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NE · Niger · –

Tillia fire, 26 September 2021 Tillia

Out · last measured on 28 Sept 2021

The fire started on 26 September 2021 in Tillia, Niger, and satellites saw it burning for 3 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,011 hectares from heat detections, spread across a single municipality.

It is the 58th largest in Tahoua since 2016 (of 59 with a page). Number 48 in Niger in 2021, of 48.

We have the GWIS perimeter for this fire, but the VIIRS sensors did not capture it in enough detail: no day-by-day evolution, but the split by municipality is there.

Burnt area
1,011ha
GWIS perimeter (Copernicus)
Duration
3days
26 Sept 2021 – 28 Sept 2021
Municipalities hit
1
communes
Started on
26 Sept
2021
Danger at start
55
Extreme · FWI index

Where it burned

The weather it burned in

40°high
36km/h · peak gust
12%lowest humidity

It had gone 28 days without rain (1 mm or more) when it started.

This area had burned before

No earlier perimeters overlap this fire since 2016, when the satellite record begins.

How big is it?

10 km
It burned the equivalent of 0.6% of the area of London (10 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. Tillia where it started
    1,020 ha
    0.1 %

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 area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (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)

Started with Very dry air: 73 % of the area in Niger

Day High Min. humidity Peak gust Rain Danger (FWI)
26 Sept 39.9 °C 12 % 27 km/h 0.0 mm Extreme 55
27 Sept 39.1 °C 13 % 36 km/h 0.0 mm Extreme 62
28 Sept 38.3 °C 15 % 34 km/h 0.0 mm Extreme 57
29 Sept after 38.1 °C 22 % 44 km/h 0.0 mm Extreme 67
30 Sept after 36.5 °C 26 % 40 km/h 0.0 mm Very high 50
1 Oct after 39.9 °C 8 % 38 km/h 0.0 mm Extreme 66
2 Oct after 40.0 °C 8 % 39 km/h 0.0 mm Very extreme 71
3 Oct after 39.2 °C 12 % 32 km/h 0.0 mm Extreme 65
4 Oct after 38.0 °C 21 % 21 km/h 0.0 mm Very high 49
5 Oct after 40.4 °C 10 % 39 km/h 0.0 mm Extreme 66
6 Oct after 40.1 °C 12 % 37 km/h 0.0 mm Extreme 65
7 Oct after 39.2 °C 9 % 35 km/h 0.0 mm Extreme 63
8 Oct after 39.3 °C 8 % 38 km/h 0.0 mm Extreme 67

Its twins: fires that started in the same weather

It started with an FWI of 55.3, a minimum humidity of 12% and 28 days without rain. Fires in the area that started in weather like this since 2017: 28.

FWI at the start 55.3
Minimum humidity 12 %
Days without rain 28
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Tillia fire, October 2024
1,974 ha 1 day FWI 53.7 Min. humidity 11 % 39 km away, in 2024

First rain (1 mm or more) after it ended: none in the following ten days.

What happened to them

1 day
median duration
1,758 ha
median area
100 %
went past 1,000 ha
—
rain at the end (median; 0 of 28 had it)

It stayed below its twins: 1,011 ha against a median of 1,758 ha. It lasted 3 days, against 1 day.

In none of them did 1 mm fall in the ten days after the end: they all went out without rain.

This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it

How it ended

—first rain
—no rain in ten days
36km/h · max. gust

It was considered over on 28 Sept, and not even 1 mm fell in the following ten days: it went out without rain. None of its 28 twins had rain when they ended.

Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

How a twin is chosen

  • Same area: fires that have already ended, less than 250 km from this one, since 2017.
  • Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
  • Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
  • Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
  • They are sorted by similarity, and the outlines of the first five are drawn.

How we calculate it

Before and after, from space

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

Before · 19 Sept 2021
After · 5 Oct 2021

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

Other fires nearby

All fires in Niger

Frequently asked questions

How long did the Tillia fire last?
GWIS (Copernicus) dates it between 26 September 2021 and 28 September 2021: 3 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 1,011 hectares (10.1 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Tillia (1,020 ha, 0.1 %).
What was the weather like?
During the fire the temperature reached 39.9 °C, humidity dropped to 12 % and gusts hit 36 km/h. The fire danger index (FWI) reached 62, class Extreme.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Niger (OCHA COD-AB). It is not an official report.
How did the fires that started in similar weather in this area end?
Fires less than 250 km away that started since 2017 with a similar FWI, humidity and dry spell: 28. Their median duration was 1 day and their median area 1,758 ha; 100 % went past 1,000 ha. In none of them did 1 mm fall in the ten days after the end: they all went out without rain.

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.

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
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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. No 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 OCHA COD-AB (IGNN) (Creative Commons Attribution for Intergovernmental Organisations (CC BY-IGO)). 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.