Derre fire, 6 September 2023 Derre
The fire started on 6 September 2023 in Derre, Mozambique, and satellites saw it burning for 9 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,087 hectares from heat detections, spread across a single municipality.
It is the 793th largest in Zambézia since 2016 (of 842 with a page). Number 122 in Mozambique in 2023, of 128.
The power measured by the satellite is low (17.2 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.
Compare with…
Suggestions: Derre · 2022Derre · 2016Derre · 2021Mocuba · 2018
- Burnt area
- 3,087ha
- GWIS perimeter (Copernicus)
- Duration
- 9days
- 6 Sept 2023 – 14 Sept 2023
- Municipalities hit
- 1
- districts
- Started on
- 6 Sept
- 2023
- Heat detections
- 118
- in a single hotspot: 17 MW
- Danger at start
- 34
- High · FWI index
- Average daily power
- 99MW
- 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 7 days without rain (1 mm or more) when it started.
This area had burned before
99% of the perimeter overlaps earlier fires recorded since 2016: 2,564 ha in 2016, 768 ha in 2017, 1,659 ha in 2018, 2,242 ha in 2019, 180 ha in 2020, 1,815 ha in 2021, 2,551 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 3,049 ha that had burned before.
- 2,549 ha Derre fire, October 2022 15,820 ha in total; the hectares shown are those it shares with this fire
- 2,002 ha Derre fire, September 2016 116,560 ha in total; the hectares shown are those it shares with this fire
- 1,235 ha Derre fire, September 2021 4,224 ha in total; the hectares shown are those it shares with this fire
- 1,211 ha Mocuba fire, September 2018 116,289 ha in total; the hectares shown are those it shares with this fire
- 581 ha Derre fire, September 2021 3,339 ha in total; the hectares shown are those it shares with this fire
- 365 ha Derre fire, September 2017 3,629 ha in total; the hectares shown are those it shares with this fire
- 355 ha Derre fire, September 2019 10,860 ha in total; the hectares shown are those it shares with this fire
- 150 ha Morrumbala fire, September 2020 33,528 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).
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
-
Derre where it started3,101 ha reached on 1 Sept0.6 %
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.
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) |
|---|---|---|---|---|---|
| 6 Sept | 34.1 °C | 25 % | 30 km/h | 0.0 mm | High 34 |
| 7 Sept | 31.8 °C | 30 % | 31 km/h | 0.0 mm | High 34 |
| 8 Sept | 30.1 °C | 38 % | 30 km/h | 0.0 mm | High 30 |
| 9 Sept | 30.2 °C | 35 % | 35 km/h | 0.0 mm | High 31 |
| 10 Sept | 33.5 °C | 30 % | 34 km/h | 0.0 mm | High 30 |
| 11 Sept | 34.4 °C | 28 % | 40 km/h | 0.0 mm | High 33 |
| 12 Sept | 36.7 °C | 22 % | 48 km/h | 0.2 mm | Very high 45 |
| 13 Sept | 28.8 °C | 53 % | 38 km/h | 3.9 mm | Low 6 |
| 14 Sept | 28.2 °C | 48 % | 29 km/h | 2.8 mm | Low 6 |
| 15 Sept after | 31.7 °C | 34 % | 24 km/h | 0.0 mm | Moderate 17 |
| 16 Sept after | 35.9 °C | 23 % | 40 km/h | 0.0 mm | High 33 |
| 17 Sept after | 37.7 °C | 19 % | 37 km/h | 0.0 mm | High 37 |
| 18 Sept after | 33.7 °C | 24 % | 42 km/h | 0.0 mm | Very high 43 |
| 19 Sept after | 31.8 °C | 33 % | 33 km/h | 0.0 mm | High 33 |
| 20 Sept after | 34.4 °C | 26 % | 27 km/h | 0.0 mm | High 32 |
| 21 Sept after | 35.2 °C | 26 % | 36 km/h | 0.0 mm | High 36 |
| 22 Sept after | 34.6 °C | 26 % | 35 km/h | 0.0 mm | High 37 |
| 23 Sept after | 35.5 °C | 21 % | 37 km/h | 0.0 mm | High 38 |
| 24 Sept after | 36.2 °C | 22 % | 29 km/h | 0.0 mm | High 38 |
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 13 September 2023 the air beside the fire reached 74 µg/m³ of PM2.5. That day averaged 31: 2.1 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 · 118Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 116,560 haDerre2 September 2016 · 31 days · 3 km away
- 72,800 haDerre8 September 2025 · 33 days · 10 km away
- 47,144 haDerreSeptember 2022 · 20 days · 17 km away
- 72,301 haDerre21 August 2026 · 28 days · 19 km away
- 86,463 haMocuba13 September 2020 · 22 days · 22 km away
- 41,830 haMilange15 September 2020 · 26 days · 35 km away
Frequently asked questions
- How long did the Derre fire last?
- GWIS (Copernicus) dates it between 6 September 2023 and 14 September 2023: 9 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 3,087 hectares (30.9 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Derre (3,101 ha, 0.6 %).
- What was the weather like?
- During the fire the temperature reached 36.7 °C, humidity dropped to 22 % and gusts hit 48 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 Mozambique (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. 118 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.
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.