In those areas, you'd be on the expressways. Coming in early, you'd mostly be fine, Kennedy to Ohio to St Clair or something depending on where your parking is. You're talking early enough that it won't be too awful.

OTOH, going home at 5 would be terrible. A couple times a month, I end up driving to Skokie around that time (from Lakeview on the north side) and the traffic is almost always terrible.

Look into the Metra options (someone upthread mentioned that NMH has its own shuttle from Ogilvie/Union, oh, google found it easily http://www.northwestern.edu/uservice...instation.html), like toomanybooks says, at least on Metra you can read or work or do something beyond agonizing over the traffic.