Ottawa Marathon

Ottawa, ON, Canada · May 24, 2026

55°·67° high·Breezy·Dry

Weather

Pace Calc

Race Day Weather

55°at start

69° high

Breezy

Dry

Comfortable temps, warming through the race

Mild 55°F temps at gun time mean comfortable early miles without overheating risk. Temperatures rising to 69°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 26 days

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Pace Calculator

Distance: 26.2mi

Target Finish Time

0:00:00

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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 2026 Ottawa Marathon?

The 2026 Ottawa Marathon will be held on Sunday May 24, 2026.

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 2026 Ottawa Marathon?

The forecast calls for a high of 69°F and a low of 53°F with a 0% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.

Historical Weather

Based on 19 years of data

Avg Temp

70°F

L:55° H:70°

RunScore

Conditions

Rain Freq

21%

4 of 19 yrs

Wind9mph

Dew49°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2025 Ottawa Marathon Clear conditions throughout the day with rain. 2025	48°/64°	-	45°
2024 Ottawa Marathon Partly cloudy throughout the day with early morning rain. 2024	58°/67°	-	53°
2023 Ottawa Marathon Clear conditions throughout the day. 2023	59°/81°	-	45°
2022 Ottawa Marathon Partly cloudy throughout the day with rain clearing later. 2022	58°/67°	Light	51°
2019 Ottawa Marathon Partly cloudy throughout the day with early morning rain. 2019	62°/70°	-	56°
2018 Ottawa Marathon Partly cloudy throughout the day with early morning rain. 2018	57°/69°	-	49°
2017 Ottawa Marathon Partly cloudy throughout the day. 2017	57°/75°	-	53°
2016 Ottawa Marathon Partly cloudy throughout the day with rain. 2016	64°/82°	-	59°
2015 Ottawa Marathon Partly cloudy throughout the day. 2015	53°/80°	-	42°
2014 Ottawa Marathon Partly cloudy throughout the day. 2014	52°/75°	-	54°
2013 Ottawa Marathon Partly cloudy throughout the day. 2013	47°/60°	-	34°
2012 Ottawa Marathon Partly cloudy throughout the day. 2012	57°/72°	-	45°
2011 Ottawa Marathon Cloudy skies throughout the day with rain in the morning and afternoon. 2011	61°/68°	Light	62°
2010 Ottawa Marathon Cloudy skies throughout the day with early morning rain. 2010	61°/66°	-	49°
2009 Ottawa Marathon Partly cloudy throughout the day with morning rain. 2009	57°/69°	Light	48°
2008 Ottawa Marathon Partly cloudy throughout the day. 2008	50°/71°	-	39°
2007 Ottawa Marathon Cloudy skies throughout the day with rain. 2007	52°/54°	Light	51°
2005 Ottawa Marathon Cloudy skies throughout the day with late afternoon rain. 2005	53°/68°	-	53°
2004 Ottawa Marathon Clear conditions throughout the day. 2004	45°/65°	-	38°

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