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ZA · South Africa ·

Joe Morolong fire, July 2021 Joe Morolong

Out · last detection 20 Jul 2021, 13:15 UTC

The fire started on 20 July 2021 in Joe Morolong, South Africa, and satellites saw it burning for 1 day. Copernicus’s global GWIS system rebuilt a burnt perimeter of 4,988 hectares from heat detections, spread across a single municipality.

It is the 19th largest in Nothern Cape since 2016 (of 101 with a page). Number 22 in South Africa in 2021, of 156.

Burnt area
4,988ha
GWIS perimeter (Copernicus)
Duration
1day
20 Jul 2021 – 20 Jul 2021
Municipalities hit
1
municipalities
Started on
20 Jul
2021
Heat detections
146
in a single hotspot: 106 MW
Danger at start
52
Extreme · FWI index
Average daily power
3.4GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 20 Jul20 Jul

How it evolved, day by day

20 Jul 2021 · 3,380 MW · 146

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

The weather it burned in

22°high
46km/h · peak gust
14%lowest humidity

It had gone 40 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 3.2% of the area of London (50 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. Joe Morolong where it started
    4,995 ha reached on 20 Jul
    0.2 %

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 area0.29 ha
Residents< 20

Inside the perimeter there were about 0.29 hectares of 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: 37 % of the area in South Africa

Day High Min. humidity Peak gust Rain Danger (FWI)
20 Jul 22.4 °C 14 % 46 km/h 0.0 mm Extreme 52
21 Jul after 14.7 °C 15 % 37 km/h 0.0 mm Extreme 51
22 Jul after 13.5 °C 27 % 30 km/h 0.0 mm High 36
23 Jul after 15.8 °C 14 % 33 km/h 0.0 mm Very high 40
24 Jul after 19.2 °C 22 % 44 km/h 0.0 mm Very high 46
25 Jul after 18.8 °C 21 % 47 km/h 0.0 mm Extreme 50
26 Jul after 19.4 °C 19 % 50 km/h 0.0 mm Extreme 52
27 Jul after 20.3 °C 23 % 49 km/h 0.0 mm Extreme 52
28 Jul after 23.0 °C 20 % 40 km/h 0.0 mm Very high 43
29 Jul after 23.3 °C 17 % 23 km/h 0.0 mm Very high 40
30 Jul after 25.2 °C 12 % 28 km/h 0.0 mm Very high 43

Its twins: fires that started in the same weather

It started with an FWI of 52.2, a minimum humidity of 14% and 40 days without rain. Fires in the area that started in weather like this since 2017: 35.

FWI at the start 52.2
Minimum humidity 14 %
Days without rain 40
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Ga-Segonyana fire, August 2023
4,783 ha 1 day FWI 51.4 Min. humidity 13 % 187 km away, in 2023

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

What happened to them

3 days
median duration
2,923 ha
median area
100 %
went past 1,000 ha
3.0 mm
rain at the end (median; 7 of 35 had it)

It was 1.7 times larger than the median of its twins and lasted 1 day, against 3 days.

Only 9 of its 35 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 28 of 35, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.0 mm.

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
46km/h · max. gust

It was considered over on 20 Jul, and not even 1 mm fell in the following ten days: it went out without rain. Twins with rain when they ended: 7 of 35, with a median of 3.0 mm.

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 · 13 Jul 2021
After · 27 Jul 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.

Detections table · 146Every 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 South Africa

Frequently asked questions

How long did the Joe Morolong fire last?
GWIS (Copernicus) dates it between 20 July 2021 and 20 July 2021: 1 day 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 4,988 hectares (49.9 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Joe Morolong (4,995 ha, 0.2 %).
What was the weather like?
During the fire the temperature reached 22.4 °C, humidity dropped to 14 % and gusts hit 46 km/h. The fire danger index (FWI) reached 52, class Extreme.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of South Africa (geoBoundaries). 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: 35. Their median duration was 3 days and their median area 2,923 ha; 100 % went past 1,000 ha. Only 9 of its 35 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 28 of 35, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.0 mm.

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: 10177 · 112 · Emergency number and official warnings

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
What do you think is wrong?

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 10177 · 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. 146 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 3.0 Intergovernmental Organisations (CC BY 3.0 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.