Good morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Sunday, March 19th at 7:00 a.m. This information is sponsored by World Boards and Highline Partners. This forecast does not apply to operating ski areas.
This morning there is no new snow. Temperatures are singles to teens F. Wind has been out of the southwest at 5-20 mph with gusts of 20-30 mph. Today will be mostly sunny with temperatures reaching high 20s to low 30s F and westerly wind at 10-20 mph. The next chance for snow is tomorrow morning through Tuesday.
Yesterday near Cooke City a snowmobiler triggered a huge deep slab avalanche, and the rider was luckily unharmed (details and photos). The possibility for a person to trigger a similar avalanche on older, deep buried weak layers is the primary concern throughout our forecast area. Yesterday a skier reported a recent natural avalanche on Electric Peak which is another example of what someone could trigger today (photos and details). We have seen the majority of deep slab avalanche activity near Cooke City and West Yellowstone (Lionhead observation, video), where more snow fell over the last month, but the possibility to trigger a large, deep avalanche also exists near Bozeman and Big Sky (Hyalite Peak slide, Northern Bridgers slide).
The likelihood of avalanches has decreased since the most recent snow on Wednesday, but a person can still trigger an avalanche with large consequences. Before traveling on or underneath steep slopes, evaluate the snowpack for buried weak layers and previous wind-loading. Avoid heavily wind-loaded slopes and slopes where you suspect buried weak layers exist.
Additionally, a person can trigger avalanches of wind-drifted snow up to a couple feet deep that formed after the last snowstorm on Wednesday (Natural avalanche on Mt. Bole). These wind slabs can be harmful on their own, or trigger a larger avalanche deeper in the snowpack. Identify and avoid recently formed drifts of snow.
On slopes that receive direct sunshine, the snow surface has turned to a melt-freeze crust during the last couple days. Small wet loose slides are possible where this crust melts. Although this type of hazard has been minimal, with another sunny day it is worth keeping wet loose avalanches in mind. Additional concerns include cornices that may become weak from the hot sun and break off, and roof avalanches around buildings that have a deep winter snowpack that could slide off metal roofs (close call earlier this week in Island Park, ID).
Today, heightened avalanche conditions exist and the danger is MODERATE.
Please share avalanche, snowpack or weather observations via our website, email (email@example.com), phone (406-587-6984), or Instagram (#gnfacobs).
The possibility for a person to trigger an avalanche on older, deep buried weak layers is the primary concern. The likelihood of avalanches has decreased, but a person can trigger an avalanche with large consequences. Before traveling on or underneath steep slopes, evaluate the snowpack for buried weak layers and previous wind-loading and avoid heavily wind-loaded slopes, or slopes where you suspect buried weak layers exist.
See Doug’s video for a rundown on the aftermath of this week’s avalanche warning.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
Sunday, March 26, Avalanche Alliance Sweepstakes! Win a custom 2022 Ford 350 Super-Duty truck or many other items. Proceeds help support avalanche centers. Use code LASTCHANCE to receive 40% more tickets. Winners will be chosen at the Jackson Hole Hill Climb.
Loss in the Outdoors is a support group for those affected by grief and loss related to outdoor pursuits. Check out the link for more information.
Over the last week three people were killed in avalanches, and a total of 18 have been killed in avalanches in the U.S. this season. More info on each event is available at Avalanche.org Accidents Page.