Burned area
satellite only19,217ha
Perimeter published by GWIS (Copernicus).
- Source
- GWIS (Copernicus)
- Date
- 4 Oct 2025 – 12 Oct 2025
+− cross-check
No official record is matched to this page to compare it with.
BR · Brazil · –
Balsas fire, 4 October 2025 Balsas
Out · last detection 11 Oct 2025, 15:57 UTC
The fire started on 4 October 2025 in Balsas, Brazil, and satellites saw it burning for 9 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 19,217 hectares from heat detections, spread across a single municipality.
Number 4 in Brazil in 2025, of 188.
GWIS near-real-time perimeter, from the layer that changed in October 2025: this fire is not compared with fires from earlier years, because since then the GWIS layer gives more and larger perimeters.
Use this data
Compare with…
Suggestions: Balsas · 2022Balsas · 2017Balsas · 2024Balsas · 2017
Use this data
Fire page data · version 2026-10-25matches the official recordwith caveatssatellite onlymodel
When copying, the sentence is
Tick the figures you want: they make up the lede and the CSV.
Duration by satellite
satellite only9days
4 Oct 2025 to 12 Oct 2025: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 11 Oct 2025, 15:57 UTC
+− cross-check
Satellites pass a few times a day and cloud or smoke can hide the fire: a lack of detections is not an official extinction. Each country’s emergency service declares a fire contained or out.
Start
satellite only4 Oct 2025
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 4 Oct 2025
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only449
VIIRS detections at 375 m. Most intense hotspot: 232 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 4 Oct 2025 – 12 Oct 2025
+− cross-check
There is no official record to compare with. Each hotspot is a pixel detected in one satellite pass, not a separate fire.
The worst day
satellite only3,252MW
Total radiative power on 5 October 2025; hotspots that day: 206.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 5 Oct 2025
+− cross-check
Fire radiative power (FRP) measures the energy the fire gives off when the satellite passes. Added up by day, it compares intensity, not area.
Danger at the start
model51.7FWI · extreme
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 11.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 4 Oct 2025, local noon
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings
Weather during the fire
model37.6°C · 28% RH
High of 37.6 °C and minimum humidity of 28% on 6 October 2025; gusts of 49 km/h on 4 October 2025.
- Source
- weather model at the fire’s grid cell
- Date
- 4 Oct 2025 – 12 Oct 2025
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
This page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
-
logLast day with fire: 9 October 2025 → 12 October 2025.
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
· reconstructed GHSLPopulation and built-up area computed
What was saved on 25 October 2026
Every night a snapshot of what the page shows is saved. If anything changes, it appears in the list as a log entry.
- Area
- 19,217 ha
- Dates
- 4 Oct 2025 – 12 Oct 2025
- Name
- Balsas
- Official record
- —
Versioned permanent link
https://worldfires.org/en/fire/balsas-2025-10-3?v=2026-10-25A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire balsas-2025-10-3.csv · daily, no individual hotspots
| fecha | focos_viirs | frp_mw | tmax_c | tmin_c | hr_min_pct | viento_max_kmh | racha_max_kmh | precip_mm | fwi | clase_fwi | dentro_del_incendio |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025-10-04 | 32 | 2,067 | 36 | 24.4 | 21 | 22.3 | 48.6 | 0 | 51.7 | extremo | 1 |
| 2025-10-05 | 206 | 3,252 | 36.4 | 24.4 | 22 | 20.7 | 45.7 | 0 | 50.3 | extremo | 1 |
| 2025-10-06 | 73 | 522 | 37.6 | 25 | 28 | 16.4 | 36.4 | 0 | 45.1 | muy_alto | 1 |
| 2025-10-07 | 43 | 409 | 37.3 | 24.9 | 25 | 13.5 | 35.3 | 0 | 42.5 | muy_alto | 1 |
| 2025-10-08 | 47 | 748 | 37.5 | 24.2 | 24 | 15.1 | 36.7 | 0 | 44.5 | muy_alto | 1 |
| 2025-10-09 | 40 | 841 | 34.4 | 24.9 | 34 | 11.5 | 24.8 | 0.1 | 35.6 | alto | 1 |
| 2025-10-10 | 5 | 24 | 37 | 23.7 | 26 | 16.4 | 37.1 | 0 | 40.7 | muy_alto | 1 |
| 2025-10-11 | 3 | 47 | 35.6 | 25 | 26 | 16.3 | 35.6 | 0 | 40.9 | muy_alto | 1 |
| 2025-10-12 | 0 | 0 | 31.2 | 24 | 45 | 18.5 | 38.2 | 0 | 34 | alto | 1 |
| 2025-10-13 | 0 | 0 | 36.6 | 22.2 | 26 | 16.3 | 39.6 | 0 | 40.1 | muy_alto | 0 |
| 2025-10-14 | 0 | 0 | 31.8 | 24.8 | 47 | 14.7 | 31.3 | 1 | 22.1 | alto | 0 |
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: GWIS (Copernicus), NASA FIRMS (VIIRS), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0), GHSL (JRC). Open-Meteo.com · How we build fire pages: methodology
- Burnt area
- 19,217ha
- GWIS perimeter (Copernicus)
- Duration
- 9days
- 4 Oct 2025 – 12 Oct 2025
- Municipalities hit
- 1
- municipalities
- Started on
- 4 Oct
- 2025
- Heat detections
- 449
- in a single hotspot: 232 MW
- Danger at start
- 52
- Extreme · FWI index
- Average daily power
- 989MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
4 Oct12 Oct
11 Oct 2025
How it evolved, day by day
5 Oct
8 Oct
10 Oct
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
38°high
49km/h · peak gust
21%lowest humidity
It had gone 11 days without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 14 Oct.
This area had burned before
61% of the perimeter overlaps earlier fires recorded since 2016: 3,656 ha in 2017, 210 ha in 2018, 27 ha in 2019, 138 ha in 2020, 448 ha in 2021, 10,726 ha in 2022, 376 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 11,733 ha that had burned before.
- 9,075 ha Balsas fire, July 2022 17,385 ha in total; the hectares shown are those it shares with this fire
- 3,488 ha Balsas fire, October 2017 3,954 ha in total; the hectares shown are those it shares with this fire
- 376 ha Balsas fire, August 2024 10,204 ha in total; the hectares shown are those it shares with this fire
- 168 ha Balsas fire, October 2017 4,812 ha in total; the hectares shown are those it shares with this fire
- 18 ha Balsas fire, September 2022 17,378 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
-
19,355 ha reached on 4 Oct1.5 %
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 2025Built-up area< 0.1 ha
Residents< 20
Inside the perimeter there was no noticeable built-up land and almost nobody lived there (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) |
|---|---|---|---|---|---|
| 4 Oct | 36.0 °C | 21 % | 49 km/h | 0.0 mm | Extreme 52 |
| 5 Oct | 36.4 °C | 22 % | 46 km/h | 0.0 mm | Extreme 50 |
| 6 Oct | 37.6 °C | 28 % | 36 km/h | 0.0 mm | Very high 45 |
| 7 Oct | 37.3 °C | 25 % | 35 km/h | 0.0 mm | Very high 42 |
| 8 Oct | 37.5 °C | 24 % | 37 km/h | 0.0 mm | Very high 44 |
| 9 Oct | 34.4 °C | 34 % | 25 km/h | 0.1 mm | High 36 |
| 10 Oct | 37.0 °C | 26 % | 37 km/h | 0.0 mm | Very high 41 |
| 11 Oct | 35.6 °C | 26 % | 36 km/h | 0.0 mm | Very high 41 |
| 12 Oct | 31.2 °C | 45 % | 38 km/h | 0.0 mm | High 34 |
| 13 Oct after | 36.6 °C | 26 % | 40 km/h | 0.0 mm | Very high 40 |
| 14 Oct after | 31.8 °C | 47 % | 31 km/h | 1.0 mm | High 22 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 27 Sept 2025
After · 19 Oct 2025
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
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 8 October 2025 the air beside the fire reached 36 µg/m³ of PM2.5. That day averaged 19: 1.3 times the WHO daily guideline (15).
PM2.5 peak36 µg/m³
Days over the guideline4 days
PM1037 µg/m³
Optical depth0.49
WHO 15
26 Sept30 Sept4 Oct8 Oct12 Oct
Good
Fair
Moderate
Poor
Very poor
Extremely poor
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 · 449Every satellite heat detection, one by one, with time, satellite, power and coordinates.
⬇ Download CSV
Times in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
Frequently asked questions
- How long did the Balsas fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 4 October 2025 to 12 October 2025 (9 days). The perimeter dates it from 4 October 2025 to 9 October 2025.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 19,217 hectares (192.2 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Balsas (19,355 ha, 1.5 %).
- What was the weather like?
- During the fire the temperature reached 37.6 °C, humidity dropped to 21 % and gusts hit 49 km/h. The fire danger index (FWI) reached 52, 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 · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
- Last day with fire: 9 October 2025 → 12 October 2025.
RSS Changes to this page With cross-checks and a citable version
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.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 4 October 2025 to 9 October 2025. 449 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.