Harp

We found about 1 inch of new, low-density snow on the ground this morning, but along the ridge most surfaces were wind-scoured or compacted into firm windboard. In mid-morning, we felt the sun’s ever-so-subtle warmth; it was a Front Range beach day, and there was no better way to spend it than digging into the snow to see what lurked beneath our skis.

We dug a pit near the ridge at 3,900 ft and observed a structure similar to other recent observations in Chugach State Park. The upper foot of the snowpack consisted of wind-packed snow sitting atop a thin melt-freeze crust. In the mid-pack, we found well-developed facets formed during the cold, clear December, and at the ground we observed depth hoar. While we did not observe instability in these mid-pack facets or the depth hoar, extended column tests produced propagating failures in the upper foot of the snowpack on the hard wind slab above the melt-freeze crust (ECTP 25 × 2). These results align with expectations, as strong winds affected much of Chugach State Park late yesterday. By late afternoon today, conditions changed as mostly sunny skies gave way to strong northwesterly winds and an unexpected return of moderate snowfall. Above treeline, visibility deteriorated into blizzard conditions, and fresh, reactive wind slabs developed rapidly. We anticipate that wind slabs will remain touchy as winds continue to batter the region.

Fresh wind slabs were forming by late afternoon. We observed shooting cracks in small pockets of wind-blown snow near the ridge. While cracking remained shallow, strong winds and continued snowfall could quickly build larger, more reactive wind slabs.