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Masimera fire, 5 April 2026 Masimera, Marampa

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

The fire started on 5 April 2026 in Masimera, Sierra Leone, and satellites saw it burning for 29 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 5,307 hectares from heat detections, spread across 2 municipalities.

It is the 19th largest in Northern since 2016 (of 1112 with a page). Number 14 in Sierra Leone in 2026, of 305.

Compare with…
Burnt area
5,307ha
GWIS perimeter (Copernicus)
Duration
29days
5 Apr 2026 – 3 May 2026
Municipalities hit
2
chiefdoms
Started on
5 Apr
2026
Heat detections
151
in a single hotspot: 206 MW
Danger at start
24
High · FWI index
Average daily power
136MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 5 Apr3 May
3 May 2026

How it evolved, day by day

5 Apr 2026 · 227 MW · 5 6 Apr 2026 · 457 MW · 12 9 Apr 2026 · 12 MW · 1 10 Apr 2026 · 134 MW · 4 14 Apr 2026 · 126 MW · 9 16 Apr 2026 · 339 MW · 9 17 Apr 2026 · 146 MW · 8 18 Apr 2026 · 271 MW · 22 19 Apr 2026 · 136 MW · 10 20 Apr 2026 · 2 MW · 1 21 Apr 2026 · 110 MW · 12 22 Apr 2026 · 372 MW · 12 23 Apr 2026 · 86 MW · 5 25 Apr 2026 · 118 MW · 15 26 Apr 2026 · 55 MW · 9 28 Apr 2026 · 11 MW · 3 29 Apr 2026 · 56 MW · 4 1 May 2026 · 8 MW · 2 2 May 2026 · 21 MW · 3 3 May 2026 · 25 MW · 5
5 Apr 6 Apr 10 Apr 17 Apr 20 Apr 23 Apr 28 Apr 2 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
32%lowest humidity

It had gone 21 days without rain (1 mm or more) when it started. Rain came after the fire: 1.6 mm on 5 May.

This area had burned before

50% of the perimeter overlaps earlier fires recorded since 2016: 66 ha in 2017, 1,720 ha in 2018, 1,558 ha in 2020, 392 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 2,663 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 3.4% of the area of London (53 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. Masimera where it started
    4,724 ha reached on 5 Apr
    7.0 %
  2. 618 ha reached on 5 Apr
    1.5 %

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 area11 ha
Residents≈ 3,800

Inside the perimeter there were about 11 hectares of built-up land and about 3,800 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)
5 Apr 35.2 °C 36 % 31 km/h 0.1 mm High 24
6 Apr 35.6 °C 42 % 32 km/h 0.0 mm High 25
7 Apr 34.8 °C 43 % 31 km/h 0.1 mm High 25
8 Apr 35.9 °C 41 % 36 km/h 0.2 mm High 26
9 Apr 34.2 °C 50 % 31 km/h 0.6 mm Moderate 20
10 Apr 35.8 °C 44 % 31 km/h 0.3 mm Moderate 21
11 Apr 31.1 °C 58 % 25 km/h 5.2 mm Very low 4
12 Apr 36.1 °C 46 % 27 km/h 0.6 mm Moderate 13
13 Apr 35.5 °C 37 % 32 km/h 0.1 mm High 23
14 Apr 33.8 °C 55 % 28 km/h 1.5 mm Low 9
15 Apr 35.6 °C 46 % 22 km/h 0.4 mm Moderate 17
16 Apr 32.9 °C 56 % 32 km/h 1.4 mm Low 11
17 Apr 34.6 °C 45 % 28 km/h 0.0 mm Moderate 18
18 Apr 35.6 °C 39 % 32 km/h 0.0 mm High 25
19 Apr 35.0 °C 41 % 28 km/h 0.0 mm High 24
20 Apr 34.3 °C 49 % 31 km/h 3.7 mm Low 6
21 Apr 34.6 °C 42 % 31 km/h 0.0 mm Moderate 19
22 Apr 35.1 °C 44 % 30 km/h 1.2 mm Moderate 17
23 Apr 34.3 °C 35 % 35 km/h 0.0 mm High 26
24 Apr 33.8 °C 34 % 36 km/h 0.0 mm High 28
25 Apr 35.5 °C 37 % 33 km/h 0.0 mm High 28
26 Apr 33.7 °C 41 % 32 km/h 0.0 mm High 27
27 Apr 34.2 °C 44 % 29 km/h 0.0 mm High 27
28 Apr 35.2 °C 36 % 33 km/h 0.0 mm High 29
29 Apr 34.6 °C 32 % 28 km/h 0.0 mm High 30
30 Apr 35.4 °C 42 % 20 km/h 0.0 mm High 28
1 May 36.3 °C 37 % 32 km/h 0.1 mm High 30
2 May 35.3 °C 44 % 32 km/h 0.3 mm High 29
3 May 33.7 °C 57 % 28 km/h 5.2 mm Low 6
4 May after 34.8 °C 49 % 30 km/h 0.6 mm Moderate 15
5 May after 32.5 °C 57 % 32 km/h 1.6 mm Low 10

Before and after, from space

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

Before · 29 Mar 2026
After · 10 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 21 April 2026 the air beside the fire reached 69 µg/m³ of PM2.5. That day averaged 49: 3.3 times the WHO daily guideline (15).

PM2.5 peak69 µg/m³
Days over the guideline29 days
PM10126 µg/m³
Optical depth1.31
3456789101112131415161718192021222324252627282930123456
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 · 151Every 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 Masimera fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 5 April 2026 to 3 May 2026 (29 days). The perimeter dates it from 12 April 2026 to 26 April 2026.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 5,307 hectares (53.1 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Masimera (4,724 ha, 7.0 %); Marampa (618 ha, 1.5 %).
What was the weather like?
During the fire the temperature reached 36.3 °C, humidity dropped to 32 % and gusts hit 36 km/h. The fire danger index (FWI) reached 30, 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; 2 polygons grouped in this page.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 12 April 2026 to 26 April 2026. 151 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.