Inside impact didn't happen.
There was a leak, previous owner silicone'd the crap out it.
The chain plates (3) are tied into a horizontal grid - which might explain the 't' shape.
The storm in June - Six Tornadoes Confirmed on June 13th
High water and a gust could have caused it, just don't know - if I took a hammer and hit it I'm real sure it look the same. My insurance co confirms if impact it's covered, if plates pulling it's not, unless the impact loosened the plates.
That's why I've got a thermal camera coming - no guessing and a certified surveyor to put in writing what caused what when.