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Downhill to New Zealand! Westerly winds are predicted to remain consistent for Club Med and Innovation Explorer right across the Southern Indian Ocean, but a blocking pattern is emerging under Australia. Will it affect the front-runners? January 25, 2001 Consistent westerly winds have provided something of a holiday for leading skippers aboard Club Med and Innovation Explorer. But read their reports coming through race headquarters and you will find they haven't let their guard down for a moment. In fact Club Med - which passed the Kerguelen Islands (long.70 lat. 50) yesterday morning, and is making about nine degrees of longitude each day - is navigating along a narrow band of optimum wind: 20-25 knots from the west, with slight shifts from north west to south west every time a front, imbedded in the westerly flow, moves past them. Innovation Explorer, 700 miles to the west and slightly south, would be doing the same, except that their sail wardrobe is less extensive - and deteriorates further every time their downwind reacher is hoisted to the top of the mast. They are under Solent jib at the moment, sailing higher angles to fill the darned thing, and have opted for stronger winds - 35-40 knots - coursing along an equally narrow slot further south. But even below the Antarctic Convergence - where cold polar water dives below warmer sub-Antarctic ocean, the swell is small - just three metres and helmsmen are complaining that these are too small to let their maxi cat stretch its legs ... and surf! Yesterday, Innovation Explorer fell into a hole, having tracked too far south for the weather conditions and found itself in light airs underneath an emerging low pressure cell. Club Med, meanwhile, looks like riding its westerly stream all the way to Australia before there is any change in conditions. What Of Team Adventure? After a quick repair job to their delaminated main beam (or is it their front beam? ... we've heard contrary reports ...) Team Adventure is due to depart Cape Town any moment now minus injured crew. But it faces a grueling slog south - against stiff south-east winds and then through the centre of a Southern Ocean High - to get into that handy westerly flow benefiting Club Med. Warta Polpharma, meanwhile, has dived south after finally negotatiating the trickiest of South Atlantic Highs and may well provide good racing for the re-built Team Adventure. We might see, at last, exactly how the the next generation of boats really affect multihull racing! Team Legato, poor blokes, are still trapped in the South Atlantic High but are gambling on a small low pressure cell, developing out of a monsoonal trough east of Uruguay, to give them a decent breath of wind ... © weather-wise.com 2001 Fleet positions Westerly flow gives fleet leaders, Club Med (blue line) and Innovation Explorer (green line) a steady ride. Note how Innovation Explorer has to zig-zag downwind. This is because their reaching sail is in poor shape, so they are sailing under Solent jib and need to maintain a higher angle to the wind to keep it filled. For the same reason, they have opted to sail south where stronger winds are expected Fleet positions Have a look at that 'dorsal' of weak low pressure directly north of Innovation Explorer. It is actually the birth of a low pressure cell and its associated front which will certainly push Club Med along nicely, but is delivering headwinds to Loick Peyron, Skip Novak and crew. Bob Rice has already told us that storms often form south-east of the African continent - one of several 'cyclogenesis' locations around the world. Note Warta Polpharma's crazy route (yellow line) through the South Atlantic High. Those in the know suggest they should have sailed south before they jibed east and might have escaped the high several days sooner. Well, that's how you learn! Picture courtesy of Virtual Spectator. Southern Indian Ocean Jet Stream Image courtesy of the Australian
Bureau of Meteorology The Kerguelen Islands are just visible in this chart, located at longitude 70, latitude 50 and Cub Med is just to their east. Note the slight sip in the jet about longitude 80 - signaling a frontal system at the surface. Chances are, Grant Dalton, Franck Proffitt and crew are still riding the westerly flow immediately behind this cold front and will continue to do so until they sail below Cape Leeuwin, Western Australia. They have been logging about nine degrees each day, so Sunday could see them at this point - all going well. At this point interference from the hot Australian desert and other factors can put kinks in the stream, as low pressure cells form at the surface. From this chart you can see a blocking situation forming below the Australian bight, with the jet stream tracking south of a high pressure cell at the surface. This is exactly the scenario which hampered the Sydney to Hobart Fleet after Christmas and challenged the Vendee Globe fleet about the same time. Whether this blocked high is as extreme remains to be seen, but models suggest that it may be plain sailing under the continent of Australia - see the animated COLA model below for more details. Southern Indian Ocean surface
pressure Image courtesy of the Australian Bureau of Meteorology. Looks different at the surface, eh? In fact, the two frontal systems shown clearly in bold pen here are shown subtly on the upper level map above. These are frontal systems embedded in a general westerly flow, moving faster than Club Med or Innovation Explorer would care to travel. However, Cub Med has been riding the back of a frontal system generated by a low - centred longitude 100, latitude 70 - for a few days now. Perhaps this low is moving slightly slower than those behind because it is pushing into a ridge of high pressure. Certainly the low to the west is coming up quick because Grant Dalton mentioned it in a dispatch to race headquarters yesterday - he was keen to stay to the north of the low and south of the high. A bit of tight-rope walking in the deep south!
Five day pressure forecast for the
Southern Ocean Image courtesy of COLA. What are we looking at here? Africa is at the top, South America to the west, the Australian Bight to the east, Antarctica in the centre. The Kerguelen Islands - passed by Club Med yesterday morning, and looming before Innovation Explorer today, are about half-way between Cape Town and Perth. Watch carefully the sequence, with its first and last images showing for twice as long as the middle frames. Well, If you believe the COLA model, and if you trust it all the way out to 120 hours, there appears to be no problem with blocked highs for Grant Dalton, Club Med and crew. This model shows a deep high pressure cell emerging below Tasmania and moving east past New Zealand over three days beginning tomorrow. Models are most accurate early in the piece, and looking at the upper level charts above, we can expect that elongated high - a characteristic shape when blocked in position - to form within the next 24 hours. But it really appears that the whole system will move to the east well ahead of Club Med, and if the model is to be trusted, the leading boats in The Race will have westerly flow all the way under Australia and into the southern Tasman Sea. What happens on the approach to Cook Strait, New Zealand, will be interesting because the boats will have to track well more than 10 degrees north - to 40 degrees south - to negotiate this gap between the north and south island of New Zealand. Winds south of Cape Town for January 26 Image courtesy University of Cape Town This wind charts shows those south-easterlies affecting South Africa, and the blob of high pressure to the south - these are the winds facing Team Adventure as they re-start The Race from Cape Town. It also shows a low swirling clockwise west of South Africa which Team Legato is hoping to use to sail south quickly and avoid further entrapment in the South Atlantic High. More great reading: Catch up on all the past action in our race archive. Here it from the horse's mouth at race headquarters. Follow the action between the world's toughest solo skippers in the Vendee Globe. Re-live the Sydney to Hobart yacht race! Break ice in the Ross Sea! Life on board Innovation Explorer,
January 23. heating system is now run for about 3 hours a day, at least to dry up the inside of the hulls where humidity otherwise seems well over 100%. "Helmsman Yves Loday is finally getting a taste of the big waves he We have to remember there are no breaks to stop her, so it is really important that the helmsman concentrates on catching the wave correctly and going fast without breaking. If the wave gets you from the side, then it's the wave that takes over and the helmsman loses steering power. Even though the waves are non yet quite perfect , there are no Read Skip Novak's account the following day! Besides being a very funny man, he tells us how his boat dived too far south and appears to be caught in weak low pressure between deeper low pressure cells .... Grant Dalton tells of his worries threading the needle between high and low pressure ...
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