I only saw this when changing the payload screen. It mainly reverts the plane back to cold and dark if I change anything there and press ok. For normal menu stuff, she remains intact but I never tried anything on the weather as this comes in via addons.

So I can confirm that some menu changes cause the cold plane. The workaround is to set everything up (weather, payload, fuel) right after loading and then start running through the checklists and things.