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Munson Creek Fire, June 2021 Fairbanks North Star, Yukon-Koyukuk

Out · last detection 23 Jul 2021, 22:53 UTC

The fire started on 19 June 2021 in Fairbanks North Star, United States, and satellites saw it burning for 35 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 21,882 hectares, spread across 2 counties.

It is the 44th largest in Alaska since 2016 (of 472 with a page). Number 30 in United States in 2021, of 385.

Burnt area
21,882ha
official perimeter (MTBS / NIFC)
Duration
≈ 35days
19 Jun 2021 – 23 Jul 2021
Counties hit
2
counties
Started on
19 Jun
2021
Heat detections
1,470
in a single hotspot: 362 MW
Danger at start
1
Very low · FWI index
Average daily power
1.1GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 19 Jun23 Jul
23 Jul 2021

How it evolved, day by day

23 Jun 2021 · 678 MW · 6 24 Jun 2021 · 255 MW · 11 30 Jun 2021 · 273 MW · 15 1 Jul 2021 · 3,641 MW · 121 2 Jul 2021 · 1,544 MW · 165 3 Jul 2021 · 16 MW · 3 4 Jul 2021 · 1,410 MW · 96 5 Jul 2021 · 2,776 MW · 161 6 Jul 2021 · 136 MW · 28 10 Jul 2021 · 58 MW · 4 11 Jul 2021 · 54 MW · 12 12 Jul 2021 · 3,994 MW · 132 13 Jul 2021 · 4,842 MW · 230 14 Jul 2021 · 284 MW · 64 15 Jul 2021 · 30 MW · 5 17 Jul 2021 · 13 MW · 5 19 Jul 2021 · 55 MW · 9 20 Jul 2021 · 2,851 MW · 158 21 Jul 2021 · 356 MW · 136 22 Jul 2021 · 182 MW · 108 23 Jul 2021 · 6 MW · 1
23 Jun 3 Jul 13 Jul 23 Jul

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

The weather it burned in

26°high
52km/h · peak gust
17%lowest humidity

It had gone one day without rain (1 mm or more) when it started. Rain came after the fire: 10.3 mm on 24 Jul.

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 14% of the area of London (219 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 county

  1. Fairbanks North Star where it started
    21,649 ha reached on 23 Jun
    1.1 %
  2. 244 ha reached on 14 Jul
    0.0 %

Burnt area inside each county, 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.

People and buildings inside the perimeter

GHSL 2020
Built-up area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (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)

Day High Min. humidity Peak gust Rain Danger (FWI)
19 Jun 18.8 °C 59 % 26 km/h 9.9 mm Very low 1
20 Jun 19.1 °C 51 % 19 km/h 1.5 mm Very low 0
21 Jun 18.2 °C 65 % 31 km/h 3.4 mm Very low 1
22 Jun 21.4 °C 41 % 28 km/h 0.0 mm Very low 2
23 Jun 24.9 °C 33 % 36 km/h 0.0 mm Low 8
24 Jun 22.7 °C 39 % 37 km/h 1.9 mm Moderate 13
25 Jun 19.3 °C 41 % 36 km/h 4.0 mm Very low 1
26 Jun 18.0 °C 41 % 36 km/h 0.0 mm Low 5
27 Jun 18.0 °C 41 % 35 km/h 0.0 mm Low 10
28 Jun 17.7 °C 46 % 26 km/h 0.0 mm Low 9
29 Jun 15.8 °C 47 % 52 km/h 0.1 mm Moderate 17
30 Jun 19.0 °C 42 % 46 km/h 0.0 mm Moderate 15
1 Jul 25.1 °C 29 % 20 km/h 0.0 mm Moderate 14
2 Jul 26.0 °C 17 % 33 km/h 0.3 mm High 26
3 Jul 18.0 °C 40 % 43 km/h 0.8 mm Moderate 12
4 Jul 18.5 °C 38 % 26 km/h 0.0 mm Moderate 13
5 Jul 22.9 °C 32 % 31 km/h 2.1 mm Moderate 18
6 Jul 15.4 °C 63 % 45 km/h 9.4 mm Very low 2
7 Jul 12.0 °C 67 % 33 km/h 1.7 mm Very low 0
8 Jul 14.3 °C 50 % 28 km/h 0.1 mm Very low 1
9 Jul 14.8 °C 51 % 24 km/h 2.6 mm Very low 2
10 Jul 17.3 °C 34 % 31 km/h 0.0 mm Very low 3
11 Jul 18.7 °C 35 % 19 km/h 0.0 mm Low 6
12 Jul 23.4 °C 27 % 19 km/h 0.0 mm Low 11
13 Jul 21.5 °C 40 % 37 km/h 0.0 mm Moderate 16
14 Jul 16.3 °C 54 % 39 km/h 15.7 mm Very low 0
15 Jul 20.0 °C 39 % 19 km/h 2.8 mm Very low 0
16 Jul 22.0 °C 51 % 37 km/h 0.0 mm Very low 1
17 Jul 22.8 °C 43 % 38 km/h 0.0 mm Low 6
18 Jul 17.2 °C 59 % 34 km/h 0.0 mm Low 6
19 Jul 22.7 °C 41 % 22 km/h 0.0 mm Low 7
20 Jul 26.1 °C 37 % 32 km/h 0.2 mm Low 11
21 Jul 21.9 °C 44 % 23 km/h 0.0 mm Low 9
22 Jul 22.9 °C 48 % 20 km/h 2.7 mm Low 9
23 Jul 20.4 °C 61 % 24 km/h 8.1 mm Very low 1
24 Jul after 15.7 °C 65 % 36 km/h 10.3 mm Very low 0

Its twins: fires that started in the same weather

It started with an FWI of 1.3, a minimum humidity of 59% and 1 day without rain. Fires in the area that started in weather like this since 2016: 20.

FWI at the start 1.3
Minimum humidity 59 %
Days without rain 1
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Preacher Fire, July 2023
798 ha 3 days FWI 1.2 Min. humidity 61 % 69 km away, in 2023

First rain (1 mm or more) after it ended: 3.5 mm on 30 Jul.

What happened to them

8 days
median duration
2,618 ha
median area
65 %
went past 1,000 ha
6.9 mm
rain at the end (median; 20 of 20 had it)

It was 8.4 times larger than the median of its twins and lasted 35 days, against 8 days.

Only 1 of its 20 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 6.9 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

10.3 mmfirst rain
24 Julthe day after it ended
52km/h · max. gust

It was considered over on 23 Jul, and on 24 Jul 10.3 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 20 of 20, with a median of 6.9 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 · 12 Jun 2021
After · 30 Jul 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 · 1,470Every 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 United States

Frequently asked questions

How long did the Munson Creek Fire last?
The official perimeter only gives the start date (19 June 2021). The end comes from the heat detections inside the perimeter: it burned until 23 July 2021 (35 days from 19 June 2021), the last day with detections before more than 10 days in a row without any, so it is approximate.
How much area did it burn?
The official perimeter published by United States agencies (MTBS / NIFC) is 21,882 hectares (218.8 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire entered 2 counties: Fairbanks North Star (21,649 ha, 1.1 %); Yukon-Koyukuk (244 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 26.1 °C, humidity dropped to 17 % and gusts hit 52 km/h. The fire danger index (FWI) reached 26, class High.
Where does this data come from?
From the official burnt perimeter of United States agencies (MTBS / NIFC, public domain), NASA FIRMS VIIRS hotspots and the administrative boundaries of United States. 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: 20. Their median duration was 8 days and their median area 2,618 ha; 65 % went past 1,000 ha. Only 1 of its 20 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 6.9 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: 911 · 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 911.

How we know this
  • Perimeter: MTBS (US Geological Survey and US Forest Service), official.
  • The official perimeter has no end date: the end is the last day with VIIRS detections inside the perimeter before a gap of more than 10 days (150 days at most), so it is approximate. 1,470 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 is official and in the public domain. For past years it comes from MTBS (Monitoring Trends in Burn Severity), run by the U.S. Geological Survey and the USDA Forest Service, which map it on Landsat and Sentinel-2 imagery. For the current and last year it comes from WFIGS at the National Interagency Fire Center (NIFC): incident perimeters mapped by fire crews, aircraft and imagery. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. County boundaries come from geoBoundaries ADM2 (Public Domain). The area per county is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ slightly from official figures.