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River Fire, July 2021 Madera, Mariposa

Out · last detection 12 Jul 2021, 21:10 UTC

The fire started on 11 July 2021 in Madera, United States, and satellites saw it burning for 1 day. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 4,126 hectares, spread across 2 counties.

It is the 144th largest in California since 2016 (of 442 with a page). Number 103 in United States in 2021, of 385.

Burnt area
4,126ha
official perimeter (MTBS / NIFC)
Duration
1day
11 Jul 2021 – 11 Jul 2021
Municipalities hit
2
counties
Started on
11 Jul
2021
Heat detections
301
in a single hotspot: 137 MW
Danger at start
60
Extreme · FWI index
Energy released
4.3GW
sum of detected power

Where it burned

12 Jul 2021
HOTSPOTS BY DAY 11 Jul11 Jul

How it evolved, day by day

1112

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

The weather it burned in

44°high
42km/h · peak gust
12%lowest humidity

It had gone more than two months 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. Madera where it started
    3,587 ha reached on 12 Jul
    0.6 %
  2. Mariposa
    529 ha reached on 11 Jul
    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)
11 Jul 43.8 °C 13 % 42 km/h 0.0 mm Extreme 60
12 Jul after 41.8 °C 12 % 36 km/h 0.0 mm Extreme 55
13 Jul after 39.2 °C 16 % 35 km/h 0.0 mm Extreme 55
14 Jul after 37.1 °C 21 % 34 km/h 0.0 mm Very high 48
15 Jul after 36.4 °C 16 % 34 km/h 0.0 mm Very high 47
16 Jul after 36.2 °C 18 % 33 km/h 0.0 mm Very high 47
17 Jul after 38.0 °C 18 % 32 km/h 0.0 mm Very high 46
18 Jul after 36.9 °C 20 % 35 km/h 0.0 mm Very high 49
19 Jul after 39.1 °C 19 % 31 km/h 0.0 mm Very high 47
20 Jul after 38.2 °C 19 % 37 km/h 0.0 mm Very high 50
21 Jul after 37.8 °C 11 % 36 km/h 0.0 mm Extreme 50
22 Jul after 37.9 °C 13 % 35 km/h 0.0 mm Extreme 51
23 Jul after 38.3 °C 13 % 32 km/h 0.0 mm Very high 50

Before and after, from space

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

Before · 4 Jul 2021
After · 18 Jul 2021

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 · 301Every 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 11 July 2021 and 11 July 2021: 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 4,126 hectares (41.3 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire entered 2 counties: Madera (3,587 ha, 0.6 %); Mariposa (529 ha, 0.1 %).
What was the weather like?
During the fire the temperature reached 43.8 °C, humidity dropped to 12 % and gusts hit 42 km/h. The fire danger index (FWI) reached 60, 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.