The arrival of winter next Sunday (21) brings intense cold, with temperatures below 0°C forecast in the South and in areas of the Southeast during the month of July. However, despite the polar mass that advances across the country in the first few weeks, El Nino is expected to be intense and cause heat waves at the end of the season.
This year’s winter will begin under the influence of a strong cold front that should cause the first cold wave of the season. According to Climatempo, the polar air mass associated with the system should drop temperatures in the South, in areas of the Southeast and Central-West in the first week of the new season, in addition to causing a new episode of cold in Rondônia, Acre and southern Amazonas.
One of the strong polar masses expected for July should bring cold air to the region of Goiânia and Brasília, to the north of Minas Gerais and the extreme south of Bahia. Peaks of intense heat may occur in August in the Center-West and Southeast of the country. Very hot days should be observed in the North and Northeast.
In September, the risk of heat waves increases, influencing areas of the North, Northeast, Central-West and Southeast of the country.
According to Climatempo, the El Niño 2026/2027 phenomenon has a high probability of reaching , and could be among the most intense events observed since 1950.
Despite this, the rate should remain close to historical standards in the south of the country, as well as in a large part of Mato Grosso do Sul, São Paulo, central-south and eastern Minas Gerais, Rio de Janeiro and Espírito Santo.
In large areas of the Central-West, Northeast and North, temperatures are expected to be above average for the season. The forecast also indicates periods of intense heat, especially in the south and east of Pará, Tocantins, Maranhão, Piauí, western Bahia, Goiás, Distrito Federal and Mato Grosso.
Rains in winter
The advance of El Niño should change the climate in several regions of the country during the winter. In the South, the expectation is for an increase in atmospheric instability, with more cold fronts acting or forming over the region. As a consequence, episodes of heavy rain, storms and intense winds tend to occur more frequently throughout the season.
The forecast indicates above-average precipitation in the three southern states. The highlight is the southwest of Paraná, where the accumulated rainfall may be well above the values normally recorded for the period.
Even in regions that usually go through winter with a predominance of dry weather, such as the Southeast and Central-West, several episodes of non-standard rain are expected. The tendency is for the season to end with volumes slightly above average in most of these two regions.
The scenario also favors more rain in the center-south of Mato Grosso do Sul and in areas of the west, center-south and east of São Paulo. In the North, Acre, Rondônia and the south of Amazonas should record precipitation higher than that normally observed during winter.
In the Northeast, the typical pattern of dry and hot weather should prevail. In the eastern part of the region, however, the forecast indicates below-average rain in July, a month that is still usually rainy in several parts of the coast. The trend of reduced precipitation is expected to continue in August and September.
In the extreme north of the country, volumes should also be below normal in Roraima, in the north and northwest of Amazonas, in Amapá and in the north of Pará. In Tocantins and in the east of Pará, dry weather will predominate, as normally occurs during the season.
