The year that Katrina and Wilma hit, we cruised in early December. Key West was still recovering - you could still see the aftermath - and we had to go to Costa Maya instead of Cozumel because the port had been damaged. It was a very active year and there were tropical storms and proto-storms brewing out farther to sea but nothing that came even close to land or the ship. I think that's pretty common even in years with a lot of activity. Wasn't even a problem with rough waters while at sea or at least nothing that even remotely impressed itself upon me. It's definitely possible to be cooler on CC in December regardless of that and we've found that a number of activities do get cancelled due to high winds (e.g., parasailing) but it usually only affects the smaller water craft that they use for such excursions. We've still been able to snorkel close to shore and spend time in the water.