I commute in work clothes ("office casual") as the longest leg of my multi-modal commute is about 2.5 miles.
When the temperature goes below about 60 F, I wear a shell (Showers Pass "Syncline" https://www.rei.com/product/896068/s...ke-jacket-mens).
Below about 50 F, I add a long-sleeve Polar Fleece shirt.
In the mid-30s F, I add a balaclava.
Below 30F, I add water- and wind-proof pants (North Face; can't find the exact ones now...)
Below 20F, I add a thinner base layer shirt (Under Armour).
Below 10F, I add Polar Fleece pants (Under Armour) over my work pants and under the shell.
Below about -10F, I will put up the hood of my shell.
On the hands, once it gets below mid-30s I wear Pearl Izumi "lobster mitts" (https://www.pearlizumi.com/US/en/sho.../p/14341508428)
The coldest I've commuted in is -20F, and the equipment ^^ keeps me comfortable.