South Carolina has a humid subtropical climate (Köppen climate classification Cfa), although high elevation areas in the "Upstate" or "Upcountry" area have less subtropical characteristics than areas on the Atlantic coastline. In the summer, South Carolina is hot and humid with daytime temperatures averaging between 86–93 °F (30–34 °C) in most of the state and overnight lows averaging 70–74 °F (21–23 °C) on the coast and from 66–73 °F (19–23 °C) inland. Winter temperatures are much less uniform in South Carolina. Coastal areas of the state have very mild winters with high temperatures approaching an average of 60 °F (16 °C) and overnight lows in the 40s°F (5-8 °C). Inland, the average January overnight low is around 35 °F (2 °C) in Columbia and just below freezing in the Upstate. While precipitation is abundant the entire year in almost the entire state, the coast tends to have a slightly wetter summer, while inland March tends to be the wettest month. Snowfall in South Carolina is not common, with coastal areas receiving less than an inch (2.5 cm) annually on average. It is not uncommon for areas on the coast (especially the southern coast) to receive no recordable snowfall in a given year. The interior receives a little more snow, although nowhere in the state averages more than 6 inches (15.24 cm) of snow annually.The state is occasionally affected by tropical cyclones. This is an annual concern during hurricane season, which lasts from June 1 to November 30. The peak time of vulnerability for the southeast Atlantic coast is from early August to early October, during the Cape Verde hurricane season. Two memorable Category 4 hurricanes to hit South Carolina were Hazel (1954) and Hugo (1989). South Carolina averages around 50 days of thunderstorm activity a year, which is less than some of the states further south, and it is slightly less vulnerable to tornadoes than the states which border on the Gulf of Mexico. Still, some notable tornadoes have struck South Carolina and the state averages around 14 tornadoes annually.
