Getting an idea of what to expect from the weather in Hengchun will help you enjoy your stay to the fullest. The hottest months are usually July and August, with an average temperature of 28°C, while the coldest months are January and February, with an average of 22°C. The rainiest months in Hengchun are August, June, July and September, with each month seeing an average of 351 mm of rainfall.