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AR · Argentina · –

Pelegrini fire, September 2025 Pelegrini

Out · last detection 14 Sept 2025, 17:39 UTC

The fire started on 7 September 2025 in Pelegrini, Argentina, and satellites saw it burning for 11 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,855 hectares from heat detections, spread across a single municipality.

It is the 168th largest in Santiago del Estero since 2016 (of 294 with a page). Number 90 in Argentina in 2025, of 133.

Burnt area
1,855ha
GWIS perimeter (Copernicus)
Duration
11days
7 Sept 2025 – 17 Sept 2025
Municipalities hit
1
departments
Started on
7 Sept
2025
Heat detections
101
in a single hotspot: 244 MW
Danger at start
28
High · FWI index
Average daily power
313MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 7 Sept17 Sept
14 Sept 2025

How it evolved, day by day

9 Sept 2025 · 42 MW · 14 10 Sept 2025 · 20 MW · 11 12 Sept 2025 · 257 MW · 5 13 Sept 2025 · 1,166 MW · 34 14 Sept 2025 · 82 MW · 37
9 Sept 10 Sept 12 Sept 13 Sept 14 Sept

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

The weather it burned in

35°high
52km/h · peak gust
18%lowest humidity

It had gone 7 days without rain (1 mm or more) when it started. Rain came after the fire: 3.1 mm on 18 Sept.

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 1.2% of the area of London (19 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. Pelegrini where it started
    1,860 ha reached on 9 Sept
    0.3 %

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 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)
7 Sept 23.5 °C 24 % 36 km/h 0.0 mm High 28
8 Sept 29.2 °C 18 % 29 km/h 0.0 mm Moderate 18
9 Sept 30.7 °C 19 % 40 km/h 0.0 mm High 29
10 Sept 35.1 °C 19 % 51 km/h 0.0 mm Very high 48
11 Sept 28.6 °C 20 % 45 km/h 0.0 mm High 38
12 Sept 31.4 °C 25 % 35 km/h 0.0 mm High 34
13 Sept 35.2 °C 29 % 49 km/h 0.0 mm Very high 47
14 Sept 32.5 °C 39 % 47 km/h 0.4 mm Very high 42
15 Sept 30.1 °C 40 % 52 km/h 0.0 mm Very high 39
16 Sept 29.9 °C 44 % 25 km/h 0.0 mm Moderate 21
17 Sept 34.4 °C 36 % 45 km/h 10.7 mm High 34
18 Sept after 34.2 °C 43 % 39 km/h 3.1 mm Low 7

Its twins: fires that started in the same weather

It started with an FWI of 28.5, a minimum humidity of 24% and 7 days without rain. Fires in the area that started in weather like this since 2016: 34.

FWI at the start 28.5
Minimum humidity 24 %
Days without rain 7
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Metán fire, November 2019
1,709 ha 3 days FWI 28.3 Min. humidity 25 % 84 km away, in 2019

First rain (1 mm or more) after it ended: 3.0 mm on 22 Nov.

What happened to them

4 days
median duration
1,968 ha
median area
100 %
went past 1,000 ha
6.2 mm
rain at the end (median; 20 of 34 had it)

It burned an area similar to its twins (1,855 ha against a median of 1,968 ha) and lasted 11 days, against 4 days.

In 14 of 34, 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 6.2 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

3.1 mmfirst rain
18 Septthe day after it ended
52km/h · max. gust

It was considered over on 17 Sept, and on 18 Sept 3.1 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 20 of 34, with a median of 6.2 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.

How we calculate it

Before and after, from space

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

Before · 31 Aug 2025
After · 24 Sept 2025

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 18 September 2025 the air beside the fire reached 44 µg/m³ of PM2.5. That day averaged 24: 1.6 times the WHO daily guideline (15).

PM2.5 peak44 µg/m³
Days over the guideline3 days
PM1044 µg/m³
Optical depth0.71
5 Sept9 Sept13 Sept17 Sept
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 · 101Every 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 Argentina

Frequently asked questions

How long did the Pelegrini fire last?
GWIS (Copernicus) dates it between 7 September 2025 and 17 September 2025: 11 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 1,855 hectares (18.6 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Pelegrini (1,860 ha, 0.3 %).
What was the weather like?
During the fire the temperature reached 35.2 °C, humidity dropped to 18 % and gusts hit 52 km/h. The fire danger index (FWI) reached 48, class Very high.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Argentina (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: 34. Their median duration was 4 days and their median area 1,968 ha; 100 % went past 1,000 ha. In 14 of 34, 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 6.2 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: 911 · 100 · 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 911 · 100.

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. 101 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 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.