Nearly two thousand people took part in the Great East swim - among them two Olympic swimmers who are hoping to go for gold in the open water events at London 2012.
Russell Hookey spent the day at Alton Water near Ipswich and saw the action:
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Cloudy skies with a southeasterly breeze picking up and rain reaching western counties by dusk, perhaps snow in places later.
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Some morning brightness on Boxing Day but cloud increasing, with rain, sleet and snow, spreading in late afternoon. Turning windy.