Hoi An is located in the centre of Vietnam; therefore, the weather has only two main seasons: rainy and dry seasons instead of four season like in the Northern Vietnam. Hoi An City has warm weather with the average temperature of 29 Degree Celsius.
In the summer, the highest temperature measured during day time is 38 Degree Celcius, usually from June to August. And the lowest temperature in summer is 21 Degree Celcius at night. Winter season from November to January brings coldest days with temperature from 19 to 24 Degree Celcius daily. This coldness seems to be of no concern for tourists from Northern Hemisphere.
Walking round Hoi an Town

It is annoying factor if you visit Hoi An in rainy season from September to January. It may happen typhoon and floods sometimes, which can accidentally delay your wonderful trip. During the damp season, the number of visitors coming Hoi An decrease dramatically.

On the other hand, in dry season from February to May, it is the best time to visit the town. The weather is really nice with warm and mild moderate temperature. It is low humidity, less rain and warm sunshine. It is time for going out and enjoy the ancient beauty of Hoi An. For those who love sunbathing, you can go to some famous beaches near Hoi An like Cua Dai Beach or An Bang Beach, delaying your trip to the end of May or beginning of Iune is recommended.

Moreover, it will be best time if you are lucky to arrive at the end of the 14th day of a lunar month. Hoi An will be much more charming with its Full Moon Festival and “Old Street Night” exclusively available on that day.