Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Sunday, February 8, at 7:30 a.m. Edward Jones and Bozeman Ski Guide sponsors today’s advisory. This advisory does not apply to operating ski areas.
Over the past 24 hours the mountains near West Yellowstone and Cooke City picked up 3-5 inches of heavy, dense snow. The mountains near Big Sky including the northern Gallatin Range picked up 1-2 inches, while the Bridger Range remained dry. This morning, mountain temperatures range from the upper 20s to low 30s F and winds are blowing 15-25 mph out of W-SW with gusts reaching close to 40 mph. Today, temperatures will warm into the mid to upper 30s F under clearing skies. Winds will gradually decrease throughout the day, but will continue to blow 15-25 out of the W. No precipitation is expected over the next 24 hours.
Southern Madison Range Southern Gallatin Range
Lionhead area near West Yellowstone Cooke City
The southern mountains picked up 3-5 inches of heavy, dense snow yesterday. Fisher Creek Snotel Site near Cooke City recorded .7 inches of SWE (snow water equivalent) over the past 24 hours while Carrot Basing Snotel Site in the southern Madison Range picked up .6 inches of SWE. This fresh snow didn't add a ton of weight to the snowpack, but it did provide plenty of fresh ammunition for wind slabs (photo), which will be today’s primary avalanche problem.
Yesterday, Mark and I rode in Teepee Creek in the southern Madison Range and observed lots of fresh snow being pushed around by gusty west-southwest winds. Other riders in the area observed a few small natural avalanches that occurred in steep, wind loaded terrain. I also observed fresh avalanche activity on wind loaded slopes in the mountains around Cooke City on Friday (photo). Today, fresh wind slabs will remain sensitive to human triggers.
A secondary and trickier problem is a layer buried surface hoar 1-2 feet deep. Yesterday, Mark and I found this layer on a north facing slope in Teepee Creek. Doug also found this layer in the Lionhead area last Tuesday (video). This layer does not exist on all slopes (video), but should be looked for and assessed before committing to stepper terrain.
Today, fresh snow and strong winds will make human triggered avalanches likely on wind loaded slopes which have a CONSIDERABLE avalanche danger. Non-wind loaded slopes have a MODERATE avalanche danger.
Bridger Range Northern Madison Range
Northern Gallatin Range
Minimal snow in the mountains around Bozeman and Big Sky will make fresh wind slabs less of a problem in these areas. However, an inch or two few of new snow combined with blustery west winds will form small wind slabs in isolated areas. Although wind slabs won’t be quite as large and widespread in the northern mountains, it’s still a good idea to carefully analyze your terrain choices and avoid any slope where fresh wind slabs may be lurking.
Outside of wind loaded slopes, the snowpack is mostly strong and stable. There are few buried weak layers to keep an eye out for, as one group of skiers found in Portal Creek on Thursday. Although buried weak layers are not widespread in the north, it’s always a good idea to put the shovel in the snow before center punching a steep line.
Today, human triggered avalanches are possible on wind loaded slopes or slopes steeper than 35 degrees which have a MODERATE avalanche danger. All other slopes have a LOW avalanche danger.
Wet Snow Avalanche Danger
Temperatures are at or just below freezing this morning. This will quickly change as the day progresses. Above freezing temperatures and the potential for increased sun today will make wet loose avalanches possible on steep, sun exposed slopes. Roller balls and point releases are bull’s eye information the snowpack is losing strength. Avoid slopes where signs of instability are present. Today, the wet snow avalanche danger will rise to MODERATE on sun exposed slopes.
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.
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.
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.