How long did the Mirninsky Ulus fire last?

According to the heat detections seen by satellite inside the perimeter, it burned from 5 August 2026 to 31 August 2026 (27 days). The perimeter dates it from 5 August 2026 to 30 August 2026.

How much area did it burn?

The perimeter GWIS (Copernicus) rebuilt from heat detections is 54,566 hectares (545.7 km²). It is an estimate: official national figures may differ.

Which municipalities burned?

The fire only entered Mirninsky Ulus (56,519 ha, 0.3 %).

What was the weather like?

During the fire the temperature reached 23.1 °C, humidity dropped to 27 % and gusts hit 48 km/h. The fire danger index (FWI) reached 24, class High.

Where does this data come from?

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

RU · Russia · 2026-08-05 → 2026-08-31

Mirninsky Ulus fire, 5 August 2026 Mirninsky Ulus

Out · last detection 1 Sept 2026, 04:42 UTC

The fire started on 5 August 2026 in Mirninsky Ulus, Russia, and satellites saw it burning for 27 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 54,566 hectares from heat detections, spread across a single municipality.

It is the 75th largest in Sakha Republic since 2016 (of 1422 with a page). Number 20 in Russia in 2026, of 417.

Compare with…

Burnt area: 54,566ha; GWIS perimeter (Copernicus)
Duration: 27days; 5 Aug 2026 – 31 Aug 2026
Municipalities hit: 1; districts
Started on: 5 Aug; 2026
Heat detections: 8,382; in a single hotspot: 530 MW
Danger at start: 16; Moderate · FWI index
Average daily power: 3.0GW; detected power per day, on average

HOTSPOTS BY DAY 5 Aug31 Aug

Play back 1 Sept 2026

How it evolved, day by day

5 Aug 9 Aug 13 Aug 17 Aug 21 Aug 25 Aug 30 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

23°high

48km/h · peak gust

27%lowest humidity

It had gone 15 days without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 31 Aug.

This area had burned before

0% of the perimeter overlaps earlier fires recorded since 2016: 121 ha in 2020.

How big is it?

It burned the equivalent of 34% of the area of London (546 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

Mirninsky Ulus where it started

56,519 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 2025

Built-up area< 0.1 ha

Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (GHSL 2025, 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. The GHSL 2025 epoch is a projection made from 2020 and earlier data.

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 Aug	21.2 °C	32 %	24 km/h	0.0 mm	Moderate 16
6 Aug	23.1 °C	27 %	44 km/h	0.0 mm	High 24
7 Aug	21.2 °C	41 %	48 km/h	0.4 mm	High 22
8 Aug	23.1 °C	46 %	24 km/h	0.0 mm	Moderate 16
9 Aug	18.4 °C	39 %	37 km/h	0.0 mm	Moderate 20
10 Aug	18.2 °C	39 %	30 km/h	0.0 mm	Moderate 19
11 Aug	17.6 °C	36 %	34 km/h	0.0 mm	Moderate 20
12 Aug	18.2 °C	34 %	13 km/h	0.0 mm	Moderate 16
13 Aug	16.3 °C	41 %	30 km/h	0.3 mm	Moderate 19
14 Aug	14.4 °C	51 %	27 km/h	0.0 mm	Moderate 16
15 Aug	13.4 °C	52 %	33 km/h	0.0 mm	Moderate 16
16 Aug	18.3 °C	48 %	37 km/h	0.1 mm	Moderate 16
17 Aug	18.5 °C	52 %	38 km/h	1.5 mm	Low 7
18 Aug	17.0 °C	45 %	30 km/h	0.0 mm	Moderate 11
19 Aug	15.5 °C	41 %	23 km/h	0.0 mm	Moderate 13
20 Aug	17.9 °C	34 %	13 km/h	0.0 mm	Moderate 15
21 Aug	19.5 °C	31 %	15 km/h	0.0 mm	Moderate 17
22 Aug	19.0 °C	37 %	22 km/h	0.0 mm	Moderate 18
23 Aug	19.1 °C	33 %	16 km/h	0.0 mm	Moderate 18
24 Aug	21.1 °C	32 %	19 km/h	0.0 mm	Moderate 19
25 Aug	20.6 °C	34 %	22 km/h	0.0 mm	Moderate 20
26 Aug	21.0 °C	33 %	30 km/h	0.0 mm	High 22
27 Aug	20.5 °C	32 %	22 km/h	0.0 mm	Moderate 21
28 Aug	19.8 °C	37 %	19 km/h	0.0 mm	Moderate 20
29 Aug	17.4 °C	56 %	25 km/h	1.5 mm	Low 7
30 Aug	19.8 °C	42 %	37 km/h	0.0 mm	Moderate 16
31 Aug	21.6 °C	46 %	44 km/h	1.0 mm	Moderate 14

Before and after, from space

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

↔

Before · 29 Jul 2026

After · 7 Sept 2026

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.

The smoke

CAMS · Copernicus

On 28 August 2026 the air beside the fire reached 3,256 µg/m³ of PM2.5. That day averaged 2,260: 151 times the WHO daily guideline (15).

PM2.5 peak3,256 µg/m³

Days over the guideline29 days

PM103,144 µg/m³

Optical depth5.70

WHO 15

34567891011121314151617181920212223242526272829303112

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 · 8,382Every 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 time	Satellite	FRP (MW)	Lat	Lon

Frequently asked questions

How long did the Mirninsky Ulus fire last?: According to the heat detections seen by satellite inside the perimeter, it burned from 5 August 2026 to 31 August 2026 (27 days). The perimeter dates it from 5 August 2026 to 30 August 2026.
How much area did it burn?: The perimeter GWIS (Copernicus) rebuilt from heat detections is 54,566 hectares (545.7 km²). It is an estimate: official national figures may differ.
Which municipalities burned?: The fire only entered Mirninsky Ulus (56,519 ha, 0.3 %).
What was the weather like?: During the fire the temperature reached 23.1 °C, humidity dropped to 27 % and gusts hit 48 km/h. The fire danger index (FWI) reached 24, class High.
Where does this data come from?: From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Russia (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 ›

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.

Report an error

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?

Your connection to the fire (optional) Email (optional)

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.

How we know this

Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery; 2 polygons grouped in this page.
Dates adjusted with the VIIRS detections inside the perimeter, which said 5 August 2026 to 30 August 2026. 8,382 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 2025, 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 (Open Data Commons Open Database License 1.0). 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