All ears says:
Blizzard Beach water park will be closed October 30-December 3 for its annual refurbishment.
Typhoon Lagoon water park will be closed December 4-March 17 for its annual refurbishment.
No plans for Aquatica to close as far as I know, their website says:
Aquatica is open year round; operating hours vary and are subject to change due to inclement weather. Please call 1-888-800-5447 for more information.
If its warm enough is another matter, we were there last week of Oct, not warm enough for us for water parks, Ok for 2-3 hours in the afternoon but too cool before lunch.