I guess that you mean that the port captain has already announced that the port will be closed this coming Thursday, and maybe to all vessels of any size?
No one knows where it will go exactly and won't until Thursday, but if this monster doesn't change direction by tomorrow, I suspect that many boats will be unavailable as they begin pulling them out of the water, as ferries prepare to leave for Cancun on Wednesday, and cruise ships start dodging it as slow as they move. I suggest that all tourists on the island leave it tomorrow if possible and all inbound travelers abandon those plans.