The International Council of Shopping Centers-Goldman Sachs weekly sales report said sales climbed 0.8 percent week to week and 1.9 percent compared to the same week a year earlier.
The trade group said it was a strong week for staples. Sales of basic items "seemed to perform best over the past week with notable improvement at grocery stores and discounters."
Business was weaker at a broad range of stores, including electronics, office supply, clothing, department stores and drug stores, the weekly consumer tracking survey found.
Weather Trends International Inc. said the week was slightly cooler than the same week of 2012.
Snow hit the Northern Plains and Rockies in the week, which not only keeps shoppers at home, but discourages sales of spring merchandise.
Meanwhile, gasoline prices dropped for the eighth consecutive week, the Energy Information Administration said.
In the latest week, gasoline prices shed 0.6 cents to an average Monday of $3.536 per gallon.