Good morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Thursday, February 3, at 7:30 a.m. Alpine Orthopedics, in cooperation with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
Under clear skies, mountain temperatures range from 12 to 20 degrees above zero. West to northwest winds have increased from 10-15 mph yesterday morning to 20-30 mph. They will get even stronger this afternoon as the high pressure ridge flattens and clouds appear. Tonight, temperatures will fall into the low teens and scattered snowfall will measure a trace to one inch by morning. A strong northwest flow builds tomorrow and the weather models show a snowy weekend. My fingers are crossed.
The Bridger, Madison and Gallatin Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The winds have not been confined to the ridgetops. Steady speeds of 20-30 mph are blowing downhill and across slopes at mid and lower elevations. In the last 24 hours wind drifts formed in gullies and on small terrain features which could be triggered today. I don’t expect these wind pillows to be very big since there’s not much loose snow to blow around, but even shallow slabs can fracture and carry us into terrain traps.
There are no consistent weak layers buried in our snowpack. We have very good snow stability even though thinner slopes have lots of facets (video). Mark and I found this on Wheeler Mountain in the northern Gallatin Range on Tuesday. Without a big load of snow, these slopes would be difficult to trigger. Eric found stable conditions yesterday in Dudley Creek in the northern Madison Range. He also saw an old avalanche from 12 days ago; weak, faceted snow formed around a rock band and then got loaded to its breaking point by new and windblown snow (picture).
It looks like we’re poised to bury the surface weakness’s that formed during the cold, clear weather this week. Surface hoar and near surface facets are on many slopes. Some may already be buried under new wind drifts. If the predicted snow falls, then this layer will be preserved and quickly become unstable.
Recently formed wind drifts are today’s primary avalanche concern. Throughout our advisory area the danger is rated MODERATE on all wind-loaded slopes and LOW everywhere else.
Mark 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