19-20
The red dashed lines mark the sides of the shallow avalanche that broke on surface hoar. It was triggered by a snowmobiler on 29 March in First Yellowmule (N aspect; 9500'). Photo: GNFAC
Avalanche Details: Snowmobile triggered on Buck Ridge
Forecast link: GNFAC Avalanche Forecast for Tue Mar 31, 2020
Northern Madison, 2020-03-30
Forecast link: GNFAC Avalanche Forecast for Tue Mar 31, 2020
We dug this pit adjacent to a snowmobiler triggered avalanche. It broke on the surface hoar layer which is located at the top blue crystal card. The bottom card denotes the larger grains of facets that formed early in the winter. Photo: GNFAC
Forecast link: GNFAC Avalanche Forecast for Tue Mar 31, 2020
This surface hoar crystal is almost 1.5 cm (each square is 2mm) and was the weak layer in a few avalanches on Buck Ridge (3/29/20). Photo: GNFAC
There were many tracks in Buck Ridge and only a few small slides in First Yellowmule. This picture is looking SW towards Sphinx Mountain. Feathery crystals of surface hoar are buried 1-1.5' under the surface and are a concern. This layer seems to be more prevalent in protected areas. Photo: GNFAC
We saw this natural avalanche from afar. It was NE aspect and likely failed on a layer of surface hoar 1-1.5' deep. The Madison Valley is in the background. Photo: GNFAC
Avalanche Details: Natural avalanche near Cedar Mtn.
Forecast link: GNFAC Avalanche Forecast for Tue Mar 31, 2020
Northern Madison, 2020-03-30
Forecast link: GNFAC Avalanche Forecast for Tue Mar 31, 2020
GNFAC Avalanche Forecast for Mon Mar 30, 2020
Snowpack and Avalanche Discussion
<p>Yesterday a snowmobiler triggered a slide on Buck Ridge when he descended to help another stuck rider, nobody was caught (<strong><a href="https://www.mtavalanche.com/node/22593">photo and details</a></strong>). The slide broke a foot deep on the crust below last week’s snow. Several slides broke on this layer last week (<a href="https://www.mtavalanche.com/images/20/skier-triggered-slide-hyalite"><s…;, </strong><a href="https://www.mtavalanche.com/images/20/two-natural-avalanches-beehive-ba…;, </strong><a href="https://www.mtavalanche.com/weather/wx-avalanche-log"><strong>weather and avalanche log</strong></a>). Over the weekend we received reports of consistent unstable test scores on this layer, including our own findings in Taylor Fork and Lionhead (<a href="https://www.youtube.com/watch?v=ZkyjbN1sWl0&list=PLXu5151nmAvSbcbVf…;). Today avalanches are possible to trigger, breaking above and sliding on the crust 1-2 feet deep. Dig down a couple feet to assess snow stability. Avoid steep slopes where you find a slab of snow sitting on top of a crust.</p>
<p>Yesterday’s sun and warm temperatures caused small wet loose avalanches and cornice fall triggered avalanches. We got reports of these in the northern Bridger Range (<strong><a href="https://www.mtavalanche.com/images/20/natural-cornice-fall-fairy-lake">…;) and Hyalite (<strong><a href="https://www.mtavalanche.com/images/20/natural-cornice-triggered-avalanc…;). Today warm temperatures and some sun make wet avalanches and cornice falls possible. Avoid steep slopes where the snow surface gets moist or wet, and be cautious of steep, rocky terrain above you where natural wet avalanches might initiate (<strong><a href="https://www.mtavalanche.com/images/20/point-release-avalanches-east-fac…;). Cornices can break further back than expected, and possibly trigger large avalanches. Stay far back from cornices along ridgelines and avoid slopes directly below (<a href="https://www.mtavalanche.com/images/20/huge-cornices-lionhead-ridge"><st…;).</p>
<p>Areas that received a few inches of snow last night are forecast to be cloudier with more snow this afternoon. I expect minimal wet snow there, but even brief clear skies will make wet slides possible. Increasing wind and possibly more snow this afternoon will form fresh drifts. Avoid these slabs which may be large enough to bury a person or can push you into hazards like trees, rocks or over cliffs.</p>
<p>Today heightened avalanche conditions exist and avalanches are possible. Carefully evaluate the snowpack and make conservative choices. Avalanche danger is rated MODERATE.</p>
<p>We plan to end daily avalanche forecasts on Sunday, April 5<sup>th</sup> and continue with general bulletins every Monday and Friday through April. We have taken down most weather stations and will no longer receive observations from guides and ski patrol. We need help gathering field data. Please send us your observations no matter how brief. You can fill out an <a href="https://mtavalanche.us17.list-manage.com/track/click?u=6653a830e4819c9e…; target="_blank">observation form</a>, email us (<a href="mailto:mtavalanche@gmail.com" target="_blank">mtavalanche@gmail.com</a>), leave a VM at 406-587-6984, or Instagram (#gnfacobs).</p>
Backcountry Skiing and Stay-at-home Directive
Please consider mellower terrain and lowering your risk to reduce potential for a needed rescue. Also, consider that the distraction of current events may cloud our judgment which compromises our ability to safely attempt more challenging objectives. Take a step back. Ride Safe.
From obs (3/29/20): "...in Maid of the Mist basin there were multiple loose wet avalanches [and a slab] caused by a piece of the cornice falling off on Pt. 10201." Photo: N. Salsburg
Avalanche Details: Natural cornice triggered in Maid of the Mist basin
Northern Gallatin, 2020-03-30
From obs (3/29/20): "On our approach to Maid of the Mist, my partner and I watched several small point release avalanches on the east face of Palace Butte..." Photo: N. Salsburg
Forecast link: GNFAC Avalanche Forecast for Mon Mar 30, 2020