The fleet positions are very interesting now, and with the advent of relatively stable south east trade winds will lead to a fascinating few days. They are more or less lined up over 150 mile front lined up with the great circle route to Salvador. This means that the race will be decided in an 1,100 mile drag race to the finish. One thing high on the crews' minds will be the prevention of chafe and wear on the sails and the lines. Chafe is one of the major enemies on board a boat, and is to be avoided at all costs, in the lines, the sails, clothing and most importantly people. So even though the yachts will probably not be sailing under spinnaker, as the wind will be too coming from too far forward to allow these sails to fly, the mast men will still be going up the rigs at least once a day to check all the equipment for signs of wear. A large number of the mast men are actually mast ladies as given the option of hoisting an 80 kg lump or a 60 kg lady up the rig, most winch grinders will go for the latter! While they are up there, nearly 90 feet above sea level, the visible horizon increases greatly, so they will be keeping a sharp eye out for those tell tale white triangles of other yachts on the horizon.
There are several major factors which affect the last eleven hundred miles into Salvador. The wind is one, but current is another. Broadly speaking the South Equatorial Current is driven by the anti-clockwise rotation of air around the South Atlantic High. This body of water comes across the Atlantic, hits the continental shelf at the eastern tip of Brazil, and splits into two, one stream going along the north coast of Brazil, forming the Guyana current and eventually joining the Gulf Stream, and the second going down the eastern edge of Brazil past Salvador. This is the one that the yachts want to hook into. The strongest bit of this will tend to be at the edge of the continental shelf, approximately at the 200m depth contour, which is shown as the edge of the orange section on the illustration (courtesy of the US Navy). The problem is that there are many counter-currents and eddies just inside this, so by straying half a mile too close to the shore the current could go from two knots with to a knot against - an overall loss of three miles every hour.
The localized weather conditions due to the proximity of land will be important too, especially in the last few hundred miles. The huge South American land mass will be hotter than the sea in the day, but cool rapidly each night, and this will cause havoc with the steadiness of the wind closer inshore. All in all - an exciting few days ahead!