Brazil Storm Alerts Explained for Visitors

BRAZIL · WEATHER SAFETY

Inmet, Brazil’s national weather institute, rates storm danger in three colours, and we suggest visitors in São Paulo and Rio de Janeiro adjust plans once orange appears. In rain and storm warnings, orange means 30 to 60 mm (1.2 to 2.4 inches) of rain an hour or 50 to 100 mm a day, with flooding among the risks.

On Monday, 9 November 2026 (Brasília time, UTC−3), Inmet listed six active or upcoming warnings, all yellow, none for São Paulo or Rio de Janeiro states. This guide uses Inmet’s own legend and the federal civil-protection alert pages to show how to read the colours and how to get alerts on your phone.

An Inmet orange alert signals dangerous weather, so this guide explains each colour, how to get warnings in São Paulo and Rio, and what to do during a stay.

Storms in the Southeast’s summer have caused some of Brazil’s deadliest disasters, and the Rio Times Brazil page tracks each one as it happens. Visitors face the same risks as residents, namely sudden street flooding and landslides on hillsides.

What Inmet’s Three Colours Mean

Inmet publishes its warnings on a public map at avisos.inmet.gov.br. Each warning carries one of three severity levels, shown as yellow, orange or red.

Yellow is “Perigo Potencial”, or potential danger, which Inmet defines as a potentially dangerous weather situation. It asks people to take care with weather-sensitive activities, stay informed and avoid unnecessary risk.

Orange is “Perigo”, or danger, a dangerous weather situation. Inmet tells people to stay very alert, check the forecast regularly, learn about risks that cannot be avoided and follow the advice of the authorities.

Red is “Grande Perigo”, or great danger, meaning weather of exceptional intensity is forecast. Inmet says damage is very likely, with risk to life, and tells people to follow official instructions and prepare for emergency measures.

How to Read an Inmet Warning

Inmet names the type of weather in each warning. “Tempestade” means a storm with rain, wind and hail, “Chuvas Intensas” means intense rain with wind, and “Acumulado de Chuva” means accumulated rain, which can span several days.

At orange, an accumulated-rain warning names the risks as flooding, landslides on slopes and overflowing rivers in cities with such risk areas. An orange storm warning instead lists power cuts, crop damage, fallen trees and flooding.

Every warning also lists a start and end time and the affected municipalities. One “Acumulado de Chuva” warning for Bahia state, for example, runs from 10 to 13 November 2026.

Look for your own municipality in the list, because a warning for a state can leave your city out. São Paulo and Rio de Janeiro are both the name of a city and of a state, so read the municipality line carefully.

Why São Paulo and Rio Flood and Slide

Inmet’s orange text describes the usual damage: street flooding, landslides and swollen rivers in cities with risk areas. Two recent disasters in the states of Rio de Janeiro and São Paulo show the human cost.

In February 2022, rain-triggered landslides in Petrópolis, a hill city in Rio de Janeiro state, killed more than 230 people. In February 2023, floods and landslides on São Paulo state’s northern coast killed about 65 people, most of them in São Sebastião.

Both disasters struck in February, high summer in the Southern Hemisphere. São Paulo state’s Defesa Civil also issued a severe-storm alert for 11 and 12 September 2026, so warnings are not limited to the peak months.

São Paulo’s city emergency centre, the CGE (Centro de Gerenciamento de Emergências Climáticas), publishes a live count of flooded points and runs a 24-hour line at (11) 3396-6739. On 9 November 2026 its page showed zero active flood points.

Inmet’s colours are a national system, so the same warning list covers both cities. Check the municipality line for the city you are in.

A joint bulletin of 29 October 2026 from Inmet, Cemaden, Brazil’s disaster-monitoring centre, and partner agencies says El Niño should last until at least early 2027, strong to very strong. For November to January it sees above-average rain as likelier in the South and parts of the Southeast.

How to Get Alerts on Your Phone

Brazil has several alert channels, and the best set-up combines two or three. The steps below come from the federal Ministry of Integration and Regional Development, which oversees civil protection, São Paulo state Defesa Civil and Inmet.

For SMS you need a Brazilian CEP, such as your hotel’s, while cell broadcast needs no registration at all. The ministry does not say whether a foreign SIM card can send the SMS or whether phones sold abroad receive the broadcast, so keep WhatsApp or Telegram as a backup.

What to Do During a Stay

Inmet attaches instructions to each warning. At yellow, it says not to shelter under trees in wind, and to avoid using appliances plugged into the wall.

For orange accumulated-rain warnings, it says to avoid facing the bad weather, watch for changes on slopes and, if possible, switch off electrical appliances and the main power panel. For orange storm warnings, it says not to shelter under trees or park near transmission towers and billboards.

At red, Inmet says to switch off appliances and the main power panel, and to put documents and valuables in plastic bags if a flash flood strikes. If great danger is confirmed, it says to seek shelter and avoid staying outdoors.

Insurance and Flight Disruption

Check whether your travel insurance covers weather delays and natural disasters, and read how the policy words them. Cover differs between policies, so ask the insurer before you leave rather than after a storm is named.

Heavy rain can delay or cancel flights at São Paulo and Rio airports, and each airline sets its own rebooking terms. Check the carrier’s app before heading to the airport and keep digital copies of your passport and policy.

US citizens can enrol in the State Department’s Smart Traveler Enrollment Program, known as STEP, to receive embassy alerts while abroad. For longer stays, the Rio Times guides to São Paulo and Rio de Janeiro cover housing and neighbourhoods, and the November guide for Rio lists what is on.

What Is Not Known

The October El Niño bulletin gives no rainfall figure for the city of São Paulo or Rio de Janeiro. How wet the coming months will be in each city is open.

The ministry does not say whether a foreign SIM card can register for 40199, or whether phones sold abroad, including US models, receive cell-broadcast alerts. Its page also describes cell broadcast as coming soon in one place, so availability may vary by municipality.

Frequently Asked Questions

What does an Inmet orange alert mean?

Orange is “Perigo”, a dangerous weather situation, and for storms it means 30 to 60 mm of rain an hour or 50 to 100 mm a day. Inmet asks people to stay very alert and follow the authorities.

How do I get storm alerts in São Paulo or Rio?

Text your CEP, the Brazilian postal code, to 40199 for Defesa Civil SMS alerts, or save the WhatsApp number 61 2034-4611. Compatible phones in a risk area are also meant to receive cell-broadcast alerts without signing up.

Is a red alert worse than orange?

Yes, red is “Grande Perigo”, meaning weather of exceptional intensity is forecast and damage is very likely. Inmet tells people to follow official instructions and prepare for emergency measures.

Which phone numbers does Inmet give?

Inmet’s warnings point to Defesa Civil on 199 and the fire brigade on 193 for more information. São Paulo’s city emergency centre also runs a 24-hour line at (11) 3396-6739.

What is the rain outlook for the 2026 to 2027 summer?

A joint federal bulletin expects a strong to very strong El Niño into early 2027, with above-average rain likelier in the South and parts of the Southeast. It gives no figure for São Paulo or Rio.

Sources: Inmet, Avisos Meteorológicos map, legend and warning texts, read 9 November 2026; Inmet, e-mail warnings, read 9 November 2026; Ministry of Integration and Regional Development, disaster alerts (SMS 40199, WhatsApp, Telegram, cell broadcast), read 9 November 2026; São Paulo state Defesa Civil, SMS registration FAQ, read 9 November 2026; CGE São Paulo, flood points and 24-hour line, read 9 November 2026; El Niño Panel bulletin no. 5 (Inmet, Cemaden and partner agencies), 29 October 2026.