The first day of summer, this Sunday, will be marked by sun and heat in Rio de Janeiro and São Paulo, while Rio Grande do Sul is on alert for heavy rains at the end of the day, with a risk of thunderstorms, intense winds and hail. Forecasts indicate contrasts typical of the season, which officially begins with intense heat across much of Brazil.
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In the south of the country, the notable event is the arrival of a cold front in Rio Grande do Sul at the end of Sunday. The system, associated with the stretching of a low pressure center, is expected to cause lines of instability and storms, with the possibility of hail, electrical discharges and wind gusts that could exceed 80 km/h, according to meteorologist Andrea Ramos. Despite the heat all day, the rain is expected to increase in the late afternoon and evening. Paraná and Santa Catarina are not expected to feel the effects of the system until Monday.
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In the southeast, the scenario is one of firm weather in central areas and occasional instability in Espírito Santo and the far east of Minas Gerais. In these regions, rain is still forecast, which may be accompanied by gusts of wind and significant volumes. In Rio de Janeiro and São Paulo, Sunday will be warm and sunny, with no risk of rain, officially opening the summer season.
In the central region of the country, high temperatures, combined with humidity transported from the Amazon, favor the formation of rain showers. Mato Grosso, Goiás, Tocantins, Pará and the southern Amazon are among the areas with the highest probability of precipitation throughout the day.
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To the north, the action of the intertropical convergence zone begins to strengthen, increasing cloudiness and the risk of rain, especially in Amapá and northern Pará. The system also influences the Northeast regions, such as Maranhão, Piauí and Ceará.
In the Northeast, hot and dry weather predominates, especially in semi-arid areas. The presence of a dry air mass keeps the sky open, with few clouds and high temperatures, a typical scenario for early summer in the region.