Skip to content
worldfires
CN · China · →

Lanxi County fire, 20 March 2026 兰西县 · Lanxi County

Out · last detection 1 Apr 2026, 05:41 UTC

The fire started on 20 March 2026 in Lanxi County, China, and satellites saw it burning for 12 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,215 hectares from heat detections, spread across a single municipality.

It is the 1360th largest in Heilongjiang Province since 2016 (of 1841 with a page). Number 743 in China in 2026, of 972.

Compare with…
Burnt area
1,215ha
GWIS perimeter (Copernicus)
Duration
12days
20 Mar 2026 – 31 Mar 2026
Municipalities hit
1
counties
Started on
20 Mar
2026
Heat detections
66
in a single hotspot: 32 MW
Danger at start
5
Low · FWI index
Average daily power
75MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 20 Mar31 Mar
1 Apr 2026

How it evolved, day by day

20 Mar 2026 · 8 MW · 2 21 Mar 2026 · 5 MW · 1 22 Mar 2026 · 3 MW · 1 23 Mar 2026 · 15 MW · 1 24 Mar 2026 · 413 MW · 38 27 Mar 2026 · 2 MW · 1 31 Mar 2026 · 90 MW · 16 1 Apr 2026 · 60 MW · 6
20 Mar 22 Mar 24 Mar 31 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

17°high
54km/h · peak gust
17%lowest humidity

It had gone 16 days without rain (1 mm or more) when it started. Rain came after the fire: 1.1 mm on 29 Mar.

This area had burned before

61% of the perimeter overlaps earlier fires recorded since 2016: 343 ha in 2020, 598 ha in 2021. Part of it burned more than once, so the yearly figures add up to more than the 737 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 0.8% of the area of London (12 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. Lanxi County 兰西县 where it started
    1,210 ha reached on 20 Mar
    0.5 %

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 area17 ha
Residents≈ 1,100

Inside the perimeter there were about 17 hectares of built-up land and about 1,100 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)
20 Mar 2.4 °C 32 % 39 km/h 0.0 mm Low 5
21 Mar 10.5 °C 20 % 34 km/h 0.0 mm Low 6
22 Mar 11.1 °C 24 % 39 km/h 0.0 mm Low 7
23 Mar 11.8 °C 18 % 30 km/h 0.0 mm Low 7
24 Mar 16.6 °C 17 % 54 km/h 0.0 mm Moderate 14
25 Mar 14.9 °C 31 % 40 km/h 0.0 mm Low 10
26 Mar 13.4 °C 23 % 32 km/h 0.0 mm Low 10
27 Mar 11.3 °C 27 % 32 km/h 0.0 mm Low 10
28 Mar 13.2 °C 20 % 27 km/h 0.0 mm Low 9
29 Mar 10.6 °C 35 % 59 km/h 1.1 mm Low 8

Before and after, from space

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

Before · 13 Mar 2026
After · 7 Apr 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 23 March 2026 the air beside the fire reached 162 µg/m³ of PM2.5. That day averaged 105: 7.0 times the WHO daily guideline (15).

PM2.5 peak162 µg/m³
Days over the guideline10 days
PM10182 µg/m³
Optical depth1.29
18192021222324252627
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 · 66Every 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 China ›

Frequently asked questions

How long did the Lanxi County fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 20 March 2026 to 31 March 2026 (12 days). The perimeter dates it from 20 March 2026 to 24 March 2026.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,215 hectares (12.2 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Lanxi County (1,210 ha, 0.5 %).
What was the weather like?
During the fire the temperature reached 16.6 °C, humidity dropped to 17 % and gusts hit 54 km/h. The fire danger index (FWI) reached 14, class Moderate.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of China (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.

Emergency number: 119 · Emergency number and official warnings ›

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: 24 March 2026 → 31 March 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.

Report an error
What do you think is wrong?

We will only use your email to reply about this report. Privacy. This is not an emergency service: if there is a fire now, call 119.

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 20 March 2026 to 24 March 2026. 66 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 ADM3 (Open Data Commons Open Database License 1.0). 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.