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Loreto fire, 18 September 2017 Loreto

Out · last detection 23 Sept 2017, 16:19 UTC

The fire started on 18 September 2017 in Loreto, Brazil, and satellites saw it burning for 6 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,541 hectares from heat detections, spread across a single municipality.

It is the 437th largest in Maranhão since 2016 (of 607 with a page). Number 776 in Brazil in 2017, of 994.

The power measured by the satellite is low (29.9 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Burnt area
3,541ha
GWIS perimeter (Copernicus)
Duration
6days
18 Sept 2017 – 23 Sept 2017
Municipalities hit
1
municipalities
Started on
18 Sept
2017
Heat detections
184
in a single hotspot: 30 MW
Danger at start
49
Very high · FWI index
Energy released
1.3GW
sum of detected power

Where it burned

23 Sept 2017
HOTSPOTS BY DAY 18 Sept23 Sept

How it evolved, day by day

181920212223

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
48km/h · peak gust
21%lowest humidity

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

This area had burned before

No earlier perimeters overlap this fire since 2016, when the satellite record begins.

What happened to each town

  1. Loreto 11,597 inhabitants where it started
    3,564 ha reached on 17 Sept
    1.0 %

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)
11 Sept 36.3 °C 25 % 48 km/h 0.0 mm Very high 49
12 Sept 36.4 °C 25 % 46 km/h 0.0 mm Very high 48
13 Sept 35.9 °C 27 % 42 km/h 0.0 mm Very high 46
14 Sept 37.2 °C 25 % 44 km/h 0.0 mm Very high 48
15 Sept 36.4 °C 22 % 46 km/h 0.0 mm Very high 50
16 Sept 35.2 °C 25 % 46 km/h 0.0 mm Very high 49
17 Sept 36.1 °C 25 % 44 km/h 0.0 mm Very high 49
18 Sept 36.8 °C 25 % 44 km/h 0.0 mm Very high 49
19 Sept 37.8 °C 26 % 42 km/h 0.0 mm Very high 47
20 Sept 37.2 °C 24 % 43 km/h 0.0 mm Very high 50
21 Sept 37.3 °C 21 % 45 km/h 0.0 mm Extreme 51
22 Sept 36.5 °C 25 % 46 km/h 0.0 mm Extreme 52
23 Sept 36.9 °C 26 % 40 km/h 0.0 mm Very high 48
24 Sept after 36.4 °C 27 % 41 km/h 0.0 mm Very high 49
25 Sept after 36.5 °C 28 % 42 km/h 0.0 mm Very high 49
26 Sept after 38.1 °C 22 % 42 km/h 0.0 mm Very high 50
27 Sept after 37.9 °C 24 % 43 km/h 0.0 mm Extreme 50
28 Sept after 38.6 °C 25 % 46 km/h 0.0 mm Extreme 51
29 Sept after 38.4 °C 26 % 49 km/h 0.0 mm Extreme 53
30 Sept after 38.0 °C 23 % 42 km/h 0.0 mm Very high 49
1 Oct after 37.9 °C 24 % 40 km/h 0.0 mm Very high 48
2 Oct after 39.2 °C 23 % 36 km/h 0.0 mm Very high 46
3 Oct after 38.9 °C 25 % 37 km/h 0.0 mm Very high 46

Before and after, from space

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

Before · 11 Sept 2017
After · 30 Sept 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 · 184Every 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 18 September 2017 and 23 September 2017: 6 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 3,541 hectares (35.4 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Loreto (3,564 ha, 1.0 %).
What was the weather like?
During the fire the temperature reached 37.8 °C, humidity dropped to 21 % and gusts hit 48 km/h. The fire danger index (FWI) reached 52, 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

Satellite cross-check

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.

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.