Is it just me, but 20-degree Arctic air (or air at any other temperature) seems colder than regular 20-degree air?
Arctic air of a given temperature in the winter season might “feel” colder to you than air of the same temperature but of different air-mass origin, but you realize that it’s only an apparent feeling. Twenty-degree air is 20-degree air, regardless of its origin. Other factors (such as wind speed, whether it’s day or night, the amount of cloudiness, etc.) all play a role as well. And what of the person who does not know about the origin of the air mass?
A factor of greater importance is acclimation. A high temperature of 65 degrees in January, when we’re used to much lower readings, will feel mild or even warm, but the same daytime reading in July, when we are acclimated to temperatures in the 70s or 80s, or higher, will feel chilly.