On 2 April 1941, "Astoria" departed Pearl Harbor for the west coast of the United States. She reached Long Beach, California, on 8 April and entered the Mare Island Navy Yard on the 13th. During her refit, she received quadruple-mount /75 cal anti-aircraft guns and a pedestal fitted at her foremast in anticipation of the imminent installation of the new air-search radar. Emerging from the yard on 11 July 1941, the heavy cruiser sailed for Long Beach on the 16th. Later shifting to San Pedro, "Astoria" sailed for Pearl Harbor on 24 July 1941.