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Montes Altos fire, August 2017 Montes Altos, Lajeado Novo, Sítio Novo

Out · last detection 1 Oct 2017, 17:10 UTC

The fire started on 26 August 2017 in Montes Altos, Brazil, and satellites saw it burning for 36 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 32,330 hectares from heat detections, spread across 4 municipalities.

It is the 6th largest in Maranhão since 2016 (of 607 with a page). Number 32 in Brazil in 2017, of 994.

Compare with…

Suggestions: Montes Altos · 2020Amarante do Maranhão · 2017Amarante do Maranhão · 2020Montes Altos · 2017

Burnt area
32,330ha
GWIS perimeter (Copernicus)
Duration
36days
26 Aug 2017 – 30 Sept 2017
Municipalities hit
4
municipalities
Started on
26 Aug
2017
Heat detections
1,952
in a single hotspot: 160 MW
Danger at start
40
Very high · FWI index
Average daily power
511MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 26 Aug30 Sept
1 Oct 2017

How it evolved, day by day

26 Aug 2017 · 170 MW · 21 27 Aug 2017 · 115 MW · 14 28 Aug 2017 · 4 MW · 2 30 Aug 2017 · 135 MW · 18 31 Aug 2017 · 429 MW · 57 1 Sept 2017 · 89 MW · 18 2 Sept 2017 · 114 MW · 14 3 Sept 2017 · 23 MW · 4 4 Sept 2017 · 73 MW · 28 5 Sept 2017 · 187 MW · 38 6 Sept 2017 · 871 MW · 124 7 Sept 2017 · 171 MW · 29 8 Sept 2017 · 250 MW · 22 9 Sept 2017 · 1,148 MW · 81 10 Sept 2017 · 2,713 MW · 148 11 Sept 2017 · 747 MW · 101 12 Sept 2017 · 1,981 MW · 198 13 Sept 2017 · 669 MW · 81 14 Sept 2017 · 525 MW · 62 15 Sept 2017 · 474 MW · 101 16 Sept 2017 · 1,391 MW · 127 17 Sept 2017 · 1,413 MW · 161 18 Sept 2017 · 462 MW · 49 19 Sept 2017 · 313 MW · 49 20 Sept 2017 · 160 MW · 28 21 Sept 2017 · 473 MW · 74 22 Sept 2017 · 739 MW · 87 23 Sept 2017 · 468 MW · 54 24 Sept 2017 · 26 MW · 10 25 Sept 2017 · 69 MW · 15 26 Sept 2017 · 678 MW · 50 27 Sept 2017 · 512 MW · 45 28 Sept 2017 · 261 MW · 30 30 Sept 2017 · 23 MW · 4 1 Oct 2017 · 22 MW · 8
26 Aug 1 Sept 6 Sept 10 Sept 11 Sept 16 Sept 21 Sept 26 Sept

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
53km/h · peak gust
23%lowest humidity

It had gone more than two months without rain (1 mm or more) when it started.

This area had burned before

11% of the perimeter overlaps earlier fires recorded since 2016: 3,594 ha in 2016. Part of it burned more than once, so the yearly figures add up to more than the 3,421 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 20% of the area of London (323 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. Montes Altos 9,106 inhabitants where it started
    21,402 ha reached on 26 Aug
    14 %
  2. Lajeado Novo 7,057 inhabitants
    7,295 ha reached on 30 Aug
    6.8 %
  3. Sítio Novo 17,074 inhabitants
    3,413 ha reached on 27 Aug
    1.1 %
  4. Amarante do Maranhão 37,085 inhabitants
    434 ha reached on 31 Aug
    0.1 %

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 2015
Built-up area1.6 ha
Residents≈ 250

Inside the perimeter there were about 1.6 hectares of built-up land and about 250 residents (GHSL 2015, 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)

Day High Min. humidity Peak gust Rain Danger (FWI)
26 Aug 36.2 °C 29 % 40 km/h 0.0 mm Very high 40
27 Aug 35.5 °C 35 % 42 km/h 0.0 mm Very high 41
28 Aug 36.3 °C 30 % 41 km/h 0.0 mm Very high 40
29 Aug 35.7 °C 32 % 38 km/h 0.0 mm Very high 38
30 Aug 36.6 °C 29 % 38 km/h 0.0 mm Very high 39
31 Aug 37.1 °C 31 % 37 km/h 0.0 mm Very high 38
1 Sept 34.8 °C 42 % 41 km/h 0.0 mm High 34
2 Sept 35.6 °C 34 % 44 km/h 0.0 mm High 36
3 Sept 35.8 °C 28 % 40 km/h 0.0 mm Very high 40
4 Sept 35.6 °C 24 % 51 km/h 0.0 mm Extreme 51
5 Sept 35.8 °C 28 % 46 km/h 0.0 mm Very high 48
6 Sept 35.9 °C 34 % 44 km/h 0.0 mm Very high 45
7 Sept 35.5 °C 38 % 43 km/h 0.0 mm Very high 40
8 Sept 36.7 °C 32 % 40 km/h 0.0 mm Very high 40
9 Sept 36.2 °C 30 % 44 km/h 0.0 mm Very high 42
10 Sept 37.0 °C 28 % 44 km/h 0.0 mm Very high 44
11 Sept 36.6 °C 27 % 40 km/h 0.0 mm Very high 42
12 Sept 36.9 °C 26 % 45 km/h 0.0 mm Very high 46
13 Sept 35.8 °C 31 % 43 km/h 0.0 mm Very high 44
14 Sept 37.1 °C 27 % 42 km/h 0.0 mm Very high 45
15 Sept 36.9 °C 27 % 40 km/h 0.0 mm Very high 44
16 Sept 36.4 °C 23 % 45 km/h 0.0 mm Very high 48
17 Sept 36.1 °C 28 % 48 km/h 0.0 mm Very high 50
18 Sept 36.6 °C 30 % 44 km/h 0.0 mm Very high 47
19 Sept 37.7 °C 30 % 39 km/h 0.0 mm Very high 46
20 Sept 37.0 °C 30 % 37 km/h 0.0 mm Very high 45
21 Sept 37.0 °C 28 % 41 km/h 0.0 mm Very high 48
22 Sept 36.5 °C 27 % 45 km/h 0.0 mm Extreme 51
23 Sept 36.3 °C 29 % 41 km/h 0.0 mm Very high 48
24 Sept 36.4 °C 27 % 43 km/h 0.0 mm Very high 49
25 Sept 35.3 °C 35 % 35 km/h 0.0 mm Very high 39
26 Sept 38.0 °C 29 % 38 km/h 0.0 mm Very high 42
27 Sept 37.1 °C 31 % 43 km/h 0.0 mm Very high 44
28 Sept 37.4 °C 28 % 48 km/h 0.0 mm Very high 44
29 Sept 38.2 °C 28 % 53 km/h 0.0 mm Very high 45
30 Sept 35.6 °C 37 % 40 km/h 0.0 mm High 36
1 Oct after 36.2 °C 32 % 38 km/h 0.0 mm Very high 40
2 Oct after 36.4 °C 37 % 36 km/h 0.0 mm Very high 41
3 Oct after 36.8 °C 41 % 34 km/h 0.2 mm High 36
4 Oct after 37.2 °C 30 % 33 km/h 0.0 mm High 35
5 Oct after 37.4 °C 29 % 44 km/h 0.0 mm Very high 41
6 Oct after 37.7 °C 30 % 42 km/h 0.0 mm Very high 42
7 Oct after 36.1 °C 33 % 34 km/h 0.0 mm Very high 40
8 Oct after 35.7 °C 37 % 36 km/h 0.0 mm High 37
9 Oct after 34.3 °C 49 % 27 km/h 0.0 mm High 28
10 Oct after 33.7 °C 43 % 36 km/h 0.2 mm High 30

Before and after, from space

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

Before · 19 Aug 2017
After · 7 Oct 2017

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 · 1,952Every 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 Montes Altos fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 26 August 2017 to 30 September 2017 (36 days). The perimeter dates it from 30 August 2017 to 27 September 2017.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 32,330 hectares (323.3 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 4 municipalities: Montes Altos (21,402 ha, 14 %); Lajeado Novo (7,295 ha, 6.8 %); Sítio Novo (3,413 ha, 1.1 %); Amarante do Maranhão (434 ha, 0.1 %).
What was the weather like?
During the fire the temperature reached 38.2 °C, humidity dropped to 23 % and gusts hit 53 km/h. The fire danger index (FWI) reached 51, 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 · 2 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 27 September 2017 → 30 September 2017.
  2. Start date: 30 August 2017 → 26 August 2017.

RSS Changes to this page

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; 2 polygons grouped in this page.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 30 August 2017 to 27 September 2017. 1,952 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 2015, 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.