Hurricanes and Tornadoes That Hit Sullivans Island, SC

The nearest NOAA station with 1991–2020 climate normals is Sullivans Is, SC, 1 mile west of Sullivans Island at 5 feet. July is the warmest, with an average high of 91°F and low of 73°F; January is the coolest, at 59°F and 37°F. August is the wettest at 6.7 inches of precipitation on average and November the driest at 3.0 inches; the year adds up to 51.6 inches. June to November, the hurricane season months, bring 59% of the year's precipitation (30.5 of 51.6 inches); the other six months are drier. September has brought the most of the 114 tropical systems that passed within 75 miles (35); a normal September there has highs of 86°F and 5.5 inches of precipitation. Highs reach 90°F on about 55 days a year, almost all from May to September. Lows fall below freezing on about 18 nights a year. That 51.6 inches is more than at 59 of the 78 South Carolina stations used on this site (76%). Charleston, 9 miles west, has its own station (Charleston City, SC): 44.5 inches a year, 7.1 less than here, and a July average high of 88°F against 91°F.

Water temperature at the NOAA tide station Charleston, SC, 5 miles west, averaged 86°F in July and 54°F in January over 2021–2025. It averaged 80°F or warmer from June to September. Sea level at the Charleston tide gauge, 5 miles from Sullivans Island, has risen 1.38 ± 0.04 inches per decade from 1901 to 2025, NOAA's linear trend; at that pace it is 13.8 inches in a hundred years. That is faster than at 82 of the 144 U.S. gauges with a NOAA trend.

Since 1996, the National Weather Service has logged 389 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Sullivans Island: 193 flash floods, 166 thunderstorm wind reports, 23 lightning strikes, 4 floods and 3 heavy rain events. They killed 1 person and injured 8, and the NWS estimated $10.4 million in property and crop damage. The strongest thunderstorm gust on record here was 82 mph, on May 9, 1997. August has had the most flash floods, 73 of 193. Of the 241 South Carolina cities on this site with a flash flood on record, 232 have had fewer than Sullivans Island.

Flood insurance policyholders in Sullivans Island's ZIP code 29482 have filed 894 claims with the National Flood Insurance Program since 1979, and were paid $22.2 million for buildings and contents, in the dollars of each year. The most came from Hurricane Hugo in 1989: 607 claims (68% of all) and $20.6 million, then Hurricane Floyd in 1999 with 82 and October severe storms in 2015 with 32. 89% 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, 95 have fewer than Sullivans Island.