Flash flood warnings have dotted the state this morning and parts of central and eastern Iowa are still under a flash flood watch. Parts of northern Iowa got up to eight inches of rain overnight, while northwest Iowa had severe storms and twisters.There’s tornado damage in far northwestern Iowa in and near Sheldon. A building was destroyed, a tractor-trailer was overturned & there’s some tree damage and power lines down but no serious injuries are reported. Two tornadoes were reported in Osceola County not far from the Minnesota border.Black Hawk and Grundy County in northeast Iowa are under a flood warning this morning after four to six inches of rain fell there overnight. Black Hawk County Emergency Operations Officer Lawrence Tisor says part of one roadway was closed for a time.There was some minor flash flooding and part of Highway 57 was closed. Tisor says the water has now receded and Highway 57 is open. There were several reports of lightening strikes along with the storm. Tisor says there wasn’t any serious damage.The National Weather Service says there were no major roads closed in Grundy County — but there are numerous gravel roads that remain closed or are washed out.