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Crescent Mountain Fire, July 2018 Okanogan, Chelan

Out · last detection 28 Sept 2018, 09:34 UTC

The fire started on 29 July 2018 in Okanogan, United States, and satellites saw it burning for 62 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 21,555 hectares, spread across 2 counties.

It is the 21th largest in Washington since 2016 (of 285 with a page). Number 34 in United States in 2018, of 511.

Compare with…

Suggestions: Cedar Creek · 2021Sisi · 2026Uno Peak · 2017Pomas · 2025

Burnt area
21,555ha
official perimeter (MTBS / NIFC)
Duration
≈ 62days
29 Jul 2018 – 28 Sept 2018
Counties hit
2
counties
Started on
29 Jul
2018
Heat detections
6,494
in a single hotspot: 311 MW
Danger at start
27
High · FWI index
Average daily power
1.6GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 29 Jul28 Sept
28 Sept 2018

How it evolved, day by day

30 Jul 2018 · 34 MW · 2 31 Jul 2018 · 11 MW · 3 1 Aug 2018 · 816 MW · 32 2 Aug 2018 · 2,105 MW · 259 3 Aug 2018 · 1,329 MW · 142 4 Aug 2018 · 1,013 MW · 126 5 Aug 2018 · 322 MW · 61 6 Aug 2018 · 1,750 MW · 82 7 Aug 2018 · 3,885 MW · 300 8 Aug 2018 · 2,561 MW · 367 9 Aug 2018 · 1,606 MW · 270 10 Aug 2018 · 2,941 MW · 175 11 Aug 2018 · 2,633 MW · 183 12 Aug 2018 · 227 MW · 87 13 Aug 2018 · 213 MW · 72 14 Aug 2018 · 210 MW · 51 15 Aug 2018 · 1,694 MW · 111 16 Aug 2018 · 2,611 MW · 164 17 Aug 2018 · 2,211 MW · 271 18 Aug 2018 · 5,659 MW · 381 19 Aug 2018 · 561 MW · 138 20 Aug 2018 · 10,005 MW · 369 21 Aug 2018 · 6,139 MW · 373 22 Aug 2018 · 1,826 MW · 329 23 Aug 2018 · 10,946 MW · 537 24 Aug 2018 · 4,543 MW · 296 25 Aug 2018 · 390 MW · 133 26 Aug 2018 · 10 MW · 10 27 Aug 2018 · 167 MW · 29 28 Aug 2018 · 281 MW · 39 29 Aug 2018 · 195 MW · 47 30 Aug 2018 · 1,360 MW · 37 31 Aug 2018 · 1,204 MW · 127 1 Sept 2018 · 928 MW · 103 2 Sept 2018 · 2,296 MW · 148 3 Sept 2018 · 1,682 MW · 125 4 Sept 2018 · 385 MW · 90 5 Sept 2018 · 732 MW · 106 6 Sept 2018 · 1,770 MW · 96 7 Sept 2018 · 2,423 MW · 172 8 Sept 2018 · 24 MW · 14 9 Sept 2018 · 22 MW · 3 10 Sept 2018 · 78 MW · 15 11 Sept 2018 · 7 MW · 5 13 Sept 2018 · 6 MW · 3 14 Sept 2018 · 2 MW · 2 15 Sept 2018 · 4 MW · 4 16 Sept 2018 · 2 MW · 1 19 Sept 2018 · 3 MW · 1 27 Sept 2018 · 2 MW · 2 28 Sept 2018 · 2 MW · 1
30 Jul 7 Aug 15 Aug 23 Aug 31 Aug 8 Sept 19 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

30°high
72km/h · peak gust
15%lowest humidity

It had gone 2 days without rain (1 mm or more) when it started. Rain came after the fire: 2.2 mm on 29 Sept.

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 (216 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. Okanogan where it started
    21,352 ha reached on 30 Jul
    1.6 %
  2. Chelan
    113 ha reached on 20 Aug
    0.0 %

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.

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)
29 Jul 26.7 °C 15 % 28 km/h 0.0 mm High 27
30 Jul 27.4 °C 17 % 32 km/h 0.0 mm High 27
31 Jul 25.2 °C 25 % 49 km/h 0.7 mm High 22
1 Aug 21.3 °C 29 % 54 km/h 0.0 mm High 25
2 Aug 18.8 °C 32 % 51 km/h 0.0 mm High 25
3 Aug 15.6 °C 41 % 50 km/h 0.0 mm Moderate 21
4 Aug 18.2 °C 36 % 35 km/h 3.3 mm Very low 4
5 Aug 21.8 °C 23 % 24 km/h 0.0 mm Low 11
6 Aug 23.6 °C 18 % 52 km/h 0.0 mm High 24
7 Aug 26.0 °C 17 % 35 km/h 0.0 mm High 27
8 Aug 28.3 °C 18 % 34 km/h 0.0 mm High 27
9 Aug 29.8 °C 19 % 39 km/h 0.2 mm High 29
10 Aug 28.3 °C 24 % 38 km/h 0.5 mm High 30
11 Aug 18.1 °C 39 % 54 km/h 1.6 mm Low 10
12 Aug 16.7 °C 39 % 46 km/h 0.0 mm Moderate 14
13 Aug 19.9 °C 31 % 28 km/h 0.0 mm Moderate 16
14 Aug 23.0 °C 28 % 26 km/h 0.0 mm Moderate 19
15 Aug 24.0 °C 18 % 33 km/h 0.0 mm High 26
16 Aug 23.2 °C 21 % 40 km/h 0.0 mm High 28
17 Aug 21.5 °C 25 % 41 km/h 0.0 mm High 28
18 Aug 21.7 °C 27 % 36 km/h 0.0 mm High 27
19 Aug 18.6 °C 36 % 24 km/h 0.0 mm High 23
20 Aug 20.9 °C 29 % 52 km/h 0.0 mm High 27
21 Aug 22.6 °C 23 % 27 km/h 0.0 mm High 24
22 Aug 23.4 °C 27 % 42 km/h 0.0 mm High 27
23 Aug 17.7 °C 37 % 53 km/h 0.0 mm High 25
24 Aug 14.6 °C 35 % 56 km/h 0.0 mm High 23
25 Aug 11.1 °C 53 % 38 km/h 0.0 mm Moderate 17
26 Aug 9.5 °C 62 % 45 km/h 2.1 mm Very low 5
27 Aug 16.9 °C 26 % 47 km/h 0.0 mm Low 9
28 Aug 20.2 °C 29 % 29 km/h 0.0 mm Moderate 16
29 Aug 16.8 °C 36 % 72 km/h 0.0 mm High 22
30 Aug 14.8 °C 35 % 59 km/h 0.0 mm Moderate 20
31 Aug 15.5 °C 36 % 52 km/h 0.0 mm Moderate 19
1 Sept 16.2 °C 27 % 56 km/h 0.0 mm Moderate 21
2 Sept 18.1 °C 27 % 51 km/h 0.0 mm High 24
3 Sept 16.5 °C 25 % 47 km/h 0.0 mm High 23
4 Sept 16.1 °C 30 % 28 km/h 0.0 mm Moderate 21
5 Sept 18.9 °C 22 % 27 km/h 0.0 mm High 24
6 Sept 21.5 °C 22 % 30 km/h 0.0 mm High 26
7 Sept 19.6 °C 31 % 57 km/h 1.3 mm Moderate 13
8 Sept 13.8 °C 39 % 38 km/h 0.0 mm Moderate 15
9 Sept 15.5 °C 38 % 50 km/h 0.8 mm Moderate 14
10 Sept 11.7 °C 42 % 48 km/h 1.2 mm Low 9
11 Sept 10.3 °C 42 % 34 km/h 2.5 mm Very low 4
12 Sept 10.9 °C 41 % 27 km/h 4.5 mm Very low 1
13 Sept 9.9 °C 45 % 32 km/h 2.1 mm Very low 1
14 Sept 9.6 °C 60 % 31 km/h 3.9 mm Very low 0
15 Sept 8.4 °C 49 % 32 km/h 2.1 mm Very low 0
16 Sept 7.0 °C 68 % 47 km/h 6.6 mm Very low 0
17 Sept 12.1 °C 29 % 31 km/h 0.0 mm Very low 1
18 Sept 14.0 °C 26 % 22 km/h 0.0 mm Very low 2
19 Sept 12.5 °C 44 % 34 km/h 2.8 mm Very low 1
20 Sept 10.3 °C 40 % 41 km/h 0.1 mm Very low 2
21 Sept 13.1 °C 46 % 61 km/h 2.2 mm Very low 1
22 Sept 9.6 °C 67 % 53 km/h 7.8 mm Very low 0
23 Sept 8.7 °C 47 % 46 km/h 0.0 mm Very low 0
24 Sept 13.1 °C 34 % 36 km/h 0.0 mm Very low 1
25 Sept 14.5 °C 34 % 18 km/h 0.0 mm Very low 2
26 Sept 17.5 °C 30 % 23 km/h 0.0 mm Low 5
27 Sept 17.8 °C 36 % 31 km/h 0.0 mm Low 7
28 Sept 15.2 °C 40 % 27 km/h 0.0 mm Low 8
29 Sept after 7.4 °C 51 % 30 km/h 2.2 mm Very low 1

Before and after, from space

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

Before · 22 Jul 2018
After · 5 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 · 6,494Every 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 Crescent Mountain Fire last?
The official perimeter only gives the start date (29 July 2018). The end comes from the heat detections inside the perimeter: it burned until 28 September 2018 (62 days from 29 July 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 21,555 hectares (215.6 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire entered 2 counties: Okanogan (21,352 ha, 1.6 %); Chelan (113 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 29.8 °C, humidity dropped to 15 % and gusts hit 72 km/h. The fire danger index (FWI) reached 30, 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.

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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. 6,494 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.

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.