The International Council of Shopping Centers said sales rose 0.8 percent compared to the previous week and 3.6 percent compared to the same week of 2011.
Traffic at department stores, "perk[ed] up nicely relative to the same week of last year," the report said.
The trade group said unseasonably warm weather returned to the Northeast, the North Central and the West, which stood in contrast last year, when the third week of April was the coldest in 20 years.
With warm weather encouraging trips to stores, gasoline prices headed lower for the third consecutive week.
Gasoline prices averaged $3.87 per gallon on April 23, a drop of 5.2 cents from a week earlier, the Energy Information Administration said.