On 5 October, she escorted into New York and joined the screen for for nine days of exercises in shore bombardment and other drills before joining convoy UGS-21 which sailed from Norfolk, bound for North Africa. "Thompson" served as an escort, keeping ships in the channel as they plodded out to sea and prodding them to close up and keep in formation, while her echo-ranging gear was alert for prowling submarines off Chesapeake Bay. One day out, 16 October, (UGS.21 sailed from Hampton Roads on 5 November, and therefore I believe this to be 6 November) the wind and sea rose, presaging a heavy storm which served to scatter parts of the convoy and cause "Thompson" to note in her log numerous times, "telling stragglers to close up." After the transatlantic voyage, "Thompson" was released from escort duty on 31 October, to proceed to Casablanca, French Morocco.