Good morning. This is Ian Hoyer with the Gallatin National Forest Avalanche Forecast on Friday, March 4th, at 7:00 a.m. This information is sponsored by Blitz Motorsports and Yamaha and Grizzly Outfitters. This forecast does not apply to operating ski areas.
Mountain temperatures dropped below freezing overnight and are in the high 20s F this morning. There is no new snow to report. Winds are 10-20 mph out of the south and west, with gusts of 30-40 mph. Temperatures will rise into the 30s F today. A cold front this afternoon will bring decreasing temperatures, increasing clouds, winds shifting to the north and east, and light snowfall. 1-4” of new snow are possible by tomorrow morning, favoring the Big Sky and Cooke City areas.
Triggering large wet and dry avalanches are both concerns today. Yesterday, 3 avalanches broke on weak layers 1-2 ft deep on east aspects in Republic Creek and ran a couple hundred vertical feet (photo, photo, details). A skier triggered and was caught in an avalanche on Tuesday on this same weak layer near Goose Creek (photos and details). You could trigger a similar slide today. Temperatures will rise well above freezing after a poor refreeze overnight. This means you could also trigger wet loose avalanches, especially on sunny slopes. Increasing clouds should keep conditions from deteriorating too much, but even a small loose slide can be an issue in consequential terrain. The avalanche danger is rated MODERATE.
While the snow surface refroze last night, temperatures only dropped below freezing for a couple hours and will warm quickly this morning. A number of small wet loose avalanches were reported yesterday (avalanche log). Temperatures will be a little cooler and skies cloudier today, but wet snow remains the primary concern. Mostly these will be small surface slides, but in some places there may be unfrozen wet snow underneath a surface crust that could break in a larger avalanche. Avoid steep slopes that are wet more than a few inches below the surface. Triggering a slide on dry weak layers in top 1.5 ft of the snowpack is less likely, but it’s still worth double checking to make sure they aren’t unstable. For today, the avalanche danger is MODERATE.
With more moderate temperatures and increasing clouds any wet snow concerns will remain limited. Yesterday at Lionhead, Doug and I saw a few small wet point releases and a recent wind slab (photo, photo). These are the primary concerns today as well. Pay attention to wet snow beneath your feet and to any wind slabs that haven’t bonded, especially if you’re going to ride in highly exposed terrain. Weak layers remain in the upper snowpack that will be an issue as it starts snowing again (video, video). Overall, large avalanches are unlikely today and the avalanche danger is LOW.
Upcoming Education Opportunities
See our education calendar for an up-to-date list of all local classes. Here are a few select upcoming events.
Today! Companion Rescue Clinic with the Bozeman Splitfest. Information and registration HERE.
Every Saturday near Cooke City, 10 a.m.-3 p.m. FREE snowpack update and transceiver/rescue training. Stop by for 20 minutes or more at the Round Lake Warming Hut.
Daves Zinn’s latest article, Understanding what digital slopes angle maps can (and can’t) tell you, is a great read for anyone using apps to identify avalanche terrain.