Casper Half Marathon

Casper, WY, USA · June 6, 2027·

51°·58° high·Light·Dry

Weather

Casper Half Marathon race day weather

51°at start

71° high

Breezy

Dry

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Comfortable temps, big temp swing

Mild 51°F temps at gun time mean comfortable early miles without overheating risk. Temps will climb significantly to 71°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing.

Race day forecast available in 196 days

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Distance: 13.1mi

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About the Casper Half Marathon

The Casper Marathon half marathon runs 13.1 miles on the first Sunday in June, starting at the WYO Sports Ranch in Casper, Wyoming. The loop-out-and-back route follows the Platte River Trails system through the city on mostly asphalt, with some concrete sections, and ends at Crossroads Park.

Website

Race weekend

Sunday, June 6

6:00 AMMarathon (26.2 mi)

6:00 AMHalf Marathon (13.1 mi)

6:00 AM10K (6.2 mi)

Course Map

Casper Half Marathon FAQ

When is the 2027 Casper Half Marathon?

The 2027 Casper Half Marathon will be held on Sunday June 6, 2027.

What is the time limit for the Casper Half Marathon?

The time limit for the Casper Half Marathon is 6.5 hours.

What will the weather be like for the 2027 Casper Half Marathon?

The forecast calls for a high of 73°F and a low of 49°F with a 7% chance of rain. Check our detailed hourly forecast above for the best half marathon race plan.

What is the weather usually like for the Casper Half Marathon?

Over the 23 years racecast.io has race-day weather for (2003 to 2026), it averaged 48°F at the start and 58°F by a typical finish. Rain fell during race hours in 2 of those years (2014 and 2015).

What was the hottest Casper Half Marathon?

Of the 23 years on record, 2004 was the warmest, reaching 73°F during race hours. The coldest start was 2013, at 36°F.

What was the windiest Casper Half Marathon?

Of the 23 years on record, 2008 was the windiest, with wind averaging 15 mph during race hours. The calmest was 2025, at 0 mph.

Casper Half Marathon weather history

Based on 23 years of data

Avg Temp

53°F

L:47° H:58°

RunScore

Conditions

Rain Freq

2 of 23 yrs

Wind6mph

Dew44°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Casper Half Marathon Clear conditions throughout the day. 2026	51°/67°	-	47°
2025 Casper Half Marathon Clear conditions throughout the day with late afternoon rain. 2025	47°/61°	-	43°
2024 Casper Half Marathon Becoming cloudy in the afternoon with afternoon rain. 2024	56°/61°	-	42°
2023 Casper Half Marathon Partly cloudy throughout the day with afternoon rain. 2023	52°/56°	-	53°
2022 Casper Half Marathon Becoming cloudy in the afternoon. 2022	51°/60°	-	46°
2021 Casper Half Marathon Clear conditions throughout the day. 2021	57°/63°	-	45°
2019 Casper Half Marathon Clear conditions throughout the day. 2019	44°/57°	-	48°
2018 Casper Half Marathon Clear conditions throughout the day. 2018	39°/53°	-	39°
2017 Casper Half Marathon Clear conditions throughout the day. 2017	46°/61°	-	45°
2016 Casper Half Marathon Partly cloudy throughout the day. 2016	48°/58°	-	43°
2015 Casper Half Marathon Partly cloudy throughout the day with rain clearing later. 2015	53°/58°	Light	51°
2014 Casper Half Marathon Partly cloudy throughout the day with rain. 2014	44°/53°	Light	46°
2013 Casper Half Marathon Clear conditions throughout the day. 2013	36°/51°	-	36°
2012 Casper Half Marathon Clear conditions throughout the day with afternoon rain. 2012	53°/62°	-	45°
2011 Casper Half Marathon Clear conditions throughout the day. 2011	45°/58°	-	45°
2010 Casper Half Marathon Clear conditions throughout the day. 2010	43°/54°	-	44°
2009 Casper Half Marathon Cloudy skies throughout the day with rain. 2009	41°/43°	-	40°
2008 Casper Half Marathon Partly cloudy throughout the day. 2008	36°/47°	-	29°
2007 Casper Half Marathon Clear conditions throughout the day. 2007	40°/54°	-	45°
2006 Casper Half Marathon Clear conditions throughout the day. 2006	48°/60°	-	46°
2005 Casper Half Marathon Clear conditions throughout the day. 2005	45°/56°	-	41°
2004 Casper Half Marathon Clear conditions throughout the day. 2004	63°/73°	-	38°
2003 Casper Half Marathon Partly cloudy throughout the day with late afternoon rain. 2003	50°/56°	-	49°

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