The Storm Prediction Center has issued a TORNADO Watch effective until 1am Thursday morning for the following counties, Howard, Mitchell, Floyd, Chickasaw, Fayette, Clayton, Winneshiek and Allamakee. This replaces the previous watch which expired at 7pm. Thunderstorms are continuing to fire along a cold front in western Iowa and along a boundary in southern Wisconsin. Some of the storms may still produce tornadoes in the watch area in Iowa, but large hail and damaging straight line winds will become the main threats after sunset this evening.