Hey super -- I forget the year but one time we had a quick band of snow move through at evening rush hour with temps in the teens. It had been very cold for a few days but no prior snow, so there was no chemical residue on roads. Most places got just a quarter inch, but tire action from cars flash froze it and all roads became sheets of ice. Salt trucks were helpless because roads were jammed. The area became paralyzed and people were trapped in their cars for hours -- up to 10 hours or more. My wife's mom was in her car for 7 hours for her 12 mile drive. Many people just abandoned their cars and walked off.
I have 0.4 in Germantown. I just need 0.1 more to get me to a cool 20" for the winter.