Burned area
satellite only3,464ha
Perimeter published by GWIS (Copernicus).
- Source
- GWIS (Copernicus)
- Date
- 26 Sept 2026 – 6 Oct 2026
+− cross-check
No official record is matched to this page to compare it with.
BR · Brazil · –
Nazaré do Piauí fire, September 2026 Nazaré do Piauí, Floriano
Out · last detection 6 Oct 2026, 17:15 UTC
The fire started on 26 September 2026 in Nazaré do Piauí, Brazil, and satellites saw it burning for 11 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,464 hectares from heat detections, spread across 2 municipalities.
Number 645 in Brazil in 2026, of 797.
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…
Use this data
Fire page data · version 2026-10-24matches 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 only11days
26 Sept 2026 to 6 Oct 2026: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 6 Oct 2026, 17:15 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 only26 Sept 2026
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 26 Sept 2026
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only63
VIIRS detections at 375 m. Most intense hotspot: 102 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 26 Sept 2026 – 6 Oct 2026
+− 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 only420MW
Total radiative power on 27 September 2026; hotspots that day: 15.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 27 Sept 2026
+− 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
model42.4FWI · very high
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 60.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 26 Sept 2026, 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
model38.1°C · 28% RH
High of 38.1 °C and minimum humidity of 28% on 30 September 2026; gusts of 42 km/h on 27 September 2026.
- Source
- weather model at the fire’s grid cell
- Date
- 26 Sept 2026 – 6 Oct 2026
- 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
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
· reconstructed GHSLPopulation and built-up area computed
What was saved on 24 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
- 3,464 ha
- Dates
- 26 Sept 2026 – 6 Oct 2026
- Name
- Nazaré do Piauí
- Official record
- —
Versioned permanent link
https://worldfires.org/en/fire/nazare-do-piaui-2026-09?v=2026-10-24A 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 nazare-do-piaui-2026-09.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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026-09-26 | 4 | 24 | 37 | 27.6 | 28 | 13.5 | 33.8 | 0 | 42.4 | muy_alto | 1 |
| 2026-09-27 | 15 | 420 | 37.7 | 27.7 | 22 | 19.2 | 42.1 | 0 | 49 | muy_alto | 1 |
| 2026-09-28 | 20 | 168 | 37.4 | 27.1 | 27 | 18 | 40.7 | 0 | 44.9 | muy_alto | 1 |
| 2026-09-29 | 6 | 155 | 37.5 | 27.7 | 27 | 9.7 | 24.1 | 0 | 42.1 | muy_alto | 1 |
| 2026-09-30 | 7 | 38 | 38.1 | 28.4 | 28 | 12.9 | 31.7 | 0 | 46 | muy_alto | 1 |
| 2026-10-01 | 7 | 134 | 38 | 28 | 29 | 14.4 | 32.4 | 0 | 45.3 | muy_alto | 1 |
| 2026-10-02 | 0 | 0 | 36.2 | 27.6 | 35 | 13.6 | 30.6 | 0.1 | 42.3 | muy_alto | 1 |
| 2026-10-03 | 0 | 0 | 34.5 | 26 | 44 | 12.1 | 24.1 | 0.8 | 22 | alto | 1 |
| 2026-10-04 | 1 | 3 | 37.6 | 25.4 | 25 | 18.4 | 38.9 | 0 | 44.9 | muy_alto | 1 |
| 2026-10-05 | 0 | 0 | 37.1 | 25.8 | 20 | 17.4 | 40.7 | 0 | 53.3 | extremo | 1 |
| 2026-10-06 | 3 | 42 | 37.3 | 24.1 | 24 | 18.4 | 41.4 | 0 | 56.5 | extremo | 1 |
| 2026-10-07 | 0 | 0 | 37.8 | 28.2 | 19 | 20.8 | 44.6 | 0 | 57.3 | extremo | 0 |
| 2026-10-08 | 0 | 0 | 38.8 | 25 | 20 | 20.9 | 44.6 | 0 | 57.7 | extremo | 0 |
| 2026-10-09 | 0 | 0 | 38.2 | 25.9 | 21 | 16.9 | 37.1 | 0 | 50.3 | extremo | 0 |
| 2026-10-10 | 0 | 0 | 38.1 | 26.7 | 24 | 10.7 | 28.1 | 0 | 46.5 | muy_alto | 0 |
| 2026-10-11 | 0 | 0 | 37.9 | 25 | 20 | 10.2 | 29.2 | 0 | 46.5 | muy_alto | 0 |
| 2026-10-12 | 0 | 0 | 37.8 | 24.7 | 24 | 11.6 | 32.4 | 0 | 49.8 | muy_alto | 0 |
| 2026-10-13 | 0 | 0 | 38.2 | 24.4 | 23 | 16.6 | 37.1 | 0 | 51.4 | extremo | 0 |
| 2026-10-14 | 0 | 0 | 38.3 | 23.7 | 25 | 10.8 | 28.1 | 0 | 50.3 | extremo | 0 |
| 2026-10-15 | 0 | 0 | 38 | 25.3 | 25 | 16 | 29.5 | 0 | 51.1 | extremo | 0 |
| 2026-10-16 | 0 | 0 | 37.8 | 26.1 | 31 | 14.6 | 23.8 | 0 | 36.9 | 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
- 3,464ha
- GWIS perimeter (Copernicus)
- Duration
- 11days
- 26 Sept 2026 – 6 Oct 2026
- Municipalities hit
- 2
- municipalities
- Started on
- 26 Sept
- 2026
- Heat detections
- 63
- in a single hotspot: 102 MW
- Danger at start
- 42
- Very high · FWI index
- Average daily power
- 123MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
26 Sept6 Oct
6 Oct 2026
How it evolved, day by day
27 Sept
30 Sept
2 Oct
5 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
42km/h · peak gust
20%lowest humidity
It had gone more than two months without rain (1 mm or more) when it started.
This area had burned before
97% of the perimeter overlaps earlier fires recorded since 2016: 1,566 ha in 2016, 2,546 ha in 2018, 1,731 ha in 2019, 983 ha in 2021, 159 ha in 2023, 2,970 ha in 2024, 168 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 3,349 ha that had burned before.
- 2,544 ha Nazaré do Piauí fire, September 2018 5,197 ha in total; the hectares shown are those it shares with this fire
- 2,338 ha Nazaré do Piauí fire, September 2024 4,939 ha in total; the hectares shown are those it shares with this fire
- 1,731 ha Floriano fire, September 2019 10,320 ha in total; the hectares shown are those it shares with this fire
- 756 ha Floriano fire, July 2021 6,518 ha in total; the hectares shown are those it shares with this fire
- 137 ha Floriano fire, June 2016 16,292 ha in total; the hectares shown are those it shares with this fire
- 2 ha Nazaré do Piauí fire, July 2018 4,417 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
-
3,469 ha reached on 26 Sept2.6 %
-
Floriano 62,036 inhabitants17 ha0.0 %
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 area0.10 ha
Residents< 20
Inside the perimeter there were about 0.10 hectares of 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)
Started with 60 days without rain: 55 % of the area in Brazil
| Day | High | Min. humidity | Peak gust | Rain | Danger (FWI) |
|---|---|---|---|---|---|
| 26 Sept | 37.0 °C | 28 % | 34 km/h | 0.0 mm | Very high 42 |
| 27 Sept | 37.7 °C | 22 % | 42 km/h | 0.0 mm | Very high 49 |
| 28 Sept | 37.4 °C | 27 % | 41 km/h | 0.0 mm | Very high 45 |
| 29 Sept | 37.5 °C | 27 % | 24 km/h | 0.0 mm | Very high 42 |
| 30 Sept | 38.1 °C | 28 % | 32 km/h | 0.0 mm | Very high 46 |
| 1 Oct | 38.0 °C | 29 % | 32 km/h | 0.0 mm | Very high 45 |
| 2 Oct | 36.2 °C | 35 % | 31 km/h | 0.1 mm | Very high 42 |
| 3 Oct | 34.5 °C | 44 % | 24 km/h | 0.8 mm | High 22 |
| 4 Oct | 37.6 °C | 25 % | 39 km/h | 0.0 mm | Very high 45 |
| 5 Oct | 37.1 °C | 20 % | 41 km/h | 0.0 mm | Extreme 53 |
| 6 Oct | 37.3 °C | 24 % | 41 km/h | 0.0 mm | Extreme 56 |
| 7 Oct after | 37.8 °C | 19 % | 45 km/h | 0.0 mm | Extreme 57 |
| 8 Oct after | 38.8 °C | 20 % | 45 km/h | 0.0 mm | Extreme 58 |
| 9 Oct after | 38.2 °C | 21 % | 37 km/h | 0.0 mm | Extreme 50 |
| 10 Oct after | 38.1 °C | 24 % | 28 km/h | 0.0 mm | Very high 46 |
| 11 Oct after | 37.9 °C | 20 % | 29 km/h | 0.0 mm | Very high 46 |
| 12 Oct after | 37.8 °C | 24 % | 32 km/h | 0.0 mm | Very high 50 |
| 13 Oct after | 38.2 °C | 23 % | 37 km/h | 0.0 mm | Extreme 51 |
| 14 Oct after | 38.3 °C | 25 % | 28 km/h | 0.0 mm | Extreme 50 |
| 15 Oct after | 38.0 °C | 25 % | 30 km/h | 0.0 mm | Extreme 51 |
| 16 Oct after | 37.8 °C | 31 % | 24 km/h | 0.0 mm | High 37 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 19 Sept 2026
After · 13 Oct 2026
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 3 October 2026 the air beside the fire reached 30 µg/m³ of PM2.5. That day averaged 17: 1.2 times the WHO daily guideline (15).
PM2.5 peak30 µg/m³
Days over the guideline1 day
PM1032 µg/m³
Optical depth0.49
WHO 15
24 Sept27 Sept30 Sept3 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 · 63Every 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
- 16,292 haFlorianoJune 2016 · 35 days · 12 km away
- 14,508 haNazaré do PiauíAugust 2026 · 18 days · 14 km away
- 18,305 haNazaré do PiauíSeptember 2019 · 20 days · 15 km away
- 36,039 haNazaré do Piauí4 September 2018 · 41 days · 38 km away
- 14,770 haAmaranteSeptember 2025 · 26 days · 40 km away
- 14,264 haFrancisco AyresSeptember 2021 · 23 days · 40 km away
Frequently asked questions
- How long did the Nazaré do Piauí fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 26 September 2026 to 6 October 2026 (11 days). The perimeter dates it from 26 September 2026 to 5 October 2026.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,464 hectares (34.6 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire entered 2 municipalities: Nazaré do Piauí (3,469 ha, 2.6 %); Floriano (17 ha, 0.0 %).
- What was the weather like?
- During the fire the temperature reached 38.1 °C, humidity dropped to 20 % and gusts hit 42 km/h. The fire danger index (FWI) reached 56, 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.
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 26 September 2026 to 5 October 2026. 63 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.