Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Saturday, February 5, at 7:30 a.m. Gallatin County Search and Rescue, in cooperation with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
A moist NW flow has delivered a welcomed shot of snow to southwest Montana. Since yesterday morning, 11 inches of snow has fallen in the mountains around Cooke City; 5-6 inches has fallen in the mountains around Bozeman and Big Sky and 3-4 inches has fallen around West Yellowstone. Winds are blowing out of the W-NW at 20-30 mph with ridgetop gusts reaching into the 40s. Temperatures are in the high teens to low 20s and will warm into the mid 30s by this afternoon. Snow will continue through the day with an additional 3-6 inches possible by this evening. Southwest Montana will see a break in the weather tonight, but another round of snow will impact our region Sunday night into Monday.
The Bridger, Madison and Gallatin Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
Mud season usually starts around April or May in Montana, but it seems that it has arrived in early February this year. Yesterday, my partners and I skied near Flathead Pass in the northern Bridger Range and got an unexpected dose of wet weather (rain) and yes - mud; not quite what we were expecting. Fortunately, rain levels stayed below 6,000 ft. We did find stable conditions on upper elevation slopes.
Today, wind loaded slopes will be the primary avalanche concern. Upper elevation slopes favored by W-NW winds will be the most likely to produce a slide but mid-elevation, cross loaded slopes may produce avalanches as well. Recently formed wind drifts sitting upon surface hoar, near surface facets, or lower density snow will likely be sensitive to the weight of a skier or rider. Look for visual clues like fat, rounded & pillow like formations that indicate recent wind loading. Visualizing shooting cracks or recent avalanche activity are prime indicators the snowpack is unstable. Avoiding steep, wind loaded slopes today will be the best way to avoid triggering a slide.
A secondary concern is any steep slope with a shallow snopack. Upper elevation, rocky terrain will be the most likely areas to find weak, faceted snow. Many of these shallow areas may have been weak, but not unstable prior to this latest storm (video). However, the weight of new and windblown snow may be enough to stress these weaker areas into failure. If you are able to push your ski pole to the ground, finding another slope to ride will likely be in your best interest.
Today, continued snow and wind will make human triggered avalanches likely on all wind loaded slopes where the avalanche danger is rated CONSIDERABLE. Slopes that have not received a wind load have a MODERATE avalanche danger.
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.
9th ANNUAL KING AND QUEEN OF THE RIDGE
The 9th Annual King and Queen of the Ridge will be held at Bridger Bowl on Saturday, February 12. ALL proceeds go to the Friends of the Avalanche Center who use the money to promote avalanche education in southwest Montana. You can help raise money to continue this education in two ways: 1). Get pledges and hike the ridge. You don’t have to do 20 laps – you can get flat pledges and hike just once! Or you can test your mettle and try and break John Yarington’s record of 29 laps in 5 hours. 2). Sponsor someone. If you don’t have someone to sponsor, consider sponsoring the GNFAC since we’ll be hiking for dollars. Go to http://bridgerbowl.com/events/view_event/81/ for more information and registration forms.
Avalanche Education
February 9 in Bozeman
Lucas Zukiewicz-NRCS, from the Montana Snow Survey will present information about the SNOTEL system in Montana, and how to gather and interpret SNOTEL information for backcountry avalanche conditions and travel planning. This free lecture will be held at the REI on 19th Street, from 6:30 p.m. to 8:00 p.m. More info can be found at: http://www.rei.com/event/16591/session/20368
February 12 and 13 in Cooke City
Avalanche Workshop for Snowmobilers and Skiers – Lectures on Saturday 12 p.m. – 4:30 p.m.
field session on Sunday 9 a.m. – 3 p.m. ADVANCED REGISTRATION REQUIRED (more information and registration)
For additional information and a listing of other avalanche classes, go to: http://www.mtavalanche.com/workshops/calendar