Flocks of Canadian "snowbirds" - winter residents - are expected back in the Miami area when the northern winter sets in. And so many tourists from oil-rich Venezuela have been visiting here this summer that airlines have added extra flights from Caracas.

Cheaper air fares, a couple of harsh winters up north, and a soaring number of visits - and investments - from Latin Americans have to helped the Miami area resume some of its economic growth interrupted by the national recession in the early 1970s.

But this time Miami, not Miami Beach, is setting the pace. For years Miami took second place to its sister across the bay, where tourists jammed the miles of hotels and condominiums. But Disney World opened in central Florida, Caribbean tourist attractions grew more popular, and the mostly beach-less Miami Beach went into a slump it still has not shaken (though the beach is nearly restored and other improvement efforts are under way).

Miami Beach promoters hope Florida voters in November will approve casino gambling along a 21-mile, ocean-front strip stretching north from Miami Beach as a way to revive the area.

But Miami already is on the upswing. And though some argue that casinos would help further, others say they would slow down development by changing the image of the city.

Meanwhile, Miami's Latin connection has been clicking. In the last two years 10 banks doing Latin American trade have opened says Thomas Bromar president of First Federal Savings & Loans of Miami. Another six or seven banks are planning to open here, he adds. General Electric, dupont and Lockheed recently announced plans to open Latin American headquarters in the Miami area.

Miami is estimated to be 55 percent Latino, due mostly to the great influx of Cubans. Bilingual signs are seen in many places.

"What you've got is basically a Latin American city within the U.S.," says Jim Reid, director of Miami's planning department. And southern Florida, especially the Miami area, has become a major attraction for Latins seeking a more stable place to invest their funds than at home.

As for Latin tourism, "We think we're getting the tip of the iceberg," says Reid. Many shops and places like the Omni International Hotel, which opened in Miami a year ago, cater heavily to Latins.

But Miami is not depending solely on its Latin connection. The city, Dade County, and the state government have made a commitment to help revitalize downtown Miami. Almost all the land for a 30-acre, $300-million downtown government office complex has been acquired. Some buildings have been completed or are under construction. A new convention center and sports arena seating 18,000 are planned.

The city plans a $795-million rapid-transit system and has received nearly $1 million in federal planning funds for an $82-million, 3.7 mile downtown overhead "people mover." Both are criticized by some as a waste of taxpayer money.

Miami's resurgence is not without problems, however. Officials point out that much of the housing in the area is old or overcrowded. There is a lack of skilled workers, and the city does not have as much manufacturing as many other areas.

A study last year by the planning department of Dade County, which includes Miami, projected "continued, but slowly, employment growth" for the area through 1990. The decline this year in construction has turned the former condominium glut into a predicted shortage.

Unemployment levels among Cubans and blacks have been running about two to three times higher than among whites. Population growth has slowed in Dade County, but has picked up in Broward County, just to the north.