Hurricanes and Tornadoes That Hit Saint Helena Island, SC

The nearest NOAA station with 1991–2020 climate normals is Beaufort Mcas, SC, 12 miles northwest of Saint Helena Island at 37 feet. July is the warmest, with an average high of 92°F and low of 75°F; January is the coolest, at 60°F and 40°F. August is the wettest at 6.5 inches of precipitation on average and May and November the driest at 2.5 inches; the year adds up to 45.1 inches over 68 days with at least a tenth of an inch. June to November, the hurricane season months, bring 61% of the year's precipitation (27.4 of 45.1 inches); the other six months are drier. September has brought the most of the 104 tropical systems that passed within 75 miles (31); a normal September there has highs of 86°F and 4.0 inches of precipitation. Highs reach 90°F on about 73 days a year, almost all from May to September. Lows fall below freezing on about 17 nights a year. That 45.1 inches is more than at 12 of the 78 South Carolina stations used on this site (15%). Edisto Island, 18 miles northeast, has its own station (Edisto Is Middleton Plantation, SC): 52.1 inches a year, 7.0 more than here, and a July average high of 90°F against 92°F.

Since 1996, the National Weather Service has logged 199 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Saint Helena Island: 177 thunderstorm wind reports, 13 lightning strikes, 8 flash floods and 1 flood. None is recorded as killing or injuring anyone; the NWS estimated $347,000 in property and crop damage. The strongest thunderstorm gust on record here was 75 mph, on June 17, 2016. August has had the most flash floods, 5 of 8. Of the 241 South Carolina cities on this site with a flash flood on record, 103 have had fewer than Saint Helena Island.

Flood insurance policyholders in Saint Helena Island's ZIP code 29920 have filed 1,242 claims with the National Flood Insurance Program since 1979, and were paid $19.4 million for buildings and contents, in the dollars of each year. The most came from Hurricane Matthew in 2016: 767 claims (62% of all) and $11.2 million, then Hurricane Irma in 2017 with 237 and October severe storms in 2015 with 24. 87% of the claims carry the name of a storm or flood event; the rest have no event name. Of the 110 South Carolina cities on this site with 10 or more claims, 99 have fewer than Saint Helena Island.