Thank you to the group for sharing this observation. Looking at the distance from which this was remotely triggered, and considering other observations of poor structure in the area, there is a good chance this failed on a weak layer of buried facets. We have gotten quite a few concerning observations recently, and it would not be surprising to see more similar activity.
Avalanche: Chugach State Park
Location: Bowls to the West of Harp
Skinned up the valley to the bowl west of harp. Noted pretty wind affected slopes, particularly South/SE/E.
Forecaster Comments
| Trigger | Snowboarder | Remote Trigger | No |
| Avalanche Type | Hard Slab | Aspect | West |
| Elevation | 4000ft | Slope Angle | unknown |
| Crown Depth | unknown | Width | unknown |
| Vertical Run | 500ft |
Avalanche Details
Hard slab, broke above me while I was about 150 yards past it. Likely D1.5. Ran about 500 feet and did not appear to pull out any other layers. We did not investigate the crown, but the debris was quite soft and likely was new snow which had been wind transported, which formed a harder slab and likely failed on old surface crust.
Events of the day
We were aware of the new snow and high winds from the previous and thus went into the day with a cautious mindset. We skied one run without incident. On the second lap, another party member and I, skied further left. I noted increased wind effect on the snow as he skied down. I rode this slope second and felt stiffer snow for the first two turns, which then resolved as I descended. The others in my group noted a slab pulled out approximately 150 yards behind me, however I was unaware of this until I had reached the group. It was initially quite slow moving, but did eventually pick up some momentum. It did not appear to pull out any deeper layers. It was probably D1.5. I was unaware of triggering this until I had reached the group at the bottom of the run. Fortunately we utilized good travel protocol and skied one at a time and met in a safe zone. We did note increasing winds as the day progressed.
Rescue events
N/A
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | No |
Observer Comments
We observed slides on similar aspects which appeared to have failed mid storm, as they were partially buried and obscured. We did see another hard slab that appeared to have occurred recently and naturally back in the hanging valley. (Forecaster Note: this avalanche seen in the Hanging Valley could have been one of the two that were remotely triggered by another group the day before. Their report can be found on the observation page for March 19.)
Weather
Clear, sunny, seasonably warm in the sun. Winds 5-10 with gusts to 15mph. Winds increased throughout the day
Snow surface
Significant wind effect noted on most aspects, but most pronounced on S/SE/E aspects. Protected gullies and bowls had soft snow
Snowpack
No formal stability tests. Suncrusts noted on solar aspects. High spatial variability with relatively poor structure as is typical for the area.
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