Planning for the weather is a good way to make your trip to San Sai relaxing and enjoyable, especially when you’re splurging. The hottest months are usually April and March, with an average temperature of 28°C, while the coldest months are January and December, with an average of 23°C. The rainiest months in San Sai are September, August, July and October, with each month seeing an average of 213 mm of rainfall.