20-21

<p>Wet avalanches are our main concern today. Yesterday's temperatures reached the 40s and sunny slopes moistened but held together. There were no widespread loose avalanches. On slopes that were shady the snowpack is still cold and wintry. Today will be a few degrees warmer, yet a breeze might provide enough cooling to keep avalanche activity in check. It will take a couple hours for the frozen surface to soften up and in general I expect small, wet loose avalanches on sunny slopes. The interplay of elevation, aspect and timing is critical because the snow surface and avalanche danger can change rapidly. Ian explains it further in his <a href="https://youtu.be/g8s9PZB134E"><strong><u>video</u></strong></a&gt; from Lionhead.&nbsp;</p>

<p>You don’t need a compass or watch to inform you where and when slopes become unstable, just pay attention. Sunny slopes will get wet and gloppy. The more intense the sun is, the wetter slopes will become. A sign that wet avalanche danger is rising is sinking past your ankles in wet snow or seeing large pinwheels of snow rolling downhill.&nbsp;</p>

<p>Dave was in Taylor Fork and Lightning Creek yesterday and had 3 things on his mind: wet avalanches, a potential new weak layer at the surface if it gets buried (near-surface facets), and also sugary depth hoar near the ground which broke in his test (<a href="https://youtu.be/3Adq_x3APAg"><strong><u>video</u></strong></a&gt;). The wet snow is the primary concern today, but the other two may become problems when it snows Friday night.&nbsp;</p>

<p>For today, the <strong>wet snow avalanche danger</strong> will start out LOW but rise to MODERATE on slopes that become wet and slushy.&nbsp;</p>

<p>The <strong>dry snow avalanche danger</strong> is rated LOW on all slopes because avalanches are unlikely.</p>

<p>The mountains outside Cooke City reached the low 40s yesterday. Today will be a few degrees warmer and sunny slopes will get moist and shed surface snow in wet loose avalanches. Wind is expected to keep the snow surface cool which will inhibit avalanches becoming widespread. On slopes not affected by the sun the snowpack is dry and mostly stable (<a href="https://youtu.be/VQd7lPN6zTQ"><strong><u>video of current conditions</u></strong></a> from Tuesday).</p>

<p>For today, the <strong>wet snow avalanche danger</strong> will start out LOW but rise to MODERATE on slopes that become wet.&nbsp;</p>

<p>The <strong>dry snow avalanche danger</strong> is rated LOW on all slopes because the snowpack lacks buried weak layers and avalanches are unlikely.&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><strong>WET AVALANCHE DANGER</strong></p>

<p>The sun’s power is intense. Low elevation slopes that get sunshine are melting, getting slushy and becoming quickly unstable. Today's clear skies and unseasonably warm temperatures will also impact high elevation slopes that are sunny. If you are sinking past your ankles in wet snow you are susceptible to triggering or getting caught in a wet avalanche (loose slides at high elevations and wet slabs at lower) and heading out of the backcountry is recommended. You can seek shady, cooler aspects (ie. high, northern facing slopes), but unless you parked your vehicle there, you'll have to navigate wet terrain on your exit. Ian was in Lionhead yesterday and saw first-hand how aspect, elevation and timing affects wet avalanche danger (<a href="https://youtu.be/g8s9PZB134E"><strong><u>video</u></strong></a&gt;). Today I expect many loose wet avalanches as well as cornices sagging and potentially breaking (<a href="https://www.mtavalanche.com/images/21/cornices-along-lionhead-ridge"><s… from Lionhead</u></strong></a>, <a href="https://www.mtavalanche.com/node/24618"><strong><u>Abiathar cornice fall</u></strong></a>). The <strong>wet snow </strong>avalanche danger will start LOW but rise to CONSIDERABLE on all sunny slopes.&nbsp;</p>

<p>On slopes that remain dry the snowpack will be generally stable. There is still weak snow (depth hoar) near the ground and a person would have to be extremely unlucky to trigger an avalanche on this layer. For today the <strong>dry snow</strong> avalanche danger is rated LOW on all slopes.</p>

<p>Yesterday I toured up Sheep Creek north of Cooke City and found a frozen surface on one side of the valley (SW facing) and dry snow on the opposite (NE). I dug on a northeast aspect at 9,000 feet and did not find any weakness, nor did I see any signs of instability (<strong>video</strong>). There might be a rogue wind slab lurking about, but in general it is unlikely someone could trigger an avalanche. These mountains will reach the low 40s F this afternoon and triggering wet avalanches is a possibility, mostly on sunny, lower elevation slopes. For today, the dry snow avalanche danger is rated LOW. The wet snow avalanche danger will start LOW but rise to MODERATE on slopes getting sun. Seeing roller balls, pinwheels or sinking past your ankles in wet snow are signs to head home.</p>