If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Akumal: The hottest months are usually August and July, with an average temperature of 28°C, while the coldest months are January and February, with an average of 24°C. The rainiest months in Akumal are June, September, October and August, with each month seeing an average of 194 mm of rainfall.