SP breaks temperature record after 64 years and Rio records 40.1°C; understand the causes of the “heat” in Brazil

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According to meteorologist Andrea Ramos, the warm air mass prevents the advance of cold fronts towards the southeast, making it difficult for air to renew and causing high temperatures. Andrea points out that the current situation is linked to a high-level cyclonic vortex, a phenomenon that creates atmospheric blocking and, therefore, the emergence of heat waves.

— The National Institute of Meteorology (Inmet) has issued two types of alert, valid until next Monday (29). A yellow, which covers part of Minas Gerais, and another orange, responsible for completely covering Rio and São Paulo. The second has a unique characteristic, it shows a heatwave that lasts between 3 and 5 days. — explains the meteorologist.

To be defined as “hot weather”, the current temperature must exceed 5°C above the climatological average expected for this time of year for approximately five days. According to Cesar Soares, meteorologist at Climatempo, the calculation must be made with figures obtained over at least 20 years.

— To know if a temperature is normal or not for the current season, we take an average of the daily and monthly averages over a period of at least 20 years. To measure the current temperature, we use ordinary thermometers at stations which have minimal impact. In other words, areas with fewer buildings, with vegetation and a shady place, he explains.

Andrea Ramos also points out that, to calculate the thermal sensation, we also take into account the temperature of the skin, which varies for each person.

— These high temperatures, intensified by these climatic conditions, further favor sensitive temperatures, those of the body. In the Southeast region, where there is extreme heat, low humidity and little wind, the thermal sensation can evolve up to 2 or 3 degrees above the temperature discovered in the common measurement.