It's in the tropics, located about 6 degrees South of the equator. It means that the sun rises at 6am and sets at 6pm most of the year. The temperature variation is very small, and Bali does not have four seasons (except the hotel , of course) but has only wet season, typically from September to February, and a dry season for the other half of the year. But the difference is marginal; at the peak of the wet season you will see about a half-hour to an hour serious downpour in the afternoon, about perfect for a siesta. The rest of the time? Nice, warm temperature, especially with a twist of sea-breeze in the beaches of Kuta or Nusa Dua .