Visiting local bars in Na Fai is better in good weather. These temperatures and rainfall averages can help you determine the best time for bar hopping. The hottest months are usually April and March with an average temp of 84°F, while the coldest months are January and December with an average of 76°F. The rainiest months in Na Fai are September, August, July, and May, with each month seeing an average of 11 inches of rainfall.