[ Rather predictably so, Data has taken a far more active interest in the holiday and the ways in which it is being observed. He's certainly familiar with it - in the way he's familiar with many human cultural traditions that were more dominant centuries prior to his creation. Seeing it in practice, observing those who do regularly celebrate it, and having the option to participate in the festivities himself - that is a far different matter than merely perusing the files he has stored on the topic in his memory banks. Certainly that curiosity is not mutually exclusive with an interest in the weather regulation. If anything can be said of Data's curiosity, it is that its scope is hardly limited.
So, naturally, he's out as well, wearing his standard uniform. While his sensory input informs him of the precise temperature drop in the dome, of course he does not feel cold. Needless to say, he approaches Seven as soon as he comes across her - and knowing as much as he does about the Borg, is not surprised to see her bundled up. (Actually, he's still concerned that she may be cold.) A tiny smile is in place as he approaches her. ]
It would seem the wardens do not care for simulating a more natural transition of seasons.