Cold front wreaks havoc with rain of up to 180 mm, hail and gales

Heavy to intense rain and thunderstorms have hit Rio Grande do Sul since the beginning of the day as the effect of a cold front that advances across the state. In some cities, rainfall exceeded 100 mm with flooding and, individually, there was an accumulation of close to 200 mm, that is, a month and a half of rain in just a few hours. In other cities, the cold front also came with hail and windstorms, causing damage and inconvenience to the population.

MetSul Meteorologia warned that this Saturday would be highly unstable in the state of Rio Grande do Sul with a high risk of heavy rain and storms, as the cold front would encounter a mass of very hot air in front of it, forming clouds of great vertical development. A large mass of hot air covers Brazil with exceptionally high temperatures, which will block this cold front when it arrives in Santa Catarina.

According to data from automatic stations from the National Institute of Meteorology, the accumulated rainfall in 24 hours until the end of this Saturday afternoon totaled 179 mm in Quaraí, 106 mm in Rio Grande, 89 mm in Caçapava do Sul, 83 mm in Livramento , 77 mm in Capão do Leão, 73 mm in Canguçu, 64 mm in Dom Pedrito, 50 mm in São Gabriel, 48 mm in Bagé and 44 mm in Camaquã.

Although there was an official record of 83 mm in Livramento, the Uruguayan Meteorology station recorded 122 mm in the neighboring city of Rivera until 7 am today. Several measuring points at the Uruguayan Institute of Meteorology in the north of the country and around the border with Rio Grande do Sul recorded accumulations of 100 mm to 200 mm.

Stations of the National Disaster Monitoring Center also noted excessive marks with 171 mm in Quaraí, 112 mm in Pedro Osório, 98 mm in Capão do Leão, 91 mm in Arroio Grande, 82 mm in Encruzilhada do Sul, 79 mm in Canguçu, 69 mm in Dom Pedrito and 52 mm in Camaquã.

With volumes very high, several cities in the south and west of the state have faced flooding in the last few hours. In Livramento, last night, the streets looked like rivers with the flood that flooded parts of the city, especially the lower ones. Pelotas was another city that had flooding in its urban area.

In the late afternoon of this Saturday, heavy rain began to hit the Porto Alegre region and the metropolitan area with greater intensity as colder air advances from the South and forms heavier clouds from the Center to the North of the state. It had already rained heavily in the middle of the afternoon, even causing an aircraft to crash into Salgado Filho, but the most intense rainfall came in the late afternoon in the capital region.

Storms with wind and hail

The meeting of the cold front with the hot air mass favored isolated storms in Rio Grande do Sul, including the formation of isolated superstorm cells in the state with destructive wind and abundant hail. With a strong hot and dry North wind, brought by an intense low-level jet stream, the temperature reached maximums of 33ºC to 35ºC in the Northwest in the afternoon.

Santa Cruz do Sul was the city most hit by storms this Saturday afternoon. In the early afternoon, a severe storm with destructive wind and large amounts of hail hit Santa Cruz. According to Gaz portal informationmore than 640 houses in the city suffered damage, but the number is expected to increase.

The Civil Defense of Santa Cruz do Sul had to set up a task force to help people affected by the storm. By the end of the afternoon, almost seven thousand meters of tarpaulin had already been distributed to residents. There were roofs, fallen trees and lack of electricity in Santa Cruz and neighboring cities, such as Vera Cruz.

In Porto Alegre and the metropolitan region, where the temperature was close to 31ºC even with overcast skies, the first wave of instability came in the middle of the afternoon with locally heavy rain, despite being short-lived. Several aircraft remained in orbit waiting to land in Porto Alegre and an Azul flight even made a go-around, a normal procedure in aviation.

In the late afternoon, a second period of stronger instability hit the region with heavy rain and lightning. In parts of Grande Alegre, heavy rain was accompanied by gusts of strong wind, as in Vale do Sinos. Several points in the metropolitan area received between 30 mm and 40 mm of rain, that is, a third of the average for the entire month in less than 12 hours.

Heavy rain and thunderstorms continue with the cold front

MetSul Meteorologia warns of the high risk of locally intense rain and isolated thunderstorms on Saturday night in the Northern Half of Rio Grande do Sul. There is a high risk, for example, for municipalities in the Serra region. Storms may also affect part of the Middle Plateau, Alto Jacuí and Missões. Areas further north, close to Santa Catarina, should only experience instability tomorrow.

Satellite image from 7pm this Saturday showed very heavy clouds advancing with the cold front through the Northern Half of Rio Grande do Sul and reaching Serra Gaúcha | METSUL

Many clouds cover the Center and North of Rio Grande do Sul and it is raining, even heavy in some places, due to a cold front this Sunday. In the West and South, the sun appears with clouds and the weather is more open in the South under cold air. There must be moments of improvement. Sunday starts off cold in the West and South, even with temperatures below 10ºC on the border with Uruguay and Campanha, but the day will be mild to pleasant in the state.

Next week will see more heavy rain and storms

MetSul insists that Rio Grande do Sul will be between colder air to the South and a powerful mass of hot air over Brazil throughout next week. Depending on the day, sometimes warmer air advances from the North to the state, sometimes colder air will move from the South to the Rio Grande do Sul territory with warm fronts and cold fronts.

Since it will be in the transition zone between the two air masses, hot and cold, instability will be frequent with the expectation of a lot of rain. The accumulated rainfall throughout the week in the state will be excessively high and will add to the voluminous rain that has already fallen, so that once again we reiterate that the risk is high that rivers and floods will occur in the state at the beginning of May. .

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