Planning for the weather is a good way to make your trip to Ambanja relaxing and enjoyable, especially when you're splurging. The hottest months are usually December and March with an average temp of 81°F, while the coldest months are July and August with an average of 76°F. The rainiest months in Ambanja are January, February, March, and December, with each month seeing an average of 19 inches of rainfall.