That Dam Hill Marathon

London, ON, Canada · September 19, 2026

57°·67° high·Breezy·Dry

Weather

Race Day Weather

57°at start

67° high

Breezy

Dry

Cool start, warming trend ahead

Runners will face temperatures starting at 58°F and rising to 68°F. With average humidity at 72%, hydration will be crucial throughout the race. Wind will be light, with a maximum of 9 mph from the SE, making it a non-factor. Runners should consider adjusting their pace as the temperature climbs.

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Distance: 26.2mi

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Race Info

That Dam Hill Marathon in London, Ontario, offers a certified Boston Marathon Qualifier course that is both spectator-friendly and ideal for setting personal bests. The event features a variety of race options, including a marathon, half marathon, and multiple timed ultra races, all set within the scenic Springbank Park. Organized by dedicated volunteers, the race supports cancer research, with all net proceeds benefiting the Dunn with Cancer charity.

Website

Course Map

FAQ

When is the 2026 That Dam Hill Marathon?

The 2026 That Dam Hill Marathon will be held on Saturday September 19, 2026.

Is the That Dam Hill Marathon a Boston Marathon Qualifier?

Yes, the That Dam Hill Marathon is an official Boston Marathon qualifier.

What will the weather be like for the 2026 That Dam Hill Marathon?

The forecast calls for a high of 70°F and a low of 57°F with a 7% chance of rain.

Historical Weather

Based on 7 years of data

Avg Temp

72°F

L:54° H:72°

RunScore

Conditions

Rain Freq

14%

1 of 7 yrs

Wind8mph

Dew50°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2025 That Dam Hill Marathon Partly cloudy throughout the day. 2025	54°/73°	-	44°
2024 That Dam Hill Marathon Partly cloudy throughout the day with rain clearing later. 2024	63°/82°	-	63°
2023 That Dam Hill Marathon Partly cloudy throughout the day. 2023	48°/69°	-	50°
2022 That Dam Hill Marathon Partly cloudy throughout the day. 2022	59°/79°	-	63°
2021 That Dam Hill Marathon Partly cloudy throughout the day. 2021	61°/74°	-	54°
2020 That Dam Hill Marathon Clear conditions throughout the day with morning rain. 2020	36°/59°	Light	34°
2019 That Dam Hill Marathon Partly cloudy throughout the day. 2019	58°/70°	-	54°