Wind Slabs at Virginia Lakes

Location Name: 
Virginia Lakes
Region: 
Other Area
Date and time of avalanche (best estimate if unknown): 
Sat, 12/26/2020 - 14:00
Location Map: 


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

Observation made by: Avalanche Specialist
Avalanche Observations
Avalanche Type: 
Dry
Trigger type: 
Skier
Crown Height: 
1 ft
Aspect: 
Northeast
Weak Layer: 
Storm Snow
Avalanche Width: 
100ft.
Terrain: 
Near Treeline
Elevation: 
10 400ft.
Bed Surface: 
Storm Snow
Avalanche Length: 
30ft.
Number of similar avalanches: 
2
Number of people caught: 
0
Number of partial burials: 
0
Number of full burials: 
0
Did the avalanche hit a building, vehicle, or structure?: 
No
More detailed information about the avalanche: 

I went for an afternoon tour up by Virginia Lakes today and found 3-4 Inches of new snow accumulated from last night and this morning. The new snow has been heavily wind affected except on the most protected slopes.

Conditions are still pretty grim with a very thin snowpack in most places. Unfortunately the only places with enough snow to effectively ride are also the most concerning loaded slopes with wind and persistent slabs. Wind slabs on specific loaded terrain features were reactive to ski cuts today. I intentionally skier triggered a couple of SS-ASc-R1-D1-S, 6-18" deep, on some small wind loaded rolls. 

I also dug a pit on a more protected NE slope near tree line to take a look at the persistent slab problem. I found well developed facets and depth hoar at the gound and a decent slab on top from the recent storms. ECTP15 on the depth hoar. Pit profile attached. I did not note any other signs of instability on the depth hoar today. 

The greatest hazard out there right now is probably still hitting rocks and other buried objects, or triggering a small slide that takes you for a ride in rocky unforgiving terrain. 

 

Avalanche Photos: 
Snowpit or crown profile photo or graph: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
50% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Snow
Air temperature trend: 
Static
Wind Direction: 
West
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Moderate snow and moderate to strong winds out of the west at noon gave way to scattered clouds and somewhat lighter winds in the afternoon. Ridge top winds seemed to be strong enough to cause more sublimation than loading.