Skip to content
worldfires
MX · Mexico · –

Ayutla de los Libres fire, April 2018 Ayutla de los Libres, Acatepec, Quechultenango

Out · last detection 21 Apr 2018, 19:11 UTC

The fire started on 16 April 2018 in Ayutla de los Libres, Mexico, and satellites saw it burning for 6 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 2,548 hectares from heat detections, spread across 3 municipalities.

It is the 284th largest in Guerrero since 2016 (of 582 with a page). Number 107 in Mexico in 2018, of 233.

The power measured by the satellite is low (12.1 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Compare with…
Burnt area
2,548ha
GWIS perimeter (Copernicus)
Duration
6days
16 Apr 2018 – 21 Apr 2018
Municipalities hit
3
municipalities
Started on
16 Apr
2018
Heat detections
103
in a single hotspot: 12 MW
Danger at start
29
High · FWI index
Average daily power
53MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 16 Apr21 Apr
21 Apr 2018

How it evolved, day by day

16 Apr 2018 · 11 MW · 3 17 Apr 2018 · 100 MW · 35 18 Apr 2018 · 117 MW · 29 19 Apr 2018 · 26 MW · 6 20 Apr 2018 · 31 MW · 15 21 Apr 2018 · 32 MW · 15
16 Apr 18 Apr 20 Apr

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

The weather it burned in

36°high
52km/h · peak gust
27%lowest humidity

It had gone 3 days without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 25 Apr.

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. Ayutla de los Libres where it started
    2,315 ha reached on 16 Apr
    2.2 %
  2. 234 ha reached on 16 Apr
    0.4 %
  3. 15 ha
    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 2020
Built-up area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable 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)
16 Apr 35.4 °C 30 % 40 km/h 0.2 mm High 29
17 Apr 33.9 °C 33 % 41 km/h 1.4 mm High 22
18 Apr 33.6 °C 37 % 50 km/h 0.0 mm High 28
19 Apr 33.8 °C 34 % 52 km/h 0.0 mm High 30
20 Apr 36.1 °C 27 % 50 km/h 0.0 mm High 34
21 Apr 34.7 °C 35 % 43 km/h 1.2 mm High 24
22 Apr after 35.3 °C 35 % 45 km/h 0.0 mm High 30
23 Apr after 34.7 °C 40 % 39 km/h 0.3 mm High 32
24 Apr after 34.1 °C 37 % 42 km/h 0.5 mm High 28
25 Apr after 36.0 °C 30 % 43 km/h 1.0 mm High 29

Its twins: fires that started in the same weather

It started with an FWI of 29.2, a minimum humidity of 30% and 3 days without rain. Fires in the area that started in weather like this since 2016: 20.

FWI at the start 29.2
Minimum humidity 30 %
Days without rain 3
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Acatepec fire, May 2020
1,577 ha 6 days FWI 31.0 Min. humidity 30 % 3 km away, in 2020

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

What happened to them

9 days
median duration
1,868 ha
median area
100 %
went past 1,000 ha
1.5 mm
rain at the end (median; 12 of 20 had it)

It burned an area similar to its twins (2,548 ha against a median of 1,868 ha) and lasted 6 days, against 9 days.

In 8 of 20, 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 1.5 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

1.0 mmfirst rain
25 Apr4 days after it ended
52km/h · max. gust

It was considered over on 21 Apr, and on 25 Apr 1.0 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 12 of 20, with a median of 1.5 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 · 9 Apr 2018
After · 28 Apr 2018

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 · 103Every 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 Mexico

Frequently asked questions

How long did the Ayutla de los Libres fire last?
GWIS (Copernicus) dates it between 16 April 2018 and 21 April 2018: 6 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 2,548 hectares (25.5 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 3 municipalities: Ayutla de los Libres (2,315 ha, 2.2 %); Acatepec (234 ha, 0.4 %); Quechultenango (15 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 36.1 °C, humidity dropped to 27 % and gusts hit 52 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 Mexico (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: 20. Their median duration was 9 days and their median area 1,868 ha; 100 % went past 1,000 ha. In 8 of 20, 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 1.5 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 · 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.

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. 103 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 4.0 (CC BY 4.0)). 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.