The International Council of Shopping Centers-Goldman Sachs weekly sales report said sales receipts for the week topped the same week of 2012 by 2.6 percent.
The trade group said the year-over-year gain was the strongest in nine weeks. Traffic at drug store and wholesale clubs improved "markedly" in the week, the report said.
Weather Trends International Inc. said the week's temperatures, on average, were "a hefty 4.7 degrees Fahrenheit colder than last year and 2.2 degrees below its long-term trend."
Meanwhile, gasoline prices dropped for the ninth consecutive week, the Energy Information Administration said.
In the latest week, gasoline prices shed 1.6 cents to an average Monday of $3.52 per gallon.