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Nazaré do Piauí fire, 4 September 2018 São José do Peixe, Flores do Piauí, São Francisco do Piauí

Out · last detection 14 Oct 2018, 15:41 UTC

The fire started on 4 September 2018 in Nazaré do Piauí, Brazil, and satellites saw it burning for 41 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 36,039 hectares from heat detections, spread across 5 municipalities.

It is the 6th largest in Piaui since 2016 (of 665 with a page). Number 2 in Brazil in 2018, of 291.

Compare with…

Suggestions: Pedro Laurentino · 2018Floriano · 2019Flores do Piauí · 2020São José do Peixe · 2021

Burnt area
36,039ha
GWIS perimeter (Copernicus)
Duration
41days
4 Sept 2018 – 14 Oct 2018
Municipalities hit
5
municipalities
Started on
4 Sept
2018
Heat detections
1,744
in a single hotspot: 118 MW
Danger at start
46
Very high · FWI index
Average daily power
431MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 4 Sept14 Oct
14 Oct 2018

How it evolved, day by day

4 Sept 2018 · 103 MW · 10 5 Sept 2018 · 15 MW · 3 8 Sept 2018 · 8 MW · 7 9 Sept 2018 · 869 MW · 55 10 Sept 2018 · 1,639 MW · 142 11 Sept 2018 · 198 MW · 35 12 Sept 2018 · 469 MW · 77 13 Sept 2018 · 625 MW · 106 14 Sept 2018 · 757 MW · 162 15 Sept 2018 · 571 MW · 78 16 Sept 2018 · 804 MW · 65 17 Sept 2018 · 11 MW · 9 18 Sept 2018 · 715 MW · 82 19 Sept 2018 · 345 MW · 88 20 Sept 2018 · 505 MW · 42 21 Sept 2018 · 293 MW · 39 22 Sept 2018 · 310 MW · 38 23 Sept 2018 · 1,969 MW · 91 24 Sept 2018 · 419 MW · 60 25 Sept 2018 · 119 MW · 25 26 Sept 2018 · 36 MW · 4 27 Sept 2018 · 118 MW · 18 28 Sept 2018 · 224 MW · 43 29 Sept 2018 · 647 MW · 102 30 Sept 2018 · 497 MW · 58 1 Oct 2018 · 207 MW · 19 2 Oct 2018 · 329 MW · 28 3 Oct 2018 · 382 MW · 55 4 Oct 2018 · 966 MW · 30 5 Oct 2018 · 211 MW · 24 8 Oct 2018 · 80 MW · 6 9 Oct 2018 · 563 MW · 41 10 Oct 2018 · 292 MW · 33 11 Oct 2018 · 168 MW · 23 12 Oct 2018 · 233 MW · 25 13 Oct 2018 · 79 MW · 12 14 Oct 2018 · 156 MW · 9
4 Sept 14 Sept 23 Sept 30 Sept 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

40°high
49km/h · peak gust
21%lowest humidity

It had gone more than two months without rain (1 mm or more) when it started. Rain came after the fire: 6.2 mm on 16 Oct.

This area had burned before

7% of the perimeter overlaps earlier fires recorded since 2016: 2,003 ha in 2016, 515 ha in 2017.

How big is it?

10 km
It burned the equivalent of 23% of the area of London (360 km² against 1,583 km²).

London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).

This compares size, not location: both shapes are at the same scale, north up, centred on each other.

What happened to each town

  1. São José do Peixe 3,297 inhabitants
    20,317 ha reached on 4 Sept
    16 %
  2. Flores do Piauí 4,414 inhabitants
    10,351 ha reached on 12 Sept
    11 %
  3. São Francisco do Piauí 5,392 inhabitants
    2,735 ha reached on 13 Sept
    2.0 %
  4. Nazaré do Piauí 6,665 inhabitants where it started
    2,592 ha reached on 4 Sept
    2.0 %
  5. Ribeira do Piauí 4,055 inhabitants
    463 ha reached on 5 Oct
    0.4 %

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 2020
Built-up area0.44 ha
Residents≈ 30

Inside the perimeter there were about 0.44 hectares of built-up land and about 30 residents (GHSL 2020, 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.

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)
4 Sept 39.0 °C 28 % 35 km/h 0.0 mm Very high 46
5 Sept 36.6 °C 40 % 33 km/h 0.3 mm High 38
6 Sept 33.3 °C 39 % 28 km/h 1.1 mm High 23
7 Sept 36.1 °C 27 % 49 km/h 0.0 mm Extreme 58
8 Sept 35.1 °C 32 % 48 km/h 0.0 mm Extreme 57
9 Sept 36.0 °C 26 % 49 km/h 0.0 mm Extreme 56
10 Sept 36.5 °C 29 % 45 km/h 0.0 mm Extreme 54
11 Sept 37.1 °C 29 % 44 km/h 0.0 mm Extreme 55
12 Sept 37.8 °C 25 % 47 km/h 0.0 mm Extreme 59
13 Sept 36.1 °C 22 % 49 km/h 0.0 mm Extreme 70
14 Sept 36.4 °C 26 % 47 km/h 0.0 mm Extreme 65
15 Sept 36.8 °C 26 % 44 km/h 0.0 mm Extreme 59
16 Sept 37.8 °C 26 % 41 km/h 0.0 mm Extreme 56
17 Sept 39.1 °C 25 % 35 km/h 0.0 mm Extreme 55
18 Sept 39.7 °C 21 % 37 km/h 0.0 mm Extreme 64
19 Sept 38.5 °C 25 % 40 km/h 0.0 mm Extreme 62
20 Sept 37.4 °C 25 % 44 km/h 0.0 mm Extreme 65
21 Sept 37.3 °C 24 % 47 km/h 0.0 mm Extreme 64
22 Sept 37.9 °C 23 % 42 km/h 0.0 mm Extreme 55
23 Sept 38.1 °C 26 % 41 km/h 0.0 mm Extreme 55
24 Sept 37.2 °C 31 % 42 km/h 0.0 mm Extreme 55
25 Sept 36.5 °C 32 % 41 km/h 0.0 mm Extreme 55
26 Sept 37.9 °C 30 % 46 km/h 0.0 mm Extreme 57
27 Sept 38.0 °C 27 % 44 km/h 0.0 mm Extreme 58
28 Sept 39.1 °C 24 % 39 km/h 0.0 mm Extreme 54
29 Sept 39.2 °C 25 % 37 km/h 0.0 mm Very high 48
30 Sept 38.0 °C 27 % 30 km/h 0.0 mm Very high 49
1 Oct 37.8 °C 27 % 40 km/h 0.0 mm Extreme 51
2 Oct 38.1 °C 26 % 45 km/h 0.0 mm Extreme 53
3 Oct 38.8 °C 25 % 42 km/h 0.0 mm Very high 49
4 Oct 39.0 °C 28 % 28 km/h 0.0 mm Very high 45
5 Oct 37.8 °C 36 % 28 km/h 0.2 mm High 36
6 Oct 37.3 °C 31 % 32 km/h 0.0 mm Very high 42
7 Oct 37.3 °C 31 % 45 km/h 0.6 mm Very high 49
8 Oct 37.9 °C 27 % 45 km/h 0.0 mm Extreme 51
9 Oct 38.7 °C 22 % 44 km/h 0.0 mm Extreme 56
10 Oct 39.0 °C 21 % 44 km/h 0.0 mm Extreme 58
11 Oct 38.5 °C 28 % 44 km/h 0.0 mm Extreme 50
12 Oct 37.6 °C 31 % 44 km/h 0.0 mm Extreme 53
13 Oct 38.4 °C 27 % 40 km/h 0.0 mm Extreme 52
14 Oct 38.9 °C 30 % 25 km/h 0.2 mm Very high 44
15 Oct after 35.8 °C 43 % 30 km/h 0.3 mm High 32
16 Oct after 34.3 °C 47 % 27 km/h 6.2 mm Low 9

Its twins: fires that started in the same weather

It started with an FWI of 46.0, a minimum humidity of 28% and more than two months without rain. Fires in the area that started in weather like this since 2016: 29.

FWI at the start 46.0
Minimum humidity 28 %
Days without rain 60+
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Pedro Laurentino fire, August 2018
4,695 ha 16 days FWI 46.7 Min. humidity 29 % 97 km away, in 2018

First rain (1 mm or more) after it ended: none in the following ten days.

See its page Compare with this fire

What happened to them

15 days
median duration
4,800 ha
median area
10 %
went past 10,000 ha
3.1 mm
rain at the end (median; 13 of 29 had it)

It was 7.5 times larger than the median of its twins and lasted 41 days, against 15 days.

None of its 29 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 16 of 29, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.1 mm.

This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it

How it ended

6.2 mmfirst rain
16 Oct2 days after it ended
49km/h · max. gust

It was considered over on 14 Oct, and on 16 Oct 6.2 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 13 of 29, with a median of 3.1 mm.

Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

How a twin is chosen

  • Same area: fires that have already ended, less than 250 km from this one, since 2016.
  • Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
  • Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
  • Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
  • They are sorted by similarity, and the outlines of the first five are drawn.

How we calculate it

Before and after, from space

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

Before · 28 Aug 2018
After · 21 Oct 2018

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

Detections table · 1,744Every 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 timeSatelliteFRP (MW)LatLon

Other fires nearby

All fires in Brazil

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 4 September 2018 to 14 October 2018 (41 days). The perimeter dates it from 8 September 2018 to 14 October 2018.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 36,039 hectares (360.4 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 5 municipalities: São José do Peixe (20,317 ha, 16 %); Flores do Piauí (10,351 ha, 11 %); São Francisco do Piauí (2,735 ha, 2.0 %); Nazaré do Piauí (2,592 ha, 2.0 %); Ribeira do Piauí (463 ha, 0.4 %).
What was the weather like?
During the fire the temperature reached 39.7 °C, humidity dropped to 21 % and gusts hit 49 km/h. The fire danger index (FWI) reached 70, 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.
How did the fires that started in similar weather in this area end?
Fires less than 250 km away that started since 2016 with a similar FWI, humidity and dry spell: 29. Their median duration was 15 days and their median area 4,800 ha; 10 % went past 10,000 ha. None of its 29 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 16 of 29, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.1 mm.

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.
  1. Start date: 8 September 2018 → 4 September 2018.

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
What do you think is wrong?

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.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 4 polygons grouped in this page.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 8 September 2018 to 14 October 2018. 1,744 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 2020, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.

How we build fire pages: methodology

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.