After unusually mild weather in December 2011 and early January 2012 almost all over Europe, the weather situation changed abruptly in the second half of January. An incursion of cold polar air, coming from northern Russia at the south flank of an extensive high pressure area brought a sudden cooling to almost the whole Eurasian continent). During that cold spell, also some considerable snowfall occurred over various parts of the continent. In the first half of February, the cold wave started weakening first in Asia and in mid-February also in Europe.