Planning for the weather is an important factor for making your trip to Phaya Yen a success, especially when you're splurging. The hottest months are usually April and March with an average temp of 86°F, while the coldest months are December and January with an average of 79°F. The rainiest months in Phaya Yen are September, August, July, and October, with each month seeing an average of 9 inches of rainfall.