* WHAT...Flash flooding caused by excessive rainfall is possible. * WHERE...Portions of north central Illinois and northeast Illinois, including the following areas, in north central Illinois, Boone, De Kalb, La Salle, Lee, Ogle and Winnebago. In northeast Illinois, Central Cook, DuPage, Eastern Will, Grundy, Kane, Kendall, Lake IL, McHenry, Northern Cook, Northern Will, Southern Cook and Southern Will. * WHEN...Until Noon CDT today. * IMPACTS...Excessive runoff may result in flooding of roads, parking lots, rivers, creeks, streams, and other low-lying and flood-prone locations. Creeks and streams may rise out of their banks. Flooding may occur in poor drainage and urban areas. * ADDITIONAL DETAILS... - Torrential rain producing thunderstorms have been ongoing across portions of far northern Illinois early this morning, with areas of flash flooding likely. Thunderstorms are expected to gradually expand southward toward and beyond daybreak. This will result in the threat for flash flooding also expanding southward to around the I-80 corridor,

