We were at CTI Nov 15-22 last year and it only rained a little bit one day and we weren't even at the resort when it rained (we were zip lining)...not sure if this is typical or not but it made our vacation wonderful. I talked up the resort so much and knew someone else that was going in December and they had the complete opposite luck with weather.
We're headed to CSA Nov 14-21 this year..hopefully it doesn't rain every day again!!
We've gone for three years right around that time (late October to mid-November). It will likely rain a little bit each day, but sustained periods of rain seem to be more unusual and connected to passing storms in the area.
Our experience was: 2007, mostly sunny for the first week but windy and choppy, calmer and brief (10-minutes or so) showers about every afternoon for the second week; 2008, hit the edge of a tropical storm and got quite a bit of rain, heard reports that Negril was similar); 2009, sunny skies with 10-minute afternoon showers.
I don't think there's an appreciable difference in the weather between the north and west coasts but just the luck of the draw, at least when it comes to rain. The north coast does tend to be a bit windier.
In any event, we're heading back in November (12-20, I believe), and I'm hoping for the best, but even if it's overcast/rainy, it's better than November in Michigan!!