Skip to content
worldfires
en
US · United States · →

Cameron Peak Fire, August 2020 Larimer

Out · last detection 24 Oct 2020, 19:24 UTC

The fire started on 13 August 2020 in Larimer, United States, and satellites saw it burning for 73 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 84,475 hectares, spread across a single county.

It is the largest fire in Colorado since 2016 (of 167 with a page). Number 8 in United States in 2020, of 441.

Compare with…

Suggestions: Alexander Mountain · 2024

Burnt area
84,475ha
official perimeter (MTBS / NIFC)
Duration
≈ 73days
13 Aug 2020 – 24 Oct 2020
Counties hit
1
counties
Started on
13 Aug
2020
Heat detections
9,707
in a single hotspot: 1,740 MW
Danger at start
16
Moderate · FWI index
Average daily power
6.9GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 13 Aug24 Oct
24 Oct 2020

How it evolved, day by day

13 Aug 2020 · 1,026 MW · 9 14 Aug 2020 · 9,366 MW · 211 15 Aug 2020 · 5,015 MW · 259 16 Aug 2020 · 5,566 MW · 381 17 Aug 2020 · 4,272 MW · 191 18 Aug 2020 · 1,547 MW · 164 19 Aug 2020 · 1,381 MW · 131 20 Aug 2020 · 85 MW · 33 21 Aug 2020 · 5,740 MW · 60 22 Aug 2020 · 3,133 MW · 135 23 Aug 2020 · 2,584 MW · 169 24 Aug 2020 · 1,988 MW · 121 25 Aug 2020 · 223 MW · 59 26 Aug 2020 · 33 MW · 8 27 Aug 2020 · 89 MW · 10 28 Aug 2020 · 5 MW · 3 2 Sept 2020 · 128 MW · 6 3 Sept 2020 · 2,377 MW · 25 4 Sept 2020 · 760 MW · 59 5 Sept 2020 · 3,648 MW · 60 6 Sept 2020 · 99,945 MW · 1183 7 Sept 2020 · 85,146 MW · 1679 14 Sept 2020 · 18 MW · 2 15 Sept 2020 · 62 MW · 7 16 Sept 2020 · 35 MW · 7 17 Sept 2020 · 68 MW · 6 18 Sept 2020 · 98 MW · 6 20 Sept 2020 · 536 MW · 40 21 Sept 2020 · 219 MW · 47 22 Sept 2020 · 43 MW · 22 23 Sept 2020 · 85 MW · 11 24 Sept 2020 · 790 MW · 24 25 Sept 2020 · 6,317 MW · 146 26 Sept 2020 · 22,650 MW · 564 27 Sept 2020 · 398 MW · 132 28 Sept 2020 · 75 MW · 8 29 Sept 2020 · 834 MW · 42 30 Sept 2020 · 648 MW · 85 1 Oct 2020 · 172 MW · 21 2 Oct 2020 · 512 MW · 15 3 Oct 2020 · 30 MW · 5 4 Oct 2020 · 616 MW · 18 5 Oct 2020 · 3,368 MW · 95 6 Oct 2020 · 1,208 MW · 53 7 Oct 2020 · 2,169 MW · 85 8 Oct 2020 · 8,398 MW · 127 9 Oct 2020 · 5,176 MW · 75 10 Oct 2020 · 441 MW · 71 11 Oct 2020 · 289 MW · 107 12 Oct 2020 · 15 MW · 2 13 Oct 2020 · 146 MW · 8 14 Oct 2020 · 89,307 MW · 1203 15 Oct 2020 · 400 MW · 100 16 Oct 2020 · 16,932 MW · 206 17 Oct 2020 · 17,429 MW · 1012 18 Oct 2020 · 538 MW · 31 19 Oct 2020 · 741 MW · 42 20 Oct 2020 · 480 MW · 76 21 Oct 2020 · 1,209 MW · 89 22 Oct 2020 · 489 MW · 61 24 Oct 2020 · 1,041 MW · 100
13 Aug 22 Aug 4 Sept 6 Sept 20 Sept 29 Sept 8 Oct 17 Oct

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

The weather it burned in

27°high
99km/h · peak gust
11%lowest humidity

It had gone 2 days without rain (1 mm or more) when it started. Rain came after the fire: 20.8 mm on 25 Oct.

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 53% of the area of London (845 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. Larimer where it started
    84,566 ha reached on 13 Aug
    12 %

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 area18 ha
Residents≈ 500

Inside the perimeter there were about 18 hectares of built-up land and about 500 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)

Day High Min. humidity Peak gust Rain Danger (FWI)
13 Aug 23.3 °C 14 % 29 km/h 0.0 mm Moderate 16
14 Aug 23.3 °C 13 % 34 km/h 0.0 mm Moderate 19
15 Aug 23.8 °C 13 % 28 km/h 0.0 mm Moderate 19
16 Aug 22.9 °C 18 % 42 km/h 0.0 mm Moderate 21
17 Aug 21.8 °C 31 % 32 km/h 2.9 mm Very low 3
18 Aug 24.4 °C 20 % 38 km/h 0.1 mm Moderate 13
19 Aug 22.1 °C 25 % 40 km/h 1.4 mm Low 8
20 Aug 20.2 °C 33 % 41 km/h 4.0 mm Very low 2
21 Aug 22.6 °C 20 % 36 km/h 0.0 mm Low 10
22 Aug 24.8 °C 13 % 34 km/h 0.0 mm Moderate 20
23 Aug 23.2 °C 22 % 32 km/h 0.9 mm Moderate 14
24 Aug 24.0 °C 21 % 32 km/h 1.7 mm Low 10
25 Aug 23.9 °C 22 % 38 km/h 0.0 mm Moderate 17
26 Aug 22.4 °C 26 % 41 km/h 4.0 mm Very low 3
27 Aug 22.5 °C 27 % 30 km/h 2.0 mm Very low 4
28 Aug 14.5 °C 53 % 40 km/h 12.6 mm Very low 0
29 Aug 16.9 °C 36 % 41 km/h 0.6 mm Very low 1
30 Aug 20.2 °C 23 % 63 km/h 0.5 mm Low 9
31 Aug 16.8 °C 27 % 45 km/h 4.0 mm Very low 1
1 Sept 17.6 °C 24 % 35 km/h 0.0 mm Low 5
2 Sept 21.9 °C 18 % 41 km/h 0.0 mm Moderate 13
3 Sept 21.7 °C 23 % 51 km/h 0.3 mm Moderate 15
4 Sept 20.3 °C 26 % 31 km/h 1.2 mm Low 7
5 Sept 26.9 °C 11 % 27 km/h 0.0 mm Moderate 18
6 Sept 24.2 °C 12 % 50 km/h 0.0 mm High 24
7 Sept 20.9 °C 11 % 59 km/h 8.7 mm Very low 2
8 Sept -0.6 °C 91 % 56 km/h 32.2 mm Very low 0
9 Sept -2.8 °C 83 % 32 km/h 1.5 mm Very low 0
10 Sept 2.3 °C 71 % 31 km/h 0.8 mm Very low 0
11 Sept 4.9 °C 50 % 56 km/h 0.2 mm Very low 0
12 Sept 13.4 °C 28 % 52 km/h 0.0 mm Very low 1
13 Sept 18.1 °C 20 % 34 km/h 0.0 mm Very low 4
14 Sept 19.5 °C 22 % 27 km/h 0.5 mm Low 8
15 Sept 19.8 °C 18 % 34 km/h 0.0 mm Moderate 12
16 Sept 14.0 °C 38 % 31 km/h 0.0 mm Low 10
17 Sept 18.2 °C 21 % 36 km/h 0.0 mm Moderate 12
18 Sept 16.6 °C 28 % 27 km/h 0.5 mm Moderate 12
19 Sept 18.3 °C 22 % 37 km/h 0.8 mm Low 10
20 Sept 16.5 °C 27 % 47 km/h 0.8 mm Low 10
21 Sept 17.8 °C 26 % 23 km/h 0.3 mm Low 11
22 Sept 17.2 °C 26 % 25 km/h 1.7 mm Very low 4
23 Sept 17.3 °C 23 % 42 km/h 0.1 mm Low 11
24 Sept 20.5 °C 20 % 32 km/h 0.0 mm Moderate 16
25 Sept 19.6 °C 18 % 46 km/h 0.0 mm Moderate 18
26 Sept 16.9 °C 23 % 66 km/h 0.0 mm High 22
27 Sept 5.8 °C 44 % 41 km/h 7.0 mm Very low 0
28 Sept 8.1 °C 20 % 38 km/h 0.0 mm Very low 2
29 Sept 17.2 °C 19 % 42 km/h 0.0 mm Low 8
30 Sept 13.3 °C 28 % 40 km/h 0.0 mm Low 10
1 Oct 11.5 °C 33 % 32 km/h 0.0 mm Low 8
2 Oct 14.9 °C 19 % 41 km/h 0.0 mm Moderate 15
3 Oct 11.5 °C 28 % 38 km/h 0.0 mm Moderate 13
4 Oct 17.6 °C 19 % 36 km/h 0.0 mm Moderate 16
5 Oct 17.0 °C 15 % 57 km/h 0.0 mm Moderate 19
6 Oct 19.4 °C 14 % 37 km/h 0.0 mm Moderate 20
7 Oct 18.0 °C 14 % 32 km/h 0.0 mm Moderate 20
8 Oct 19.0 °C 11 % 29 km/h 0.0 mm High 22
9 Oct 17.2 °C 16 % 40 km/h 0.0 mm High 22
10 Oct 17.0 °C 16 % 36 km/h 0.0 mm Moderate 21
11 Oct 10.7 °C 28 % 86 km/h 1.8 mm Low 10
12 Oct 10.8 °C 19 % 85 km/h 0.0 mm Moderate 18
13 Oct 13.9 °C 20 % 69 km/h 0.0 mm Moderate 19
14 Oct 11.6 °C 18 % 99 km/h 0.0 mm High 29
15 Oct 4.3 °C 20 % 56 km/h 0.4 mm Moderate 19
16 Oct 10.0 °C 23 % 77 km/h 0.0 mm High 23
17 Oct 9.1 °C 24 % 86 km/h 0.0 mm High 26
18 Oct 7.0 °C 48 % 44 km/h 0.0 mm Moderate 16
19 Oct 10.6 °C 27 % 67 km/h 0.0 mm Moderate 16
20 Oct 10.3 °C 28 % 73 km/h 0.0 mm Moderate 18
21 Oct 14.3 °C 19 % 54 km/h 0.0 mm Moderate 19
22 Oct 3.9 °C 36 % 46 km/h 1.9 mm Very low 4
23 Oct -4.1 °C 54 % 44 km/h 0.1 mm Very low 4
24 Oct 6.2 °C 30 % 68 km/h 0.2 mm Low 8
25 Oct after -7.5 °C 82 % 38 km/h 20.8 mm Very low 0

Before and after, from space

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

Before · 6 Aug 2020
After · 31 Oct 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.

Detections table · 9,707Every 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 Cameron Peak Fire last?
The official perimeter only gives the start date (13 August 2020). The end comes from the heat detections inside the perimeter: it burned until 24 October 2020 (73 days from 13 August 2020), 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 84,475 hectares (844.8 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire only entered Larimer (84,566 ha, 12 %).
What was the weather like?
During the fire the temperature reached 26.9 °C, humidity dropped to 11 % and gusts hit 99 km/h. The fire danger index (FWI) reached 29, 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.

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.

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?

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. 9,707 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.