During a winter cold wave such as the present one, it becomes easy for people to toss out lines such as, "Where's your global warming now?" or, "We could use a little global warming today!" However, statements such as these actually demonstrate a lack of knowledge about our climate.
In fact, cold snaps like the present one in our region are happening much less frequently than a few decades ago. One of the reasons the present cold spell feels unusually cold is that the past four winters have all been remarkably mild. Even as the climate of the Arctic region warms significantly, it still gets very cold in up there in winter; and when Arctic air is displaced southward, it still feels very cold to us.
Even this year, very mild weather the first half of January will greatly offset the present cold weather and keep this month from being statically cold.