Burned area
satellite only9,177ha
Union of 4 GWIS (Copernicus) perimeters: overlapping areas count once.
- Source
- GWIS (Copernicus)
- Date
- 8 Aug 2026 – 8 Sept 2026
+− cross-check
No official record is matched to this page to compare it with.
ID · Indonesia · –
Gunung Mas fire, 8 August 2026 Gunung Mas
Out · last detection 3 Sept 2026, 18:09 UTC
The fire started on 8 August 2026 in Gunung Mas, Indonesia, and satellites saw it burning for 32 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 9,177 hectares from heat detections, spread across a single municipality.
Number 69 in Indonesia in 2026, of 981.
GWIS near-real-time perimeter, from the layer that changed in October 2025: this fire is not compared with fires from earlier years, because since then the GWIS layer gives more and larger perimeters.
Use this data
Compare with…
Use this data
Fire page data · version 2026-11-05matches the official recordwith caveatssatellite onlymodel
When copying, the sentence is
Tick the figures you want: they make up the lede and the CSV.
Duration by satellite
satellite only32days
8 Aug 2026 to 8 Sept 2026: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 3 Sept 2026, 18:09 UTC
+− cross-check
Satellites pass a few times a day and cloud or smoke can hide the fire: a lack of detections is not an official extinction. Each country’s emergency service declares a fire contained or out.
Start
satellite only8 Aug 2026
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 8 Aug 2026
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only235
VIIRS detections at 375 m. Most intense hotspot: 53 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 8 Aug 2026 – 8 Sept 2026
+− cross-check
There is no official record to compare with. Each hotspot is a pixel detected in one satellite pass, not a separate fire.
The worst day
satellite only504MW
Total radiative power on 30 August 2026; hotspots that day: 41.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 30 Aug 2026
+− cross-check
Fire radiative power (FRP) measures the energy the fire gives off when the satellite passes. Added up by day, it compares intensity, not area.
Danger at the start
model18.4FWI · moderate
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 8.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 8 Aug 2026, local noon
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings
Weather during the fire
model36.2°C · 34% RH
High of 36.2 °C and minimum humidity of 34% on 18 August 2026; gusts of 27 km/h on 28 August 2026.
- Source
- weather model at the fire’s grid cell
- Date
- 8 Aug 2026 – 8 Sept 2026
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
Living inside
model≈ 2,900people
Estimated residents inside the perimeter and 8.4 ha of built-up area (100 m grid, epoch 2025).
- Source
- GHSL R2023A · JRC
- Date
- calculated on 24 October 2026
+− cross-check
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.
This page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
logArea: 9,589 → 9,177 ha.
-
· reconstructed GHSLPopulation and built-up area computed
What was saved on 5 November 2026
Every night a snapshot of what the page shows is saved. If anything changes, it appears in the list as a log entry.
- Area
- 9,177 ha
- Dates
- 8 Aug 2026 – 8 Sept 2026
- Name
- Gunung Mas
- Official record
- —
Versioned permanent link
https://worldfires.org/en/fire/gunung-mas-2026-08?v=2026-11-05A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire gunung-mas-2026-08.csv · daily, no individual hotspots
| fecha | focos_viirs | frp_mw | tmax_c | tmin_c | hr_min_pct | viento_max_kmh | racha_max_kmh | precip_mm | fwi | clase_fwi | dentro_del_incendio |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026-08-08 | 2 | 26 | 34.4 | 21.1 | 43 | 10.5 | 20.2 | 0 | 18.4 | moderado | 1 |
| 2026-08-09 | 0 | 0 | 34 | 22.4 | 39 | 9 | 19.1 | 0 | 18 | moderado | 1 |
| 2026-08-10 | 3 | 16 | 34.3 | 20.5 | 42 | 8.4 | 20.2 | 0 | 18.8 | moderado | 1 |
| 2026-08-11 | 10 | 33 | 34.6 | 20.2 | 44 | 8.9 | 17.3 | 0 | 18.2 | moderado | 1 |
| 2026-08-12 | 1 | 12 | 33.6 | 21.7 | 46 | 8.6 | 17.6 | 0 | 17.8 | moderado | 1 |
| 2026-08-13 | 14 | 79 | 33.6 | 22.8 | 49 | 9.3 | 16.9 | 0 | 18 | moderado | 1 |
| 2026-08-14 | 1 | 3 | 35.4 | 23.3 | 50 | 8 | 17.3 | 1.8 | 19.2 | moderado | 1 |
| 2026-08-15 | 0 | 0 | 33.8 | 23.6 | 53 | 7.8 | 20.5 | 0.4 | 10.8 | bajo | 1 |
| 2026-08-16 | 14 | 163 | 34.7 | 22.7 | 43 | 7.1 | 18.4 | 0.2 | 17.5 | moderado | 1 |
| 2026-08-17 | 12 | 271 | 35.4 | 21.9 | 38 | 11.1 | 23.8 | 0 | 23.7 | alto | 1 |
| 2026-08-18 | 27 | 263 | 36.2 | 21.8 | 34 | 8.3 | 23.4 | 0 | 27.6 | alto | 1 |
| 2026-08-19 | 7 | 52 | 35.7 | 20.7 | 34 | 10.9 | 19.4 | 0 | 26.8 | alto | 1 |
| 2026-08-20 | 3 | 7 | 35.1 | 22 | 41 | 10.2 | 20.9 | 0 | 22.2 | alto | 1 |
| 2026-08-21 | 3 | 6 | 35.3 | 21.3 | 41 | 8.8 | 19.8 | 0 | 24.4 | alto | 1 |
| 2026-08-22 | 0 | 0 | 33 | 22.1 | 52 | 8.7 | 18 | 0 | 23 | alto | 1 |
| 2026-08-23 | 0 | 0 | 33.4 | 23.1 | 54 | 9 | 19.8 | 0 | 22.8 | alto | 1 |
| 2026-08-24 | 0 | 0 | 34.5 | 22.9 | 51 | 8.5 | 24.1 | 0 | 24.5 | alto | 1 |
| 2026-08-25 | 1 | 2 | 35.6 | 21.6 | 42 | 8.7 | 22 | 0 | 25.2 | alto | 1 |
| 2026-08-26 | 8 | 46 | 35.8 | 21.1 | 38 | 10 | 19.1 | 0 | 25.4 | alto | 1 |
| 2026-08-27 | 12 | 27 | 35.6 | 21.2 | 37 | 9.4 | 21.2 | 0 | 27.3 | alto | 1 |
| 2026-08-28 | 17 | 68 | 35.7 | 20.9 | 28 | 10.6 | 27.4 | 0 | 37.1 | alto | 1 |
| 2026-08-29 | 30 | 121 | 35.6 | 20.9 | 34 | 10.9 | 20.9 | 0 | 32.9 | alto | 1 |
| 2026-08-30 | 41 | 504 | 35 | 21.3 | 41 | 10.5 | 18.7 | 0 | 27.5 | alto | 1 |
| 2026-08-31 | 5 | 28 | 35.7 | 22.1 | 43 | 12.4 | 24.5 | 0 | 28 | alto | 1 |
| 2026-09-01 | 13 | 69 | 35.7 | 23 | 39 | 11.1 | 20.9 | 0 | 26 | alto | 1 |
| 2026-09-02 | 2 | 3 | 35.4 | 21.8 | 39 | 11.2 | 23.8 | 0 | 26.5 | alto | 1 |
| 2026-09-03 | 9 | 22 | 34.1 | 22.7 | 46 | 10 | 20.2 | 0 | 23.8 | alto | 1 |
| 2026-09-04 | 0 | 0 | 34.3 | 22.6 | 47 | 9.4 | 20.5 | 0.2 | 27.3 | alto | 1 |
| 2026-09-05 | 0 | 0 | 34.4 | 23.2 | 46 | 9.1 | 24.8 | 0.1 | 29.5 | alto | 1 |
| 2026-09-06 | 0 | 0 | 34.3 | 22.9 | 45 | 11.3 | 24.5 | 0 | 27.6 | alto | 1 |
| 2026-09-07 | 0 | 0 | 33.5 | 25 | 52 | 10.4 | 22.3 | 1.1 | 22.8 | alto | 1 |
| 2026-09-08 | 0 | 0 | 33.6 | 24.9 | 54 | 7.1 | 23 | 1.4 | 7.3 | bajo | 1 |
| 2026-09-09 | 0 | 0 | 34.5 | 24.8 | 51 | 6.9 | 23.8 | 0.6 | 14.8 | moderado | 0 |
| 2026-09-10 | 0 | 0 | 34.9 | 24 | 48 | 8.8 | 25.2 | 0.2 | 25.3 | alto | 0 |
| 2026-09-11 | 0 | 0 | 36.3 | 23.9 | 36 | 10.7 | 24.1 | 0 | 31.3 | alto | 0 |
| 2026-09-12 | 0 | 0 | 35.4 | 23.6 | 44 | 9.8 | 22 | 0.2 | 28.4 | alto | 0 |
| 2026-09-13 | 0 | 0 | 34.5 | 24.2 | 48 | 9.6 | 27.4 | 0.4 | 31.6 | alto | 0 |
| 2026-09-14 | 0 | 0 | 35.7 | 23.2 | 36 | 12.9 | 26.3 | 0 | 32.3 | alto | 0 |
| 2026-09-15 | 0 | 0 | 35.6 | 22.7 | 39 | 9.2 | 20.2 | 0.3 | 29 | alto | 0 |
| 2026-09-16 | 0 | 0 | 32.1 | 24.5 | 48 | 7.8 | 21.6 | 1.7 | 25.3 | alto | 0 |
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: GWIS (Copernicus), NASA FIRMS (VIIRS), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0), GHSL (JRC). Open-Meteo.com · How we build fire pages: methodology
- Burnt area
- 9,177ha
- GWIS perimeter (Copernicus)
- Duration
- 32days
- 8 Aug 2026 – 8 Sept 2026
- Municipalities hit
- 1
- regencies
- Started on
- 8 Aug
- 2026
- Heat detections
- 235
- in a single hotspot: 53 MW
- Danger at start
- 18
- Moderate · FWI index
- Average daily power
- 83MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
8 Aug8 Sept
3 Sept 2026
How it evolved, day by day
8 Aug
14 Aug
20 Aug
30 Aug
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
36°high
27km/h · peak gust
28%lowest humidity
It had gone 8 days without rain (1 mm or more) when it started. Rain came after the fire: 1.7 mm on 16 Sept.
This area had burned before
No earlier perimeters overlap this fire since 2016, when the satellite record begins.
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Jakarta boundary: geoBoundaries · Badan Pusat Statistik (BPS - Statistics Indonesia), World Food Programme, OCHA ROAP (CC BY 3.0 IGO).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
Gunung Mas where it started9,655 ha reached on 8 Aug1.0 %
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 2025Built-up area8.4 ha
Residents≈ 2,900
Inside the perimeter there were about 8.4 hectares of built-up land and about 2,900 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) |
|---|---|---|---|---|---|
| 8 Aug | 34.4 °C | 43 % | 20 km/h | 0.0 mm | Moderate 18 |
| 9 Aug | 34.0 °C | 39 % | 19 km/h | 0.0 mm | Moderate 18 |
| 10 Aug | 34.3 °C | 42 % | 20 km/h | 0.0 mm | Moderate 19 |
| 11 Aug | 34.6 °C | 44 % | 17 km/h | 0.0 mm | Moderate 18 |
| 12 Aug | 33.6 °C | 46 % | 18 km/h | 0.0 mm | Moderate 18 |
| 13 Aug | 33.6 °C | 49 % | 17 km/h | 0.0 mm | Moderate 18 |
| 14 Aug | 35.4 °C | 50 % | 17 km/h | 1.8 mm | Moderate 19 |
| 15 Aug | 33.8 °C | 53 % | 20 km/h | 0.4 mm | Low 11 |
| 16 Aug | 34.7 °C | 43 % | 18 km/h | 0.2 mm | Moderate 18 |
| 17 Aug | 35.4 °C | 38 % | 24 km/h | 0.0 mm | High 24 |
| 18 Aug | 36.2 °C | 34 % | 23 km/h | 0.0 mm | High 28 |
| 19 Aug | 35.7 °C | 34 % | 19 km/h | 0.0 mm | High 27 |
| 20 Aug | 35.1 °C | 41 % | 21 km/h | 0.0 mm | High 22 |
| 21 Aug | 35.3 °C | 41 % | 20 km/h | 0.0 mm | High 24 |
| 22 Aug | 33.0 °C | 52 % | 18 km/h | 0.0 mm | High 23 |
| 23 Aug | 33.4 °C | 54 % | 20 km/h | 0.0 mm | High 23 |
| 24 Aug | 34.5 °C | 51 % | 24 km/h | 0.0 mm | High 24 |
| 25 Aug | 35.6 °C | 42 % | 22 km/h | 0.0 mm | High 25 |
| 26 Aug | 35.8 °C | 38 % | 19 km/h | 0.0 mm | High 25 |
| 27 Aug | 35.6 °C | 37 % | 21 km/h | 0.0 mm | High 27 |
| 28 Aug | 35.7 °C | 28 % | 27 km/h | 0.0 mm | High 37 |
| 29 Aug | 35.6 °C | 34 % | 21 km/h | 0.0 mm | High 33 |
| 30 Aug | 35.0 °C | 41 % | 19 km/h | 0.0 mm | High 28 |
| 31 Aug | 35.7 °C | 43 % | 24 km/h | 0.0 mm | High 28 |
| 1 Sept | 35.7 °C | 39 % | 21 km/h | 0.0 mm | High 26 |
| 2 Sept | 35.4 °C | 39 % | 24 km/h | 0.0 mm | High 26 |
| 3 Sept | 34.1 °C | 46 % | 20 km/h | 0.0 mm | High 24 |
| 4 Sept | 34.3 °C | 47 % | 20 km/h | 0.2 mm | High 27 |
| 5 Sept | 34.4 °C | 46 % | 25 km/h | 0.1 mm | High 30 |
| 6 Sept | 34.3 °C | 45 % | 24 km/h | 0.0 mm | High 28 |
| 7 Sept | 33.5 °C | 52 % | 22 km/h | 1.1 mm | High 23 |
| 8 Sept | 33.6 °C | 54 % | 23 km/h | 1.4 mm | Low 7 |
| 9 Sept after | 34.5 °C | 51 % | 24 km/h | 0.6 mm | Moderate 15 |
| 10 Sept after | 34.9 °C | 48 % | 25 km/h | 0.2 mm | High 25 |
| 11 Sept after | 36.3 °C | 36 % | 24 km/h | 0.0 mm | High 31 |
| 12 Sept after | 35.4 °C | 44 % | 22 km/h | 0.2 mm | High 28 |
| 13 Sept after | 34.5 °C | 48 % | 27 km/h | 0.4 mm | High 32 |
| 14 Sept after | 35.7 °C | 36 % | 26 km/h | 0.0 mm | High 32 |
| 15 Sept after | 35.6 °C | 39 % | 20 km/h | 0.3 mm | High 29 |
| 16 Sept after | 32.1 °C | 48 % | 22 km/h | 1.7 mm | High 25 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 1 Aug 2026
After · 15 Sept 2026
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
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 · CopernicusOn 19 August 2026 the air beside the fire reached 293 µg/m³ of PM2.5. That day averaged 204: 14 times the WHO daily guideline (15).
PM2.5 peak293 µg/m³
Days over the guideline16 days
PM10300 µg/m³
Optical depth4.20
WHO 15
9 Aug13 Aug17 Aug21 Aug
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 · 235Every 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 time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 4,229 haGunung Mas26 August 2026 · 12 days · 11 km away
- 2,493 haGunung Mas25 August 2026 · 11 days · 14 km away
- 2,935 haGunung Mas23 August 2026 · 13 days · 20 km away
- 4,265 haGunung Mas8 August 2026 · 28 days · 25 km away
- 3,473 haGunung Mas18 August 2026 · 20 days · 25 km away
- 3,204 haGunung MasSeptember 2019 · 6 days · 25 km away
Frequently asked questions
- How long did the Gunung Mas fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 8 August 2026 to 8 September 2026 (32 days). The perimeter dates it from 11 August 2026 to 8 September 2026.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 9,177 hectares (91.8 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Gunung Mas (9,655 ha, 1.0 %).
- What was the weather like?
- During the fire the temperature reached 36.2 °C, humidity dropped to 28 % and gusts hit 27 km/h. The fire danger index (FWI) reached 37, class High.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Indonesia (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: 112 · 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.
- Area: 9,589 → 9,177 ha.
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
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 4 polygons grouped in this page.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 11 August 2026 to 8 September 2026. 235 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.
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.