Hi Dez,
Environments that are principally harbors will have only the calmer seas. I don’t think that they have an “ocean†area near the mouth, but I could be wrong.
Dover is the exception because there is a demarcation between the two harbors and the English Channel.
Until the mission editor is released, I think the only control you have over sea states may be the wind settings in free roaming.
Padstow is an excellent example:
Spawn Apollo outside the mouth of the river and set the wind speed to max.
The sea will moderate as you go down to the harbor.
Marseille is another.
Regards,
Marty