Post storm avalanches

Location Name: 
Avalanches near Sardine Meadows - Hwy 108
Region: 
BWRA
Date and time of avalanche (best estimate if unknown): 
Fri, 02/10/2017 - 00:00
Location Map: 


Red Flags: 
Recent avalanche activity
Recent loading by new snow, wind, or rain

Observation made by: Avalanche Specialist
Avalanche Observations
Avalanche Type: 
Dry
Slab
Trigger type: 
Natural
Crown Height: 
4 ft
Aspect: 
Northeast
Weak Layer: 
Storm Snow
Terrain: 
Near Treeline
Elevation: 
9 200ft.
Bed Surface: 
Old Snow
Number of similar avalanches: 
3
Did the avalanche hit a building, vehicle, or structure?: 
No
More detailed information about the avalanche: 

We observed numerous wind and storm slab avalanches in the BWRA today, likely failing sometime Thursday night or Friday.  The two avalanches shown below were seen from Hwy 108 near Sardine Meadows, located SW of the road.  The first photo shows a large crownline from what appears to be a cornice collapse that triggered a wind slab avalanche on the slope below.  The second photo shows a long running crownline of a what was likely a storm slab avalanche, failing from the density changes within the storm snow.  Snowpack obs today showed the storm snow is consolidating nicely and shouldn't pose many issues in terms of avalanche danger until the next storm.  Wind slabs formed during the week due to SW winds will also gain stregnth this week but winds from the East Saturday and Sunday will form new wind slabs on SW-W-NW facing slopes which will likely be sensitive to human triggers for a few days.

Also of note, heavy rain up in the BWRA this past week has led to water flowing downhill and across the road, washing out the snowpack in certain spots leading to large gaps and drop-offs in the snowpack along Hyw 108 (photo 3).  Exercise caution when going up the road and look ahead for these traps. 

Avalanche Photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Light
Precipitation: 
Snow
Air temperature trend: 
Warming
Wind Direction: 
Northeast
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Started off partly sunny then clouds came in by noon and began to lower.  Light snow started around 2pm.