Tanzania has a generally comfortable, tropical climate year-round, although there are significant regional variations. Along the warmer and humid coast, the climate is determined in large part by the monsoon winds, which bring rains in two major periods. During the masika (long rains), from mid-March to May, it rains heavily almost every day, although seldom for the whole day, and the air can get unpleasantly sticky. The lighter mvuli (short rains) fall during November, December and sometimes into January. Inland, altitude is a major determinant of conditions. The central plateau is somewhat cooler and arid, while in the mountainous areas of the northeast and southwest, temperatures occasionally drop below 15°C at night during June and July, and it can rain at any time of year. The coolest months countrywide are from June to October and the warmest from December to March.
When to go
Tanzania can be visited during all seasons. The weather is coolest and driest from late June to September, although in July and August, hotels and park lodges, especially in the north, are at their fullest. October and November are very pleasant, with fewer crowds and a slowly greening-up landscape as the short rains begin in many areas. From late December until February, temperatures are high, but not oppressive. Watch out for high-season hotel prices around the Christmas–New Year holidays, as well as during the July-August peak.
During the main rainy season (March to May), you can save substantially on accommodation costs, and enjoy landscapes that are green and full of life. However, some secondary roads may be impassable, and this is the time when many hotels close for a month or so, especially along the coast. Malaria risk, especially in coastal and low-lying areas, also tends to be higher at this time.