Tanzania lies just south of the equator and on the whole enjoys a tropical climate, except in the high mountains (like Mount Kilimanjaro and Mount Meru) where temperatures can get below freezing, especially at night. Along the coast (see temperatures for Dar es Salaam), it stays quite hot and humid with heavy and reliable rainfall, especially during the rainy season. Tanzania has two rainy seasons, generally, the heaviest rains (called Masika) usually fall from mid-March to May and a shorter period of rain (called mvuli) from November to mid-January.
The dry season, with cooler temperatures, lasts from May to October.
Dar es Salaam stays warm and humid year round with some humidity offset by the Indian Ocean breeze. Rainfall can happen any month but the heavy rains fall from mid-March to May and November to January.
Dar es Salaam's Climate
Kigoma lies on the shores of Lake Tanganyika in Western Tanzania. Temperatures are quite steady year round, between 19 Celsius at night and 29 Celsius during the day.
The rainy seasons follow the general pattern in the rest of Tanzania but are a little more predictable, with most of the rain falling between November and April.
Arusha lies in the foothills of Mount Meru, Tanzania's second highest mountain. Arusha's elevation, at 1400m means the temperatures remain relatively cool year round and chilly at night especially during the dry season from June to October. The temperature ranges between 13 and 30 degrees Celsius with an average around 25 degrees. Arusha is the starting off point for safaris in Northern Tanzania (Serengeti, Ngorongoro) as well as those attempting to climb Mount Kilimanjaro and Mount Meru.