some snow had started falling this morning near Big Sky at 5 a.m. Today temperatures should only rise a degree or two and may cool a bit this afternoon. Strong winds will continue today shifting a little more westerly. 3-4 inches of snow should fall near West Yellowstone and Cooke City, a few inches near Big Sky, and a trace of snow near Bozeman.
Bridger Range Madison Range Gallatin Range
Lionhead area near West Yellowstone Cooke City
Fresh wind slabs continue to be the primary avalanche problem (wind video, wind transport photo). With more strong winds and snowfall today, these wind slabs will remain easy to trigger. Yesterday near Cooke City, Eric and his partners observed several wind slabs that had released naturally including one large one that produced debris 10 feet deep (photo). My partners and I found a much smaller one near Buck Ridge just south of Big Sky on Thursday (photo).
Fortunately wind slabs and wind loaded slopes are easy to identify and avoid. A secondary and trickier problem is buried surface hoar. It does not exist in the Bridger Range. Eric didn’t find it near Cooke City (video), and I didn’t find it along Buck Ridge near Big Sky. However, a group found it in the Portal Creek drainage of the northern Gallatin Range on Thursday, and Doug found it on Lionhead near West Yellowstone on Tuesday (video).
This season surface hoar has formed many times and sometimes and in some places survived and been buried, but it hasn’t caused much avalanche activity. This trend may continue, but surface hoar is a notorious weak layer that is worth looking for it. Quickly dig only 2 feet deep making a smooth wall and look for a stripe of surface hoar (photo). If you see it, perform a quick ECT (see how here) focusing on whether or not it propagates a crack in the buried surface hoar layer.
Today with more snow coming and strong winds continuing to build wind slabs and drifts, the avalanche danger is rated CONSIDERABLE on wind loaded slopes. Non wind loaded slopes have a MODERATE danger.
AN ARTICLE FOR PARENTS
Are you a parent of a kid that skis at a ski area? Do you know if they head out-of-bounds into the sidecountry? Doug’s article “Sidecountry”: Rated R sheds light onto the seriousness of skiing the uncontrolled and unpatrolled slopes next to a ski area.
Eric 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.
KING AND QUEEN OF THE RIDGE
Saturday, February 14th is the 13th Annual King and Queen of the Ridge Hike/Ski-a-thon fundraiser at Bridger Bowl to support avalanche education in southwest Montana. Collect pledges for each lap of hiking to the ridge and skiing back down. 100% of the proceeds go to the Friends of Gallatin National Forest Avalanche Center. Hike as an individual or form a team of your workmates or playmates or family! Prizes are awarded for Team and Individual categories. Make a Pledge. Sign Up and More Info.
AVALANCHE EDUCATION and EVENTS
Take a look at our Education Calendar for all classes being offered.
Woman's 1-hour Avalanche Awareness, Bozeman, REI, 6:30 p.m., Wednesday, February 11.
Companion Rescue Clinic, Bozeman, REI, 6-8 p.m., Friday, February 20 and 10 a.m.-2 p.m. on Saturday, February 21 (field location TBD). Pre-registration is required: www.rei.com/stores/bozeman.html
1-hour Avalanche Awareness, West Yellowstone, Holiday Inn, 7 p.m., Saturday, February 21.