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Avalanche on Tumalo Bowl

Location Name
Tumalo Mountain
Region
Three Sisters Area
Name
Jeff Myers
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Position
Public
Date and time of avalanche (best estimate if unknown)
Red Flags
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Obvious avalanche path
Avalanche Type
Dry
Slab
Blowing Snow
Yes
Trigger type
Skier
Wind Speed
Light
Slope
34degrees
Wind Direction
Northeast
Air temperature
Below Freezing
Aspect
Northeast
Air temperature trend
Warming
Elevation
7775ft.
Bed Surface
Storm Snow
Cloud Cover
75% of the sky covered by clouds
Precipitation
Snow
Weak Layer
Other - please provide details in the comment field below
Crown Height
1 ft
Accumulation rate
<1
Avalanche Width
130ft.
Avalanche Length
300ft.
Terrain
Above Treeline
More detailed information about the weather

Light to moderate winds @ approximately 15-20mph, snow fall was very intermittent

More detailed information about the avalanche

Intentionally skier triggered on a convex area between the rock and cornice on the left side of Tumalo bowl.

First attempt (two ski stomps) to trigger the slide sent a shooting crack approximately 30ft into the bowl, Second attempt (two ski stomps)had the entire slope fail.

Weak layer was approximately 10-14in. down and was roughly 1/3in. deep, crystals looked like buried surface hoar. Test Pit showed two failures of CT 1 Q2 @ 10in.

A second weak layer was also present at approximately 20-24in., also a wind slab but with much less energy

Wind slab seemed to be formed from overnight snow blowing in