The devastated crew of three yachts have been forced to retire from the Sydney to Hobart less than an hour into the race.
More than 100 yachts have left Sydney harbour on Boxing Day, leaving behind yachts Ark323, Cougar II and Lupa of London that have returned defeated.
Ark323 collided with a rival boat just 300 metres into the race and was forced to retire, although the other yacht has kept going.
Meanwhile, a rear corner of Cougar II has been ripped apart and a crew member has been injured with cuts around his eyes.
Businessman Peter Hickson's M3 from Western Australia has returned to port with a broken forestay, but has not retired.
The crew have been assessing damage and have four hours to return to the race.
Blue skies turned to grey in the minutes before the horn sounded for the 1pm start.
The traditional cannon wasn't fired after the official start boat was forced into an emergency evacuation of its passengers.
An old-school horn kicked off the race instead, along with flags.
The dramatic opening was witnessed by thousands who lined the harbour foreshore to glimpse the magnificent fleet set sail.
Race competitors had a decent tail wind to start but later in the day many could be hit with storms as a vigorous cold front moves in from south of Adelaide, according to the Bureau of Meteorology.
"They may encounter some of these storms as they head south," BOM meteorologist Stephen Stefanac told AAP.
For the second part of the race the BOM has predicted southerly winds, making it "a little more difficult".
Crowds made the most of the sunshine before rain hit Sydney two hours following the start.
"I want a blue boat to win, because I like blue," four-year-old Belle said.
British tourist Judy Rogers said the anticipation had been building all day.
"I've never seen anything like it," she said while touring along pontoons at the Cruising Yacht Club of Australia at Rushcutters Bay.
