Great Britain secured two golds at the Sail for Gold regatta as Giles Scott won the Finn class while Luke Patience and Elliott Willis clinched the 470.
Scott, 26, has won 10 of 14 races in Weymouth and Portland - the third leg of the Champions Sailing Cup series.
"It's been good to get out there on home water and do some good quality racing," said Scott, who won the European title in May.
Lucy Macgregor and Andy Walsh have a nine-point lead in the Nacra 17 class.
Dave Evans and Ed Powys also go into the final day on Friday with an advantage, leading the 49er class by 15 points.