The last four ships of the class, starting with Oakland, had a slightly revised armament with a reduced main gun battery - the waist turrets being deleted - as they were further optimized for anti-aircraft fire in light of war experience.

By late 1942 these troublesome and relatively ineffective weapons began to be replaced in the surviving ships by twin mountings for the new and far superior Bofors 40 mm anti-aircraft guns with Mk 51 directors.

Also from early 1942, close-range AA armament was augmented by eight 20 mm rapid-fire anti-aircraft cannons in single Mk 4 mountings disposed two on the forward superstructure, four amidships between the funnels (displacing some of the ship's boats) and two on the quarterdeck aft.

The second quartet of the Atlanta class, sometimes known as the Oakland class, was commissioned with only six twin 5-inch/38 mounts and with Bofors guns from the start, with four additional twin Bofors 40 mm mounts compared to their predecessors: two displacing the former 5-inch/38 wing turrets (improving both stability and close-range AA firepower while easing congestion) and two between the funnels displacing the previous two pairs of 20 mm Oerlikons.

Although ships of this class were planned as destroyer flotilla leaders, the original design did not include anti-submarine armament such as sonar or a depth charge battery.

In early 1942, along with anti-aircraft and radar upgrades, these ships were fitted with sonar and the standard destroyer battery of six depth charge projectors and two stern mounted tracks.

The class was powered by four 665 psi boilers, connected to two geared steam turbines producing 75,000 horsepower (56,000 kW), and the ships could maintain a top speed of 33.6 knots (62.2 km/h; 38.7 mph).

Throughout World War II and the postwar years, they had problems with topside weight; this was addressed by a redesign of the class which was then constructed as the three Juneau-class cruisers.

Atlanta was scuttled after receiving a torpedo hit and heavy gunfire damage from Japanese surface warships and USS San Francisco on 13 November 1942 during the Naval Battle of Guadalcanal.

Reno was torpedoed off Leyte on 4 November 1944 resulting in a large fire and significant flooding, but was saved from sinking by the damage control efforts of the crew.