General Climatology

• As a subtropical climate in the northern section of the mid-latitudes, South Carolina enjoys four distinct seasons. Summers are long and marked by high humidity and heat. Winters are short and marked by mildly cold temperatures and little to no freezing precipitation. Spring and fall are mild, with average temperatures in the 70s to mid-80s. Both spring and early fall are characterized by the rise in precipitation and increased risk of tropical storms and hurricanes.
  
  

Thunderstorms and Tornadoes

• In terms of states experiencing tornadoes, South Carolina ranks in the top 20 for annual frequency. Thunderstorms are common, especially during spring and early fall months, producing heavy rain and frequent lightening strikes, especially along the Midlands region. Tropical storms and hurricanes can increase the likelihood of thunderstorms and tornadoes from May through late September -- the primary hurricane season. Typical tornado strength in the state of South Carolina is less than EF-1 but can include strengths as high as EF-4.
  
  

Hurricanes and Tropical Storms

• Tropical storms are more frequent in South Carolina than hurricanes. A tropical storm includes winds over 34 knots but less than the minimum 64 knots that distinguish hurricanes. Hurricane Hugo, making landfall in September 1989, was the most recent destructive hurricane to hit South Carolina. Tropical depressions, tropical storms and hurricanes create hazardous and destructive weather conditions for the coastal areas of South Carolina, but typically result only in thunderstorms in other areas of the state.
  
  

Winter Weather Conditions

• Accessibility of the warm Gulf Stream near the coast and proximity to the Appalachian Mountains combine to provide South Carolina short, mild winters. The mountains block cold air currents coming from states further inland. The Gulf Stream provides warm air currents from over the Atlantic Ocean. The average temperature in winter is just above freezing, resulting in scattered instances of sleet, snow, or other frozen precipitation, usually limited to the mountain regions. Areas within the Appalachian mountains get a measurable level of snowfall perhaps two or three times in the course of a winter. Comparatively, areas in the Midlands and Lowlands experience snowfall less than once a year.