Seeking your advice

Real Snow tires, buy a version with a spare. you do not want to deal with a flat and have no spare in the winter.

(It has been 14 years since I drove in snow)

 

I voted No, but that is on the presumption you don't use the original factory tires in winter. After one or two winters, my OEM tires (both Prii, from 2009 and 2012) did turn into sled runners.

Real winter tires will make all the difference. Even better All-Season tires (which are not real winter tires, and quickly degrade to 3-season tires) will be better than the factory tires.

I use separate sets of wheel rims for winter, both on the Prius and on our Subaru. This lets me swap on my own schedule, without having to put them on prematurely or deal with the long waiting lines at the tire shops when the first snows are forecast. It also reduces both the cost, and prevents the inevitable rim and bead damage, of twice-yearly tire re-mounting.

 

I live in Minnesota and have a 2013 series 4. I had to replace the original tires at 17,000 because of a flat tire and an incentive of promotional pricing on 4 new tires. I also had a 2010 with original tires too. In both instances, even in 10 inches of snow the Prius went right through unplowed side roads without a problem. I am impressed with how well the car will go through snow.
I would love to lower it like our California members, but that won't work here..... sigh..

 

Is it 2016 model year Prius you're interested in? Or a third generation, 2010 through 2016? I'm not clear on "Prius four".

There's a steel Corolla rim that'll work with 15" snow tires, btw.

 

Within a week of getting our 2010, in mid-November, I got Michelin X-Ice snow tires mounted on Corolla steel rims. They're well behaved and quiet on bare roads, which is by far the norm for us, on the BC west coast in winter. They grip a lot better than all-seasons on black ice too.

It's basically our December through March set up, even though we don't get much snow. If and when we do get snow, it can be a wet dump. Up to 6" you're ok if careful. Somewhere between 6 and 10 inches, depending on moisture content, how icy it is at the bottom, the car will hang up due to the low underbody clearance, no matter what the tires are.

This is what I used:

Corolla steel rim, part no: 42611-02471 (2003-2008 corolla or matrix, CE, LS, S)
steel rim lug nuts, part no: 90942-01007 (plain, open-ended, galvanized)

 

Like with any vehicle purchase, I think it boils down to what you want, and what your priorities will be.

I'm a huge Prius supporter, but IMO it's simply NOT the best winter conditions driver.
Sure it can be made to work. With good snow tires, which IMO are a necessity if you are going to attempt to do a lot of snow/ice driving.

But my opinion a combination of things that make up "Prius" all translate into it being less than an optimal winter conditions driver.
I know that some people claim that it's just great, and they have driven them through blizzards and etc, but IMO, low ground clearance, on Gen 3 and 4 covered under body, electric motors, electric motor torques on start up, regenerative brakes, aggressive traction control, and often low rolling resistance tires, all together translate into a reason a Prius would NOT be my first choice for repeated winter driving.

That being said, most people report that with commitment to a good set of snow tires, The Prius is fine. Some even report better than average winter handling.
People obviously own and operate Prius in Chicago.

Honestly, what I would do, would try to politely get some feedback from owners of Prius you might see in a parking lot.
I suspect they would tell you Prius "works" with Snow Tires.

I think if winter conditions driving is a priority or routine, there are better choices for a primary vehicle. If Prius was my ONLY vehicle? I don't know if I would want it if I lived where I had to repeatedly drive in snow and ice.

 

Will a prius be a sled in Chicago weather?

No.
In MY never to be humbled opinion, if you're in an urban environment, then the road is either going to be filled with other small, front wheel drive cars, or the WX is going to be too bad for ANYONE to be out.
The difficulty, as always, is deciding on which is the case and humans are fairly ill equipped for this task.
There are lots better 'winter cars' out there than the Prius, but IMHO a Prius makes just about as much sense in Chicago as it does out on the left coast.
There's a misconception of sorts that you need to be in a Rubicon rated Jeep in order to survive winters, which is sorta not true because when the weather really closes in you're going to get log-jammed on the interstates along with all of the other drivers that are ice bound.

Remember the Atlanta snowpocalypse a few years ago?
You can't cheat physics.