GNFAC Avalanche Forecast for Mon Feb 1, 2016

Not the Current Forecast

Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Monday, February 1, at 7:00 AM. Today’s advisory is sponsored by Edward Jones and Bridger Bowl. This advisory does not apply to operating ski areas.


Mountain Weather

A weak northwest flow is producing cold and unsettled conditions across southwest Montana. Overnight the mountains picked up a trace to one inch of snow. This morning temperatures range from five below zero in Cooke City to the single digits above zero elsewhere and winds are blowing 5-15 mph out of the NW. Today, temps will struggle to warm into the low teens F and winds will remain light out of NW. Skies will be partly to mostly cloudy and there’s a slight chance of mountain snow showers this afternoon. A northwest flow will keep conditions unsettled over the next 24 hours, but no major snow accumulation is expected.


Snowpack and Avalanche Discussion

Bridger Range   Madison Range   Gallatin Range  

Lionhead area near West Yellowstone   Cooke City

January was a good snow month for southwest Montana. Most Snotel sites in our area recorded around 4” of SWE for the month - Brackett Creek in the Bridger Range topped the charts at 4.7”. This consistent snowfall has helped the snowpack more than it has hurt.

Yesterday, Doug and I rode in the Lionhead area near West Yellowstone and observed less avalanche activity than expected. The Lionhead received close to a foot of snow totaling over 1” of SWE in a 24-hour period (Friday night), which is often enough to tip the scales and produce avalanches. This is a positive indicator that the snowpack is gradually getting stronger.

Strengthening aside, multiple avalanche problems continue to linger in the snowpack. The primary concern is wind loaded slopes. Strong winds out of the west-southwest accompanied Friday night’s storm, which produced dense wind slabs on leeward slopes (video). These wind slabs have begun to stabilize, but still hold the potential to fail under the weight of a skier or rider. While not all wind loaded slopes will produce avalanches, I still recommend avoiding any steep slope with wind drifted snow.

Faceted layers buried mid-pack and near the ground also remain a concern. These layers are slowly gaining strength, but continue to produce unstable results in stability tests along with the occasional avalanche (photo). Alex made a good video in the Bridger Range on Friday describing this problem (video). Avoiding steep, rocky terrain where the snowpack is shallow and weak will be the best way to avoid triggering a slide on deeper layers.

Today, multiple problems in the snowpack make human triggered avalanches possible and the avalanche danger is rated MODERATE.

Doug will issue the next advisory tomorrow morning by 7:30 a.m. If you have any snowpack or avalanche observations to share, drop us a line at mtavalanche@gmail.com or leave a message at 587-6984.


EVENTS and AVALANCHE EDUCATION

A complete calendar of classes can be found HERE.

February 3rd Bozeman: 1hr Avalanche Awareness, Best Western Gran Tree Inn, 7:30-9:00 p.m.

February 6th West Yellowstone: 1hr Avalanche Awareness, West Yellowstone Holiday Inn, 7-8 pm

February 9th Bozeman: 1hr Avalanche Awareness for snowmobilers, Summit Motorsports, 6-7 pm

EVENT at BRIDGER BOWL: February 6, King and Queen of the Ridge. A day of hiking and skiing the Ridge as a fundraiser for the Friends of the Avalanche Center. Teams and individuals are welcome! More info here: http://bridgerbowl.com/event/king-and-queen-of-the-ridge