If you're hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Cacheu: The hottest months are usually March and April with an average temp of 81 °F, while the coldest months are January and February with an average of 81°F. The rainiest months in Cacheu are August, July, September, and October, with each month seeing an average of 16 inches of rainfall.