18-19
A snowbiker was partially buried in a slide on the west side of Sage Peak in the southern Madison Range. The slide occurred on a southwest facing slope at 8,700 ft. and failed on weak snow near the ground. The wet slab avalanche was triggered as the biker was side-hilling across the slope. He was caught, carried and buried to his chest, but fortunately escaped unharmed. Photo: D. Talbert
GNFAC Avalanche Forecast for Fri Mar 22, 2019
<p>Daytime warming and weak refreezes at night are taking a toll on the snowpack. Over the past few days, widespread avalanche activity has been observed across the forecast area and more action is likely today. Most activity has been confined to wet snow avalanches occurring on steep sun exposed slopes, but a recent dry slab avalanche on the north face of Mt Blackmore indicates all slopes are feeling the heat (<strong><a href="https://www.mtavalanche.com/images/19/natural-dry-slab-avalanche-mt-bla…;). Dry slab avalanches on high north facing slopes are not a widespread problem. Yesterday, my partner and I found soft-stable snow on upper elevation shady slopes in the southern Madison Range. </p>
<p>Today, point release avalanches will be easy to trigger or could run naturally as the day warms (<strong><a href="https://www.mtavalanche.com/images/19/point-release-beehive-basin">phot…;, <strong><a href="https://www.youtube.com/watch?v=W4q4NdCfmX8&list=PLXu5151nmAvRNl9ku…;). Wet slab avalanches are a less likely but a more dangerous problem. Wet slabs are unpredictable and can run with a tremendous amount of force. Yesterday, skiers north of Bridger Bowl observed large wet slab and wet loose avalanches on many slopes (<strong><a href="https://www.mtavalanche.com/images/19/texas-meadows-wet-slabs-1">photo<…;, <strong><a href="https://www.mtavalanche.com/images/19/wet-loose-debris-near-playground"…;). Be especially aware of both these problems in steep rocky terrain or on slopes where the snowpack is less than 3-4 feet deep (<u><strong><a href="https://www.youtube.com/watch?v=O_M2PnMldm0&list=PLXu5151nmAvRNl9ku…;). </p>
<p>The easiest way to manage the avalanche danger today is to start early and end early. The snowpack will be locked up this morning, but grow increasingly unstable as the day progresses. Fortunately, increasing clouds and wind this afternoon should help the snowpack from completely falling apart.</p>
<p>For today, the avalanche danger will start <strong>LOW</strong>, but rise to <strong>MODERATE</strong> by this afternoon. </p>
<p>If you get out and have any avalanche or snowpack observations to share, contact us via our <u><a href="https://www.mtavalanche.com/node/add/snow_observation">website</a></u>, email (<u><a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a></u>), phone (406-587-6984), or Instagram (#gnfacobs).</p>
Dry Slab, Loose Wet in Hyalite
A skier sent in photos of multiple loose wet avalanches near Mt. Blackmore yesterday. Photo: G. Antonioli
A skier sent in these photos of multiple loose wet avalanches near Mt. Blackmore yesterday. Photo: G. Antonioli
Recent dry slab avalanche that was triggered by a falling cornice and failed at the ground. Photo: G. Antonioli
Northern Gallatin, 2019-03-21
Wet avalanche activity in the Bridgers
Two wet slabs released on the ground on the south-facing chutes off of Texas Meadow. The debris pile from the smaller of the two slides was 6' deep, and the larger of the two slides cleared most of the snow out of the chute with it. Multiple additional loose wet slabs had also released off E-SE aspects over the past 24 hrs. Some of these were large enough to break small trees. Photo: A. Schauer