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Mae La Noi fire, 18 March 2026 แม่ลาน้อย · Mae Sariang, Mae La Noi, Sop Moei

Out · last detection 27 Apr 2026, 19:59 UTC

The fire started on 18 March 2026 in Mae La Noi, Thailand, and satellites saw it burning for 41 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 157,976 hectares from heat detections, spread across 3 municipalities.

This page is probably a fire complex, not a single fire. GWIS merges into one perimeter the fires that touch over weeks, which in large burning seasons can join dozens of separate fires. The total area is reliable; the origin and dates refer to the whole complex.

Other fire pages in the same area and on the same dates:

The largest 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.

Compare with…

Suggestions: Mae Sariang · 2019Mae Sariang · 2018Mae Sariang · 2017Mae Sariang · 2023

Burnt area
157,976ha
GWIS perimeter (Copernicus)
Duration
41days
18 Mar 2026 – 27 Apr 2026
Municipalities hit
3
districts
Started on
18 Mar
2026
Heat detections
5,423
in a single hotspot: 585 MW
Danger at start
20
Moderate · FWI index
Average daily power
1.0GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 18 Mar27 Apr
27 Apr 2026

How it evolved, day by day

18 Mar 2026 · 5 MW · 2 19 Mar 2026 · 4 MW · 4 21 Mar 2026 · 292 MW · 24 22 Mar 2026 · 97 MW · 34 23 Mar 2026 · 350 MW · 112 24 Mar 2026 · 382 MW · 80 25 Mar 2026 · 648 MW · 74 26 Mar 2026 · 342 MW · 67 27 Mar 2026 · 1,518 MW · 142 28 Mar 2026 · 1,319 MW · 283 29 Mar 2026 · 742 MW · 246 30 Mar 2026 · 236 MW · 79 31 Mar 2026 · 773 MW · 77 1 Apr 2026 · 3,325 MW · 220 2 Apr 2026 · 3,210 MW · 597 3 Apr 2026 · 4,934 MW · 533 4 Apr 2026 · 464 MW · 101 5 Apr 2026 · 675 MW · 48 6 Apr 2026 · 1,581 MW · 79 7 Apr 2026 · 3,858 MW · 271 8 Apr 2026 · 6,986 MW · 695 9 Apr 2026 · 1,754 MW · 352 10 Apr 2026 · 1,244 MW · 218 11 Apr 2026 · 1,778 MW · 255 12 Apr 2026 · 703 MW · 134 13 Apr 2026 · 798 MW · 240 14 Apr 2026 · 235 MW · 99 15 Apr 2026 · 132 MW · 53 16 Apr 2026 · 144 MW · 27 17 Apr 2026 · 163 MW · 33 18 Apr 2026 · 268 MW · 73 19 Apr 2026 · 142 MW · 56 20 Apr 2026 · 107 MW · 18 21 Apr 2026 · 14 MW · 8 22 Apr 2026 · 74 MW · 21 23 Apr 2026 · 176 MW · 35 24 Apr 2026 · 75 MW · 20 25 Apr 2026 · 11 MW · 3 27 Apr 2026 · 23 MW · 10
18 Mar 27 Mar 8 Apr 20 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 (85 passes) and with what wind. Watch the film

The weather it burned in

37°high
39km/h · peak gust
30%lowest humidity

It had gone 3 days without rain (1 mm or more) when it started. Rain came after the fire: 3.3 mm on 29 Apr.

This area had burned before

96% of the perimeter overlaps earlier fires recorded since 2016: 51,894 ha in 2016, 67,656 ha in 2017, 66,974 ha in 2018, 97,664 ha in 2019, 69,275 ha in 2020, 64,866 ha in 2021, 23,436 ha in 2022, 53,179 ha in 2023, 60,421 ha in 2024, 47,986 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 152,092 ha that had burned before.

How big is it?

20 km
It burned almost the same area as London (1,580 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. Mae Sariang แม่สะเรียง
    111,876 ha reached on 18 Mar
    42 %
  2. Mae La Noi แม่ลาน้อย where it started
    28,400 ha reached on 19 Mar
    20 %
  3. Sop Moei สบเมย
    14,980 ha reached on 21 Mar
    10 %

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 area45 ha
Residents≈ 5,100

Inside the perimeter there were about 45 hectares of built-up land and about 5,100 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 34.5 °C 39 % 20 km/h 0.0 mm Moderate 20
19 Mar 34.4 °C 39 % 24 km/h 0.0 mm Moderate 21
20 Mar 32.8 °C 48 % 29 km/h 0.1 mm High 22
21 Mar 34.9 °C 43 % 32 km/h 0.1 mm High 23
22 Mar 35.1 °C 38 % 35 km/h 0.0 mm High 25
23 Mar 34.7 °C 34 % 30 km/h 0.0 mm High 25
24 Mar 35.0 °C 33 % 30 km/h 0.0 mm High 26
25 Mar 35.2 °C 32 % 30 km/h 0.0 mm High 27
26 Mar 36.0 °C 32 % 26 km/h 0.0 mm High 27
27 Mar 36.1 °C 33 % 34 km/h 0.0 mm High 30
28 Mar 36.5 °C 34 % 37 km/h 0.0 mm High 30
29 Mar 36.9 °C 30 % 36 km/h 0.0 mm High 31
30 Mar 36.5 °C 36 % 29 km/h 0.0 mm High 30
31 Mar 36.4 °C 40 % 27 km/h 0.0 mm High 29
1 Apr 36.9 °C 38 % 25 km/h 0.0 mm High 29
2 Apr 37.2 °C 36 % 26 km/h 0.0 mm High 30
3 Apr 37.2 °C 36 % 27 km/h 0.0 mm High 30
4 Apr 35.7 °C 44 % 26 km/h 0.0 mm High 28
5 Apr 35.7 °C 46 % 31 km/h 0.0 mm High 28
6 Apr 35.5 °C 49 % 31 km/h 0.0 mm High 26
7 Apr 33.6 °C 57 % 38 km/h 0.6 mm Moderate 21
8 Apr 36.3 °C 35 % 37 km/h 0.0 mm High 30
9 Apr 35.1 °C 40 % 33 km/h 0.0 mm High 29
10 Apr 36.2 °C 36 % 31 km/h 0.0 mm High 29
11 Apr 36.5 °C 33 % 30 km/h 0.0 mm High 30
12 Apr 36.2 °C 40 % 27 km/h 0.0 mm High 30
13 Apr 36.5 °C 42 % 28 km/h 0.0 mm High 30
14 Apr 36.8 °C 39 % 25 km/h 0.0 mm High 30
15 Apr 36.5 °C 38 % 33 km/h 0.0 mm High 32
16 Apr 36.4 °C 42 % 26 km/h 0.0 mm High 30
17 Apr 37.2 °C 40 % 26 km/h 0.1 mm High 30
18 Apr 36.6 °C 47 % 30 km/h 1.6 mm Moderate 16
19 Apr 36.0 °C 43 % 36 km/h 0.0 mm High 25
20 Apr 35.8 °C 41 % 36 km/h 0.0 mm High 27
21 Apr 35.8 °C 49 % 31 km/h 0.6 mm High 22
22 Apr 37.2 °C 42 % 28 km/h 0.1 mm High 26
23 Apr 36.5 °C 47 % 30 km/h 0.8 mm High 22
24 Apr 37.1 °C 46 % 22 km/h 0.0 mm High 23
25 Apr 34.3 °C 52 % 29 km/h 1.0 mm Moderate 17
26 Apr 35.2 °C 45 % 36 km/h 0.2 mm High 25
27 Apr 35.7 °C 46 % 39 km/h 0.3 mm High 26
28 Apr after 34.9 °C 44 % 39 km/h 0.3 mm High 27
29 Apr after 34.5 °C 48 % 24 km/h 3.3 mm Low 7

Before and after, from space

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

Before · 11 Mar 2026
After · 4 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 3 April 2026 the air beside the fire reached 94 µg/m³ of PM2.5. That day averaged 60: 4.0 times the WHO daily guideline (15).

PM2.5 peak94 µg/m³
Days over the guideline36 days
PM10113 µg/m³
Optical depth1.74
17 Mar26 Mar4 Apr13 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 · 5,423Every 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 Mae La Noi fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 18 March 2026 to 27 April 2026 (41 days). The perimeter dates it from 19 March 2026 to 23 April 2026.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 157,976 hectares (1,579.8 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 3 municipalities: Mae Sariang (111,876 ha, 42 %); Mae La Noi (28,400 ha, 20 %); Sop Moei (14,980 ha, 10 %).
What was the weather like?
During the fire the temperature reached 37.2 °C, humidity dropped to 30 % and gusts hit 39 km/h. The fire danger index (FWI) reached 32, 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 · 2 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 23 April 2026 → 27 April 2026.
  2. Start date: 19 March 2026 → 18 March 2026.

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; 22 polygons grouped in this page.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 19 March 2026 to 23 April 2026. 5,423 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.