fbpx Tumalo | Central Oregon Avalanche Center (COAC)


Recent avalanche activity
Intense precipitation
Observation Date/Time:
Sat, Feb 13, 2021 - 3:05 PM
Phil Bowker
Three Sisters Area / 7767'
Report Type:
Snow Conditions   Avalanche Activity  
Travel Mode:
Ski or Snowboard  
Sky Conditions:
Obscured (eg: fog)
Precip Type/Intensity:
Snow / S2 Moderate snow
New Snow:
20 cm
Height of Snow (HS):
195 cm
Wind Direction/Speed:
W / Strong: 26-38 mph

Written Report:
Toured up Tumalo today. With the 17cm (7") of new snow we received overnight ski penetration on the skin track up the west side was anywhere between 10 and 20cm.

On the summit winds where moderate to strong from the west. Visibility was poor with obscured skies (although the sun popped out for a brief moment). Air temp was -7c (19f) at 10am. Height of snow at the summit was 195cm and boot penetration was 44cm, indicating a lot of snow available for transport into the bowl, and there certainly was a lot of transport in that direction.

At the north end of the bowl I found a cornice extending about 1m out. Below the cornice in the bowl was some debris from a previous cornice collapse and recent avalanche. The cornice was stubborn to kick producing blocks around 1x2m. These blocks upon falling into the bowl did not trigger any slides.
In the bowl below the cornice I found an old crown about 30cm in height. Below the crown I found about 50cm of new storm snow and transported snow in a "right side up snowpack", fist over four finger hardness, well bonded to the old snow surface. As I skied beside the cornice debris I did not see any cracking or hear whumphing.
With the amount of snow being transported into the bowl I would expect to see new wind slabs forming in this area soon and should be approached with caution.

I found small, stubborn, isolated wind slabs, about 10cm in depth on the north east ridge skinning up out of the bowl. These wind slabs gave moderate hand shear results.



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