Days are short and nights are long and dark. Here in southern Finland (Helsinki area), we get about 5ish hours a day of daylight, but in Lapland in northern Finland, the sun never rises! On top of that, even when it is daylight, most of the time the sun doesn't shine.
Of course, one beautiful thing about wintry Finland is the snow. It makes the night seem a little brighter. Plus, I'd rather see clean white snow on the ground than yucky mud because it rains a lot.
Being from a state in the US where we get more sunlight, warmer temps, and almost no snow, winter is specially rough on me. I've even spoken to some native Finns who struggle during the winter. And they've lived here their whole lives!
After spending the previous winter in Finland and am now in the middle of another, I've developed a few rule of thumb for handling the winter weather and the blues that sometimes come with it.