Great Welsh Marathon
Race Day Weather
Cool temps, light rain expected
Runners will face a consistent temperature of 48°F to 50°F, with high humidity at 96%. Light rain is anticipated throughout the race, necessitating careful footing. With winds from the SE at 8 mph, runners should maintain a steady pace while considering hydration due to the humidity.
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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 |
|---|---|---|---|---|---|
2025 |  | 43°/51° | - | 33° | |
2024 | | 50°/54° | Light | 50° | |
2022 | | 51°/60° | - | 43° | |
2019 |  | 43°/50° | - | 30° | |
2018 | | 50°/54° | Light | 49° | |
2017 | | 54°/57° | - | 47° |