| Trigger | Skier | Remote Trigger | Unknown |
| Avalanche Type | Hard Slab | Aspect | North |
| Elevation | 2000ft | Slope Angle | 38deg |
| Crown Depth | 24in | Width | 20ft |
| Vertical Run | 50ft |
Avalanche: Turnagain
Location: Eddies
Eddies to 2300′. Checking out wind effect and the MLK Jr facet/buried surface hoar interface with the recent storm snow within the snowpack.
Pluming observed off of Pyramid and Carpathian on the drive to the Pass.
Avalanche Details
We found two skier triggered avalanches as we were skiing down that both looked to have been triggered the day before. One was a small wind slab that was only 4-6" deep. The other was a bit bigger and failed on buried surface hoar 1-2' deep on a steep convexity that was wind loaded.
We don't know if anyone was actually caught or carried.
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | No |
Observer Comments
Two skier triggered avalanches
Active wind transport starting around 3:00pm
Weather
Cloudy skies with light snow starting around noon.
Temperature was 3°F at start of tour and 20° at the end @ 500'. Seattle ridge wx station in the upper single digits during the tour.
Winds picked up around 3 pm and were northeasterly and gusty.
Snow surface
As soon as we popped out of the trees wind effect was noticeable to varying degrees. Generally a 1-6" wind crust, getting more pronounced the higher we went and the more exposed the terrain.
Snowpack
See photos.
The weak snow that formed in the cold clear weather in January got buried by a series of storm with the first one being on MLK Jr day. Since the layer was buried by that storm we are tracking it as the MLK Jr layer. This is now 2-3' deep. We found buried surface hoar at the top of the facets in both of our pit locations and the impromptu crown investigation we did on a recent skier triggered avalanche on at 1900' on N aspect of Eddies.
Wind effect @ 1300'
Wind crust @ 1300'
Hand pit to the facets and the NYE crust @ 1350'
Snowpack at 1850', 34° slope, NW aspect, HS:205 , MLK Jr buried surface hoar and facets 70 cm (2.3') down.
Laid over buried surface hoar and facets at the failure plane in a compression test. This was the layer of concern. CT 14 SC, CT 16 SC, ECTP 24, ECTP 26
Wind slab in the pit @ 1850'
Snowpack @ 2300', N aspect, 23° slope, HS: 254 cm, MLK Jr buried surface hoar and facets down 75 cm (2.5'), CT 15, CT 16 ECTP 27
MLK Jr buried surface hoar and facet layer visible in the pit wall
Skier triggered wind slab presumably from yesterday (2.1.20) on N aspect at 2150'. 4-6" crown
Second skier triggered avalanche also presumably from yesterday (2.1.20). The crown was 1-2' deep and the weak layer was the buried surface hoar/facet layer that was buried during the MLK Jr storm.
Looking down avalanche # 2
Crown depth
Buried surface hoar was the weak layer in ax #2
Facets just below the buried surface hoar, ax # 2
Slab over the bsh:facets @ 2300'