Skip to content
worldfires
TH · Thailand · –

Pang Mapha fire, 23 March 2026 ปางมะผ้า · Pang Mapha, Mueang Mae Hong Son

Out · last detection 22 Apr 2026, 19:52 UTC

The fire started on 23 March 2026 in Pang Mapha, Thailand, and satellites saw it burning for 31 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 29,105 hectares from heat detections, spread across 2 municipalities.

Number 16 in Thailand in 2026, of 688.

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.

Burnt area
29,105ha
GWIS perimeter (Copernicus)
Duration
31days
23 Mar 2026 – 22 Apr 2026
Municipalities hit
2
districts
Started on
23 Mar
2026
Heat detections
912
in a single hotspot: 35 MW
Danger at start
21
High · FWI index
Average daily power
107MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 23 Mar22 Apr
22 Apr 2026

How it evolved, day by day

23 Mar 2026 · 1 MW · 2 24 Mar 2026 · 7 MW · 6 25 Mar 2026 · 40 MW · 13 26 Mar 2026 · 39 MW · 6 27 Mar 2026 · 49 MW · 13 28 Mar 2026 · 109 MW · 35 29 Mar 2026 · 159 MW · 60 30 Mar 2026 · 58 MW · 22 31 Mar 2026 · 35 MW · 8 1 Apr 2026 · 64 MW · 20 2 Apr 2026 · 238 MW · 83 3 Apr 2026 · 171 MW · 73 4 Apr 2026 · 47 MW · 19 5 Apr 2026 · 8 MW · 5 6 Apr 2026 · 29 MW · 13 7 Apr 2026 · 155 MW · 44 8 Apr 2026 · 335 MW · 114 9 Apr 2026 · 130 MW · 49 10 Apr 2026 · 16 MW · 14 11 Apr 2026 · 58 MW · 20 12 Apr 2026 · 95 MW · 26 13 Apr 2026 · 155 MW · 41 14 Apr 2026 · 131 MW · 42 15 Apr 2026 · 5 MW · 2 16 Apr 2026 · 43 MW · 11 17 Apr 2026 · 14 MW · 2 18 Apr 2026 · 147 MW · 31 19 Apr 2026 · 133 MW · 31 20 Apr 2026 · 31 MW · 10 21 Apr 2026 · 143 MW · 18 22 Apr 2026 · 674 MW · 79
23 Mar 30 Mar 6 Apr 13 Apr 22 Apr

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

Fire front film How it spread from one satellite pass to the next (64 passes) and with what wind. Watch the film

The weather it burned in

37°high
48km/h · peak gust
25%lowest humidity

It had gone 6 days without rain (1 mm or more) when it started. Rain came after the fire: 1.2 mm on 23 Apr.

This area had burned before

96% of the perimeter overlaps earlier fires recorded since 2016: 13,041 ha in 2016, 11,622 ha in 2017, 4,269 ha in 2018, 15,877 ha in 2019, 16,220 ha in 2020, 12,760 ha in 2021, 3,345 ha in 2022, 6,702 ha in 2023, 11,617 ha in 2024, 2,341 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 27,964 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 18% of the area of London (291 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. Pang Mapha ปางมะผ้า where it started
    29,183 ha reached on 23 Mar
    26 %
  2. Mueang Mae Hong Son เมืองแม่ฮ่องสอน
    1,378 ha reached on 28 Mar
    0.6 %

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 area12 ha
Residents≈ 1,700

Inside the perimeter there were about 12 hectares of built-up land and about 1,700 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 33.6 °C 37 % 36 km/h 0.2 mm High 21
22 Mar 32.6 °C 35 % 45 km/h 0.8 mm Moderate 19
23 Mar 32.8 °C 30 % 39 km/h 0.0 mm Moderate 21
24 Mar 33.5 °C 26 % 36 km/h 0.0 mm High 24
25 Mar 33.7 °C 27 % 35 km/h 0.0 mm High 24
26 Mar 34.4 °C 28 % 32 km/h 0.0 mm High 24
27 Mar 34.6 °C 29 % 39 km/h 0.0 mm High 26
28 Mar 35.2 °C 25 % 48 km/h 0.0 mm High 30
29 Mar 34.8 °C 26 % 45 km/h 0.0 mm High 30
30 Mar 35.1 °C 30 % 40 km/h 0.0 mm High 29
31 Mar 35.8 °C 31 % 37 km/h 0.0 mm High 29
1 Apr 35.7 °C 31 % 36 km/h 0.0 mm High 30
2 Apr 35.8 °C 29 % 37 km/h 0.0 mm High 30
3 Apr 36.8 °C 27 % 32 km/h 0.0 mm High 30
4 Apr 35.5 °C 34 % 34 km/h 0.0 mm High 30
5 Apr 35.3 °C 39 % 35 km/h 0.1 mm High 28
6 Apr 34.8 °C 38 % 33 km/h 0.1 mm High 28
7 Apr 34.1 °C 38 % 40 km/h 0.4 mm High 30
8 Apr 35.5 °C 30 % 42 km/h 0.5 mm High 32
9 Apr 33.9 °C 35 % 40 km/h 0.0 mm High 31
10 Apr 33.9 °C 33 % 44 km/h 0.0 mm High 32
11 Apr 35.1 °C 30 % 41 km/h 0.0 mm High 32
12 Apr 35.7 °C 26 % 36 km/h 0.0 mm High 32
13 Apr 36.4 °C 29 % 35 km/h 0.0 mm High 33
14 Apr 36.3 °C 29 % 32 km/h 0.0 mm High 32
15 Apr 36.0 °C 34 % 36 km/h 0.2 mm High 35
16 Apr 34.6 °C 32 % 32 km/h 0.1 mm High 33
17 Apr 36.3 °C 31 % 28 km/h 0.2 mm High 34
18 Apr 35.6 °C 37 % 34 km/h 0.1 mm High 34
19 Apr 35.4 °C 35 % 42 km/h 0.5 mm High 35
20 Apr 34.0 °C 40 % 38 km/h 0.1 mm High 32
21 Apr 36.1 °C 36 % 34 km/h 0.0 mm High 31
22 Apr 36.6 °C 34 % 36 km/h 0.2 mm High 31
23 Apr after 35.5 °C 39 % 36 km/h 1.2 mm High 25

Before and after, from space

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

Before · 16 Mar 2026
After · 29 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 3 April 2026 the air beside the fire reached 117 µg/m³ of PM2.5. That day averaged 71: 4.8 times the WHO daily guideline (15).

PM2.5 peak117 µg/m³
Days over the guideline35 days
PM10138 µg/m³
Optical depth1.54
21 Mar29 Mar6 Apr14 Apr22 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 · 912Every 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 Pang Mapha fire last?
GWIS (Copernicus) dates it between 23 March 2026 and 22 April 2026: 31 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 29,105 hectares (291.0 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Pang Mapha (29,183 ha, 26 %); Mueang Mae Hong Son (1,378 ha, 0.6 %).
What was the weather like?
During the fire the temperature reached 36.8 °C, humidity dropped to 25 % and gusts hit 48 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 · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Area: 30,393 → 29,105 ha.

RSS Changes to this page With cross-checks and a citable version

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; 9 polygons grouped in this page.
  • Dates from the perimeter: the VIIRS detections inside it did not change them. 912 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.