You are in Maine, thanks for providing that information, it helps. Based on that alone I'd say yes, they will need more room this winter.
I did not say you needed a bigger coop, I said they will need more room. Chickens don't know the difference in coop space, run space, or free range space. They just know they have it when they need it, wherever it may be. I try to look at their "space system" instead of breaking it into individual components. It's up to you to manage them in a way that they have access when they need it.
That looks like an elevated coop. Did a run section come with that? If so how big? That may help determine if that is enough room this summer. If it has anything you should be OK for the summer. You can follow the link in my signature below to get my thoughts on why space is important. I don't believe in magic numbers as to how much square feet you need in the coop or run, we all have different circumstances, like your climate. But in general I find the tighter I pack them the more behavioral problems I have to deal with, the harder I have to work, and the less flexibility I have to deal with issues.
Chickens hate change. If a chicken wakes up to a white world after an overnight snow they probably aren't going to go out in it for a few days, pretty much locked in the coop. Run space is not available. Also, mine go out when the temperature is below 0* F as long as it's calm. I don't see much below 0* F so I don't know what that limit is. But if cold wind is blowing on them mine are not out there. A nice breeze is comfortable in a hot summer but a cold wind is "not no how, not no way, I ain't going out there" in winter.
If you can provide space outside that remains snow-free in winter and provides good wind protection, you will probably be OK. Some people count on shoveling out their run when it snows but that's not always easy when a blizzard is blowing. You might be able to cover you run in a way that keeps snow and cold winds out. Some people use heavy plastic like a tarp. In a way the run becomes part of the coop in winter.
If you do try to enlarge that coop instead of providing more usable area outside, I'd at least double it in size. If it is an elevated coop that probably will not be easy since you need to be able to reach all inside areas.