On 18 April, "Arkansas" departed for Northern Ireland, where she trained for shore bombardment duties, as she had been assigned to the shore bombardment force in support of Operation Overlord, the invasion of northern France. She was assigned to Group II, along with "Texas" and five destroyers. Her float plane artillery observer pilots were temporarily assigned to VOS-7 flying Spitfires from RNAS Lee-on-Solent (HMS Daedalus). On 3 June, she left her moorings, and on the morning of 6 June, took up a position about from Omaha Beach. At 05:52, the battleship's guns fired in anger for the first time in her career. She bombarded German positions around Omaha Beach until 13 June, when she was moved to support ground forces in Grandcamp les Bains. On 25 June, "Arkansas" bombarded Cherbourg, in support of the American attack on the port; German coastal guns straddled her several times, but scored no hits. Cherbourg fell to the Allies the next day, after which "Arkansas" returned to port, first in Weymouth, England, and then to Bangor, Wales, on 30 June.