From the National Weather Service:
A Flash Flood Watch remains in effect through Sunday morning for Logan-De Witt-Piatt-Champaign-Vermilion-Cass-Menard-Scott-Morgan-Sangamon-Christian-Macon-Moultrie-Douglas-Coles-Edgar-Shelby-Cumberland-Clark-Effingham-Jasper-Crawford-Clay-Richland and Lawrence counties
Periods of heavy rain are expected to develop today, and continue through Saturday night. The rainfall will develop in response to the remnants of Tropical Storm Gordon moving over southern Illinois combining with an old frontal boundary that is stalled over the area. Heavy rainfall amounts of 4 to 6 inches will be possible in some areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS: A Flash Flood Watch means that conditions may develop that lead to flash flooding. Flash flooding is a VERY DANGEROUS SITUATION. You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.
