Rock County Emergency Management Coordinator, Sheriff's Sergeant Shena Kohler is watching the water of the Rock River rise. The National Weather Service has issued a flood warning. the Rock river is forecast to reach minor flood stage by Sunday. Kohler doesn't expect flooding to be serious, but says it may cause some damage on lowland and agricultural areas adjacent to the rive in areas near Afton and Janesville. Flooding may also impact low land in the Blackhawk Island area of Lake Koshkonong on the north side of the lake. She advises motorists to avoid travling on any roadways with high water.