Weather will likely play an important role when you plan your trip to Ganvie, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually March and January, with an average temperature of 28°C, while the coldest months are August and July, with an average of 26°C. The rainiest months in Ganvie are June, July, May and September, with each month seeing an average of 222 mm of rainfall.