How long did the Aroazes fire last?

GWIS (Copernicus) dates it between 24 October 2025 and 31 October 2025: 8 days between the first and last heat detection of the perimeter.

How much area did it burn?

The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,672 hectares (36.7 km²). It is an estimate: official national figures may differ.

Which municipalities burned?

The fire entered 2 municipalities: Valença do Piauí (2,644 ha, 2.0 %); Aroazes (1,052 ha, 1.3 %).

What was the weather like?

During the fire the temperature reached 39.4 °C, humidity dropped to 19 % and gusts hit 49 km/h. The fire danger index (FWI) reached 53, 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.

BR · Brazil · 2025-10-24 → 2025-10-31

Aroazes fire, October 2025 Valença do Piauí, Aroazes

Out · last detection 31 Oct 2025, 16:23 UTC

The fire started on 24 October 2025 in Aroazes, Brazil, and satellites saw it burning for 8 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,672 hectares from heat detections, spread across 2 municipalities.

It is the 579th largest in Piaui since 2016 (of 803 with a page). Number 531 in Brazil in 2025, of 714.

Burnt area: 3,672ha; GWIS perimeter (Copernicus)
Duration: 8days; 24 Oct 2025 – 31 Oct 2025
Municipalities hit: 2; municipalities
Started on: 24 Oct; 2025
Heat detections: 117; in a single hotspot: 53 MW
Danger at start: 44; Very high · FWI index
Energy released: 1.1GW; sum of detected power

Play back 31 Oct 2025

HOTSPOTS BY DAY 24 Oct31 Oct

How it evolved, day by day

25262728293031

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

The weather it burned in

39°high

49km/h · peak gust

19%lowest humidity

It had gone 2 days without rain (1 mm or more) when it started.

This area had burned before

45% of the perimeter overlaps earlier fires recorded since 2016: 957 ha in 2016, 1,583 ha in 2021, 279 ha in 2023, 89 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 1,658 ha that had burned before.

1,545 ha Valença do Piauí fire, September 2021 3,559 ha in total; the hectares shown are those it shares with this fire

What happened to each town

Valença do Piauí 22,279 inhabitants

2,644 ha reached on 25 Oct

2.0 %
Aroazes 5,369 inhabitants where it started

1,052 ha reached on 25 Oct

1.3 %

Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance is from the town centre to the nearest fire: staying a kilometre away does not mean it reached the houses.

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)
24 Oct	36.6 °C	24 %	49 km/h	0.0 mm	Very high 44
25 Oct	37.2 °C	20 %	47 km/h	0.0 mm	Very high 47
26 Oct	37.5 °C	19 %	48 km/h	0.0 mm	Very high 50
27 Oct	38.3 °C	19 %	43 km/h	0.0 mm	Very high 47
28 Oct	37.7 °C	19 %	47 km/h	0.0 mm	Very high 50
29 Oct	37.8 °C	21 %	49 km/h	0.0 mm	Extreme 53
30 Oct	38.9 °C	19 %	38 km/h	0.0 mm	Very high 47
31 Oct	37.0 °C	30 %	32 km/h	0.0 mm	Very high 42
1 Nov after	36.5 °C	34 %	30 km/h	0.1 mm	High 37
2 Nov after	36.7 °C	29 %	32 km/h	0.0 mm	Very high 39
3 Nov after	37.6 °C	26 %	38 km/h	0.0 mm	Very high 44
4 Nov after	39.4 °C	20 %	28 km/h	0.0 mm	Very high 42
5 Nov after	39.1 °C	24 %	34 km/h	0.0 mm	Very high 44
6 Nov after	36.6 °C	29 %	31 km/h	0.0 mm	Very high 40
7 Nov after	38.4 °C	22 %	25 km/h	0.0 mm	High 37
8 Nov after	36.4 °C	32 %	26 km/h	0.0 mm	High 38
9 Nov after	37.7 °C	26 %	33 km/h	0.0 mm	Very high 39
10 Nov after	38.5 °C	24 %	38 km/h	0.0 mm	Very high 45
11 Nov after	37.8 °C	22 %	37 km/h	0.0 mm	Very high 42
12 Nov after	37.9 °C	18 %	35 km/h	0.0 mm	Very high 46
13 Nov after	37.9 °C	17 %	38 km/h	0.0 mm	Very high 48
14 Nov after	37.8 °C	19 %	50 km/h	0.0 mm	Extreme 58
15 Nov after	38.0 °C	20 %	47 km/h	0.0 mm	Extreme 54

Before and after, from space

Drag the line to compare the same ground before the fire and after it.

↔

Before · 17 Oct 2025

After · 7 Nov 2025

Before After

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 · Copernicus

On 1 November 2025 the air beside the fire reached 18 µg/m³ of PM2.5, but no daily average passed the WHO guideline (15).

PM2.5 peak18 µg/m³

Days over the guideline0 days

PM1019 µg/m³

Optical depth0.44

WHO 15

22232425262728293031123

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 · 117Every 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

All fires in Brazil ›

Frequently asked questions

How long did the Aroazes fire last?: GWIS (Copernicus) dates it between 24 October 2025 and 31 October 2025: 8 days between the first and last heat detection of the perimeter.
How much area did it burn?: The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,672 hectares (36.7 km²). It is an estimate: official national figures may differ.
Which municipalities burned?: The fire entered 2 municipalities: Valença do Piauí (2,644 ha, 2.0 %); Aroazes (1,052 ha, 1.3 %).
What was the weather like?: During the fire the temperature reached 39.4 °C, humidity dropped to 19 % and gusts hit 49 km/h. The fire danger index (FWI) reached 53, 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

INPE · Programa Queimadas ↗
IBAMA · Prevfogo ↗

Satellite cross-check

NASA FIRMS ↗
GWIS · Copernicus ↗

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

What do you think is wrong?

Dates or duration Place or towns Burned area Name It was not a wildfire Same fire as another page Something else

What really happened?

Your connection to the fire (optional) Email (optional)

We will only use your email to reply about this report. Privacy. This is not an emergency service: if there is a fire now, call 193.

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.

Where it burned