Pihuamo fire, April 2021 Tecalitlán, Pihuamo
The fire started on 21 April 2021 in Pihuamo, Mexico, and satellites saw it burning for 8 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 6,902 hectares from heat detections, spread across 2 municipalities.
It is the 21th largest in Jalisco since 2016 (of 283 with a page). Number 23 in Mexico in 2021, of 295.
Compare with…
- Burnt area
- 6,902ha
- GWIS perimeter (Copernicus)
- Duration
- 8days
- 21 Apr 2021 – 28 Apr 2021
- Municipalities hit
- 2
- municipalities
- Started on
- 21 Apr
- 2021
- Heat detections
- 361
- in a single hotspot: 147 MW
- Danger at start
- 44
- Very high · FWI index
- Average daily power
- 511MW
- detected power per day, on average
Where it burned
How it evolved, day by day
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
It had gone more than two months without rain (1 mm or more) when it started. Rain came after the fire: 1.6 mm on 1 May.
This area had burned before
No earlier perimeters overlap this fire since 2016, when the satellite record begins.
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
-
6,794 ha reached on 21 Apr5.2 %
-
Pihuamo where it started150 ha reached on 21 Apr0.2 %
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 2020Inside the perimeter there were about 0.80 hectares of built-up land and about 50 residents (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
Official record
According to CONAFOR, this fire started on 21 April 2021 and burned 3,937 ha (the satellite measured 6,902 ha). The two figures differ a lot, so these may not be exactly the same fire: take them as nearby records.
- Pihuamo Corralito 21 April 2021 3,937 ha · extinguished on 28 April 2021 · cause: negligence
CONAFOR (Comisión Nacional Forestal), estadística de incendios forestales en datos.gob.mx (CC BY 4.0). This is the agency’s consolidated statistic: it measures the area in its own way, which is why it can differ from the satellite.
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 Apr | 30.5 °C | 12 % | 41 km/h | 0.0 mm | Very high 44 |
| 22 Apr | 30.0 °C | 17 % | 43 km/h | 0.0 mm | Very high 45 |
| 23 Apr | 30.5 °C | 16 % | 44 km/h | 0.0 mm | Very high 46 |
| 24 Apr | 30.1 °C | 24 % | 48 km/h | 0.0 mm | Very high 43 |
| 25 Apr | 30.5 °C | 24 % | 38 km/h | 0.0 mm | Very high 41 |
| 26 Apr | 30.3 °C | 27 % | 43 km/h | 0.0 mm | Very high 39 |
| 27 Apr | 31.3 °C | 23 % | 44 km/h | 0.0 mm | Very high 40 |
| 28 Apr | 30.0 °C | 25 % | 48 km/h | 0.0 mm | Very high 41 |
| 29 Apr after | 29.2 °C | 27 % | 44 km/h | 0.0 mm | Very high 41 |
| 30 Apr after | 29.5 °C | 26 % | 45 km/h | 0.2 mm | Very high 40 |
| 1 May after | 28.8 °C | 29 % | 49 km/h | 1.6 mm | High 22 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
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 · 361Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
Frequently asked questions
- How long did the Pihuamo fire last?
- GWIS (Copernicus) dates it between 21 April 2021 and 28 April 2021: 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 6,902 hectares (69.0 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire entered 2 municipalities: Tecalitlán (6,794 ha, 5.2 %); Pihuamo (150 ha, 0.2 %).
- What was the weather like?
- During the fire the temperature reached 31.3 °C, humidity dropped to 12 % and gusts hit 48 km/h. The fire danger index (FWI) reached 46, class Very 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.
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.
No changes 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
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. 361 Suomi-NPP VIIRS detections on those dates.
- Compared with CONAFOR: 3,937 official ha against 6,902 ha of perimeter; similar, but with reservations.
- 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.
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.