Skip to content
worldfires
en
EL · Greece · →

Oichalia fire, August 2021 Οιχαλίας · Megalopolis, Oichalia

Out · last detection 12 Aug 2021, 11:21 UTC

The fire started on 5 August 2021 in Oichalia, Greece, and satellites saw it burning for 8 days. Copernicus mapped a burnt perimeter of 4,688 hectares from satellite imagery, spread across 2 municipalities.

It is the 4th largest in Peloponnese since 2016 (of 40 with a page). Number 7 in Greece in 2021, of 45.

Compare with…

Suggestions: Megalopolis · 2022Megalopolis · 2017Trifylia · 2025Andritsaina-Krestena · 2017

Burnt area
4,688ha
Copernicus perimeter
Duration
8days
5 Aug 2021 – 12 Aug 2021
Municipalities hit
2
municipalities
Started on
5 Aug
2021
Heat detections
268
in a single hotspot: 373 MW
Danger at start
73
Very extreme · FWI index
Average daily power
982MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 5 Aug12 Aug
12 Aug 2021

How it evolved, day by day

5 Aug 2021 · 2,463 MW · 47 6 Aug 2021 · 3,468 MW · 118 7 Aug 2021 · 1,683 MW · 58 8 Aug 2021 · 139 MW · 19 9 Aug 2021 · 18 MW · 6 10 Aug 2021 · 26 MW · 4 11 Aug 2021 · 32 MW · 12 12 Aug 2021 · 24 MW · 4
5 Aug 6 Aug 7 Aug 9 Aug 11 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

39°high
60km/h · peak gust
12%lowest humidity

It had gone 14 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?

10 km
It burned the equivalent of 3% of the area of London (47 km² against 1,583 km²).

London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).

This compares size, not location: both shapes are at the same scale, north up, centred on each other.

What happened to each town

  1. Megalopolis Μεγαλόπολις
    2,960 ha reached on 6 Aug
    4.8 %
  2. Oichalia Οιχαλίας 3,340 inhabitants · 4.8 km from the centre where it started
    1,739 ha reached on 5 Aug
    5.5 %

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 woodland35 %
  • Agricultural areas31 %
  • Sclerophyllous scrub14 %
  • Broadleaved forest7.4 %
  • Other natural land7.4 %
  • Mixed forest3.6 %
  • Artificial surfaces1.7 %

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

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)
5 Aug 39.0 °C 12 % 51 km/h 0.0 mm Very extreme 73
6 Aug 30.8 °C 30 % 60 km/h 0.0 mm Extreme 55
7 Aug 33.2 °C 24 % 48 km/h 0.0 mm Very high 40
8 Aug 33.7 °C 22 % 42 km/h 0.0 mm High 36
9 Aug 35.1 °C 28 % 36 km/h 0.0 mm Very high 46
10 Aug 39.0 °C 19 % 49 km/h 0.0 mm Very high 44
11 Aug 38.0 °C 21 % 37 km/h 0.2 mm Extreme 55
12 Aug 33.1 °C 32 % 52 km/h 0.0 mm Extreme 53
13 Aug after 33.9 °C 23 % 55 km/h 0.0 mm Extreme 63
14 Aug after 32.0 °C 27 % 52 km/h 0.2 mm Very high 44
15 Aug after 32.7 °C 18 % 39 km/h 0.0 mm Very high 49
16 Aug after 32.4 °C 22 % 55 km/h 0.0 mm Very high 40
17 Aug after 32.7 °C 29 % 45 km/h 0.0 mm Extreme 53
18 Aug after 34.7 °C 24 % 46 km/h 0.0 mm Very high 48
19 Aug after 33.1 °C 28 % 47 km/h 0.6 mm Very high 41
20 Aug after 30.1 °C 39 % 40 km/h 0.9 mm High 30

Before and after, from space

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

Before · 29 Jul 2021
After · 19 Aug 2021

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 5 August 2021 the air beside the fire reached 62 µg/m³ of PM2.5. That day averaged 30: 2.0 times the WHO daily guideline (15).

PM2.5 peak62 µg/m³
Days over the guideline9 days
PM1082 µg/m³
3456789101112131415
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 · 268Every 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 timeSatelliteFRP (MW)LatLon

Other fires nearby

All fires in Greece ›

Frequently asked questions

How long did the Oichalia fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 5 August 2021 to 12 August 2021 (8 days). The perimeter dates it from 5 August 2021 to 10 August 2021.
How much area did it burn?
The perimeter Copernicus measured from satellite imagery is 4,688 hectares (46.9 km²). Official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Megalopolis (2,960 ha, 4.8 %); Oichalia (1,739 ha, 5.5 %).
Did the fire reach a town?
The fire started in Oichalia and came within 4.8 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 39.0 °C, humidity dropped to 12 % and gusts hit 60 km/h. The fire danger index (FWI) reached 73, class Very extreme.
Where does this data come from?
From the EFFIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Greece (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 · 199 · Emergency number and official warnings ›

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.

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?

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 · 199.

How we know this
  • Perimeter: EFFIS (Copernicus), mapped on satellite imagery.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 5 August 2021 to 10 August 2021. 268 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.

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.