The weather almost year round is excellent in Antigua. You will find daytime highs around 29 to 30 C and at night maybe to 24C. The tradewinds should be well established again by the end of the month, so sailing should be good. There is always a chance of a little shower coming from passing cumilous clouds but they are very short lived and most squally weather will have subsided by then. Ignore what you see on the weather network and other on line weather sources, they always make it appear that there will be rain everyday. Not so. There is always a small chance of a passing shower but the sun will be back out within minutes.
From a flying point of view, Antigua is VFR almost every day of the year, except in the August/September period where passing tropical systems can make things a little wet for a day or so, once or twice a week.
Thousands of British tourists can't be wrong!
For a good summary of the daily weather to expect check
WindGURU: Antigua and Barbuda - Antigua
I use that site religiously and many surfers/wind surfers/kite surfers bet their days off on the accuracy of this site.
Enjoy your vacation in the sun!