U.S. retail sales rose modestly in May as discount retailers Thursday reported growth even as unusually cool weather in parts of the country slowed spending on seasonal goods, while some teen-oriented retailers posted soaring gains.

Some luxury chains also blew past Wall Street expectations, as the market for high-end merchandise continues to boom.

"Growth for these retailers indicates that despite weather that was not particularly consumer friendly and the fact that gas prices have been going through the ceiling, well-presented stores can overcome these obstacles," said Kurt Barnard, head of consultants Retail Forecasting Group (search).

Analysts had widely predicted anemic sales as chilly weather in parts of the United States hurt demand for summer clothing and pool and gardening gear, while soaring gasoline left less money for discretionary items.

Wal-Mart Stores Inc (WMT), the world's biggest retailer, posted a 2.5 percent increase in May sales at stores open at least one year, a key measure known as same-store sales, as demand for groceries made up for sluggish sales of summer merchandise.

Wal-Mart forecast its June U.S. same-store sales would grow by 2 percent to 4 percent.

Costco Wholesale Corp.'s (COST) total May same-store sales climbed 5 percent, but it said cool weather slowed sales of seasonal merchandise and apparel.

BJ's Wholesale Club (BJ) posted only a 0.5 percent increase in May same-store sales, and company President and Chief Executive Mike Wedge said cold, wet weather throughout the month hurt sales in more than half the chain.

But Wedge said he was "encouraged by the fact that most of the summer sales season is still ahead of us and a break in the weather could release pent up demand."

No. 2 discount chain Target Corp (TGT) posted a 5.1 percent jump in May same-store sales, ahead of estimates, and forecast a June sales increase of 4 percent to 6 percent.

Department store operator J.C. Penney (JCP) posted better-than-expected May same-store sales of 3.5 percent, above analysts' estimate of 1.9 percent.

On the other end of the price spectrum, luxury retailers such as upscale department store Nordstrom Inc reported its May same-store sales rose 7.4 percent.

Another high-end department store, Neiman Marcus Group (NMG.A), Wednesday posted an 11 percent jump in May sales, well above Wall Street's expectation of a 5 percent increase. It cited fewer markdowns and strong sales of jewelry, handbags and accessories.

Some apparel retailers struggled in May.

Gap Inc.'s (GPS) May same-store sales fell 8 percent, and the company said it sees significant pressure on merchandise margins until late July and August. AnnTaylor Stores said its May sales fell 7.1 percent, citing cool and wet weather.

Limited Brands Inc (LTD), whose chains include its namesake clothing stores as well as Victoria's Secret and Bath & Body Works, reported a 1 percent drop in May same-store sales, compared with analysts' expectations for a 2.5 percent decline, according to a Reuters survey.

Some teen-oriented retailers, a group which has been in the spotlight, continued to shine. Wet Seal Inc.'s May same-store sales were up 56.9 percent and Bebe Stores Inc. rose 40.3 percent.

Shares of Wet Seal jumped 8.6 percent to $4.56 in pre-market trade on the Inet electronic brokerage, up from a close on Wednesday of $4.20 on Nasdaq. Shares of Bebe soared 10.8 percent to $43.13 on Inet, up from a Wednesday close of $38.94 on Nasdaq. Bebe shares marked their highest level since the company went public in June 1998.

American Eagle Outfitters Inc (AEOS) posted a same-store sales increase of 17.1 percent on Wednesday and backed its second-quarter outlook. Aeropostale Inc. on Wednesday said its May sales fell 4.9 percent, better than analysts' estimate of an 8 percent slide.

"We did see some strong sales coming from the teen retailers, but people are still concerned about the supposed denim glut and how that will impact back-to-school sales," said Michael Koskuba, an analyst with Victory Newbridge Capital Management.

Pier 1 Imports Inc. (PIR), which has faced stiff competition from discounters, posted a 7.7 percent slump in May same-store sales, on weak sales of outdoor furniture and garden accessories. It also lowered its outlook for first-quarter earnings.