Following the German invasion of Norway in April 1940 Storhaug participated in the defence of Norway as a soldier. He fought against the Germans in Solør on 18 April, and later took part in skirmishes at Dovre. In December 1940 he traveled from Ålesund to Scotland, where he joined the Norwegian Independent Company 1 (). He took part in Operation Anklet, the Commando raid on Reine on 26 December 1941.