The cold front passed over the fleet Thursday night (UTC), and the wind has shifted to the southwest. Suddenly, it's much colder, windier, and the seas are rapidly building. It's the Southern Ocean.
"It's the worst conditions in the South," said Jack Bouttell, on Dongfeng Race Team. "It's cold water, dark nights, windier, the air is heavier so it feels windier and you're a long way from anywhere if something goes wrong.
"Everyone is in a slightly different mindset in the manoeuvres in the South because it is much more dangerous. The driver has to take as little waves as possible but it's not nice..."
Dongfeng Race Team has surged into the lead overnight, perhaps by virtue of doing less of those manoeuvres. They have gybed just twice to MAPFRE's five times as the teams skirt the southern Ice Exclusion Zone.
The cold front allowed the fleet to compress somewhat, with just 20 miles between the top six boats. With the bulk of the fleet this close, the rankings can be expected to jump around over the next days depending on what gybe each team is on at the time of the position report.
"Whilst the front that passed through last night was relatively tame it marks the beginning of series of troughs and low-pressure systems that will propel us to the Horn," writes navigator Simon Fisher, from Vestas 11th Hour Racing.
"The strong westerly winds are creeping their way north as we speak and in the coming days we will find tough conditions, big seas and plenty of gybing down the invisible Ice limit as we aim to minimise distance and stay in favourable winds."
As the boats approach Cape Horn, the Ice Exclusion Zone has been pushed further south, allowing more options for when the teams approach with a forecast for strong conditions. The news has been well received.
"We have received the news that there is a change to the ice exclusion zone ahead and this has given us some options with the big weather we are expecting to see in about four days. Good news," writes Dee Caffari.
But before then, there are some big mileage days ahead, as the Southern Ocean lives up to its billing.