NewRCcruiser

We were on Mariner last weekend. Seas were rough going from Port Canaveral to Nassau. They had the bags hanging around the ship and it certainly wasn’t the best night sleep. With that said, we docked in Nassau and the rest of the trip was smooth sailing.
Most importantly to us, we were able to dock in Coco Cay along with Navigator. It was very windy and the surf was rough but we still had a great day. A few ships (including bigger ones) missed the port in the days before us so we considered ourselves very fortunate.
My best suggestion is to go into your cruise optimistic. No one can control the weather, but your captain will do everything in their power to avoid it. If they can’t dock safely or if it’s going to be a miserable day, you just have to trust them and make the best of it.
Have a great cruise!

Another vote here for going in with an open mind.  On our very first cruise we did feel some motion and just put up with it and kept on with our vacation.  To make a long story short, turns out that was some of the roughest seas we have ever had, so everything has been a easy after that.  Our family actually even likes at least a little bit of motion, perfectly calm waters is almost too boring.
 
Weather and conditions will change and you can’t do anything about it so just enjoy.  All you can do is pack appropriately for cold And waterproof if you are doing something like an Alaska cruise, a jacket or umbrella for rainy days and sunscreen and swimsuits for everything else.  Get out there and enjoy!

We missed Costa Maya and it was a bummer, but the extra sea day was very relaxing. These ships are full of things to do or not. Like many others have said just enjoy and go with the flow. If you can have the mindset that the port itinerary is just a suggestion that helps.  

As others have said, Royal does not want to cancel any port (or Coco Cay) stop, but the safety of the passengers, crew and ship is a priority with Royal.
To get a good idea of anything brewing weather wise for a upcoming cruise, I like to watch/follow the Facebook page of Royal's Meteorologist.  His public page is "Chief Meteorologist James Van Fleet".   He usually posts a few days ahead of any upcoming storms or issues they are watching.
Safe travels, and have a great cruise.

CocoCay is found at the top of the Berry island chain within the Bahamas circled in red.

This is a consumer tool so it doesn't have the accuracy that the professional resources that Royal uses has.  Use it with a large grain of salt.  It's a forecasting tool but weather forecast at sea are notoriously incorrect because there are very limited reporting stations out there unlike across the United States on land.
There are many factors beyond simple wind speed they'll use, but if it's over 30 knots it's more likely they'll look into canceling the call. Green or blue colors are good, as it moves into the reds and purples it will be rougher out there.  They do their best to avoid that stuff, they don't want to put guests into bad weather if they can avoid it.