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Pong fire, 2 April 2026 Pong, Chiang Muan, Mueang Nan

Out · last detection 21 Apr 2026, 18:31 UTC

The fire started on 2 April 2026 in Pong, Thailand, and satellites saw it burning for 20 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 15,350 hectares from heat detections, spread across 3 municipalities.

It is the largest fire in Phayao Province since 2016 (of 125 with a page). Number 44 in Thailand in 2026, of 880.

The power measured by the satellite is low (28.4 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
15,350ha
GWIS perimeter (Copernicus)
Duration
20days
2 Apr 2026 – 21 Apr 2026
Municipalities hit
3
districts
Started on
2 Apr
2026
Heat detections
411
in a single hotspot: 28 MW
Danger at start
31
High · FWI index
Energy released
1.6GW
sum of detected power

Where it burned

21 Apr 2026
HOTSPOTS BY DAY 2 Apr21 Apr

How it evolved, day by day

356789101112131415161718192021

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

The weather it burned in

40°high
44km/h · peak gust
19%lowest humidity

It had gone 2 days without rain (1 mm or more) when it started. Rain came after the fire: 12.4 mm on 24 Apr.

This area had burned before

83% of the perimeter overlaps earlier fires recorded since 2016: 6,336 ha in 2016, 1,762 ha in 2017, 1,616 ha in 2018, 8,469 ha in 2019, 2,715 ha in 2020, 1,130 ha in 2021, 680 ha in 2022, 4,911 ha in 2023, 1,100 ha in 2024, 5,201 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 12,758 ha that had burned before.

What happened to each town

  1. Pong where it started
    14,818 ha reached on 27 Mar
    8.7 %
  2. Chiang Muan
    490 ha reached on 14 Apr
    0.7 %
  3. Mueang Nan
    115 ha reached on 14 Apr
    0.1 %

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)
24 Mar 37.4 °C 22 % 30 km/h 0.0 mm High 31
25 Mar 37.9 °C 23 % 35 km/h 0.0 mm High 33
26 Mar 38.2 °C 21 % 32 km/h 0.0 mm High 33
27 Mar 38.3 °C 21 % 40 km/h 0.0 mm High 36
28 Mar 38.2 °C 25 % 37 km/h 0.0 mm High 36
29 Mar 37.7 °C 26 % 44 km/h 0.1 mm Very high 40
30 Mar 37.9 °C 25 % 35 km/h 0.0 mm High 37
31 Mar 38.0 °C 28 % 30 km/h 0.0 mm High 35
1 Apr 38.0 °C 31 % 23 km/h 0.0 mm High 32
2 Apr 38.5 °C 29 % 32 km/h 0.0 mm High 36
3 Apr 38.6 °C 29 % 27 km/h 0.0 mm High 34
4 Apr 37.4 °C 33 % 25 km/h 0.0 mm High 33
5 Apr 38.1 °C 34 % 30 km/h 0.0 mm High 34
6 Apr 38.1 °C 33 % 27 km/h 0.0 mm High 32
7 Apr 37.9 °C 36 % 29 km/h 0.0 mm High 33
8 Apr 38.6 °C 24 % 33 km/h 0.0 mm High 38
9 Apr 38.6 °C 22 % 33 km/h 0.0 mm Very high 38
10 Apr 39.1 °C 22 % 38 km/h 0.0 mm Very high 42
11 Apr 38.4 °C 26 % 38 km/h 0.0 mm Very high 42
12 Apr 38.8 °C 21 % 23 km/h 0.0 mm High 36
13 Apr 39.1 °C 28 % 26 km/h 0.0 mm High 38
14 Apr 39.6 °C 25 % 27 km/h 0.0 mm Very high 38
15 Apr 40.0 °C 20 % 39 km/h 0.0 mm Very high 46
16 Apr 39.6 °C 19 % 32 km/h 0.0 mm Very high 42
17 Apr 38.4 °C 30 % 22 km/h 0.0 mm High 36
18 Apr 38.0 °C 35 % 27 km/h 0.0 mm High 36
19 Apr 38.7 °C 25 % 36 km/h 0.0 mm Very high 40
20 Apr 36.9 °C 37 % 37 km/h 0.1 mm High 36
21 Apr 38.5 °C 31 % 34 km/h 0.1 mm High 35
22 Apr after 38.9 °C 36 % 35 km/h 0.0 mm High 35
23 Apr after 36.5 °C 39 % 34 km/h 0.7 mm High 27
24 Apr after 35.6 °C 50 % 32 km/h 12.4 mm Low 6

Before and after, from space

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

Before · 26 Mar 2026
After · 28 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 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 guideline25 days
PM10282 µg/m³
Optical depth2.38
31123456789101112131415161718192021222324
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 · 411Every 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 Pong fire last?
GWIS (Copernicus) dates it between 2 April 2026 and 21 April 2026: 20 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 15,350 hectares (153.5 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 3 municipalities: Pong (14,818 ha, 8.7 %); Chiang Muan (490 ha, 0.7 %); Mueang Nan (115 ha, 0.1 %).
What was the weather like?
During the fire the temperature reached 40.0 °C, humidity dropped to 19 % and gusts hit 44 km/h. The fire danger index (FWI) reached 46, 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.