GNFAC Avalanche Forecast for Sun Jan 19, 2020

Not the Current Forecast

Good Morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Sunday, January 19th at 7:00 a.m. Today’s forecast is sponsored by Grizzly Outfitters and Cooke City Super 8/Bearclaw Bob’s. This forecast does not apply to operating ski areas.

Mountain Weather

Last night the mountains got 1-3” of low density snow. This morning temperatures are teens to low 20s F and wind is west-southwest at 5-15 mph with gusts of 20-30 mph. Today will be sunny with temperatures in the 20s F and westerly wind at 10-20 mph. Snow is expected early Tuesday with more through the weekend.

Snowpack and Avalanche Discussion

Although not in our advisory area there were two people killed by avalanches yesterday, a snowmobiler in Utah and an ice climber in Colorado. These were the ninth and tenth fatalities this month (12 this season). We are deeply saddened by each of these events. Incidents are frequent this time of year and we lose sleep over preventing more. Throughout the western U.S. the snowpack has buried weak layers that have been overloaded by storms since the start of 2020. Head out and have fun, but ride safe. Keep objectives mellow, constantly evaluate your exposure to avalanche terrain and commit to come home alive.

In southwest Montana we have seen natural and human triggered avalanches 15 of the last 18 days (activity log). Yesterday Doug visited a massive avalanche on Mt. Henderson near Cooke City. It was up to 15 feet deep and triggered by a snowmobiler on Thursday (video). This and an avalanche on Buck Ridge a couple weeks ago (details) are two of the three largest crowns Doug has seen in person (he’s been around for years, at least 25). Both were triggered by snowmobilers, and on Buck Ridge three people were caught and luckily uninjured.

Yesterday a snowmobiler triggered an avalanche in the Taylor Fork (photo), and a large natural avalanche broke from a cornice fall south of Saddle Peak (photo). Near West Yellowstone two separate groups were surprised that they could get stability tests to propagate on sugary snow deep in the snowpack.

Avalanche conditions are heightened and large avalanches can be triggered with severe consequences. These big slides are getting more difficult to trigger as weak layers get buried deeper, but as Doug says in his video, “they will kill you”. If you go into avalanche terrain you have to collect a lot of data and be 99.9% sure of good stability. Large avalanches are possible to trigger and avalanche danger is MODERATE.

Yesterday there were three skier triggered avalanches reported in the northern Gallatin Range (details, details). One on Flanders Mountain was very large and took out the skin track of another group (details). The snowpack in and near Hyalite was generally stable, but yesterday’s activity is a sign that recent wind-drifted snow has activated buried weak layers. Avalanches are possible to trigger on wind loaded slopes and they can break wide on buried persistent weak layers. On non-wind loaded slopes avalanches are less likely. Carefully evaluate the snowpack and terrain. Danger is MODERATE on wind loaded slopes and LOW on other slopes.

If you get out, please send us your observations no matter how brief. You can fill out an observation form, email us (, leave a VM at 406-587-6984, or Instagram (#gnfacobs).

Upcoming Avalanche Education and Events

Our education calendar is full of awareness lectures and field courses. Check it out and plan to attend one or two: Events and Education Calendar.


Every Friday and Saturday, Snowpack Update and Rescue Training. Friday, 6:30-7:30 p.m. at the Soda Butte Lodge. Saturday anytime between 10-2 @ Round Lake.


January 27, Avalanche Information and Demonstration Table, 10 a.m. to 12 p.m. at Montana Science Center.

January 29, GNFAC Forecaster Chat: Avalanche Myth Busters, 6-8 p.m. at Uphill Pursuits.

January 31, Women’s Only Companion Rescue Clinic, 6 - 8 pm at REI followed by a field day February 1. More info and Register Here.

February 1, King and Queen of the Ridge at Bridger Bowl (fundraiser). This is the Friends of the Avalanche Center’s second biggest fundraiser of the year. Come on out and help us raise money by hiking and skiing laps on the ridge. Prizes, camaraderie and a good time is guaranteed. Register with Bridger to hike in the event, and create a pledge page to raise funds with your Ridge laps.


January 29 and 30, Introduction to Avalanche w/ Field Course, evenings of January 29 & 30 plus a field day February 1. Snowmobile specific field day offered February 2. More Info and Register Here.


January 25, 1-hr Avalanche Awareness, 7-8 p.m. at West Yellowstone Holiday Inn.

February 1, 1-hr Avalanche Awareness, 7-8 p.m. at West Yellowstone Holiday Inn.


January 28, 1-hr Avalanche Awareness, 6-7 p.m. Carroll College.


January 30, Introduction to Avalanche w/ Field Course, evening of January 30 plus a field day February 2. More info and Register Here.

The Last Word

Tomorrow night, January 20th from 4-8pm at Beehive Basin Brewery, join the YC and Big Sky Ski Patrols to support the Darren Johnson memorial fund. Darren was a ski patroller at the Yellowstone Club who was killed in an avalanche on January 19th, 2016. The memorial fund gives scholarships for patrollers to attend the National Avalanche School.

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