New Smyrna Beach enjoys pleasant air and water temperatures year round. Average temperatures range from the mid 60s (19°C) in the winter months to the high 80s (30°C) in the summer months. Brief late-afternoon showers are common in July, a trend that gradually diminishes in the months that follow.

Oceanside New Smyrna Beach is a barrier island bordered by the Atlantic Ocean on the east and the Indian River, also known as the Intracoastal Waterway, on the west. Two bridges on the northern end provide access to the island. The communities of Oak Hill and Edgewater are located on the Indian River, as is New Smyrna Beach's mainland.

Area topography consists mostly of the low altitudes associated with the Florida coast. The average elevation is 9 feet (2.75m), with a maximum elevation of 15 feet (4.58m). Ocean tides average 3 feet (0.9m), changing every 6 hours. Tides run 4 to 8 feet (1.2 to 2.4m) through Ponce Inlet and 2 feet (0.6m) in the Indian River.