Arnoia fire, August 2025 Arnoia, Rebordelo
The fire started on 3 August 2025 in Arnoia, Portugal, and satellites saw it burning for 3 days. Copernicus mapped a burnt perimeter of 207 hectares from satellite imagery, spread across 2 municipalities.
It is the 7th largest in Celorico de Basto since 2016 (of 12 with a page). Number 60 in Portugal in 2025, of 85.
- Burnt area
- 207ha
- Copernicus perimeter
- Duration
- 3days
- 3 Aug 2025 – 5 Aug 2025
- Municipalities hit
- 2
- freguesias
- Started on
- 3 Aug
- 2025
- Heat detections
- 24
- in a single hotspot: 35 MW
- Danger at start
- 32
- High · FWI index
- Average daily power
- 118MW
- 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 14 days without rain (1 mm or more) when it started.
This area had burned before
5% of the perimeter overlaps earlier fires recorded since 2016: 10 ha in 2017.
What happened to each town
-
207 ha reached on 3 Aug11 %
-
Rebordelo 267 inhabitants · 0.5 km from the centre0 ha reached on 3 Aug0.0 %
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
- Scrub and transitional woodland93 %
- Mixed forest4.3 %
- Agricultural areas2.9 %
Land cover inside the perimeter according to Corine Land Cover, as reported by Copernicus.
People and buildings inside the perimeter
GHSL 2025Inside 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) |
|---|---|---|---|---|---|
| 4 Aug | 35.8 °C | 28 % | 30 km/h | 0.0 mm | High 32 |
| 5 Aug | 37.4 °C | 26 % | 24 km/h | 0.0 mm | High 33 |
| 6 Aug after | 32.9 °C | 40 % | 31 km/h | 0.0 mm | High 30 |
| 7 Aug after | 33.4 °C | 39 % | 31 km/h | 0.0 mm | High 31 |
| 8 Aug after | 32.9 °C | 45 % | 32 km/h | 0.4 mm | High 29 |
| 9 Aug after | 34.8 °C | 38 % | 28 km/h | 0.0 mm | High 28 |
| 10 Aug after | 35.3 °C | 35 % | 40 km/h | 0.0 mm | High 32 |
| 11 Aug after | 34.9 °C | 32 % | 19 km/h | 0.0 mm | High 29 |
| 12 Aug after | 33.7 °C | 37 % | 36 km/h | 0.0 mm | High 33 |
| 13 Aug after | 32.4 °C | 41 % | 27 km/h | 0.7 mm | High 23 |
| 14 Aug after | 34.7 °C | 34 % | 28 km/h | 0.0 mm | High 27 |
| 15 Aug after | 32.2 °C | 39 % | 37 km/h | 0.0 mm | High 30 |
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.
The smoke
CAMS · CopernicusOn 7 August 2025 the air beside the fire reached 208 µg/m³ of PM2.5. That day averaged 93: 6.2 times the WHO daily guideline (15).
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 · 24Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 2,682 haCelorico de Basto Codeçoso14 September 2024 · 6 days · 7 km away
- 6,087 haVila Real Vila Marim3 August 2025 · 13 days · 16 km away
- 6,845 haUnião das Freguesias de Campelo e Ovil e Loivos do MonteSeptember 2024 · 3 days · 18 km away
- 5,850 haVila Real Adoufe e Vilarinho de Samardã21 August 2022 · 6 days · 23 km away
- 2,869 haRibeira de Pena AlvãoSeptember 2016 · 7 days · 24 km away
- 2,728 haCabeceiras de Basto Cavez14 September 2024 · 6 days · 24 km away
Frequently asked questions
- How long did the Arnoia fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 3 August 2025 to 5 August 2025 (3 days). The perimeter dates it from 4 August 2025 to 5 August 2025.
- How much area did it burn?
- The perimeter Copernicus measured from satellite imagery is 207 hectares (2.1 km²). Official national figures may differ.
- Which municipalities burned?
- The fire entered 2 municipalities: Arnoia (207 ha, 11 %); Rebordelo (0 ha, 0.0 %).
- Did the fire reach a town?
- The fire came within 0.5 km of the centre of Rebordelo, the closest of the areas it touched. 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 37.4 °C, humidity dropped to 26 % and gusts hit 30 km/h. The fire danger index (FWI) reached 33, class High.
- Where does this data come from?
- From the EFFIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Portugal (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: 112 · Emergency number and official warnings ›
- ICNF · Instituto da Conservação da Natureza e das Florestas ↗
- ANEPC · Proteção Civil ↗
- Fogos.pt (ocorrências em tempo real) ↗
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: EFFIS (Copernicus), mapped on satellite imagery.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 4 August 2025 to 5 August 2025. 24 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.
Where this data comes from
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 (CC0 1.0 Universal (CC0 1.0) Public Domain Dedication). 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.