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NP · Nepal · –

Sunkoshi fire, April 2021 Sunkoshi, Siddhicharan, Manebhanjyang

Out · last detection 12 Apr 2021, 20:07 UTC

The fire started on 3 April 2021 in Sunkoshi, Nepal, and satellites saw it burning for 10 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,779 hectares from heat detections, spread across 4 municipalities.

Number 9 in Nepal in 2021, of 39.

Burnt area
3,779ha
GWIS perimeter (Copernicus)
Duration
10days
3 Apr 2021 – 12 Apr 2021
Municipalities hit
4
municipalities
Started on
3 Apr
2021
Heat detections
122
in a single hotspot: 42 MW
Danger at start
20
Moderate · FWI index
Average daily power
105MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 3 Apr12 Apr
12 Apr 2021

How it evolved, day by day

3 Apr 2021 · 145 MW · 21 4 Apr 2021 · 266 MW · 22 5 Apr 2021 · 171 MW · 15 6 Apr 2021 · 159 MW · 36 7 Apr 2021 · 78 MW · 24 8 Apr 2021 · 9 MW · 1 11 Apr 2021 · 1 MW · 1 12 Apr 2021 · 8 MW · 2
4 Apr 7 Apr 11 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

29°high
57km/h · peak gust
21%lowest humidity

It had gone one day without rain (1 mm or more) when it started. Rain came after the fire: 2.1 mm on 15 Apr.

This area had burned before

32% of the perimeter overlaps earlier fires recorded since 2016: 794 ha in 2018, 401 ha in 2019.

How big is it?

10 km
It burned the equivalent of 2.4% of the area of London (38 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. Sunkoshi where it started
    3,354 ha reached on 3 Apr
    23 %
  2. 225 ha reached on 3 Apr
    1.3 %
  3. 193 ha reached on 6 Apr
    1.3 %
  4. 22 ha
    0.2 %

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 2020
Built-up area11 ha
Residents≈ 1,700

Inside the perimeter there were about 11 hectares of built-up land and about 1,700 residents (GHSL 2020, 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)

Started with Strong wind: 19 % of the area in Nepal

Day High Min. humidity Peak gust Rain Danger (FWI)
3 Apr 26.5 °C 22 % 55 km/h 0.2 mm Moderate 20
4 Apr 26.8 °C 22 % 39 km/h 0.0 mm High 23
5 Apr 25.7 °C 29 % 38 km/h 0.0 mm High 23
6 Apr 25.7 °C 39 % 34 km/h 0.0 mm Moderate 20
7 Apr 27.0 °C 46 % 37 km/h 1.4 mm Moderate 15
8 Apr 27.1 °C 49 % 45 km/h 1.5 mm Moderate 15
9 Apr 26.8 °C 36 % 52 km/h 0.5 mm Moderate 13
10 Apr 27.8 °C 29 % 57 km/h 0.2 mm High 23
11 Apr 29.0 °C 21 % 48 km/h 0.0 mm High 29
12 Apr 27.8 °C 25 % 44 km/h 0.2 mm High 29
13 Apr after 28.4 °C 26 % 48 km/h 0.0 mm High 30
14 Apr after 28.5 °C 33 % 40 km/h 0.0 mm High 29
15 Apr after 27.3 °C 45 % 39 km/h 2.1 mm High 24

Its twins: fires that started in the same weather

It started with an FWI of 19.8, a minimum humidity of 22% and 1 day without rain. Fires in the area that started in weather like this since 2016: 16.

FWI at the start 19.8
Minimum humidity 22 %
Days without rain 1
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Chitwan National Park fire, April 2017
2,282 ha 4 days FWI 19.7 Min. humidity 21 % 157 km away, in 2017

First rain (1 mm or more) after it ended: 2.9 mm on 4 May.

What happened to them

11 days
median duration
3,629 ha
median area
12 %
went past 10,000 ha
3.0 mm
rain at the end (median; 14 of 16 had it)

It burned an area similar to its twins (3,779 ha against a median of 3,629 ha) and lasted 10 days, against 11 days.

In 2 of 16, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.0 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

2.1 mmfirst rain
15 Apr3 days after it ended
57km/h · max. gust

It was considered over on 12 Apr, and on 15 Apr 2.1 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 14 of 16, with a median of 3.0 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 2016.
  • 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 · 27 Mar 2021
After · 19 Apr 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.

Detections table · 122Every 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 Nepal

Frequently asked questions

How long did the Sunkoshi fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 3 April 2021 to 12 April 2021 (10 days). The perimeter dates it from 3 April 2021 to 8 April 2021.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,779 hectares (37.8 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 4 municipalities: Sunkoshi (3,354 ha, 23 %); Siddhicharan (225 ha, 1.3 %); Manebhanjyang (193 ha, 1.3 %); Champadevi (22 ha, 0.2 %).
What was the weather like?
During the fire the temperature reached 29.0 °C, humidity dropped to 21 % and gusts hit 57 km/h. The fire danger index (FWI) reached 29, class High.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Nepal (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 2016 with a similar FWI, humidity and dry spell: 16. Their median duration was 11 days and their median area 3,629 ha; 12 % went past 10,000 ha. In 2 of 16, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.0 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 · Emergency number and official warnings

Satellite cross-check

History of this page · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 8 April 2021 → 12 April 2021.

RSS Changes to this page With cross-checks and a citable version

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.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 3 April 2021 to 8 April 2021. 122 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 2020, 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 ADM3 (Creative Commons Attribution-ShareAlike 4.0 International License). 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.