Cardiff Half Marathon
Race Day Weather
Mild temps, shifting winds ahead
Runners will face a temperature range from 55°F to 61°F, with average humidity at 77%. Winds will start as a headwind in Mile 1, transitioning to a crosswind until Mile 4, followed by a favorable tailwind in Mile 5. It is recommended to adjust pacing early on and stay hydrated, especially with the wind shifts and humidity levels.
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Race Info
The Cardiff Half Marathon takes place in Cardiff, Wales, each October and ranks as the UK's second-largest half marathon behind the Great North Run. The course starts on Castle Street beside Cardiff Castle and finishes near Cardiff City Hall in Cathays Park, passing Cardiff Bay and Roath Park Lake along the way. World Athletics has held it as an Elite Label road race since 2017, and the course hosted the IAAF World Half Marathon Championships in 2016. The race began in 2003 and has grown from about 1,500 finishers to more than 27,000.
