Emirates Team New Zealand take NZL5 out on on the bay for the fourth day of testing and practice in San Francisco. 29/5/2013
Emirates Team New Zealand's meteorologist Roger ‘Clouds’ Badham, gives an outstanding overview of the course and conditions, to be expected on San Francisco Bay.
San Francisco Bay is one of the most challenging places to sail there is, and that’s just on any normal boat let alone an AC72.
When the teams line up to race on the course they will have a lot more than each other to worry about.
'First there is the mechanical challenges the teams face just to sail these boats, but then there is the physical strategy of where to put the boat on the race course. Where is the wind the strongest, where is the tide the most favorable and its changing minute by minute let alone leg by leg.' explains Clouds.
Typically on the San Francisco Bay the wind is from the west and arrives as a very strong sea breeze. It kicks off mid to late morning and peaks mid to late afternoon.
But wind isn’t all the afterguard on the Emirates Team New Zealand have to worry about explains Clouds, 'We also have tide or current. There is the North Bay to the north and South Bay around the corner, they are huge bay’s with an enormous volume of water that has to come in and out through the bay and under the Golden Gate Bridge where it can easily be three or four knots as a slow tide or up to six or seven knots at times.'
Illustrating the intricacies of the bay only a short distance away from the Golden Gate Bridge is the where the racing action starts and the difference in current can be a number of knots.
What is obvious to see while observing the Bay is that boat speed and handling aren’t the only things that will establish the winner of races from one day to the next.