he National Weather Service in Chicago has issued a * Special Marine Warning for... Nearshore Waters from Winthrop Harbor to Northerly Island... Open Waters from Winthrop Harbor to Michigan City out to Mid Lake... * Until 245 PM CDT. * At 1247 PM CDT, severe thunderstorms were located along a line extending from 14 nm north of McHenry to 36 nm northwest of Elgin, moving east at 40 knots. HAZARD...Wind gusts to 40 knots and large hail. SOURCE...Radar indicated. IMPACT...Small craft could be damaged in briefly higher winds and suddenly higher waves. Large hail could result in structural damage. * Locations impacted include... Winthrop Harbor, Waukegan Harbor and Wilmette Harbor.