until 23 January 1942. 1942 After escorting a convoy to San Francisco and back, Southard resumed patrols in Hawaiian waters on 15 February 1942. On 20 May 1942, she again left Pearl Harbor in the screen of an eastbound convoy. The ships reached San Francisco on the 31 May 1942, and Southard spent the next 10 days undergoing limited repairs in the Mare Island Navy Yard. She returned to Pearl Harbor on 1 July 1942. On 10 July 1942, she stood out for the South Pacific. Stopping along the way at both British Samoa and American Samoa, Southard arrived at Tongatapu, Tonga, on 22 July 1942. She departed on 25 July 1942, stopped at Efate Island in the New Hebrides, and made Guadalcanal by 7 August 1942, the first day of the Guadalcanal campaign. Southard participated in the opening bombardment of Florida Island, then joined the minesweeping force in a sweep to the south of Gavutu Island and through Lengo Channel. On 8 August, about 20 Japanese high-altitude bombers attacked the transport area, and Southard succeeded in shooting down at least one Japanese plane. When the beachhead on Guadalcanal had been successfully established, Southard settled down to a routine of screening convoys from New Caledonia and the New Hebrides to the Solomon Islands. For almost eight months, she steamed back and forth between Espiritu Santo, Efate, Nouméa, Tulagi, Purvis Bay, and Guadalcanal. There were frequent Japanese air attacks, and Japanese submarines prowled the sea lanes. Early on the morning of 10 November 1942, while passing between San Cristobal and Guadalcanal en route to Aola Bay on Guadalcanal, Southard encountered the Japanese submarine I-172 operating on the surface. She immediately slowed to and opened fire. I-172 submerged, and Southard commenced her first depth-charge attack. Southard lost contact with I-172 and did not regain it again until 06:07, almost three and one-half hours later. Over the next three hours Southard made five more depth-charge runs. After the last barrage, she sighted oil on the surface. She moved in to investigate. Upon reaching the oil slick, Southards crew could find no further evidence of damage, and she steamed on through the slick. When she reached a point about on the other side of the slick, the submarine surfaced almost vertically, exposing her whole conning tower, her hull forward of the tower, and part of her keel. Then the bow dropped about 10 degrees,