Sounds more like an experimental military drone than Uncle Wally visiting from Mars.
Swamp gas coming off the lake.
I hope that's what it was, especially considering that it was seen to disappear so fast it punched a hole in the cloudcover. You bet it would be nice if it's one of ours -- because it's somebody's. The ods that these airline employees are doing this as a media prank are almost less than the liklihood of it actually being "Uncle Wally" from Mars!
Again, I hope you're right.