Skip to content
worldfires
US · United States · →

Microwave Fire, July 2017 Big Horn

Out · last detection 21 Jul 2017, 19:56 UTC

The fire started on 20 July 2017 in Big Horn, United States, and satellites saw it burning for 1 day. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 2,413 hectares, spread across a single county.

It is the 96th largest in Montana since 2016 (of 302 with a page). Number 235 in United States in 2017, of 619.

Burnt area
2,413ha
official perimeter (MTBS / NIFC)
Duration
1day
20 Jul 2017 – 20 Jul 2017
Municipalities hit
1
counties
Started on
20 Jul
2017
Heat detections
78
in a single hotspot: 35 MW
Danger at start
43
Very high · FWI index
Energy released
626MW
sum of detected power

Where it burned

HOTSPOTS BY DAY 20 Jul20 Jul

How it evolved, day by day

21

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

The weather it burned in

35°high
30km/h · peak gust
11%lowest humidity

It had gone 21 days without rain (1 mm or more) when it started.

This area had burned before

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

What happened to each town

  1. Big Horn where it started
    2,415 ha reached on 21 Jul
    0.2 %

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)
20 Jul 35.2 °C 20 % 27 km/h 0.6 mm Very high 43
21 Jul after 33.7 °C 11 % 30 km/h 0.0 mm Very high 50
22 Jul after 32.5 °C 13 % 20 km/h 0.0 mm Very high 45
23 Jul after 35.4 °C 14 % 20 km/h 0.0 mm Very high 45
24 Jul after 33.9 °C 20 % 41 km/h 0.0 mm Extreme 55
25 Jul after 25.6 °C 24 % 33 km/h 0.0 mm Very high 43
26 Jul after 31.9 °C 23 % 28 km/h 0.0 mm Very high 41
27 Jul after 33.6 °C 21 % 28 km/h 0.0 mm Very high 39
28 Jul after 34.0 °C 18 % 29 km/h 0.0 mm Very high 44
29 Jul after 31.1 °C 26 % 24 km/h 0.0 mm Very high 38
30 Jul after 35.2 °C 13 % 18 km/h 0.0 mm Very high 44
31 Jul after 35.9 °C 10 % 34 km/h 0.0 mm Extreme 56

Before and after, from space

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

Before · 13 Jul 2017
After · 27 Jul 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 · 78Every 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 Microwave fire last?
It burned between 20 July 2017 and 20 July 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 2,413 hectares (24.1 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire only entered Big Horn (2,415 ha, 0.2 %).
What was the weather like?
During the fire the temperature reached 35.2 °C, humidity dropped to 11 % and gusts hit 30 km/h. The fire danger index (FWI) reached 50, 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

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.

Report an error
What do you think is wrong?

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.

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.