Summary Box: Retailers post solid sales in July

JULY GAINS: Retailers reported a 4.6 percent gain in revenue at stores open at least a year, according to a trade group.

BEHIND THE TREND: Heavy discounts and high temperatures helped drive shoppers into the air-conditioned malls.

WHAT'S NEXT: Analysts, worried about a faltering economy, are concerned that the momentum won't continue in August and September when the bulk of the back-to-school shopping is done.