In March, she returned south to the area around Buna to prepare for operations to capture the remainder of the northern coast of New Guinea. During the Hollandia assault, the first of five leap frog steps to the Vogelkop, "Welles" was assigned to Task Group 77.2 (TG 77.2), the Central Attack Group which mounted its assault at Humboldt Bay on 22 April. About a month later, on 18 May, she supported the landings at Wakde Island and at Sarmi on the New Guinea mainland. From there, the warship continued with General Douglas MacArthur's amphibious jump to Biak Island where she provided gunfire support during the landings and consolidation operations from 27 May to 2 June. During that time, she destroyed several Japanese barges, harassed enemy ground forces, silenced a shore battery or two and helped to repel several air attacks.