TCS London Marathon weather.
Typically 10°C on race morning; dry every year. Race morning (07:00 to 11:00 local time) in London on race day in each of the last 10 years; the 2027 race is on 25 Apr 2027.
- Typical
- 10°C (50°F)
- race-morning average
- Coolest
- 3°C (37°F)
- lowest reading, 07:00–11:00
- Warmest
- 19°C (66°F)
- highest reading, 07:00–11:00
- Wet years
- 0 of 10
- rain, drizzle or worse
- Humidity
- 77%
- typical
- Wind
- 12 km/h
- typical, at 10 m
Race morning, 07:00–11:00
Year by year
| Race day | Average | Low–high | Humidity | Wind | Rain | Conditions |
|---|---|---|---|---|---|---|
| 25 Apr 2026 | 8°C (47°F) | 5°C (40°F)–13°C (56°F) | 76% | 4 km/h | 0.0 mm | Overcast |
| 26 Apr 2025 | 12°C (53°F) | 9°C (47°F)–15°C (59°F) | 78% | 8 km/h | 0.0 mm | Overcast |
| 27 Apr 2024 | 8°C (46°F) | 7°C (44°F)–9°C (48°F) | 86% | 20 km/h | 0.1 mm | Overcast |
| 22 Apr 2023 | 7°C (44°F) | 3°C (37°F)–11°C (51°F) | 89% | 4 km/h | 0.0 mm | Overcast |
| 23 Apr 2022 | 12°C (54°F) | 11°C (51°F)–15°C (58°F) | 72% | 26 km/h | 0.0 mm | Overcast |
| 24 Apr 2021 | 10°C (50°F) | 6°C (42°F)–13°C (56°F) | 68% | 16 km/h | 0.0 mm | Partly cloudy |
| 25 Apr 2020 | 10°C (50°F) | 7°C (45°F)–13°C (55°F) | 77% | 13 km/h | 0.0 mm | Overcast |
| 27 Apr 2019 | 9°C (48°F) | 8°C (46°F)–11°C (51°F) | 65% | 37 km/h | 0.0 mm | Overcast |
| 21 Apr 2018 | 15°C (58°F) | 11°C (51°F)–19°C (66°F) | 78% | 11 km/h | 0.0 mm | Mainly clear |
| 22 Apr 2017 | 10°C (50°F) | 9°C (48°F)–11°C (51°F) | 76% | 11 km/h | 0.0 mm | Overcast |
Each row is the race's date that year where we know it, else the same weekday nearest its usual date. Temperatures and humidity are averaged over 07:00 to 11:00 local time, rain is the total over those hours, and conditions are the commonest over the morning. The marathon starts at 09:30.
Kit and pacing
What it means
Good racing weather
Around 10°C is close to ideal for a fast time. Shorts and a vest are enough once you're moving; bring a throwaway layer for the wait in the start pen.
It can be cold
The coolest morning here dropped to 3°C. Pack gloves and a throwaway layer even if the forecast looks kind.
Expect wind
Wind was 12 km/h on a typical morning here. Run in a group on exposed stretches, and aim for even effort rather than even splits: time lost into a headwind isn't all won back with it behind you.
The weather varies a lot
Race mornings here have ranged by 8°C from year to year. Pack for both, and settle your kit and pacing from the forecast in the last few days.
General guidance from past years' numbers. Check the forecast in race week.
Weather data by Open-Meteo.com, from its historical weather archive (CC BY 4.0).