Inmet issued the alert on Friday for above-average high temperatures starting this Saturday in the capital, Brasília, and in the states of São Paulo, Rio de Janeiro, Paraná, Maranhao, Minas Gerais, Bahia, Mato Grosso, Pará, Goiás, Mato Grosso do Sul and Tocantins.
Record temperatures and wind chill indexes are expected in Rio de Janeiro and in the country's and South America's largest city, Sao Paulo.
Inmet reported in a statement that the cities of Sao Paulo and Cuiabá, capital of Mato Grosso, had the highest winter temperatures since 1961.
The country, with a tropical climate and the most populated in Latin America, is under the effects of a phenomenon of extreme temperatures in a large part of its territory, with devastating effects in the southern region, where the passage of a cyclone left 50 dead during September.
Due to the heat wave, the National Electricity System Operator forecasts a 5.8 percent increase in electricity consumption for September, according to the local newspaper "O Globo."
Beaches, rivers, waterfalls and public parks are full in most parts of Brazil, with temperatures ranging between 35 and 41 degrees Celsius. The Ministry of Health launched a campaign calling for hydration of the population and avoidance of extensive sun exposure.