The next winter storm is in the slot ready to make a move on the Midwest this weekend. Finally, models are coming together on a common solution as to where the storm will track and the sensible weather that will impact the region.
Since the storm track holds the key to this entire forecast, I'll start showing the projected positions of Saturday's surface low on our 3 major models. Below each will be the associated snowfall forecasts of that model.
Now the NAM, the outlier.
As you can see the EURO and GFS are in good sync taking the low through EC Iowa. That keeps the majority of the precipitation in my area as rain. The exception would be a mix to start and a change to snow to end. The significant snows stay well into the NW half of Iowa.
The NAM being the outlier is further SE with its track and brings snow further east into parts of eastern Iowa and extreme NW Illinois. I suspect the model is showing its cold bias and I don't give it much chance of verifying.
The Weather Prediction Center does show this for odds of 2 or more inches of snow.
All the models do bring in some big time precipitation totals for February on the order of .50 to nearly 2.00". The GFS is very bullish (probably too much so) showing 1.80" in Cedar Rapids and Iowa City. Most of that is rain falling on ground that is covered with more than a foot of snow in spots. That along with moisture from melting snow is likely to create some run-off issues where the heavier rains occur.
With regards to timing, precipitation is not expected in my area until Friday night. Initially some mixed freezing rain, sleet or snow is possible, especially north of HWY 30. By Saturday morning rain is the dominate form as warmer air seeps in ahead of the advancing storm. As the system passes much colder air will wrap into the region Saturday night changing the rain to light snow or snow showers. That could hang around for a time Sunday morning before it all comes to an end.
At this point howling NW winds are expected to surge southeast bringing a significant cool-down Sunday. Along with falling temperatures, the winds will be formidable with gust over 50 mph possible. Where significant snow falls this will create near whiteout conditions, especially in NC Iowa and Minnesota. Here's the gusts shown on the EURO Sunday morning. 57 mph would meet severe thunderstorm criteria!
From what I can see tonight, it's close but no cigar on significant snow with this potent storm. Rain should rule, sloppy and cold. Roll weather....TS