If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Thuan An: The hottest months are usually June and May with an average temp of 84°F, while the coldest months are January and December with an average of 72°F. The rainiest months in Thuan An are October, November, September, and December, with each month seeing an average of 19 inches of rainfall.