Thunderstorms accompanied by gusts of wind and even a chance of hail are among the forecasts from the National Institute of Meteorology (Inmet) for practically all of Rio Grande do Sul (including the Metropolitan Region of Porto Alegre) and also for part of the territories of Paraná and Santa Catarina. The cold front in southern Brazil could generate other days of instability this week. Inmet draws attention to cities such as Porto Alegre, Santa Maria, Pelotas and Uruguaiana, where there is a risk of heavy rain and the possibility of isolated hail.  Related news: Inmet has a storm warning in the South this morning. Inmet remains alert for the cold; South and Southeast may have frost. Inmet issues yellow warning for temperature drop in 12 states and DF. In Porto Alegre, for example, cloudy weather is forecast for the entire week, with a minimum temperature of 14ºC. Curitiba is also forecast to be unstable and with a maximum temperature of 16ºC.  Also this Monday, rains are expected to arrive in the west and interior of Santa Catarina, including the cities of Chapecó, Concórdia, Xanxerê and Lages. In Paraná, the greatest risks are in the cities in the west, southwest and south of the state, including Cascavel, Foz do Iguaçu, Guarapuava and Pato Branco. Rain and cold across the country The agency also predicts potential danger of intense rain for this Monday morning in the North of the country, including most of the states of Pará and Amazonas, and Amapá, in addition to the south of Roraima. In the Southeast, São Paulo (SP) should have a minimum temperature of 9ºC on Tuesday (9), and Belo Horizonte may also experience a cold of 11ºC. In the Central-West, Brasilia residents can also feel the cold of 11ºC this Monday and 13ºC this Tuesday. From Wednesday to Friday, the capital of Brazil should have many clouds in the sky.