Rain has been falling for much of the day Saturday and will continue to into Sunday. So far rain has been fairly light, but persistent during the afternoon and evening of Saturday. Accumulation so far has been under a half an inch (as of Saturday evening) but more is coming.
This looks like a lot of rain, but the atmosphere is lacking moisture. Precipitable water values (moisture content of the atmosphere) are fairly low.
Typically we look for 1 to 2 inches of precipitable water for a decent rain, but right now the entire Midwest is below an inch. Rain will still continue into Sunday morning and some areas could pick up around an inch of rain.
There will be a little bit more moisture around with the next storm system that moves in Sunday.
There will be higher moisture levels, and in fact more instability down to the south and east. Rain will move into the Midwest Monday night into Tuesday.
This system will likely add another inch of precipitation. So when it's all said and done here's the rainfall totals though Tuesday evening:
On top of the rain, there will be strong winds and colder air moving in on Tuesday. It's possible some parts of northeast Iowa into Minnesota and Wisconsin could experience a wintry mix or some wet snowflakes Tuesday as it gets colder.
There will really be a chill in the air the rest of the week. Temperatures will be in the 30s and 40s in the afternoons. Check out Wednesdays highs:
First the rain... then the cold.