Avalanche: Hatcher Pass

Location: Independence Mine Bowl

Date:
Observer:
Route & General Observations

Observations from the Independence Mine Bowl and Hatcher Pass / April Bowl area. Snowmachined up to Hatcher Pass hoping to snowmachine down into Upper Willow Creek to check out conditions. A crown from the weekend on the W side of Hatcher Pass had completely filled back in with snow and was actively loading. Wind drifts were covering signs previously exposed by several feet and fresh looking debris could be seen off the W side of Bennett’s Ridge funneling near the snowmachine trail. We decided to not snowmachine down based on concern the W side of the pass was loaded up and ready to release a wind slab avalanche. We instead skinned up Bennett’s Ridge through strong winds to 4300′ and turned around and headed back down the way we had come up.

Avalanche Details
If this is an avalanche observation, click yes below and fill in the form as best as you can. If people were involved, please provide details.
Trigger NaturalAvalanche Type Hard Slab
Aspect East NortheastElevation 3900ft
Slope AngleunknownCrown Depth 24in
Width 100ftVertical Run 400ft
Avalanche Details

Natural wind slab avalanches observed in cross loaded gullies of Martin Ridge. Occurred some time between 3 pm and 5 pm. Largest avalanche was D2, and appeared to step down to deeper weak layers. Photos below.

Red Flags
Red flags are simple visual clues that are a sign of potential avalanche danger. Please record any sign of red flags below.
Obvious signs of instability
Recent Avalanches?Yes
Collapsing (Whumphing)?Yes
Cracking (Shooting cracks)?No
Observer Comments

Natural D1.5 wind slab avalanche on the west side of Hatcher Pass, NW aspect, 4000' (ran over the summer road to Summit Lake), occurred some time last night. Heavy wind transport since about 10 am, constant pluming along ridgelines, and occasional obscured visibility at valley bottoms.

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.
Weather

No precip overnight. Winds built overnight, increasing to SE 31 gusting 49 mph at 5 pm. Winds in Hatcher Pass near April Bowl felt "hurricane force", making it difficult to stand, hold on to ski poles, etc.

Snow surface

Surfaces range from scoured to basal ice, bare ground, wind crust, wind slab, high amplitude sastrugi, etc.

Snowpack

No stability tests performed.

Photos & Video
Please upload photos below. Maximum of 5 megabytes per image. Click here for help on resizing images. If you are having trouble uploading please email images separately to staff.