Interesting low elevation size 3.5 deep pwl slab avalanche, Stewart area, B.C.

[swissiphic]

Report from Bear Pass/Mez Lake north area. In addition to the recent deluge of widespread point release/loose snow surface wet slides noted in Bear Pass, deeper weak layers have become reactive north and immediately west of Meziadin Lake.

Report from the field indicated a remotely triggered large slab avalanche down 70-75cms on well preserved April 3 surface hoar. Avalanche triggered from ridgetop in alpine on what appeared to be north quadrant terrain...suspect NE.

Observed from roadside at Surprise Creek pullout just east of Bear Pass was a surprisingly large personally estimated size 3.5 deep slab avalanche that occurred naturally on a NE facing open glade well below treeline.

Elevation of start zone is 720+/- meters. Crown looked very deep from roadside with both some gouging down to ground and a secondary crown a bit lower looker's right on the slope.

Suspect the mid Dec or a Jan PWL as the failed weak layer. The avalanche crown was google earth measured at approx 250 meters wide.

The avalanche spilled into two separate confined tracks with the lowest elevation lobe reaching to valley bottom and travelling a bit of distance over very low angle/flat terrain. Total length of both lobes individual tracks/runouts was over 1 km respectively with a vertical drop of about 450 meters.

Personal ski touring program in the pass put on hold a week ago due to rising temps and remains on hold with the continuing phenomenon of the world crashing down.

Photos show crowns in red and two separate confined tracks in blue in first photo. Red arrow showing track/gully; runout zone of avy outlined in red in second photo.