Observation: Public

Observation Details

Triggered Avalanches

Observed Avalanches

Signs of Unstable Snow

Observations

This report is from a few days ago, but may be relevant going into the hot weather this weekend.

We climbed forbidden via the west ridge, taking the snow finger to gain the notch. The night of 6/19 in boston basin was cloudy and warm with light precip and minimal wind, changing to clear skies with gusty winds before dawn. The snow failed to refreeze overnight, making for slow trail breaking through the avalanche debris that covered most of the route from high camp to the snow finger. Vehicle-sized snow chunks littered the glacier, presumably from massive glide avalanches off the south face of forbidden.

Around noon, we began to see and hear natural avalanches release from the steep south slopes of forbidden. These ranged from D1 loose wets to a larger, D2 or D3 glide avalanche off the eastern shoulder of Forbidden. On our descent from the notch around 2pm, we avoided the soft snow of the snow finger and rappelled the rib between the middle and easternmost "cat scratch" gullies, triggering D1 loose wet slides on the top snowy portion, and watching natural loose wet slides release around us and down the cat scratch gullies. We also watched another party set off D1 loose wets while descending near the "big rock" at the base of the gullies. No persons were caught in the avalanches.

Massive glide slabs remain on the south face of forbidden peak. Based on debris from previous avalanches, there may be potential for resulting slides to reach 6400' feet or lower, near the upper boston basin bivy sites (see photo).