An area of showers and thunderstorms will continue to work east across the state this morning. Once the majority of this is through the area, we will see the sun try to pop through the cloud cover across southwest Iowa by late afternoon which will be just enough for severe thunderstorms to develop roughly 6-8 PM from southwest up through central Iowa and slowly track to the southeast. We might even have a few storms off into west central Iowa that try to form as well.
The main threats will be hail, damaging winds and heavy rainfall. The dynamics do support a isolated tornado threat in southwest Iowa if storms can stay mature. Both the ISC models and public guidance are very amped on rainfall totals so some training of storms will be likely where these do develop. This activity will drift east overnight tonight exiting the state by Sunday morning.
We will watch for some patchy dense fog to develop overnight tonight across the northwest half of the state. A second round of severe weather will follow Sunday evening. The latest thinking is the timing will be similar to tonight with storms developing 8-10 PM across south central to southeast Iowa. The dynamics look a bit more organized with this one to support all modes of severe weather including hail, damaging winds, heavy rainfall and an isolated tornado. The frontal zone responsible for this severe weather threat will slowly push the activity east of the state after midnight as we work into early Monday morning.