Meteorologists are monitoring a volatile weather pattern across South America that threatens to bring torrential rainfall and destructive winds to several Brazilian states over the coming days. The Instituto Nacional de Meteorologia (Inmet) has issued a series of alerts, with the most severe warnings centered on the South region, where accumulated rainfall could reach 100 mm.
The situation is particularly critical for the southwest and northwest regions of Rio Grande do Sul. Starting at 6 p.m. This Tuesday, these areas enter an “orange alert” for danger, indicating a high risk of severe weather. Residents are being warned of wind gusts that could hit 100 km/h, alongside the potential for hail, widespread power outages, and significant flooding.
This atmospheric instability is not limited to Brazil. Projections from Conexão GeoClima indicate that Argentina may experience even more extreme totals, with accumulations potentially exceeding 180 mm within a 72 to 84-hour window. The cause is a high-level atmospheric depression that creates a persistent pattern of instability, trapping moisture over specific regions for extended periods.
According to meteorologists from Conexão GeoClima, this is not an isolated storm event but a “persistent pattern” where rain remains stationary for hours or days. This specific configuration is particularly dangerous for vulnerable areas, such as steep slopes prone to landslides or low-lying urban zones susceptible to flash floods.
Regional Risks: From the Southern Border to the North
While Rio Grande do Sul faces the most acute danger, the impact of this weather system extends across the southern border and into the heart of the continent. Inmet has issued “yellow alerts” for the border regions of Paraná and Santa Catarina with Argentina, as well as southern Mato Grosso do Sul. In these areas, the forecast includes intense winds of up to 60 km/h and daily rainfall totals reaching 50 mm.
Simultaneously, the North and Northeast regions are grappling with the influence of the Intertropical Convergence Zone (ZCIT). This climatic phenomenon is driving frequent heavy rains and increasing the risk of severe thunderstorms across a vast stretch of the country. High humidity and maritime influence are amplifying the volume of precipitation in these tropical zones.
Conversely, the Southeast and parts of the Center-West are experiencing a starkly different climate. A high-pressure system has brought a mass of dry air to these regions, resulting in firm weather, elevated temperatures, and low humidity levels, providing a temporary reprieve from the storms affecting the rest of the country.
Understanding the Inmet Alert System
For those tracking the chuva torrencial nas próximas 72 horas: veja estados sob risco, We see essential to understand the color-coded warnings issued by the national weather service. A yellow alert signifies a potential for danger, requiring attention and monitoring. An orange alert indicates a higher level of risk, where the probability of damage—such as fallen trees, crop destruction, and infrastructure failure—is significantly increased.
The current distribution of alerts shows a widespread impact, with nearly every region of Brazil facing some level of risk due to the combination of the ZCIT in the north and the atmospheric depression in the south.
| Region | Alert Level | Primary Threats |
|---|---|---|
| RS (SW/NW) | Orange | 100km/h winds, flooding, hail |
| SC / PR Border | Yellow | 60km/h winds, 50mm daily rain |
| North / Northeast | Yellow/Orange | ZCIT-driven thunderstorms |
| SE / Center-West | None | Dry air, high heat |
Detailed State-by-State Risk Map
The following list details the current status of states under Inmet monitoring as of Tuesday. Residents in “orange” zones are urged to follow local civil defense instructions immediately.
- Amazonas, Ceará, Maranhão, Pará, Paraíba, Pernambuco, Piauí, Rio Grande do Norte, Rio Grande do Sul, Roraima: Yellow and Orange alerts.
- Acre, Alagoas, Amapá, Bahia, Mato Grosso, Mato Grosso do Sul, Paraná, Rondônia, Santa Catarina, Sergipe, Tocantins: Yellow alerts.
Impact and Safety Measures
The primary concern for authorities is the cumulative effect of the rain. When soil becomes saturated over a 72-hour period, the risk of landslides increases exponentially. In urban centers, the volume of water can overwhelm drainage systems, leading to rapid urban flooding that traps commuters and damages property.
Agricultural sectors in the South are particularly vulnerable. The combination of 100 km/h winds and hail can devastate standing crops, leading to significant economic losses for regional farmers. Power grids are similarly at risk, as saturated soil makes trees more likely to uproot and sever electrical lines.
For real-time updates and official warnings, citizens should monitor the Inmet Warnings Portal and follow the guidance of their respective state Civil Defense agencies.
The next critical checkpoint for meteorologists will be the transition of the atmospheric depression across the Southern Cone over the next 48 hours, which will determine if the rainfall totals in Rio Grande do Sul exceed the initial 100 mm projection. Official updates are expected to be released every 24 hours as the system evolves.
Do you have information on the weather conditions in your region? Share your updates in the comments below and share this report with those in the affected states.
