A mild start to the first week of Spring, but it doesn't last all week. Turning cooler and wet on Wednesday as a stalled cold front sinks southward, bringing the rain with it. This is in connection with an area of low pressure that will strengthen in Nebraska. The cold front will stay north of the Stateline Tuesday and that keeps us cloudy but dry through the afternoon with temperatures making it into the low 60's. Overnight the front will sink south into northern Illinois by Wednesday morning.This will be the focal point for rain to develop through Wednesday.
A few showers will be possible Wednesday morning but then coverage increase through the afternoon. Temperatures will be cooler than what we will see today, but still warm enough to support rain across the region, with the swath of snow in central Wisconsin north of the freezing line and low pressure track.
A few thunderstorms will develop in central Iowa Wednesday afternoon and will track eastward, allowing for a few rumbles of thunder Wednesday evening. Stronger thunderstorms look to stay southwest of the region where there is better moisture and instability present. This includes western Illinois, southern Iowa, and most of Missouri.
The rain will continue overnight into Thursday morning as the low pressure heads to the northeast into Michigan by Thursday afternoon. Cold air will then filter in behind the system into Thursday morning as the low passes overhead. This would allow for a change over to a winter mix and then all light snow through Thursday afternoon. With warmer temperatures profiles and not a lot of lingering moisture northern Illinois doesn't look to see any significant accumulation. Higher totals will stay north of the area where there are currently Winter Storm Watches in place through central Wisconsin.
If the low pressure track sinks farther south, then the Stateline could be in line for more snowfall, make sure to check back for more updates.