Yesterday's ensembles signaled that south may be the way to go. I'm not putting much faith in the nw outlier GFS.
A few days ago models were showing a deep western trough and eastern ridge, with a torch surging north into the lakes. Since then, models have gradually transferred energy from the west to the north... now too much pressing for Iowa.
I haven't read any posts mentioning it, but it appears much of this snow will be falling during the daylight on Saturday, which only adds to the greatness of the storm.
Some recent model op runs have been good for Iowa, but the model ensembles are suggesting this overrunning/cutter pattern has a better chance of being suppressed to the south of Iowa. I'm hopeful, but not optimistic.
Tropical Tidbits just added a bunch of Euro data, including 06z and 18z runs. The ECMWF has made of bunch of their stuff free. Sadly, that does not include precip-type or snowfall maps, but it's still pretty nice.
There was a heated discussion about the frequency of significant snowstorms in Detroit and Chicago on another thread. I just checked my records and it's pretty ugly. Over the last fifteen winters I have only had four 9" snowstorms. That's it... FOUR!!! My last 9" snowstorm was in early February of 2015, seven years ago. Cedar Rapids is a 1-6" climate.
The surface low is passing directly over Cedar Rapids. The temp near my house just jumped to 37º while the temp is in the 20s a couple miles north. All I got out of this system was a light dusting at the end.