How long did the Goldstone Fire last?

The official perimeter only gives the start date (2 August 2018). The end comes from the heat detections inside the perimeter: it burned until 21 September 2018 (51 days from 2 August 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 3,974 hectares (39.7 km²). Other tallies, such as daily incident reports, may give slightly different figures.

Which counties burned?

The fire entered 2 counties: Beaverhead (3,233 ha, 0.2 %); Lemhi (732 ha, 0.1 %).

What was the weather like?

During the fire the temperature reached 28.6 °C, humidity dropped to 8 % and gusts hit 66 km/h. The fire danger index (FWI) reached 49, 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.

US · United States · 2018-08-02 → 2018-09-21

Goldstone Fire, August 2018 Beaverhead, Lemhi

Out · last detection 21 Sept 2018, 19:51 UTC

The fire started on 2 August 2018 in Beaverhead, United States, and satellites saw it burning for 51 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 3,974 hectares, spread across 2 counties.

It is the 64th largest in Montana since 2016 (of 302 with a page). Number 127 in United States in 2018, of 511.

Compare with…

Suggestions: Big Hollow · 2024 Bear Creek · 2020 Thunder · 2024

Burnt area: 3,974ha; official perimeter (MTBS / NIFC)
Duration: ≈ 51days; 2 Aug 2018 – 21 Sept 2018
Counties hit: 2; counties
Started on: 2 Aug; 2018
Heat detections: 759; in a single hotspot: 605 MW
Danger at start: 39; Very high · FWI index
Average daily power: 768MW; detected power per day, on average

HOTSPOTS BY DAY 2 Aug21 Sept

Play back 21 Sept 2018

How it evolved, day by day

3 Aug 9 Aug 13 Aug 15 Aug 17 Aug 23 Aug 5 Sept 10 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

29°high

66km/h · peak gust

8%lowest humidity

It had gone 16 days without rain (1 mm or more) when it started. Rain came after the fire: 4.0 mm on 23 Sept.

This area had burned before

No earlier perimeters overlap this fire since 2016, when the satellite record begins.

How big is it?

It burned the equivalent of 2.5% of the area of London (40 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

Beaverhead where it started

3,233 ha reached on 3 Aug

0.2 %
Lemhi

732 ha reached on 8 Aug

0.1 %

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)
2 Aug	24.4 °C	11 %	51 km/h	0.3 mm	Very high 39
3 Aug	21.9 °C	9 %	66 km/h	1.1 mm	High 35
4 Aug	20.3 °C	12 %	46 km/h	0.0 mm	High 36
5 Aug	17.3 °C	24 %	28 km/h	0.2 mm	High 29
6 Aug	21.1 °C	17 %	28 km/h	0.0 mm	High 30
7 Aug	22.3 °C	14 %	32 km/h	0.0 mm	High 33
8 Aug	25.6 °C	12 %	34 km/h	0.0 mm	High 36
9 Aug	27.5 °C	10 %	23 km/h	0.0 mm	High 36
10 Aug	28.6 °C	10 %	18 km/h	0.0 mm	High 38
11 Aug	26.3 °C	13 %	55 km/h	0.0 mm	Very high 45
12 Aug	23.9 °C	11 %	54 km/h	0.0 mm	Very high 49
13 Aug	22.8 °C	15 %	40 km/h	0.0 mm	Very high 42
14 Aug	22.3 °C	10 %	37 km/h	0.0 mm	Very high 42
15 Aug	24.4 °C	8 %	34 km/h	0.0 mm	Very high 41
16 Aug	22.8 °C	12 %	31 km/h	0.0 mm	Very high 42
17 Aug	22.0 °C	17 %	46 km/h	0.6 mm	High 33
18 Aug	17.3 °C	27 %	34 km/h	0.5 mm	High 30
19 Aug	20.3 °C	21 %	32 km/h	0.0 mm	High 30
20 Aug	14.3 °C	32 %	34 km/h	12.9 mm	Very low 1
21 Aug	12.6 °C	43 %	26 km/h	0.5 mm	Very low 4
22 Aug	13.4 °C	38 %	49 km/h	1.2 mm	Low 6
23 Aug	19.5 °C	23 %	37 km/h	0.0 mm	Moderate 15
24 Aug	17.6 °C	20 %	60 km/h	0.1 mm	High 27
25 Aug	17.6 °C	19 %	52 km/h	0.2 mm	High 29
26 Aug	11.6 °C	29 %	42 km/h	0.9 mm	Moderate 15
27 Aug	4.7 °C	81 %	33 km/h	8.0 mm	Very low 0
28 Aug	13.6 °C	31 %	30 km/h	0.0 mm	Very low 2
29 Aug	18.8 °C	19 %	39 km/h	0.0 mm	Low 9
30 Aug	18.2 °C	23 %	58 km/h	0.1 mm	Moderate 20
31 Aug	16.3 °C	26 %	38 km/h	0.0 mm	Moderate 18
1 Sept	17.1 °C	23 %	34 km/h	0.0 mm	Moderate 19
2 Sept	18.5 °C	18 %	32 km/h	0.0 mm	High 22
3 Sept	19.5 °C	20 %	36 km/h	0.0 mm	High 23
4 Sept	19.4 °C	23 %	31 km/h	0.0 mm	High 22
5 Sept	21.5 °C	15 %	30 km/h	0.2 mm	High 25
6 Sept	21.3 °C	15 %	45 km/h	0.6 mm	High 24
7 Sept	21.2 °C	19 %	38 km/h	0.0 mm	High 28
8 Sept	20.0 °C	15 %	48 km/h	0.0 mm	High 31
9 Sept	18.9 °C	15 %	40 km/h	0.0 mm	High 30
10 Sept	19.8 °C	14 %	53 km/h	0.0 mm	High 34
11 Sept	16.3 °C	17 %	59 km/h	0.0 mm	High 37
12 Sept	11.2 °C	27 %	44 km/h	1.2 mm	Moderate 12
13 Sept	8.0 °C	43 %	44 km/h	0.5 mm	Moderate 13
14 Sept	12.9 °C	23 %	48 km/h	0.0 mm	Moderate 21
15 Sept	11.9 °C	27 %	50 km/h	2.7 mm	Low 5
16 Sept	15.3 °C	14 %	54 km/h	0.0 mm	Moderate 17
17 Sept	16.3 °C	14 %	37 km/h	0.0 mm	High 23
18 Sept	16.1 °C	14 %	38 km/h	0.0 mm	High 26
19 Sept	12.1 °C	29 %	27 km/h	0.9 mm	Moderate 12
20 Sept	11.1 °C	21 %	45 km/h	0.4 mm	High 22
21 Sept	15.4 °C	22 %	37 km/h	0.0 mm	High 22
22 Sept after	16.8 °C	15 %	52 km/h	0.0 mm	High 31
23 Sept after	9.1 °C	23 %	46 km/h	4.0 mm	Very low 3

Before and after, from space

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

↔

Before · 26 Jul 2018

After · 28 Sept 2018

Before After

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 · 759Every 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 time	Satellite	FRP (MW)	Lat	Lon

Other fires nearby

All fires in United States ›

Frequently asked questions

How long did the Goldstone Fire last?: The official perimeter only gives the start date (2 August 2018). The end comes from the heat detections inside the perimeter: it burned until 21 September 2018 (51 days from 2 August 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 3,974 hectares (39.7 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?: The fire entered 2 counties: Beaverhead (3,233 ha, 0.2 %); Lemhi (732 ha, 0.1 %).
What was the weather like?: During the fire the temperature reached 28.6 °C, humidity dropped to 8 % and gusts hit 66 km/h. The fire danger index (FWI) reached 49, 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

NASA FIRMS ↗
NIFC · Fire maps ↗

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?

Dates or duration Place or towns Burned area Name It was not a wildfire Same fire as another page Something else

What really happened?

Your connection to the fire (optional) Email (optional)

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. 759 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.

Where it burned