Answering one of the most frequently-asked Severance fan questions: Why is it always winter?

Fans of Apple TV+’s Severance have spent two seasons now dissecting every eerie detail of the show. Why is all the tech so retro? What year is the story even set in (a point that I've previously explored here)? What do the numbers mean, and what’s Lumon actually up to? But one of the most persistent fan questions has nothing to do with Lumon’s cryptic corporate culture or the mysterious goings-on in the break room.

The question I'm referring to is actually much simpler: Why is it always winter on the show?