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AR · Argentina · –

General Alvear fire, January 2023 General Alvear, San Martín

Out · last detection 18 Jan 2023, 17:24 UTC

The fire started on 7 January 2023 in General Alvear, Argentina, and satellites saw it burning for 12 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,532 hectares from heat detections, spread across 2 municipalities.

It is the 193th largest in Corrientes since 2016 (of 198 with a page). Number 172 in Argentina in 2023, of 179.

Burnt area
1,532ha
GWIS perimeter (Copernicus)
Duration
12days
7 Jan 2023 – 18 Jan 2023
Municipalities hit
2
departments
Started on
7 Jan
2023
Heat detections
51
in a single hotspot: 65 MW
Danger at start
32
High · FWI index
Average daily power
134MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 7 Jan18 Jan
18 Jan 2023

How it evolved, day by day

7 Jan 2023 · 7 MW · 1 9 Jan 2023 · 12 MW · 2 10 Jan 2023 · 31 MW · 3 11 Jan 2023 · 108 MW · 6 12 Jan 2023 · 140 MW · 15 15 Jan 2023 · 30 MW · 2 16 Jan 2023 · 730 MW · 21 18 Jan 2023 · 11 MW · 1
7 Jan 10 Jan 12 Jan 16 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

37°high
34km/h · peak gust
19%lowest humidity

It had gone 4 days without rain (1 mm or more) when it started. Rain came after the fire: 2.2 mm on 21 Jan.

This area had burned before

63% of the perimeter overlaps earlier fires recorded since 2016: 267 ha in 2018, 879 ha in 2020. Part of it burned more than once, so the yearly figures add up to more than the 967 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 1% of the area of London (15 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. General Alvear where it started
    1,437 ha reached on 7 Jan
    0.7 %
  2. 97 ha reached on 16 Jan
    0.0 %

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 Jan 35.9 °C 21 % 32 km/h 0.0 mm High 32
8 Jan 35.5 °C 21 % 27 km/h 0.0 mm High 28
9 Jan 36.8 °C 19 % 30 km/h 0.0 mm High 28
10 Jan 36.3 °C 28 % 28 km/h 1.6 mm High 34
11 Jan 36.6 °C 28 % 27 km/h 0.0 mm High 24
12 Jan 35.5 °C 33 % 34 km/h 7.2 mm High 26
13 Jan 24.4 °C 72 % 27 km/h 31.3 mm Very low 0
14 Jan 30.2 °C 35 % 32 km/h 0.0 mm Very low 2
15 Jan 33.4 °C 31 % 27 km/h 0.0 mm Moderate 12
16 Jan 35.2 °C 32 % 20 km/h 0.0 mm Moderate 13
17 Jan 37.0 °C 34 % 28 km/h 0.0 mm Moderate 18
18 Jan 36.0 °C 42 % 27 km/h 0.1 mm Moderate 17
19 Jan after 36.2 °C 40 % 31 km/h 0.5 mm Moderate 16
20 Jan after 36.9 °C 34 % 21 km/h 0.0 mm High 23
21 Jan after 34.4 °C 39 % 41 km/h 2.2 mm High 30

Its twins: fires that started in the same weather

It started with an FWI of 31.7, a minimum humidity of 21% and 4 days without rain. Fires in the area that started in weather like this since 2016: 24.

FWI at the start 31.7
Minimum humidity 21 %
Days without rain 4
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Santo Tomé fire, February 2022
2,631 ha 5 days FWI 30.2 Min. humidity 22 % 45 km away, in 2022

First rain (1 mm or more) after it ended: 2.8 mm on 24 Feb.

What happened to them

5 days
median duration
2,416 ha
median area
100 %
went past 1,000 ha
3.0 mm
rain at the end (median; 24 of 24 had it)

It stayed below its twins: 1,532 ha against a median of 2,416 ha. It lasted 12 days, against 5 days.

All of them had rain in the ten days after the end: 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

2.2 mmfirst rain
21 Jan3 days after it ended
34km/h · max. gust

It was considered over on 18 Jan, and on 21 Jan 2.2 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 24 of 24, 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 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 Dec 2022
After · 25 Jan 2023

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 12 January 2023 the air beside the fire reached 16 µg/m³ of PM2.5, but no daily average passed the WHO guideline (15).

PM2.5 peak16 µg/m³
Days over the guideline0 days
PM1023 µg/m³
Optical depth0.72
7 Jan10 Jan13 Jan16 Jan19 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 · 51Every 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 General Alvear fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 7 January 2023 to 18 January 2023 (12 days). The perimeter dates it from 9 January 2023 to 16 January 2023.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,532 hectares (15.3 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: General Alvear (1,437 ha, 0.7 %); San Martín (97 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 37.0 °C, humidity dropped to 19 % and gusts hit 34 km/h. The fire danger index (FWI) reached 34, class 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: 24. Their median duration was 5 days and their median area 2,416 ha; 100 % went past 1,000 ha. All of them had rain in the ten days after the end: 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: 911 · 100 · Emergency number and official warnings

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.
  1. Last day with fire: 16 January 2023 → 18 January 2023.
  2. Start date: 9 January 2023 → 7 January 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
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 adjusted with the VIIRS detections inside the perimeter, which said 9 January 2023 to 16 January 2023. 51 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.