Ottawa Marathon

Ottawa, ON, Canada · May 30, 2027

59°·71° high·Light·Dry

Weather

Race Day Weather

59°at start

75° high

Breezy

Dry

Your goal

0:00:00

to see the forecast where you'll be

Comfortable temps, big temp swing

Mild 59°F temps at gun time mean comfortable early miles without overheating risk. Temps will climb significantly to 75°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 228 days

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Distance: 26.2mi

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Race Info

The Tartan Ottawa International Marathon is Canada’s fastest marathon. This race attracts thousands of participants, including a world-class contingent of pro-athletes every year. The Tartan Ottawa International Marathon is a World Athletics Elite Label Race and one of Canada’s largest Boston Qualifiers. Source

Website

Course Map

FAQ

When is the 2027 Ottawa Marathon?

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

Is the Ottawa Marathon a Boston Marathon Qualifier?

Yes, the Ottawa Marathon is an official Boston Marathon qualifier.

What will the weather be like for the 2027 Ottawa 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 marathon race plan.

Historical Weather

Based on 20 years of data

Avg Temp

59°F

L:55° H:64°

RunScore

Conditions

Rain Freq

20%

4 of 20 yrs

Wind7mph

Dew49°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Ottawa Marathon Cloudy skies throughout the day with early morning rain. 2026	52°/52°	Light	49°
2025 Ottawa Marathon Clear conditions throughout the day with rain. 2025	48°/58°	-	46°
2024 Ottawa Marathon Partly cloudy throughout the day with early morning rain. 2024	58°/65°	-	52°
2023 Ottawa Marathon Clear conditions throughout the day. 2023	59°/71°	-	44°
2022 Ottawa Marathon Partly cloudy throughout the day with rain clearing later. 2022	58°/62°	Light	52°
2019 Ottawa Marathon Partly cloudy throughout the day with early morning rain. 2019	62°/67°	-	58°
2018 Ottawa Marathon Partly cloudy throughout the day with early morning rain. 2018	57°/62°	-	46°
2017 Ottawa Marathon Partly cloudy throughout the day. 2017	57°/71°	-	54°
2016 Ottawa Marathon Partly cloudy throughout the day with rain. 2016	64°/71°	-	56°
2015 Ottawa Marathon Partly cloudy throughout the day. 2015	53°/70°	-	42°
2014 Ottawa Marathon Partly cloudy throughout the day. 2014	52°/69°	-	53°
2013 Ottawa Marathon Partly cloudy throughout the day. 2013	47°/52°	-	35°
2012 Ottawa Marathon Partly cloudy throughout the day. 2012	57°/67°	-	45°
2011 Ottawa Marathon Cloudy skies throughout the day with rain in the morning and afternoon. 2011	61°/63°	Light	61°
2010 Ottawa Marathon Cloudy skies throughout the day with early morning rain. 2010	61°/61°	-	48°
2009 Ottawa Marathon Partly cloudy throughout the day with morning rain. 2009	57°/64°	Light	49°
2008 Ottawa Marathon Partly cloudy throughout the day. 2008	50°/66°	-	41°
2007 Ottawa Marathon Cloudy skies throughout the day with rain. 2007	52°/54°	-	49°
2005 Ottawa Marathon Cloudy skies throughout the day with late afternoon rain. 2005	53°/66°	-	54°
2004 Ottawa Marathon Clear conditions throughout the day. 2004	45°/62°	-	38°