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Mongkol Borei fire, December 2025 Ou Chrov, Mongkol Borei, Bavel

Out · last detection 21 Jan 2026, 05:44 UTC

The fire started on 25 December 2025 in Mongkol Borei, Cambodia, and satellites saw it burning for 27 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 12,657 hectares from heat detections, spread across 4 municipalities.

It is the largest fire in Banteay Meanchey since 2016 (of 14 with a page). Number 3 in Cambodia in 2025, of 28.

Compare with…
Burnt area
12,657ha
GWIS perimeter (Copernicus)
Duration
27days
25 Dec 2025 – 20 Jan 2026
Municipalities hit
4
districts
Started on
25 Dec
2025
Heat detections
362
in a single hotspot: 63 MW
Danger at start
23
High · FWI index
Average daily power
97MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 25 Dec20 Jan
21 Jan 2026

How it evolved, day by day

25 Dec 2025 · 29 MW · 7 26 Dec 2025 · 16 MW · 2 28 Dec 2025 · 7 MW · 2 29 Dec 2025 · 153 MW · 15 30 Dec 2025 · 74 MW · 20 31 Dec 2025 · 215 MW · 11 1 Jan 2026 · 28 MW · 4 2 Jan 2026 · 197 MW · 27 3 Jan 2026 · 512 MW · 49 4 Jan 2026 · 290 MW · 30 5 Jan 2026 · 125 MW · 17 6 Jan 2026 · 76 MW · 23 7 Jan 2026 · 224 MW · 40 8 Jan 2026 · 102 MW · 30 9 Jan 2026 · 21 MW · 6 10 Jan 2026 · 68 MW · 11 11 Jan 2026 · 23 MW · 3 12 Jan 2026 · 176 MW · 18 13 Jan 2026 · 77 MW · 11 14 Jan 2026 · 23 MW · 3 15 Jan 2026 · 5 MW · 3 16 Jan 2026 · 61 MW · 8 17 Jan 2026 · 31 MW · 4 18 Jan 2026 · 18 MW · 5 19 Jan 2026 · 41 MW · 7 20 Jan 2026 · 27 MW · 5 21 Jan 2026 · 6 MW · 1
25 Dec 30 Dec 3 Jan 7 Jan 11 Jan 15 Jan 19 Jan

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

The weather it burned in

35°high
43km/h · peak gust
35%lowest humidity

It had gone 14 days without rain (1 mm or more) when it started.

This area had burned before

79% of the perimeter overlaps earlier fires recorded since 2016: 2,932 ha in 2016, 2,174 ha in 2017, 4,574 ha in 2018, 3,401 ha in 2019, 1,132 ha in 2020, 330 ha in 2023, 2,904 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 10,001 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 8% of the area of London (127 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. 5,670 ha reached on 25 Dec
    10 %
  2. Mongkol Borei where it started
    4,703 ha reached on 26 Dec
    5.8 %
  3. 1,314 ha reached on 25 Dec
    1.4 %
  4. 1,043 ha reached on 29 Dec
    2.1 %

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 area34 ha
Residents≈ 4,700

Inside the perimeter there were about 34 hectares of built-up land and about 4,700 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)
25 Dec 33.9 °C 37 % 39 km/h 0.0 mm High 23
26 Dec 29.9 °C 54 % 43 km/h 0.0 mm Moderate 21
27 Dec 30.7 °C 49 % 31 km/h 0.0 mm Moderate 18
28 Dec 31.1 °C 47 % 32 km/h 0.0 mm Moderate 19
29 Dec 31.9 °C 41 % 27 km/h 0.0 mm Moderate 18
30 Dec 31.7 °C 35 % 28 km/h 0.0 mm Moderate 20
31 Dec 32.1 °C 37 % 22 km/h 0.0 mm Moderate 19
1 Jan 32.6 °C 35 % 23 km/h 0.0 mm Moderate 21
2 Jan 31.6 °C 43 % 32 km/h 0.0 mm High 24
3 Jan 30.4 °C 42 % 32 km/h 0.0 mm High 24
4 Jan 30.5 °C 42 % 30 km/h 0.0 mm High 25
5 Jan 31.8 °C 41 % 28 km/h 0.0 mm High 24
6 Jan 30.9 °C 46 % 37 km/h 0.0 mm High 26
7 Jan 29.1 °C 45 % 41 km/h 0.0 mm High 27
8 Jan 28.0 °C 41 % 42 km/h 0.0 mm High 28
9 Jan 27.6 °C 43 % 36 km/h 0.0 mm High 26
10 Jan 28.5 °C 37 % 28 km/h 0.0 mm High 24
11 Jan 28.8 °C 39 % 33 km/h 0.0 mm High 25
12 Jan 30.3 °C 39 % 26 km/h 0.0 mm High 24
13 Jan 31.9 °C 37 % 31 km/h 0.0 mm High 25
14 Jan 32.7 °C 40 % 20 km/h 0.0 mm Moderate 21
15 Jan 33.8 °C 38 % 20 km/h 0.0 mm High 22
16 Jan 33.4 °C 43 % 19 km/h 0.0 mm High 23
17 Jan 33.5 °C 46 % 20 km/h 0.1 mm High 24
18 Jan 33.9 °C 45 % 25 km/h 0.1 mm High 25
19 Jan 33.6 °C 43 % 20 km/h 0.2 mm High 25
20 Jan 35.1 °C 35 % 21 km/h 0.0 mm High 26
21 Jan after 33.2 °C 40 % 31 km/h 0.0 mm High 31
22 Jan after 31.9 °C 34 % 33 km/h 0.0 mm High 30
23 Jan after 31.3 °C 36 % 29 km/h 0.0 mm High 29
24 Jan after 31.3 °C 37 % 28 km/h 0.0 mm High 29
25 Jan after 32.6 °C 37 % 30 km/h 0.0 mm High 29
26 Jan after 32.6 °C 37 % 24 km/h 0.0 mm High 27
27 Jan after 32.8 °C 34 % 32 km/h 0.0 mm High 31
28 Jan after 32.2 °C 37 % 33 km/h 0.0 mm High 31
29 Jan after 33.0 °C 36 % 31 km/h 0.0 mm High 31
30 Jan after 34.0 °C 36 % 20 km/h 0.0 mm High 28

Before and after, from space

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

Before · 18 Dec 2025
After · 27 Jan 2026

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 14 January 2026 the air beside the fire reached 47 µg/m³ of PM2.5. That day averaged 31: 2.0 times the WHO daily guideline (15).

PM2.5 peak47 µg/m³
Days over the guideline12 days
PM1048 µg/m³
Optical depth0.58
23242526272829303112345678910111213141516
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 · 362Every 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 Cambodia ›

Frequently asked questions

How long did the Mongkol Borei fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 25 December 2025 to 20 January 2026 (27 days). The perimeter dates it from 25 December 2025 to 13 January 2026.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 12,657 hectares (126.6 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 4 municipalities: Ou Chrov (5,670 ha, 10 %); Mongkol Borei (4,703 ha, 5.8 %); Bavel (1,314 ha, 1.4 %); Malai (1,043 ha, 2.1 %).
What was the weather like?
During the fire the temperature reached 35.1 °C, humidity dropped to 35 % and gusts hit 43 km/h. The fire danger index (FWI) reached 28, 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 · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 13 January 2026 → 20 January 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.

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How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 2 polygons grouped in this page.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 25 December 2025 to 13 January 2026. 362 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.