Planning for the weather is a good way to make your trip to Nakhon Si Thammarat relaxing and enjoyable, especially when you're splurging. The hottest months are usually May and June, with an average temperature of 28°C, while the coldest months are January and February, with an average of 26°C. The rainiest months in Nakhon Si Thammarat are November, December, October and January, with each month seeing an average of 320 mm of rainfall.