Good morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Sunday, March 31st at 7:00 a.m. Today’s forecast is sponsored by Avalanche Alliance and Gallatin County Sheriff Search and Rescue. This forecast does not apply to operating ski areas.
Last night the Bridger Range received 2-3” of new snow, and West Yellowstone and Cooke City got 1-2” with none elsewhere. Winds have been southerly to west-northwest at 0-15 mph with gusts of 5-20 mph. This morning temperatures are 20s F. Today, temperatures will reach low to mid-30s F, and wind will be north-northeast at 5-10 mph before increasing to 10-20 mph this afternoon. Mostly cloudy skies will accompany a few snow showers, and by tomorrow morning the mountains could get 1-3” of snow.
All Regions
Today you can trigger avalanches within or below the snow that fell over the last week, or avalanches that break many feet deeper on weak layers at the bottom of the snowpack.
Yesterday in the Lionhead area near West Yellowstone a pow surfer (snowboarder without bindings) triggered and was partially buried in an avalanche that appeared to break below last week’s snow (photo). Avalanches are possible where the recent snow was drifted into thicker slabs (photo), or where it buried new weak layers. Unstable drifts are slightly more likely near Island Park where winds were strongest and the most snow fell. On Friday in the Taylor Fork I found a weak layer buried one foot deep which could cause the recent snow and wind-drifts to be unstable (video). Identify and avoid steep slopes with recently formed drifts. Before getting onto any steep slope, dig down a couple feet to look for potential weak layers and assess the stability of the recent snow.
Yesterday in Hyalite we saw a recent avalanche that broke 2-6' deep on weak snow at the bottom of the snowpack (photos, video). Another 2-4' deep avalanche occurred on Mt. Blackmore during the same timeframe (photos). These show the lingering possibility for a person to trigger a similar very large avalanche. While these massive slides have become less likely compared to earlier in the winter, they have large consequences and require thoughtful terrain selection. If you ride or cross steep slopes, choose slopes that are not heavily wind-loaded and without trees, rocks, cliffs or gullies that would increase the chances of being injured or killed if you were caught in a slide.
Cloudy skies today should prevent the snow from getting wet, and wet snow avalanches are unlikely. If the sun does show, be on the lookout for loose wet avalanches on steep slopes that receive direct sun.
Today human-triggered avalanches are possible and avalanche danger is MODERATE throughout the forecast area.
If you get out please submit an observation. It does not need to be technical. Did you see any avalanches? How much snow is on the ground? Was the wind moving snow? Simple observations are incredibly valuable. You can also contact us by email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).
Upcoming Avalanche Education and Events
Hyalite Road Closure: The gate at the bottom of the Hyalite canyon will be locked at 8:00 PM Tonight! Please be sure to exit the canyon before the gate is locked. The road closure applies to ALL MOTORIZED VEHICLES until the morning of May 16.
Events and Education Calendar.
Loss in the Outdoors is a support group for those affected by loss and grief related to outdoor pursuits. Check out the link for more information.
If you have a few minutes, take a survey on how you interpreting avalanche forecast information in hopes of improving avalanche forecasting methods.