FFWLOT The National Weather Service in Chicago has extended the * Flash Flood Warning for... Northeastern Cook County in northeastern Illinois... DuPage County in northeastern Illinois... Northwestern Will County in northeastern Illinois... * Until 1030 PM CST. * At 942 PM CST, Doppler radar and automated rain gauges indicated a line of heavy rainfall extending from just south of the Chicago Loop to near Orland Park. This line of showers and thunderstorms is drifting slowly eastward with rainfall rates in excess of 1 inch per hour. Worsening of flood impacts is expected shortly after rainfall onset. HAZARD...Flash flooding. SOURCE...Radar and automated gauges. IMPACT...Rapid-onset flooding of creeks, streams, drainage ditches, streets, underpasses, low-lying areas, and other poor drainage areas. * Some locations that will experience flash flooding include... Chicago, Naperville, Cicero, Hammond, Evanston, Bolingbrook, Skokie, Des Plaines, Orland Park, Oak Lawn, Berwyn, Wheaton, Oak Park, Downers Grove, Elmhurst, Lombard, Ohare Airport, Carol Stream, Romeoville and Plainfield.

ESFLOT Waves of showers and thunderstorms are expected this afternoon and evening across portions of northeastern Illinois and northwestern Indiana. The highest rainfall rates are expected this evening as atmospheric moisture increases to near record levels for January and a line of showers and thunderstorms moves through the area. Small isolated corridors may receive rainfall in excess of 1-2 inches, especially in areas where storms orient in a more southwest to northeast direction. Rainfall amounts of this magnitude sometimes cause localized flooding of streams and poor drainage areas during the winter months. Areas with streets, drainage ditches, and stormwater drains impacted by late fall and early winter vegetation debris may be especially susceptible to flooding. This outlook means that elevated water levels and potential impacts are possible, but not yet certain, based upon the latest forecasts. Persons with interests along area streams and rivers should closely monitor the latest forecasts. In addition, ensure that nearby stormwater drains and ditches are cleared of debris.

* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...A portion of northeast Illinois, including the following counties, Cook, DuPage, and northern Will. * WHEN...Until 1100 PM CST. * IMPACTS...Underpasses may be flooded. Roads and streets may be flooded. * ADDITIONAL DETAILS... - At 700 PM CST, Doppler radar and automated rain gauges indicated rainfall moving into the area with rates in excess of 0.5 inches per hour. Up to 1 inch of rainfall has been observed since earlier this afternoon. Additional showers and thunderstorms moving into the area over the next hour will likely cause flooding of roadways and poor drainage areas. - Some locations that will experience flooding include... Chicago, Aurora, Joliet, Naperville, Cicero, Hammond, Arlington Heights, Evanston, Schaumburg, Bolingbrook, Palatine, Skokie, Des Plaines, Orland Park, Tinley Park, Oak Lawn, Berwyn, Mount Prospect, Wheaton and Hoffman Estates. - http://www.weather.gov/safety/flood