Northwest Mountains

Seek out soft, wind-protected powder for the safest riding in steep terrain.   Thursday's wicked winds from the north left smooth and dense slabs scattered across the terrain, most commonly at higher elevations.   They aren't easy to trigger, but they will break above you and take you for a rough ride if they do.  Consider terrain consequences if you are riding where recent winds have formed stiffer slabs.  

The avalanche danger continues its downtrend after the midweek storm and Thursday's northerly wind event.  We're straddling the Moderate/Low fence today, with avalanche problems up to D2 (Northwest Mtns) and D2.5 (Southeast Mtns) in size in drifted terrain becoming increasingly rare and stubborn.  Several valuable observations from public and forecast teams are highlighting that Thursday's wind slab forming event was more significant than we originally expected.  Although wind slabs are on a healing trend, yesterday's observations include unstable test results in wind drifts and front-row seats to a large natural wind slab avalanche, both failing on the mid-storm low-density layer that has been unusually productive this week. Furthermore, an observer spotted a fresh-looking natural avalanche off of Schuylkill Ridge that likely broke on the crusty/faceted storm interface.   Our travel advice today is to continue to evaluate snow and terrain carefully on wind-loaded features until our confidence with these issues improves. Easy enough, because the safest and highest quality riding conditions are out of the wind and on shady aspects where the snow is softest. Go find that steep soft powder and avoid the firmer and unfriendly drifts!  

In the Southeast Mountains, a wind slab on Thursday stepped down and triggered a much larger persistent slab avalanche (D2.5) on Carbonate Hill.   Thus the pattern continues; wind drifting events and humans venturing onto wind-drifted slopes shortly after continue to produce occasional persistent slabs in our shallower snowpack zone.  It's a low-likelihood problem that is difficult to assess because of the significant variability of weak layers and slabs in wind-affected terrain.  The slopes that are most worrisome for human triggers are recently drifted with variable slab thicknesses.  Forecasters yesterday below treeline in the Northwest Mountains and below treeline in Capitol Creek (on the Aspen side) found propagating test results on buried persistent weak layers.  Although it has been a long time since we've seen a persistent slab avalanche in our deep zone, or below treeline in either zone, those results are good reminders to guard against surprises by practicing mid-winter travel protocols, even where the danger is rated Low.  That means riding one at a time in steep terrain, carrying rescue gear, etc.  

If we see the high end of snow and wind forecasts tomorrow, a fresh round of small wind slabs will keep the danger elevated at Moderate in the alpine. Elsewhere, we expect the danger to remain or trend down to Low with current problems continuing to adjust and become more isolated.