I've been riding in snow for nearly 60 years. This link on winter cycling matches my experiences:

Copenhagenize.com - Bicycle Urbanism by Design: Overcomplicating Winter Cycling - Why It's Bad

I wear normal office clothing (suit or trousers/sport jacket). Over them I use a LL Bean Stowaway Gortex hooded coat, Lands End 2.5 Layer rain pants, Grandoe ski gloves, and NEOS Villager overshoes. It's good down to 0 F and I just unzip for cooler conditions. Best of all, it goes on or off in just a few minutes. If it is above 20 or not snowing/raining, I'll forgo the overshoes and over pants.