| Trigger | Natural | Avalanche Type | Soft Slab |
| Aspect | North | Elevation | 2400ft |
| Slope Angle | 27deg | Crown Depth | 4ft |
| Width | 125ft | Vertical Run | 250ft |
Avalanche: Douglas Island
Location: Twin C.
Observed widespread deep natural avalanche crowns throughout the watershed. Dug into the snow just below a crown line to test the reloaded snowpack on the bed surface that had slid. Then dug into the snow above the crown line to test the bed surface/weak layer that had avalanched. Got significant propagation saw tests both below and above the crown, on two different layers. Persistent weak layers remain present both in snow packs that have already released, and those that haven’t yet.
Avalanche Details
Many natural avalanche crowns, looked to be about the same depth, on all aspects N-E-S. Likely released in the last week of February. Next watershed over did not have any visible deep crowns yet. Perhaps they are waiting for more load...
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | No |
Observer Comments
Pretty much everything on steeper slopes near the top of the ridge we were on had slid deep. Also observed cracks that had been covered by recent snow but were still identifiable.
Weather
Overcast, cool, light S breeze. Intermittent and very light snowflakes just starting to fall before the storm front.
Snow surface
3-5mm surface hoar.
Snowpack
See snow profiles. Persistent weak layers are still out there! The slabs are just getting deeper. Consequences are increasing as the predictability of triggering decreases.
Profile below the crown line
Profile above the crown line
The crown line that we dug into
The excavated interface between the reloaded bed surface and the overhanging crown
Investigating the rounding facets on the planar shear below the Jan 18 melt freeze crust
The rounding facets on the planar shear above the Feb 4 freezing rain crust
Widespread deep propagations (aka no escape) into terrain traps