How long did the Usuk fire last?

GWIS (Copernicus) dates it between 7 December 2025 and 10 December 2025: 4 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 1,228 hectares (12.3 km²). It is an estimate: official national figures may differ.

Which municipalities burned?

The fire only entered Usuk (1,236 ha, 0.5 %).

Where does this data come from?

From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Uganda (geoBoundaries). It is not an official report.

UG · Uganda · 2025-12-07 → 2025-12-10

Usuk fire, December 2025 Usuk

Out · last detection 10 Dec 2025, 10:31 UTC

The fire started on 7 December 2025 in Usuk, Uganda, and satellites saw it burning for 4 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,228 hectares from heat detections, spread across a single municipality.

It is the 12th largest in Eastern Region since 2016 (of 27 with a page). Number 159 in Uganda in 2025, of 226.

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: Usuk · 2020 Usuk · 2025 Pian · 2025 Pian · 2025

Burnt area: 1,228ha; GWIS perimeter (Copernicus)
Duration: 4days; 7 Dec 2025 – 10 Dec 2025
Municipalities hit: 1; counties
Started on: 7 Dec; 2025
Heat detections: 19; in a single hotspot: 17 MW
Average daily power: 40MW; detected power per day, on average

HOTSPOTS BY DAY 7 Dec10 Dec

Play back 10 Dec 2025

How it evolved, day by day

7 Dec 8 Dec 10 Dec

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

This area had burned before

16% of the perimeter overlaps earlier fires recorded since 2016: 192 ha in 2020.

192 ha Usuk fire, January 2020 1,145 ha in total; the hectares shown are those it shares with this fire

How big is it?

It burned the equivalent of 0.8% of the area of London (12 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

Usuk where it started

1,236 ha reached on 7 Dec

0.5 %

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 area3.7 ha

Residents≈ 300

Inside the perimeter there were about 3.7 hectares of built-up land and about 300 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

Before and after, from space

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

↔

Before · 30 Nov 2025

After · 17 Dec 2025

Before After

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 11 December 2025 the air beside the fire reached 26 µg/m³ of PM2.5. That day averaged 18: 1.2 times the WHO daily guideline (15).

PM2.5 peak26 µg/m³

Days over the guideline1 day

PM1026 µg/m³

Optical depth0.41

WHO 15

5678910111213

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 · 19Every 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 time	Satellite	FRP (MW)	Lat	Lon

Other fires nearby

All fires in Uganda ›

Frequently asked questions

How long did the Usuk fire last?: GWIS (Copernicus) dates it between 7 December 2025 and 10 December 2025: 4 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 1,228 hectares (12.3 km²). It is an estimate: official national figures may differ.
Which municipalities burned?: The fire only entered Usuk (1,236 ha, 0.5 %).
Where does this data come from?: From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Uganda (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.

Emergency number: 999 · 112 · Emergency number and official warnings ›

Satellite cross-check

NASA FIRMS ↗
GWIS · Copernicus ↗

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.

Report an error

What do you think is wrong?

Dates or duration Place or towns Burned area Name It was not a wildfire Same fire as another page Something else

What really happened?

Your connection to the fire (optional) Email (optional)

We will only use your email to reply about this report. Privacy. This is not an emergency service: if there is a fire now, call 999 · 112.

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. 19 Suomi-NPP VIIRS detections on those dates.
We have not matched this page with any official record.
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 ADM2 (Public Domain). 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.

Where it burned