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Koya fire, 15 April 2026 Koya

Out · last detection 3 May 2026, 14:19 UTC

The fire started on 15 April 2026 in Koya, Sierra Leone, and satellites saw it burning for 18 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,150 hectares from heat detections, spread across a single municipality.

It is the 37th largest in Southern since 2016 (of 393 with a page). Number 49 in Sierra Leone in 2026, of 305.

Compare with…
Burnt area
3,150ha
GWIS perimeter (Copernicus)
Duration
18days
15 Apr 2026 – 2 May 2026
Municipalities hit
1
chiefdoms
Started on
15 Apr
2026
Heat detections
92
in a single hotspot: 104 MW
Danger at start
14
Moderate · FWI index
Average daily power
135MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 15 Apr2 May
3 May 2026

How it evolved, day by day

15 Apr 2026 · 20 MW · 3 16 Apr 2026 · 6 MW · 1 17 Apr 2026 · 125 MW · 4 18 Apr 2026 · 160 MW · 10 19 Apr 2026 · 91 MW · 7 21 Apr 2026 · 363 MW · 13 22 Apr 2026 · 28 MW · 4 23 Apr 2026 · 20 MW · 2 25 Apr 2026 · 716 MW · 21 26 Apr 2026 · 6 MW · 2 28 Apr 2026 · 111 MW · 5 29 Apr 2026 · 5 MW · 1 1 May 2026 · 112 MW · 5 2 May 2026 · 240 MW · 12 3 May 2026 · 26 MW · 2
15 Apr 18 Apr 22 Apr 25 Apr 26 Apr 1 May

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

The weather it burned in

36°high
36km/h · peak gust
34%lowest humidity

It had gone 0 days without rain (1 mm or more) when it started. Rain came after the fire: 5.8 mm on 3 May.

This area had burned before

76% of the perimeter overlaps earlier fires recorded since 2016: 505 ha in 2016, 732 ha in 2017, 994 ha in 2020, 536 ha in 2022, 456 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 2,381 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 2% of the area of London (32 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. Koya where it started
    3,173 ha reached on 15 Apr
    2.1 %

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 area5.5 ha
Residents≈ 1,600

Inside the perimeter there were about 5.5 hectares of built-up land and about 1,600 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)
15 Apr 35.6 °C 51 % 27 km/h 0.5 mm Moderate 14
16 Apr 32.1 °C 60 % 28 km/h 1.4 mm Low 8
17 Apr 33.8 °C 45 % 31 km/h 0.0 mm Moderate 17
18 Apr 34.2 °C 44 % 33 km/h 0.0 mm Moderate 21
19 Apr 34.1 °C 44 % 31 km/h 0.0 mm Moderate 21
20 Apr 33.6 °C 52 % 29 km/h 1.7 mm Low 10
21 Apr 33.7 °C 44 % 35 km/h 0.0 mm Moderate 20
22 Apr 34.3 °C 46 % 34 km/h 0.1 mm Moderate 20
23 Apr 33.1 °C 39 % 36 km/h 0.0 mm High 25
24 Apr 31.8 °C 40 % 35 km/h 0.0 mm High 26
25 Apr 34.1 °C 43 % 35 km/h 0.0 mm High 26
26 Apr 32.7 °C 46 % 33 km/h 0.0 mm High 25
27 Apr 33.9 °C 46 % 32 km/h 0.0 mm High 25
28 Apr 34.1 °C 39 % 36 km/h 0.0 mm High 27
29 Apr 33.9 °C 34 % 32 km/h 0.0 mm High 28
30 Apr 34.7 °C 46 % 22 km/h 0.0 mm High 26
1 May 35.1 °C 41 % 33 km/h 0.1 mm High 29
2 May 34.4 °C 48 % 34 km/h 0.1 mm High 28
3 May after 32.9 °C 62 % 29 km/h 5.8 mm Very low 4

Before and after, from space

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

Before · 8 Apr 2026
After · 9 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 19 April 2026 the air beside the fire reached 54 µg/m³ of PM2.5. That day averaged 44: 3.0 times the WHO daily guideline (15).

PM2.5 peak54 µg/m³
Days over the guideline19 days
PM10127 µg/m³
Optical depth0.96
13141516171819202122232425262728293012345
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 · 92Every 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 Sierra Leone ›

Frequently asked questions

How long did the Koya fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 15 April 2026 to 2 May 2026 (18 days). The perimeter dates it from 15 April 2026 to 25 April 2026.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,150 hectares (31.5 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Koya (3,173 ha, 2.1 %).
What was the weather like?
During the fire the temperature reached 35.6 °C, humidity dropped to 34 % and gusts hit 36 km/h. The fire danger index (FWI) reached 29, class High.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Sierra Leone (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.

RSS Changes to this page

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.

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How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 15 April 2026 to 25 April 2026. 92 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 ADM3 (Creative Commons Attribution 4.0 (CC BY 4.0)). 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.