Climate of South Carolina

Worldwide climate classifications

South Carolina has a humid subtropical climate, with hot summers and winters that are not extremely cold. 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 are most common 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 cyclone is present.

Temperatures

South Carolina has a humid subtropical climate (Koppen 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 daytime temperatures 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 near 60 °F (16 °C) and overnight lows near 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.

Monthly Normal High and Low Temperatures For Various South Carolina Cities
City	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Charleston	59/37	62/39	69/46	76/52	83/61	88/68	91/72	89/72	85/67	77/55	70/46	62/39
Columbia	55/34	60/36	67/44	76/51	83/60	89/68	92/72	90/71	85/65	76/52	67/43	58/36
Greenville	50/31	55/34	63/40	71/47	78/56	85/64	89/69	87/68	81/62	71/50	61/41	53/34
[1]

Precipitation

Annual average precipitation in South Carolina

While precipitation is abundant the entire year in almost the entire state, the coastline tends to have a slightly wetter summer, while inland March tends to be the wettest month. During the cold season, extratropical cyclones is the main cause of precipitation, while during the summer, tropical cyclones and thunderstorms forming due to afternoon heating are the main causes of precipitation. A lee side rain shadow from the Appalachian Mountains lowers annual precipitation across central portions of the state.^[2] Inland sections average 40 inches (1,000 mm) to 50 inches (1,300 mm) of rainfall, while near the coast 50 inches (1,300 mm) to 60 inches (1,500 mm), and the Piedmont receives 70 inches (1,800 mm) to 80 inches (2,000 mm) of precipitation.^[3]

Snowfall and ice

Snowfall in South Carolina is not very excessive with coastal areas receiving less than 1 inch (2.5 cm) on average. It is not uncommon for areas along the coast (especially the southern coast) to receive no measurable snowfall in a given year. The interior however receives more snow. The snowiest location in the state averages as much as 12 inches (30 cm) of snow a year in the Blue Ridge Mountains of the state. Freezing rain is more common than snow and even rain across much of the state in the winter months.

Tropical cyclones

Hurricane Hugo (1989)

The state is prone to tropical cyclones. This is an annual concern during hurricane season, which is from June through November. The peak time of vulnerability for the southeast Atlantic coast is from early August to early October when tropical cyclone frequency is highest.^[4] Major hurricanes can impact the Palmetto state, though there are no category 5 impacts on record.^[5] Two of the stronger hurricanes to strike South Carolina in recent times are Hurricane Hazel (1954) and Hurricane Hugo (1989), which were of category 4 strength. For weaker systems, rainfall and spin-up tornadoes in the outer bands are the main impacts to the state. The wettest known tropical cyclone to impact South Carolina was a tropical depression named Jerry in 1995 which stalled nearby and had previously been a tropical storm across Florida.^[6] Jerry brought nearly 19 inches (480 mm) of rainfall to upstate South Carolina.^[7]

Thunderstorms and tornadoes

South Carolina averages around 64 days of thunderstorm activity per year. Most thunderstorms occur during the summer. South Carolina is vulnerable to tornadoes. Some notable tornadoes have struck South Carolina and the state averages around 50 tornadoes annually.^[8] There have been no F-5 tornadoes on record but over a dozen F-4 tornadoes have occurred in many counties in South Carolina.

See also

• Climate of the United States
• List of wettest tropical cyclones in South Carolina
• United States rainfall climatology
• List of South Carolina weather records

References

1. ^ http://www.ustravelweather.com/weather-south-carolina/
2. ^ South Carolina State Climatology Office. South Carolina Climate. Retrieved on 2008-03-18.
3. ^ National Atlas.gov. Average annual precipitation for South Carolina. Retrieved on 2008-03-08.
4. ^ National Hurricane Center. Graphic showing seasonal activity by date. Retrieved on 2008-03-18.
5. ^ Eric S. Blake, Edward N. Rappaport, and Chris Landsea. The Deadliest, Costliest, and Most Intense United States Tropical Cyclones From 1851 to 2006 (and other frequently requested hurricane facts).
6. ^ National Hurricane Center. Atlantic Hurricane Track Database. Retrieved on 2008-03-18.
7. ^ David M. Roth. Tropical Storm Jerry Color-Filled Rainfall Graphic. Retrieved on 2008-03-18.
8. ^ National Climatic Data Center. Annual average number of tornadoes. Retrieved on 2006-10-24.