The Arctic Circle has finally arrived, and among the countless ways the fleet could have reached it, the crossing looked almost ironically like a club race: every boat in a line, close-hauled on starboard tack, cut the parallel in pretty much the same spot, before bearing away, hoisting the headsails and heading off on a reach, still on starboard.

"Allagrande Mapei" crossed the Arctic Circle live on video just before 8pm yesterday. In the extremely short Arctic night – at those latitudes in June, the hours of darkness disappear almost entirely – Ambrogio set off in pursuit of "Initiative Cœur" in a tight gybing duel off Iceland that now has him in third place, just in front of the French skipper and chasing second. The east coast of the island brings a marked acceleration in the wind, which the IMOCAs are using to begin the long descent south.

At the head of the fleet, "Macif" is crossing the connecting zone between the two low pressure systems sitting over the North Atlantic. This is a trough axis characterised by irregular wind and a weak gradient, where even minor differences in position can translate into significant changes in pressure and wind direction. For Ambrogio, attention is instead focused on the movement of that same low pressure system south of Iceland. Over the coming hours the system should shift eastward, opening a window of passage towards Ireland but also bringing demanding conditions, with "Allagrande Mapei" pushed at full power on a reach – her most favourable conditions. At this stage, the various options for the descent around the British Isles seem to be progressively converging, and the Atlantic route appears the most likely choice for the return towards milder latitudes.

Yesterday was also marked by news that deeply affected the sailing world and, in particular, the IMOCA fleet: the passing of Charlie Dalin. The news arrived just as his boat, now sailed by Goodchild, is leading this Vendée Arctique with authority. Ambrogio and the whole Allagrande Mapei team stand with his family and loved ones, paying tribute to one of the greatest sailors of his generation.