I have 2 neighbors who live across the street from me (fortunately). I'm in Dallas, not that far from you. Anyway I noticed the same thing with their pecans. Big and you wouldn't want one to hit you on the head, but not ripe. I think it was the same last year.
I have large oaks and have been hit by more than one very large acorn. They started falling a few weeks ago which seems a little early. However, you'd have to ask the squirrels re the ripeness. Maybe it's the always strange weather we have around here.
