You might spend a lot of your holiday inside, but if you want to see more of the area, looking at local weather trends is a good idea. The hottest months are usually January and December, with an average temperature of 26°C, while the coldest months are July and June, with an average of 18°C. The rainiest months in Foz do Iguaçu are October, December, January and May, with each month seeing an average of 215 mm of rainfall.