It's hard to predict during hurricane season (June-November). We sailed during November 2 yrs ago and skirted a hurricane (30 ft. seas). Seas were rough for 3 days until we reached Virgin Islands.
We were prepared and took Ginger Powder Capsules and Bonine, and were fine but many people were not prepared and spent most of the time sick in their cabins. After the hurricane passed the seas were very flat.
Check the marine forecast before you go.
Also, even during calmer times, the first night out the boat can rock quite a bit when it crosses the gulf stream.