Climate of South Carolina

The northwestern area of the state can receive impacts from both Atlantic basin storms moving westward from the coast and also occasionally very heavy rainfall and flooding from storms originating from the Gulf of Mexico that move inland towards the northeast after making landfall from the Florida Panhandle to Louisiana.

In the summer, South Carolina is hot and humid with temperatures during the day averaging near 90 °F (32 °C) across most of the state with overnight lows near 70 °F (21 °C).

Coastal areas of the state have very mild winters with high temperatures averaging about 60 °F (16 °C) and overnight lows close to 38 °F (3 °C).

A lee side rain shadow from the Appalachian Mountains lowers annual precipitation across central portions of the state.

Annual snowfall across South Carolina varies greatly in frequency and amounts, from being quite rare with little to no accumulation in the southern coastal areas to being very common annually with 2 to 3 small snowfall events in the Upstate, particularly along and north of Interstate 85, which essentially is built along the 850 to 900 feet elevation contour.

The snowiest location in the state, above 2,000 feet in elevation, averages 12 inches (30 cm) of snow a year in the Blue Ridge Escarpment area.

Along the southern coastal barrier islands, frozen precipitation of any type is very rare, with only a few snow events on record.

For weaker systems, rainfall and spin-up tornadoes in the outer bands are the main impacts to the state.

Most of the state has warmed by one-half to one degree Fahrenheit (300-600 m°C) in the last century, and the sea is rising about one to one-and-a-half inches (2.5-3.8 cm) every decade.

Higher water levels are eroding beaches, submerging low lands, and exacerbating coastal flooding.