Observation: Portage / Placer

Location: Byron Glacier Trail

Route & General Observations

The last 1/8 mile of the established trail is covered in avalanche debris that released from both sides of the valley. The entire Byron valley is full of avalanche debris from the huge avalanche cycle that occurred in mid March. A series of storms from March 7th-24th dumped 27″ of rain at the Bear Valley (Portage) DOT RWIS weather station. This amount of rain is equivalent to ~30+ feet of snow in the upper elevations. There is still a very large cornice and a lot of snow in the upper elevations that hasn’t avalanched yet. Avalanche activity is expected to occur in the Byron Valley well into the spring due to sun, above freezing temperatures, and any rain. Unless you have avalanche rescue gear, advanced training and knowledge to evaluate an avalanche hazard we recommend avoiding Byron trail until summer. Byron Glacier Trail has had several near misses with hikers running away from avalanches in the spring and one fatality due to a snow cave collapsing.

Red Flags
Red flags are simple visual clues that are a sign of potential avalanche danger. Please record any sign of red flags below.
Obvious signs of instability
Recent Avalanches?Yes
Collapsing (Whumphing)?No
Cracking (Shooting cracks)?No
Observer Comments

Its hard to tell when the most recent avalanche occurred, likely over this last week with such warm temps and sun.

We measured the runout distance of where the debris initially crosses the trail, just before the first bridge. The runout distance was 36 degrees looking up at the starting zone on the SE facing slopes and 34 degrees on the NW facing slopes.

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.

Clear skies
Winds were 10-15mph
Temps upper 30Fs
No new precip

Snow surface

Firm and supportable melt/freeze surface

Photos & Video
Please upload photos below. Maximum of 5 megabytes per image. Click here for help on resizing images. If you are having trouble uploading please email images separately to staff.