In the past I have just worn regular glasses down to probably 0*F, then some over-the-glasses goggles when it's colder than that. Cheap ski goggles.

I had LASIK done this year, so now I'm wearing wrap around safety glasses, I suspect I'll continue to wear them down to 0 or so again. I may investigate other stuff for colder temps. When it gets well below zero I have to be careful to not leave any exposed skin, I have gotten frost nip on the cheeks before, at about -25*F.