Every day a new wave of tourists and businessmen from Caracas, Bogota, Quito and Buenos Aires pour into this city with their suitcases empty and their wallets full.

They clog custom lines at Miami International. They fill up the shops on Flagler Street and the rooms in the Omni Hotel.

They come here to play, to buy, and to salt away their dollars.They leave with their suitcases full of Nikon cameras, Gucci shoes and handbags, Givency shirts, Bill Blass neckties, and Sears oil filters. They also snap up condominiums, warehouses, shopping centers and financial institutions.

The visitors, numbering almost a half million this year, signal an important and largely ignored social and economic phenomenon. Simply put, Miami has quietly become the new capital city of Latin America. Evidence:

More than 80 multinational firms now operate their Latin American headquarters out of the Miami area -- most from the palm-shaded suburb of Coral Gables.

With 5.7 million foreign airline passengers arriving and departing each year (more than 90 percent from Latin America), Miami has become a major Latin transportation center.

Half the tourists now coming to Miami are Latins. And they are far more well-heeled than their Yankee counterparts. The typical Latin spends an estimated $1,000 during his visit here compared with $408 for U.S. and Canadian visitors.

Miami has become a major international banking center. Eleven major U.S. banks have opened Miami branches during the last decade to cater to the Latin trade. Eight foreign banks have opened similar branches.

Thousands of South and Central Americans are buying second homes in Miami. Whole developments have been taken over by oil-rich Colombians and Venezuelans. A recent study found Latins had purchased 61 percent of the units in a dozen new luxury condominiums in three choice locations, including Key Biscayne.

Cargo shipments out of the port of Miami, 80 percent of which go to Latin countries, have tripled in the last 10 years.

That Miami should become the key U.S. link to South America is largely an accident of history and geography.

Located near the nation's southernmost tip, it has long pictured itself as the gateway to South America. But not until thousands of Cubans fled Fidel Castro's revolution did it begin to realize that dream. The Cubans, who make up 56 percent of the city's 370,000 population, transformed Miami.

Other cities have larger Spanish-speaking populations. Los Angeles is the home of 1.6 million Latins, most of Mexican ancestry; New York is the home of 1.3 million Latins, the majority originally from Puerto Rico.

What sets Miami apart is the totality of its Latin culture, and the types of Latins who settled here.

It may be the only major U.S. city where a stranger can wander an hour in the downtown shopping district without hearing a word of English. It is probably the only city where it's as easy to find platanos (fried bananas) as hamburgers.

"We consider this a Latin city," declares Miami Mayor Maurice Ferre, who came from Puerto Rico. "It's the only city in the United States where a completely different culture has been transplanted. Other cities have transplanted neighborhoods of Italians or Poles. Here you have a whole part of a nation uprooted en masses and transplanted."

While many of the Mexicans and Puerto Ricans who migrated to other cities were unskilled and uneducated, the uprooted Cubans included much of their homeland's social and economic elite.

They now make up a nation within a nation. They have their own banks, newspapers, radio stations, stores, nightclubs, import-export businesses.

"It is a vibrant community that is self-sustaining," says Mayor Ferre. "You can shop, go to movies, watch television, listen to the radio, do business, all in Spanish."

This hints at one of Miami's greatest appeals for Latins. They simply feel comfortable here.

Officially, the city and its schools are bilingual. That means that all city notices, applications, ballots and bulletins are printed in Spanish as well as English. The Miami Herald, Florida's most influential newspaper, prints a daily Spanish edition, El Herald.

There are some other very practical reasons for Miami's emergence as a Latin American tourist, shopping and business capital.

The same climate and location that made it a haven for decades from Northeast and Midwest winters now draw South Americans during their winter months -- July and August. A visit to Disney World in Orlando has become a must stop for families, a Latin status symbol.

Inflation and the need for consumer goods and manufacturing equipment have made almost anywhere in the United States an attractive place for Latins to shop and invest. Miami, with 782 flights weekly to the Caribbean and South America, is easiest and cheapest for Latins to get in and out of.

"Here they can mix business and pleasure," says an Argentine emigre, businessman Maurice Rizikow. "Their own language and people are here. They can take a vacation and make, money at the same time."

Consumer prices are so high in much of South America that a trip to Miami makes good economic sense for many Latins, he says. "Look at it this way. Merchandise costing $2,000 in Miami sells for $4,000 in Argentina. So people fill their suitcases. When they get home they sell some things, keep some and get a free vacation out of the deal."

Rizikow is one of this city's most astute observers of South American habits, almost a Latin Horatio Alger.

He came here in 1965, speaking broken English, and began selling imitation fur coats out of a one-room shop on the fourth floor of a rundown downtown building. Today, at 49, he is the Miami connection for some of the freest spending big money men this city has ever seen. He owns a 45-shop downtown shopping mall and is making plans to build a $38 million hotel aimed at the Latin trade.

Hardly a week goes by, he says, without two or three South American businessmen dropping by to ask advice on U.S. investments. With unstable governments at home, most are looking for a haven for their money, a hedge against political turmoil.

"When politics change in a country, people begin to become afraid," Rizikow says. "The first thing they do is take their money out."

Chief beneficiaries to date have been Miami banks and real estate interests.

International banking, a decade ago only a minor business here, is booming. Only New York among U.S. cities has more banks specializing in international transactions. Miami's 11 Edge Act banks (branches of out-of-state financial institutions to conduct international business) have deposits over $1 billion. One major local bank, Southeast First National, claims international deposits over $600 million.

Another major bank, Republic National, is controlled by Ecuador interests; two area banks are controlled by Venezuelans, one by Panamanians.

The real estate picture is even more dramatic. Fred S. Smith, president of The Keyes Co., largest real estate firm in the South, estimates that 30 to 35 percent of the new real estate developments in Miami's Dade County are being financed by Latin American interests. Sixty percent of the luxury condominiums on Bickell Avenue in Key Biscayne, and about 30 percent of those on Miami Beach, are now being bought by Latins, he says.

Some of the investors are members of the upper-crust elites that have controlled most Latin countries for generations. Others are part of Latin America's new middle class.

Most are motivated by fear of political upheaval, says Smith. "Almost all of them could get a much better return on their money in their own country, but they're looking for stability."

"These people aren't fleeing their countries," he adds." They just don't want to get caught with all their eggs in one basket."

Originally, most of the condominiums were bought simply as investments. But now many wealthy South Americans are looking at Miami for more permanent ties.

"It works like this," one observer relates. "First, you buy a condo and come here for Easter. Then you decide to come up for a couple weeks in August. There's not a lot to do here in August so one of the kids says, 'Why don't we buy a boat?' That's another $45,000. When you've spent $45,000 for a damn boat you start spending long weekends here. The next thing you know someone says, 'You ought to buy a warehouse.'"

The Latinization of Miami has not been problem-free. Old Miami and new Miami simply don't understand one another, or even communicate much. Largely, it's a clash of cultures.

As Cuban exiles and other Latins have moved into new neighborhoods, there's been a steady exodus of whites northward into suburban Broward County. "I never go to downtown Miami anymore except for the Orange Bowl parade," a Fort Lauderdale housewife said. "I don't know why all those people don't learn to speak English like Americans."

"Much of the city, including the Chamber of Commerce and the Miami Herald, are scared to death about what's happening," says Mayor Ferre. "The Georgians, Mississippians and Carolinians who run those places keep looking north rather than south. Mecca for them isn't Mexico City. Mecca is Atlanta. They want to do everything the way Atlanta does it, not the way Latins do it."

However, the Americans who run multinational firms like Exxon, Cargill, Borden and Lockheed are placing their bets on the new Miami. Its Coral Gables suburb is home for the Latin offices of 76 multinationals.

Most of the firms made the move after considering a half dozen or more Latin American cities. Coral Gables, for instance, beat out Mexico City, Bogota, Caracas, San Juan, Buenos Aires, Sao Paulo and Rio when E. I. duPont deNemours was picking a new Latin headquarters last year.

Although a host of factors played a part in the decision, the principal consideration was communication, according to Kenneth Trelenberg, the company's assistant Latin American director. The company decided it was simply faster to telephone, fly and mail to South America from Miami than from any South American country.