fbpx Tumalo | Central Oregon Avalanche Center (COAC)
Rapid temperature rise
Observation Date/Time:
Thu, Apr 29, 2021 - 2:27 PM
Phil Bowker
Three Sisters Area / 7776'
Report Type:
Snow Conditions  
Travel Mode:
Ski or Snowboard  
Sky Conditions:
Few (1/8 - 2/8)
Precip Type/Intensity:
No Precipitation
Height of Snow (HS):
300 cm
Wind Direction/Speed:
SW / Light: 1-16 mph

Written Report:
Today on the top of Tumalo Butte at 11:37 the air temp was +10C (50F). Skies had a few scattered cirrus clouds, winds light from the southwest. The snow surface I encountered on all aspects of the butte was a mixture of old melt freeze forms covered by up to 5cm of decomposing snow from the recent storm cycle. On top of the butte I measured the height of snow to be greater than 300cm, Boot penetration was 10cm.

In Tumalo Bowl the snow was heavy and wet at this time, with a ski penetration of up to 10cm. Skiing produced cohesive roller balls, but not any Loose Wet slides. Digging into the snowpack I found an old crust about 10cm down. below this crust the snow was damp but still well bonded and strong. Above the crust the snow was wet with the top 5cm having free water.

The presence of wet unconsolidated slushy surface snow is perfect for producing Loose Wet avalanche problems. With future daytime temps around 10c(50f) this needs careful evaluation in consequential terrain.



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