Moderating as quickly as it began, the squall left a trail of destruction. Principal Race Officer, Ross Wilson, assessed the damage before deciding not to send the fleets back out. He said that race management continually monitors all the wind beacons around Port Phillip Bay and none of them gave any indication of the severity of the storm.
New Zealand 49er skipper, Peter Burling, told how the 49er and 29er fleets were flattened, with sailors in the water just hanging on and hoping they wouldn't be washed onto the rocks. Olympic Gold medalist Malcolm Page, one of the most experienced sailors in the fleet, said he and skipper Mat Belcher just kept heading to windward, trying everything to keep the boat upright.
This morning there was no indication of the dramas, with solid winds of 12 to 15 knots for the Laser, Finn and RS:X classes.
Laser sailor Nick Thompson went into the penultimate day in second place behind Australian Tom Burton, but three races later he was back in the rigging area with a nine point lead. World Champion Tom Slingsby came out of the blocks fastest, winning the first two races. But Thompson knew all he had to do was stay close. A second, a third and a win in the last race were more than enough to know only a disaster tomorrow can cost him the title.
"My tactics were to be conservative. Start well, use my speed," said Thompson. "The last race was more of a 'keep your eye out for both Toms'. We split a bit and that cost me but I worked my way back, so I'm pleased with that."
Thompson says his tactics will be the same tomorrow, aiming to stay out of trouble and cover Tom Burton, his only real threat.
Burton is a renowned light weather sailor and he struggled a little in the first two races, recording a 13th and a 22nd, before bouncing back to be second in the final race.
"I had a lot to think about," said the young Australian Sailing Development Squad member. "It's a lot harder to close out a regatta than to just get good race results." He remains upbeat about his prospects tomorrow but knows he is up against two much more experienced opponents. To become a full member of the Australian Sailing Team, he needs to stay ahead of Slingsby and finish second in the regatta. He has only a five point buffer over Slingsby and the medal race counts double points, meaning he can't let Slingsby beat him by more than two places.
In the Finn class it is a British benefit. Giles Scott was the best performed of the four Great Britain sailors with a scorecard of two, two, one, but his compatriot Ben Ainslie leads the series.
Scott said there were "big, winding shifts" out on the water which were quite easy to read. "It was nice to stretch the legs a little bit," Scott said, referring to the fact that the huge men who sail the Finns have been crouched in the boat for most of the first four days, instead of hiking out as they managed to do today.
Going into the Medal Race on Saturday, Ainslie is on 25 points, Scott is on 31 and Ed Wright is on 32.
In the RS:X women's class, Australian Jessica Crisp will take a three point lead into the Medal Race. Overnight she was one point behind Huali Zhu of China, but both sailors had poor races today, and Hualz's ninth and 13th dropped her behind the Australian.
However, in the men's event the Asian dominance was complete, with Ho Tsun Leung moving back into the lead ahead of China's Aichen Wang and Leung's Hong Kong teammate King Yin Chan. After a week of pumping races, Leung said there was "much better wind" for him out there today.
The 470 class was halfway through their second race when the storm hit. Mathew Belcher and Malcolm Page won the first one by half a boat length from Matthias Schmid and Florian Reichstädter and were leading in the second, but the Austrians will carry a one point lead into the medal round, over American's Stuart Mcnay and Graham Biehl, with the Australians a point further back. Effectively, this means Belcher and Page need to beat both crews to win the title.
With lower-ranked competitors doing well in the women's 470, as happened in so many classes with the change in wind conditions today, there was no change at the top. Austria leads from Germany, with the Chinese and the second German crew tied for third.
The 49er class will feature a two-way battle between the New Zealand pairing of Peter Burling and Blair Tuke, who won at Sail Sydney last week, and the Austrians Nico Delle - karth and Nikolaus Resch.
Australia won both races sailed today, with Nathan Outteridge and Iain Jensen taking the first, while brothers Will and Sam Phillips won the second.
Tomorrow the medal races will be sailed on Course B which can be viewed directly from the balcony at Sandringham Yacht Club with the event open to the public with a Family Day taking place. The forecast is for west to southwesterly winds at 15 to 20 knots tending south to southwesterly 10 to 15 knots during the afternoon. There is a chance of a thunderstorm in the morning.
All medal races will feature live tracking, which can be viewed at www.sailmelbourne.com.au. Full results for all races up to and including today, photos and videos are also available on the site.
For full results visit http://www.yachting.org.au/site/yachting/event/32737/default.html
Visit the ISAF Sailing World Cup YouTube site for video highlights on the Sail Melbourne 2010 playlist - www.youtube.com/sailingworldcup