One outstanding feature of winter in the southeast and southern regions of Brazil is the presence of thick morning fog. Between June and September the airports of São Paulo and Rio de Janeiro are often forced to halt their operations due to heavy fog. The international airport of Guarulhos in São Paulo (also known as Cumbica) was built on an area that in the tupi-guarani language means “dense fog”. No wonder the airport is often a victim of the phenomenon. When an airport is closed flights are diverted to other cities. Brazilian airports are not equipped with advanced instrument landing systems allowing pilots to land with no visibility.
Unfortunately for passengers arriving from Europe, the time of the arrival of the majority of planes from the northern hemisphere coincides with the formation of fog. Our advice is, if you are arriving in the southern states of Brazil early in the morning during winter (in the southern hemisphere) make sure you leave plenty of time if you are planning on catching a connecting flight right away.