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Chun fire, April 2026 Chun, Dok Khamtai, Pong

Out · last detection 15 Apr 2026, 18:43 UTC

The fire started on 1 April 2026 in Chun, Thailand, and satellites saw it burning for 16 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,583 hectares from heat detections, spread across 3 municipalities.

It is the 18th largest in Phayao Province since 2016 (of 125 with a page). Number 200 in Thailand in 2026, of 880.

The power measured by the satellite is low (15.2 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Burnt area
3,583ha
GWIS perimeter (Copernicus)
Duration
16days
1 Apr 2026 – 16 Apr 2026
Municipalities hit
3
districts
Started on
1 Apr
2026
Heat detections
87
in a single hotspot: 15 MW
Danger at start
28
High · FWI index
Energy released
207MW
sum of detected power

Where it burned

15 Apr 2026
HOTSPOTS BY DAY 1 Apr16 Apr

How it evolved, day by day

347891012131415

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

The weather it burned in

36°high
39km/h · peak gust
21%lowest humidity

It had gone 8 days without rain (1 mm or more) when it started. Rain came after the fire: 3.1 mm on 25 Apr.

This area had burned before

74% of the perimeter overlaps earlier fires recorded since 2016: 166 ha in 2016, 70 ha in 2017, 95 ha in 2018, 1,659 ha in 2019, 1,752 ha in 2020, 634 ha in 2021, 456 ha in 2023, 743 ha in 2024, 923 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 2,650 ha that had burned before.

What happened to each town

  1. Chun where it started
    1,808 ha reached on 28 Mar
    3.4 %
  2. Dok Khamtai
    1,786 ha reached on 26 Mar
    2.4 %
  3. Pong
    7 ha reached on 8 Apr
    0.0 %

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)
22 Mar 33.0 °C 27 % 39 km/h 0.0 mm High 28
23 Mar 33.9 °C 22 % 30 km/h 0.0 mm High 28
24 Mar 34.1 °C 22 % 23 km/h 0.0 mm High 28
25 Mar 34.1 °C 21 % 30 km/h 0.0 mm High 31
26 Mar 34.2 °C 23 % 23 km/h 0.0 mm High 28
27 Mar 34.6 °C 23 % 31 km/h 0.0 mm High 32
28 Mar 34.8 °C 25 % 33 km/h 0.0 mm High 34
29 Mar 34.6 °C 23 % 39 km/h 0.0 mm High 36
30 Mar 34.1 °C 27 % 28 km/h 0.0 mm High 33
31 Mar 34.5 °C 30 % 27 km/h 0.0 mm High 31
1 Apr 34.3 °C 34 % 23 km/h 0.0 mm High 29
2 Apr 35.0 °C 30 % 28 km/h 0.0 mm High 31
3 Apr 35.1 °C 30 % 25 km/h 0.0 mm High 31
4 Apr 33.9 °C 36 % 24 km/h 0.0 mm High 29
5 Apr 35.0 °C 35 % 24 km/h 0.0 mm High 30
6 Apr 34.5 °C 36 % 24 km/h 0.0 mm High 30
7 Apr 34.4 °C 37 % 26 km/h 0.0 mm High 30
8 Apr 35.1 °C 28 % 27 km/h 0.0 mm High 32
9 Apr 34.5 °C 30 % 24 km/h 0.0 mm High 31
10 Apr 35.0 °C 26 % 33 km/h 0.0 mm High 36
11 Apr 34.4 °C 29 % 32 km/h 0.0 mm High 34
12 Apr 34.8 °C 24 % 21 km/h 0.0 mm High 34
13 Apr 35.1 °C 31 % 24 km/h 0.0 mm High 34
14 Apr 35.5 °C 31 % 24 km/h 0.0 mm High 34
15 Apr 36.0 °C 23 % 32 km/h 0.0 mm Very high 39
16 Apr 34.9 °C 28 % 21 km/h 0.0 mm High 35
17 Apr after 34.6 °C 33 % 18 km/h 0.0 mm High 34
18 Apr after 34.2 °C 37 % 23 km/h 0.0 mm High 32
19 Apr after 34.9 °C 31 % 29 km/h 0.1 mm High 33
20 Apr after 33.5 °C 38 % 33 km/h 0.0 mm High 33
21 Apr after 34.9 °C 36 % 32 km/h 0.0 mm High 33
22 Apr after 35.2 °C 37 % 30 km/h 0.0 mm High 33
23 Apr after 32.8 °C 43 % 29 km/h 0.5 mm High 29
24 Apr after 34.4 °C 37 % 31 km/h 0.1 mm High 30
25 Apr after 27.1 °C 66 % 33 km/h 3.1 mm Low 6

Before and after, from space

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

Before · 25 Mar 2026
After · 23 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 18 April 2026 the air beside the fire reached 136 µg/m³ of PM2.5. That day averaged 109: 7.3 times the WHO daily guideline (15).

PM2.5 peak136 µg/m³
Days over the guideline21 days
PM10171 µg/m³
Optical depth2.08
303112345678910111213141516171819
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 · 87Every 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 Thailand ›

Frequently asked questions

How long did the Chun fire last?
GWIS (Copernicus) dates it between 1 April 2026 and 16 April 2026: 16 days between the first and last heat detection of the perimeter.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,583 hectares (35.8 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 3 municipalities: Chun (1,808 ha, 3.4 %); Dok Khamtai (1,786 ha, 2.4 %); Pong (7 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 36.0 °C, humidity dropped to 21 % and gusts hit 39 km/h. The fire danger index (FWI) reached 39, class Very high.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Thailand (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: 199 · 191

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
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 199 · 191.

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.