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LA · Laos · –

Paksxong fire, February 2023 Paksxong, Sanamxay

Out · last detection 3 Mar 2023, 17:53 UTC

The fire started on 9 February 2023 in Paksxong, Laos, and satellites saw it burning for 23 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,235 hectares from heat detections, spread across 2 municipalities.

It is the 4th largest in Champasak since 2016 (of 13 with a page). Number 97 in Laos in 2023, of 239.

Burnt area
3,235ha
GWIS perimeter (Copernicus)
Duration
23days
9 Feb 2023 – 3 Mar 2023
Municipalities hit
2
districts
Started on
9 Feb
2023
Heat detections
237
in a single hotspot: 298 MW
Danger at start
16
Moderate · FWI index
Average daily power
222MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 9 Feb3 Mar
3 Mar 2023

How it evolved, day by day

10 Feb 2023 · 183 MW · 4 11 Feb 2023 · 665 MW · 8 12 Feb 2023 · 8 MW · 2 13 Feb 2023 · 101 MW · 3 16 Feb 2023 · 245 MW · 6 17 Feb 2023 · 52 MW · 5 18 Feb 2023 · 308 MW · 7 20 Feb 2023 · 54 MW · 10 21 Feb 2023 · 10 MW · 5 22 Feb 2023 · 225 MW · 8 23 Feb 2023 · 39 MW · 8 24 Feb 2023 · 1,701 MW · 98 25 Feb 2023 · 25 MW · 21 26 Feb 2023 · 34 MW · 4 27 Feb 2023 · 11 MW · 3 28 Feb 2023 · 358 MW · 6 1 Mar 2023 · 79 MW · 11 2 Mar 2023 · 68 MW · 13 3 Mar 2023 · 57 MW · 15
10 Feb 16 Feb 21 Feb 24 Feb 1 Mar

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

The weather it burned in

32°high
52km/h · peak gust
23%lowest humidity

It had gone 26 days without rain (1 mm or more) when it started.

This area had burned before

97% of the perimeter overlaps earlier fires recorded since 2016: 542 ha in 2016, 504 ha in 2017, 322 ha in 2019, 2,768 ha in 2020, 3,459 ha in 2021, 2,637 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 3,134 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 2% of the area of London (32 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. Paksxong where it started
    3,168 ha reached on 10 Feb
    0.9 %
  2. 85 ha reached on 11 Feb
    0.0 %

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 area1.1 ha
Residents≈ 250

Inside the perimeter there were about 1.1 hectares of built-up land and about 250 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)
9 Feb 31.0 °C 36 % 24 km/h 0.0 mm Moderate 16
10 Feb 31.5 °C 28 % 27 km/h 0.0 mm Moderate 19
11 Feb 30.7 °C 40 % 24 km/h 0.0 mm Moderate 19
12 Feb 31.8 °C 35 % 27 km/h 0.0 mm Moderate 20
13 Feb 31.8 °C 34 % 24 km/h 0.0 mm Moderate 20
14 Feb 28.3 °C 53 % 26 km/h 0.8 mm Moderate 12
15 Feb 26.0 °C 54 % 48 km/h 1.4 mm Low 9
16 Feb 26.7 °C 42 % 46 km/h 0.0 mm Moderate 17
17 Feb 28.7 °C 31 % 25 km/h 0.0 mm Moderate 19
18 Feb 29.9 °C 35 % 24 km/h 0.0 mm Moderate 19
19 Feb 27.6 °C 45 % 31 km/h 0.0 mm Moderate 20
20 Feb 28.2 °C 37 % 31 km/h 0.0 mm Moderate 20
21 Feb 29.2 °C 33 % 27 km/h 0.0 mm Moderate 20
22 Feb 29.0 °C 34 % 26 km/h 0.0 mm Moderate 20
23 Feb 30.1 °C 33 % 23 km/h 0.0 mm Moderate 20
24 Feb 30.0 °C 23 % 40 km/h 0.0 mm High 30
25 Feb 27.8 °C 35 % 49 km/h 0.0 mm High 32
26 Feb 25.8 °C 41 % 52 km/h 0.0 mm High 29
27 Feb 27.8 °C 38 % 33 km/h 0.0 mm High 24
28 Feb 30.3 °C 34 % 28 km/h 0.0 mm High 22
1 Mar 31.4 °C 35 % 23 km/h 0.0 mm High 22
2 Mar 29.4 °C 34 % 35 km/h 0.0 mm High 25
3 Mar 30.5 °C 26 % 26 km/h 0.0 mm High 26
4 Mar after 28.7 °C 33 % 36 km/h 0.0 mm High 29
5 Mar after 28.4 °C 32 % 34 km/h 0.0 mm High 29
6 Mar after 30.1 °C 25 % 26 km/h 0.0 mm High 27
7 Mar after 30.8 °C 28 % 26 km/h 0.0 mm High 26
8 Mar after 32.2 °C 26 % 26 km/h 0.0 mm High 27
9 Mar after 30.2 °C 32 % 32 km/h 0.0 mm High 30
10 Mar after 32.0 °C 28 % 23 km/h 0.0 mm High 27
11 Mar after 32.4 °C 29 % 24 km/h 0.0 mm High 27
12 Mar after 31.7 °C 27 % 33 km/h 0.0 mm High 31
13 Mar after 29.1 °C 34 % 42 km/h 0.0 mm High 34

Its twins: fires that started in the same weather

It started with an FWI of 15.5, a minimum humidity of 36% and 26 days without rain. Fires in the area that started in weather like this since 2016: 24.

FWI at the start 15.5
Minimum humidity 36 %
Days without rain 26
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Sanxay fire, April 2025
2,133 ha 4 days FWI 16.9 Min. humidity 36 % 73 km away, in 2025

First rain (1 mm or more) after it ended: 2.4 mm on 9 Apr.

What happened to them

15 days
median duration
2,107 ha
median area
100 %
went past 1,000 ha
2.5 mm
rain at the end (median; 17 of 24 had it)

It was 1.5 times larger than the median of its twins and lasted 23 days, against 15 days.

Only 5 of its 24 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 7 of 24, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 2.5 mm.

This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it

How it ended

—first rain
—no rain in ten days
52km/h · max. gust

It was considered over on 3 Mar, and not even 1 mm fell in the following ten days: it went out without rain. Twins with rain when they ended: 17 of 24, with a median of 2.5 mm.

Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

How a twin is chosen

  • Same area: fires that have already ended, less than 250 km from this one, since 2016.
  • Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
  • Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
  • Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
  • They are sorted by similarity, and the outlines of the first five are drawn.

How we calculate it

Before and after, from space

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

Before · 2 Feb 2023
After · 10 Mar 2023

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 19 February 2023 the air beside the fire reached 235 µg/m³ of PM2.5. That day averaged 116: 7.8 times the WHO daily guideline (15).

PM2.5 peak235 µg/m³
Days over the guideline25 days
PM10336 µg/m³
Optical depth1.60
7 Feb13 Feb19 Feb25 Feb3 Mar
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 · 237Every 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 Laos

Frequently asked questions

How long did the Paksxong fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 9 February 2023 to 3 March 2023 (23 days). The perimeter dates it from 16 February 2023 to 24 February 2023.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,235 hectares (32.4 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Paksxong (3,168 ha, 0.9 %); Sanamxay (85 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 31.8 °C, humidity dropped to 23 % and gusts hit 52 km/h. The fire danger index (FWI) reached 32, 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.
How did the fires that started in similar weather in this area end?
Fires less than 250 km away that started since 2016 with a similar FWI, humidity and dry spell: 24. Their median duration was 15 days and their median area 2,107 ha; 100 % went past 1,000 ha. Only 5 of its 24 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 7 of 24, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 2.5 mm.

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.

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.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 16 February 2023 to 24 February 2023. 237 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 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.