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UA · Ukraine · –

Olevsk fire, 4 April 2020 Олевський район · Olevsk, Yemilchyne

Out · last detection 10 Apr 2020, 10:52 UTC

The fire started on 4 April 2020 in Olevsk, Ukraine, and satellites saw it burning for 7 days. Copernicus mapped a burnt perimeter of 1,572 hectares from satellite imagery, spread across 2 municipalities.

It is the 16th largest in Zhytomyr Oblast since 2016 (of 179 with a page). Number 26 in Ukraine in 2020, of 132.

Burnt area
1,572ha
Copernicus perimeter
Duration
7days
4 Apr 2020 – 10 Apr 2020
Municipalities hit
2
districts
Started on
4 Apr
2020
Heat detections
57
in a single hotspot: 88 MW
Danger at start
22
High · FWI index
Average daily power
83MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 4 Apr10 Apr
10 Apr 2020

How it evolved, day by day

4 Apr 2020 · 250 MW · 15 5 Apr 2020 · 48 MW · 13 6 Apr 2020 · 51 MW · 10 7 Apr 2020 · 105 MW · 9 8 Apr 2020 · 18 MW · 5 10 Apr 2020 · 27 MW · 5
4 Apr 6 Apr 8 Apr

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

The weather it burned in

22°high
54km/h · peak gust
6%lowest humidity

It had gone 12 days without rain (1 mm or more) when it started. Rain came after the fire: 2.5 mm on 13 Apr.

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 1% of the area of London (16 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. Olevsk Олевський район 41,423 inhabitants · 47.6 km from the centre where it started
    1,059 ha reached on 4 Apr
    0.5 %
  2. Yemilchyne Ємільчинський район 32,629 inhabitants · 43.3 km from the centre
    509 ha reached on 4 Apr
    0.3 %

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

  • Mixed forest60 %
  • Broadleaved forest23 %
  • Coniferous forest11 %
  • Other natural land4.9 %
  • Agricultural areas1.8 %

Land cover inside the perimeter as reported by Copernicus EFFIS (outside the Corine Land Cover area).

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)
4 Apr 11.2 °C 18 % 48 km/h 0.0 mm High 22
5 Apr 11.4 °C 19 % 39 km/h 0.0 mm High 23
6 Apr 16.7 °C 10 % 26 km/h 0.0 mm Moderate 19
7 Apr 19.5 °C 6 % 32 km/h 0.0 mm High 29
8 Apr 18.8 °C 18 % 43 km/h 0.0 mm High 35
9 Apr 22.2 °C 14 % 33 km/h 0.0 mm High 30
10 Apr 11.5 °C 22 % 54 km/h 0.3 mm Very high 42
11 Apr after 12.6 °C 19 % 50 km/h 0.0 mm High 34
12 Apr after 14.3 °C 13 % 31 km/h 0.0 mm High 27
13 Apr after 23.0 °C 20 % 62 km/h 2.5 mm Very high 43

Its twins: fires that started in the same weather

It started with an FWI of 22.5, a minimum humidity of 18% and 12 days without rain. Fires in the area that started in weather like this since 2020: 31.

FWI at the start 22.5
Minimum humidity 18 %
Days without rain 12
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Khoroshiv fire, April 2025
142 ha 3 days FWI 22.3 Min. humidity 17 % 59 km away, in 2025

First rain (1 mm or more) after it ended: 1.1 mm on 25 Apr.

What happened to them

2 days
median duration
156 ha
median area
3 %
went past 1,000 ha
2.0 mm
rain at the end (median; 31 of 31 had it)

It was 10.1 times larger than the median of its twins and lasted 7 days, against 2 days.

Only 1 of its 31 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. All of them had rain in the ten days after the end: the first rainy day brought a median of 2.0 mm.

This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it

How it ended

2.5 mmfirst rain
13 Apr3 days after it ended
54km/h · max. gust

It was considered over on 10 Apr, and on 13 Apr 2.5 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 31 of 31, with a median of 2.0 mm.

Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

How a twin is chosen

  • Same area: fires that have already ended, less than 250 km from this one, since 2020.
  • Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
  • Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
  • Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
  • They are sorted by similarity, and the outlines of the first five are drawn.

How we calculate it

Before and after, from space

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

Before · 28 Mar 2020
After · 17 Apr 2020

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 8 April 2020 the air beside the fire reached 24 µg/m³ of PM2.5. That day averaged 19: 1.2 times the WHO daily guideline (15).

PM2.5 peak24 µg/m³
Days over the guideline2 days
PM1031 µg/m³
2 Apr5 Apr8 Apr11 Apr
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 · 57Every 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 Ukraine

Frequently asked questions

How long did the Olevsk fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 4 April 2020 to 10 April 2020 (7 days). The perimeter dates it from 4 April 2020 to 9 April 2020.
How much area did it burn?
The perimeter Copernicus measured from satellite imagery is 1,572 hectares (15.7 km²). Official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Olevsk (1,059 ha, 0.5 %); Yemilchyne (509 ha, 0.3 %).
Did the fire reach a town?
The fire came within 43.3 km of the centre of Yemilchyne, the closest of the areas it touched. 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 22.2 °C, humidity dropped to 6 % and gusts hit 54 km/h. The fire danger index (FWI) reached 42, class Very high.
Where does this data come from?
From the EFFIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Ukraine (geoBoundaries). It is not an official report.
How did the fires that started in similar weather in this area end?
Fires less than 250 km away that started since 2020 with a similar FWI, humidity and dry spell: 31. Their median duration was 2 days and their median area 156 ha; 3 % went past 1,000 ha. Only 1 of its 31 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. All of them had rain in the ten days after the end: the first rainy day brought a median of 2.0 mm.

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: 101 · 112 · 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.

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 101 · 112.

How we know this
  • Perimeter: EFFIS (Copernicus), mapped on satellite imagery; 2 polygons grouped in this page.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 4 April 2020 to 9 April 2020. 57 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 ADM2 (Public Domain). 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.