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Nieni fire, 18 February 2019 Nieni

Out · last detection 8 Mar 2019, 13:45 UTC

The fire started on 18 February 2019 in Nieni, Sierra Leone, and satellites saw it burning for 18 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 2,520 hectares from heat detections, spread across a single municipality.

It is the 140th largest in Northern since 2016 (of 1112 with a page). Number 28 in Sierra Leone in 2019, of 182.

Compare with…
Burnt area
2,520ha
GWIS perimeter (Copernicus)
Duration
18days
18 Feb 2019 – 7 Mar 2019
Municipalities hit
1
chiefdoms
Started on
18 Feb
2019
Heat detections
135
in a single hotspot: 114 MW
Danger at start
45
Very high · FWI index
Average daily power
130MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 18 Feb7 Mar
8 Mar 2019

How it evolved, day by day

18 Feb 2019 · 19 MW · 2 19 Feb 2019 · 66 MW · 4 21 Feb 2019 · 31 MW · 6 22 Feb 2019 · 1,048 MW · 31 23 Feb 2019 · 305 MW · 27 24 Feb 2019 · 80 MW · 21 25 Feb 2019 · 37 MW · 4 26 Feb 2019 · 19 MW · 4 27 Feb 2019 · 103 MW · 12 28 Feb 2019 · 1 MW · 1 2 Mar 2019 · 8 MW · 1 3 Mar 2019 · 137 MW · 4 4 Mar 2019 · 7 MW · 6 5 Mar 2019 · 1 MW · 1 6 Mar 2019 · 13 MW · 1 7 Mar 2019 · 58 MW · 4 8 Mar 2019 · 274 MW · 6
18 Feb 22 Feb 25 Feb 28 Feb 4 Mar 7 Mar

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

The weather it burned in

38°high
37km/h · peak gust
8%lowest humidity

It had gone more than two months without rain (1 mm or more) when it started.

This area had burned before

59% of the perimeter overlaps earlier fires recorded since 2016: 12 ha in 2016, 1,484 ha in 2017.

How big is it?

10 km
It burned the equivalent of 1.6% of the area of London (25 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. Nieni where it started
    2,537 ha reached on 18 Feb
    1.1 %

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 2020
Built-up area0.74 ha
Residents≈ 250

Inside the perimeter there were about 0.74 hectares of built-up land and about 250 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)

Day High Min. humidity Peak gust Rain Danger (FWI)
18 Feb 35.1 °C 25 % 37 km/h 0.0 mm Very high 45
19 Feb 35.4 °C 19 % 31 km/h 0.0 mm Very high 42
20 Feb 34.0 °C 23 % 27 km/h 0.0 mm Very high 42
21 Feb 35.1 °C 25 % 22 km/h 0.0 mm High 37
22 Feb 37.5 °C 10 % 29 km/h 0.0 mm Very high 48
23 Feb 37.3 °C 8 % 29 km/h 0.0 mm Extreme 51
24 Feb 35.3 °C 15 % 30 km/h 0.0 mm Extreme 51
25 Feb 35.7 °C 23 % 28 km/h 0.0 mm Very high 44
26 Feb 35.4 °C 16 % 24 km/h 0.0 mm Very high 42
27 Feb 35.0 °C 9 % 32 km/h 0.0 mm Very high 46
28 Feb 34.7 °C 11 % 34 km/h 0.1 mm Very high 49
1 Mar 34.9 °C 11 % 37 km/h 0.0 mm Extreme 51
2 Mar 34.5 °C 8 % 26 km/h 0.0 mm Very high 48
3 Mar 35.6 °C 9 % 25 km/h 0.0 mm Very high 47
4 Mar 36.3 °C 9 % 29 km/h 0.0 mm Very high 49
5 Mar 36.0 °C 17 % 24 km/h 0.0 mm Very high 49
6 Mar 37.5 °C 12 % 21 km/h 0.0 mm Very high 49
7 Mar 37.2 °C 18 % 39 km/h 0.0 mm Extreme 56
8 Mar after 36.6 °C 15 % 37 km/h 0.0 mm Extreme 55
9 Mar after 36.2 °C 14 % 30 km/h 0.0 mm Extreme 52
10 Mar after 35.2 °C 24 % 27 km/h 0.0 mm Very high 45

Before and after, from space

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

Before · 11 Feb 2019
After · 14 Mar 2019

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 · 135Every 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 Nieni fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 18 February 2019 to 7 March 2019 (18 days). The perimeter dates it from 18 February 2019 to 28 February 2019.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 2,520 hectares (25.2 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Nieni (2,537 ha, 1.1 %).
What was the weather like?
During the fire the temperature reached 37.5 °C, humidity dropped to 8 % and gusts hit 37 km/h. The fire danger index (FWI) reached 51, class Extreme.
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 · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 28 February 2019 → 7 March 2019.

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 18 February 2019 to 28 February 2019. 135 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.

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.