Following shakedown off Bermuda, "Melvin" sailed for the Pacific on 1 February 1944. Arriving Pearl Harbor on 4 March, she got underway for Majuro five days later and for the next month conducted antisubmarine patrols and participated in the blockade of enemy-held atolls in the Marshall Islands, returning to Pearl Harbor on 2 May. There, she underwent intensive fire support training and 31 May departed with Task Group 52.17 (TG 52.17) for Saipan. Approaching that island on the night of 13/14 June, she sank . A few hours later, while steaming off northern Saipan, she again attacked an enemy vessel, this time a merchantman, which burned brightly for a few hours before sinking. For the next 23 days, she provided counter-battery fire, conducted antisubmarine patrols, damaging an enemy submarine on the 17th, served as call fire ship for Marines on the beach, escorted ships from Eniwetok, and participated in the bombardment of Tinian.