<P> South Carolina has a humid subtropical climate, with hot summers and mild winters . On average, between 40 inches (1,000 mm) and 80 inches (2,000 mm) of precipitation falls annually across the state . Tropical cyclones, and afternoon thunderstorms due to hot and humid conditions, contribute to precipitation during the summer and sometimes fall months, while extratropical cyclones contribute to precipitation during the fall, winter, and spring months . Tornadoes happen mostly in the spring with a secondary peak in November . Hail and damaging winds often occur in summertime thunderstorms . Tornadoes are very uncommon in the summer unless a tropical disturbance were to spawn one . </P> <P> South Carolina has a humid subtropical climate (Köppen climate classification Cfa), although high elevation areas in the "Upstate" area have less subtropical characteristics than areas on the Atlantic coastline . 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). Winter temperatures are much less uniform . 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). Further inland in the Piedmont, temperatures average between 50 ° F (10 ° C) during the day and 32 ° F (0 ° C) at night . </P> <Table> <Tr> <Th> Event </Th> <Th> Measurement </Th> <Th> Date </Th> <Th> Location </Th> <Th> County </Th> </Tr> <Tr> <Td> Highest temperature </Td> <Td> 113 ° F (45.0 ° C) </Td> <Td> Jun. 29, 2012 </Td> <Td> USC Columbia </Td> <Td> Richland, South Carolina </Td> </Tr> <Tr> <Td> Lowest temperature </Td> <Td> − 19 ° F (− 28.3 ° C) </Td> <Td> January 21, 1985 </Td> <Td> Caesars Head </Td> <Td> Greenville </Td> </Tr> </Table> <Tr> <Th> Event </Th> <Th> Measurement </Th> <Th> Date </Th> <Th> Location </Th> <Th> County </Th> </Tr>

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