How long did the Chae Hom fire last?

According to the heat detections seen by satellite inside the perimeter, it burned from 21 March 2026 to 24 April 2026 (35 days). The perimeter dates it from 23 March 2026 to 20 April 2026.

How much area did it burn?

The perimeter GWIS (Copernicus) rebuilt from heat detections is 15,027 hectares (150.3 km²). It is an estimate: official national figures may differ.

Which municipalities burned?

The fire entered 3 municipalities: Ngao (10,080 ha, 6.7 %); Mueang Phayao (2,985 ha, 3.3 %); Wang Nuea (2,051 ha, 2.2 %).

What was the weather like?

During the fire the temperature reached 36.4 °C, humidity dropped to 19 % and gusts hit 44 km/h. The fire danger index (FWI) reached 44, 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.

TH · Thailand · 2026-03-21 → 2026-04-24

Chae Hom fire, 21 March 2026 แจ้ห่ม · Ngao, Mueang Phayao, Wang Nuea

Out · last detection 24 Apr 2026, 06:44 UTC

The fire started on 21 March 2026 in Chae Hom, Thailand, and satellites saw it burning for 35 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 15,027 hectares from heat detections, spread across 3 municipalities.

It is the 6th largest in Lampang Province since 2016 (of 216 with a page). Number 40 in Thailand in 2026, of 689.

Compare with…

Suggestions: Ngao · 2020 Ngao · 2016 Ngao · 2023 Ngao · 2019

Burnt area: 15,027ha; GWIS perimeter (Copernicus)
Duration: 35days; 21 Mar 2026 – 24 Apr 2026
Municipalities hit: 3; districts
Started on: 21 Mar; 2026
Heat detections: 443; in a single hotspot: 60 MW
Danger at start: 24; High · FWI index
Average daily power: 52MW; detected power per day, on average

HOTSPOTS BY DAY 21 Mar24 Apr

Play back 24 Apr 2026

How it evolved, day by day

21 Mar 26 Mar 31 Mar 5 Apr 10 Apr 15 Apr 20 Apr

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

44km/h · peak gust

19%lowest humidity

It had gone 3 days without rain (1 mm or more) when it started. Rain came after the fire: 4.0 mm on 25 Apr.

This area had burned before

69% of the perimeter overlaps earlier fires recorded since 2016: 4,914 ha in 2016, 9 ha in 2017, 459 ha in 2018, 4,217 ha in 2019, 3,041 ha in 2020, 2,290 ha in 2021, 1,623 ha in 2023, 2,791 ha in 2024, 614 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 10,382 ha that had burned before.

How big is it?

It burned the equivalent of 9.5% of the area of London (150 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

Ngao งาว

10,080 ha reached on 23 Mar

6.7 %
Mueang Phayao เมืองพะเยา

2,985 ha reached on 26 Mar

3.3 %
Wang Nuea วังเหนือ

2,051 ha reached on 21 Mar

2.2 %

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 area4.2 ha

Residents≈ 400

Inside the perimeter there were about 4.2 hectares of built-up land and about 400 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)
21 Mar	33.1 °C	34 %	34 km/h	0.2 mm	High 24
22 Mar	32.3 °C	30 %	41 km/h	0.0 mm	High 27
23 Mar	33.3 °C	22 %	36 km/h	0.0 mm	High 30
24 Mar	33.7 °C	21 %	33 km/h	0.0 mm	High 31
25 Mar	33.7 °C	21 %	37 km/h	0.0 mm	High 33
26 Mar	34.2 °C	20 %	31 km/h	0.0 mm	High 33
27 Mar	34.4 °C	20 %	39 km/h	0.0 mm	High 36
28 Mar	34.7 °C	24 %	40 km/h	0.0 mm	High 37
29 Mar	34.3 °C	23 %	44 km/h	0.0 mm	Very high 39
30 Mar	34.2 °C	25 %	36 km/h	0.0 mm	High 37
31 Mar	34.7 °C	27 %	32 km/h	0.0 mm	High 36
1 Apr	34.7 °C	31 %	29 km/h	0.0 mm	High 33
2 Apr	35.2 °C	27 %	35 km/h	0.0 mm	High 35
3 Apr	35.4 °C	27 %	27 km/h	0.0 mm	High 34
4 Apr	34.1 °C	33 %	30 km/h	0.0 mm	High 32
5 Apr	35.4 °C	33 %	30 km/h	0.0 mm	High 34
6 Apr	34.8 °C	33 %	27 km/h	0.0 mm	High 34
7 Apr	34.6 °C	33 %	32 km/h	0.0 mm	High 35
8 Apr	35.6 °C	23 %	37 km/h	0.0 mm	Very high 38
9 Apr	34.8 °C	25 %	34 km/h	0.0 mm	High 37
10 Apr	35.4 °C	24 %	40 km/h	0.0 mm	Very high 40
11 Apr	34.6 °C	28 %	36 km/h	0.0 mm	Very high 38
12 Apr	35.4 °C	20 %	26 km/h	0.0 mm	High 37
13 Apr	35.5 °C	28 %	28 km/h	0.0 mm	Very high 38
14 Apr	35.7 °C	27 %	30 km/h	0.0 mm	Very high 38
15 Apr	36.4 °C	19 %	40 km/h	0.0 mm	Very high 44
16 Apr	35.5 °C	26 %	27 km/h	0.0 mm	Very high 38
17 Apr	35.2 °C	29 %	18 km/h	0.0 mm	High 36
18 Apr	34.8 °C	32 %	27 km/h	0.0 mm	High 36
19 Apr	35.6 °C	26 %	35 km/h	0.0 mm	Very high 38
20 Apr	34.1 °C	35 %	33 km/h	0.0 mm	High 34
21 Apr	35.2 °C	34 %	32 km/h	0.1 mm	High 35
22 Apr	35.2 °C	36 %	30 km/h	0.0 mm	High 34
23 Apr	33.3 °C	40 %	29 km/h	0.3 mm	High 31
24 Apr	34.0 °C	41 %	29 km/h	0.3 mm	High 30
25 Apr after	26.3 °C	70 %	30 km/h	4.0 mm	Very low 4

Before and after, from space

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

↔

Before · 14 Mar 2026

After · 1 May 2026

Before After

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 guideline34 days

PM10171 µg/m³

Optical depth2.08

WHO 15

21222324252627282930311234567891011121314151617181920212223

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 · 443Every 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 time	Satellite	FRP (MW)	Lat	Lon

Other fires nearby

All fires in Thailand ›

Frequently asked questions

How long did the Chae Hom fire last?: According to the heat detections seen by satellite inside the perimeter, it burned from 21 March 2026 to 24 April 2026 (35 days). The perimeter dates it from 23 March 2026 to 20 April 2026.
How much area did it burn?: The perimeter GWIS (Copernicus) rebuilt from heat detections is 15,027 hectares (150.3 km²). It is an estimate: official national figures may differ.
Which municipalities burned?: The fire entered 3 municipalities: Ngao (10,080 ha, 6.7 %); Mueang Phayao (2,985 ha, 3.3 %); Wang Nuea (2,051 ha, 2.2 %).
What was the weather like?: During the fire the temperature reached 36.4 °C, humidity dropped to 19 % and gusts hit 44 km/h. The fire danger index (FWI) reached 44, 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

NASA FIRMS ↗
GWIS · Copernicus ↗

History of this page · 2 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.

26 October 2026 Last day with fire: 20 April 2026 → 24 April 2026.
26 October 2026 Start date: 23 March 2026 → 21 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?

Dates or duration Place or towns Burned area Name It was not a wildfire Same fire as another page Something else

What really happened?

Your connection to the fire (optional) Email (optional)

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.

How we know this

Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 5 polygons grouped in this page.
Dates adjusted with the VIIRS detections inside the perimeter, which said 23 March 2026 to 20 April 2026. 443 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.

Where it burned