I was at AS-sp in Dec 2010 and the temp was 36F/2C. People were swimming. I believe all the WDW pools are heated to around 83F/25C. Tepid bath water temp.

My suggestion; if it is cold out, have a designated shower person. Have them go to the room 5 minutes before you get out of the pool and turn on the shower in your room, open the hotel door and wait for you to run in.