The International Council of Shopping Centers said sales were flat in the week ending Saturday but were up 3.6 percent from last year.
The trade group said weather's influence on shopping was "neutral." Weather Trends International said "warmer trends in the northern half of the United States slightly outweighed cooler trends in the South."
Potentially helping retailers, the price of gasoline dropped 3.9 cents in the week to $3.533 per gallon June 18. That adds up to a 40.8 cent drop in the average national price of gasoline in the past 11 weeks.
Less money spent on gasoline is that much more in discretionary funds that shoppers can spend.
Susan Sarandon 'very excited' about daughter's pregnancy
Jessica Simpson shares three-way kiss with friends in photo