21-22

<p>Today, there is not much wind and not much new snow. You may find isolated wind slabs near the ridgelines that could be triggered, but these would be few and far between. Yesterday skiers backed out of avalanche terrain in Hyalite and south of Cooke City when they got wind drifts to crack. Today these drifts will be less likely to fracture.&nbsp;</p>

<p>A couple days ago a thin and wide avalanche broke free on Saddle Peak. Alex took a <a href="http://www.mtavalanche.com/images/22/shallow-wide-avalanche-saddle"><st…; yesterday and its width caught our attention. Slides that propagate far typically have a weak layer underlying the slab and we are hypothesizing that a razor-thin layer of facets might have been responsible. We will check it out today. The odds of getting caught in a slide like this can be lessened with a quick stability test of the new/old snow interface. <em>Throughout the forecast area our avalanche concerns are limited to the upper foot of the snowpack.</em> In the Bridger, northern Gallatin and northern Madison Ranges this interface is where instability will show itself. In the southern Madison and southern Gallatin Ranges, Lionhead and Cooke City, in addition to this interface there’s a weak layer of surface hoar buried about 8” deep. We mitigate both concerns the same way, by digging and testing instead of blindly throwing ourselves into avalanche terrain.&nbsp;</p>

<p>Avalanches are unlikely throughout our forecast area today and the danger is rated LOW on all slopes. As always, retreat if you find instability (cracking, poor test scores), and when you find good slopes to slide and ride on only expose one person at a time.&nbsp;</p>

<p>If you get out, please send us your observations no matter how brief. You can submit them via our <a href="https://www.mtavalanche.com/node/add/snow_observation"><strong><u>websi…;, email (<a href="mailto:mtavalanche@gmail.com"><strong><u>mtavalanche@gmail.com</u></str…;), phone (406-587-6984), or Instagram (#gnfacobs).</p>

<p>The arithmetic is basic: Wind + snow = wind slabs. 4-6” of snow that fell in Hyalite and Big Sky Monday night got blown into thicker drifts that can be triggered today. On slopes not affected by the wind it’s unlikely to trigger an avalanche. Ian and I were on <a href="https://www.mtavalanche.com/node/19525"><strong><u>Wheeler Mountain</u></strong></a> in the northern Gallatin Range yesterday and found sugary, faceted snow that would not support our weight when we stepped out of our skis (<a href="https://youtu.be/6ax6l1PhUb0"><strong><u>video</u></strong></a&gt;). We also found 6” of new snow that was likely blown into drifts last night. A skier on Divide Peak and the Big Sky Ski Patrol also reported fresh snow available for transport.&nbsp;</p>

<p>Wind drifts are most susceptible to triggering when they are new, like today. Shooting cracks are a sign that slabs of windblown snow can avalanche. Be wary near ridgetops. On slopes without wind loading it’s a good habit to dig and test before getting on steep terrain no matter the danger rating. For today the avalanche danger is rated MODERATE on wind loaded slopes and LOW on all others.</p>

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<p>The Bridger Range is windy, but lacks new snow to blow around. The southern mountains to West Yellowstone and Cooke City are calmer. Without new snow to load slopes or get blown into drifts the snowpack is generally stable and avalanches are unlikely. A buried weak layer of surface hoar is still lurking a foot or so under the surface in our southern mountains, but is not a serious concern…yet. It needs to get buried deeper, which may take a while given our paltry storms. Alex shows us this layer and reminds us to look&nbsp; for signs of instability like shooting cracks in his <a href="https://youtu.be/I6AleixLxTI"><strong><u>video from Taylor Fork</u></strong></a> this weekend. To avoid getting unlucky and finding a rogue instability, do a quick stability test before exposing yourself to serious terrain. For today the avalanche danger is rated LOW.&nbsp;</p>

<p>If you get out, please send us your observations no matter how brief. You can submit them via our <a href="https://www.mtavalanche.com/node/add/snow_observation"><strong><u>websi…;, email (<a href="mailto:mtavalanche@gmail.com"><strong><u>mtavalanche@gmail.com</u></str…;), phone (406-587-6984), or Instagram (#gnfacobs).</p>