Race Day Weather
39°
54° high
Breezy
Dry
Cool start, steady conditions ahead
Runners will face a cool temperature trend starting at 41°F and rising to 54°F. Wind will be a light headwind at 11 mph, with gusts reaching 24 mph. With average humidity at 56%, runners can maintain their pace but should stay mindful of wind resistance, especially in exposed areas.
Race day forecast available in 23 days
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A Boston-qualifier marathon that follows the beautiful St Lawrence River from Crysler Park Marina to St. Lawrence College in Cornwall, Ontario. As well as Half-Marathon, 10km and 5km distances that follow the scenic Great Lakes Waterfront Trail. Source
FAQ
When is the 2026 St. Lawrence Marathon?
The 2026 St. Lawrence Marathon will be held on Saturday April 25, 2026.
Is the St. Lawrence Marathon a Boston Marathon Qualifier?
Yes, the St. Lawrence Marathon is an official Boston Marathon qualifier.
What will the weather be like for the 2026 St. Lawrence Marathon?
The forecast calls for a high of 54°F and a low of 38°F with a 0% chance of rain.
Historical Weather
Based on 4 years of data
Avg Temp
52°F
L:45° H:54°
RunScore
Conditions
Rain Freq
75%
3 of 4 yrs
Wind12mph
Dew40°F
Temperature History
Range of temperatures during race hours for each year.
Detailed History
| Year | Conditions | Low / High | Rain | Dew Point | Score |
|---|---|---|---|---|---|
2025 |  | 46°/50° | Light | 46° | |
2024 |  | 46°/71° | - | 30° | |
2023 | | 47°/55° | Light | 41° | |
2019 | | 39°/42° | Light | 34° |
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