About the tornado. Fantastical things happen all the time in movies and shows. A ton of movies have been made about natural disasters and the characters of those of course survive against great odds. It is possible the tornado wiped out all the zombies breaking in the barn without actually touching the barn, no. But for the sake of the show, why not. The problem is they didn't SHOW IT. Instead they cut scene out the most dramatic part of the night and instead took up the hour with a bunch of boo hooing and music boxes. Totally lame, they should air this during the daytime with all the other soap operas.
Ok sure, but what kind of standard are we holding the show to?
I don't think anyone went to see any of the disaster movies expecting realism. This is the highest rated show on television, think about that. It has better ratings that Breaking Bad had during any point. Maybe it's just me, but I would think the writing should surpass that of cheesy disaster flicks. Besides, a lot of these are very obvious to a lot of people -- hire 5 people to screen the shows and let them pick the stupid things apart.