Characterization of the Ashepoo-Combahee-Edisto (ACE) Basin, South Carolina


False color map of ACE Basin showing Deposition Facies in the Shallow Aquifer System

Weather patterns found in the ACE Basin are influenced by its latitude, the southern Appalachian Mountains, and the Gulf Stream. Three weather stations, Edisto Island (1956-present), Walterboro (1948-present), and Yemassee (1896-present), provide data to describe the subtropical climate of the Basin. A weather station also exists at the ACE Basin National Estuarine Research Reserve (NERR) field station at Bennett's Point, but data have only been collected there since 1995. In general, hot, humid summers, mild winters, and ample precipitation throughout the year characterize the ACE Basin climate. The relatively local scale of the moderating effect that the Gulf Stream imparts is evident in differences in mean temperature between Edisto Island and Yemassee, only 48 km (30 mi) inland. Average maximum and minimum temperatures for the ACE Basin in July and August are 32oC (90oF) and 21oC (70oF), respectively. In January, the average mean temperature is 10oC (50oF) with large interannual fluctuations occurring. The ACE Basin receives 100-130 cm (40-50 in) of precipitation per year with maximum precipitation occurring during summer months because of thunderstorms. Between September and February, winds commonly come from the north, northeast, or west. By March the predominant directions are west, southwest, and south, a tendency that persists through August. Average speeds are greatest from December through May. The ACE Basin can also experience severe weather from thunderstorms and hurricanes.