Apparently, "hole punch" clouds are not just for Eastern Washington.
Liem Bahneman saw my blog article from Monday showcasing the strange hole punch clouds over Wenatchee.
Turns out, there were some on this side of the hills as well.
But Liem captured the effect as more of a line -- likely caused by a plane on gradual approach to Sea-Tac or Boeing Field.
Here is a larger version of what he captured:
Better yet, here is video from his time lapse camera inside his home:
Just goes to show the atmosphere was in prime condition for this effect to be showcased.
To further show the point, check out this time lapse video from the UW Atmospheric Sciences camera on Feb. 28. Note also the gravity waves in the smooth cloud decks: