still time If one goes to Fiji or any other island group in the area (for example, Tahiti, Samoa or Cook Islands) for a beach vacation, then the best time to go is between April and early-October. The sun won't be directly overhead and blistering, heat and humidity won't be stifling. Also, it is not the rainy season during those months.
April/May and October/November are the best months for Fiji. Water temps. are pleasant without the chill you get from June to September. The same applies to the air temps. pleasant, quite warm but with cooler nights.
November through to March is humid and can be very hot, it is the wet season so rain is to be expected. It can of course rain at any time of the year and does.