Race Day Weather
39°
54° high
Breezy
Dry
Cool and calm, ideal running
Runners will face a steady temperature rise from 41°F to 54°F, with average humidity at 56% and a dew point of 31°F. Winds will be from the S at 11 mph with gusts up to 24 mph. With favorable conditions, runners can maintain their pace without adjustments, ensuring hydration is a priority as temperatures increase.
Race day forecast available in 2 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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