If you're hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Grand-Bassam: The hottest months are usually April and March with an average temp of 82°F, while the coldest months are August and September with an average of 77°F. The rainiest months in Grand-Bassam are June, May, October, and July, with each month seeing an average of 10 inches of rainfall.