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Elliot Fire, August 2023 Siskiyou

Out · last detection 23 Aug 2023, 21:38 UTC

The fire started on 15 August 2023 in Siskiyou, United States, and satellites saw it burning for 9 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 5,603 hectares, spread across a single county.

It is the 123th largest in California since 2016 (of 442 with a page). Number 29 in United States in 2023, of 305.

Compare with…
Burnt area
5,603ha
official perimeter (MTBS / NIFC)
Duration
≈ 9days
15 Aug 2023 – 23 Aug 2023
Counties hit
1
counties
Started on
15 Aug
2023
Heat detections
201
in a single hotspot: 49 MW
Danger at start
46
Very high · FWI index
Average daily power
159MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 15 Aug23 Aug
23 Aug 2023

How it evolved, day by day

16 Aug 2023 · 49 MW · 10 17 Aug 2023 · 65 MW · 16 18 Aug 2023 · 134 MW · 22 19 Aug 2023 · 428 MW · 65 20 Aug 2023 · 252 MW · 73 23 Aug 2023 · 27 MW · 15
16 Aug 17 Aug 18 Aug 19 Aug 20 Aug 23 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

40°high
51km/h · peak gust
19%lowest humidity

It had gone 56 days without rain (1 mm or more) when it started. Rain came after the fire: 1.4 mm on 24 Aug.

This area had burned before

16% of the perimeter overlaps earlier fires recorded since 2016: 887 ha in 2016.

How big is it?

10 km
It burned the equivalent of 3.5% of the area of London (56 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. Siskiyou where it started
    5,623 ha reached on 16 Aug
    0.3 %

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 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)
15 Aug 37.8 °C 19 % 42 km/h 0.4 mm Very high 46
16 Aug 39.6 °C 19 % 40 km/h 0.1 mm Very high 42
17 Aug 34.5 °C 25 % 51 km/h 0.0 mm Very high 42
18 Aug 33.5 °C 29 % 42 km/h 0.0 mm High 38
19 Aug 33.0 °C 32 % 44 km/h 2.1 mm Moderate 19
20 Aug 30.7 °C 41 % 35 km/h 1.3 mm Moderate 16
21 Aug 27.3 °C 54 % 48 km/h 1.9 mm Low 7
22 Aug 24.8 °C 53 % 30 km/h 1.0 mm Low 10
23 Aug 30.2 °C 32 % 33 km/h 0.0 mm High 22
24 Aug after 30.8 °C 33 % 35 km/h 1.4 mm Moderate 18

Before and after, from space

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

Before · 8 Aug 2023
After · 30 Aug 2023

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 18 August 2023 the air beside the fire reached 130 µg/m³ of PM2.5. That day averaged 94: 6.3 times the WHO daily guideline (15).

PM2.5 peak130 µg/m³
Days over the guideline2 days
PM10189 µg/m³
Optical depth1.74
131415161718
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 · 201Every 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 Elliot Fire last?
The official perimeter only gives the start date (15 August 2023). The end comes from the heat detections inside the perimeter: it burned until 23 August 2023 (9 days from 15 August 2023), 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 5,603 hectares (56.0 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire only entered Siskiyou (5,623 ha, 0.3 %).
What was the weather like?
During the fire the temperature reached 39.6 °C, humidity dropped to 19 % and gusts hit 51 km/h. The fire danger index (FWI) reached 46, class Very 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
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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. 201 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 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.