Hazard is at low for all elevations of Douglas Island. Low density, dry, unconsolidated snow sits on top of the freezing rain crust from 3/6. This snow has been sloughing on steeps but shows no slab properties. The exception is small, isolated pockets of wind slab on southerly aspects near ridgetops that have shown some reactivity. Be mindful of heavy sloughing in steep terrain and watch for signs of instability such as dense, smooth, pillows, hollow or drum-like sounds, and shooting cracks near ridgetops and on south faces.
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A northerly outflow wind event began on 3/11 with moderate winds predominantly from the northeast. Winds have since decreased to mostly light with occasional moderate gusts. Wind slabs likely formed during the peak winds on 3/11 and should be decreasing in reactivity.
Low-density snow early in the week, paired with the northerly outflow wind event on 3/11, created potential for wind slab formation. Winds were predominantly out of the northeast and ranged from moderate to light. With ~30 cm (~1 ft) of low-density snow available, there was plenty of snow available for transport.
Wind slabs will be specific to south aspects, with slabs measuring roughly 20–30 cm thick. We expect the overall hazard from these slabs to be decreasing, as they were likely formed during the strongest winds on 3/11 and winds have been relatively light since. However, continue to watch for signs of instability such as dense, smooth pillows, hollow or drum-like sounds underfoot, and/or shooting cracks.
We dug a pit on a southerly aspect behind High East on 3/13. The primary objectives were to assess the current snowpack ahead of the incoming storm and evaluate the reactivity of recently transported snow from the 3/11 northerly outflow event. We also were looking for evidence of persistent grains around the 2/28 freezing rain crust and the 3/6 melt-freeze crust, and conducted a Propagation Saw Test (PST) below the 3/6 layer to evaluate propagation potential.
As we were skinning up, we observed a scoured ridgeline with patches of rime. Once we moved onto the leeward side, we began to observe shooting cracks. We measured 20–30 cm of 1F wind slab at the surface, composed primarily of wind-packed rounds. This layer was reactive, producing an ECTP20 with a fracture 26 cm down.
We identified the 3/6 melt-freeze crust (4 cm thick) at 39 cm down. A PST conducted below this crust resulted in PST 100/100 (End), suggesting this layer is currently well bonded within the snowpack.
The 2/28 freezing rain crust was located 86 cm down. We did not observe test results on this layer; however, while shearing off the ECT column, the column sheared just below the freezing rain crust at approximately 86 cm down.
We spent considerable time examining crystal forms and primarily observed various stages of decomposing fragments. We did not find evidence of persistent grains in this pit. A 1 cm sun crust had begun forming on the surface by the time we left the site around 1330.
An active weather pattern is approaching. Snow is expected to begin late this afternoon, with the storm intensifying on Sunday and bringing moderate to heavy snowfall throughout the region.
