Northwest Mountains

In the week of dry weather following our big storm and avalanche cycle, the snowpack has evolved to a low likelihood, serious consequence setup.  We recommend a more cautious approach as you gain elevation into wind affected terrain, where slabs and weak layers are more variable.  You can lower your risk by riding at lower elevations, on slopes with a consistently deep and uniform snowpack, and on paths that ran naturally during the storm.   The low angle is riding fast and fun right now as well!  

Now a week since the major atmospheric river event ended, we continue to see gradual improvements to the snowpack.  The main processes driving these changes are weak layers rounding and bonding under the slabs, and slabs starting to decay as the upper snowpack facets.   In the Northwest Mountains, we've lowered the likelihood to "Unlikely."  The average slope either avalanched during the storm or is reaching equilibrium under its current load, but we anticipate isolated outliers.  We recommend more cautious travel at higher elevations because that's where lingering instabilities will be largest, and because wind-affected slopes are more variable, so we have greater uncertainty.  For example, you might find a windward slope that was eroded into a very shallow and unusually weak snowpack during November and subsequently formed a wind-stiffened slab of variable thickness during the big storm: good ingredients for a slower-to-heal setup.   These avalanches in Wolverine Basin are examples of that situation.  

The same improvements are occurring in the shallower Southeast Mountains, though the decrease in likelihood is expected to be slightly slower near and above treeline. We suspect a few more slopes fit the description of unusually shallow and weak before the storm, now drifted over by a stiffer slab.  Our data from the eastern side of our forecast area is still limited this time of year. However, outside of our forecast area, regions with a shallower snowpack have shown evidence of slower-to-improve stability and a less extensive flush from the big storm.   

As the upper snowpack continues to facet and lose strength, stay alert for small loose dry avalanches on sustained, steep terrain.  The snow on top of old bed surfaces is losing strength rather quickly, as shown in this video from Mt. Axtell earlier this week. 

Events: Avalanche Awareness Night is at the Center for the Arts this Saturday. Doors open at 6, show starts at 7. We will have presentations for the first half and live music for the second half of the night. The Beacon Brush Up is then behind the Crested Butte Community School on Sunday from 9 a.m.- 2 p.m.  Details are here.