Caribbean vs Fiji weather for August honeymoon

We’re planning our honeymoon for August (next year) and want to do a week at an all-inclusive style tropical resort. Originally, we were thinking Antigua or St. Lucia but I’ve been reading that August is peak rainy season. One alternate we’re considering is Fiji since it wouldn’t be their rainy season.

Does anyone have experience with what weather was like traveling to the Caribbean in August? Trying to decide if we should stick with our original idea or switch to planning for Fiji.