The weather in Samui in June is fantastic, providing the island with a mid-year mini high season. The anticipated 100mm of rainfall is less than both May and July and it is usually delivered in short, heavy deluges across about nine days as opposed to the lighter but more persistent rainfall of other times of the year. This leaves plenty of time in between to enjoy the longest days of the year, with 29°C/83°F temperatures and a declining relative humidity between 61% and 90%. The brief but powerful storms brought by the westerly winds obviously bring unsettled sea conditions with them, particularly along the west coast. While diving is still pretty good in the 28°C/82°F waters of the east coast, the other side of the island is best enjoyed by sailors and surfers.