Please select your home edition
Edition
Ancasta Ker 33 728x90

Louis Vuitton Cup- Predictwind - Strong winds despite changed start

by Richard Gladwell on 19 Aug 2013
Luna Rossa Challenge 2013 Louis Vuitton Cup Final - Race 2 Red Moon/ Studio Borlenghi / Borlenghi-Butto

Predictwind indicates that winds will be just under the limit for racing in the third and fourth races of the Finals for the Louis Vuitton Cup between Italian Challenger Luna Rossa, and Emirates Team New Zealand when they meet on Monday August 19, 2013 in San Francisco.

On Sunday, official bought the start time forward by an hour to try and get lighter winds and enable racing within the limit of 18-19kts (depending on the state of the tide). The first 25 minute race is due to start at 1210hrs local time, with the second about an hour later.

The top image shows the wind speed and direction at 1215hrs with one feed showing winds of 15kts while the other is at 18kts - these are only average speeds and gusts will be higher. There is a small amount of variation in the prognosis, with the point of disagreement being in the rate of increase of the breeze, rather than the actual strength. The breeze peaks at about 1500hrs (3.00pm local time) at a speed of around 23kts - well in excess of the wind limit, but interestingly within the limit of 25kts for the America's Cup.

The prediction indicates that the winds should just be within the limit for the first race, but the second race of the day is marginal.

The second image shows a graphic representation of the wind build - confirming the numbers for the prognosis.



The next two images are showing the same style of information except for an hour later around the time of the second race for the day. Winds are creeping very close to the limit, and bearing in mind that these are only average windspeeds with no accounting for gusts, it is likely that the wind limit will be exceeded on the current wind information.



The fifth chart shows the wind exceptions for the following day, which shows a reduction in the strength of the breeze, allowing officials some scope to catch-up if required.


Two weather feeds are used by Predictwind, the key to the accuracy of the forecast lies with the graphs, as when the two lines for the two feeds are quite close together and following each other in the trend, then the likelihood of the forecast is high. If there is separation to any marked degree, then there still some issues to be resolved but usually 24 hours from the race they are well aligned.

The Predictwind model takes various weather feeds and then polishes these, part of this process is factoring in the effect of local topography on the breeze - well demonstrated by the image with the funneling of the breeze.

Developed by former Olympian, Jon Bilger (470, 1992), www.predictwind.com!PredictWind application was used by the Swiss team Alinghi to win the 2003 and 2007 America's Cups, and has become the leading wind system used by racing and recreational sailors around the world. It is available on a subscription basis and also with a free forecast option.

A mobile app for Android and iPhone is available and www.predictwind.com!PredictWind is probably the most used app on the Sail-World iPhone.

Real time local wind observations have been added as further functionality.

You can check the weather anywhere in the world, and get a five day forecast, plus a variety of other features and functions of www.predictwind.com!PredictWind. The app is synchronised with your PC, so that your latest set of locations are always available without resetting each time you change a device.

Ancasta Ker 40+ 660x82Wildwind 2016 660x82Colligo Marine 660x82

Related Articles

Rio 2016 - Plain speaking by triple-medalist on Olympic sailing moves
Triple Olympic medalist, Santiago Lange has been on the sharp end of changes made to Olympic classes and formats Santiago Lange, a six-time Olympian and Bronze medallist in the 2004 and 2008 Olympics, won his third medal – Gold sailing in the Nacra 17 class. With that length of experience at an Olympic level, having sailed the Laser, Tornado and now Nacra 17 classes his comments on the future shape of the Olympic regatta was one of the highlights of the Medallists Media Conferences.
Posted today at 5:58 am
An Q&A with Steve and Heidi Benjamin about the NYYC’s 2016 Queen’s Cup
Sail-World caught up with Steve and Heidi Benjamin to learn more about Heidi’s historic win in the NYYC’s Queen’s Cup. When it comes to U.S. Grand Prix sailing, it’s hard not to encounter the names of Steve and Heidi Benjamin. The two highly polished sailors have been successfully campaigning their series of yachts, named SPOOKIE, for years, starting first with a Carkeek 40 and progressing to their TP52. I caught up with Steve and Heidi to learn more about Heidi’s historic win in the NYYC’s Queen’s Cup
Posted on 19 Aug
Rio 2016 - Images of the penultimate race in the Finns - Scott wins
Sail-World's Richard Gladwell was on the water for the final race of the Qualifying Series of the Mens Finn Sail-World's Richard Gladwell was on the water for the final race of the Qualifying Series of the Mens Finn, in what potentially could have been Giles Scott's (GBR) Gold medal winning race. In the end, the current world champion won in style.
Posted on 15 Aug
Rio 2016 - Images from the Mens RS:X Medal Race
Sail-World's NZ Editor, Richard Gladwell, was on the water at the Medal Race for the RS:X class Sail-World's NZ Editor, Richard Gladwell, was on the water at the Medal Race for the RS:X class won before the race by Dorian van Rijsselberghe (NED) without needing points from the Medal Race. Nick Dempsey (GBR) was second on a similar basis.
Posted on 15 Aug
Rio 2016 - Sailors talk of Life at the Extreme on the Atlantic Ocean
Certainly the Volvo Ocean Race catchcry of Life at the Extreme is not a phrase associated with the Sailing Olympics. The 470 crews were suffering the mixed emotions of survival of an extreme test by nature, the cold, and for some elation at their placings, after Thursday's battle for survival. In conditions that looked more out of the Volvo Ocean Race, than an Olympic sailing regatta, crews battled 20kt plus winds and Atlantic Ocean rollers that towered up to four metres.
Posted on 13 Aug
Rio Olympics - Fourth gallery of images the fearsome Niteroi course
Fourth image gallery from racing on Day 4 in the Mens and Womens 470 class on the Niteroi course in the Atlantic Ocean Fourth image gallery from racing on Day 4 in the Mens and Womens 470 class on the Niteroi course in the Atlantic Ocean - sailing in 3-4 metre swells and 20kt plus winds. believe it or not the sea conditions were worse inshore as the fleet encountered the backwashed Atlantic rollers
Posted on 12 Aug
Rio 2016 - Third image gallery of 470's braving the Atlantic Ocean
Third image gallery from racing on Day 4 in the Mens and Womens 470 class on the Niteroi course in the Atlantic Ocean Third image gallery from racing on Day 4 in the Mens and Womens 470 class on the Niteroi course in the Atlantic Ocean - sailing in 3-4 metre swells and 20kt plus winds
Posted on 12 Aug
Gladwell's Line - The challenges of Guanbara Bay
The decision to run Medal Racing on the Pao de Acucer course, probably won't be remembered as one of the brightest The decision to run Medal Racing on the Pao de Acucer, probably won't be remembered as one of the brightest of the 2016 Sailing Olympics. Over shadowed by a 1300ft tall granite and quartz mountain in the shape of a sugarloaf, the bay suffers from dramatic windshifts, and huge variance in wind pressure.
Posted on 11 Aug
Rio 2016 - Fresher breezes expected inside and outside on Day 3
Stronger winds are expected for the third day of racing in the 2016 Olympic Sailing Regatta in Rio de Janeiro. Stronger winds are expected for the third day of racing in the 2016 Olympic Sailing Regatta in Rio de Janeiro. Two of the fleet scheduled to race outside on the Atlantic Ocean course off Copacabana Beach, while the 470 Men and Women will race inside on Guananara Bay.
Posted on 10 Aug
Rio 2016 - Day 2 brings more tumult for some, salvation for others
The course area may have changed, but Brit, Nick Dempsey's performance early on stayed the same. The course area may have changed, but Brit, Nick Dempsey's performance early on stayed the same. He picked up where he left off on Day 1 in Race 4 of the Men's RS:X class on the Escola Naval race area to record his third win in four races. Poland's Piotr Myszka finished second with Brazil's Ricardo Santos third.
Posted on 10 Aug