Planning for the weather is a good way to make your trip to Hat Yai relaxing and enjoyable, especially when you’re splurging. The hottest months are usually March and April, with an average temperature of 27°C, while the coldest months are February and January, with an average of 26°C. The rainiest months in Hat Yai are November, December, October and May, with each month seeing an average of 308 mm of rainfall.