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Empire Fire, August 2017 Mariposa

Out · last detection 2 Aug 2017, 09:49 UTC

The fire started on 1 August 2017 in Mariposa, United States, and satellites saw it burning for 1 day. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 3,923 hectares, spread across a single county.

It is the 147th largest in California since 2016 (of 442 with a page). Number 168 in United States in 2017, of 619.

Burnt area
3,923ha
official perimeter (MTBS / NIFC)
Duration
1day
1 Aug 2017 – 1 Aug 2017
Municipalities hit
1
counties
Started on
1 Aug
2017
Heat detections
1,904
in a single hotspot: 288 MW
Danger at start
36
High · FWI index
Energy released
185MW
sum of detected power

Where it burned

HOTSPOTS BY DAY 1 Aug1 Aug

How it evolved, day by day

2

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

The weather it burned in

30°high
71km/h · peak gust
12%lowest humidity

It had gone 6 days without rain (1 mm or more) when it started. Rain came after the fire: 3.6 mm on 4 Nov.

This area had burned before

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

What happened to each town

  1. Mariposa where it started
    3,928 ha reached on 2 Aug
    1.0 %

Burnt area inside each county, from crossing the official perimeter with administrative boundaries. The distance is from the town centre to the nearest fire: staying a kilometre away does not mean it reached the houses.

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)
1 Aug 29.9 °C 14 % 35 km/h 0.0 mm High 36
2 Aug after 27.3 °C 22 % 38 km/h 1.9 mm Moderate 16
3 Aug after 25.6 °C 21 % 31 km/h 1.7 mm Moderate 14
4 Aug after 22.3 °C 32 % 38 km/h 2.3 mm Low 8
5 Aug after 20.7 °C 44 % 35 km/h 8.1 mm Very low 1
6 Aug after 21.8 °C 38 % 42 km/h 0.0 mm Low 6
7 Aug after 22.5 °C 33 % 50 km/h 0.3 mm Moderate 15
8 Aug after 23.3 °C 30 % 41 km/h 0.1 mm Moderate 19
9 Aug after 23.0 °C 29 % 41 km/h 0.0 mm Moderate 21
10 Aug after 24.8 °C 23 % 46 km/h 0.0 mm High 26
11 Aug after 24.6 °C 22 % 43 km/h 0.0 mm High 27
12 Aug after 24.6 °C 16 % 44 km/h 0.0 mm High 31
13 Aug after 24.0 °C 18 % 48 km/h 0.0 mm High 32
14 Aug after 21.2 °C 25 % 54 km/h 0.0 mm High 32
15 Aug after 21.0 °C 37 % 35 km/h 0.2 mm High 23
16 Aug after 23.4 °C 35 % 34 km/h 0.9 mm Moderate 15
17 Aug after 24.2 °C 28 % 32 km/h 0.6 mm Moderate 20
18 Aug after 24.5 °C 21 % 39 km/h 0.9 mm Moderate 21
19 Aug after 23.3 °C 29 % 35 km/h 2.4 mm Low 7
20 Aug after 22.2 °C 33 % 34 km/h 2.4 mm Very low 5
21 Aug after 19.2 °C 38 % 33 km/h 3.2 mm Very low 3
22 Aug after 20.3 °C 38 % 33 km/h 3.0 mm Very low 3
23 Aug after 22.8 °C 36 % 34 km/h 1.3 mm Very low 5
24 Aug after 23.4 °C 30 % 39 km/h 0.1 mm Moderate 14
25 Aug after 24.1 °C 31 % 42 km/h 0.5 mm Moderate 18
26 Aug after 25.3 °C 28 % 29 km/h 0.0 mm Moderate 21
27 Aug after 26.3 °C 26 % 40 km/h 0.0 mm High 24
28 Aug after 27.9 °C 17 % 52 km/h 0.0 mm High 31
29 Aug after 27.8 °C 21 % 44 km/h 0.0 mm High 33
30 Aug after 25.6 °C 25 % 44 km/h 3.8 mm Low 7
31 Aug after 24.9 °C 26 % 48 km/h 0.0 mm Moderate 19
1 Sept after 27.1 °C 21 % 36 km/h 0.0 mm High 24
2 Sept after 28.1 °C 22 % 30 km/h 0.8 mm High 23
3 Sept after 27.1 °C 18 % 36 km/h 0.0 mm High 27
4 Sept after 24.7 °C 26 % 48 km/h 0.3 mm High 29
5 Sept after 23.8 °C 26 % 37 km/h 2.7 mm Low 6
6 Sept after 22.6 °C 47 % 49 km/h 3.9 mm Very low 3
7 Sept after 20.2 °C 38 % 48 km/h 0.1 mm Low 8
8 Sept after 18.8 °C 32 % 49 km/h 0.6 mm Moderate 14
9 Sept after 18.8 °C 37 % 28 km/h 1.5 mm Low 5
10 Sept after 22.1 °C 28 % 36 km/h 0.2 mm Moderate 14
11 Sept after 24.0 °C 31 % 35 km/h 1.6 mm Low 9
12 Sept after 20.7 °C 49 % 32 km/h 3.2 mm Very low 3
13 Sept after 19.0 °C 38 % 30 km/h 0.6 mm Low 6
14 Sept after 16.2 °C 50 % 48 km/h 1.0 mm Low 6
15 Sept after 17.5 °C 34 % 36 km/h 0.0 mm Low 11
16 Sept after 17.4 °C 39 % 46 km/h 0.0 mm Moderate 14
17 Sept after 18.8 °C 32 % 43 km/h 0.0 mm Moderate 17
18 Sept after 17.5 °C 22 % 64 km/h 0.0 mm High 24
19 Sept after 16.5 °C 31 % 46 km/h 0.0 mm Moderate 20
20 Sept after 15.5 °C 41 % 66 km/h 1.9 mm Low 7
21 Sept after 7.4 °C 70 % 64 km/h 24.4 mm Very low 0
22 Sept after 6.4 °C 42 % 30 km/h 0.0 mm Very low 0
23 Sept after 9.2 °C 35 % 30 km/h 0.0 mm Very low 2
24 Sept after 11.9 °C 35 % 30 km/h 0.0 mm Very low 4
25 Sept after 13.8 °C 38 % 33 km/h 0.0 mm Low 7
26 Sept after 14.9 °C 36 % 39 km/h 0.0 mm Low 10
27 Sept after 18.0 °C 31 % 39 km/h 0.0 mm Moderate 12
28 Sept after 18.2 °C 34 % 35 km/h 0.0 mm Moderate 12
29 Sept after 16.7 °C 28 % 44 km/h 0.0 mm Moderate 14
30 Sept after 16.7 °C 35 % 40 km/h 0.0 mm Moderate 14
1 Oct after 15.6 °C 22 % 54 km/h 0.0 mm Moderate 18
2 Oct after 11.9 °C 30 % 49 km/h 0.0 mm Moderate 17
3 Oct after 8.5 °C 29 % 57 km/h 1.6 mm Low 6
4 Oct after 14.1 °C 19 % 36 km/h 0.0 mm Low 10
5 Oct after 15.4 °C 19 % 37 km/h 0.0 mm Moderate 15
6 Oct after 20.9 °C 20 % 30 km/h 0.0 mm Moderate 20
7 Oct after 19.6 °C 19 % 42 km/h 0.0 mm Moderate 21
8 Oct after 17.5 °C 21 % 46 km/h 0.0 mm High 22
9 Oct after 16.0 °C 18 % 49 km/h 0.0 mm High 23
10 Oct after 15.3 °C 17 % 47 km/h 0.0 mm High 23
11 Oct after 13.0 °C 21 % 60 km/h 0.0 mm High 25
12 Oct after 12.8 °C 16 % 40 km/h 0.0 mm High 22
13 Oct after 13.5 °C 16 % 45 km/h 0.0 mm High 23
14 Oct after 18.6 °C 17 % 34 km/h 0.0 mm High 22
15 Oct after 19.2 °C 13 % 32 km/h 0.0 mm High 24
16 Oct after 20.3 °C 12 % 26 km/h 0.0 mm High 25
17 Oct after 16.9 °C 17 % 46 km/h 0.0 mm High 29
18 Oct after 18.9 °C 19 % 32 km/h 0.0 mm High 26
19 Oct after 14.9 °C 24 % 51 km/h 0.0 mm High 28
20 Oct after 6.7 °C 49 % 71 km/h 11.7 mm Very low 0
21 Oct after 12.5 °C 25 % 27 km/h 0.0 mm Very low 2
22 Oct after 18.9 °C 13 % 27 km/h 0.0 mm Low 9
23 Oct after 21.8 °C 27 % 37 km/h 0.0 mm Moderate 16
24 Oct after 22.1 °C 25 % 41 km/h 0.0 mm Moderate 19
25 Oct after 21.0 °C 26 % 28 km/h 0.0 mm Moderate 17
26 Oct after 20.9 °C 22 % 24 km/h 0.0 mm Moderate 17
27 Oct after 21.0 °C 24 % 23 km/h 0.0 mm Moderate 18
28 Oct after 20.5 °C 22 % 25 km/h 0.0 mm Moderate 19
29 Oct after 18.5 °C 25 % 31 km/h 0.0 mm Moderate 20
30 Oct after 15.5 °C 24 % 45 km/h 0.0 mm High 22
31 Oct after 13.1 °C 39 % 31 km/h 0.0 mm Moderate 17
1 Nov after 14.5 °C 34 % 30 km/h 0.0 mm Moderate 17
2 Nov after 9.4 °C 46 % 35 km/h 0.0 mm Moderate 15
3 Nov after 6.4 °C 55 % 46 km/h 1.5 mm Very low 5
4 Nov after 5.5 °C 52 % 50 km/h 3.6 mm Very low 1

Before and after, from space

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

Before · 25 Jul 2017
After · 8 Aug 2017

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 · 1,904Every 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 Empire fire last?
It burned between 1 August 2017 and 1 August 2017: 1 day, according to the start date recorded by United States agencies (MTBS / NIFC) and the heat detections seen by satellite.
How much area did it burn?
The official perimeter published by United States agencies (MTBS / NIFC) is 3,923 hectares (39.2 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire only entered Mariposa (3,928 ha, 1.0 %).
What was the weather like?
During the fire the temperature reached 29.9 °C, humidity dropped to 12 % and gusts hit 71 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

Satellite cross-check

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.

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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.