Talkback radio host Ben Fordham has rushed to the aid of a windsurfer who found themselves in trouble during a day out on Sydney Harbour.

2GB breakfast host Fordham was about to attend the wedding reception of producer Liam McGuire on Friday afternoon when he heard whistling near Woolwich Dock.

Fordham looked over to the water, noticed a group in trouble and rushed over to help with several other wedding guests.

"They were still in the water with a windsurf and it was tipped over," he said.

"I yelled out to him 'do you want help?' and he said 'yes'."

Several people pulled windsurfer Jonah Aiello onto the dock, after he went out into choppy waters with friends.

"What went wrong was the decision to go out," Aiello told 2GB this morning.

"We knew the forecast, we knew what we were g

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