Like eager shoppers looking for great buys, leading national retailers are flocking to Washington in search of great sales -- crowding up against stores that are already here.

During the past few months, five retailers have disclosed plans to open new stores or enter the Washington area, already considered one of the most competitive markets in the country.

R. H. Macy & Co. is expected to open at least two stores in the area in the next three years under the name Bamberger's. Saks Fifth Avenue, a fixture for years on Wisconsin Avenue in Bethesda, plans to open a second store in Virginia in 1987.

Caldor Inc., a rapidly growing discount chain, plans to open three to five stores in the area during the next two years. And Carson Pirie Scott, a major Chicago department store chain, also will gain a foothold in the area when it completes its acquisiton of 20 Pants Corral stores from Giant Food Inc.

Also planning to enter the Washington market is the Denver-based Pace Membership Warehouse Inc., one of a growing number of wholesale-membership warehouse companies that sell a wide variety of items ranging from food to tires to housewares at a discount to card-carrying members.

In addition, one of the nation's largest factory-outlet malls, the Potomac Mills mall, is slated to open this summer in Dale City.

Washington "is a good, solid market that has our kind of customers . . . middle income and upscale," said Ray Treiger, senior vice president of R. H. Macy Properties, the real-estate division of R. H. Macy & Co.

"Washington has a lot of demographics that make for a good Caldor customer," echoed Caldor Chairman James M. Guinan. "Our customer tends to be an upscale suburban customer. There are plenty of those in Washington."

The surge of new retailers -- coming just eight years after Bloomingdale's, Neiman-Marcus and I. Magnin entered the Washington area -- is expected to intensify already fierce competition among local stores to hold on to their share of consumers' dollars. Faced with sluggish sales, retailers are running frequent sales promotions.

The onslaught appears likely to spur increased promotions and price competition as well as prompt major store renovations designed to keep the Washington shopper's eye from roving.

It is "surely going to shake up the environment," predicted Louis W. Stern, executive director of the Marketing Science Institute, a Cambridge, Mass., marketing research firm. "Someone is going to lose because the market is not going to grow" to accommodate all the newcomers. "But the consumer is going to make out like a bandit," he predicted.

"Everyone will become more promotional," predicted Neal J. Fox, president of Raleighs Store Corp. Fox noted that Bamberger's, a 21-store subsidiary of Macy's that operates in the mid-Atlantic area, is one of the most promotional stores in the industry.

"The consumer will benefit the most" as competitors try to meet Bamberger's challenge, he said.

The news of Macy's plans to open Bamberger stores has had the biggest impact on the Washington retail community of any of the announcements.

Bamberger's entry "will intensify competition in all department-store merchandise lines," predicted William D. Striegl, district manager for J. C. Penney Co. "That will be good for the retail community and certainly good for consumers."

Macy's has plans so far for two Bamberger stores in Northern Virginia in the next three years, one at the Tysons II shopping center in Fairfax and another at Pentagon City in South Arlington. A third site at Springfield Mall is also under study.

Retailing executives note that for the most part, Bamberger's is Macy's twin. However, they added, Bamberger's is probably a bit more promotional than Macy's and sells more trendy clothes, partly because its customers are younger than the Macy's customer.

Increased sales promotions will not be the only thing consumers will see. Shoppers also can expect store renovations as area chains strive to make their stores as fresh and exciting as the new ones are expected to be. Even before the latest announcements, many chains in the Washington area already were in the midst of major makeovers.

The Hecht Co. has perhaps the most ambitious undertaking under way, building a new, $40 million downtown five-floor department store to take the place of its aging complex at Seventh and F streets NW. The new store, featuring off-white marble and granite, will be located on G Street between 12th and 13th streets NW. It is scheduled to open this fall.

At the same time, Hecht's is redoing its Parkington store in Arlington, spending $5 million to remodel virtually every square foot of sales space and the store's exterior.

The interior renovation has been completed, and now the company is redoing the exterior. The entire renovation is expected to be finished within a month. Meanwhile, the rest of Parkington Shopping Center, which is owned by Hecht's parent May Department Stores Co., has been demolished and is being rebuilt into a new, $70 million, 125-store mall that will include a brand-new Penney's store. The mall is scheduled to open next spring.

Woodward & Lothrop Inc. is also planning major changes in its downtown store, largely to accommodate the merchandise and offices now being housed in its North Block Annex, which is being torn down and will be replaced by an office-hotel complex. At the same time, the chain, like Hecht's, is remodeling a number of its suburban stores.

Garfinckel's flagship store at 14th and F streets NW is undergoing a $10 million refurbishing, marking the first time the store has been completely overhauled since it opened in 1930. And Raleighs, under new ownership, also is trying to create a new look for its downtown store on Connecticut Avenue NW.

Also putting on a new look are Sears, Roebuck & Co., K mart Corp., Penney's and Montgomery Ward & Co. Inc., all of which are engaged in nationwide programs to upgrade their stores and merchandise in an attempt to attract more affluent customers here and elsewhere.

With Macy's arrival, the renovations are certain to continue.

"They build good stores and big stores," noted Woodies Chairman Edwin Hoffman. "Their new stores will be exciting. . . . We're going to be very aware of what they stand for and be very competitive with our merchandise, the way our stores look and the service we give," he said.

With Bamberger's coming to Tysons II, "a lot will be happening at Woodies' Tysons Corner store ," Hoffman added. "It is a highly successful store, and we want to make sure it will be competitive so there will be a lot of work done there" before Bamberger's arrives.

Hecht's plans to redo its Tysons store as well. "That store will be remodeled by the time Bamberger's opens here," said Hecht's Chairman J. Warren Harris. "That's the only specific thing we've planned so far."

Harris, Hoffman and other retailers clearly are concerned about the new competition. "This area is probably just at its saturation point," commented Harris. "Macy's arrival will probably shift volume; but hopefully it won't be from us."

Population growth in this area is relatively stable, which will intensify the battle among retailers, store executives predicted. "There's not a whole lot more dollars to be captured" if the population level remains about the same, said a retailing expert on the Greater Washington Board of Trade. "So the struggle here will be for market share, with dollars shifting from store to store," he said.

"If Bamberger's comes in, it is not likely to expand the number of dollars spent in retail stores," commented Allan Pennington, president of the retail consulting firm Pennington Associates. "Their money will come out of the hides of someone else. And the two chains most likely to lose most from it will be its most direct competitors: Woodies and Hecht's."

Harris is not unmindful of this prediction, noting that shortly after Bamberger's arrived in Baltimore two years ago, two local department store chains -- Hochschild Kohn and Stewart & Co. -- went out of business. Although Harris said their departure from the retailing scene may have been caused by other factors, he said that he and other retailing executives are keeping the demise of those stores in mind.

Because the Washington market is far more competitive than the Baltimore market, some officials say Bamberger's entry could spell even greater trouble for area chains. "The market isn't going to take a lot of growth," said Hoffman. Bamberger's share "will have to come from someplace. We want to make sure it won't come out of our hide."

Despite concern over market share, some area retailers said they would welcome Bamberger's arrival if the chain decides to open a store in Springfield Mall where the major retailers are Penney's, Montgomery Ward and Garfinckel's.

"It would be especially beneficial to us if they come to Springfield Mall," said Penney's Striegl. "They will add a great deal to the mall, which has been lacking a full-line department store."

Until last week, Macy's officials appeared reluctant to disclose their Washington plans, responding to queries by saying the company had "no definite commitment" to build stores here.

However, last week Macy's Treiger acknowledged that the company hopes to arrive here soon. "The board of directors hasn't approved any transaction yet; nonetheless, we have a working commitment and are proceeding in good faith on plans and documents" to open in Pentagon City and Tysons II. The first Bamberger's would open at Tysons II in the fall of 1987, with the second store at Pentagon City scheduled to open in early 1988.

Macy's also is "considering seriously" establishing a Bamberger's at Springfield Mall, he said. Macy's Chairman Edward S. Finkelstein examined the site about three weeks ago in a tour that included a helicopter ride over the area.

Macy's "is one of the best-managed retail companies in the country today," said Stern of the Marketing Science Institute. Finkelstein "has done absolutely phenomenal work . He took the flagship store in Manhattan -- a store that was in such bad shape it could have been blown up -- and turned it around into a Bloomingdale's-type of operation. He boutiqued it, making it a series of specialty stores within a store. Its cellar of food shops and kitchenwares has become an absolute classic. He added pizazz and entertainment, making it a fun place with a sense of excitement and fun."

Although analysts compare the look to Bloomingdale's, Macy's is considered a more aggressive promoter. "It is very aggressive in pricing, running weekly specials, so it is recognized as a value merchant more than Bloomingdale's," commented Walter F. Loeb, a financial analyst with Morgan Stanley & Co.

Caldor is widely considered by analysts as one of the nation's best discount store chains. A subsidiary of Associated Dry Goods, the Connecticut-based chain calls itself "the upscale discounter," selling brand-name clothing and appliances to middle- and upper-income customers at cut-rate prices. It is particularly known for goods such as blenders, toasters, cameras and sporting equipment, which account for 70 percent of its business.

"Caldor occupies the upscale niche of discount stores," said Pennington. "It is a significant notch above K mart and different than Bradlees in that it has a stronger focus on hard goods. Bradlees has a stronger emphasis on soft goods such as clothing and linens."

Although its arrival comes just two years after Bradlees opened 11 stores here, as K mart is upgrading its stores and as Zayre is opening a new store in the District, Caldor does not appear to pose the competitive threat to other discounters that Macy's does to the major department stores, retail executives said.

One of the reasons is that Caldor is aiming at the discount market, where there is more room because "that market has been abandoned by the conventional retailer" and even some traditional budget chains, which are upgrading and prospecting for the more affluent customer. As a result, Segall said, there is plenty of room in the area for discounters.

"We welcome them," said John Hechinger, president of Hechinger Co., which competes with some of Caldor's merchandise lines.