Great Welsh Marathon
Race Day Weather
Comfortable temps, moderate wind
Mild 54°F temps at gun time mean comfortable early miles without overheating risk. Moderate winds around 14mph may affect pacing on open sections of the course. Moderate humidity at 78% is worth noting for effort level, especially in later miles.
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Race Info
Hosted at the magnificent Pembrey Country Park in Carmarthenshire this race showcases the best of coast and country on a route that covers both the half and full marathon distance. This is a race for everyone, so whether you love inspiring green spaces or are a sucker for coastal views, then you’ll run happy, as this has it all! Boasting a maximum elevation of only 18 metres and an overall gain of 110 metres for the full marathon distance, this race offers a superb opportunity to achieve your personal best! It’s the perfect spring race that is flat, friendly, and great for first-timers or PB chasers! Source
Historical Weather
Temperature History
Range of temperatures during race hours for each year.
Detailed History
| Year | Conditions | Low / High | Rain | Dew Point | Score |
|---|---|---|---|---|---|
2026 | | 48°/50° | Light | 48° | |
2025 |  | 38°/50° | - | 33° | |
2024 |  | 50°/54° | Light | 50° | |
2022 | | 50°/58° | - | 43° | |
2019 |  | 41°/50° | - | 30° | |
2018 | | 50°/54° | Light | 49° | |
2017 | | 54°/57° | - | 47° |