After her shakedown cruise along the East Coast and in Cuban waters, "Parker" served as a convoy escort to North Africa, participating in the attack on Mehedia and Port Lyautey 7 November 1942. Following her return to the Atlantic Coast, "Parker" escorted convoys to North African ports on five occasions. On the fourth, she supported the Sicilian invasion 5–13 July 1943. Convoy escort duty to the United Kingdom and the Mediterranean Sea followed. On 6 November, when 30 planes attacked her convoy, "Parker" shot fifteen down.