Hurricanes and Tornadoes That Hit Summerville, SC

The nearest NOAA station with 1991–2020 climate normals is Charleston International Airport, SC, 11 miles southeast of Summerville at 40 feet. July is the warmest, with an average high of 91°F and low of 74°F; January is the coolest, at 60°F and 39°F. August is the wettest at 7.0 inches of precipitation on average and November the driest at 2.7 inches; the year adds up to 52.7 inches over 74 days with at least a tenth of an inch. June to November, the hurricane season months, bring 62% of the year's precipitation (32.8 of 52.7 inches); the other six months are drier. September has brought the most of the 99 tropical systems that passed within 75 miles (32); a normal September there has highs of 85°F and 6.0 inches of precipitation. Highs reach 90°F on about 64 days a year, almost all from May to September. Lows fall below freezing on about 22 nights a year. That 52.7 inches is more than at 65 of the 78 South Carolina stations used on this site (83%). Moncks Corner, 15 miles northeast, has its own station (Moncks Corner 4 N, SC): 52.4 inches a year, 0.3 less than here, and a July average high of 93°F against 91°F.

Water temperature at the NOAA tide station Charleston, SC, 22 miles southeast, 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, 22 miles from Summerville, 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 491 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Summerville: 381 thunderstorm wind reports, 81 flash floods, 21 lightning strikes, 6 floods and 2 heavy rain events. They killed 1 person and injured 12, and the NWS estimated $11.5 million in property and crop damage. The strongest thunderstorm gust on record here was 98 mph, on March 15, 2008. July has had the most flash floods, 26 of 81. Of the 241 South Carolina cities on this site with a flash flood on record, 228 have had fewer than Summerville.

Flood insurance policyholders in Summerville's 3 ZIP codes have filed 461 claims with the National Flood Insurance Program since 1979, and were paid $9.0 million for buildings and contents, in the dollars of each year. The most came from October severe storms in 2015: 244 claims (53% of all) and $5.4 million, then Hurricane Matthew in 2016 with 47 and Hurricane Debby in 2024 with 24. 74% 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, 90 have fewer than Summerville.