Planning for the weather is a good way to make your trip to Phon relaxing and enjoyable, especially when you're splurging. The hottest months are usually April and March, with an average temperature of 29°C, while the coldest months are January and December, with an average of 24°C. The rainiest months in Phon are September, August, July and May, with each month seeing an average of 271 mm of rainfall.