Skip to content
worldfires
en
AU · Australia · →

Mount Isa fire, 18 September 2023 Barkly, Mount Isa

Out · last detection 9 Oct 2023, 04:44 UTC

The fire started on 18 September 2023 in Mount Isa, Australia, and satellites saw it burning for 22 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 81,229 hectares from heat detections, spread across 2 municipalities.

It is the 50th largest in Queensland since 2016 (of 1743 with a page). Number 48 in Australia in 2023, of 1235.

Compare with…

Suggestions: Mount Isa · 2017Barkly · 2025Barkly · 2025Barkly · 2023

Burnt area
81,229ha
GWIS perimeter (Copernicus)
Duration
22days
18 Sept 2023 – 9 Oct 2023
Municipalities hit
2
local government areas
Started on
18 Sept
2023
Heat detections
3,203
in a single hotspot: 425 MW
Danger at start
55
Extreme · FWI index
Average daily power
2.0GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 18 Sept9 Oct
9 Oct 2023

How it evolved, day by day

18 Sept 2023 · 584 MW · 57 19 Sept 2023 · 300 MW · 83 20 Sept 2023 · 716 MW · 110 21 Sept 2023 · 5,869 MW · 297 22 Sept 2023 · 1,019 MW · 148 23 Sept 2023 · 277 MW · 40 24 Sept 2023 · 573 MW · 59 25 Sept 2023 · 4,271 MW · 361 26 Sept 2023 · 7,237 MW · 486 27 Sept 2023 · 8,589 MW · 560 28 Sept 2023 · 10,860 MW · 534 29 Sept 2023 · 1,997 MW · 141 30 Sept 2023 · 211 MW · 32 1 Oct 2023 · 50 MW · 10 2 Oct 2023 · 201 MW · 38 3 Oct 2023 · 64 MW · 13 4 Oct 2023 · 197 MW · 24 5 Oct 2023 · 38 MW · 15 6 Oct 2023 · 258 MW · 73 7 Oct 2023 · 1,082 MW · 67 8 Oct 2023 · 189 MW · 45 9 Oct 2023 · 99 MW · 10
18 Sept 22 Sept 26 Sept 28 Sept 30 Sept 4 Oct 8 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

38°high
53km/h · peak gust
9%lowest humidity

It had gone 52 days without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 10 Oct.

This area had burned before

14% of the perimeter overlaps earlier fires recorded since 2016: 5,461 ha in 2016, 2,743 ha in 2017, 1,636 ha in 2018, 1,587 ha in 2020.

How big is it?

20 km
It burned the equivalent of 51% of the area of London (812 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. Barkly
    62,080 ha reached on 20 Sept
    0.2 %
  2. Mount Isa where it started
    19,156 ha reached on 18 Sept
    0.4 %

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 area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable 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)

Day High Min. humidity Peak gust Rain Danger (FWI)
18 Sept 32.5 °C 17 % 31 km/h 0.0 mm Extreme 55
19 Sept 33.5 °C 17 % 36 km/h 0.0 mm Extreme 60
20 Sept 35.2 °C 15 % 35 km/h 0.0 mm Extreme 57
21 Sept 37.6 °C 11 % 37 km/h 0.0 mm Extreme 66
22 Sept 36.7 °C 9 % 49 km/h 0.0 mm Very extreme 81
23 Sept 35.6 °C 9 % 44 km/h 0.0 mm Extreme 66
24 Sept 35.2 °C 13 % 44 km/h 0.0 mm Very extreme 74
25 Sept 34.9 °C 14 % 29 km/h 0.0 mm Extreme 60
26 Sept 35.3 °C 12 % 34 km/h 0.0 mm Extreme 63
27 Sept 35.1 °C 13 % 38 km/h 0.0 mm Extreme 67
28 Sept 34.9 °C 14 % 53 km/h 0.0 mm Very extreme 82
29 Sept 35.0 °C 13 % 42 km/h 0.0 mm Extreme 68
30 Sept 35.0 °C 21 % 44 km/h 0.0 mm Extreme 64
1 Oct 37.0 °C 11 % 35 km/h 0.0 mm Extreme 65
2 Oct 37.3 °C 13 % 38 km/h 0.0 mm Extreme 64
3 Oct 37.1 °C 17 % 37 km/h 0.0 mm Extreme 62
4 Oct 34.8 °C 21 % 34 km/h 0.0 mm Extreme 59
5 Oct 31.7 °C 13 % 43 km/h 0.0 mm Extreme 63
6 Oct 32.9 °C 9 % 44 km/h 0.0 mm Extreme 67
7 Oct 34.4 °C 9 % 42 km/h 0.0 mm Extreme 67
8 Oct 35.2 °C 15 % 41 km/h 0.0 mm Very extreme 70
9 Oct 33.2 °C 28 % 35 km/h 0.1 mm Very high 49
10 Oct after 31.9 °C 35 % 21 km/h 1.0 mm High 26

Before and after, from space

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

Before · 11 Sept 2023
After · 16 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 26 September 2023 the air beside the fire reached 179 µg/m³ of PM2.5. That day averaged 58: 3.9 times the WHO daily guideline (15).

PM2.5 peak179 µg/m³
Days over the guideline4 days
PM10257 µg/m³
Optical depth0.83
161718192021222324252627282930123456789101112
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 · 3,203Every 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 Mount Isa fire last?
GWIS (Copernicus) dates it between 18 September 2023 and 9 October 2023: 22 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 81,229 hectares (812.3 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Barkly (62,080 ha, 0.2 %); Mount Isa (19,156 ha, 0.4 %).
What was the weather like?
During the fire the temperature reached 37.6 °C, humidity dropped to 9 % and gusts hit 53 km/h. The fire danger index (FWI) reached 82, class Very extreme.
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 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.

No changes since 24 October 2026.

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 000.

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. 3,203 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 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.