Weather will likely play an important role when you plan your trip to Ngoc Hien, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually April and March, with an average temperature of 29°C, while the coldest months are January and December, with an average of 27°C. The rainiest months in Ngoc Hien are October, September, July and June, with each month seeing an average of 350 mm of rainfall.