If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Ouidah: The hottest months are usually January and March, 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 Ouidah are June, May, October and September, with each month seeing an average of 198 mm of rainfall.