Sesan fire, April 2026 Sesan
The fire started on 18 April 2026 in Sesan, Cambodia, and satellites saw it burning for 10 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 4,450 hectares from heat detections, spread across a single municipality.
It is the 37th largest in Stung Treng since 2016 (of 130 with a page). Number 31 in Cambodia in 2026, of 120.
Compare with…
Suggestions: Sesan · 2024Sesan · 2021Sesan · 2025Sesan · 2025
- Burnt area
- 4,450ha
- GWIS perimeter (Copernicus)
- Duration
- 10days
- 18 Apr 2026 – 27 Apr 2026
- Municipalities hit
- 1
- districts
- Started on
- 18 Apr
- 2026
- Heat detections
- 219
- in a single hotspot: 291 MW
- Danger at start
- 24
- High · FWI index
- Average daily power
- 368MW
- detected power per day, on average
Where it burned
How it evolved, day by day
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
It had gone 0 days without rain (1 mm or more) when it started. Rain came after the fire: 7.6 mm on 29 Apr.
This area had burned before
86% of the perimeter overlaps earlier fires recorded since 2016: 139 ha in 2016, 292 ha in 2019, 753 ha in 2020, 1,923 ha in 2021, 2,309 ha in 2022, 2,394 ha in 2024, 2,888 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 3,835 ha that had burned before.
- 2,394 ha Sesan fire, January 2024 6,102 ha in total; the hectares shown are those it shares with this fire
- 1,923 ha Sesan fire, January 2021 16,629 ha in total; the hectares shown are those it shares with this fire
- 823 ha Sesan fire, December 2025 30,976 ha in total; the hectares shown are those it shares with this fire
- 530 ha Sesan fire, January 2025 4,486 ha in total; the hectares shown are those it shares with this fire
- 292 ha Sesan fire, December 2019 13,216 ha in total; the hectares shown are those it shares with this fire
- 139 ha Sesan fire, January 2016 6,998 ha in total; the hectares shown are those it shares with this fire
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
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).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
Sesan where it started4,478 ha1.6 %
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.
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 Apr | 38.0 °C | 39 % | 24 km/h | 0.9 mm | High 24 |
| 19 Apr | 36.7 °C | 45 % | 28 km/h | 1.4 mm | Moderate 17 |
| 20 Apr | 36.4 °C | 43 % | 27 km/h | 2.6 mm | Low 11 |
| 21 Apr | 35.9 °C | 43 % | 29 km/h | 0.0 mm | Moderate 21 |
| 22 Apr | 37.0 °C | 41 % | 29 km/h | 0.1 mm | High 25 |
| 23 Apr | 37.1 °C | 41 % | 31 km/h | 0.0 mm | High 25 |
| 24 Apr | 36.8 °C | 45 % | 25 km/h | 0.3 mm | High 26 |
| 25 Apr | 36.8 °C | 43 % | 26 km/h | 1.0 mm | Moderate 20 |
| 26 Apr | 36.5 °C | 41 % | 30 km/h | 0.7 mm | High 24 |
| 27 Apr | 35.7 °C | 48 % | 23 km/h | 0.5 mm | High 22 |
| 28 Apr after | 32.8 °C | 54 % | 31 km/h | 0.6 mm | Moderate 18 |
| 29 Apr after | 37.2 °C | 41 % | 31 km/h | 7.6 mm | Low 6 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
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 24 April 2026 the air beside the fire reached 59 µg/m³ of PM2.5. That day averaged 41: 2.7 times the WHO daily guideline (15).
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 · 219Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
Frequently asked questions
- How long did the Sesan fire last?
- GWIS (Copernicus) dates it between 18 April 2026 and 27 April 2026: 10 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 4,450 hectares (44.5 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Sesan (4,478 ha, 1.6 %).
- What was the weather like?
- During the fire the temperature reached 38.0 °C, humidity dropped to 39 % and gusts hit 31 km/h. The fire danger index (FWI) reached 26, class High.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Cambodia (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.
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.
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.
- Dates from the perimeter: the VIIRS detections inside it did not change them. 219 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.
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.