23-24

<p>Variations in this week’s weather will drive a wide range of avalanche conditions. Monday and Tuesday will be the warmest days, with a mix of rain, snow, and sun and a continuation of wet snow avalanche activity. Snow and cooler temperatures move into the area on Tuesday night, increasing the risk of dry snow avalanches. As Alex described from the Bridger Range on Sunday, conditions evolve quickly in the spring, and our decision-making needs to evolve with these changes (<a href="https://www.youtube.com/watch?v=TJm0MFOeqCA"><strong><span>video</span>…;

<p>On Monday, mountain temperatures remained above freezing for four days at all but the highest elevations. All bets are off as rain adds water to the snowpack. Wet loose snow and wet slab avalanches are likely. Yesterday, a group of riders remotely triggered a wet slab avalanche near the Taylor Fork (<a href="https://www.mtavalanche.com/node/31856"><strong><span>photos and details</span></strong></a>), and wet slab avalanches failed naturally above Quake Lake (<a href="https://www.mtavalanche.com/node/31850"><strong><span>photo and details</span></strong></a>) and in the Southern Gallatin Range in Yellowstone National Park (<a href="https://www.mtavalanche.com/node/31852"><strong><span>photo and details</span></strong></a>). These are destructive additions to the widespread wet, loose snow avalanches that initiate at a point and fan out as they entrain snow (<a href="https://www.mtavalanche.com/node/31834"><strong><span>photos from Bridgers</span></strong></a>). The snow is unstable on a spectrum, from when the upper few inches of the snowpack are wet and slushy to the entire snowpack being unsupportable. Avoid steep slopes and runout zones where these scenarios are present.</p>

<p>Avalanches within the new and wind-drifted snow will become the primary concern mid-week as cooler temperatures and snowfall return to the area. The size and likelihood of storm snow avalanches will be directly related to the amount of new snow and wind we receive. Watch for signs of instability, such as shooting cracks, and dig down to ensure you have a supportable crust below the new snow, testing for instability to this level. Avoid steep slopes where you find instability.</p>

<p>Finally, give the large cornices along ridgelines a wide berth when on ridgetops, and be cautious when traveling on slopes below them, as a collapse can trigger an avalanche below (<a href="https://www.mtavalanche.com/images/24/cornice-collapse-sphinx"><strong>… photo</span></strong></a>, <a href="https://www.mtavalanche.com/images/24/iceberg-peak-cornice-fall"><stron… Peak photo</span></strong></a>). Consider older persistent weak layers and wind slabs on upper elevation slopes that remained shady and cool during the warm-up.</p>

<p><span>Daily forecasts are done for the season, but avalanches will continue. Remain diligent with your snowpack assessments and route-finding, and adapt your decision-making to changing conditions.<span>&nbsp; </span></span></p>