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BR · Brazil · –

Balsas fire, 13 September 2022 Balsas, Lizarda

Out · last detection 20 Sept 2022, 16:38 UTC

The fire started on 13 September 2022 in Balsas, Brazil, and satellites saw it burning for 9 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 5,495 hectares from heat detections, spread across 2 municipalities.

It is the 170th largest in Maranhão since 2016 (of 531 with a page). Number 263 in Brazil in 2022, of 682.

Burnt area
5,495ha
GWIS perimeter (Copernicus)
Duration
9days
13 Sept 2022 – 21 Sept 2022
Municipalities hit
2
municipalities
Started on
13 Sept
2022
Heat detections
173
in a single hotspot: 172 MW
Danger at start
48
Very high · FWI index
Average daily power
563MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 13 Sept21 Sept
20 Sept 2022

How it evolved, day by day

17 Sept 2022 · 615 MW · 11 18 Sept 2022 · 812 MW · 48 19 Sept 2022 · 611 MW · 83 20 Sept 2022 · 214 MW · 31
17 Sept 18 Sept 19 Sept 20 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
42km/h · peak gust
16%lowest humidity

It had gone more than two months without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 23 Sept.

This area had burned before

11% of the perimeter overlaps earlier fires recorded since 2016: 90 ha in 2016, 507 ha in 2017, 7 ha in 2019, 4 ha in 2020.

How big is it?

10 km
It burned the equivalent of 3.5% of the area of London (55 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. Balsas 101,767 inhabitants where it started
    3,606 ha reached on 17 Sept
    0.3 %
  2. Lizarda 2,999 inhabitants
    1,931 ha reached on 18 Sept
    0.3 %

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 area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (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)
13 Sept 36.7 °C 18 % 34 km/h 0.0 mm Very high 48
14 Sept 36.8 °C 16 % 33 km/h 0.0 mm Very high 48
15 Sept 38.0 °C 16 % 20 km/h 0.0 mm Very high 44
16 Sept 36.0 °C 24 % 28 km/h 0.0 mm Very high 43
17 Sept 36.5 °C 17 % 37 km/h 0.0 mm Very high 48
18 Sept 36.2 °C 19 % 42 km/h 0.0 mm Extreme 54
19 Sept 35.9 °C 22 % 28 km/h 0.0 mm Very high 43
20 Sept 36.8 °C 23 % 42 km/h 0.0 mm Extreme 56
21 Sept 34.8 °C 25 % 40 km/h 0.0 mm Very high 50
22 Sept after 34.2 °C 35 % 27 km/h 0.1 mm High 34
23 Sept after 33.5 °C 40 % 30 km/h 1.0 mm High 24

Its twins: fires that started in the same weather

It started with an FWI of 47.7, a minimum humidity of 18% and more than two months without rain. Fires in the area that started in weather like this since 2016: 24.

FWI at the start 47.7
Minimum humidity 18 %
Days without rain 60+
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Balsas fire, September 2020
4,249 ha 14 days FWI 48.5 Min. humidity 18 % 19 km away, in 2020

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

What happened to them

9 days
median duration
3,886 ha
median area
12 %
went past 10,000 ha
3.2 mm
rain at the end (median; 14 of 24 had it)

It burned an area similar to its twins (5,495 ha against a median of 3,886 ha) and lasted 9 days, against 9 days.

In 10 of 24, 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 3.2 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

1.0 mmfirst rain
23 Sept2 days after it ended
42km/h · max. gust

It was considered over on 21 Sept, and on 23 Sept 1.0 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 14 of 24, with a median of 3.2 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 · 6 Sept 2022
After · 28 Sept 2022

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 19 September 2022 the air beside the fire reached 145 µg/m³ of PM2.5. That day averaged 63: 4.2 times the WHO daily guideline (15).

PM2.5 peak145 µg/m³
Days over the guideline10 days
PM10207 µg/m³
Optical depth0.83
15 Sept17 Sept19 Sept21 Sept23 Sept
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 · 173Every 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 Balsas fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 13 September 2022 to 21 September 2022 (9 days). The perimeter dates it from 17 September 2022 to 21 September 2022.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 5,495 hectares (55.0 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Balsas (3,606 ha, 0.3 %); Lizarda (1,931 ha, 0.3 %).
What was the weather like?
During the fire the temperature reached 38.0 °C, humidity dropped to 16 % and gusts hit 42 km/h. The fire danger index (FWI) reached 56, 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: 24. Their median duration was 9 days and their median area 3,886 ha; 12 % went past 10,000 ha. In 10 of 24, 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 3.2 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: 17 September 2022 → 13 September 2022.

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.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 17 September 2022 to 21 September 2022. 173 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.