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Volvo Ocean Race Weather links for the Southern Ocean Routing notes for Leg Two Volvo Ocean Race contents page Leg two updates: December 7: Illbruck charges to victory in leg two November 28: Race restart as fleet rounds Eclipse Island and enters the Great Australian Bight November 19: Clean reaching past Kerguelen as a cold front looms up from behind November 15: High pressure creates calm in the roaring 40s November 10: Upwind start from Cape Town Image © News Ltd News Corp heads for the Sydney Opera House and the finish at Sydney, 23 days after leaving Cape Town. December 7, 2001 Illbruck - the yacht that almost returned to Cape Town with a flooded bow section - sailed past the Sydney Opera House one hour ahead of SEB to take first place for leg two. Considering their win in leg one, this well-prepared outfit can claim a solid leadership in the Volvo Ocean Race. After leading the fleet right across the Australian Bight, SEB broached badly in Bass strait, destroying her largest masthead spinnaker and tangled the rudder with a sheet. Illbruck, in close second, took advantage of the drama, captured the lead and never looked back. Within two hours News Corp crossed the finish line, followed by Djuice Dragons, Amer Sports One, Assa Abloy and finally - four days behind - the girls aboard Amer Sports Too. Considering the fleet virtually restarted at Eclipse Island, it is interesting to see why they finished as they did. Fleet positions half-way
across Image © Virtual Spectator/Volvo Ocean Race Note the four weather features dictating winds in the Bight: low pressure north and south, high pressure east and west. Most of the fleet is struggling to stay in south-west winds circulating around the top of low pressure south of Tasmania. Amer Sports Too is positioned well north - they are the other red dot east of Eclipse Island - battling headwinds circulating around the bottom of low pressure over Western Australia. In both cases, a ridge of high pressure in the Bight is helping to compress the isobars. South again in search of better winds Illbruck and SEB dove south after rounding Eclipse chasing stronger winds as low pressure moved south over Western Australia and high pressure moved in from the Indian Ocean. Working with this synoptic duo was a low, developing south-east of the fleet and another high in the Tasman Sea. These four systems remained linked while the fleet sailed across the bight towards Bass Strait - but they didn't quite develop like the AVN model predicted. Let's remember that these mathematical models are remarkable achievements - they measure everything weather in 50 square km 'pixels' and extrapolate out to three and a half days, in the case of the AVN model and a week in the case of the MRF. They are incredibly accurate - more often than not a weather system will appear just as predicted. But these models are not so accurate that they can forecast the absolute shape of a weather system. And this is where ocean racing yachts come unstuck. The leading navigators rounding Eclipse Island watched their glowing screens and predicted with confidence that winds circulating counter-clockwise around high pressure to the west would veer to the south-west and build, driving the fleet across Bass Strait perhaps at record pace. News Corp trimmer and sailmaker Alby Pratt, put his faith in the models. "The weather looks good for a fast run into Bass Strait after we get clear of Eclipse Island," he said. "Everyone is hoping for some more spinnaker work and maybe a chance to regain the 24-hour run record, which we held earlier in the leg." Kevlar sailing, as SEB skipper Gurra Krantz likes to call blast reaching, did happen - but not to the extent that the fleet expected. In fact, the trip across the Bight was a race against encroaching light airs. In another example, News Corp elected to remain further north than Illbruck and SEB, hoping to stay closer to the rhumb line and save miles. Skipper Ross Fields explains: "I decided to cut the corner. There was an opportunity to make a good gain, but the weather model we had was slightly out and now we're losing miles. It was a worthwhile gamble that didn't pay off." In fact, the synoptic situation was 90 per cent as the models predicted. But the speed of that Western Australia low, the exact track of the developing low in the Bight, the exact shape of high pressure in the west - these factors differed slightly. Ocean navigators always try to predict weather at the ultimate local level. But, as this race has shown over and over again, conservative sailing will pay dividends when a synoptic situation is not cut-and-dried. What really did happen? Low pressure in the bight tracked south east as low pressure over Western Australia deepened. Critically, a ridge of high pressure moving across the Bight from the west filled in more quickly than predicted catching boats in the north in lighter airs than those in the south. Of course, the girls aboard Amer Sports Too found themselves close reaching in too much wind after they rounded Eclipse Island and ran into gradient pressure between a low over Western Australia and the building ridge of high pressure squeezing east from the Indian Ocean. The girls remained in the far north, in upwind conditions, all the way to Bass Strait, afraid of calms to their south. Illbruck and SEB stayed in favourable winds until their very approach to the Strait, when they became trapped in a 'col' - the windless zone between all four synoptic systems: low pressure north and south, high pressure east and west. The rest of the fleet followed just to the north of the leaders. The next critical junction was Bass Strait. Again, the models predicted low pressure - including portions of the same low which taunted the girls in the Bight - to enter the Tasman somewhere north of Montegue Island, on the south coast of NSW. Exactly where, and what its exact shape would be were beyond the scope of these incredible prediction machines. Multiple lows create problems for the models, and in this case the track and the shape of this new Tasman low would depend largely on how fast the low south of Tasmania dropped into the Southern Ocean and how a wet season 'monsoonal' trough over Central Australia would develop. Bad call for Assa Abloy Assa Abloy keen to improve her placing, risked sailing north of King Island. the rest of the fleet approached Bass Strait to the south of this island. As winds filled in from the east, it became clear that those who approached Bass Straits from the south held the upwind advantage. Assa Abloy would have to tack before she reached the Victorian shores, heading due south while the rest of the leading fleet maintained a course for Wilsons Promontory, and Gabo Island beyond, before heading north to Sydney. As the low entered the Tasman and deepened, it created a cold front to its north and west. Hot, humid conditions over the NSW coast and cool, moist air from the Southern Ocean converged over the Blue Mountains to create the wildest thunderstorm Sydney has seen this year. One record gust measured 170 kph at Richmond, west of Sydney. Damage created by the storm killed two girls pursuing their Duke of Edinburgh award in the city's west. A tree fell on their tent as they lay in their sleeping bags. Roofs and whole buildings were damaged as winds and hail swept through Sydney and Newcastle. South of the low, south-east winds deepened as winds circulated clock-wise around this system. Illbruck and SEB arrived in Sydney Harbour under moderate reaching conditions but by the time Djuice and Amer Sports One arrived, winds were in the 30 knot range and building. Amer Sports One raised its masthead kite to put on a show and before the nation's media performed a spectacular broach just outside South Sydney Head! The next leg starts on Boxing day, with a fleet of 80 yachts competing in the Sydney to Hobart. See you there! Fleet location map, Image courtesy of Virtual Spectator/Volvo Ocean Race While the fleet leaders sailed south of King Island on their approach to Bass Strait, Assa Abloy went north - risking an ordinary placing in the hopes of making a gain. But winds went east, veering south-east as low pressure moved out into the Tasman Sea. Those boats in the south were able to sail straight for Gabo Island and the NSW coast. Assa Abloy, on the other hand, had to tack away from the Victorian coast in order to get through the strait, and as a result finished sixth - ahead of Amer Sports Too by several days and Tyco, which returned to South Africa with rudder problems. Windless ridge prior to Eclipse Island waypoint creates a restart November 28, 2001 After 16 days of intense ocean racing the Volvo fleet rounded the West Australian waypoint of Eclipse island as if it was just another harbour bouy. SEB, Illbruck, Assa Abloy and News Corp all rounded the rocky outcrop within three hours of each other on November 27. Assa Abloy and News Corp were just 15 minutes apart. All but Amer Sports Too rounded the same day. Will the close racing last? Few pundits reckon the fleet will be this tight after Bass Strait. Like the island of Trindade, way back in the South Atlantic, there is a great chance that the fleet will split here, some risking it in the north and most heading south, seeking consistent breeze as high pressure moves slowly in from the west. Today, in the heart of the Bight, a weak trough from the north will try to interact with a weak front in the south , eventually developing into a low well south of the fleet. The two systems will work together to create 20-30 knots of wind from the south-east south of Eclipse Island , veering to south-west closer to Bass Strait until later in the week (November 30). For the Volvo fleet, this means serious blast reaching across the Bight with crews driving as hard as they dare to keep up with the weather system. Fortunately, the high behind them is elongating deeply north and south - a classic blocking pattern - and this system will move over the race course more slowly than usual, allowing the fleet to keep up with it for longer. Medium range Forecast models (MRF) show this high to slowly move towards Tasmania, extending a ridge into Bass Strait by the weekend - December 1-2 - and promising to slow things up again. By early next week - December 3-4 - this same high is forecast to slide south over Tasmania bringing south-east winds to the NSW coast as the Volvo fleet approaches Sydney. Surface pressure forecast Image courtesy of University of Wellington, NZ In the first frame of this animation you can see light airs - wide spacing between the isobars - south of Western Australia. This is caused by a ridge of high pressure - connecting high pressure cells west of Australia and another in the Great Australian Bight. Separating the two cells is a weak trough of low pressure reacting with an emerging low due south of Cape Leeuwin. This low forms deepens as it moves east, towards Tasmania, working with the elongating high in the west to create plenty of wind from the south throughout the Bight. The Volvo fleet should be able to blast reach towards Bass Strait as this system evolves, increasing speeds as winds veer to the south-west. Longer range models then show the elongated high moving in from the west to extend a ridge right through Bass Straight by December 1-2 before moving over Tasmania and directing south-east winds onto the NSW South Coast. Memories of a glassy ocean Wind is something all the crews are looking forward to, after spending 24-36 hours becalmed in a ridge of high pressure on their approach to Western Australia. The leaders saw those behind catch up fast and at one point recorded zero boat speed - a difficult feat on these sailing greyhounds. Race navigation commentator Mike Broughton described the Volvo 60 class as sensitive to light air: "The difference of just two knots of wind speed in conditions below nine knots, makes a significant difference to the boat speed of these yachts," he said. "Two knots of extra wind can give a speed differential of 25 percent extra boat speed when the winds are light. As the wind increases, this differential reduces to the point that two knots extra wind, at say 20 knots, only equates to about a 2 percent boat speed differential because the boat is 'fully powered up' (in flat water)." Assa Abloy co-skipper and navigator Mark Rudiger described his frustration at the time: "Right now we're certainly not on a high. In fact it's downright depressing. After several days of good racing and pushing the front, we are now drifting around watching all the other boats including Amer Sports One and Amer Sports Too make up big deficits. They see where the leaders park up, pick a slightly different lane, and throw the dice." Roaring north out of the Southern ocean That cold front which Rudiger recalled had developed over Kerguelen island and propelled the Volvo fleet towards Australia at a great rate of knots. After News Corp broke the 24 hour record for the Volvo 60 class, SEB took the title, sailing 460.1 miles on November 20, averaging18.89 knots. Skipper Gurra Kratnz described the atmosphere onboard as electric during the record run: "When Matthew Humphries was steering I stuck my head up in the companionway and just yelled at him, go, go, go. And then I saw the reaction. He was so fired up already that he started to scream and just furiously bullied the boat through the waves, jumping up and down at the wheel, almost jumping outside the boat as we were thrown from side to side in the waves. In the absolute inferno of wind and waves that followed I could only hear the boys under the cascades of water. Shouting, pushing and just going wild. Top speed? 34.79 on the dial." For day after day, winds remained cold and strong - always above 25 knots - backing from North-west to west to south-west as the front moved ahead of the fleet. For Amer Sports One crewman, Keith Kilpatrick, the bumpy ride couldn't have come at a worse time. Struck down with severe stomach cramps, he was confined to his bunk on a diet of saline fluids, anti-biotics and morphine as Skipper Grant Dalton radioed for a medicine airdrop courtesy of the Royal Australian airforce. These boys and their Orion aircraft have gained a lot of Southern Ocean flying experience thanks to the Vendee, Around Alone and BOC global challenges, so a simple heli-box drop was an almost routine operation. fortunately navigator Roger Nilson is a qualified doctor - the only one in the fleet -. As the fleet were dumped, one after the other, into that ridge of high pressure, sailing ended and drifting began. By the time land was sighted Californian Kilpatrick had improved markedly and just before Eclipse island he was transferred off the boat. Finally, Team Tyco will ship their boat from Port Elizabeth to Sydney with the yacht expected to arrive on December 12, in time for the December 26 restart to Hobart and onwards to Auckland. Surface pressure east of Kerguelen
Island Image courtesy of University of Wellington, NZ Kerguelen Island is in the lower left corner of this animation. The rhumb line to Eclipse Island crosses the image from the lower left to the upper right. Look at the intense low developing over the rhumb line, directing a bitter band of easterly winds back towards ocean dominated by winds from the northwest. Add to this a dominant westerly swell and you can imagine that the sea state around Kerguelen would be frickin' frightful! If the Volvo fleet was just a few days behind, they would have experienced one of the worst storms for years. It's all a matter of timing, isn't it? What if ... ? Take a look at the forecast charts for the Southern Ocean between Kerguelen and Eclipse Island and consider what might have been, had the Volvo remained trapped in high pressure south of Africa . The chart above, developed using AVN model data, shows a tight low developing on the Kerguelen to Eclipse Rhumb line, directing 50 knots and more of easterly winds towards an area of ocean dominated by very strong northwest winds, creating a crazy sea state. Had the fleet been to the south-west of this low at the time it began its big spin-up, we may well have seen a survival situation. Sure, the Volvo fleet sailed smoothly through the Southern Ocean on this leg. They may have wallowed in high pressure soon after Cape Town and prior to Eclipse Island, but never forget for one moment that the Southern Ocean has decided to go soft! © Jamie Brown/weather-wise.com 2001 November 19,00gmt Image courtesy of NOAA A broad trough is seen here stretching from South Africa towards a low south of Kerguelen Island just as the Volvo fleet round this half-way point to its south. Models have been forecasting a low to develop out of this trough to the north of the Cape Town to Eclipse Island rhumb line, but as the forecast date draws closer, the low looks like fading. A cold front will instead develop out of this trough as the parent low, south of Kerguelen, deepens. This renewed front looks like providing plenty of power to get the fleet north towards Australia before high pressure moves in from the west. Clean reaching past Kerguelen as cold front looms up from behind November 19, 2001 That balloon of high pressure we talked about last update was anything but a burden to the Volvo fleet, positioned on the rhumb line and south of the high's centre. The 60 foot yachts initially caught south-west winds flowing behind a front, moving away to the east and rode these winds on a south-east heading to 50 degrees. There were icebergs aplenty in those early days - interestingly the greatest concentration was found just south of the African continent. During last year's Vendee Globe, solo sailors also reported the most icebergs south of Africa and no doubt the northbound Benguela current helps to bring these deadly bergs into reach of racing yachts. As the high to the north moved over the fleet, this synoptic system worked in tandem with low pressure south of 60 degrees to create powerful gradient wind flow up to 40 knots. First Djuice Dragons sailed more than 400 miles in 24 hours followed by News Corp which nailed a 24 hour record run for this class of yacht: 451.2 nautical miles, an average of 18.8 knots. This record is just 2.1 miles more than the previous record, set by Lawrie Smith's Silk Cut in the last Whitbread in this same ocean. It seemed only the other day that Ross Fields' team was wallowing in a windless ridge as the fleet drifted out of reach. Now the team with Bart Simpson as mascot looks ready to challenge for the lead. Interestingly, both News Corp and Djuice were positioned further south amongst stronger winds than the rest of the fleet. Ross Fields wrote an email to race HQ describing the thrill: "We're smoking.... sitting on 18 knots and surfing to 28 knots. Now we have a fractional spinnaker on, one reef in the main [sail] in 34 knots from the west. Everything, including the toothbrushes, is stacked down the back of the boat to keep the bow out of the water." Apart from squall clouds accelerating the wind locally, the synoptic situation was literally straight-forward. Winds flowed cleanly from the west allowing crews to drive their boats hard and fast ... and wet. Grant Dalton aboard Amer Sports One summed it up: ""Brother is it wet. It would be impossible for the boat to be any wetter. We bail it literally every two hours maximum and the water just pours over the deck." With the Crozet Islands behind them Kerguelen appeared over the eastern horizon, marking the half-way point between Cape Town and the west coast of Australia. At this point the wind veered to the west north-west as high pressure to the north slipped away to the east and the first real synoptic change loomed up from the west: A cold front developing out of a low pressure trough which promises to carry the fleet swiftly towards Eclipse Island and the Great Australian Bight. This front will provide the fleet with plenty of power to get north towards Australia before prevailing high pressure overtakes them from the west. Animated forecast isobars for
waters Image courtesy of NOAA This simple animation shows clearly how an approaching cold front affects wind flow in the Southern Ocean. First winds flow from the north-west as low pressure approaches from the south-west. As the front develops winds veer to the north before backing to the west again as the front passes. It is interesting to note that winds at the surface tend to veer right compared to the direction of the isobars and if you click on the credit link above and create an image showing both surface pressure and wind flags you will see this phenomenon clearly. Synoptic reflections For several days now the MRF (medium range forecast) model has been predicting a low to develop out of that trough we talked about last update. Surface wind charts show that low already developing south east of Africa, but it is now unlikely to affect the Volvo fleet at all. However, it is interesting to note how the models handled this weather system. Initially the low, forecast to deepen to about 987hpa, was shown to track north of the Cape Town to Eclipse Island rhumb line and threaten the fleet with northerly winds. But as the forecast dates drew nearer and the models become more refined, the low was predicted to track along and just to the south of the rhumb line before dispersing into a broad low pressure trough over Kerguelen. North towards Australia Now it seems the low will fade altogether, and a cold front will instead track eastwards allowing the fleet to sail ahead of it in NW wind flow towards Western Australia. As the front overtakes the fleet and winds back to to the west the Volvo yachts will maintain fast average speeds towards Eclipse Island. How far north they will sail before they lose touch totally with the front? It is too early to say, but one thing is certain: Unless the front proves to be a real whopper and brings south-west winds all the way to Australia, the feet will fall into lighter airs associated with high pressure moving in from the west. This will be the next challenge: Dealing with high prevailing high pressure in the Bight. Speaking of cold fronts: If Grant Dalton was sailing his Club Med maxi cat right now, there would be no question that he would stay ahead of this cold front as it pushes into clean ocean. After all, he did exactly this when he set an Indian Ocean crossing record during The Race. Back to port for Tyco What this scenario holds for Tyco? Even if low pressure forming out of the front fails to deepen, winds flowing into the trough from the south on its western flank should provide this sad, disabled yacht with an easy run back to Port Elizabeth for repairs to her rudder. At least something is going right for this disappointed crew! © Jamie Brown/weather-wise.com 2001 Forecast
wind and pressure chart Image courtesy of NOAA Not your typical Southern Ocean 'roaring 40s' synoptic situation, but then the Southern Ocean is not one to be pigeon-holed! This surface pressure and wind-strength chart shows the very centre of high pressure (1030mb) just to the north of the Volvo fleet at about 43 degrees south. You can just see the black outline of the South African coast in the upper left. The eight 60 foot yachts have sailed through headwinds and calms in the last four days. They could face a chance of getting stuck again unless they can sail south fast enough to stay in favourable south-west winds. High pressure in the roaring 40s! Can the Volvo crews work hard enough to sail south of this new high and stay in reaching conditions? November 15, 2001 Getting to the roaring westerly trade winds has been a frustrating battle for the Volvo fleet. Pounding into 35 knot south-easterlies soon after leaving Table Bay is not unusual, however. This corner of the globe is notorious for these winds, as a trough of low pressure camps over Africa and powerful high pressure takes up residence just to the south. Where these two pressure systems squash together, strong winds are created. The damage sustained by these headwinds in an area of ocean affected by converging currents - the northbound Benguela and south-bound Agulhas was bad indeed. Illbruck flooded her forward hold and her crew had a hectic moment keeping everything under control. Great way to enter the Southern Ocean, eh? And what about the light airs well south of Cape Town? Nothing unusual there either. If high pressure is helping to cause the strong gradient winds off the African coast, then there has to be a centre to this high further south. Newscorp discovered these light airs up close and personal after sailing south-west away from the fleet and the rhumb line expecting to clear the high pressure earlier than the others but that didn't happen. The ridge over the top of them ballooned out trapping them in light airs while the rest of the tight fleet, just 25 miles away, drifted out of reach. Hunting for clear air But surely you would imagine that once clear of this windless ridge, the yachts in the Volvo could expect to find clear westerly air ... Especially after they've crossed the 40th parallel. Wouldn't you? Well, the fleet has had a generous whiff of moderate south-westerlies flowing around the bottom of this high, but the big question now is whether they can get south fast enough and far enough to escape a new bubble of light winds coming from the west. Indeed, the introduction to downwind sailing southern style remains exciting. The Southern Ocean is cold down here and the blast of freezing water over the foredeck wakes everyone up. The wind is cold here too, and cold air equals dense air. It doesn't take much of it to get powered up on a reach! Currently the fleet is reaching in 20-25 knots of south-westerly flow and the decks are awash. Mark Rudiger, navigator aboard Assa Abloy summed it up: "I just went on deck to have a look, and it amazed me again how much the ocean has changed," he emailed race HQ. "It is now becoming frothing white and there are thousands of sea birds swarming everywhere. You can't tell who is who, because all you see are wide eyes peering out of identical foulies." Unfortunately for leading yacht Tyco, this latest pressure was enough to separate the rudder from its shaft, the damage no doubt created by rough upwind sailing after Cape Town, and may have started way back in the Bay of Biscay. Whatever the case, this sad ship headed back to South Africa, disappointed indeed. The focus for new fleet leader Assa Abloy, with Djuice Dragons right on their tail, is to negotiate the best course in light of this new high pressure bubble moving in from the west. What was a narrow ridge of high pressure squeezing eastward from the Atlantic was becoming a big, burgeoning balloon, with its effects stretching beyond 60 degrees south. Unless the leading yachts can stay south of the high's centre the perfect surfing will end and south-west winds will back to the south and begin to fade. It is unlikely that the fleet will become trapped under its fickle centre, they all seem to be moving too quickly away to the south-east riding winds flowing behind a cold front. But there is the chance that a few dozen miles north and south may make a big difference to wind speed in the next 48 hours. Approaching low pressure trough But that's not all: The AVN model shows the high moving quickly to the east, and by Saturday, November 17, the fleet will be reaching in northerlies predicted to build beyond 20 knots followed by more calm as a trough of low pressure or a weak cold front moves over the top of them. The longer-range MRF model shows a low forming out of this trough to the north of the fleet, bringing northerly winds on its eastern flank. Beam winds with a prevailing swell from behind. 84 hour forecast
(AVN) for waters
south of Africa Image courtesy of NOAA As high pressure moves away to the east, this trough of low pressure - a weak cold front attached to a low below 60 degrees south - will move over the fleet fro the west. While the AVN model is the best short-term forecast tool available, the chart above is at its extreme - 84 hours in advance - so we will wait and see the outcome. But from here it looks like more light winds as this trough interacts with low pressure over the African continent. After that? Well, the waters south of Madagascar are a known cyclogenesis region and we might see a low develop out of this trough which could further hamper the Volvo fleet with strong easterlies rotating clockwise around any developing low pressure. Those furthest south at this time could be worse off. Surface winds south of Cape Town Image courtesy of NOAA With low pressure over the African continent and high pressure in the Southern Ocean, a band of 30 knot plus winds were created over waters south of Cape Town as the Volvo fleet started Leg Two for Sydney. This gradient wind was right in the face of the yachts as they battled their way out of Table Bay and south towards clear westerly air. Of course, between the fleet - slamming into headwinds and lumpy seas - lay light winds at the centre of high pressure, seen here as small light blue barbs at the bottom of the chart. Stay tuned here and at the official Volvo web site. © Jamie Brown/weather-wise.com 2001 Image © Rick Tomlinson/Volvo Ocean Race Amer Sports Too slams to windward as stiff south-east winds greet the Volvo fleet on their exit from Table Bay. Upwind start from Cape Town South-east winds predicted as Volvo fleet dives south November 10, 2001 24 hours before the start from Cape Town, the synoptic situation is straight forward and simple. Massive elongated high pressure due south of Cape Town dominates the surface pressure chart. North of the cape a trough of persistent low pressure puts the squeeze on easterly air flow rotating anti-clockwise around the Southern Ocean High, compressing the isobars. The result? 35 knot easterlies on Table Bay. 400 miles south, on the other side of the high pressure bubble, a progressive flow of cold fronts and associated westerly winds offered a fast ride across the Indian Ocean. But the big tactical decision for the Volvo fleet will be getting to those westerlies first. The Great Circle route to Eclipse Island, off Albany Western Australia follows an arc south-east of Cape Town, through the Crozet Islands and nearly touching Kerguelen before curving north again. Sure, this may be the shortest route to the way-point of Eclipse Island, en route to Sydney, but in reality more wind to the south will force yachts away from the rhumb line. Considering the forecast for strong easterly winds to veer to the south-east and moderate - but only slightly - my guess is the fleet will sail due south, crossing the high at right angles and hit the westerly trades ASAP! Keep an eye on winds backing to the north-east, and north-west heralding an approaching cold front and quick descent into the Southern Ocean. However, if this big high pushes any approaching front south of the Volvo fleet, we may see a repeat of four years ago when the the yachts wallowed in absolutely windless conditions after leaving Cape Town. Even the wandering albatross failed to get enough wind under its wings! Keep an eye on Grant Dalton and Roger Nilson aboard Amer Sports One. They were the ones to head south after rounding Trindade because they knew better winds lived in that direction. Will they adopt the same strategy? Save room in your heart for Djuice Dragons, the real losers in the last leg thanks to gear failure, poor rationing and a boat not optimised for upwind or light wind sailing. While they will be at a disadvantage getting to the westerlies, once in the groove this boat should shine. Let’s hope they can pull off a top placing on this leg, after all Knut Frostad placed second on this leg last race aboard Innovation Kvaerner. Deserving winners of leg one, Illbruck, will also lay claim to the Sydney leg. As part of their training last year they shipped their training yacht, the ex-EF Language, to Fremantle and sailed to Auckland before returning to Sydney in time for the Hobart race. These boys have done their homework and deserve to win. © Jamie Brown/weather-wise.com 2001 Hot links for the Southern Ocean Forecast Models:Build you own forecast chart using NOAA's AVN model. You stipulate latitude and longitude and what variables you want, i.e. barometric pressure at the surface or at 500mb, temperature at different levels, wind strength etc. Build you own forecast chart using NOAA's MRF model. You stipulate latitude and longitude and what variables you want, i.e. barometric pressure at the surface or at 500mb, temperature at different levels, wind strength etc. South African surface pressure, wind and precipitation charts three days in advance using the MRF model thanks to University of Cape Town. Surface
pressure from the Australian East Coast west to Kerguelen 12 hour forecast of Surface pressure for the Southern Ocean and Tasman Sea compliments of Ocean Weather using the AVN model. 24, 48, 72, 96 hour forecast for the Southern Ocean using the MRF (Medium Range Forecast) model, compliments of the Institute of Global Environment and Science. 24, 48, 72, 96hour forecast for Wind and direction in both the north and south Atlantic, using the AVN model thanks to the ocean modelling branch of NOAA. Three to six day forecasts for the Southern Hemisphere courtesy of the European Centre for Medium Range Weather Forecasts Australian Pressure maps from surface to 200mb in six separate images thanks to the National Centers for Environmental Prediction (formerly the National Meteorological Center). All maps use the MRF model and are produced by the Institute of Global Environment and Science. Infra-red: The University of Nottingham offers geo-stationary satellite information showing the east Atlantic and Europe/Africa. Animated loop of current Australian infra-red images Current surface pressure South African synoptic chart including waters south to the Antarctic continent, east to Trindade and the Falklands and west to Amsterdam Island thanks to the South African Weather Service. Shipping forecasts thanks to the South African Weather Service. Australian surface pressure including four day forecast models using the Australian model thanks to the Australian Bureau of Meteorology. Southern Indian Ocean pressure with options for 12 hour forecast charts thanks to the Australian Bureau of Meteorology. Surface winds: Quickscat satellite derived winds for the
Southern Ocean: South African waters between 40 and 60 degrees south: Ascending and descending. Crozet Islands: Ascending and descending. Kerguelen Island: Ascending and descending. Waters south of Cape Leeuwin between 40 and 60 degrees south: Ascending and descending. Cape Leeuwin, Western Australia including Eclipse Island: Ascending and descending. Great Australian Bight including Bass Strait: Ascending and descending. South Tasman Sea: Ascending and descending. North Tasman Sea: Ascending and descending. Upper level winds: Southern Indian Ocean
00gmt, 0600gmt,
1200gmt
and 1800gmt Related upper level wind charts The Aviation Weather Centre offers these terrific flight level charts SIGWX) which show the position of jet streams over much of the globe (mostly Northern Hemisphere). Because upper level winds, like the jet stream, steer our weather systems, knowing where these winds are and how they are behaving helps us to understand whether systems are moving east to west quickly or whether they will stalling because of a kink in the pipe-line. Forecasts up to 18 hours in advance. Wind analysis from the University of Wisconsin showing surface, upper and jet stream - or water vapor - winds. As well, there are charts showing wind shear and upper level divergence. For the arm-chair sailor, the low-mid level infra-red winds tell an awful lot about the sea state where the boats are. Colour-coded arrows report wind strengths and direction at different levels. Remember: Friction at the surface slows the wind down a bit, so it will never be as strong at wave height as it shows on the 900hPa chart. More great reading: Get the good oil at the official Volvo web site. Read all about the Jacques Vabre trans-Atlantic race . Playstation smashes the trans-Atlantic record by 44 hours by surfing the perfect front! Battle of the Open 60s in the EDS Atlantic Challenge: Which route works best We analyse the Los Angles to Honolulu Transpac, 2001 Follow the Challenge Mondial Assistance through the official web site and get a preview of weather conditions on the route. Catch up on all the past action of the recent Vendee Globe in our race archive. Re-live the action between the world's fastest multihulls in The Race Re-live the 2000 Sydney to Hobart yacht race! Break ice in the Ross Sea! Re-live the solo trans-Atlantic race of June 2000 and the Quebec to St Malo of last August.
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