I live about 30 miles from MB SC in NC ( North of MB ). We don't get a lot of really cold weather here but not unusual for lows below freezing in Jan / Feb. Lowest temp so far this Winter has been around 28-30f, but we are right on the barrier island. Move inland 30 miles or so and freezing temps are pretty common. I have a renter from Cleveland area and he says it never gets cold here, so it it all relative!
As someone suggested, look at the stats. We were 70f a week or so ( actually about 70 yesterday but raining ) Bottom line is it does get cold ( by our standards :) ) but not very cold. It does not last long either. Cold one week, warm the next. Just looked our 10 day forecast lows range from 25-50f and highs from 46-62f. That is for Wilmington, it would be a few degrees warmer on the beaches, and in MB.
There are some people who winter here, more so in MB, a little further south. We bought our TT last Feb and took it to MB for a couple days shake down cruise. More people wintering there than I expected.
We rarely get snow anymore here, although we did have a trace in Nov this year, which is very unusual. I have seen 12-14inches of snow here on the beach, but that was 25 years ago and very very unusual.
I usually try to leave for a while in Jan / Feb cause I can and it's just boring sitting inside so much. My daughter and family are in Jax Fl and it is quite a bit warmer there (400miles south of here) than here. To get what I would call consistent warm weather in Winter go to mid Fl or below.