In May 1942 "Atherstone" transferred to the 16th Destroyer Flotilla, escorting convoys off the East coast of Britain. In March 1943 the ship transferred to the Mediterranean, joining the 18th Destroyer Flotilla. In July 1943, "Atherstone" took part in the Allied invasion of Sicily, forming part of the naval force supporting the landing of the British XXX Corps south-west of Syracuse. In September 1943, "Atherstone" took part in Operation Avalanche, the Anglo-American landings at Salerno in Italy, forming part of the escort for the providing air cover for the landings.