Charleston: Geography and Climate

Prior to 1960, Charleston proper was limited to the South Carolina peninsula bounded on the west and south by the Ashley River, on the east by the Cooper River, and on the southeast by an excellent harbor almost completely land-locked from the Atlantic Ocean. The city has expanded to include other areas, but most residents still think of Charleston as the peninsula. In fact, the physical size of Charleston has increased from approximately 17 square miles in 1975 to 97 square miles today. A chain of barrier islands between Charleston's mainland and the Atlantic Ocean adds sandy beaches and marshland to the region's geography.

Charleston's proximity to the Atlantic Ocean provides a temperate climate. During the winter months temperatures on the peninsula can be as much as 15 degrees warmer than inland because of the ocean's influence. In summer, sea breezes cool the city to a temperature about three degrees below higher country. The summer is Charleston's rainiest season with 41 percent of the annual rainfall occurring in the form of thundershowers and occasional tropical storms. Hurricanes threaten in late summer and early fall. It is estimated that Charleston is affected by hurricanes every 4.62 years. In September 1989 Hurricane Hugo inflicted more than $5 billion in property damage to the region. In September 1999 Hurricane Floyd forced hundreds of thousands of people to evacuate Charleston. More recent hurricanes were Charley and Gaston, both in 2004.