Arcos de Valdevez fire, October 2018 Vale, São Jorge e Ermelo
The fire started on 9 October 2018 in Vale, Portugal, and satellites saw it burning for 2 days. Copernicus mapped a burnt perimeter of 109 hectares from satellite imagery, spread across 2 municipalities. According to ICNF, it was detected on 9 October 2018 at 19:21 and declared extinguished on 10 October 2018.
It is the 25th largest in Arcos de Valdevez since 2016 (of 29 with a page). Number 21 in Portugal in 2018, of 23.
The power measured by the satellite is low (23.6 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
- 109ha
- Copernicus perimeter
- Duration
- 2days
- 9 Oct 2018 – 10 Oct 2018
- Municipalities hit
- 2
- freguesias
- Started on
- 9 Oct
- 2018
- Heat detections
- 8
- in a single hotspot: 24 MW
- Danger at start
- 19
- Moderate · FWI index
- Average daily power
- 44MW
- detected power per day, on average
Where it burned
How it evolved, day by day
10 Oct 2018 · 44 MW · 8
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 29 days without rain (1 mm or more) when it started. Rain came after the fire: 23.7 mm on 11 Oct.
This area had burned before
30% of the perimeter overlaps earlier fires recorded since 2016: 33 ha in 2016.
What happened to each town
-
70 ha reached on 10 Oct4.6 %
-
São Jorge e Ermelo 713 inhabitants · 2.5 km from the centre39 ha reached on 10 Oct1.6 %
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
- Other natural land61 %
- Scrub and transitional woodland34 %
- Mixed forest5.5 %
Land cover inside the perimeter according to Corine Land Cover, as reported by Copernicus.
People and buildings inside the perimeter
GHSL 2020Inside 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
Official record
According to ICNF, this fire started on 9 October 2018 and burned 101 ha (the satellite measured 109 ha).
- Arcos de Valdevez Vale 9 October 2018 · 19:21 101 ha · extinguished on 10 October 2018 · cause: negligence
ICNF (Instituto da Conservação da Natureza e das Florestas). This is the agency’s operational record: its figures may be revised when the year’s statistics are closed.
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) |
|---|---|---|---|---|---|
| 9 Oct | 22.6 °C | 36 % | 31 km/h | 0.0 mm | Moderate 19 |
| 10 Oct | 21.2 °C | 43 % | 58 km/h | 0.1 mm | High 26 |
| 11 Oct after | 18.5 °C | 69 % | 66 km/h | 23.7 mm | Very low 0 |
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 10 October 2018 the air beside the fire reached 12 µg/m³ of PM2.5, but no daily average passed the WHO 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 · 8Every satellite heat detection, one by one, with time, satellite, power and coordinates.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 6,662 haArcos de Valdevez Soajo8 August 2016 · 9 days · 7 km away
- 7,225 haPonte da Barca Entre Ambos-os-Rios, Ermida e GermilJuly 2025 · 11 days · 9 km away
- 3,074 haEntrimoSeptember 2016 · 7 days · 18 km away
- 3,893 haMonção MerufeOctober 2017 · 2 days · 22 km away
- 9,224 haCabração e Moreira do LimaAugust 2016 · 5 days · 27 km away
- 3,240 haMuíñosOctober 2017 · 2 days · 31 km away
Frequently asked questions
- How long did the Arcos de Valdevez fire last?
- Copernicus dates it between 9 October 2018 and 10 October 2018: 2 days between the first and last image with fire. According to ICNF, it was detected on 9 October 2018 at 19:21 and declared extinguished on 10 October 2018.
- How much area did it burn?
- The perimeter Copernicus measured from satellite imagery is 109 hectares (1.1 km²). Official national figures may differ.
- Which municipalities burned?
- The fire entered 2 municipalities: Vale (70 ha, 4.6 %); São Jorge e Ermelo (39 ha, 1.6 %).
- Did the fire reach a town?
- The fire started in Vale and came within 0.6 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 22.6 °C, humidity dropped to 36 % and gusts hit 58 km/h. The fire danger index (FWI) reached 26, 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 from the perimeter: the VIIRS detections inside it did not change them. 8 Suomi-NPP VIIRS detections on those dates.
- Compared with ICNF: 101 official ha against 109 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 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 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.