Xay fire, 23 March 2026 Xay
The fire started on 23 March 2026 in Xay, Laos, and satellites saw it burning for 24 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 5,900 hectares from heat detections, spread across a single municipality.
It is the 44th largest in Oudomxay since 2016 (of 241 with a page). Number 69 in Laos in 2026, of 287.
- Burnt area
- 5,900ha
- GWIS perimeter (Copernicus)
- Duration
- 24days
- 23 Mar 2026 – 15 Apr 2026
- Municipalities hit
- 1
- districts
- Started on
- 23 Mar
- 2026
- Heat detections
- 229
- in a single hotspot: 365 MW
- Danger at start
- 5
- Very low · FWI index
- Energy released
- 7.8GW
- 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.
The weather it burned in
It had gone 0 days without rain (1 mm or more) when it started. Rain came after the fire: 7.4 mm on 19 Apr.
This area had burned before
82% of the perimeter overlaps earlier fires recorded since 2016: 1,713 ha in 2017, 6 ha in 2019, 2,369 ha in 2020, 2,122 ha in 2021, 1,949 ha in 2023, 659 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 4,848 ha that had burned before.
- 1,949 ha Xay fire, March 2023 3,109 ha in total; the hectares shown are those it shares with this fire
- 1,646 ha Xay fire, April 2017 2,018 ha in total; the hectares shown are those it shares with this fire
- 287 ha Xay fire, March 2024 4,036 ha in total; the hectares shown are those it shares with this fire
- 67 ha Nambak fire, April 2017 3,696 ha in total; the hectares shown are those it shares with this fire
What happened to each town
-
Xay where it started5,927 ha reached on 23 Mar2.8 %
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.
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) |
|---|---|---|---|---|---|
| 23 Mar | 30.8 °C | 36 % | 34 km/h | 0.2 mm | Very low 5 |
| 24 Mar | 31.4 °C | 34 % | 31 km/h | 0.0 mm | Low 10 |
| 25 Mar | 31.2 °C | 34 % | 39 km/h | 0.0 mm | Moderate 12 |
| 26 Mar | 32.0 °C | 31 % | 38 km/h | 0.0 mm | Moderate 14 |
| 27 Mar | 31.6 °C | 34 % | 40 km/h | 0.0 mm | Moderate 15 |
| 28 Mar | 32.9 °C | 29 % | 38 km/h | 0.0 mm | Moderate 17 |
| 29 Mar | 30.9 °C | 34 % | 49 km/h | 1.0 mm | Moderate 14 |
| 30 Mar | 31.9 °C | 34 % | 45 km/h | 0.0 mm | Moderate 16 |
| 31 Mar | 31.7 °C | 36 % | 39 km/h | 0.2 mm | Moderate 16 |
| 1 Apr | 31.5 °C | 40 % | 29 km/h | 0.0 mm | Moderate 16 |
| 2 Apr | 31.6 °C | 41 % | 44 km/h | 0.0 mm | Moderate 18 |
| 3 Apr | 33.9 °C | 31 % | 40 km/h | 0.0 mm | Moderate 21 |
| 4 Apr | 33.3 °C | 33 % | 37 km/h | 0.0 mm | Moderate 21 |
| 5 Apr | 32.6 °C | 37 % | 45 km/h | 0.0 mm | High 24 |
| 6 Apr | 33.2 °C | 37 % | 39 km/h | 0.0 mm | High 22 |
| 7 Apr | 33.0 °C | 41 % | 36 km/h | 0.1 mm | High 22 |
| 8 Apr | 32.6 °C | 40 % | 37 km/h | 0.5 mm | High 23 |
| 9 Apr | 32.7 °C | 33 % | 45 km/h | 0.0 mm | High 25 |
| 10 Apr | 32.0 °C | 33 % | 47 km/h | 0.0 mm | High 26 |
| 11 Apr | 32.3 °C | 33 % | 48 km/h | 0.0 mm | High 27 |
| 12 Apr | 33.6 °C | 24 % | 34 km/h | 0.0 mm | High 28 |
| 13 Apr | 34.4 °C | 28 % | 33 km/h | 0.0 mm | High 28 |
| 14 Apr | 33.4 °C | 34 % | 33 km/h | 0.0 mm | High 28 |
| 15 Apr | 32.6 °C | 37 % | 36 km/h | 0.0 mm | High 28 |
| 16 Apr after | 33.2 °C | 33 % | 30 km/h | 0.0 mm | High 26 |
| 17 Apr after | 33.3 °C | 37 % | 28 km/h | 0.0 mm | High 27 |
| 18 Apr after | 30.3 °C | 44 % | 29 km/h | 0.0 mm | High 22 |
| 19 Apr after | 27.4 °C | 67 % | 36 km/h | 7.4 mm | Very low 1 |
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 18 April 2026 the air beside the fire reached 216 µg/m³ of PM2.5. That day averaged 161: 11 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 · 229Every 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 Xay fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 23 March 2026 to 15 April 2026 (24 days). The perimeter dates it from 25 March 2026 to 11 April 2026.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 5,900 hectares (59.0 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Xay (5,927 ha, 2.8 %).
- What was the weather like?
- During the fire the temperature reached 34.4 °C, humidity dropped to 24 % and gusts hit 49 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 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.