How long did the Yero'o fire last?

GWIS (Copernicus) dates it between 5 July 2017 and 15 July 2017: 11 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 2,607 hectares (26.1 km²). It is an estimate: official national figures may differ.

Which municipalities burned?

The fire only entered Yero'o (2,599 ha, 0.3 %).

What was the weather like?

During the fire the temperature reached 33.0 °C, humidity dropped to 18 % and gusts hit 52 km/h. The fire danger index (FWI) reached 40, class Very high.

Where does this data come from?

From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Mongolia (geoBoundaries). It is not an official report.

MN · Mongolia · 2017-07-05 → 2017-07-15

Yero'o fire, 5 July 2017 Yero'o

Out · last measured on 15 Jul 2017

The fire started on 5 July 2017 in Yero'o, Mongolia, and satellites saw it burning for 11 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 2,607 hectares from heat detections, spread across a single municipality.

It is the 16th largest in Selenge since 2016 (of 17 with a page). Number 27 in Mongolia in 2017, of 36.

Compare with…

Suggestions: Yero'o · 2017 Yero'o · 2017 Yero'o · 2025

We have the GWIS perimeter for this fire, but the VIIRS sensors did not capture it in enough detail: no day-by-day evolution, but the split by municipality is there.

Burnt area: 2,607ha; GWIS perimeter (Copernicus)
Duration: 11days; 5 Jul 2017 – 15 Jul 2017
Municipalities hit: 1; districts
Started on: 5 Jul; 2017
Danger at start: 24; High · FWI index

The weather it burned in

33°high

52km/h · peak gust

18%lowest humidity

It had gone one day without rain (1 mm or more) when it started. Rain came after the fire: 1.1 mm on 16 Jul.

This area had burned before

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

How big is it?

It burned the equivalent of 1.6% of the area of London (26 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

Yero'o where it started

2,599 ha

0.3 %

Burnt area inside each municipality, from crossing the GWIS 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.

People and buildings inside the perimeter

GHSL 2015

Built-up area< 0.1 ha

Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (GHSL 2015, satellite-based estimate).

This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned.

Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu

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 Jul	24.4 °C	27 %	29 km/h	0.0 mm	High 24
6 Jul	25.6 °C	27 %	28 km/h	0.0 mm	High 27
7 Jul	24.0 °C	43 %	52 km/h	0.0 mm	High 31
8 Jul	23.4 °C	22 %	42 km/h	0.0 mm	High 32
9 Jul	27.3 °C	18 %	35 km/h	0.0 mm	High 35
10 Jul	23.7 °C	27 %	36 km/h	0.0 mm	High 34
11 Jul	29.3 °C	21 %	27 km/h	0.0 mm	High 33
12 Jul	26.2 °C	28 %	43 km/h	0.0 mm	Very high 38
13 Jul	27.3 °C	22 %	23 km/h	0.0 mm	High 30
14 Jul	32.2 °C	18 %	32 km/h	0.0 mm	Very high 39
15 Jul	33.0 °C	21 %	32 km/h	0.0 mm	Very high 40
16 Jul after	24.8 °C	43 %	35 km/h	1.1 mm	Moderate 19

Before and after, from space

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

↔

Before · 28 Jun 2017

After · 22 Jul 2017

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.

Other fires nearby

All fires in Mongolia ›

Frequently asked questions

How long did the Yero'o fire last?: GWIS (Copernicus) dates it between 5 July 2017 and 15 July 2017: 11 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 2,607 hectares (26.1 km²). It is an estimate: official national figures may differ.
Which municipalities burned?: The fire only entered Yero'o (2,599 ha, 0.3 %).
What was the weather like?: During the fire the temperature reached 33.0 °C, humidity dropped to 18 % and gusts hit 52 km/h. The fire danger index (FWI) reached 40, class Very high.
Where does this data come from?: From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Mongolia (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: 105 · 101 · Emergency number and official warnings ›

Satellite cross-check

NASA FIRMS ↗
GWIS · 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.

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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?

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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 105 · 101.

How we know this

Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
Dates from the perimeter: the VIIRS detections inside it did not change them. No 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.
Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2015, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.

How we build fire pages: methodology ›

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.

Where it burned