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Thong Pha Phum fire, 21 March 2026 ทองผาภูมิ · Sangkhla Buri, Thong Pha Phum

Out · last detection 30 Apr 2026, 06:50 UTC

The fire started on 21 March 2026 in Thong Pha Phum, Thailand, and satellites saw it burning for 41 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 21,046 hectares from heat detections, spread across 2 municipalities.

Number 24 in Thailand in 2026, of 689.

GWIS near-real-time perimeter, from the layer that changed in October 2025: this fire is not compared with fires from earlier years, because since then the GWIS layer gives more and larger perimeters.

The power measured by the satellite is low (28.8 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
21,046ha
GWIS perimeter (Copernicus)
Duration
41days
21 Mar 2026 – 30 Apr 2026
Municipalities hit
2
districts
Started on
21 Mar
2026
Heat detections
646
in a single hotspot: 29 MW
Danger at start
8
Low · FWI index
Average daily power
83MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 21 Mar30 Apr
30 Apr 2026

How it evolved, day by day

22 Mar 2026 · 3 MW · 1 23 Mar 2026 · 174 MW · 59 24 Mar 2026 · 54 MW · 29 25 Mar 2026 · 24 MW · 8 27 Mar 2026 · 39 MW · 9 28 Mar 2026 · 38 MW · 10 29 Mar 2026 · 15 MW · 3 31 Mar 2026 · 3 MW · 3 1 Apr 2026 · 26 MW · 6 2 Apr 2026 · 98 MW · 33 3 Apr 2026 · 271 MW · 63 4 Apr 2026 · 30 MW · 15 5 Apr 2026 · 12 MW · 7 7 Apr 2026 · 216 MW · 48 8 Apr 2026 · 212 MW · 54 9 Apr 2026 · 77 MW · 28 10 Apr 2026 · 9 MW · 6 11 Apr 2026 · 27 MW · 10 12 Apr 2026 · 150 MW · 33 13 Apr 2026 · 115 MW · 32 14 Apr 2026 · 98 MW · 23 15 Apr 2026 · 64 MW · 18 16 Apr 2026 · 160 MW · 24 17 Apr 2026 · 204 MW · 24 18 Apr 2026 · 225 MW · 51 19 Apr 2026 · 67 MW · 24 20 Apr 2026 · 99 MW · 15 22 Apr 2026 · 29 MW · 3 23 Apr 2026 · 27 MW · 3 24 Apr 2026 · 1 MW · 1 30 Apr 2026 · 18 MW · 3
22 Mar 3 Apr 15 Apr 23 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

38°high
40km/h · peak gust
29%lowest humidity

It had gone 0 days without rain (1 mm or more) when it started. Rain came after the fire: 3.0 mm on 1 May.

This area had burned before

43% of the perimeter overlaps earlier fires recorded since 2016: 326 ha in 2016, 763 ha in 2018, 4,494 ha in 2020, 628 ha in 2021, 5,407 ha in 2023, 1,997 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 8,959 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 13% of the area of London (210 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

  1. Sangkhla Buri สังขละบุรี
    13,830 ha reached on 23 Mar
    4.3 %
  2. Thong Pha Phum ทองผาภูมิ where it started
    7,321 ha reached on 22 Mar
    1.9 %

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 area0.76 ha
Residents≈ 60

Inside the perimeter there were about 0.76 hectares of built-up land and about 60 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)
18 Mar 33.1 °C 49 % 22 km/h 0.4 mm Low 8
19 Mar 34.3 °C 42 % 24 km/h 0.1 mm Moderate 14
20 Mar 34.0 °C 41 % 33 km/h 0.2 mm Moderate 17
21 Mar 34.5 °C 43 % 23 km/h 0.0 mm Moderate 15
22 Mar 33.7 °C 48 % 26 km/h 0.2 mm Moderate 16
23 Mar 35.3 °C 42 % 31 km/h 0.3 mm Moderate 18
24 Mar 36.6 °C 34 % 32 km/h 0.0 mm Moderate 21
25 Mar 36.8 °C 36 % 29 km/h 0.0 mm High 21
26 Mar 37.7 °C 35 % 29 km/h 0.0 mm High 22
27 Mar 36.9 °C 37 % 31 km/h 0.0 mm High 23
28 Mar 37.1 °C 34 % 32 km/h 0.0 mm High 24
29 Mar 35.0 °C 39 % 21 km/h 0.0 mm High 22
30 Mar 36.3 °C 40 % 30 km/h 0.1 mm High 25
31 Mar 36.2 °C 40 % 34 km/h 0.0 mm High 25
1 Apr 35.9 °C 40 % 29 km/h 0.0 mm High 25
2 Apr 37.6 °C 32 % 36 km/h 0.7 mm High 28
3 Apr 36.4 °C 38 % 40 km/h 0.0 mm High 29
4 Apr 34.7 °C 46 % 35 km/h 0.4 mm High 26
5 Apr 34.8 °C 44 % 36 km/h 0.0 mm High 27
6 Apr 35.2 °C 46 % 31 km/h 0.4 mm High 26
7 Apr 35.5 °C 40 % 36 km/h 0.2 mm High 27
8 Apr 36.2 °C 38 % 33 km/h 0.0 mm High 26
9 Apr 35.6 °C 41 % 36 km/h 0.0 mm High 28
10 Apr 36.2 °C 37 % 33 km/h 0.0 mm High 28
11 Apr 34.4 °C 48 % 38 km/h 0.2 mm High 27
12 Apr 36.1 °C 42 % 34 km/h 0.0 mm High 27
13 Apr 34.5 °C 45 % 34 km/h 0.0 mm High 27
14 Apr 37.5 °C 29 % 37 km/h 0.0 mm High 34
15 Apr 36.3 °C 34 % 34 km/h 0.0 mm High 33
16 Apr 37.7 °C 33 % 35 km/h 0.0 mm High 34
17 Apr 37.8 °C 32 % 36 km/h 0.0 mm High 35
18 Apr 37.7 °C 33 % 30 km/h 0.0 mm High 34
19 Apr 35.6 °C 39 % 34 km/h 0.0 mm High 33
20 Apr 36.2 °C 37 % 36 km/h 0.0 mm High 33
21 Apr 35.5 °C 41 % 40 km/h 0.0 mm High 34
22 Apr 35.7 °C 44 % 36 km/h 0.0 mm High 31
23 Apr 35.3 °C 46 % 30 km/h 1.3 mm Moderate 19
24 Apr 37.2 °C 37 % 27 km/h 0.0 mm High 27
25 Apr 35.5 °C 48 % 24 km/h 3.8 mm Low 7
26 Apr 38.0 °C 32 % 27 km/h 0.1 mm High 27
27 Apr 36.1 °C 42 % 31 km/h 0.1 mm High 27
28 Apr 37.0 °C 34 % 38 km/h 0.1 mm High 32
29 Apr 36.9 °C 34 % 35 km/h 0.0 mm High 30
30 Apr 35.5 °C 43 % 27 km/h 2.0 mm Moderate 14
1 May after 35.1 °C 50 % 30 km/h 3.0 mm Low 7

Before and after, from space

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

Before · 14 Mar 2026
After · 7 May 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 16 April 2026 the air beside the fire reached 114 µg/m³ of PM2.5. That day averaged 54: 3.6 times the WHO daily guideline (15).

PM2.5 peak114 µg/m³
Days over the guideline43 days
PM10121 µg/m³
Optical depth1.19
19 Mar29 Mar8 Apr18 Apr28 Apr
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 · 646Every 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 Thong Pha Phum fire last?
GWIS (Copernicus) dates it between 21 March 2026 and 30 April 2026: 41 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 21,046 hectares (210.5 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Sangkhla Buri (13,830 ha, 4.3 %); Thong Pha Phum (7,321 ha, 1.9 %).
What was the weather like?
During the fire the temperature reached 38.0 °C, humidity dropped to 29 % and gusts hit 40 km/h. The fire danger index (FWI) reached 35, class 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.

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.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 2 polygons grouped in this page.
  • Dates from the perimeter: the VIIRS detections inside it did not change them. 646 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.