| Trigger | Skier | Remote Trigger | Yes |
| Avalanche Type | Hard Slab | Aspect | Northwest |
| Elevation | 3800ft | Slope Angle | 38deg |
| Crown Depth | 18in | Width | 40ft |
| Vertical Run | 100ft |
Avalanche: Hatcher Pass
Location: Stairstep
Toured up Stairstep on a mission to find buried surface hoar, observe recent wind effect, and get some good turns in. Southerlies had a 3-4″ thick softened sun crust and northerlies had low density slow pow. We remotely triggered two small wind slabs at 3800′ on NW aspects.
Avalanche Details
As we got above 3500' it was obvious that the past 10 hrs of wind was enough to build significant wind slabs 6" to 18" thick near ridgeline on leeward aspects on the Arkose ridgeline (always sees more wind than IM bowl). We walked up the ridge and remotely triggered a small D1. We intentionally remotely triggered another similar size avalanche. Both failed on radiation recrystallization crystals within old snow. See pic
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | Yes |
Observer Comments
No cracking collapsing or recent avalanches below 3500'.
Recent small wind slabs at NW 3800'+ that we remotely triggered which also produced long shooting cracks up the ridgeline - see pic
Cooler daytime temps limited natural wet loose activity today.
Weather
1-2" new snow overnight at 3550'
Calm to light winds
Overcast/cloudy skies in the morning and sunny in the afternoon
2700' 34 deg at 12pm
3550' 29deg at 12pm
4500' 22deg at 12pm
Felt significantly cooler today than the past couple days.
Snow surface
Sun crust on southerlies below 3500'
NSF on northerlies with supportable base - boot pen 35 cm, ski pen 10 cm
Stiff wind slab on ridgelines above 3800' on W to N aspects
Snowpack
Our goal was to look at upper layer instabilities, ie find BSH. We did not dig more than a a couple feet deep.
HS 240cm @ 3000' NW
0-20 F DF
20-35 4F rounds
35-37 I crust (Feb 26)
ECTX
no buried surface hoar (BSH) observed at this elevation
HS 285cm @ 3500' W
2-3mm BSH found 45 cm down
BSH was non reactive in this location
ECTN
shooting cracks today
crown and flank of avalanche
shooting crack, track, and debris from avalanche
remotely triggered wind slab
3/16 Beginning of the formation of radiation recrystallization that wind slab failed on
Surface hoar- look in the middle. We have found this buried between 3500-4500' on NW to NE aspects