From an email:
We were still hesitant of our results from our snowpit so we decided to cut a cornice that would drop onto the slope below, which I'm estimating to be 40 degrees. We released a cornice that tumbled downslope. The cornice went roughly a quarter of the way downslope before triggering a hard slab avalanche that broke just below the corniced ridgline. The avalanche propagated on both sides of the path and propagated further downslope. The avalanche ran into the flats and flanked in two directions once the slope widened (which I've included in the map below).
We were unable to assess the crown in detail since we weren't comfortable with the amount of hangfire above, but estimate it to be 150 feet wide, running 1000 feet slope distance and roughly 600 vertical feet. The avalanche failed on the persistent weak layer interface that we had doubts about.
20200307 @ 12:30pm
Number of slides
Hard slab avalanche
Cornice fall triggered by human or explosive action
c-A controlled or intentional release by the indicated trigger
O - Old snow
Slab Thickness units
Single / Multiple / Red Flag