ZANZIBAR — WEATHER & CLIMATE ⛵️ Generally the main rainy season, or the 'long rains', last during March, April and May. Afternoon tropical downpours are the norm – which can be heavy on any of the islands. The humidity is high and daily temperatures reach the low-mid 30°s. The long dry season, when rainfall is fairly unusual, lasts throughout June, July, August, September and October. Temperatures vary hugely with altitude and location, but it's usually a fine, clear sky and sunny weather – it's