How long did the Pong fire last?

According to the heat detections seen by satellite inside the perimeter, it burned from 29 March 2026 to 21 April 2026 (24 days). The perimeter dates it from 4 April 2026 to 21 April 2026.

How much area did it burn?

The perimeter GWIS (Copernicus) rebuilt from heat detections is 5,089 hectares (50.9 km²). It is an estimate: official national figures may differ.

Which municipalities burned?

The fire only entered Pong (5,117 ha, 3.0 %).

What was the weather like?

During the fire the temperature reached 37.4 °C, humidity dropped to 21 % and gusts hit 41 km/h. The fire danger index (FWI) reached 40, 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 · 2026-03-29 → 2026-04-21

Pong fire, 29 March 2026 ปง · Pong

Out · last detection 21 Apr 2026, 06:00 UTC

The fire started on 29 March 2026 in Pong, Thailand, and satellites saw it burning for 24 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 5,089 hectares from heat detections, spread across a single municipality.

It is the 6th largest in Phayao Province since 2016 (of 111 with a page). Number 116 in Thailand in 2026, of 689.

The power measured by the satellite is low (22.7 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Compare with…

Suggestions: Pong · 2016 Pong · 2019 Pong · 2023 Pong · 2023

Burnt area: 5,089ha; GWIS perimeter (Copernicus)
Duration: 24days; 29 Mar 2026 – 21 Apr 2026
Municipalities hit: 1; districts
Started on: 29 Mar; 2026
Heat detections: 142; in a single hotspot: 23 MW
Danger at start: 32; High · FWI index
Average daily power: 33MW; detected power per day, on average

HOTSPOTS BY DAY 29 Mar21 Apr

Play back 21 Apr 2026

How it evolved, day by day

29 Mar 5 Apr 10 Apr 13 Apr 16 Apr 19 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

37°high

41km/h · peak gust

21%lowest humidity

It had gone 15 days without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 23 Apr.

This area had burned before

93% of the perimeter overlaps earlier fires recorded since 2016: 2,995 ha in 2016, 359 ha in 2018, 3,305 ha in 2019, 1,538 ha in 2020, 96 ha in 2021, 3,709 ha in 2023, 844 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 4,708 ha that had burned before.

How big is it?

It burned the equivalent of 3.2% of the area of London (51 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

Pong ปง where it started

5,117 ha reached on 29 Mar

3.0 %

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.

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)
29 Mar	35.4 °C	23 %	41 km/h	0.1 mm	High 32
30 Mar	35.2 °C	25 %	32 km/h	0.0 mm	High 30
31 Mar	35.2 °C	28 %	31 km/h	0.0 mm	High 30
1 Apr	35.1 °C	32 %	23 km/h	0.0 mm	High 26
2 Apr	35.9 °C	29 %	30 km/h	0.0 mm	High 30
3 Apr	35.9 °C	29 %	28 km/h	0.0 mm	High 29
4 Apr	34.7 °C	33 %	27 km/h	0.0 mm	High 29
5 Apr	35.5 °C	34 %	30 km/h	0.0 mm	High 30
6 Apr	35.5 °C	34 %	27 km/h	0.0 mm	High 28
7 Apr	35.3 °C	38 %	29 km/h	0.0 mm	High 28
8 Apr	35.8 °C	28 %	27 km/h	0.0 mm	High 29
9 Apr	35.6 °C	27 %	31 km/h	0.0 mm	High 30
10 Apr	36.3 °C	23 %	35 km/h	0.0 mm	High 36
11 Apr	35.5 °C	26 %	36 km/h	0.0 mm	High 36
12 Apr	35.9 °C	21 %	26 km/h	0.0 mm	High 33
13 Apr	36.2 °C	28 %	26 km/h	0.0 mm	High 33
14 Apr	36.8 °C	28 %	25 km/h	0.0 mm	High 34
15 Apr	37.4 °C	21 %	34 km/h	0.0 mm	Very high 40
16 Apr	36.8 °C	21 %	28 km/h	0.0 mm	High 37
17 Apr	35.4 °C	31 %	23 km/h	0.0 mm	High 33
18 Apr	35.3 °C	36 %	28 km/h	0.0 mm	High 34
19 Apr	36.1 °C	28 %	31 km/h	0.0 mm	High 34
20 Apr	34.0 °C	39 %	35 km/h	0.0 mm	High 32
21 Apr	36.0 °C	32 %	32 km/h	0.0 mm	High 32
22 Apr after	36.4 °C	35 %	33 km/h	0.0 mm	High 32
23 Apr after	33.8 °C	39 %	32 km/h	1.0 mm	High 22

Before and after, from space

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

↔

Before · 22 Mar 2026

After · 28 Apr 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 17 April 2026 the air beside the fire reached 246 µg/m³ of PM2.5. That day averaged 181: 12 times the WHO daily guideline (15).

PM2.5 peak246 µg/m³

Days over the guideline29 days

PM10282 µg/m³

Optical depth2.38

WHO 15

2728293031123456789101112131415161718192021222324

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 · 142Every 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 Pong fire last?: According to the heat detections seen by satellite inside the perimeter, it burned from 29 March 2026 to 21 April 2026 (24 days). The perimeter dates it from 4 April 2026 to 21 April 2026.
How much area did it burn?: The perimeter GWIS (Copernicus) rebuilt from heat detections is 5,089 hectares (50.9 km²). It is an estimate: official national figures may differ.
Which municipalities burned?: The fire only entered Pong (5,117 ha, 3.0 %).
What was the weather like?: During the fire the temperature reached 37.4 °C, humidity dropped to 21 % and gusts hit 41 km/h. The fire danger index (FWI) reached 40, 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 · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.

26 October 2026 Start date: 4 April 2026 → 29 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.
Dates adjusted with the VIIRS detections inside the perimeter, which said 4 April 2026 to 21 April 2026. 142 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.

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