CHICAGO -- The Flash Flood Watch that was issued Thursday evening for the area west and north of Chicago has been expanded to include much of northeast Illinois including the city of Chicago until late Friday night.
Northeast Illinois counties under the combined Flash Flood Watch are shaded in green on the highlight map above include Winnebago, Ogle, Lee, Boone, McHenry, Lake, DeKalb, Kane, DuPage, Cook, Kendall, La Salle, Grundy and Will Counties.
Ongoing showers/thunderstorms to the west and north of Chicago will continue but gradually weaken this afternoon.
Then storms are expected to redevelop this afternoon and evening over northwestern Illinois, spreading back over the Flash Flood Watch area and farther south into central Illinois and east into Indiana.
With the high moisture-laden air mass in place, storms will be rather slow-moving and may “train”, tracking repeatedly over the same areas, causing localized flooding problems.
As a cold front moves through from the west later tonight/early Saturday, storms are forecast to slowly weaken and eventually move east of our area.