I'd want some good tires - winter tires - even studded tires, on a spare wheel set or more preferably a spare bike. Not sure where you are located but 20f probably means ice and snow. And I bet uphill will really suck while downhill at 20f with ice could be... Interesting ??
. If you have good days wit snow free roads it's easier and faster with "regular" tires. Just remember that like all season car tires, your bike tires will be affected by cold weather, not just by snow and ice. If you can switch wheels easily it'll be easier on you.
Final point. In the army we learned mechanical stuff (like bikes) freeze up and seize up if brought in and out from cold to hot to cold, etc. If you can store in a garage or porch it'll be easier on the bike though maintenance is critical.
I tried it years ago early spring to late fall, not all winter and even then, riding into wind made early morning rides a living hell and then there was those sudden slides and loss of control on ice to spice up the ride and I had zero hills (up or down) to entertain me..