Miami is a global city in southeastern Florida, in the United States. Miami is the county seat of Miami-Dade County, the most populous county in Florida. With an estimated population of 409,719 in 2007, Miami is the largest city within the Miami metropolitan area, which is the seventh-largest metro area in the United States with over 5.4 million residents. The Miami Urbanized Area (as defined by the Census Bureau) was the fifth most populous urbanized area in the U.S. in the 2000 census with a population of 4,919,036. The United Nations estimated that in 2007, Miami had become the fourth largest urbanized area in the country, behind New York City, Los Angeles, and Chicago.

Miami is ranked as a global city for its importance in finance, commerce, media, entertainment, arts and international trade. The city is home to many company headquarters, banks, and television studios. It is an international center for popular entertainment in television, music, fashion, film, and the performing arts. The city's Port of Miami is known for accommodating the largest volume of cruise ships in the world and is home to many cruise line headquarters. Miami is also home to the largest concentration of international banks in the United States.

As of 2008, Miami is undergoing a large building boom with 24 skyscrapers that are expected to rise over 400 feet (122 m) currently under construction in the city. Miami's skyline ranks third in the U.S., behind New York City and Chicago, and 18th in the world according to the Almanac of Architecture and Design. The city currently has nine of the ten tallest skyscrapers in the state of Florida, with the tallest being the 789-foot (240 m) Four Seasons Hotel & Tower.

In 2008, Miami was ranked as "America's Cleanest City" according to Forbes Magazine for its year-round good air quality, vast green spaces, clean drinking water, clean streets and city-wide recycling programs. In 2008, Miami was also ranked the 3rd-richest city in the United States and the world's 22nd-richest city in a UBS study.

At only 35.68 square miles (92 km2) of land area, Miami has the smallest land area of any major U.S. city with a metro area of at least 2.5 million people. The city proper is home to less than 1 in 13 residents of South Florida. Additionally, 52% of Miami-Dade County's population doesn't live in any incorporated city. Miami is the only major city in the United States bordered by two national parks, Everglades National Park on the west, and Biscayne National Park on the east.

Miami and its suburbs are located on a broad plain between the Florida Everglades to the west and Biscayne Bay to the east that also extends from Florida Bay north to Lake Okeechobee. The elevation of the area never rises above 40 ft (12 m) and averages at around 6 ft (2 m) above mean sea level in most neighborhoods, especially near the coast. The highest undulations are found along the coastal Miami Rock Ridge, whose substrate underlies most of the eastern Miami metropolitan region. The main portion of the city lies on the shores of Biscayne Bay which contains several hundred natural and artificially created barrier islands, the largest of which contains Miami Beach and South Beach. The Gulf Stream, a warm ocean current, runs northward just 15 miles (24.1 km) off the coast, allowing the city's climate to stay warm and mild all year.

Miami has a true tropical climate, specifically tropical monsoon (Köppen climate classification Am), with hot & humid summers and warm & mostly dry winters. The city does experience cold fronts from late October through March. However, the average monthly temperature for any month has never been recorded as being under 64.4 °F (January averages 67 °F). Most of the year is warm and humid, and the summers are almost identical to the climate of the Caribbean tropics. In addition, the city gets most of its rain in the summer (wet season) and is mostly dry and mild in winter (dry season). The wet season lasts from May to October, when it gives way to the dry season, which features mild temperatures with some invasions of cool air, which is when the little winter rainfall occurs — with the passing of a front. The hurricane season largely coincides with the wet season.

In addition to its sea-level elevation, coastal location and position just above the Tropic of Cancer, the area owes its warm, humid climate to the Gulf Stream, which moderates climate year-round. A typical summer day does not have temperatures below 75 °F (24 °C). Temperatures in the high 80s to low 90s (30-35 °C) accompanied by high humidity are often relieved by afternoon thunderstorms or a sea breeze that develops off the Atlantic Ocean, which then allow lower temperatures, although conditions still remain very muggy. During winter, humidity is significantly lower, allowing for cooler weather to develop. Average minimum temperatures during that time are around 60 °F (15 °C), rarely dipping below 40 °F (4 °C), and the equivalent maxima usually range between 70 and 77 °F (19-24 °C).

Miami has never recorded a triple-digit temperature; the highest temperature recorded was 98 °F (37 °C). The coldest temperature ever recorded in the city of Miami was 30 °F (-1 °C) on several occasions. Miami has only once recorded snowfall, on January 20, 1977. Weather conditions for the area around Miami were recorded sporadically from 1839 until 1900, with many years-long gaps. A cooperative temperature and rainfall recording site was established in what is now Downtown in December, 1900. An official Weather Bureau Office was opened in Miami in June, 1911.

Miami receives abundant rainfall, one of the highest among major U.S. cities. Most of this rainfall occurs from mid-May through early October. It receives annual rainfall of 58.6 inches (1488 mm), whereas nearby Fort Lauderdale and Miami Beach receive 63.8 in (1621 mm) and 48.3 in (1227 mm), respectively, which demonstrates the high local variability in rainfall rates. Hurricane season officially runs from June 1 through November 30, although hurricanes can develop beyond those dates. The most likely time for Miami to be hit is during the peak of the Cape Verde season which is mid-August through the end of September. Due to its location between two major bodies of water known for tropical activity, Miami is also statistically the most likely major city in the world to be struck by a hurricane, trailed closely by Nassau, Bahamas, and Havana, Cuba. Despite this, the city has been fortunate in not having a direct hit by a hurricane since Hurricane Cleo in 1964. However, many other hurricanes have affected the city, including Betsy in 1965, Andrew in 1992, Irene in 1999, and Hurricanes Katrina and Wilma in 2005. In addition, a tropical depression in October 2000 passed over the city, causing record rainfall and flooding. Locally, the storm is credited as the No Name Storm of 2000, though the depression went on to become Tropical Storm Leslie upon entering the Atlantic Ocean. Miami has been identified as one of three cities in the United States most vulnerable to hurricanes, mainly due to its location and it being surrounded by ocean and low-lying coastal plains, the other two cities being New Orleans and New York City.

Miami is home to many entertainment venues, theaters, museums, parks and performing arts centers. The newest addition to the Miami arts scene is the Adrienne Arsht Center for the Performing Arts, the second-largest performing arts center in the United States after the Lincoln Center in New York City, and is the home of the Florida Grand Opera. In it, is the Ziff Ballet Opera House, the center's largest venue, the Knight Concert Hall, the Carnival Studio Theater and the Peacock Rehearsal Studio. The center attracts many large scale operas, ballets, concerts, and musicals from around the world and is Florida's grandest performing arts center. Other performing arts venues in Miami include the Gusman Center for the Performing Arts, Coconut Grove Playhouse, Colony Theatre, Lincoln Theatre, New World Symphony House, Actor's Playhouse at the Miracle Theatre, Jackie Gleason Theatre, Manuel Artime Theater, Ring Theatre, Playground Theatre, Wertheim Performing Arts Center, the Fair Expo Center and the Bayfront Park Amphitheater for outdoor music events.

The city is home to numerous museums as well, many of which are in Downtown. These include the Bass Museum, Frost Art Museum, Historical Museum of Southern Florida, Jewish Museum of Florida, Lowe Art Museum, Miami Art Museum, Miami Children's Museum, Miami Science Museum, Museum of Contemporary Art, Vizcaya Museum and Gardens, Wolfsonian-FIU Museum and the Miami Cultural Center, home of the Main Miami Library. Other popular cultural destinations in the area include Jungle Island, Miami MetroZoo, Miami Seaquarium, and parks and gardens in and around the city; there are over 80 parks in Miami. The largest and most popular parks are Bayfront Park and Bicentennial Park (located in the heart of Downtown and the location of the American Airlines Arena and Bayside Marketplace), Fairchild Tropical Botanic Garden, Tropical Park, Watson Island, Morningside Park and Key Biscayne.

Miami is also a major fashion center, home to models and some of the top modeling agencies in the world. Miami is also host to many fashion shows and events, including the annual Miami Fashion Week and the Mercedes-Benz Fashion Week Miami held in the Wynwood Art District.