if you have a papala you can sit under that and watch it rain, sit out on your balcony, take a nap, go grab lunch/snack, I have seen people just stay out in the water, the obvious that has already been mentioned go to the sports bar and have a drink, see if spa has any openings at that time and get a massage, oh and don't forget the casino.
What we have done when it rains is go up to the beach bars and sit and have drinks. Usually the rain passes pretty quickly and you can return to the beach. But get to know your bartenders at that time and the other CSA guests as well. You know they will make it a fun time.
The other thing we have done is gone to the hot tub...especially the one in the garden area. Just pull the umbrella up close to the edge so the rain doesn't run down your face.
Oct 2005, Dec 2006/Jan 2007, March 2008, Dec 2009/Jan 2010, June 2010, June 2011, June 2012