Campos do Jordão is a city nearby where I live and due to its location in the mountains it has naturaly a fairly cool temperature during the summer but it gets very cold (for a Brazilian lol) during the winter with temperature less than -0ºC. It´s very known here for being the place where artists, famous people and Brazilian personalities come to spend the winter season wich last the entire month of July.
For this reason it´s impossible to go there during this time because the city get too crowded and things like restaurants, stores and cafes get very expensive - you are going to spend money even to park the car to walk through the city or the other alternative would be to leave the car in the street wich is inadvisable. I´m not sure but hotels there´s no more vagancies if you want to go there in July. One of the most interesting things is that Campos became a store window where beautiful branded goods stands are sat such as Mercedes, BMW, Honda, Suzuki, Nissan and many others.
The place is also known as the Brazilian Swiss since the enviroment remember Swiss as well as the archtecture of many places like mall and hotels.
It´s a very nice place to visit so if you are here in Brazil I recomend Campos do Jordão.