(Weather station: Lihue Lihue Airport, USA). To get a better understanding, contact a Kauai snorkel equipment supplier or snorkel tour company who have more knowledge than we do about the seasonal ocean patterns. We are planning our first trip to Hawaii in August 2020. Flying to Hawaii: How to Choose the Right Airport, Hawaii rainfall chart by month and island, Booking Hawaii Inter-island Flights or Ferry, 10 Best Free Activities and Sights on Oahu. The best time to visit is April, May, June, July, August, September, October, November, December. The lowest water temperature of 23.80C | 74.84F will be reached in February. Friends are recommending different islands, but all agree you cant go wrong with any choice. Weve visited Kauai in the months of February, April, May and October. The rain makes Hawaiis delicious produce grow and the flowers bloom. Summer starts here at the end of June and ends in September. Hardly anyone on this beach. //-->,