Query: What type of storm is a major threat to Charleston in the summer and early fall?
Context: The highest temperature recorded within city limits was 104 °F (40 °C), on June 2, 1985, and June 24, 1944, and the lowest was 7 °F (−14 °C) on February 14, 1899, although at the airport, where official records are kept, the historical range is 105 °F (41 °C) on August 1, 1999 down to 6 °F (−14 °C) on January 21, 1985. Hurricanes are a major threat to the area during the summer and early fall, with several severe hurricanes hitting the area – most notably Hurricane Hugo on September 21, 1989 (a category 4 storm). Dewpoint in the summer ranges from 67.8 to 71.4 °F (20 to 22 °C).