The hurricane Irma category 5, with winds it's over 280km/h can affect the riot servers on Florida.
Riot games warning that hurricane irma on the florida can disturb the servers whit login and chats the game, here on brazil!
"It's a natural fenomenal and because this, we don't have how to know the effects of passage the hurricane in the area (interruption of energy and internet connection are some examples that come to mind now)" -Riot Games