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AR · Argentina · –

Valle Viejo fire, January 2022 Valle Viejo, Ancasti

Out · last detection 17 Jan 2022, 06:01 UTC

The fire started on 10 January 2022 in Valle Viejo, Argentina, and satellites saw it burning for 8 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 2,535 hectares from heat detections, spread across 2 municipalities.

It is the 15th largest in Catamarca since 2016 (of 38 with a page). Number 195 in Argentina in 2022, of 441.

Burnt area
2,535ha
GWIS perimeter (Copernicus)
Duration
8days
10 Jan 2022 – 17 Jan 2022
Municipalities hit
2
departments
Started on
10 Jan
2022
Heat detections
134
in a single hotspot: 88 MW
Danger at start
14
Moderate · FWI index
Average daily power
280MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 10 Jan17 Jan
17 Jan 2022

How it evolved, day by day

10 Jan 2022 · 8 MW · 2 12 Jan 2022 · 25 MW · 5 13 Jan 2022 · 69 MW · 7 14 Jan 2022 · 1,487 MW · 78 15 Jan 2022 · 271 MW · 24 16 Jan 2022 · 78 MW · 14 17 Jan 2022 · 20 MW · 4
10 Jan 14 Jan 17 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

34°high
56km/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: 20.6 mm on 18 Jan.

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 1.6% of the area of London (25 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. Valle Viejo where it started
    2,118 ha reached on 10 Jan
    3.5 %
  2. 423 ha reached on 14 Jan
    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 area0.38 ha
Residents< 20

Inside the perimeter there were about 0.38 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)

Day High Min. humidity Peak gust Rain Danger (FWI)
10 Jan 32.4 °C 22 % 38 km/h 0.0 mm Moderate 14
11 Jan 33.7 °C 19 % 37 km/h 0.0 mm Moderate 16
12 Jan 32.5 °C 21 % 46 km/h 0.0 mm Moderate 19
13 Jan 32.6 °C 21 % 56 km/h 0.0 mm Moderate 21
14 Jan 33.4 °C 20 % 53 km/h 0.0 mm High 21
15 Jan 33.7 °C 20 % 49 km/h 0.4 mm Moderate 21
16 Jan 34.0 °C 23 % 36 km/h 0.5 mm Moderate 19
17 Jan 28.9 °C 35 % 34 km/h 2.6 mm Very low 5
18 Jan after 18.6 °C 75 % 38 km/h 20.6 mm Very low 0

Its twins: fires that started in the same weather

It started with an FWI of 14.0, a minimum humidity of 22% and 4 days without rain. Fires in the area that started in weather like this since 2016: 22.

FWI at the start 14.0
Minimum humidity 22 %
Days without rain 4
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Capayán fire, August 2017
3,164 ha 5 days FWI 17.3 Min. humidity 23 % 42 km away, in 2017

First rain (1 mm or more) after it ended: 6.8 mm on 11 Aug.

What happened to them

6 days
median duration
3,010 ha
median area
100 %
went past 1,000 ha
3.4 mm
rain at the end (median; 17 of 22 had it)

It burned an area similar to its twins (2,535 ha against a median of 3,010 ha) and lasted 8 days, against 6 days.

In 5 of 22, 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 3.4 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

20.6 mmfirst rain
18 Janthe day after it ended
56km/h · max. gust

It was considered over on 17 Jan, and on 18 Jan 20.6 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 17 of 22, with a median of 3.4 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 · 3 Jan 2022
After · 24 Jan 2022

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 · 134Every 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 Valle Viejo fire last?
GWIS (Copernicus) dates it between 10 January 2022 and 17 January 2022: 8 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 2,535 hectares (25.4 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Valle Viejo (2,118 ha, 3.5 %); Ancasti (423 ha, 0.2 %).
What was the weather like?
During the fire the temperature reached 34.0 °C, humidity dropped to 19 % and gusts hit 56 km/h. The fire danger index (FWI) reached 21, 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: 22. Their median duration was 6 days and their median area 3,010 ha; 100 % went past 1,000 ha. In 5 of 22, 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 3.4 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. 134 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 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.