Mae Chaem fire, April 2023 Mae Chaem
The fire started on 9 April 2023 in Mae Chaem, Thailand, and satellites saw it burning for 4 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,187 hectares from heat detections, spread across a single municipality.
It is the 339th largest in Chiang Mai Province since 2016 (of 463 with a page). Number 386 in Thailand in 2023, of 500.
The power measured by the satellite is low (10.2 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
- 1,187ha
- GWIS perimeter (Copernicus)
- Duration
- 4days
- 9 Apr 2023 – 12 Apr 2023
- Municipalities hit
- 1
- districts
- Started on
- 9 Apr
- 2023
- Heat detections
- 42
- in a single hotspot: 10 MW
- Danger at start
- 26
- High · FWI index
- Energy released
- 159MW
- sum of detected power
Where it burned
How it evolved, day by day
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
It had gone 11 days without rain (1 mm or more) when it started.
This area had burned before
81% of the perimeter overlaps earlier fires recorded since 2016: 180 ha in 2016, 9 ha in 2018, 271 ha in 2019, 975 ha in 2020, 11 ha in 2021. Part of it burned more than once, so the yearly figures add up to more than the 958 ha that had burned before.
- 472 ha Mae Chaem fire, March 2020 1,042 ha in total; the hectares shown are those it shares with this fire
- 252 ha Mae Chaem fire, January 2020 1,052 ha in total; the hectares shown are those it shares with this fire
- 9 ha Mae Chaem fire, April 2018 1,167 ha in total; the hectares shown are those it shares with this fire
- 1 ha Mae Chaem fire, April 2016 1,147 ha in total; the hectares shown are those it shares with this fire
What happened to each town
-
Mae Chaem where it started1,192 ha reached on 5 Apr0.4 %
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) |
|---|---|---|---|---|---|
| 30 Mar | 33.1 °C | 39 % | 40 km/h | 0.2 mm | High 26 |
| 31 Mar | 32.7 °C | 41 % | 36 km/h | 0.2 mm | High 24 |
| 1 Apr | 33.7 °C | 39 % | 37 km/h | 0.4 mm | High 24 |
| 2 Apr | 33.3 °C | 36 % | 50 km/h | 0.0 mm | High 28 |
| 3 Apr | 31.8 °C | 41 % | 48 km/h | 0.3 mm | High 27 |
| 4 Apr | 33.0 °C | 36 % | 44 km/h | 0.0 mm | High 27 |
| 5 Apr | 34.3 °C | 33 % | 32 km/h | 0.0 mm | High 25 |
| 6 Apr | 35.1 °C | 36 % | 27 km/h | 0.0 mm | High 23 |
| 7 Apr | 35.0 °C | 39 % | 30 km/h | 0.4 mm | High 27 |
| 8 Apr | 35.4 °C | 38 % | 26 km/h | 0.1 mm | High 26 |
| 9 Apr | 36.0 °C | 33 % | 35 km/h | 0.0 mm | High 30 |
| 10 Apr | 35.7 °C | 36 % | 35 km/h | 0.0 mm | High 28 |
| 11 Apr | 35.7 °C | 37 % | 35 km/h | 0.1 mm | High 30 |
| 12 Apr | 35.6 °C | 37 % | 38 km/h | 0.0 mm | High 31 |
| 13 Apr after | 35.9 °C | 38 % | 38 km/h | 0.0 mm | High 32 |
| 14 Apr after | 36.9 °C | 33 % | 36 km/h | 0.0 mm | High 31 |
| 15 Apr after | 37.1 °C | 35 % | 30 km/h | 0.2 mm | High 29 |
| 16 Apr after | 36.6 °C | 34 % | 35 km/h | 0.0 mm | High 32 |
| 17 Apr after | 34.9 °C | 39 % | 39 km/h | 0.0 mm | High 32 |
| 18 Apr after | 36.9 °C | 36 % | 39 km/h | 0.0 mm | High 33 |
| 19 Apr after | 35.4 °C | 41 % | 38 km/h | 0.3 mm | High 32 |
| 20 Apr after | 34.1 °C | 48 % | 38 km/h | 0.4 mm | High 28 |
| 21 Apr after | 34.8 °C | 42 % | 37 km/h | 0.0 mm | High 28 |
| 22 Apr after | 35.8 °C | 37 % | 31 km/h | 0.9 mm | High 23 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
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 · CopernicusOn 12 April 2023 the air beside the fire reached 50 µg/m³ of PM2.5. That day averaged 38: 2.6 times the WHO daily guideline (15).
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 · 42Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
Frequently asked questions
- How long did the Mae Chaem fire last?
- GWIS (Copernicus) dates it between 9 April 2023 and 12 April 2023: 4 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 1,187 hectares (11.9 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Mae Chaem (1,192 ha, 0.4 %).
- What was the weather like?
- During the fire the temperature reached 36.0 °C, humidity dropped to 33 % and gusts hit 50 km/h. The fire danger index (FWI) reached 31, 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
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
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.