Brazil Storm Warning: Eight Capitals Under Alert

Brazil's national weather service, the National Institute of Meteorology (INMET), has a yellow storm warning in force on Wednesday (Oct. 28), rated "Potential Danger," for 1.861 municipalities in seventeen federal units: Goiás, Minas Gerais, Paraná, Pará, Tocantins, Maranhão, Piauí, Mato Grosso, Acre, São Paulo, Pernambuco, Mato Grosso do Sul, Ceará, Rondônia, Bahia, Amazonas and the Federal District. The alert runs from midnight to 11:59 p.m. Brasília time and covers eight state and federal capitals: Rio Branco, Brasília, Goiânia, Cuiabá, Campo Grande, Teresina, Porto Velho and Palmas.

For the warning area, the institute forecasts rain of 20 to 30 millimeters per hour, or up to 50 millimeters over the day, winds of 40 to 60 km/h and hail. It rates as low the risk of power outages, crop damage, falling tree branches and flooding. If winds gust, INMET advises people not to shelter under trees, because of the slight risk of falling limbs and lightning, and not to park vehicles near transmission towers or billboards. It also recommends avoiding electronic devices plugged into an outlet. More information is available from Brazil's Civil Defense (phone 199) and the Fire Department (phone 193).

A separate yellow warning for accumulated rainfall has also been in force since 12:01 a.m. today and runs until 11:59 p.m. on Thursday (Oct. 29). It covers 116 municipalities in Bahia, among them Salvador. The institute expects rain of 20 to 30 millimeters per hour, or up to 50 millimeters per day, with a low risk of flooding and small landslides in cities with high-risk areas. It advises people to avoid going out in the bad weather and to watch for changes on hillsides.

Forecast for the capitals today

According to a model from the Norwegian weather service MET Norway, Goiânia has the highest rainfall estimate among Brazil's 27 capitals for today: 27.6 millimeters. Salvador follows with 12.4 millimeters and Cuiabá with 10.6 millimeters, while Brasília has 8.2 millimeters. These are model estimates, not measurements, and the figures may change during the day. INMET's city forecast for Goiânia calls for a chance of isolated rain in the morning, isolated showers and thunderstorms in the afternoon and isolated showers in the evening, with a low of 21 °C and a high of 28 °C.

In Brasília, INMET puts the low at 19 °C and the high at 27 °C, with isolated showers in the morning and evening and isolated showers and thunderstorms in the afternoon. Salvador has a low of 25 °C and a high of 31 °C, with isolated showers in all three periods of the day. In Cuiabá, the low is 25 °C and the high 34 °C, with a chance of isolated rain in the morning and isolated showers and thunderstorms in the afternoon and evening. Palmas (low 23 °C, high 34 °C), Porto Velho (24 °C and 35 °C) and Rio Branco (20 °C and 32 °C) also have showers, with thunderstorms during part of the day. In Campo Grande, the low is 20 °C and the high 27 °C, and INMET points to a chance of isolated rain in the morning and isolated showers and thunderstorms in the afternoon. Teresina has isolated showers and thunderstorms in the morning and afternoon.

A warning covers the whole area at once, so the forecast for a single city can be milder. Porto Velho, for example, is inside the warning area, yet the model estimates only 0.4 millimeter for today. In such cases the warning is the official reference for the risk of heavy rain, wind and hail.

Curitiba and São Paulo have a cooler day. Curitiba has a low of 11 °C and a high of 22 °C, with heavy cloud cover. São Paulo has the lowest forecast high among the capitals, 20 °C, and a low of 12 °C. Florianópolis has a low of 16 °C and a high of 24 °C, and Porto Alegre 15 °C and 25 °C. Rio de Janeiro is forecast at a low of 17 °C and a high of 27 °C, with a chance of isolated rain in the afternoon, and Belo Horizonte at 15 °C and 26 °C, with heavy cloud cover.

At the other extreme, Teresina has the highest forecast high among the capitals, 39 °C, with a low of 26 °C and a minimum relative humidity forecast of 30%. Boa Vista follows with 38 °C, and Belém is at 36 °C.

Thursday (Oct. 29)

INMET has already issued a yellow storm warning for tomorrow, from midnight to 11:59 p.m., now covering 2.777 municipalities in seventeen federal units: Goiás, Minas Gerais, Paraná, Santa Catarina, Tocantins, Mato Grosso, Acre, São Paulo, Mato Grosso do Sul, Rio Grande do Sul, Rondônia, Pará, Amazonas, Rio de Janeiro, Espírito Santo, Bahia and the Federal District. Twelve capitals are in the area: Rio Branco, Brasília, Goiânia, Cuiabá, Campo Grande, Belo Horizonte, Curitiba, Rio de Janeiro, Porto Velho, Florianópolis, São Paulo and Palmas.

In the city forecast for tomorrow, São Paulo has a low of 16 °C and a high of 18 °C, with overcast skies and isolated rain. The MET Norway model estimates 25.7 millimeters of rain for the city, the highest estimate among the capitals for the day, ahead of Campo Grande (19.9 millimeters), Goiânia (13.1 millimeters) and Rio de Janeiro (12.9 millimeters). Curitiba has a low of 12 °C and a high of 15 °C, with drizzle throughout the day. Rio is forecast at a low of 17 °C and a high of 26 °C, with drizzle in the morning and afternoon and isolated rain in the evening. Brasília has a low of 18 °C and a high of 28 °C, and Teresina again reaches 39 °C. INMET's storm guidance on wind, hail and lightning applies on the 29th as well, and the warning takes precedence over each city's individual forecast.

For Friday (Oct. 30), INMET's warnings panel shows a yellow storm warning for 2.430 municipalities and nine capitals: Brasília, Goiânia, Cuiabá, Campo Grande, Belo Horizonte, Curitiba, Rio de Janeiro, Florianópolis and São Paulo. These alerts may still be changed, canceled or expanded.

The temperatures and rainfall totals cited are forecasts. The warnings and forecasts were checked at around 7 a.m. on Oct. 28 (Brasília time), and the warning areas may change during the day.

Sources

• INMET: weather warnings panel
• INMET: city weather forecasts
• MET Norway: forecast data (CC BY 4.0 license)
• RaisLife: weather and forecast for the 27 capitals

Text by Rai, RaisLife's virtual reporter (artificial intelligence), with automated editorial review. Data: RaisLife weather panel.