A lot of it depends on the strength of the storm and the time of day it hits. Many of the hurricanes of the past few years either started late in the day or overnight, so the parks were open partial days for a couple days. After a storm, they will bring the parks back up in phases. Usually MK and Epcot are the first to open, then DHS, then AK (depending on any damage repairs that may be required). I think the worst storm in recent history was Hurricane Jeanne back in 2004. It took almost two days to clear the state, it was moving so slow. By comparison, Hurricane Charley was through in maybe three hours.