Planning for the weather is a good way to make your trip to Poso relaxing and enjoyable, especially when you're splurging. The hottest months are usually October and September, with an average temperature of 25°C, while the coldest months are September and January, with an average of 25°C. The rainiest months in Poso are April, March, May and November, with each month seeing an average of 405 mm of rainfall.