Grândola fire, August 2017 Azinheira dos Barros e São Mamede do Sádão, Grândola e Santa Margarida da Serra, Abela
The fire started on 11 August 2017 in Azinheira dos Barros e São Mamede do Sádão, Portugal, and satellites saw it burning for 1 day. Copernicus mapped a burnt perimeter of 2,460 hectares from satellite imagery, spread across 3 municipalities. According to ICNF, it was detected on 10 August 2017 at 15:07 and declared extinguished on 12 August 2017.
Number 30 in Portugal in 2017, of 211.
The power measured by the satellite is low (7.6 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…
Suggestions: Ferreira do Alentejo · 2025Messejana · 2025
- Burnt area
- 2,460ha
- Copernicus perimeter
- Duration
- 1day
- 11 Aug 2017 – 11 Aug 2017
- Municipalities hit
- 3
- freguesias
- Started on
- 11 Aug
- 2017
- Heat detections
- 51
- in a single hotspot: 8 MW
- Danger at start
- 43
- Very high · FWI index
- Average daily power
- 149MW
- detected power per day, on average
Where it burned
How it evolved, day by day
11 Aug 2017 · 149 MW · 51
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 43 days without rain (1 mm or more) when it started.
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).
Lisbon boundary: geoBoundaries · geoBoundaries, DG Territory (CC0 1.0).
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).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
Azinheira dos Barros e São Mamede do Sádão 543 inhabitants · 2.9 km from the centre where it started2,238 ha reached on 11 Aug13 %
-
Grândola e Santa Margarida da Serra 10,303 inhabitants · 11.8 km from the centre221 ha reached on 11 Aug0.5 %
-
Abela 836 inhabitants · 8.1 km from the centre4 ha0.0 %
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
- Agricultural areas53 %
- Scrub and transitional woodland30 %
- Broadleaved forest16 %
- Other natural land1.0 %
Land cover inside the perimeter according to Corine Land Cover, as reported by Copernicus.
Official record
According to ICNF, this fire started on 10 August 2017 and burned 2,357 ha (the satellite measured 2,460 ha).
- Grândola Azinheira Dos Barros e São Mamede do Sádão 10 August 2017 · 15:07 2,357 ha · extinguished on 12 August 2017 · 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) |
|---|---|---|---|---|---|
| 11 Aug | 35.6 °C | 12 % | 45 km/h | 0.0 mm | Very high 43 |
| 12 Aug after | 35.1 °C | 15 % | 41 km/h | 0.0 mm | Very high 40 |
| 13 Aug after | 32.3 °C | 24 % | 36 km/h | 0.0 mm | Extreme 53 |
| 14 Aug after | 33.3 °C | 25 % | 40 km/h | 0.0 mm | Very high 43 |
| 15 Aug after | 32.2 °C | 27 % | 45 km/h | 0.0 mm | Very high 41 |
| 16 Aug after | 31.8 °C | 30 % | 42 km/h | 0.0 mm | Extreme 53 |
| 17 Aug after | 35.5 °C | 25 % | 51 km/h | 0.0 mm | Very high 44 |
| 18 Aug after | 35.2 °C | 25 % | 50 km/h | 0.0 mm | Extreme 54 |
| 19 Aug after | 36.1 °C | 26 % | 43 km/h | 0.0 mm | Very high 46 |
| 20 Aug after | 35.4 °C | 32 % | 41 km/h | 0.0 mm | High 35 |
| 21 Aug after | 34.5 °C | 38 % | 44 km/h | 0.0 mm | High 35 |
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 12 August 2017 the air beside the fire reached 37 µg/m³ of PM2.5. That day averaged 22: 1.5 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 · 51Every 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 Grândola fire last?
- Copernicus dates it between 11 August 2017 and 11 August 2017: 1 day between the first and last image with fire. According to ICNF, it was detected on 10 August 2017 at 15:07 and declared extinguished on 12 August 2017.
- How much area did it burn?
- The perimeter Copernicus measured from satellite imagery is 2,460 hectares (24.6 km²). Official national figures may differ.
- Which municipalities burned?
- The fire entered 3 municipalities: Azinheira dos Barros e São Mamede do Sádão (2,238 ha, 13 %); Grândola e Santa Margarida da Serra (221 ha, 0.5 %); Abela (4 ha, 0.0 %).
- Did the fire reach a town?
- The fire started in Azinheira dos Barros e São Mamede do Sádão and came within 2.9 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 35.6 °C, humidity dropped to 12 % and gusts hit 45 km/h. The fire danger index (FWI) reached 43, class Very 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. 51 Suomi-NPP VIIRS detections on those dates.
- Compared with ICNF: 2,357 official ha against 2,460 ha of perimeter; they agree within 25%.
- Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.
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.