He delivered news and radio and television documentaries for NRK and TV 2, and wrote for national outlets such as Dagbladet, Dagsavisen, Dagens Næringsliv, Morgenbladet, the Norwegian News Agency and Samtiden.
According to Dagsavisen commentator and former Labour Party politician Arne Strand, Nordahl was one of the three most powerful politicians in the Norwegian labour movement, and thus also in Norwegian 20th-century politics, together with Einar Gerhardsen and Martin Tranmæl.
He was an editor in Arbeiderbladet from 1952 to 1964 and 1968 to 1970, director of the International Press Institute from 1964 to 1968 and editor-in-chief of the Norwegian News Agency from 1970 to 1980.
Other celebrities from Siggerud include Christian Ingebrigtsen, who used to be in the boy band A1, Trude Mostue, well known in the UK as "Trude the Vet", TV host, actor and journalist, Christian Strand :no:Christian Strand (adoptive son of political editor in the newspaper Dagsavisen, Arne Strand :no:Arne Strand), plus various local celebrities, amongs other people including Christian's dad Stein Ingebrigtsen.