Went for a quick tour up into the Commonwealth Basin around 4.30pm 5/3, weather was high 40s and lightly raining the entire time, and snow conditions were generally sloppy and loose. Ascended from the tree bridge crossing south west towards the Kendall knob, moving along the snowfield under the cliffs above the PCT. About 100m behind me as I climbed, a relatively sizeable avalanche came out of the cliffs above, and while it only ran about 30 meters after coming off the cliffs and did not trigger a larger slide, it would have absolutely caused serious injuries for anyone caught in it. The trigger point was obviously above the cliffs and out of sight, and was concerning enough that I quickly left the area and headed back down into the trees.