FEBRUARY SALES MARK CHANGE AMONG SHOPPERS.

Byline: Jennifer Steinhauer The New York Times

Underscoring a principal shift in the way Americans now shop - that is, when they feel like it, not simply when merchants want them to - retailers on Thursday reported strong sales for February, usually a quiet shopping month.

Higher-than-normal temperatures and stores bursting with fresh spring merchandise combined to bring shoppers out of their homes and into stores in spite of the effects of El Nino, which hammered California with storms during much of the month.

The Goldman Sachs same-store index, which measures major retailers' sales in stores open at least one year, rose 5.9 percent last month, above the 3.8 percent rise in February 1997 and the highest increase for the month since 1994.

These sales figures are interesting less for what they say about the individual retail companies but rather for what they remind retailers about how people have changed their shopping patterns in recent years.

It used to be that retailers set their calendars and expected consumers to follow them - when clam-digger pants came into stores in March, consumers were expected to buy them even if it was 3 degrees outside, and when Christmas approached, they were thought to do a great deal of their shopping the weekend after Thanksgiving.

But in recent years, retailers have been vexed that shoppers have shown tendencies to buy closer to need - gifts for Grandma an hour before the stores close Christmas Eve, back-to-school shoes for Junior when his feet grow and not because he is going back to school.

Though December, for example, was generally weak, shoppers hit the stores at the end of the month in search of post-holiday bargains, and continued to do so through January. February brings spring merchandise with it each year, but shoppers will go for it only if the weather says, think pink - as they apparently did this year.

``February provided further evidence that consumers buy when they want to buy, not when retailers feel they should buy,'' said Jeffrey Feiner, an analyst at Lehman Bros. Inc.

This meant that many shoppers paid regular prices on spring clothing rather than waiting for markdowns. But in the search for bargains, they headed for discount stores for many of their needs, instead of going to department or mall stores.

The Goldman Sachs index showed that discounters' sales rose 8.7 percent last month. That was well above the 3.2 percent increase in department store sales and the 2.9 percent rise in sales in the ``hard goods'' sector, which includes merchants of furniture, hardware and computers.

``Discounters did well along a very broad base,'' said Richard Baum, a retail analyst at Goldman Sachs. ``They did a very good job on seasonal merchandise, like horticultural products. But they did good with consumables, too.''

Department stores that cater to lower-income shoppers also outperformed their peers. Kohl's, for example, said its sales rose 10.3 percent, and Profitt's sales rose 7 percent.