Runners will face a temperature rise from 58°F to 75°F, accompanied by moderate humidity at 62%. Winds will be light at 8 mph from the WSW, with gusts up to 23 mph. Runners should start conservatively to manage the heat and adjust their pace as temperatures climb.
Race day forecast available in 261 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
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
69°F
L:55° H:69°
RunScore
Conditions
Rain Freq
25%
5 of 20 yrs
Wind9mph
Dew49°F
Temperature History
Range of temperatures during race hours for each year.
