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Roosevelt Fire, September 2018 Sublette

Out · last detection 1 Oct 2018, 20:03 UTC

The fire started on 15 September 2018 in Sublette, United States, and satellites saw it burning for 17 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 22,375 hectares, spread across a single county.

It is the 6th largest in Wyoming since 2016 (of 117 with a page). Number 30 in United States in 2018, of 511.

Compare with…

Suggestions: Horse · 2025Cliff Creek · 2016

Burnt area
22,375ha
official perimeter (MTBS / NIFC)
Duration
≈ 17days
15 Sept 2018 – 1 Oct 2018
Counties hit
1
counties
Started on
15 Sept
2018
Heat detections
2,787
in a single hotspot: 1,740 MW
Danger at start
33
High · FWI index
Average daily power
6.6GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 15 Sept1 Oct
1 Oct 2018

How it evolved, day by day

15 Sept 2018 · 20 MW · 1 16 Sept 2018 · 3,311 MW · 43 17 Sept 2018 · 12,540 MW · 206 18 Sept 2018 · 22,860 MW · 205 19 Sept 2018 · 826 MW · 180 20 Sept 2018 · 10,570 MW · 332 21 Sept 2018 · 4,786 MW · 174 22 Sept 2018 · 8,521 MW · 269 23 Sept 2018 · 16,397 MW · 230 24 Sept 2018 · 3,136 MW · 251 25 Sept 2018 · 614 MW · 84 26 Sept 2018 · 4,142 MW · 135 27 Sept 2018 · 12,552 MW · 149 28 Sept 2018 · 10,986 MW · 275 29 Sept 2018 · 754 MW · 171 30 Sept 2018 · 313 MW · 62 1 Oct 2018 · 124 MW · 20
15 Sept 18 Sept 21 Sept 24 Sept 27 Sept 30 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

24°high
58km/h · peak gust
14%lowest humidity

It had gone 6 days without rain (1 mm or more) when it started. Rain came after the fire: 1.0 mm on 2 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 14% of the area of London (224 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. Sublette where it started
    22,467 ha reached on 15 Sept
    1.8 %

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 area2.4 ha
Residents≈ 100

Inside the perimeter there were about 2.4 hectares of built-up land and about 100 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)
15 Sept 23.6 °C 15 % 52 km/h 0.0 mm High 33
16 Sept 22.3 °C 16 % 51 km/h 0.0 mm High 34
17 Sept 21.9 °C 14 % 39 km/h 0.0 mm High 30
18 Sept 22.7 °C 15 % 47 km/h 0.0 mm High 32
19 Sept 20.0 °C 14 % 35 km/h 0.0 mm High 28
20 Sept 14.1 °C 20 % 58 km/h 0.0 mm High 34
21 Sept 18.5 °C 18 % 40 km/h 0.0 mm High 29
22 Sept 22.1 °C 15 % 54 km/h 0.0 mm High 36
23 Sept 16.4 °C 22 % 53 km/h 0.0 mm High 34
24 Sept 13.0 °C 23 % 56 km/h 0.2 mm High 34
25 Sept 13.5 °C 18 % 34 km/h 0.0 mm High 27
26 Sept 15.2 °C 21 % 48 km/h 0.0 mm High 31
27 Sept 17.4 °C 28 % 57 km/h 0.0 mm High 31
28 Sept 19.4 °C 22 % 54 km/h 0.0 mm High 31
29 Sept 20.2 °C 17 % 45 km/h 0.0 mm High 31
30 Sept 13.7 °C 46 % 55 km/h 3.1 mm Very low 5
1 Oct 15.0 °C 29 % 40 km/h 0.0 mm Low 9
2 Oct after 16.2 °C 42 % 54 km/h 1.0 mm Low 10

Before and after, from space

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

Before · 8 Sept 2018
After · 8 Oct 2018

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 · 2,787Every 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 Roosevelt Fire last?
The official perimeter only gives the start date (15 September 2018). The end comes from the heat detections inside the perimeter: it burned until 1 October 2018 (17 days from 15 September 2018), 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 22,375 hectares (223.8 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire only entered Sublette (22,467 ha, 1.8 %).
What was the weather like?
During the fire the temperature reached 23.6 °C, humidity dropped to 14 % and gusts hit 58 km/h. The fire danger index (FWI) reached 36, 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
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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. 2,787 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.