Skip to content
worldfires
US · United States · →

Post Ca Fire, September 2021 Dawes, Sioux

Out · last detection 18 Sept 2021, 08:33 UTC

The fire started on 13 September 2021 in Dawes, United States, and satellites saw it burning for 6 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 2,249 hectares, spread across 2 counties.

It is the 20th largest in Nebraska since 2016 (of 40 with a page). Number 153 in United States in 2021, of 385.

Compare with…
Burnt area
2,249ha
official perimeter (MTBS / NIFC)
Duration
≈ 6days
13 Sept 2021 – 18 Sept 2021
Counties hit
2
counties
Started on
13 Sept
2021
Heat detections
123
in a single hotspot: 125 MW
Danger at start
40
Very high · FWI index
Average daily power
1.5GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 13 Sept18 Sept
18 Sept 2021

How it evolved, day by day

17 Sept 2021 · 3,026 MW · 121 18 Sept 2021 · 1 MW · 2
17 Sept 18 Sept

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

The weather it burned in

33°high
58km/h · peak gust
10%lowest humidity

It had gone 8 days without rain (1 mm or more) when it started. Rain came after the fire: 4.5 mm on 20 Sept.

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 1.4% of the area of London (22 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. Dawes where it started
    2,225 ha reached on 17 Sept
    0.6 %
  2. 17 ha reached on 17 Sept
    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 area0.20 ha
Residents< 20

Inside the perimeter there were about 0.20 hectares of 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)
13 Sept 25.6 °C 28 % 47 km/h 0.0 mm Very high 40
14 Sept 25.1 °C 34 % 36 km/h 2.9 mm Low 10
15 Sept 30.3 °C 14 % 47 km/h 0.0 mm High 37
16 Sept 32.0 °C 11 % 53 km/h 0.0 mm Extreme 60
17 Sept 19.8 °C 32 % 58 km/h 0.0 mm High 36
18 Sept 32.6 °C 10 % 49 km/h 0.0 mm Extreme 50
19 Sept after 29.6 °C 18 % 48 km/h 0.2 mm Extreme 54
20 Sept after 15.6 °C 39 % 53 km/h 4.5 mm Low 8

Before and after, from space

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

Before · 6 Sept 2021
After · 25 Sept 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 · 123Every 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 Post Ca Fire last?
The official perimeter only gives the start date (13 September 2021). The end comes from the heat detections inside the perimeter: it burned until 18 September 2021 (6 days from 13 September 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 2,249 hectares (22.5 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire entered 2 counties: Dawes (2,225 ha, 0.6 %); Sioux (17 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 32.6 °C, humidity dropped to 10 % and gusts hit 58 km/h. The fire danger index (FWI) reached 60, class Extreme.
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. 123 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.