Although we run treks all year round, typically, the months of January & February and also September & October are considered to be the best months in terms of dry weather and moderate temperatures. June to August are also good months in terms of dry weather but temperatures will be much cooler.
Tanzania has two "rainy seasons" - the "short rains" during November and December and the "long rains" during March to the end of May. These are the rainiest months and climbing conditions are not as favourable. We recommend climbing via the Rongai Route in the wetter months, since the northern side of the mountain receives less precipitation.