The graph below shows temperature and precipitacion in the city of Brasilia along the year. The orange line shows temperature in degrees Celsius, and the blue bars show accumulated precipitation by month in milimeters or rain.
Notice that seasons in the Southern hemisphere are the opposite of the Northern hemisphere. The Brazilian summer goes from (roughly) January to March, followed by autumn (May - June), winter (July - September) and spring (October - December).
The graph shows that:
1) temperatures in Brasilia range from a lowest of about 19 oC (66 oF) in winter to peaks of about 22 oC (72 oC) in summer;
2) Brasilia has a very well defined dry season, from May to August. In some years, the dryness reaches desertic levels; drinking plenty of water and using skin and lips protector is advised.