"Greer" remained in the North Atlantic through 1941, shepherding convoys to and from MOMP, the mid-ocean meeting point at which American ships took over escort duties from the hard-pressed Royal Navy. After overhaul at Boston, she turned south 3 March 1942 to resume patrol duty in the Caribbean. In addition to regular escort duties, "Greer" performed many other tasks, including rescuing 39 victims of German U-boats. In May she stood guard off Pointe a Pitre, Guadeloupe, trying to keep the Vichy French government from getting to sea.