If you’re hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Mahahual: The hottest months are usually May and August, with an average temperature of 27°C, while the coldest months are January and December, with an average of 24°C. The rainiest months in Mahahual are June, September, October and August, with each month seeing an average of 204 mm of rainfall.