You'll likely spend much of your trip indoors, but if you're planning to venture beyond the casino, taking a look at local weather data can help you. 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 Wan Yai are July, August, September and June, with each month seeing an average of 343 mm of rainfall.