The National Weather Service is predicting up to three more inches of rain in parts of already-water-logged eastern Iowa. National Weather Service meteorologist Brian Pierce says it’s uncharted territory in the city of Cedar Rapids where the Cedar River is swelling far beyond flood stage.

"We have not seen anything like this before. This is going to be an historic hydrologic event," he says. "The volume of water that we are forecasting to be going by at any certain point is off our charts."

By Friday at its expected crest, every second there will be 120,000 cubic feet of water rushing through the downtown area that’s being flooded out by the Cedar River. "To put that in perspective that would be the equivalent of the Mississippi River in the Quad Cities at a very low and moderate flood, but you’re trying to put the same volume — amount of water — into a much smaller river basin," he says.

Weather records indicate 1923 was the last time the Cedar River reached such levels in Cedar Rapids. Every bridge but the Interstate-380 bridge over the Cedar River in Cedar Rapids has been closed to traffic.