I live in North Carolina and can vouch that rough sea seem to happen off the coast of NC (Cape Hatteras).
This has happened to me several times in mid October going to Bermuda (from NYC ) . I love the added motion while on a ship but not all cruisers feel the same as me.
The Bermuda run can be rough and has a reputatation for rougher
sea's than most regular (Florida)cruise destinations.
I can remember once sailing on the QE 2 watching other ships rolling and bobbing around while she handeled the Atlantic much more steady.
Enjoy your cruise