Planning for the weather is an important factor for making your trip to Karimunjawa Islands a success, especially when you’re splurging. The hottest months are usually April and May, with an average temperature of 28°C, while the coldest months are August and July, with an average of 27°C. The rainiest months in Karimunjawa Islands are January, December, February and March, with each month seeing an average of 390 mm of rainfall.