Inmet: weather forecast for Tuesday (21) and Wednesday (22)

The presence of low-pressure areas and the advance of a new frontal system are expected to intensify instability in southern Brazil starting this Tuesday (July 21). The National Institute of Meteorology (Inmet) warns of significant rainfall accumulations in Rio Grande do Sul, with a red alert indicating extreme danger, and does not rule out storms with hail between Tuesday and Wednesday in Rio Grande do Sul and Santa Catarina. 

North of the area of ​​greatest instability, strong winds persist between western and southern Mato Grosso do Sul and Paraná, as well as eastern and northeastern Santa Catarina, associated with the Low-Level Jet (LLJ). On Wednesday (July 22), these areas will be under a yellow warning of potential danger for storms due to the advance of the cold front. 

In the rest of the country, rain continues along the northeastern coast and moves inland on Wednesday, while showers occur in areas of the north and west of the North Region. On the other hand, in the interior of Brazil, low air humidity conditions persist during Tuesday afternoon in Mato Grosso, Goiás, the Federal District, Tocantins, and parts of Pará, Rondônia, Piauí, Minas Gerais, São Paulo, and Mato Grosso do Sul.

Northern Region

On Tuesday, the sky will vary from mostly cloudy across the region to clear in Tocantins. Showers are forecast in Amazonas, northern Pará, Amapá, Roraima, and western Acre, with a higher probability of occurrence during the afternoon. There is a yellow warning of potential danger for low relative humidity during the afternoon between eastern Rondônia, southeastern Amazonas, southern Pará, and much of Tocantins, where the sky will vary from partly cloudy to clear. 

On Wednesday, conditions will change little, but rain areas will move across the entire state of Acre and into northern and western Rondônia. Regarding temperatures, minimum temperatures in the capital cities will reach 22°C in Rio Branco (AC) and Palmas (TO), and a maximum of 36°C in Porto Velho (RO).

North East Region

The coastal strip of the Northeast region will continue to experience rain on Tuesday. There is a yellow warning for potential danger due to accumulated rainfall between the coast of Bahia and the coast of Sergipe, while between the coast of Paraíba and Rio Grande do Norte there is a yellow warning for potential danger due to intense rainfall. 

On Wednesday, areas of rain will move inland, with the possibility of isolated showers in north-central Maranhão and Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco (except for the far west), Sergipe, Alagoas, and along the coast of Bahia, particularly in the coastal strip between the Recôncavo Baiano and eastern Rio Grande do Norte.

In south-central Maranhão and Piauí, western Pernambuco, and much of Bahia, the weather remains stable, with mostly clear skies and no rain expected during this period. 

On Tuesday, there is a yellow warning of potential danger due to low relative humidity during the afternoon in southern Maranhão and Piauí and western Bahia. Regarding temperatures in the capital cities, the minimum temperatures forecast are 21°C in Salvador (BA), Aracaju (SE) and Natal (RN), while the maximum could reach 34°C in Teresina (PI).

Midwest region

On Tuesday, atmospheric stability will prevail over most of the region, with increased cloud cover in western Mato Grosso and much of Mato Grosso do Sul. There is a chance of isolated rain in southern Mato Grosso do Sul during the night. During the afternoon, there is a yellow warning for potential danger due to low relative humidity throughout the region, except in southwestern and southern Mato Grosso do Sul, where greater cloud cover favors higher humidity levels. Furthermore, southwestern and southern Mato Grosso do Sul remain under a yellow warning for potential danger of strong winds due to the continued intense Low-Level Jet (LLJ) in the region. 

On Wednesday, the advance of a frontal system will favor rainfall in western and southern Mato Grosso do Sul, where there is a yellow warning of potential danger for storms, with the possibility of hail. Regarding temperatures in the capitals, minimums of 14°C in Brasília (DF) and maximums of 35°C in Cuiabá (MT) are expected.

Southeast

Atmospheric stability will prevail during this period, with skies ranging from mostly cloudy along the coast of Espírito Santo and Rio de Janeiro to clear skies in the interior of São Paulo and western Minas Gerais. There is a yellow warning for potentially dangerous low relative humidity during Tuesday afternoon in western, southern, and Triângulo Mineiro regions, and in much of the state of São Paulo, except for southern São Paulo and the coastal strip. 

Throughout Tuesday night and Wednesday, increased cloud cover is expected in the south-central region of São Paulo state, with the possibility of isolated rain on the border with Paraná due to the approach of a cold front. In Minas Gerais, temperatures remain low at dawn, but there is no forecast of frost. Regarding temperatures in the capital cities, a minimum of 11°C is expected in Belo Horizonte (MG) and a maximum of 34°C in Rio de Janeiro (RJ).

South

For Tuesday, the forecast indicates storms in Rio Grande do Sul, with the possibility of hail in the western, central, and eastern parts of the state. Rainfall totals will be high in these areas. For this reason, the region is under a red warning for high danger of accumulated rainfall, particularly in municipalities such as São Borja, Santo Ângelo, Ijuí, Santa Maria, Santa Cruz do Sul, Porto Alegre, and Pelotas, where the predicted accumulations are higher. The rest of the state remains under an orange warning for dangerous storms. Meanwhile, western and southern Santa Catarina, along the entire border with Rio Grande do Sul, are under a yellow warning for potentially dangerous storms. North of this area of ​​greater instability, winds remain strong due to the Low-Level Jet (LLJ). Therefore, there is a yellow warning for potentially dangerous gales in western and south-central Paraná and in eastern and northeastern Santa Catarina. 

On Wednesday, the advancing cold front will bring rain and thunderstorms to south-central Paraná and maintain instability over Santa Catarina and Rio Grande do Sul. There is a yellow warning for potential storm danger in much of Paraná, except in the far north of the state, in Santa Catarina, and in the north and northeast of Rio Grande do Sul. Regarding temperatures in the capital cities, minimum temperatures of 13°C are expected in Curitiba (PR) and Porto Alegre (RS), and a maximum of 27°C in Florianópolis (SC). On Wednesday, maximum temperatures will not exceed 21°C in the capital cities of the Southern region due to the advancing cold front.