"Wichita" departed Philadelphia after her commissioning, bound for Houston, Texas. She arrived on 20 April 1939 and took part in the dedicatory and memorial service at the San Jacinto Battle Monument and War Relic Museum. The ship left Houston on 1 May for her shakedown cruise, during which she visited the Virgin Islands, Cuba, and the Bahamas before she returned to Philadelphia for post-shakedown repairs. On 25 September, a few weeks after the outbreak of World War II in Europe, "Wichita" was assigned to Cruiser Division 7 in the Atlantic Squadron, based in the Hampton Roads. She conducted her first neutrality patrol on 4–9 October. After returning to port, she went into dock at the Norfolk Navy Yard for maintenance, which lasted until 1 December. On 4 December, "Wichita" steamed to Guantanamo Bay, Cuba, arriving on the 8th. There, Thomson assumed command of the newly formed Caribbean Patrol, which included "Wichita" and the cruiser , and the destroyers , , , , and , and Navy patrol squadrons VP-33 and VP-51. Over the course of the next three months, the force conducted a series of training maneuvers in the Caribbean. At the end of February, "Wichita" returned to Norfolk via Philadelphia, where she participated in further training through May.