The 2025 event has concluded.

All-Out Fallfest Half Marathon

Westminster, CO, USA • September 13, 2025
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rain Clear conditions throughout the day with rain.

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When is the 2025 All-Out Fallfest Half Marathon?

The 2025 All-Out Fallfest Half Marathon will be held on Saturday September 13, 2025.

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Historical Weather & Results

RunScore
Run Score: 8
Temp
78°F
Min/Max
54°/78°F
Dew
33°F
Days of Rain
1/8
Wind
5mph
Tap a row for details.
YearLow / HighRain

All-Out Fallfest Half Marathon 2024 Weather History

Clear conditions throughout the day.

2024
clear-day
59°/ 87°-
Run Score: 8

All-Out Fallfest Half Marathon 2022 Weather History

Partly cloudy throughout the day with afternoon rain.

2022
clear-day
55°/ 76°-
Run Score: 8

All-Out Fallfest Half Marathon 2021 Weather History

Clear conditions throughout the day.

2021
clear-day
51°/ 88°-
Run Score: 7

All-Out Fallfest Half Marathon 2020 Weather History

Clear conditions throughout the day.

2020
clear-day
58°/ 83°-
Run Score: 8

All-Out Fallfest Half Marathon 2019 Weather History

Becoming cloudy in the afternoon.

2019
clear-day
56°/ 75°-
Run Score: 8

All-Out Fallfest Half Marathon 2018 Weather History

Clear conditions throughout the day.

2018
clear-day
53°/ 85°-
Run Score: 8

All-Out Fallfest Half Marathon 2017 Weather History

Partly cloudy throughout the day with rain.

2017
cloudy
48°/ 52°Light
Run Score: 9

All-Out Fallfest Half Marathon 2015 Weather History

Clear conditions throughout the day.

2015
clear-day
52°/ 81°-
Run Score: 8
You Need an Account For That

Setting up a racecast.io account will allow you to start building a reputation in the community. Over time you'll be able to rate races, join the discussion, and post in the community.

Right now we are invite only, you can get on the waitlist by entering your email below:

OR
You Need an Account For That

Setting up a racecast.io account will allow you to start building a reputation in the community. Over time you'll be able to rate races, join the discussion, and post in the community.

Right now we are invite only, you can get on the waitlist by entering your email below:

OR