There's nothing like an all-inclusive vacation in Mto wa Mbu to revive you, especially when you know what kind of weather to expect. Here's some info to help you choose when to book: The hottest months are usually February and March with an average temp of 71°F, while the coldest months are July and June with an average of 65°F. July and August are the driest months while April and March are the rainiest months.