The wind will rip the leaves up. Just wait for new leaves to come in, then trim the ugly ones off. Or trim the ugly ones off and wait for the new ones to come back. Either way, cannas are pretty forgiving that way.

Sounds like they just got a little beat up but it's no bog deal, just trim it back, give them a lot of water and a lot of sun and the leaves will be back in no time.

I've trimmed just the rough edges off with sharp scissors.