Ottawa Half Marathon

Starting at 63°F, heat will be a factor from the gun — go out conservative and stay on top of hydration. Temperatures rising to 75°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing.

Race day forecast available in 212 days

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Distance: 13.1mi

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Race Info

The Ottawa Half Marathon runs 21.1 km on the Sunday of race weekend, starting at Ottawa City Hall. The course crosses the Ottawa River into Gatineau and returns to the capital past Parliament Hill, the Canadian Museum of History and Rideau Hall, finishing along Queen Elizabeth Drive beside the Rideau Canal. It is a fast, relatively flat course that suits personal bests and first half marathons.

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Race weekend

Saturday, May 29

3:00 PM2K (1.2 mi)

4:00 PM5K (3.1 mi)

6:00 PM10K (6.2 mi)

Sunday, May 30

7:00 AMMarathon (26.2 mi)

9:00 AMHalf Marathon (13.1 mi)

FAQ

When is the 2027 Ottawa Half Marathon?

The 2027 Ottawa Half Marathon will be held on Sunday May 30, 2027.

What is the time limit for the Ottawa Half Marathon?

The time limit for the Ottawa Half Marathon is 4 hours.

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

The forecast calls for a high of 74°F and a low of 53°F with a 11% chance of rain. Check our detailed hourly forecast above for the best half marathon race plan.

Historical Weather

Based on 20 years of data

Avg Temp

61°F

L:59° H:64°

RunScore

Conditions

Rain Freq

1 of 20 yrs

Wind7mph

Dew48°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Ottawa Half Marathon Cloudy skies throughout the day with early morning rain. 2026	52°/52°	Light	49°
2025 Ottawa Half Marathon Clear conditions throughout the day with rain. 2025	54°/58°	-	46°
2024 Ottawa Half Marathon Partly cloudy throughout the day with early morning rain. 2024	61°/65°	-	52°
2023 Ottawa Half Marathon Clear conditions throughout the day. 2023	64°/71°	-	43°
2022 Ottawa Half Marathon Partly cloudy throughout the day with rain clearing later. 2022	60°/62°	-	50°
2019 Ottawa Half Marathon Partly cloudy throughout the day with early morning rain. 2019	65°/67°	-	56°
2018 Ottawa Half Marathon Partly cloudy throughout the day with early morning rain. 2018	58°/62°	-	48°
2017 Ottawa Half Marathon Partly cloudy throughout the day. 2017	65°/71°	-	54°
2016 Ottawa Half Marathon Partly cloudy throughout the day with rain. 2016	67°/71°	-	58°
2015 Ottawa Half Marathon Partly cloudy throughout the day. 2015	59°/70°	-	43°
2014 Ottawa Half Marathon Partly cloudy throughout the day. 2014	60°/69°	-	55°
2013 Ottawa Half Marathon Partly cloudy throughout the day. 2013	49°/52°	-	34°
2012 Ottawa Half Marathon Partly cloudy throughout the day. 2012	61°/67°	-	44°
2011 Ottawa Half Marathon Cloudy skies throughout the day with rain in the morning and afternoon. 2011	63°/63°	-	61°
2010 Ottawa Half Marathon Cloudy skies throughout the day with early morning rain. 2010	61°/61°	-	48°
2009 Ottawa Half Marathon Partly cloudy throughout the day with morning rain. 2009	62°/64°	-	47°
2008 Ottawa Half Marathon Partly cloudy throughout the day. 2008	58°/66°	-	40°
2007 Ottawa Half Marathon Cloudy skies throughout the day with rain. 2007	54°/54°	-	49°
2005 Ottawa Half Marathon Cloudy skies throughout the day with late afternoon rain. 2005	57°/66°	-	54°
2004 Ottawa Half Marathon Clear conditions throughout the day. 2004	56°/62°	-	37°

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