Observed this avalanche right in the middle of west monitor bowl. There were visible cracks propogating from the top of the bowl all the way down to the crown, which was hundreds of feet below the ridgeline. The crown appeared to be roughly a foot deep, although it was very far away and I did not care to venture to the middle of the bowl to find out. Very interesting to see the weak layer collapse for hundreds of feet until any major movement ocdcured.