The fire started on 29 March 2023 in Piloña, Spain, and satellites saw it burning for 3 days. Copernicus mapped a burnt perimeter of 509 hectares from satellite imagery, spread across 2 municipalities. According to EGIF (MITECO), it was detected on 29 March 2023 at 15:58 and declared extinguished on 9 April 2023.
It is the 24th largest in Asturias since 2016 (of 225 with a page). Number 22 in Spain in 2023, of 124.
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings ›
Weather during the fire
model
23.4°C · 30% RH
High of 23.4 °C and minimum humidity of 30% on 29 March 2023; gusts of 61 km/h on 31 March 2023.
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
ⓘThis page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
· reconstructedofficial
Matched with the official EGIF (MITECO) record
Matches: 420 ha in the official record (records: 1).
A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire pilona-2023-03-3.csv · daily, no individual hotspots
fecha
focos_viirs
frp_mw
tmax_c
tmin_c
hr_min_pct
viento_max_kmh
racha_max_kmh
precip_mm
fwi
clase_fwi
dentro_del_incendio
2023-03-29
0
0
23.4
11.9
30
14.2
58.7
0.1
7
bajo
1
2023-03-30
10
93
19.5
8.7
40
14.7
51.5
0
7.5
bajo
1
2023-03-31
19
341
16.5
10
43
20.2
60.8
0
8.4
bajo
1
2023-04-01
0
0
11.5
6.2
67
14.9
55.8
6.8
0.1
muy_bajo
0
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: EFFIS (Copernicus), NASA FIRMS (VIIRS), EGIF (MITECO), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0), GHSL (JRC). Open-Meteo.com · How we build fire pages: methodology
Burnt area
509ha
Copernicus perimeter
Duration
3days
29 Mar 2023 – 31 Mar 2023
Municipalities hit
2
municipalities
Started on
29 Mar
2023
Heat detections
29
in a single hotspot: 33 MW
Danger at start
7
Low · FWI index
Average daily power
217MW
detected power per day, on average
Where it burned
HOTSPOTS BY DAY
29 Mar31 Mar
Play back31 Mar 2023
How it evolved, day by day
30 Mar31 Mar
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
23°high
61km/h · peak gust
30%lowest humidity
It had gone 2 days without rain (1 mm or more) when it started. Rain came after the fire: 6.8 mm on 1 Apr.
This area had burned before
3% of the perimeter overlaps earlier fires recorded since 2016: 3 ha in 2019, 12 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 13 ha that had burned before.
How big is it?
It burned the equivalent of 0.3% of the area of London (5.1 km² against 1,583 km²).
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
It burned the equivalent of 0.8% of the area of Madrid (5.1 km² against 604 km²).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
It burned the equivalent of 4.8% of the area of Paris (5.1 km² against 105 km²).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
It burned the equivalent of 0.6% of the area of Berlin (5.1 km² against 892 km²).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
Fire perimeterLondon
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
Piloña6,716 inhabitants · 6.3 km from the centrewhere it started
Burnt area inside each municipality, from crossing the official 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.
What burned
Coniferous forest41 %
Other natural land38 %
Broadleaved forest15 %
Scrub and transitional woodland6.3 %
Agricultural areas0.8 %
Land cover inside the perimeter according to Corine Land Cover, as reported by Copernicus.
People and buildings inside the perimeter
GHSL 2025
Built-up area0.14ha
Residents< 20
Inside the perimeter there were about 0.14 hectares of 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.
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)
It was 3.1 times larger than the median of its twins and lasted 3 days, against 2 days.
Only 2 of its 32 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. All of them had rain in the ten days after the end: the first rainy day brought a median of 4.3 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
6.8 mmfirst rain
1 Aprthe day after it ended
61km/h · max. gust
It was considered over on 31 Mar, and on 1 Apr 6.8 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 32 of 32, with a median of 4.3 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.
Drag the line to compare the same ground before the fire and after it.
↔
Before · 22 Mar 2023
After · 7 Apr 2023
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
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 1 April 2023 the air beside the fire reached 56 µg/m³ of PM2.5. That day averaged 33: 2.2 times the WHO daily guideline (15).
PM2.5 peak56µg/m³
Days over the guideline4days
PM1070µg/m³
Optical depth0.80
WHO 15
27 Mar29 Mar31 Mar2 Apr
GoodFairModeratePoorVery poorExtremely 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· 29Every satellite heat detection, one by one, with time, satellite, power and coordinates.›
⬇ Download CSVTimes in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
Copernicus dates it between 29 March 2023 and 31 March 2023: 3 days between the first and last image with fire. According to EGIF (MITECO), it was detected on 29 March 2023 at 15:58 and declared extinguished on 9 April 2023.
How much area did it burn?
The perimeter Copernicus measured from satellite imagery is 509 hectares (5.1 km²). Official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Piloña (402 ha, 1.4 %); Nava (107 ha, 1.1 %).
Did the fire reach a town?
The fire started in Piloña and came within 6.3 km of its centre. That is the distance from the perimeter, or the nearest hotspot, to the point marking the centre; it does not mean it entered the houses.
What was the weather like?
During the fire the temperature reached 23.4 °C, humidity dropped to 30 % and gusts hit 61 km/h. The fire danger index (FWI) reached 8, class Low.
Where does this data come from?
From the EFFIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Spain (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: 32. Their median duration was 2 days and their median area 166 ha; 6 % went past 1,000 ha. Only 2 of its 32 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. All of them had rain in the ten days after the end: the first rainy day brought a median of 4.3 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.
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 errorHow we know this›
Perimeter: EFFIS (Copernicus), mapped on satellite imagery.
Dates from the perimeter: the VIIRS detections inside it did not change them. 29 Suomi-NPP VIIRS detections on those dates.
Compared with EGIF (MITECO): 420 official ha against 509 ha of perimeter; they agree within 25%.
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.
The perimeter and land cover come from the Copernicus European Forest Fire Information System (EFFIS), measured on MODIS and Sentinel-2 imagery and published under CC BY 4.0. 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 ADM3 (Creative Commons Attribution 4.0 International (CC BY 4.0)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ slightly from each country’s official figure.