After the latter was evacuated by the Japanese, she conducted escort of convoy operations in the northern Pacific. In August 1943 she proceeded to the Mare Island Navy Yard for an overhaul to her machinery and alterations. Louisville was in overhaul at Mare Island from 8 October until 24 December 1943. Like her sister ships her forward mast was cut down and her aft mainmast was removed and replaced with a lighter tripod just aft of the second funnel. "Louisville" had the camouflage measure 32-6D paint scheme added and two new mark 34 main battery directors installed. The 1.1 in AA cannon mounts were removed and replaced with several quad 40 mm Bofors mounts along with numerous 20 mm cannon. Improved radars and flagship spaces were also added. Following this work in January 1944, "Louisville" returned to the southern Pacific as the flagship of Rear Admiral J. B. Oldendorf, who was to command the naval gunfire support groups through the amphibious operations ahead. In the Marshalls at the end of the month, she bombarded Wotje Atoll, west of Kwajalein, on 29 January. Then the cruiser turned her guns on the airfield and troop concentrations on Roi and Namur on the southern tip of the atoll, contributing to the conquest of those islands by 3 February. During this campaign, while waiting bombardment further targets an 8-inch 55 caliber shell fired from ricocheted off the island to explode a near miss alongside "Louisville" starboard side causing heavy pieces of shrapnel which damaged the chiefs quarters, pierced the bulkhead, and turret No. 3 – 8-inch gun had shrapnel damage on the tips of the barrels- no injuries. Two weeks later, "Louisville" led the gunfire support group into action at Eniwetok.