Northwest Mountains

Dangerous avalanche conditions linger after an intense stormy period on Friday and Saturday.  Numerous natural avalanches occurred during periods of high snowfall and/or wind-loading.  Instabilities in the storm snow often take a few days to improve.  Recently drifted terrain offers the greatest risk as avalanche size would easily be large enough to bury you.   Use conservative terrain selection and make careful snowpack observations to manage the risk of avalanches in the recent storm snow.

Northwest Mountains:  In the deep snowpack Northwest Mountains, the primary concern lies with the recent snow.  Instabilities at the base and in the middle of the storm snow have been noted by observers and confirmed by natural avalanche activity on Saturday; Irwin Guides cat-ski tenure produced avalanche results through explosive control work.  The storm snow clearly accumulated in an "upside down" manner with denser snow accumulating above lower-density snow.  Storm snow weak layers often improve in just a few days but could continue to produce large avalanches today.  Leeward terrain remains the most suspect, due to southwest-to-west winds depositing very dense slabs that could be close to 4 feet thick on well-drifted slopes.  Carefully evaluate the snowpack and select conservative terrain to help reduce your risk of triggering a dangerous avalanche.  If you are in doubt about your chances of triggering an avalanche then reduce slope angles to less than 30 degrees and surf low-angled powder.

Southeast Mountains:  Observations from yesterday suggest that a Persistent Slab problem exists in the Southeast Mountains in addition to Storm Slabs.  Check out this observation from the Brush Creek area with natural avalanche activity involving weak layers deeper in the snowpack.  Additionally, a natural avalanche impacted Cement Creek Road (past the winter trailhead on the XC track) that may have involved Persistent Weak Layers.  Storm totals were very similar between the Northwest Mountains and the Southeast Mountains over the past 48 hours, but there is a clear increase in hazard in the Southeast Mountains due to the potential for avalanches to "step-down" into deeper weak layers.  Consider the possibility of triggering an avalanche remotely and it breaking wider and deeper than you expect.  Conservative terrain selection, like slope angles 30 degrees or less, without significant overhead hazard, is paramount for areas near and to the east of Crested Butte.  The risk of natural avalanche activity has decreased, but the threat of large human-triggered avalanches will likely linger longer in the Southeast Mountains.  Slopes that face south or southwest have a reduced threat of Persistent Slab avalanches.