Islands in the stream
10:00, 28 January 2003
by Tim Hedges

After several days of relatively straightforward sailing in the steady trade winds, the last 24 hours have seen quite a change as the wind has eased and become much more variable, gusting between 5 knots and 30. This has kept the crews busy and the skippers awake as they battle to ensure they always have the right sail up for the conditions. With daily runs around the 200 mark no one seems to have suffered too badly and they have all made some gains on race leaders Jersey.

At 0400 this morning duty skipper Richard Butler reported winds of 17 knots from the east north east, whilst 240 miles to the west skipper Sam Fuller on New York reported 15 knots so for the moment things have settled. Given the time difference between the boats and the UK our morning is their evening and Richard has noticed a marked diurnal effect, writing “(the wind) appears to be picking up for the evening as usual. Last night clouds died away to give a pleasant sunny day.” But ahead the airflow remains disturbed and we could well see some position changes in the next couple of days.

One of the reasons for this “disturbance” is the fact that the islands currently mark the divide between two different weather systems, the high pressure to the north east that has been driving the trades has drifted slightly south, a high pressure ridge just to the west of the islands and a low pressure system creating an anti-clockwise westerly air steam to the north east of the islands. Added to this is the position of the Hawaiian Islands themselves situated as they are in the middle of an ocean trade wind belt. Like rocks in a stream they literally cause eddies in the airflow and this turbulence then affects the winds. Mostly this is downwind (west) of the islands but as the westernmost boats are now only around 300 miles east of The Big Island, Hawaii itself, they will soon sail into these “local” conditions. To get to the finish the boats will have to sail west through one of the island channels and into the lee of Oahu. Whilst they could have chosen any route through it seems as if they are all taking the conservative(and probably sensible) option of remaining to the east until the last minute, then ducking through the Kaiwai channel between Ohau and Molokai. That said, Bristol has made a marked move to the west over the past day and will definitely be worth watching. They have obviously decided that at present there is little to be gained by just following Jersey.

Source: Official Site