The Storm Prediction Center has issued a Severe Thunderstorm Watch effective until 11pm this evening for the following counties, Audubon, Buena Vista, Calhoun, Carroll, Cherokee, Clay, Crawford, Dickinson, Emmet, Harrison, Ida, Lyon, Mills, Monona, O’Brien, Osceola, Palo Alto, Plymouth, Pocahontas, Pottawattamie, Sac, Shelby, Sioux, Woodbury, Dakota NE, Thurston NE, Burt NE, Washington NE, Douglas NE, Sarpy NE, Cass NE, Otoe NE and Union SD. Showers and thunderstorms will develop this afternoon and into this evening over the watch area. The main threats look to be from large hail and damaging winds. There could also be an isolated tornado as well. Along with the severe weather threat comes some heavy rain. A Flash Flood Watch is in effect this evening and overnight across the northwestern sections of the state for the possibility of heavy rainfall from these storms. Watch out for ponding of water and rapid rises in creeks and streams especially if storms train over the same areas during the evening and overnight.