If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Ouidah: The hottest months are usually January and March with an average temp of 83°F, while the coldest months are August and July with an average of 78°F. The rainiest months in Ouidah are June, May, October, and September, with each month seeing an average of 8 inches of rainfall.