Planning for the weather is a good way to make your trip to São José do Rio Preto relaxing and enjoyable, especially when you're splurging. The hottest months are usually September and October with an average temp of 78°F, while the coldest months are July and June with an average of 70°F. The rainiest months in São José do Rio Preto are January, December, February, and March, with each month seeing an average of 9 inches of rainfall.