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In terms of precipitation, rainfall in Zanzibar ranges from 0.8 - 12.6 inches per month. April is typically the wettest month, when rainfall can reach 12.6 in. July is typically the driest time to visit Zanzibar when rainfall is around 0.8 in.
If weather is an important factor for your trip to Zanzibar, use this chart to help with planning. For those seeking warmer temperatures, January is the ideal time of year to visit, when temperatures reach an average of 82.4 F. Travelers looking to avoid the cold should look outside of July, when temperatures are typically at their lowest (around 75.2 F).