Planning for the weather is a good way to make your trip to Sai Yok relaxing and enjoyable, especially when you’re splurging. The hottest months are usually April and March, with an average temperature of 30°C, while the coldest months are December and January, with an average of 26°C. The rainiest months in Sai Yok are September, October, August and July, with each month seeing an average of 193 mm of rainfall.