EF1 tornado in Charleston County, South Carolina

A National Weather Service Storm Survey Team confirmed an EF-1 tornado with an estimated maximum wind speed of 105 mph on the southwest side of Seabrook Island, South Carolina. The same storm that produced a tornado at Edisto Beach, produced a second tornado on Seabrook Island, which developed just west of the intersection of Seabrook Island Road and Camp Christopher Lane, then traveled northeast for about 1.25 miles snapping off or uprooting dozens of trees and breaking off numerous large branches. The most significant tree damage occurred on or near a golf course. Additionally, a garage was significantly damaged at a home when a large tree fell on it. Several other homes sustained minor damage due to trees falling near them or large branches falling on them. The tornado then dissipated just northeast of the intersection of Seabrook Island Road and The Lookout Road.

A severe quasi-linear convective system (QLCS) moved through southeast South Carolina during the early morning hours of April 13, 2020 ahead of an approaching cold front. The environment ahead of the QLCS was unusually unstable for this time of day and year, with gulf moisture spreading upper 60 F to near 70 F dewpoints into a warm sector across the Southeast United States and mid level lapse rates around 7 C/km helping produce mixed layer convective available potential energy (MLCAPE) as high as 2000 J/kg across Southeast South Carolina. Within the warm sector, very strong vertical shear associated with a 50 knot plus low and mid-level jet, effective bulk shear around 70 knots, effective storm relative helicity in the 400-600 m2/s2 range, and VAD wind profiles displaying large, curved low-level hodographs were supportive of well organized convection and potentially embedded supercell thunderstorms in a QLCS capable of producing a prolonged path of damaging winds and strong long-track tornadoes. As the QLCS swept through Southeast South Carolina, a few supercell thunderstorms became exceptionally strong while partially breaking away from the main line of thunderstorms, producing widespread wind damage and strong long-track tornadoes.

A total of 13 confirmed tornadoes occurred across Southeast South Carolina, including a long track EF-4 tornado in Hampton County that took the lives of 5 people and injured 60 others along an approximately 24 mile path. The EF-4 tornado was the first to have occurred across Southeast South Carolina and the last to have occurred in the entire state of South Carolina since November 17, 1995, almost 25 years prior. This particular tornado was associated with a storm that produced a destructive path of straight-line wind damage and series of long track and intermittent tornadoes for over 150 miles, beginning in Screven County, Georgia, then continuing northeast across Hampton County, Colleton County, Dorchester County, and Berkeley County, South Carolina before leaving the area and eventually shifting offshore along the South Carolina coast. Two other storms were responsible for the remaining tornadoes across the area, most of which occurred from a single storm occurring across Edisto Island, Seabrook Island and Kiawah Island. Outside the EF-4 tornado in Hampton County, straight-line winds near a passing tornado claimed the life of one individual and injured one in Colleton County, while another tornado caused 6 injuries across Berkeley County.