How long did the Lava Mountain Fire last?

The official perimeter only gives the start date (11 July 2016). The end comes from the heat detections inside the perimeter: it burned until 6 August 2016 (27 days from 11 July 2016), 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 5,927 hectares (59.3 km²). Other tallies, such as daily incident reports, may give slightly different figures.

Which counties burned?

The fire only entered Fremont (5,968 ha, 0.2 %).

What was the weather like?

During the fire the temperature reached 25.5 °C, humidity dropped to 9 % and gusts hit 76 km/h. The fire danger index (FWI) reached 47, 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 · 2016-07-11 → 2016-08-06

Lava Mountain Fire, July 2016 Fremont

Out · last detection 6 Aug 2016, 20:41 UTC

The fire started on 11 July 2016 in Fremont, United States, and satellites saw it burning for 27 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 5,927 hectares, spread across a single county.

It is the 24th largest in Wyoming since 2016 (of 117 with a page). Number 61 in United States in 2016, of 475.

Compare with…

Suggestions: Dollar Lake · 2025

Burnt area: 5,927ha; official perimeter (MTBS / NIFC)
Duration: ≈ 27days; 11 Jul 2016 – 6 Aug 2016
Counties hit: 1; counties
Started on: 11 Jul; 2016
Heat detections: 1,291; in a single hotspot: 591 MW
Danger at start: 4; Very low · FWI index
Average daily power: 2.9GW; detected power per day, on average

HOTSPOTS BY DAY 11 Jul6 Aug

Play back 6 Aug 2016

How it evolved, day by day

17 Jul 20 Jul 23 Jul 25 Jul 26 Jul 29 Jul 1 Aug 5 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

26°high

76km/h · peak gust

9%lowest humidity

It had gone 0 days without rain (1 mm or more) when it started. Rain came after the fire: 8.2 mm on 7 Aug.

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 3.7% of the area of London (59 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

Fremont where it started

5,968 ha reached on 17 Jul

0.2 %

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 2015

Built-up area0.46 ha

Residents< 20

Inside the perimeter there were about 0.46 hectares of built-up land and almost nobody lived there (GHSL 2015, 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)
11 Jul	10.7 °C	47 %	63 km/h	0.8 mm	Very low 4
12 Jul	17.4 °C	28 %	66 km/h	0.7 mm	Low 9
13 Jul	17.8 °C	26 %	53 km/h	0.0 mm	Moderate 14
14 Jul	21.4 °C	19 %	53 km/h	0.0 mm	Moderate 20
15 Jul	21.3 °C	25 %	54 km/h	0.0 mm	Moderate 21
16 Jul	19.9 °C	22 %	76 km/h	0.1 mm	High 27
17 Jul	21.8 °C	23 %	52 km/h	1.3 mm	Moderate 15
18 Jul	22.8 °C	23 %	56 km/h	0.0 mm	High 22
19 Jul	23.1 °C	27 %	50 km/h	1.1 mm	Moderate 15
20 Jul	24.3 °C	21 %	62 km/h	0.1 mm	High 26
21 Jul	24.9 °C	20 %	46 km/h	0.0 mm	High 26
22 Jul	23.3 °C	25 %	62 km/h	0.0 mm	High 31
23 Jul	21.6 °C	19 %	52 km/h	0.0 mm	High 28
24 Jul	23.6 °C	16 %	40 km/h	0.0 mm	High 28
25 Jul	24.8 °C	14 %	50 km/h	0.2 mm	High 35
26 Jul	24.8 °C	14 %	54 km/h	0.0 mm	High 34
27 Jul	25.5 °C	17 %	48 km/h	0.0 mm	High 36
28 Jul	24.2 °C	16 %	53 km/h	0.0 mm	Very high 38
29 Jul	25.2 °C	17 %	49 km/h	0.0 mm	High 37
30 Jul	23.7 °C	22 %	60 km/h	0.8 mm	High 30
31 Jul	23.6 °C	24 %	58 km/h	0.0 mm	High 31
1 Aug	24.5 °C	16 %	55 km/h	0.0 mm	High 36
2 Aug	24.6 °C	17 %	59 km/h	0.0 mm	Very high 39
3 Aug	22.3 °C	10 %	72 km/h	0.0 mm	Very high 47
4 Aug	23.5 °C	9 %	29 km/h	0.0 mm	High 34
5 Aug	22.6 °C	20 %	38 km/h	0.0 mm	High 36
6 Aug	20.4 °C	28 %	44 km/h	0.9 mm	High 22
7 Aug after	20.9 °C	37 %	58 km/h	8.2 mm	Very low 4

Before and after, from space

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

↔

Before · 4 Jul 2016

After · 13 Aug 2016

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 · 1,291Every 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

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Frequently asked questions

How long did the Lava Mountain Fire last?: The official perimeter only gives the start date (11 July 2016). The end comes from the heat detections inside the perimeter: it burned until 6 August 2016 (27 days from 11 July 2016), 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 5,927 hectares (59.3 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?: The fire only entered Fremont (5,968 ha, 0.2 %).
What was the weather like?: During the fire the temperature reached 25.5 °C, humidity dropped to 9 % and gusts hit 76 km/h. The fire danger index (FWI) reached 47, 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.

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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.

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What really happened?

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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. 1,291 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 2015, 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