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Aspen Acres Fire, June 2026 Custer, Pueblo, Huerfano

Out · last detection 16 Jul 2026, 19:47 UTC

The fire started on 29 June 2026 in Pueblo, United States, and satellites saw it burning for 18 days. United States agencies (MTBS / NIFC) mapped an official burnt perimeter of 41,279 hectares, spread across 3 counties.

We are reviewing this page: some of its data look inconsistent (the place, the dates or the area), so treat them with caution.

Compare with…

Suggestions: Skiles 429 · 2022Chateau · 2018Junkins · 2016Beulah Hill · 2016

Burnt area
41,279ha
official perimeter (MTBS / NIFC)
Duration
≈ 18days
29 Jun 2026 – 16 Jul 2026
Counties hit
3
counties
Started on
29 Jun
2026
Heat detections
2,864
in a single hotspot: 679 MW
Danger at start
67
Extreme · FWI index
Average daily power
6.9GW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 29 Jun16 Jul
16 Jul 2026

How it evolved, day by day

29 Jun 2026 · 29,814 MW · 198 30 Jun 2026 · 3,034 MW · 343 1 Jul 2026 · 28,048 MW · 561 2 Jul 2026 · 14,939 MW · 324 3 Jul 2026 · 7,395 MW · 538 4 Jul 2026 · 2,861 MW · 356 5 Jul 2026 · 2,424 MW · 111 6 Jul 2026 · 5,985 MW · 210 10 Jul 2026 · 0 MW · 0 11 Jul 2026 · 87 MW · 7 12 Jul 2026 · 522 MW · 23 13 Jul 2026 · 798 MW · 53 14 Jul 2026 · 487 MW · 58 15 Jul 2026 · 244 MW · 60 16 Jul 2026 · 47 MW · 22
29 Jun 2 Jul 5 Jul 11 Jul 14 Jul

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

The weather it burned in

31°high
70km/h · peak gust
3%lowest humidity

It had gone 2 days without rain (1 mm or more) when it started. Rain came after the fire: 4.6 mm on 22 Jul.

This area had burned before

2% of the perimeter overlaps earlier fires recorded since 2016: 1,028 ha in 2016.

How big is it?

10 km
It burned the equivalent of 26% of the area of London (413 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. Custer
    42,627 ha reached on 29 Jun
    22 %
  2. Pueblo where it started
    40,776 ha reached on 29 Jun
    6.5 %
  3. Huerfano
    49 ha
    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.

People and buildings inside the perimeter

GHSL 2025
Built-up area58 ha
Residents≈ 1,300

Inside the perimeter there were about 58 hectares of built-up land and about 1,300 residents (GHSL 2025, satellite-based estimate).

This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned. The GHSL 2025 epoch is a projection made from 2020 and earlier data.

Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu

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)

Started with Extreme FWI: 36 % of the area in United States Strong wind: 27 % of the area in United States Very dry air: 40 % of the area in United States

Day High Min. humidity Peak gust Rain Danger (FWI)
29 Jun 28.7 °C 4 % 70 km/h 0.0 mm Extreme 67
30 Jun 28.2 °C 14 % 52 km/h 0.2 mm Very high 48
1 Jul 29.3 °C 7 % 48 km/h 0.0 mm Very high 47
2 Jul 30.6 °C 3 % 39 km/h 0.0 mm Very high 40
3 Jul 30.0 °C 7 % 32 km/h 0.0 mm Very high 43
4 Jul 27.1 °C 21 % 36 km/h 0.8 mm Very high 38
5 Jul 29.4 °C 17 % 38 km/h 0.0 mm High 32
6 Jul 30.1 °C 13 % 28 km/h 0.0 mm High 37
7 Jul 31.0 °C 17 % 37 km/h 1.1 mm Very high 38
8 Jul 30.8 °C 15 % 43 km/h 0.3 mm Very high 42
9 Jul 30.5 °C 14 % 27 km/h 0.6 mm Very high 38
10 Jul 29.6 °C 24 % 51 km/h 1.2 mm High 35
11 Jul 30.2 °C 22 % 63 km/h 0.6 mm High 25
12 Jul 28.9 °C 18 % 41 km/h 0.0 mm Very high 42
13 Jul 30.7 °C 19 % 37 km/h 0.1 mm Very high 40
14 Jul 29.1 °C 20 % 44 km/h 0.0 mm Very high 43
15 Jul 28.5 °C 24 % 41 km/h 0.3 mm Very high 39
16 Jul 27.9 °C 24 % 40 km/h 0.4 mm Very high 42
17 Jul after 27.0 °C 25 % 45 km/h 0.1 mm Very high 45
18 Jul after 28.3 °C 23 % 36 km/h 0.1 mm Very high 38
19 Jul after 30.6 °C 20 % 41 km/h 0.0 mm Very high 41
20 Jul after 32.7 °C 12 % 47 km/h 0.0 mm Extreme 53
21 Jul after 30.6 °C 19 % 54 km/h 0.0 mm Extreme 59
22 Jul after 30.2 °C 26 % 29 km/h 4.6 mm High 37

Its twins: fires that started in the same weather

It started with an FWI of 67.3, a minimum humidity of 4% and 2 days without rain. Fires in the area that started in weather like this since 2016: 19.

FWI at the start 67.3
Minimum humidity 4 %
Days without rain 2
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Skiles 429 Fire, April 2022
511 ha 1 day FWI 64.5 Min. humidity 5 % 223 km away, in 2022

First rain (1 mm or more) after it ended: 2.1 mm on 1 May.

See its page Compare with this fire

What happened to them

4 days
median duration
721 ha
median area
37 %
went past 1,000 ha
2.7 mm
rain at the end (median; 18 of 19 had it)

It was 57.2 times larger than the median of its twins and lasted 18 days, against 4 days.

Only 1 of its 19 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 1 of 19, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 2.7 mm.

This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it

How it ended

4.6 mmfirst rain
22 Jul6 days after it ended
70km/h · max. gust

It was considered over on 16 Jul, and on 22 Jul 4.6 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 18 of 19, with a median of 2.7 mm.

Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

How a twin is chosen

  • Same area: fires that have already ended, less than 250 km from this one, since 2016.
  • Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
  • Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
  • Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
  • They are sorted by similarity, and the outlines of the first five are drawn.

How we calculate it

Before and after, from space

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

Before · 22 Jun 2026
After · 23 Jul 2026

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

The smoke

CAMS · Copernicus

On 4 July 2026 the air beside the fire reached 298 µg/m³ of PM2.5. That day averaged 143: 9.5 times the WHO daily guideline (15).

PM2.5 peak298 µg/m³
Days over the guideline9 days
PM10306 µg/m³
Optical depth2.62
27 Jun30 Jun3 Jul6 Jul9 Jul
Good Fair Moderate Poor Very poor Extremely poor

Particles from the Copernicus CAMS model at the centre of the perimeter; these are not measurements in each town. The pale bar is the worst hour, the solid one the daily average.

Open-Meteo.com (CC BY 4.0) · Copernicus Atmosphere Monitoring Service (CAMS)

Detections table · 2,864Every 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 Aspen Acres Fire last?
The official perimeter only gives the start date (29 June 2026). The end comes from the heat detections inside the perimeter: it burned until 16 July 2026 (18 days from 29 June 2026), 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 41,279 hectares (412.8 km²). Other tallies, such as daily incident reports, may give slightly different figures.
Which counties burned?
The fire entered 3 counties: Custer (42,627 ha, 22 %); Pueblo (40,776 ha, 6.5 %); Huerfano (49 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 31.0 °C, humidity dropped to 3 % and gusts hit 70 km/h. The fire danger index (FWI) reached 67, 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.
How did the fires that started in similar weather in this area end?
Fires less than 250 km away that started since 2016 with a similar FWI, humidity and dry spell: 19. Their median duration was 4 days and their median area 721 ha; 37 % went past 1,000 ha. Only 1 of its 19 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In 1 of 19, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 2.7 mm.

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 · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 6 July 2026 → 16 July 2026.

RSS Changes to this page With cross-checks and a citable version

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
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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.

How we know this
  • Perimeter: NIFC WFIGS (United States), 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. 2,864 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.
  • Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2025, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.

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.