Burned area
satellite only16,139ha
Perimeter published by GWIS (Copernicus).
- Source
- GWIS (Copernicus)
- Date
- 21 Dec 2023 – 9 Jan 2024
+− cross-check
No official record is matched to this page to compare it with.
SS · South Sudan · –
Wulu fire, 21 December 2023 Wulu
Out · last detection 10 Jan 2024, 10:53 UTC
The fire started on 21 December 2023 in Wulu, South Sudan, and satellites saw it burning for 20 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 16,139 hectares from heat detections, spread across a single municipality.
It is the 11th largest in Lakes since 2016 (of 119 with a page). Number 12 in South Sudan in 2023, of 106.
Use this data
Compare with…
Suggestions: Wulu · 2020Ibba · 2016Wulu · 2016Wulu · 2020
Use this data
Fire page data · version 2026-10-26matches the official recordwith caveatssatellite onlymodel
When copying, the sentence is
Tick the figures you want: they make up the lede and the CSV.
Duration by satellite
satellite only20days
21 Dec 2023 to 9 Jan 2024: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 10 Jan 2024, 10:53 UTC
+− cross-check
Satellites pass a few times a day and cloud or smoke can hide the fire: a lack of detections is not an official extinction. Each country’s emergency service declares a fire contained or out.
Start
satellite only21 Dec 2023
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 21 Dec 2023
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only642
VIIRS detections at 375 m. Most intense hotspot: 190 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 21 Dec 2023 – 9 Jan 2024
+− cross-check
There is no official record to compare with. Each hotspot is a pixel detected in one satellite pass, not a separate fire.
The worst day
satellite only1,815MW
Total radiative power on 9 January 2024; hotspots that day: 58.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 9 Jan 2024
+− cross-check
Fire radiative power (FRP) measures the energy the fire gives off when the satellite passes. Added up by day, it compares intensity, not area.
Danger at the start
model38.5FWI · very high
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 17.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 21 Dec 2023, local noon
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings
Weather during the fire
model38.3°C · 20% RH
High of 38.3 °C and minimum humidity of 20% on 22 December 2023; gusts of 35 km/h on 24 December 2023.
- Source
- weather model at the fire’s grid cell
- Date
- 21 Dec 2023 – 9 Jan 2024
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
This page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
logLast day with fire: 6 January 2024 → 9 January 2024.
-
logStart date: 26 December 2023 → 21 December 2023.
-
· reconstructed GHSLPopulation and built-up area computed
What was saved on 26 October 2026
Every night a snapshot of what the page shows is saved. If anything changes, it appears in the list as a log entry.
- Area
- 16,139 ha
- Dates
- 21 Dec 2023 – 9 Jan 2024
- Name
- Wulu
- Official record
- —
Versioned permanent link
https://worldfires.org/en/fire/wulu-2023-12-4?v=2026-10-26A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire wulu-2023-12-4.csv · daily, no individual hotspots
| fecha | focos_viirs | frp_mw | tmax_c | tmin_c | hr_min_pct | viento_max_kmh | racha_max_kmh | precip_mm | fwi | clase_fwi | dentro_del_incendio |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2023-12-21 | 1 | 6 | 37 | 25 | 22 | 7.9 | 20.5 | 0 | 38.5 | muy_alto | 1 |
| 2023-12-22 | 10 | 40 | 38.3 | 22.9 | 20 | 9.5 | 29.2 | 0 | 47.8 | muy_alto | 1 |
| 2023-12-23 | 11 | 40 | 37.5 | 25.1 | 19 | 12.2 | 29.5 | 0 | 53.4 | extremo | 1 |
| 2023-12-24 | 39 | 137 | 36.4 | 24 | 18 | 14.6 | 35.3 | 0 | 54.8 | extremo | 1 |
| 2023-12-25 | 28 | 127 | 36.5 | 24.1 | 14 | 14 | 33.1 | 0 | 58.2 | extremo | 1 |
| 2023-12-26 | 62 | 742 | 35.7 | 23 | 17 | 13 | 31.3 | 0 | 59.6 | extremo | 1 |
| 2023-12-27 | 39 | 388 | 35.7 | 23.7 | 19 | 13 | 32.4 | 0 | 60.1 | extremo | 1 |
| 2023-12-28 | 86 | 614 | 35.5 | 25.1 | 21 | 9.7 | 23.4 | 0 | 52.2 | extremo | 1 |
| 2023-12-29 | 94 | 596 | 35.7 | 24.2 | 17 | 11.9 | 31 | 0 | 55.5 | extremo | 1 |
| 2023-12-30 | 63 | 593 | 36.5 | 23.5 | 17 | 11.2 | 29.9 | 0 | 56.2 | extremo | 1 |
| 2023-12-31 | 34 | 202 | 36.4 | 24.4 | 16 | 13.9 | 34.2 | 0 | 60 | extremo | 1 |
| 2024-01-01 | 15 | 117 | 35.3 | 24 | 16 | 9 | 24.8 | 0 | 50.6 | extremo | 1 |
| 2024-01-02 | 39 | 433 | 36.9 | 25.5 | 19 | 13.8 | 29.9 | 0 | 59 | extremo | 1 |
| 2024-01-03 | 9 | 39 | 36.8 | 25.5 | 13 | 14.6 | 34.9 | 0 | 61.3 | extremo | 1 |
| 2024-01-04 | 27 | 204 | 36.7 | 22.9 | 11 | 13.3 | 32 | 0 | 62.7 | extremo | 1 |
| 2024-01-05 | 22 | 97 | 35.2 | 21.9 | 12 | 8.9 | 25.2 | 0 | 55.6 | extremo | 1 |
| 2024-01-06 | 3 | 27 | 35.8 | 22.6 | 13 | 12 | 31.3 | 0 | 63.5 | extremo | 1 |
| 2024-01-07 | 0 | 0 | 35.2 | 22.4 | 12 | 12.1 | 30.2 | 0 | 66.1 | extremo | 1 |
| 2024-01-08 | 0 | 0 | 36.7 | 22.6 | 13 | 11.2 | 28.8 | 0 | 61.3 | extremo | 1 |
| 2024-01-09 | 58 | 1,815 | 37 | 23 | 14 | 11.7 | 30.2 | 0 | 61.7 | extremo | 1 |
| 2024-01-10 | 2 | 14 | 37.1 | 24.4 | 15 | 11.4 | 28.4 | 0 | 63.3 | extremo | 0 |
| 2024-01-11 | 0 | 0 | 37.6 | 24.1 | 15 | 14.1 | 34.9 | 0 | 67 | extremo | 0 |
| 2024-01-12 | 0 | 0 | 36.5 | 24.4 | 15 | 14.3 | 36 | 0 | 68.8 | extremo | 0 |
| 2024-01-13 | 0 | 0 | 35.7 | 22.6 | 15 | 7.9 | 22.3 | 0 | 54.7 | extremo | 0 |
| 2024-01-14 | 0 | 0 | 37.7 | 22.6 | 13 | 13.3 | 32 | 0 | 63.7 | extremo | 0 |
| 2024-01-15 | 0 | 0 | 36.1 | 24.1 | 15 | 13.6 | 33.8 | 0 | 66.3 | extremo | 0 |
| 2024-01-16 | 0 | 0 | 35.3 | 22.9 | 11 | 13.5 | 32 | 0 | 67.4 | extremo | 0 |
| 2024-01-17 | 0 | 0 | 32.6 | 24.2 | 14 | 11.9 | 28.8 | 0 | 61.5 | extremo | 0 |
| 2024-01-18 | 0 | 0 | 34.5 | 22 | 14 | 11.7 | 30.2 | 0 | 64 | extremo | 0 |
| 2024-01-19 | 0 | 0 | 35.1 | 23.7 | 10 | 12.6 | 28.8 | 0 | 65.9 | extremo | 0 |
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: GWIS (Copernicus), NASA FIRMS (VIIRS), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0), GHSL (JRC). Open-Meteo.com · How we build fire pages: methodology
- Burnt area
- 16,139ha
- GWIS perimeter (Copernicus)
- Duration
- 20days
- 21 Dec 2023 – 9 Jan 2024
- Municipalities hit
- 1
- counties
- Started on
- 21 Dec
- 2023
- Heat detections
- 642
- in a single hotspot: 190 MW
- Danger at start
- 38
- Very high · FWI index
- Average daily power
- 328MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
21 Dec9 Jan
10 Jan 2024
How it evolved, day by day
21 Dec
25 Dec
29 Dec
2 Jan
9 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
38°high
35km/h · peak gust
11%lowest humidity
It had gone 17 days without rain (1 mm or more) when it started.
This area had burned before
85% of the perimeter overlaps earlier fires recorded since 2016: 9,072 ha in 2016, 7,488 ha in 2017, 5,042 ha in 2020, 1,216 ha in 2021, 2,605 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 13,746 ha that had burned before.
- 5,831 ha Wulu fire, December 2016 11,622 ha in total; the hectares shown are those it shares with this fire
- 364 ha Wulu fire, January 2020 5,553 ha in total; the hectares shown are those it shares with this fire
- 302 ha Wulu fire, January 2016 5,441 ha in total; the hectares shown are those it shares with this fire
- 222 ha Wulu fire, December 2016 61,053 ha in total; the hectares shown are those it shares with this fire
- 198 ha Wulu fire, November 2017 23,579 ha in total; the hectares shown are those it shares with this fire
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
Wulu where it started16,240 ha reached on 21 Dec1.4 %
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 2025Built-up area< 0.1 ha
Residents< 20
Inside the perimeter there was no noticeable built-up land and almost nobody lived there (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) |
|---|---|---|---|---|---|
| 21 Dec | 37.0 °C | 22 % | 20 km/h | 0.0 mm | Very high 38 |
| 22 Dec | 38.3 °C | 20 % | 29 km/h | 0.0 mm | Very high 48 |
| 23 Dec | 37.5 °C | 19 % | 30 km/h | 0.0 mm | Extreme 53 |
| 24 Dec | 36.4 °C | 18 % | 35 km/h | 0.0 mm | Extreme 55 |
| 25 Dec | 36.5 °C | 14 % | 33 km/h | 0.0 mm | Extreme 58 |
| 26 Dec | 35.7 °C | 17 % | 31 km/h | 0.0 mm | Extreme 60 |
| 27 Dec | 35.7 °C | 19 % | 32 km/h | 0.0 mm | Extreme 60 |
| 28 Dec | 35.5 °C | 21 % | 23 km/h | 0.0 mm | Extreme 52 |
| 29 Dec | 35.7 °C | 17 % | 31 km/h | 0.0 mm | Extreme 56 |
| 30 Dec | 36.5 °C | 17 % | 30 km/h | 0.0 mm | Extreme 56 |
| 31 Dec | 36.4 °C | 16 % | 34 km/h | 0.0 mm | Extreme 60 |
| 1 Jan | 35.3 °C | 16 % | 25 km/h | 0.0 mm | Extreme 51 |
| 2 Jan | 36.9 °C | 19 % | 30 km/h | 0.0 mm | Extreme 59 |
| 3 Jan | 36.8 °C | 13 % | 35 km/h | 0.0 mm | Extreme 61 |
| 4 Jan | 36.7 °C | 11 % | 32 km/h | 0.0 mm | Extreme 63 |
| 5 Jan | 35.2 °C | 12 % | 25 km/h | 0.0 mm | Extreme 56 |
| 6 Jan | 35.8 °C | 13 % | 31 km/h | 0.0 mm | Extreme 64 |
| 7 Jan | 35.2 °C | 12 % | 30 km/h | 0.0 mm | Extreme 66 |
| 8 Jan | 36.7 °C | 13 % | 29 km/h | 0.0 mm | Extreme 61 |
| 9 Jan | 37.0 °C | 14 % | 30 km/h | 0.0 mm | Extreme 62 |
| 10 Jan after | 37.1 °C | 15 % | 28 km/h | 0.0 mm | Extreme 63 |
| 11 Jan after | 37.6 °C | 15 % | 35 km/h | 0.0 mm | Extreme 67 |
| 12 Jan after | 36.5 °C | 15 % | 36 km/h | 0.0 mm | Extreme 69 |
| 13 Jan after | 35.7 °C | 15 % | 22 km/h | 0.0 mm | Extreme 55 |
| 14 Jan after | 37.7 °C | 13 % | 32 km/h | 0.0 mm | Extreme 64 |
| 15 Jan after | 36.1 °C | 15 % | 34 km/h | 0.0 mm | Extreme 66 |
| 16 Jan after | 35.3 °C | 11 % | 32 km/h | 0.0 mm | Extreme 67 |
| 17 Jan after | 32.6 °C | 14 % | 29 km/h | 0.0 mm | Extreme 62 |
| 18 Jan after | 34.5 °C | 14 % | 30 km/h | 0.0 mm | Extreme 64 |
| 19 Jan after | 35.1 °C | 10 % | 29 km/h | 0.0 mm | Extreme 66 |
Its twins: fires that started in the same weather
It started with an FWI of 38.5, a minimum humidity of 22% and 17 days without rain. Fires in the area that started in weather like this since 2016: 47.
FWI at the start
38.5
Minimum humidity
22 %
Days without rain
17
this fire
chosen twins
rest of the area
Almost identicalSimilar
Outlines of the closest twins
This fire · Wulu fire, 21 December 2023
16,139 ha
20 days
FWI 38.5
Min. humidity 22 %
Wulu fire, December 2020
6,657 ha
8 days
FWI 38.2
Min. humidity 21 %
18 km away, in 2020
First rain (1 mm or more) after it ended: none in the following ten days.
Ibba fire, December 2016
6,738 ha
12 days
FWI 38.7
Min. humidity 22 %
40 km away, in 2016
First rain (1 mm or more) after it ended: none in the following ten days.
Mundri West fire, December 2017
5,505 ha
13 days
FWI 38.5
Min. humidity 21 %
94 km away, in 2017
First rain (1 mm or more) after it ended: none in the following ten days.
Nzara fire, December 2016
11,886 ha
8 days
FWI 38.6
Min. humidity 23 %
127 km away, in 2016
First rain (1 mm or more) after it ended: none in the following ten days.
Nzara fire, December 2017
17,262 ha
13 days
FWI 39.5
Min. humidity 21 %
135 km away, in 2017
First rain (1 mm or more) after it ended: none in the following ten days.
What happened to them
- 13 days
- median duration
- 9,122 ha
- median area
- 47 %
- went past 10,000 ha
- 1.6 mm
- rain at the end (median; 8 of 47 had it)
It was 1.8 times larger than the median of its twins and lasted 20 days, against 13 days.
Only 9 of its 47 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 39 of 47, 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 1.6 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
35km/h · max. gust
It was considered over on 9 Jan, and not even 1 mm fell in the following ten days: it went out without rain. Twins with rain when they ended: 8 of 47, with a median of 1.6 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 2016.
- 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.
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 14 Dec 2023
After · 16 Jan 2024
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
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 · CopernicusOn 7 January 2024 the air beside the fire reached 120 µg/m³ of PM2.5. That day averaged 61: 4.1 times the WHO daily guideline (15).
PM2.5 peak120 µg/m³
Days over the guideline17 days
PM10173 µg/m³
Optical depth1.07
WHO 15
24 Dec28 Dec1 Jan5 Jan9 Jan
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 · 642Every 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
- 44,549 haWulu8 December 2025 · 23 days · 12 km away
- 23,579 haWulu30 November 2017 · 19 days · 19 km away
- 28,216 haWulu18 December 2024 · 33 days · 26 km away
- 23,328 haWulu4 December 2016 · 18 days · 29 km away
- 61,053 haWulu5 December 2016 · 27 days · 32 km away
- 22,366 haWulu21 December 2023 · 26 days · 38 km away
Frequently asked questions
- How long did the Wulu fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 21 December 2023 to 9 January 2024 (20 days). The perimeter dates it from 26 December 2023 to 6 January 2024.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 16,139 hectares (161.4 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Wulu (16,240 ha, 1.4 %).
- What was the weather like?
- During the fire the temperature reached 38.3 °C, humidity dropped to 11 % and gusts hit 35 km/h. The fire danger index (FWI) reached 66, class Extreme.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of South Sudan (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 2016 with a similar FWI, humidity and dry spell: 47. Their median duration was 13 days and their median area 9,122 ha; 47 % went past 10,000 ha. Only 9 of its 47 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 39 of 47, 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 1.6 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.
Satellite cross-check
History of this page · 2 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
- Last day with fire: 6 January 2024 → 9 January 2024.
- Start date: 26 December 2023 → 21 December 2023.
RSS Changes to this page With cross-checks and a citable version
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
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 26 December 2023 to 6 January 2024. 642 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.
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 (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.