Oeiras fire, 13 July 2021 Oeiras
The fire started on 13 July 2021 in Oeiras, Brazil, and satellites saw it burning for 16 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,188 hectares from heat detections, spread across a single municipality.
It is the 733th largest in Piaui since 2016 (of 803 with a page). Number 749 in Brazil in 2021, of 814.
The power measured by the satellite is low (24.4 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.
- Burnt area
- 3,188ha
- GWIS perimeter (Copernicus)
- Duration
- 16days
- 13 Jul 2021 – 28 Jul 2021
- Municipalities hit
- 1
- municipalities
- Started on
- 13 Jul
- 2021
- Heat detections
- 180
- in a single hotspot: 24 MW
- Danger at start
- 44
- Very high · FWI index
- Energy released
- 711MW
- sum of detected power
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 more than two months 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.
What happened to each town
-
3,210 ha reached on 13 Jul1.2 %
Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance is from the town centre to the nearest fire: staying a kilometre away does not mean it reached the houses.
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) |
|---|---|---|---|---|---|
| 13 Jul | 33.7 °C | 28 % | 48 km/h | 0.0 mm | Very high 44 |
| 14 Jul | 34.2 °C | 30 % | 44 km/h | 0.0 mm | Very high 43 |
| 15 Jul | 32.9 °C | 38 % | 45 km/h | 0.0 mm | Very high 40 |
| 16 Jul | 35.0 °C | 28 % | 40 km/h | 0.0 mm | Very high 40 |
| 17 Jul | 35.5 °C | 26 % | 35 km/h | 0.0 mm | Very high 40 |
| 18 Jul | 35.1 °C | 26 % | 32 km/h | 0.0 mm | Very high 39 |
| 19 Jul | 36.1 °C | 22 % | 30 km/h | 0.0 mm | Very high 42 |
| 20 Jul | 35.4 °C | 29 % | 36 km/h | 0.0 mm | Very high 46 |
| 21 Jul | 34.2 °C | 29 % | 48 km/h | 0.0 mm | Extreme 50 |
| 22 Jul | 33.5 °C | 27 % | 50 km/h | 0.0 mm | Extreme 53 |
| 23 Jul | 33.3 °C | 28 % | 55 km/h | 0.0 mm | Extreme 54 |
| 24 Jul | 34.2 °C | 27 % | 55 km/h | 0.0 mm | Extreme 57 |
| 25 Jul | 33.8 °C | 26 % | 52 km/h | 0.0 mm | Extreme 52 |
| 26 Jul | 34.4 °C | 28 % | 54 km/h | 0.0 mm | Extreme 54 |
| 27 Jul | 35.2 °C | 26 % | 39 km/h | 0.0 mm | Very high 46 |
| 28 Jul | 34.9 °C | 33 % | 37 km/h | 0.0 mm | Very high 42 |
| 29 Jul after | 35.8 °C | 29 % | 21 km/h | 0.0 mm | High 36 |
| 30 Jul after | 37.6 °C | 14 % | 38 km/h | 0.0 mm | Extreme 58 |
| 31 Jul after | 34.8 °C | 29 % | 55 km/h | 0.0 mm | Extreme 56 |
| 1 Aug after | 30.4 °C | 39 % | 60 km/h | 0.0 mm | Very high 47 |
| 2 Aug after | 33.2 °C | 26 % | 52 km/h | 0.0 mm | Very high 49 |
| 3 Aug after | 34.9 °C | 25 % | 46 km/h | 0.0 mm | Very high 45 |
| 4 Aug after | 33.8 °C | 22 % | 43 km/h | 0.0 mm | Very high 46 |
| 5 Aug after | 34.3 °C | 28 % | 46 km/h | 0.0 mm | Very high 48 |
| 6 Aug after | 35.0 °C | 24 % | 52 km/h | 0.0 mm | Extreme 51 |
| 7 Aug after | 33.3 °C | 27 % | 61 km/h | 0.0 mm | Extreme 57 |
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.
Detections table · 180Every 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 Oeiras fire last?
- GWIS (Copernicus) dates it between 13 July 2021 and 28 July 2021: 16 days between the first and last heat detection of the perimeter.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,188 hectares (31.9 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Oeiras (3,210 ha, 1.2 %).
- What was the weather like?
- During the fire the temperature reached 36.1 °C, humidity dropped to 22 % and gusts hit 55 km/h. The fire danger index (FWI) reached 57, class Extreme.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Brazil (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: 193
Satellite cross-check
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
Where this data comes from
The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. 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 ADM2 (Creative Commons Attribution 3.0 Intergovernmental Organisations (CC BY 3.0 IGO)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.