Oeiras fire, August 2026 Oeiras, Colônia do Piauí
The fire started on 23 August 2026 in Oeiras, Brazil, and satellites saw it burning for 38 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 21,063 hectares from heat detections, spread across 2 municipalities.
It is the 23th largest in Piaui since 2016 (of 804 with a page). Number 24 in Brazil in 2026, of 751.
Compare with…
- Burnt area
- 21,063ha
- GWIS perimeter (Copernicus)
- Duration
- 38days
- 23 Aug 2026 – 29 Sept 2026
- Municipalities hit
- 2
- municipalities
- Started on
- 23 Aug
- 2026
- Heat detections
- 778
- in a single hotspot: 248 MW
- Danger at start
- 52
- Extreme · FWI index
- Average daily power
- 270MW
- detected power per day, on average
Where it burned
How it evolved, day by day
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
It had gone 31 days without rain (1 mm or more) when it started.
This area had burned before
83% of the perimeter overlaps earlier fires recorded since 2016: 8,514 ha in 2016, 252 ha in 2017, 5,187 ha in 2018, 1,701 ha in 2019, 8,271 ha in 2020, 7,154 ha in 2021, 1,592 ha in 2022, 11,280 ha in 2023, 1,660 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 17,471 ha that had burned before.
- 11,280 ha Oeiras fire, September 2023 13,580 ha in total; the hectares shown are those it shares with this fire
- 6,970 ha Oeiras fire, August 2020 10,621 ha in total; the hectares shown are those it shares with this fire
- 4,129 ha Colônia do Piauí fire, September 2018 11,378 ha in total; the hectares shown are those it shares with this fire
- 3,961 ha Oeiras fire, August 2016 4,301 ha in total; the hectares shown are those it shares with this fire
- 3,459 ha Oeiras fire, August 2016 3,694 ha in total; the hectares shown are those it shares with this fire
- 3,318 ha Oeiras fire, September 2021 3,506 ha in total; the hectares shown are those it shares with this fire
- 536 ha Oeiras fire, July 2021 3,188 ha in total; the hectares shown are those it shares with this fire
- 235 ha Colônia do Piauí fire, October 2025 3,670 ha in total; the hectares shown are those it shares with this fire
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
17,129 ha reached on 23 Aug6.3 %
-
Colônia do Piauí 6,994 inhabitants4,075 ha reached on 8 Sept4.3 %
Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance runs from the point marking the centre of each area to the nearest fire: staying a kilometre away does not mean it reached the houses.
People and buildings inside the perimeter
GHSL 2025Inside the perimeter there were about 4.0 hectares of built-up land and about 200 residents (GHSL 2025, satellite-based estimate).
This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned. The GHSL 2025 epoch is a projection made from 2020 and earlier data.
Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu
The weather day by day
ECMWF ERA5 reanalysis at the fire location, the standard reference for past weather, and the Canadian Fire Weather Index (the same system Copernicus uses), computed by WorldFires from that data. Days after the fire run until the first rain.
Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)
| Day | High | Min. humidity | Peak gust | Rain | Danger (FWI) |
|---|---|---|---|---|---|
| 16 Aug | 35.7 °C | 22 % | 48 km/h | 0.0 mm | Extreme 52 |
| 17 Aug | 35.3 °C | 22 % | 44 km/h | 0.0 mm | Extreme 52 |
| 18 Aug | 35.5 °C | 27 % | 44 km/h | 0.0 mm | Very high 49 |
| 19 Aug | 35.5 °C | 28 % | 42 km/h | 0.0 mm | Very high 47 |
| 20 Aug | 36.4 °C | 22 % | 40 km/h | 0.0 mm | Very high 47 |
| 21 Aug | 37.7 °C | 18 % | 37 km/h | 0.0 mm | Extreme 50 |
| 22 Aug | 38.5 °C | 15 % | 39 km/h | 0.0 mm | Extreme 54 |
| 23 Aug | 38.3 °C | 16 % | 38 km/h | 0.0 mm | Extreme 52 |
| 24 Aug | 38.0 °C | 16 % | 43 km/h | 0.0 mm | Extreme 57 |
| 25 Aug | 35.6 °C | 22 % | 47 km/h | 0.0 mm | Extreme 58 |
| 26 Aug | 36.8 °C | 21 % | 39 km/h | 0.0 mm | Extreme 54 |
| 27 Aug | 37.3 °C | 26 % | 29 km/h | 0.0 mm | Very high 44 |
| 28 Aug | 37.6 °C | 25 % | 33 km/h | 0.0 mm | Very high 48 |
| 29 Aug | 38.4 °C | 20 % | 38 km/h | 0.0 mm | Extreme 51 |
| 30 Aug | 38.0 °C | 23 % | 40 km/h | 0.0 mm | Extreme 52 |
| 31 Aug | 38.0 °C | 23 % | 37 km/h | 0.0 mm | Very high 49 |
| 1 Sept | 38.2 °C | 23 % | 35 km/h | 0.0 mm | Very high 50 |
| 2 Sept | 39.3 °C | 22 % | 30 km/h | 0.0 mm | Very high 45 |
| 3 Sept | 39.2 °C | 21 % | 27 km/h | 0.0 mm | Very high 46 |
| 4 Sept | 37.4 °C | 28 % | 32 km/h | 0.0 mm | Very high 46 |
| 5 Sept | 38.0 °C | 22 % | 16 km/h | 0.0 mm | Very high 39 |
| 6 Sept | 37.5 °C | 25 % | 26 km/h | 0.0 mm | Very high 43 |
| 7 Sept | 39.2 °C | 21 % | 26 km/h | 0.1 mm | Very high 44 |
| 8 Sept | 37.1 °C | 23 % | 42 km/h | 0.0 mm | Extreme 53 |
| 9 Sept | 37.2 °C | 14 % | 42 km/h | 0.0 mm | Extreme 58 |
| 10 Sept | 36.8 °C | 22 % | 43 km/h | 0.0 mm | Extreme 57 |
| 11 Sept | 37.1 °C | 20 % | 38 km/h | 0.0 mm | Extreme 54 |
| 12 Sept | 38.2 °C | 20 % | 40 km/h | 0.0 mm | Extreme 55 |
| 13 Sept | 39.2 °C | 19 % | 37 km/h | 0.0 mm | Extreme 52 |
| 14 Sept | 38.7 °C | 17 % | 42 km/h | 0.0 mm | Extreme 56 |
| 15 Sept | 38.4 °C | 17 % | 34 km/h | 0.0 mm | Extreme 52 |
| 16 Sept | 39.8 °C | 15 % | 35 km/h | 0.0 mm | Extreme 52 |
| 17 Sept | 37.2 °C | 22 % | 46 km/h | 0.0 mm | Extreme 59 |
| 18 Sept | 36.0 °C | 29 % | 45 km/h | 0.0 mm | Extreme 52 |
| 19 Sept | 36.7 °C | 22 % | 45 km/h | 0.0 mm | Extreme 53 |
| 20 Sept | 36.8 °C | 22 % | 44 km/h | 0.0 mm | Extreme 52 |
| 21 Sept | 38.5 °C | 19 % | 40 km/h | 0.0 mm | Extreme 51 |
| 22 Sept | 39.4 °C | 18 % | 36 km/h | 0.0 mm | Extreme 50 |
| 23 Sept | 38.7 °C | 23 % | 27 km/h | 0.0 mm | Very high 46 |
| 24 Sept | 39.9 °C | 22 % | 24 km/h | 0.0 mm | Very high 45 |
| 25 Sept | 38.2 °C | 26 % | 34 km/h | 0.0 mm | Very high 49 |
| 26 Sept | 37.9 °C | 25 % | 42 km/h | 0.0 mm | Extreme 56 |
| 27 Sept | 38.0 °C | 24 % | 46 km/h | 0.0 mm | Extreme 59 |
| 28 Sept | 37.7 °C | 26 % | 40 km/h | 0.0 mm | Extreme 54 |
| 29 Sept | 38.0 °C | 25 % | 39 km/h | 0.0 mm | Extreme 54 |
| 30 Sept after | 39.2 °C | 24 % | 39 km/h | 0.0 mm | Extreme 55 |
| 1 Oct after | 39.6 °C | 25 % | 36 km/h | 0.0 mm | Extreme 52 |
| 2 Oct after | 38.3 °C | 26 % | 25 km/h | 0.0 mm | Very high 45 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.
The smoke
CAMS · CopernicusOn 15 September 2026 the air beside the fire reached 22 µg/m³ of PM2.5, but no daily average passed the WHO guideline (15).
Particles from the Copernicus CAMS model at the centre of the perimeter; these are not measurements in each town. The pale bar is the worst hour, the solid one the daily average.
Open-Meteo.com (CC BY 4.0) · Copernicus Atmosphere Monitoring Service (CAMS)
Detections table · 778Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
Frequently asked questions
- How long did the Oeiras fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 23 August 2026 to 29 September 2026 (38 days). The perimeter dates it from 23 August 2026 to 28 September 2026.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 21,063 hectares (210.6 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire entered 2 municipalities: Oeiras (17,129 ha, 6.3 %); Colônia do Piauí (4,075 ha, 4.3 %).
- Is the Oeiras fire still active?
- No fire detections since 29 Sept 2026, 15:48 UTC. A lack of detections is not an official extinction.
- What was the weather like?
- During the fire the temperature reached 39.9 °C, humidity dropped to 14 % and gusts hit 48 km/h. The fire danger index (FWI) reached 59, class Extreme.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Brazil (geoBoundaries). It is not an official report.
Where to verify it
A satellite detection is not an official report. Final figures and the fire’s status are published by each country’s emergency service.
Emergency number: 193 · Emergency number and official warnings ›
Satellite cross-check
History of this page Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
No changes since 24 October 2026.
Does something look wrong on this page?
This page is built from satellite data and official records, and it sometimes gets things wrong: the wrong dates, the wrong town, two fires merged into one, or something that was not a wildfire at all. If you know this fire first-hand (you live nearby, saw it, fought it or reported on it), tell us what really happened and we will check it.
Report an error
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 2 polygons grouped in this page.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 23 August 2026 to 28 September 2026. 778 Suomi-NPP VIIRS detections on those dates.
- We have not matched this page with any official record.
- Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.
- Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2025, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.
Where this data comes from
The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. Municipal boundaries come from geoBoundaries ADM2 (Creative Commons Attribution 3.0 Intergovernmental Organisations (CC BY 3.0 IGO)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.