Climate · News
Brazil Issues Storm Alerts Across 15 States as Rain Front Sweeps South, Center-West, Southeast
Published:
In brief
Brazil's National Institute of Meteorology (INMET) issued yellow storm alerts covering 15 states from October 21–22, 2026, warning of hail, winds up to 60 km/h and rainfall of up to 50 mm a day. The South region, especially Paraná and Rio Grande do Sul, faces the most sustained risk, with Mato Grosso do Sul also included under the Wednesday-afternoon regional alert.
Brazil's National Institute of Meteorology (INMET) placed 15 states under yellow storm alerts for October 21 and 22, 2026, as a new rain system moved from the South region into the Center-West, Southeast and parts of the North, according to the agency's own forecast bulletin and reporting by regional outlet dgabc.com.br.
The alerts, INMET's lowest of three severity tiers (yellow, orange and red), warn of rainfall between 20 and 30 millimeters per hour, or up to 50 mm over a day, along with winds of 40 to 60 km/h and hail in some areas, dgabc.com.br reported citing the institute's bulletin. INMET lists the associated risks as power outages, crop damage, fallen branches and localized flooding, though it classifies that risk as low.
Which states are covered
According to the INMET bulletin reported by dgabc.com.br, the Thursday, October 22 alert spans Acre, Amazonas, Espírito Santo, Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Rondônia, Roraima, Santa Catarina and São Paulo, including the São Paulo metropolitan area. A separate, narrower alert for Wednesday, October 21, running from 3 p.m. to 11:59 p.m., covers Mato Grosso do Sul, Paraná, Santa Catarina and Rio Grande do Sul.
INMET's own forecast notice for the two days, published on its portal, said the South region would see the heaviest activity, with storms moving into western Rio Grande do Sul, Santa Catarina and Paraná on Wednesday and spreading across all three states on Thursday. The Center-West, led by northwest Mato Grosso, and the Southeast, particularly eastern São Paulo, were forecast to see thunderstorms expand on Thursday. Acre and Rondônia in the North faced persistent rain with a yellow alert already on Wednesday, with Amazonas joining the broader alert on Thursday. The Northeast, by contrast, was expected to stay dry, with INMET flagging low-humidity conditions in interior areas instead.
South region faces the longest exposure
Paraná is covered by both alert windows: the Wednesday-afternoon regional alert alongside Mato Grosso do Sul, Santa Catarina and Rio Grande do Sul, and the broader 15-state alert on Thursday, according to INMET's bulletin as reported by dgabc.com.br. Both windows carry the same forecast parameters for the state: rain of up to 50 mm per day, winds of 40 to 60 km/h and possible hail.
In Rio Grande do Sul, INMET's yellow alert for Wednesday afternoon covers the Missões, Northwest and parts of the North and Fronteira Oeste regions, forecasting up to 50 mm of rain, winds up to 60 km/h and possible hail, according to Jornal Timoneiro's report citing the institute. The outlet said instability was expected to advance into western and northwestern parts of the state on Thursday, with rainfall potentially exceeding 70 mm in the Northwest region by Friday, October 23. A separate yellow alert specifically for Caxias do Sul and the state's northeast, valid all day Thursday, October 22, forecasts winds up to 60 km/h, hail and up to 50 mm of daily rain, O Tempo reported, noting INMET itself describes the associated flooding and power-outage risk as low under this alert level.
Earlier storm system in early October
The current alerts follow a separate, more intense storm system in the same region earlier in the month. A report by Exame, dated October 8, described yellow and orange alerts for Rio Grande do Sul with wind gusts exceeding 90 km/h, hail and forecasts of rainfall reaching up to 200 mm in 24 hours in parts of the state, tied to a low-pressure system and an extratropical cyclone forming off the coast of Argentina and Uruguay. Santa Catarina was also under an orange alert and Paraná under a yellow alert in that episode. That system is distinct from the October 21–22 alerts and involved higher alert levels (orange) than the current yellow-level warnings.
What officials and broadcasters are saying
Brazil's public broadcaster Agência Brasil flagged the broader pattern in an October 21 radio segment titled "Chuvas e tempestades avançam pelo Brasil a partir de quarta," reporting that rain and storms were advancing across the country starting that Wednesday, consistent with INMET's own bulletins about the front moving from the South into the Center-West and Southeast.
| Area | Alert window | Rain forecast | Wind/hail risk |
|---|---|---|---|
| Rio Grande do Sul, Santa Catarina, Paraná, Mato Grosso do Sul | Oct 21, 15:00–23:59 | up to 50 mm/day | winds to 60 km/h, hail possible |
| 15 states incl. São Paulo, Minas Gerais, Rio de Janeiro, Goiás | Oct 22, 00:00–23:59 | 20–30 mm/h or up to 50 mm/day | winds 40–60 km/h, hail |
| Northwest Rio Grande do Sul (Missões/Northwest) | Through Oct 23 | up to 70 mm (by Fri.) | winds to 60 km/h, hail |
What is still unclear
INMET's yellow-level alerts describe flooding and power-outage risks as low. No casualties, evacuations or infrastructure damage had been officially reported by INMET, Agência Brasil or the regional outlets reviewed as of October 21.
Questions
- Which Brazilian states are under storm alert this week?
- INMET's October 22 yellow alert covers 15 states: Acre, Amazonas, Espírito Santo, Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Rondônia, Roraima, Santa Catarina and São Paulo. A narrower alert for October 21 covers Mato Grosso do Sul, Paraná, Santa Catarina and Rio Grande do Sul.
- How much rain is forecast?
- INMET's bulletins point to 20–30 mm per hour or up to 50 mm per day in most alerted areas, with northwest Rio Grande do Sul potentially exceeding 70 mm by Friday, October 23.
- Is this the same storm system as the one in early October?
- No. A separate Rio Grande do Sul storm system around October 8, reported by Exame, carried orange alerts, gusts over 90 km/h and forecasts of up to 200 mm in 24 hours tied to an extratropical cyclone off Argentina and Uruguay, a more severe event than the yellow-level alerts now in place for October 21–22.
- What alert level is in effect, and what does it mean?
- The current warnings are INMET's yellow level, the lowest of three (yellow, orange, red), indicating conditions that require attention but, per the institute's own classification cited by regional outlets, a comparatively low risk of flooding or major disruption.
- Which region of Brazil is expected to stay dry?
- According to INMET's forecast notice, the Northeast region was expected to see stable, dry weather during this period, with the institute instead warning about low humidity in interior areas rather than rain.
How the world is telling it
- PortugueseBrazilian outlets (INMET, Agência Brasil, dgabc.com.br, O Tempo, Jornal Timoneiro) frame the story around official INMET alert levels and time windows, distinguishing the current yellow-level, multi-state system from a more severe orange-level, cyclone-linked event in early October reported by Exame.
Sources
- INMET — Previsão para quarta-feira (21) e quinta-feira (22)
- Agência Brasil — Chuvas e tempestades avançam pelo Brasil a partir de quarta
- DGABC — Inmet emite alerta amarelo para tempestade em SP e outras regiões do país
- O Tempo — Alerta amarelo para tempestade em Caxias do Sul (RS) prevê granizo e ventos de até 60 km/h
- Jornal Timoneiro — Inmet emite alerta de tempestade para regiões do RS com risco de granizo e ventos de até 60 km/h
- O Presente — Alerta de tempestade abrange quase todo o Paraná; confira as 323 cidades sob risco
- Exame — Alerta severo de tempestade: veja estados com risco de granizo e ventania
This piece was prepared with artificial intelligence and passed an automated source check before publication. If you see an error, ask for a correction. Request a correction or reply · How we make this
Related
ClimateArticle
Woolly Bears, Berry Crops and Fog: What Winter Folklore Really Predicts
Every autumn, folklore claims that woolly bear caterpillars, heavy fruit and nut crops and even August fog can forecast how harsh the coming winter will be. Wildlife agencies and botanical trusts say these signs actually reflect past weather and growth conditions, not future ones — meaning the folklore is rarely a reliable forecast.
ClimateNews
Super Typhoon Champi, 2026's Strongest Storm, Threatens Japan, Taiwan and China
Super Typhoon Champi reached sustained winds of up to 296 km/h on October 20–21, making it the most powerful tropical cyclone recorded on Earth this year by wind speed. Japan, Taiwan and eastern China are issuing warnings, suspending ferries and preparing evacuations as the storm tracks toward Okinawa, Taiwan's coast and China's eastern seaboard this week.

ClimateArticle
Polar Vortex Signals for Winter 2026-2027: What Forecasters Know So Far
A weakening signal in the stratospheric polar vortex has been detected for late October–November 2026, but meteorologists stress it is a slowdown, not a collapse, and cannot yet be tied to a specific cold wave. Longer-range models point to a bigger disruption risk in January–February 2027, driven by a very strong El Niño, while NOAA's seasonal outlook flags a competing factor that could keep the vortex stronger than usual.

ClimateNews
Flood Watch Issued as Storm Brings Heavy Rain, Debris-Flow Risk to Southern California
The National Weather Service issued a Flood Watch for parts of Southern California from Wednesday morning, October 21, through Thursday afternoon, October 22, 2026, as a storm moves through the region. Forecasters warn of rainfall rates up to 1 inch per hour, with 1.5 to 3 inches possible in south-facing mountains and foothills, raising the risk of minor flooding and debris flows near recent burn scars.