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Loreto fire, September 2024 Loreto

Out · last detection 14 Sept 2024, 04:07 UTC

The fire started on 3 September 2024 in Loreto, Brazil, and satellites saw it burning for 12 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 10,062 hectares from heat detections, spread across a single municipality.

It is the 56th largest in Maranhão since 2016 (of 607 with a page). Number 318 in Brazil in 2024, of 1301.

Compare with…
Burnt area
10,062ha
GWIS perimeter (Copernicus)
Duration
12days
3 Sept 2024 – 14 Sept 2024
Municipalities hit
1
municipalities
Started on
3 Sept
2024
Heat detections
411
in a single hotspot: 0 MW
Danger at start
50
Very high · FWI index
Average daily power
263MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 3 Sept14 Sept
14 Sept 2024

How it evolved, day by day

3 Sept 2024 · 364 MW · 43 4 Sept 2024 · 452 MW · 49 5 Sept 2024 · 612 MW · 57 6 Sept 2024 · 680 MW · 98 7 Sept 2024 · 545 MW · 74 8 Sept 2024 · 99 MW · 29 9 Sept 2024 · 226 MW · 27 10 Sept 2024 · 84 MW · 11 11 Sept 2024 · 56 MW · 10 12 Sept 2024 · 11 MW · 5 13 Sept 2024 · 30 MW · 7 14 Sept 2024 · 1 MW · 1
3 Sept 5 Sept 6 Sept 7 Sept 9 Sept 11 Sept 13 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
49km/h · peak gust
16%lowest humidity

It had gone 21 days without rain (1 mm or more) when it started.

This area had burned before

58% of the perimeter overlaps earlier fires recorded since 2016: 602 ha in 2016, 1,142 ha in 2017, 866 ha in 2018, 903 ha in 2019, 2,287 ha in 2021, 1,255 ha in 2022, 3,619 ha in 2023. Part of it burned more than once, so the yearly figures add up to more than the 5,875 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 6.4% of the area of London (101 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. Loreto 11,597 inhabitants where it started
    10,131 ha
    2.8 %

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 2025
Built-up area0.81 ha
Residents≈ 60

Inside the perimeter there were about 0.81 hectares of built-up land and about 60 residents (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)
3 Sept 37.1 °C 17 % 36 km/h 0.0 mm Very high 50
4 Sept 37.5 °C 16 % 36 km/h 0.0 mm Very high 50
5 Sept 37.0 °C 20 % 39 km/h 0.0 mm Extreme 52
6 Sept 36.5 °C 23 % 42 km/h 0.0 mm Extreme 52
7 Sept 37.3 °C 21 % 44 km/h 0.0 mm Extreme 54
8 Sept 36.7 °C 21 % 46 km/h 0.0 mm Extreme 56
9 Sept 36.3 °C 20 % 49 km/h 0.0 mm Extreme 59
10 Sept 36.8 °C 23 % 43 km/h 0.0 mm Extreme 54
11 Sept 36.9 °C 24 % 41 km/h 0.0 mm Extreme 51
12 Sept 37.3 °C 21 % 44 km/h 0.0 mm Extreme 54
13 Sept 36.9 °C 22 % 48 km/h 0.0 mm Extreme 57
14 Sept 37.2 °C 20 % 40 km/h 0.0 mm Extreme 52
15 Sept after 37.5 °C 22 % 41 km/h 0.0 mm Extreme 52
16 Sept after 38.7 °C 22 % 37 km/h 0.0 mm Very high 50
17 Sept after 38.4 °C 21 % 37 km/h 0.0 mm Very high 50
18 Sept after 37.4 °C 21 % 47 km/h 0.0 mm Extreme 57
19 Sept after 37.4 °C 23 % 41 km/h 0.0 mm Extreme 53
20 Sept after 37.8 °C 23 % 42 km/h 0.0 mm Extreme 54
21 Sept after 37.9 °C 23 % 41 km/h 0.0 mm Extreme 52
22 Sept after 38.2 °C 20 % 40 km/h 0.0 mm Extreme 52
23 Sept after 38.2 °C 21 % 39 km/h 0.0 mm Extreme 52
24 Sept after 37.8 °C 24 % 38 km/h 0.0 mm Extreme 52

Before and after, from space

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

Before · 27 Aug 2024
After · 21 Sept 2024

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 4 September 2024 the air beside the fire reached 26 µg/m³ of PM2.5. That day averaged 15: 1.0 times the WHO daily guideline (15).

PM2.5 peak26 µg/m³
Days over the guideline2 days
PM1037 µg/m³
Optical depth0.45
1234567891011121314151617
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 · 0Every 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 Loreto fire last?
GWIS (Copernicus) dates it between 3 September 2024 and 14 September 2024: 12 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 10,062 hectares (100.6 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Loreto (10,131 ha, 2.8 %).
What was the weather like?
During the fire the temperature reached 37.5 °C, humidity dropped to 16 % and gusts hit 49 km/h. The fire danger index (FWI) reached 59, 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. Start date: 29 August 2024 → 3 September 2024.
  2. Start date: 3 September 2024 → 29 August 2024.

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.
  • Dates from the perimeter: the VIIRS detections inside it did not change them. No 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.

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.