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River Fire, September 2019 Maricopa

Out · last detection 4 Sept 2019, 21:03 UTC

The fire started on 3 September 2019 in Maricopa, United States, and satellites saw it burning for 1 day. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 3,153 hectares, spread across a single county.

It is the 101th largest in Arizona since 2016 (of 380 with a page). Number 90 in United States in 2019, of 367.

The power measured by the satellite is low (29.3 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Burnt area
3,153ha
official perimeter (MTBS / NIFC)
Duration
1day
3 Sept 2019 – 3 Sept 2019
Municipalities hit
1
counties
Started on
3 Sept
2019
Heat detections
73
in a single hotspot: 29 MW
Danger at start
52
Extreme · FWI index
Energy released
108MW
sum of detected power

Where it burned

HOTSPOTS BY DAY 3 Sept3 Sept

How it evolved, day by day

4

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

The weather it burned in

37°high
45km/h · peak gust
13%lowest humidity

It had gone one day without rain (1 mm or more) when it started. Rain came after the fire: 1.9 mm on 10 Sept.

This area had burned before

30% of the perimeter overlaps earlier fires recorded since 2016: 945 ha in 2018.

What happened to each town

  1. Maricopa where it started
    3,186 ha reached on 4 Sept
    0.1 %

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)
3 Sept 37.4 °C 13 % 30 km/h 0.0 mm Extreme 52
4 Sept after 36.8 °C 16 % 37 km/h 0.2 mm Extreme 52
5 Sept after 36.3 °C 14 % 34 km/h 0.0 mm Extreme 50
6 Sept after 36.0 °C 15 % 37 km/h 0.0 mm Extreme 51
7 Sept after 35.0 °C 16 % 40 km/h 1.9 mm High 37
8 Sept after 30.7 °C 27 % 45 km/h 2.0 mm High 26
9 Sept after 29.8 °C 27 % 39 km/h 0.0 mm High 33
10 Sept after 29.6 °C 20 % 44 km/h 1.9 mm High 26

Before and after, from space

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

Before · 27 Aug 2019
After · 10 Sept 2019

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 · 73Every 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 River fire last?
It burned between 3 September 2019 and 3 September 2019: 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 3,153 hectares (31.5 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire only entered Maricopa (3,186 ha, 0.1 %).
What was the weather like?
During the fire the temperature reached 37.4 °C, humidity dropped to 13 % and gusts hit 45 km/h. The fire danger index (FWI) reached 52, class Extreme.
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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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.