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AU · Australia · –

West Arnhem fire, 17 September 2023 West Arnhem

Out · last detection 15 Oct 2023, 04:34 UTC

The fire started on 17 September 2023 in West Arnhem, Australia, and satellites saw it burning for 29 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 14,248 hectares from heat detections, spread across a single municipality.

This entry is probably a savanna fire in Australia’s tropical north, not a bushfire like those in the south of the country. Millions of hectares of northern savanna and grassland burn every year: much of it in burns lit on purpose early in the dry season (traditional fire management, parks and cattle stations), the rest in grass fires that return to the same ground every few years. This is our assumption, based on the location; it is not confirmed. That is why it is left out of the wildfire rankings.

Compare with…

Suggestions: West Arnhem · 2020West Arnhem · 2018West Arnhem · 2016West Arnhem · 2019

Burnt area
14,248ha
GWIS perimeter (Copernicus)
Duration
29days
17 Sept 2023 – 15 Oct 2023
Municipalities hit
1
local government areas
Started on
17 Sept
2023
Heat detections
802
in a single hotspot: 151 MW
Danger at start
30
High · FWI index
Average daily power
288MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 17 Sept15 Oct
15 Oct 2023

How it evolved, day by day

17 Sept 2023 · 10 MW · 3 18 Sept 2023 · 143 MW · 14 19 Sept 2023 · 1,129 MW · 39 20 Sept 2023 · 182 MW · 18 21 Sept 2023 · 107 MW · 17 22 Sept 2023 · 64 MW · 14 23 Sept 2023 · 171 MW · 23 24 Sept 2023 · 558 MW · 42 25 Sept 2023 · 145 MW · 33 26 Sept 2023 · 388 MW · 40 27 Sept 2023 · 712 MW · 60 28 Sept 2023 · 1,470 MW · 97 29 Sept 2023 · 633 MW · 70 30 Sept 2023 · 277 MW · 35 1 Oct 2023 · 92 MW · 21 2 Oct 2023 · 214 MW · 43 3 Oct 2023 · 503 MW · 48 4 Oct 2023 · 288 MW · 23 5 Oct 2023 · 256 MW · 27 6 Oct 2023 · 261 MW · 44 7 Oct 2023 · 181 MW · 41 8 Oct 2023 · 20 MW · 5 9 Oct 2023 · 87 MW · 20 10 Oct 2023 · 114 MW · 13 11 Oct 2023 · 20 MW · 6 13 Oct 2023 · 6 MW · 1 14 Oct 2023 · 27 MW · 3 15 Oct 2023 · 17 MW · 2
17 Sept 23 Sept 28 Sept 5 Oct 11 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

29°high
46km/h · peak gust
53%lowest humidity

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

This area had burned before

100% of the perimeter overlaps earlier fires recorded since 2016: 10,737 ha in 2016, 13,937 ha in 2018, 332 ha in 2019, 13,481 ha in 2020, 809 ha in 2021, 7,269 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 14,221 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 9% of the area of London (142 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. West Arnhem where it started
    14,139 ha reached on 17 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 2025
Built-up area0.19 ha
Residents< 20

Inside the perimeter there were about 0.19 hectares of built-up land and almost nobody lived there (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)

Started with 60 days without rain: 8.2 % of the area in Australia

Day High Min. humidity Peak gust Rain Danger (FWI)
17 Sept 26.3 °C 54 % 46 km/h 0.0 mm High 30
18 Sept 26.8 °C 54 % 42 km/h 0.0 mm High 29
19 Sept 26.8 °C 53 % 41 km/h 0.1 mm High 28
20 Sept 26.6 °C 70 % 32 km/h 0.1 mm Moderate 18
21 Sept 26.8 °C 72 % 29 km/h 0.0 mm Moderate 16
22 Sept 26.9 °C 77 % 26 km/h 0.0 mm Moderate 14
23 Sept 26.9 °C 70 % 22 km/h 0.0 mm Moderate 12
24 Sept 27.4 °C 64 % 29 km/h 0.0 mm Moderate 16
25 Sept 26.9 °C 69 % 28 km/h 0.0 mm Moderate 16
26 Sept 27.0 °C 69 % 30 km/h 0.0 mm Moderate 16
27 Sept 27.2 °C 66 % 30 km/h 0.0 mm Moderate 16
28 Sept 27.8 °C 55 % 34 km/h 0.0 mm High 22
29 Sept 27.7 °C 56 % 33 km/h 0.0 mm High 22
30 Sept 28.1 °C 68 % 33 km/h 0.4 mm Moderate 20
1 Oct 27.3 °C 70 % 30 km/h 0.0 mm Moderate 18
2 Oct 27.4 °C 73 % 32 km/h 0.0 mm Moderate 18
3 Oct 26.8 °C 77 % 25 km/h 0.0 mm Moderate 13
4 Oct 27.0 °C 74 % 24 km/h 0.0 mm Moderate 14
5 Oct 27.7 °C 69 % 27 km/h 0.0 mm Moderate 16
6 Oct 28.5 °C 66 % 35 km/h 0.0 mm Moderate 20
7 Oct 28.6 °C 55 % 30 km/h 0.0 mm High 23
8 Oct 28.3 °C 67 % 32 km/h 0.0 mm High 22
9 Oct 28.2 °C 62 % 35 km/h 0.2 mm High 21
10 Oct 28.1 °C 67 % 35 km/h 1.1 mm Moderate 15
11 Oct 28.2 °C 64 % 32 km/h 0.0 mm Moderate 18
12 Oct 28.2 °C 70 % 27 km/h 0.0 mm Moderate 17
13 Oct 28.3 °C 71 % 27 km/h 0.0 mm Moderate 17
14 Oct 28.4 °C 65 % 32 km/h 0.1 mm Moderate 20
15 Oct 29.1 °C 61 % 32 km/h 0.0 mm Moderate 21
16 Oct after 28.3 °C 68 % 31 km/h 0.0 mm Moderate 20
17 Oct after 28.3 °C 68 % 28 km/h 0.0 mm Moderate 17
18 Oct after 28.1 °C 68 % 24 km/h 0.0 mm Moderate 19
19 Oct after 28.1 °C 72 % 32 km/h 0.0 mm Moderate 20
20 Oct after 28.3 °C 70 % 30 km/h 0.0 mm Moderate 18
21 Oct after 28.0 °C 73 % 35 km/h 0.0 mm Moderate 19
22 Oct after 27.6 °C 72 % 33 km/h 0.0 mm Moderate 17
23 Oct after 28.4 °C 67 % 27 km/h 0.0 mm Moderate 18
24 Oct after 28.8 °C 70 % 25 km/h 0.0 mm Moderate 18
25 Oct after 29.3 °C 67 % 28 km/h 0.0 mm Moderate 19

Before and after, from space

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

Before · 10 Sept 2023
After · 22 Oct 2023

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 October 2023 the air beside the fire reached 26 µg/m³ of PM2.5. That day averaged 16: 1.0 times the WHO daily guideline (15).

PM2.5 peak26 µg/m³
Days over the guideline1 day
PM1038 µg/m³
Optical depth0.53
15 Sept21 Sept27 Sept3 Oct9 Oct
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 · 802Every 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 Australia

Frequently asked questions

How long did the West Arnhem fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 17 September 2023 to 15 October 2023 (29 days). The perimeter dates it from 17 September 2023 to 11 October 2023.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 14,248 hectares (142.5 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered West Arnhem (14,139 ha, 0.3 %).
What was the weather like?
During the fire the temperature reached 29.1 °C, humidity dropped to 53 % and gusts hit 46 km/h. The fire danger index (FWI) reached 30, class High.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Australia (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: 000 · 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. Last day with fire: 11 October 2023 → 15 October 2023.

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 000.

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 2023 to 11 October 2023. 802 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.
  • Probably a vegetation burn: not counted in the totals.

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 4.0 International (CC BY 4.0)). 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.