The 28-year-old Dane was the runner-up to reigning Olympic champion Marit Bouwmeester of The Netherlands on a day when thunderstorms and lightning delayed the start of racing for around four hours at the Australian city's Sandringham Yacht Club.

Victory puts her onto six points, giving her an advantage of one over nearest challenger Bouwmeester.

Overnight leader Maud Jayet of Switzerland finished sixth today in the yellow group and now sits in third place overall on nine points.

A further five points behind her in fourth spot is Belgium's Emma Plasschaert, who came third in the blue group today.

The yellow group race was won by Rio 2016 Olympic silver medallist Annalise Murphy of Ireland.

France's Pernelle Michon finished second, while The Netherlands' Maxime Jonker came third.

Two attempts were made to get the yellow group started shortly after 2pm local time, but a series of rolling thunderstorms and the accompanying lightning forced the sailors to hurry back to Sandringham Yacht Club before the course became dangerous.

There was a long wait onshore, but with the regatta already two races behind owing to light winds on the opening days, the answering pennant flag came down at 5pm and the sailors rushed to their boats.

The yellow group was eventually put into sequence at 5:55pm and got a clear start at 6pm. 

The blue group followed five minutes later.

Qualifying is due to continue continue tomorrow, with at least one race needed to complete the series.

The first discard comes into effect after four races, and that could shake up the leaderboard considerably.

The earliest sailors can be split into gold and silver fleets is Thursday (February 27), the penultimate day of the regatta.

If possible, three races will be sailed on each remaining day.