Phaxay fire, March 2023 Anouvong, Longcheng, Phaxay
The fire started on 15 March 2023 in Phaxay, Laos, and satellites saw it burning for 22 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 8,559 hectares from heat detections, spread across 3 municipalities.
It is the 13th largest in Xiangkhouang since 2016 (of 107 with a page). Number 29 in Laos in 2023, of 214.
- Burnt area
- 8,559ha
- GWIS perimeter (Copernicus)
- Duration
- 22days
- 15 Mar 2023 – 5 Apr 2023
- Municipalities hit
- 3
- districts
- Started on
- 15 Mar
- 2023
- Heat detections
- 353
- in a single hotspot: 276 MW
- Danger at start
- 7
- Low · FWI index
- Energy released
- 5.9GW
- 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 one day without rain (1 mm or more) when it started. Rain came after the fire: 6.8 mm on 8 Apr.
This area had burned before
16% of the perimeter overlaps earlier fires recorded since 2016: 8 ha in 2017, 53 ha in 2018, 53 ha in 2019, 1,273 ha in 2022.
What happened to each town
-
3,785 ha reached on 18 Mar1.8 %
-
2,485 ha reached on 15 Mar1.3 %
-
Phaxay where it started2,336 ha reached on 15 Mar2.4 %
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.
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) |
|---|---|---|---|---|---|
| 15 Mar | 30.2 °C | 43 % | 19 km/h | 0.2 mm | Low 7 |
| 16 Mar | 27.7 °C | 56 % | 24 km/h | 1.3 mm | Very low 4 |
| 17 Mar | 30.0 °C | 54 % | 24 km/h | 1.8 mm | Very low 3 |
| 18 Mar | 30.8 °C | 55 % | 27 km/h | 1.6 mm | Very low 4 |
| 19 Mar | 30.7 °C | 57 % | 37 km/h | 1.2 mm | Very low 5 |
| 20 Mar | 32.8 °C | 41 % | 43 km/h | 0.3 mm | Moderate 13 |
| 21 Mar | 32.4 °C | 47 % | 49 km/h | 0.4 mm | Moderate 15 |
| 22 Mar | 34.2 °C | 30 % | 52 km/h | 0.0 mm | High 23 |
| 23 Mar | 33.8 °C | 31 % | 51 km/h | 0.5 mm | High 23 |
| 24 Mar | 34.8 °C | 31 % | 46 km/h | 0.1 mm | High 23 |
| 25 Mar | 34.5 °C | 30 % | 46 km/h | 0.0 mm | High 24 |
| 26 Mar | 33.1 °C | 35 % | 41 km/h | 0.0 mm | High 24 |
| 27 Mar | 30.6 °C | 52 % | 34 km/h | 0.8 mm | Moderate 13 |
| 28 Mar | 28.6 °C | 69 % | 43 km/h | 1.3 mm | Low 6 |
| 29 Mar | 28.1 °C | 79 % | 41 km/h | 2.5 mm | Very low 1 |
| 30 Mar | 29.1 °C | 62 % | 37 km/h | 2.3 mm | Very low 2 |
| 31 Mar | 29.9 °C | 58 % | 38 km/h | 0.9 mm | Very low 5 |
| 1 Apr | 30.8 °C | 56 % | 37 km/h | 1.2 mm | Low 6 |
| 2 Apr | 32.8 °C | 40 % | 45 km/h | 0.2 mm | Moderate 16 |
| 3 Apr | 32.4 °C | 38 % | 52 km/h | 0.0 mm | Moderate 21 |
| 4 Apr | 34.1 °C | 31 % | 46 km/h | 0.0 mm | High 24 |
| 5 Apr | 33.9 °C | 32 % | 40 km/h | 0.0 mm | High 24 |
| 6 Apr after | 33.9 °C | 36 % | 31 km/h | 0.0 mm | High 24 |
| 7 Apr after | 31.4 °C | 50 % | 35 km/h | 0.0 mm | Moderate 20 |
| 8 Apr after | 29.0 °C | 66 % | 29 km/h | 6.8 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.
Detections table · 353Every 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 Phaxay fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 15 March 2023 to 5 April 2023 (22 days). The perimeter dates it from 20 March 2023 to 29 March 2023.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 8,559 hectares (85.6 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire entered 3 municipalities: Anouvong (3,785 ha, 1.8 %); Longcheng (2,485 ha, 1.3 %); Phaxay (2,336 ha, 2.4 %).
- What was the weather like?
- During the fire the temperature reached 34.8 °C, humidity dropped to 30 % and gusts hit 52 km/h. The fire danger index (FWI) reached 24, 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.