Tanzania is situated very close to the equator, due to which the weather here is rather stable with a comfortable and well balanced climate. Never reaching extremely hot temperatures or very cold weather, the average annual temperature varies from +25°C in the south of the country and up to +27°C in the north.

It should be mentioned that on Kilimanjaro, as well as in places such as Ngorongoro Crater, the temperature does sometimes fall below zero, especially at night time, therefore it is necessary to take warm clothes to safari via Ngorongoro Crater. Many people try to avoid rainy seasons in Tanzania, of which there are two: the longest first one falls between the ends of March and May; the second one is between the end of October and the first half of December. They are commonly referred to as “long-” and “short rains”, respectively. Interestingly, the weather in Tanzania in December is hot and wet at the same time. The rainy season is marked by heavy precipitation. The table below gives an approximate annual estimation.
The average annual precipitation (mm) in Tanzania:

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
49 30 85 153 126 32 13 18 21 48 132 75

A lot of travelers ask “When does the rainy season end?” without realizing that all major TV companies such as Discovery and National Geographic choose the rainy season to film their stories, since that is the time when the local nature is at its most colorful, the grass is lush green and, most importantly, there are few other groups touring so that you can get top-notch photos. One might wonder what advantages would a trip to Tanzania in the rainy season has to offer?
Planning your trip to Tanzania during the dry season you must be prepared for the heat outside and dust on the dry roads. For the most part, 50% of the dust penetrating the interior of your vehicle comes from other passing jeeps during safari.
Another advantage of traveling during low season is the lower cost of accommodation and safaris alike. Accommodation is one of the main contributors to the high price for price for Tanzania safari adventures but during low season prices go down, making it possible to save considerable amounts of money while enjoying the comfort of nice hotels.
Among the disadvantages of low season, we can mention only one:-
due to poor road conditions more remote parts of the Serengeti National Park are inaccessible. Then again, they are seldom visited during high season too, due to the remoteness of these areas. In wet season many hotels in Tanzania are closed for annual maintenance, especially in Zanzibar.