I have been there for a couple of Carnivals in the past. There can be a parade/JumpUp at about any time and any place. I would suggest at least one trip to Carnival Village and if you can work it out, go into town for the "major parade" whenever that might be. We got into town early, parked and found a bar with a balcony and spent the day there. Expect traffic to be slow and plan accordingly. Good luck!
I think you also get the benefit of the absolute BEST weather and island conditions at this time period.
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