Weather is probably a major factor when you plan your trip to Phongprasan, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually April and May with an average temp of 82°F, while the coldest months are January and February with an average of 79°F. The rainiest months in Phongprasan are September, October, July, and May, with each month seeing an average of 10 inches of rainfall.