Nalae fire, March 2025 Nalae, Hoon
The fire started on 26 March 2025 in Nalae, Laos, and satellites saw it burning for 10 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 2,490 hectares from heat detections, spread across 2 municipalities.
It is the 20th largest in Luang Namtha since 2016 (of 36 with a page). Number 26 in Laos in 2025, of 51.
- Burnt area
- 2,490ha
- GWIS perimeter (Copernicus)
- Duration
- 10days
- 26 Mar 2025 – 4 Apr 2025
- Municipalities hit
- 2
- districts
- Started on
- 26 Mar
- 2025
- Heat detections
- 77
- in a single hotspot: 755 MW
- Energy released
- 4.6GW
- sum of detected power
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.
This area had burned before
98% of the perimeter overlaps earlier fires recorded since 2016: 1,423 ha in 2017, 241 ha in 2018, 1,120 ha in 2019, 1,979 ha in 2020, 315 ha in 2023, 1,530 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 2,448 ha that had burned before.
- 1,979 ha Hoon fire, March 2020 7,519 ha in total; the hectares shown are those it shares with this fire
- 1,530 ha Nalae fire, March 2024 3,215 ha in total; the hectares shown are those it shares with this fire
- 1,423 ha Hoon fire, April 2017 4,307 ha in total; the hectares shown are those it shares with this fire
- 1,120 ha Nalae fire, March 2019 6,952 ha in total; the hectares shown are those it shares with this fire
- 315 ha Nalae fire, March 2023 2,370 ha in total; the hectares shown are those it shares with this fire
What happened to each town
-
Nalae where it started1,735 ha reached on 26 Mar1.0 %
-
767 ha reached on 2 Apr0.4 %
Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance is from the town centre to the nearest fire: staying a kilometre away does not mean it reached the houses.
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 6 April 2025 the air beside the fire reached 167 µg/m³ of PM2.5. That day averaged 115: 7.7 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 · 77Every 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 Nalae fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 26 March 2025 to 4 April 2025 (10 days). The perimeter dates it from 2 April 2025 to 4 April 2025.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 2,490 hectares (24.9 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire entered 2 municipalities: Nalae (1,735 ha, 1.0 %); Hoon (767 ha, 0.4 %).
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Laos (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
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
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.