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Biriwa fire, 20 January 2019 Biriwa

Out · last detection 29 Jan 2019, 13:58 UTC

The fire started on 20 January 2019 in Biriwa, Sierra Leone, and satellites saw it burning for 10 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 2,503 hectares from heat detections, spread across a single municipality.

It is the 143th largest in Northern since 2016 (of 1112 with a page). Number 29 in Sierra Leone in 2019, of 180.

The power measured by the satellite is low (22.9 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…
Burnt area
2,503ha
GWIS perimeter (Copernicus)
Duration
10days
20 Jan 2019 – 29 Jan 2019
Municipalities hit
1
chiefdoms
Started on
20 Jan
2019
Heat detections
92
in a single hotspot: 23 MW
Danger at start
38
High · FWI index
Average daily power
70MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 20 Jan29 Jan
29 Jan 2019

How it evolved, day by day

20 Jan 2019 · 38 MW · 6 21 Jan 2019 · 35 MW · 8 22 Jan 2019 · 81 MW · 15 23 Jan 2019 · 30 MW · 9 26 Jan 2019 · 157 MW · 14 27 Jan 2019 · 104 MW · 19 28 Jan 2019 · 84 MW · 9 29 Jan 2019 · 33 MW · 7
20 Jan 22 Jan 26 Jan 28 Jan

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
29km/h · peak gust
13%lowest humidity

It had gone 37 days without rain (1 mm or more) when it started.

This area had burned before

59% of the perimeter overlaps earlier fires recorded since 2016: 1,488 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. Biriwa where it started
    2,519 ha reached on 19 Jan
    2.8 %

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 area1.1 ha
Residents≈ 450

Inside the perimeter there were about 1.1 hectares of built-up land and about 450 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)
20 Jan 35.6 °C 18 % 26 km/h 0.0 mm High 38
21 Jan 35.1 °C 28 % 29 km/h 0.0 mm Very high 38
22 Jan 36.4 °C 16 % 23 km/h 0.0 mm Very high 38
23 Jan 35.6 °C 19 % 24 km/h 0.0 mm Very high 40
24 Jan 35.1 °C 31 % 26 km/h 0.0 mm High 37
25 Jan 36.3 °C 20 % 22 km/h 0.0 mm High 36
26 Jan 36.3 °C 19 % 20 km/h 0.0 mm High 35
27 Jan 36.4 °C 13 % 26 km/h 0.0 mm Very high 41
28 Jan 35.1 °C 18 % 20 km/h 0.0 mm Very high 41
29 Jan 34.7 °C 30 % 25 km/h 0.0 mm High 38
30 Jan after 33.9 °C 32 % 33 km/h 0.0 mm High 38
31 Jan after 35.6 °C 24 % 24 km/h 0.0 mm High 37
1 Feb after 37.1 °C 23 % 30 km/h 0.0 mm Very high 40
2 Feb after 34.7 °C 35 % 30 km/h 0.0 mm High 36
3 Feb after 35.2 °C 30 % 35 km/h 0.0 mm Very high 38
4 Feb after 36.1 °C 26 % 31 km/h 0.0 mm High 38
5 Feb after 36.5 °C 28 % 27 km/h 0.0 mm High 36
6 Feb after 35.9 °C 33 % 27 km/h 0.0 mm High 37
7 Feb after 36.4 °C 28 % 27 km/h 0.0 mm High 36
8 Feb after 35.9 °C 26 % 31 km/h 0.0 mm Very high 39

Before and after, from space

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

Before · 13 Jan 2019
After · 5 Feb 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 · 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 Biriwa fire last?
GWIS (Copernicus) dates it between 20 January 2019 and 29 January 2019: 10 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 2,503 hectares (25.0 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Biriwa (2,519 ha, 2.8 %).
What was the weather like?
During the fire the temperature reached 36.4 °C, humidity dropped to 13 % and gusts hit 29 km/h. The fire danger index (FWI) reached 41, class Very 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; 2 polygons grouped in this page.
  • Dates from the perimeter: the VIIRS detections inside it did not change them. 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 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.