Strong Winds Transporting Snow

Location Name: 
Strong Winds Transporting Snow
Region: 
Long Canyon Area
Date and time of observation: 
Thu, 03/19/2020 - 11:25


Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Obvious avalanche path

Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

We picked up 3 to 5 inches of snow overnight, with lower amounts below 9500'.  Not sure why the road to Williams Lake TH was shut down so went up Long Canyon to see what the winds and storm snow was doing.  Had brief periods of intense snow (mostly graupel) at times, otherwise we only picked up an additional inch of snow through early afternoon.  Winds were incredibly strong knocking me off my feet many times and easily transporting snow from the windward side to the leeward side.  (See Video) Much of this snow was transporting further down slope than just below ridgelines.  By mid-morning we were easily triggering soft slab avalanches in the new wind drifted snow.  This was on East aspects that have had the most loading as well as cross-loaded gullies.  Visibility wasn't the greatest to get eyes on all terrain.  Much of the new snow was graupel and we were finding it pooling below cliffs and on gentler slopes.  The recent storm snow was falling on crusts from the high pressure previously and near surface facets on northerly aspects.

Photo 1: Small soft slab avalanche I triggered on a NE aspect near treeline

Photo 2: Graupel that was pooling on gentler slopes

Photo 3: About 6 inches of new snow that fell on a crust (East Aspect)

Photo 4: West winds easily transporting snow

Photo 5: Shooting cracks in the new snow 

Snowpack photos: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Strong
Precipitation: 
Snow
Air temperature trend: 
Static
Wind Direction: 
West
Accumulation rate: 
Less than 1 in. per hour