Lac Iro fire, 20 December 2017 Lac Iro
The fire started on 20 December 2017 in Lac Iro, Chad, and satellites saw it burning for 4 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 4,000 hectares from heat detections, spread across a single municipality.
It is the 34th largest in Moyen-Chari since 2016 (of 225 with a page). Number 36 in Chad in 2017, of 171.
Compare with…
- Burnt area
- 4,000ha
- GWIS perimeter (Copernicus)
- Duration
- 4days
- 20 Dec 2017 – 23 Dec 2017
- Municipalities hit
- 1
- departments
- Started on
- 20 Dec
- 2017
- Heat detections
- 83
- in a single hotspot: 93 MW
- Danger at start
- 47
- Very high · FWI index
- Average daily power
- 318MW
- detected power per day, on average
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 44 days without rain (1 mm or more) when it started.
This area had burned before
12% of the perimeter overlaps earlier fires recorded since 2016: 510 ha in 2016. Part of it burned more than once, so the yearly figures add up to more than the 469 ha that had burned before.
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
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).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
Lac Iro where it started4,022 ha reached on 20 Dec0.2 %
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 2015Inside the perimeter there were about 0.08 hectares of built-up land and about 30 residents (GHSL 2015, 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)
| Day | High | Min. humidity | Peak gust | Rain | Danger (FWI) |
|---|---|---|---|---|---|
| 20 Dec | 36.8 °C | 14 % | 34 km/h | 0.0 mm | Very high 47 |
| 21 Dec | 37.6 °C | 16 % | 30 km/h | 0.0 mm | Very high 48 |
| 22 Dec | 37.5 °C | 18 % | 26 km/h | 0.0 mm | Very high 46 |
| 23 Dec | 37.3 °C | 21 % | 18 km/h | 0.0 mm | Very high 45 |
| 24 Dec after | 36.8 °C | 13 % | 38 km/h | 0.0 mm | Extreme 52 |
| 25 Dec after | 34.9 °C | 17 % | 36 km/h | 0.0 mm | Extreme 53 |
| 26 Dec after | 34.1 °C | 18 % | 36 km/h | 0.0 mm | Extreme 53 |
| 27 Dec after | 33.8 °C | 16 % | 30 km/h | 0.0 mm | Very high 49 |
| 28 Dec after | 33.9 °C | 16 % | 27 km/h | 0.0 mm | Very high 49 |
| 29 Dec after | 33.3 °C | 18 % | 28 km/h | 0.0 mm | Very high 48 |
| 30 Dec after | 34.4 °C | 16 % | 30 km/h | 0.0 mm | Very high 49 |
| 31 Dec after | 34.4 °C | 18 % | 34 km/h | 0.0 mm | Extreme 51 |
| 1 Jan after | 32.9 °C | 15 % | 40 km/h | 0.0 mm | Extreme 56 |
| 2 Jan after | 32.0 °C | 11 % | 41 km/h | 0.0 mm | Extreme 58 |
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.
Detections table · 83Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 3,845 haLac Iro18 December 2018 · 8 days · 6 km away
- 8,437 haLac Iro31 December 2025 · 19 days · 9 km away
- 4,476 haLac Iro21 December 2017 · 4 days · 11 km away
- 3,298 haLac Iro16 January 2026 · 12 days · 13 km away
- 4,115 haLac Iro15 January 2026 · 5 days · 17 km away
- 4,384 haLac Iro25 December 2016 · 9 days · 18 km away
Frequently asked questions
- How long did the Lac Iro fire last?
- GWIS (Copernicus) dates it between 20 December 2017 and 23 December 2017: 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 4,000 hectares (40.0 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Lac Iro (4,022 ha, 0.2 %).
- What was the weather like?
- During the fire the temperature reached 37.6 °C, humidity dropped to 14 % and gusts hit 34 km/h. The fire danger index (FWI) reached 48, class Very high.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Chad (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.
Satellite cross-check
History of this page Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
No changes 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
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
- Dates from the perimeter: the VIIRS detections inside it did not change them. 83 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 2015, 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.