How long did the Arcos de Valdevez fire last?

According to the heat detections seen by satellite inside the perimeter, it burned from 6 August 2016 to 9 August 2016 (4 days). The perimeter dates it from 9 August 2016 to 9 August 2016. According to ICNF, it was detected on 6 August 2016 at 13:15 and declared extinguished on 7 August 2016.

How much area did it burn?

The perimeter Copernicus measured from satellite imagery is 213 hectares (2.1 km²). Official national figures may differ.

Which municipalities burned?

The fire entered 2 municipalities: Portela e Extremo (184 ha, 16 %); União das Freguesias de Alvora e Loureda (29 ha, 2.8 %).

Did the fire reach a town?

The fire started in Portela e Extremo and reached its centre: the point marking it was inside the burnt area or less than 500 metres from it. That does not mean houses burned.

What was the weather like?

During the fire the temperature reached 26.4 °C, humidity dropped to 44 % and gusts hit 59 km/h. The fire danger index (FWI) reached 35, 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.

PT · Portugal · 2016-08-06 → 2016-08-09

Arcos de Valdevez fire, 6 August 2016 Portela e Extremo, União das Freguesias de Alvora e Loureda

Out · last detection 9 Aug 2016, 14:39 UTC

The fire started on 6 August 2016 in Portela e Extremo, Portugal, and satellites saw it burning for 4 days. Copernicus mapped a burnt perimeter of 213 hectares from satellite imagery, spread across 2 municipalities. According to ICNF, it was detected on 6 August 2016 at 13:15 and declared extinguished on 7 August 2016.

It is the 14th largest in Arcos de Valdevez since 2016 (of 29 with a page). Number 106 in Portugal in 2016, of 180.

The power measured by the satellite is low (27.2 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…

Suggestions: Monção · 2017 Arcos de Valdevez · 2016 As Neves · 2017 Ponte da Barca · 2025

Burnt area: 213ha; Copernicus perimeter
Duration: 4days; 6 Aug 2016 – 9 Aug 2016
Municipalities hit: 2; freguesias
Started on: 6 Aug; 2016
Heat detections: 18; in a single hotspot: 27 MW
Danger at start: 35; High · FWI index
Average daily power: 81MW; detected power per day, on average

HOTSPOTS BY DAY 6 Aug9 Aug

Play back 9 Aug 2016

How it evolved, day by day

8 Aug 9 Aug

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

The weather it burned in

26°high

59km/h · peak gust

44%lowest humidity

It had gone 4 days without rain (1 mm or more) when it started. Rain came after the fire: 1.4 mm on 17 Aug.

This area had burned before

No earlier perimeters overlap this fire since 2016, when the satellite record begins.

What happened to each town

Portela e Extremo 323 inhabitants · fire reached the centre where it started

184 ha reached on 8 Aug

16 %
União das Freguesias de Alvora e Loureda 378 inhabitants · 0.9 km from the centre

29 ha

2.8 %

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 land95 %
Agricultural areas2.9 %
Scrub and transitional woodland2.4 %

Land cover inside the perimeter according to Corine Land Cover, as reported by Copernicus.

Official record

According to ICNF, this fire started on 6 August 2016 and burned 206 ha (the satellite measured 213 ha).

Arcos de Valdevez Portela 6 August 2016 · 13:15 206 ha · extinguished on 7 August 2016 · cause: rekindling

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 Aug	26.4 °C	44 %	59 km/h	0.0 mm	High 35
10 Aug after	27.5 °C	30 %	52 km/h	0.0 mm	High 31
11 Aug after	28.8 °C	23 %	34 km/h	0.0 mm	High 31
12 Aug after	29.2 °C	30 %	28 km/h	0.0 mm	High 30
13 Aug after	26.1 °C	33 %	25 km/h	0.0 mm	High 28
14 Aug after	25.3 °C	49 %	22 km/h	0.2 mm	High 22
15 Aug after	24.5 °C	55 %	29 km/h	0.7 mm	Moderate 15
16 Aug after	21.5 °C	53 %	34 km/h	0.0 mm	Moderate 16
17 Aug after	21.1 °C	68 %	34 km/h	1.4 mm	Low 8

Before and after, from space

Drag the line to compare the same ground before the fire and after it.

↔

Before · 30 Jul 2016

After · 16 Aug 2016

Before After

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 11 August 2016 the air beside the fire reached 73 µg/m³ of PM2.5. That day averaged 45: 3.0 times the WHO daily guideline (15).

PM2.5 peak73 µg/m³

Days over the guideline5 days

PM10117 µg/m³

WHO 15

6789101112

Good Fair Moderate Poor Very poor Extremely 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 · 18Every 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 time	Satellite	FRP (MW)	Lat	Lon

Other fires nearby

All fires in Portugal ›

Frequently asked questions

How long did the Arcos de Valdevez fire last?: According to the heat detections seen by satellite inside the perimeter, it burned from 6 August 2016 to 9 August 2016 (4 days). The perimeter dates it from 9 August 2016 to 9 August 2016. According to ICNF, it was detected on 6 August 2016 at 13:15 and declared extinguished on 7 August 2016.
How much area did it burn?: The perimeter Copernicus measured from satellite imagery is 213 hectares (2.1 km²). Official national figures may differ.
Which municipalities burned?: The fire entered 2 municipalities: Portela e Extremo (184 ha, 16 %); União das Freguesias de Alvora e Loureda (29 ha, 2.8 %).
Did the fire reach a town?: The fire started in Portela e Extremo and reached its centre: the point marking it was inside the burnt area or less than 500 metres from it. That does not mean houses burned.
What was the weather like?: During the fire the temperature reached 26.4 °C, humidity dropped to 44 % and gusts hit 59 km/h. The fire danger index (FWI) reached 35, 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 ›

Satellite cross-check

NASA FIRMS ↗
EFFIS · Copernicus ↗

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.

RSS Changes to this page

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?

Dates or duration Place or towns Burned area Name It was not a wildfire Same fire as another page Something else

What really happened?

Your connection to the fire (optional) Email (optional)

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 112.

How we know this

Perimeter: EFFIS (Copernicus), mapped on satellite imagery.
Dates adjusted with the VIIRS detections inside the perimeter, which said 9 August 2016 to 9 August 2016. 18 Suomi-NPP VIIRS detections on those dates.
Compared with ICNF: 206 official ha against 213 ha of perimeter; they agree within 25%.
Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.

How we build fire pages: methodology ›

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.

Where it burned