The Storm Prediction Center has issued a Severe Thunderstorm Watch effective until 5am Monday morning for the following counties, Adair, Adams, Audubon, Calhoun, Carroll, Cass, Crawford, Fremont, Greene, Guthrie, Harrison, Mills, Monona, Montgomery, Page, Pottawattamie, Ringgold, Sac, Shelby, Taylor and Union. A squall line is moving into the state at this time, with the threats being from large hail and damaging straight line winds. Other watches could be posted and warnings are likely as these storms quickly move to the ESE.