Burned area
satellite only9,096ha
Union of 2 GWIS (Copernicus) perimeters: overlapping areas count once.
- Source
- GWIS (Copernicus)
- Date
- 21 Mar 2020 – 7 Apr 2020
+− cross-check
No official record is matched to this page to compare it with.
TH · Thailand · –
Samoeng fire, 21 March 2020 สะเมิง · Samoeng
Out · last detection 7 Apr 2020, 19:06 UTC
The fire started on 21 March 2020 in Samoeng, Thailand, and satellites saw it burning for 18 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 9,096 hectares from heat detections, spread across a single municipality.
It is the 2th largest in Chiang Mai Province since 2016 (of 319 with a page). Number 11 in Thailand in 2020, of 457.
Use this data
Compare with…
Use this data
Fire page data · version 2026-10-26matches the official recordwith caveatssatellite onlymodel
When copying, the sentence is
Tick the figures you want: they make up the lede and the CSV.
Duration by satellite
satellite only18days
21 Mar 2020 to 7 Apr 2020: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 7 Apr 2020, 19:06 UTC
+− cross-check
Satellites pass a few times a day and cloud or smoke can hide the fire: a lack of detections is not an official extinction. Each country’s emergency service declares a fire contained or out.
Start
satellite only21 Mar 2020
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 21 Mar 2020
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only470
VIIRS detections at 375 m. Most intense hotspot: 35 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 21 Mar 2020 – 7 Apr 2020
+− cross-check
There is no official record to compare with. Each hotspot is a pixel detected in one satellite pass, not a separate fire.
The worst day
satellite only436MW
Total radiative power on 27 March 2020; hotspots that day: 118.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 27 Mar 2020
+− cross-check
Fire radiative power (FRP) measures the energy the fire gives off when the satellite passes. Added up by day, it compares intensity, not area.
Danger at the start
model36.4FWI · high
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 60.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 21 Mar 2020, local noon
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings
Weather during the fire
model39.0°C · 16% RH
High of 39.0 °C and minimum humidity of 16% on 3 April 2020; gusts of 36 km/h on 21 March 2020.
- Source
- weather model at the fire’s grid cell
- Date
- 21 Mar 2020 – 7 Apr 2020
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
Living inside
model≈ 650people
Estimated residents inside the perimeter and 6.1 ha of built-up area (100 m grid, epoch 2020).
- Source
- GHSL R2023A · JRC
- Date
- calculated on 24 October 2026
+− cross-check
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.
This page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
logLast day with fire: 4 April 2020 → 7 April 2020.
-
logStart date: 22 March 2020 → 21 March 2020.
-
· reconstructed GHSLPopulation and built-up area computed
What was saved on 26 October 2026
Every night a snapshot of what the page shows is saved. If anything changes, it appears in the list as a log entry.
- Area
- 9,276 ha
- Dates
- 21 Mar 2020 – 7 Apr 2020
- Name
- Samoeng
- Official record
- —
Versioned permanent link
https://worldfires.org/en/fire/samoeng-2020-03-5?v=2026-10-26A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire samoeng-2020-03-5.csv · daily, no individual hotspots
| fecha | focos_viirs | frp_mw | tmax_c | tmin_c | hr_min_pct | viento_max_kmh | racha_max_kmh | precip_mm | fwi | clase_fwi | dentro_del_incendio |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020-03-21 | 7 | 20 | 35.4 | 17.7 | 25 | 12.1 | 36 | 0 | 36.4 | alto | 1 |
| 2020-03-22 | 13 | 135 | 35.6 | 18.2 | 25 | 8.4 | 32 | 0.3 | 33.6 | alto | 1 |
| 2020-03-23 | 9 | 25 | 35.2 | 17.3 | 24 | 7.2 | 29.2 | 0 | 33 | alto | 1 |
| 2020-03-24 | 13 | 37 | 35.3 | 16.8 | 24 | 10.8 | 34.6 | 0 | 36.2 | alto | 1 |
| 2020-03-25 | 21 | 73 | 36.1 | 16.9 | 21 | 11.9 | 34.6 | 0 | 39.7 | muy_alto | 1 |
| 2020-03-26 | 18 | 64 | 36.7 | 17.4 | 22 | 11.1 | 33.5 | 0 | 39.2 | muy_alto | 1 |
| 2020-03-27 | 118 | 436 | 37 | 18.4 | 24 | 8.4 | 28.1 | 0 | 37 | alto | 1 |
| 2020-03-28 | 88 | 241 | 36.6 | 18.2 | 25 | 11.5 | 34.2 | 0 | 40.1 | muy_alto | 1 |
| 2020-03-29 | 41 | 131 | 38 | 19 | 19 | 9.9 | 30.6 | 0 | 40.8 | muy_alto | 1 |
| 2020-03-30 | 19 | 47 | 37.8 | 19.4 | 28 | 8.7 | 29.5 | 0 | 39.1 | muy_alto | 1 |
| 2020-03-31 | 29 | 79 | 38 | 20.7 | 25 | 9.7 | 32.4 | 0 | 40.3 | muy_alto | 1 |
| 2020-04-01 | 57 | 315 | 38.8 | 19.6 | 19 | 10.5 | 33.5 | 0 | 42.3 | muy_alto | 1 |
| 2020-04-02 | 21 | 131 | 38.7 | 19.6 | 20 | 11.8 | 34.2 | 0 | 43.8 | muy_alto | 1 |
| 2020-04-03 | 0 | 0 | 39 | 19 | 16 | 9.4 | 31.3 | 0 | 43.7 | muy_alto | 1 |
| 2020-04-04 | 3 | 8 | 38.5 | 19 | 19 | 10.3 | 31.7 | 0 | 44.9 | muy_alto | 1 |
| 2020-04-05 | 4 | 17 | 38 | 19.3 | 22 | 8.8 | 30.6 | 0 | 43.6 | muy_alto | 1 |
| 2020-04-06 | 1 | 5 | 36.9 | 21.1 | 32 | 9.7 | 31.7 | 0 | 38 | muy_alto | 1 |
| 2020-04-07 | 8 | 29 | 38.4 | 21.5 | 20 | 9.9 | 30.2 | 0 | 40.8 | muy_alto | 1 |
| 2020-04-08 | 0 | 0 | 36.5 | 20.6 | 26 | 9.4 | 29.5 | 0 | 40.6 | muy_alto | 0 |
| 2020-04-09 | 0 | 0 | 37 | 21.1 | 20 | 9.8 | 32 | 0 | 41.2 | muy_alto | 0 |
| 2020-04-10 | 0 | 0 | 37.9 | 19 | 20 | 10.4 | 34.6 | 0 | 42 | muy_alto | 0 |
| 2020-04-11 | 0 | 0 | 36.5 | 19.6 | 29 | 7.5 | 28.1 | 0.2 | 37.3 | alto | 0 |
| 2020-04-12 | 0 | 0 | 37 | 21.3 | 27 | 9 | 28.4 | 0 | 38.9 | muy_alto | 0 |
| 2020-04-13 | 0 | 0 | 37.5 | 20.4 | 24 | 10.6 | 40.7 | 0.1 | 40.6 | muy_alto | 0 |
| 2020-04-14 | 0 | 0 | 31.7 | 20.2 | 51 | 6.9 | 25.9 | 4.8 | 5 | muy_bajo | 0 |
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: GWIS (Copernicus), NASA FIRMS (VIIRS), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0), GHSL (JRC). Open-Meteo.com · How we build fire pages: methodology
- Burnt area
- 9,096ha
- GWIS perimeter (Copernicus)
- Duration
- 18days
- 21 Mar 2020 – 7 Apr 2020
- Municipalities hit
- 1
- districts
- Started on
- 21 Mar
- 2020
- Heat detections
- 470
- in a single hotspot: 35 MW
- Danger at start
- 36
- High · FWI index
- Average daily power
- 105MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
21 Mar7 Apr
7 Apr 2020
How it evolved, day by day
21 Mar
27 Mar
2 Apr
7 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
39°high
36km/h · peak gust
16%lowest humidity
It had gone more than two months without rain (1 mm or more) when it started. Rain came after the fire: 4.8 mm on 14 Apr.
This area had burned before
84% of the perimeter overlaps earlier fires recorded since 2016: 6,178 ha in 2016, 5,432 ha in 2019. Part of it burned more than once, so the yearly figures add up to more than the 7,670 ha that had burned before.
- 4,897 ha Hang Dong fire, March 2016 12,864 ha in total; the hectares shown are those it shares with this fire
- 1,210 ha Samoeng fire, March 2019 1,301 ha in total; the hectares shown are those it shares with this fire
- 1,005 ha Samoeng fire, March 2019 3,077 ha in total; the hectares shown are those it shares with this fire
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Bangkok boundary: geoBoundaries · OpenStreetMap, Wambacher · © OpenStreetMap contributors (ODbL 1.0).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
9,325 ha reached on 21 Mar9.2 %
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 2020Built-up area6.1 ha
Residents≈ 650
Inside the perimeter there were about 6.1 hectares of built-up land and about 650 residents (GHSL 2020, 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.
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)
Started with 60 days without rain: 14 % of the area in Thailand
| Day | High | Min. humidity | Peak gust | Rain | Danger (FWI) |
|---|---|---|---|---|---|
| 21 Mar | 35.4 °C | 25 % | 36 km/h | 0.0 mm | High 36 |
| 22 Mar | 35.6 °C | 25 % | 32 km/h | 0.3 mm | High 34 |
| 23 Mar | 35.2 °C | 24 % | 29 km/h | 0.0 mm | High 33 |
| 24 Mar | 35.3 °C | 24 % | 35 km/h | 0.0 mm | High 36 |
| 25 Mar | 36.1 °C | 21 % | 35 km/h | 0.0 mm | Very high 40 |
| 26 Mar | 36.7 °C | 22 % | 34 km/h | 0.0 mm | Very high 39 |
| 27 Mar | 37.0 °C | 24 % | 28 km/h | 0.0 mm | High 37 |
| 28 Mar | 36.6 °C | 25 % | 34 km/h | 0.0 mm | Very high 40 |
| 29 Mar | 38.0 °C | 19 % | 31 km/h | 0.0 mm | Very high 41 |
| 30 Mar | 37.8 °C | 28 % | 30 km/h | 0.0 mm | Very high 39 |
| 31 Mar | 38.0 °C | 25 % | 32 km/h | 0.0 mm | Very high 40 |
| 1 Apr | 38.8 °C | 19 % | 34 km/h | 0.0 mm | Very high 42 |
| 2 Apr | 38.7 °C | 20 % | 34 km/h | 0.0 mm | Very high 44 |
| 3 Apr | 39.0 °C | 16 % | 31 km/h | 0.0 mm | Very high 44 |
| 4 Apr | 38.5 °C | 19 % | 32 km/h | 0.0 mm | Very high 45 |
| 5 Apr | 38.0 °C | 22 % | 31 km/h | 0.0 mm | Very high 44 |
| 6 Apr | 36.9 °C | 32 % | 32 km/h | 0.0 mm | Very high 38 |
| 7 Apr | 38.4 °C | 20 % | 30 km/h | 0.0 mm | Very high 41 |
| 8 Apr after | 36.5 °C | 26 % | 30 km/h | 0.0 mm | Very high 41 |
| 9 Apr after | 37.0 °C | 20 % | 32 km/h | 0.0 mm | Very high 41 |
| 10 Apr after | 37.9 °C | 20 % | 35 km/h | 0.0 mm | Very high 42 |
| 11 Apr after | 36.5 °C | 29 % | 28 km/h | 0.2 mm | High 37 |
| 12 Apr after | 37.0 °C | 27 % | 28 km/h | 0.0 mm | Very high 39 |
| 13 Apr after | 37.5 °C | 24 % | 41 km/h | 0.1 mm | Very high 41 |
| 14 Apr after | 31.7 °C | 51 % | 26 km/h | 4.8 mm | Very low 5 |
Its twins: fires that started in the same weather
It started with an FWI of 36.4, a minimum humidity of 25% and more than two months without rain. Fires in the area that started in weather like this since 2016: 37.
FWI at the start
36.4
Minimum humidity
25 %
Days without rain
60+
this fire
chosen twins
rest of the area
Almost identicalSimilar
Outlines of the closest twins
This fire · Samoeng fire, 21 March 2020
9,096 ha
18 days
FWI 36.4
Min. humidity 25 %
Mae La Noi fire, March 2019
1,341 ha
14 days
FWI 36.3
Min. humidity 25 %
91 km away, in 2019
First rain (1 mm or more) after it ended: none in the following ten days.
Mae Taeng fire, March 2017
2,012 ha
12 days
FWI 35.8
Min. humidity 25 %
47 km away, in 2017
First rain (1 mm or more) after it ended: 2.5 mm on 27 Mar.
Khun Yuam fire, March 2019
3,087 ha
7 days
FWI 37.0
Min. humidity 25 %
86 km away, in 2019
First rain (1 mm or more) after it ended: none in the following ten days.
Bawlake fire, March 2017
2,129 ha
7 days
FWI 36.4
Min. humidity 25 %
118 km away, in 2017
First rain (1 mm or more) after it ended: none in the following ten days.
Pang Mapha fire, March 2017
1,648 ha
16 days
FWI 36.3
Min. humidity 25 %
115 km away, in 2017
First rain (1 mm or more) after it ended: 3.3 mm on 13 Apr.
What happened to them
- 8 days
- median duration
- 1,752 ha
- median area
- 100 %
- went past 1,000 ha
- 1.9 mm
- rain at the end (median; 13 of 37 had it)
It was 5.2 times larger than the median of its twins and lasted 18 days, against 8 days.
Only 1 of its 37 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 24 of 37, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 1.9 mm.
This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it
How it ended
4.8 mmfirst rain
14 Apr7 days after it ended
36km/h · max. gust
It was considered over on 7 Apr, and on 14 Apr 4.8 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 13 of 37, with a median of 1.9 mm.
Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)
How a twin is chosen
- Same area: fires that have already ended, less than 250 km from this one, since 2016.
- Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
- Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
- Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
- They are sorted by similarity, and the outlines of the first five are drawn.
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 14 Mar 2020
After · 14 Apr 2020
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.
Detections table · 470Every 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
Frequently asked questions
- How long did the Samoeng fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 21 March 2020 to 7 April 2020 (18 days). The perimeter dates it from 22 March 2020 to 4 April 2020.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 9,096 hectares (91.0 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Samoeng (9,325 ha, 9.2 %).
- What was the weather like?
- During the fire the temperature reached 39.0 °C, humidity dropped to 16 % and gusts hit 36 km/h. The fire danger index (FWI) reached 45, 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.
- How did the fires that started in similar weather in this area end?
- Fires less than 250 km away that started since 2016 with a similar FWI, humidity and dry spell: 37. Their median duration was 8 days and their median area 1,752 ha; 100 % went past 1,000 ha. Only 1 of its 37 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 24 of 37, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 1.9 mm.
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.
- Last day with fire: 4 April 2020 → 7 April 2020.
- Start date: 22 March 2020 → 21 March 2020.
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
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 2 polygons grouped in this page.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 22 March 2020 to 4 April 2020. 470 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 2020, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.
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.