Pak Chom fire, 8 April 2026 ปากชม · Na Yung, Pak Chom, Sangkhom
The fire started on 8 April 2026 in Pak Chom, Thailand, and satellites saw it burning for 15 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 37,269 hectares from heat detections, spread across 3 municipalities.
It is the largest fire in Loei Province since 2016 (of 113 with a page). Number 14 in Thailand in 2026, of 689.
Compare with…
- Burnt area
- 37,269ha
- GWIS perimeter (Copernicus)
- Duration
- 15days
- 8 Apr 2026 – 22 Apr 2026
- Municipalities hit
- 3
- districts
- Started on
- 8 Apr
- 2026
- Heat detections
- 1,264
- in a single hotspot: 90 MW
- Danger at start
- 30
- High · FWI index
- Average daily power
- 628MW
- detected power per day, on average
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 9 days without rain (1 mm or more) when it started. Rain came after the fire: 11.2 mm on 23 Apr.
This area had burned before
87% of the perimeter overlaps earlier fires recorded since 2016: 12,457 ha in 2016, 1,340 ha in 2017, 5,347 ha in 2018, 18,611 ha in 2019, 6,479 ha in 2020, 17,657 ha in 2023, 5,147 ha in 2024, 5,636 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 32,339 ha that had burned before.
- 4,895 ha Na Yung fire, March 2023 4,939 ha in total; the hectares shown are those it shares with this fire
- 3,745 ha Na Yung fire, March 2019 3,824 ha in total; the hectares shown are those it shares with this fire
- 3,549 ha Sangkhom fire, March 2025 3,627 ha in total; the hectares shown are those it shares with this fire
- 2,829 ha Na Yung fire, March 2023 2,848 ha in total; the hectares shown are those it shares with this fire
- 1,863 ha Pak Chom fire, March 2019 2,110 ha in total; the hectares shown are those it shares with this fire
- 1,656 ha Na Yung fire, March 2019 2,152 ha in total; the hectares shown are those it shares with this fire
- 1,491 ha Pak Chom fire, March 2016 6,354 ha in total; the hectares shown are those it shares with this fire
- 1,486 ha Na Yung fire, April 2018 1,561 ha in total; the hectares shown are those it shares with this fire
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Bangkok boundary: geoBoundaries · OpenStreetMap, Wambacher · © OpenStreetMap contributors (ODbL 1.0).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
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 2025Inside the perimeter there were about 5.9 hectares of built-up land and about 350 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) |
|---|---|---|---|---|---|
| 8 Apr | 36.7 °C | 24 % | 24 km/h | 0.0 mm | High 30 |
| 9 Apr | 36.5 °C | 23 % | 32 km/h | 0.0 mm | High 34 |
| 10 Apr | 36.9 °C | 22 % | 37 km/h | 0.0 mm | High 38 |
| 11 Apr | 36.3 °C | 28 % | 41 km/h | 0.0 mm | Very high 40 |
| 12 Apr | 36.7 °C | 26 % | 29 km/h | 0.0 mm | High 36 |
| 13 Apr | 37.4 °C | 25 % | 24 km/h | 0.0 mm | High 34 |
| 14 Apr | 37.8 °C | 24 % | 22 km/h | 0.0 mm | High 34 |
| 15 Apr | 38.2 °C | 18 % | 28 km/h | 0.0 mm | Very high 40 |
| 16 Apr | 38.0 °C | 21 % | 23 km/h | 0.0 mm | Very high 39 |
| 17 Apr | 37.7 °C | 18 % | 29 km/h | 0.0 mm | Very high 42 |
| 18 Apr | 33.6 °C | 46 % | 32 km/h | 2.8 mm | Moderate 12 |
| 19 Apr | 33.0 °C | 50 % | 35 km/h | 5.7 mm | Low 6 |
| 20 Apr | 33.7 °C | 44 % | 54 km/h | 0.7 mm | High 22 |
| 21 Apr | 35.0 °C | 40 % | 23 km/h | 0.4 mm | Moderate 19 |
| 22 Apr | 36.0 °C | 34 % | 32 km/h | 0.0 mm | High 26 |
| 23 Apr after | 33.9 °C | 47 % | 32 km/h | 11.2 mm | Very low 4 |
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 17 April 2026 the air beside the fire reached 267 µg/m³ of PM2.5. That day averaged 150: 10.0 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 · 1,264Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 6,354 haPak Chom ปากชม16 March 2016 · 8 days · 15 km away
- 6,382 haSangkhom สังคมMarch 2026 · 16 days · 17 km away
- 6,827 haMeunMarch 2026 · 22 days · 32 km away
- 23,048 haNaxaithongApril 2026 · 18 days · 35 km away
- 12,599 haNaxaithongMarch 2023 · 10 days · 36 km away
- 10,355 haSangthongMarch 2020 · 8 days · 36 km away
Frequently asked questions
- How long did the Pak Chom fire last?
- GWIS (Copernicus) dates it between 8 April 2026 and 22 April 2026: 15 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 37,269 hectares (372.7 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire entered 3 municipalities: Na Yung (18,294 ha, 36 %); Pak Chom (13,938 ha, 14 %); Sangkhom (5,250 ha, 11 %).
- What was the weather like?
- During the fire the temperature reached 38.2 °C, humidity dropped to 18 % and gusts hit 54 km/h. The fire danger index (FWI) reached 42, 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 · Emergency number and official warnings ›
Satellite cross-check
History of this page Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
No changes 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.
Report an error
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
- Dates from the perimeter: the VIIRS detections inside it did not change them. 1,264 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.
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.