Couple of years ago after a huge windstorm a number of stations, both FM & TV, were off the air in my area. They all shared a tower. Some were back on the air a couple of days later, others it was close to a week. I'm assuming that they lost electricity but also assumed they would have had a backup generator at the site. Also assuming that maybe the main antenna transmission lines could have been severed, a tree could have come down and crunched the transmitter shack, electric bill wasn't paid, squirrel/raccoon/other animal could have gotten in there and became a crispy critter by shorting everything out. Never did find out what the issue was, everybody remained mum about it when I started asking questions.