Cyclone and cold front bring rainfall exceeding 100 mm.

The passage of an extratropical cyclone and a cold front should cause storms and rainfall totals exceeding 100 millimeters between Friday (16) and Sunday (18) in areas of Southeast, Central-West and Northeast Brazil. According to the forecast released by Meteored, Minas Gerais, Espírito Santo, Bahia and Rio de Janeiro are among the states with the highest risk of high precipitation volumes.

On Friday (16), an extratropical cyclone is expected to act between the coasts of the South and Southeast regions, accompanied by a cold front. The combination of systems favors the formation of heavy clouds and maintains conditions for rain in different areas of the country.

According to Meteored, moderate rainfall is expected during the early morning hours in São Paulo, southern Goiás, and eastern Mato Grosso do Sul. In other areas of the Southeast and Central-West regions, the weather should remain overcast. Throughout the morning, the low-pressure center will strengthen and begin to move eastward toward the Atlantic Ocean. Even so, atmospheric circulation should organize moisture between western Central Brazil and eastern Southeast Brazil, favoring light to moderate showers.

In the afternoon, rising temperatures combined with humidity should contribute to the formation of storms. The main areas of concern are southeastern Bahia, central and eastern Minas Gerais, southern Goiás, and northeastern Mato Grosso do Sul. Warnings also extend to the entire coast of the Southern Region. In the Northern Region, Rondônia should experience irregular rainfall, while northwestern Amazonas remains subject to storms during the afternoon.

On Saturday (17), instability is expected to continue in several Brazilian regions. During the early morning, there is a forecast of showers in Rio de Janeiro, Espírito Santo, Minas Gerais, Bahia and Amazonas. In the morning, the sun should appear in some locations, with rising temperatures. In the afternoon, however, the heat and humidity may favor intense rain and storms in eastern Minas Gerais, in much of Espírito Santo, in the interior of Bahia, in Tocantins and in the south of Maranhão and Piauí.

In the Central-West region, rainfall intensity tends to decrease as the moisture corridor weakens. Even so, Goiás and Mato Grosso may experience light showers. Western Amazonas remains under alert for severe storms.

In the Southern Region, the forecast indicates more stable weather across most of the area. The exception is eastern Rio Grande do Sul, where the circulation of the extratropical cyclone should favor the transport of moisture and the occurrence of rain.

On Sunday (18), the cold front should move towards the Northeast and continue to influence weather conditions in areas of the North of the country. The forecast indicates a risk of storms and heavy rain in different states.

During the early morning hours, moderate showers, accompanied by thunderstorms and lightning, may affect northern Bahia, southern Piauí and Maranhão, northern Tocantins, the interior of Pará, and areas of eastern Amazonas. In the afternoon, the combination of heat and humidity should favor the formation of storm clouds. According to Meteored, eight states will be under alert for heavy rain and storms: Bahia, Piauí, Maranhão, Goiás, Mato Grosso, Tocantins, Pará, and Amazonas.

Between Friday (16) and Sunday (18), rainfall totals are expected to increase in areas of Minas Gerais, Rio de Janeiro, Bahia and Espírito Santo. The presence of a cold front in these regions may rapidly increase precipitation volumes over the days. According to Meteored's forecast, the sequence of periods of rain and overcast skies in northern Rio de Janeiro and on the border between Minas Gerais, Espírito Santo and Bahia may result in totals exceeding 100 millimeters.

High rainfall volumes increase the risk of disruptions such as flooding, landslides, and flash floods. In the interior of São Paulo and Minas Gerais, accumulations could reach 80 millimeters. Even in other regions, where forecasts indicate lower volumes, the rain may cause localized disruptions. Therefore, monitoring weather updates is important during the passage of these systems.