Avon & Somerset Police are appealing for spectators with video or photos of the fatal accident to contact them.
The crash happened as 23-year-old cyclist Junior Heffernan came round a bend during the Severn Bridge Road Race.
Here is Acting Inspector Darren Jarvis...
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Low cloud should break away by lunchtime to allow for some sunny spells and warm temperatures.
Few hours of murk and mist in the morning but sunshine should break up the low could to bring about warm temperatures by the afternoon.
It will be a misty and murky start to Wednesday morning but sunshine will soon break through to bring warmer temperatures in the afternoon.