I'll start off with 3:
1) Hate when they interview "passersby" about a particular topic...who cares what some dOOd thinks as he's walking by? Most people on the street are clueless anyway....
2) Hate when the weather person spends a half minute (or more) rattling off every city's temperature within' a 100 mile radius when there'[s only a 3 degree difference between them all.
3) Hate when they show file footage during a storm...and don't label it as such. You see roofs being blown in the video from a storm that occurred years ago.