The mild winter of 2007: what were the causes?

The meteorological winter of 2007 (December 2006, January and February 2007) had an average temperature of 6,6°C in De Bilt, the Netherlands. This makes it the mildest winter since regular temperature observations were started in The Netherlands in 1706. The normal winter temperature is 3,3°C (1971-2000 average). This winter is 0,6°C warmer than the previous record holder, 1990, and more than one degree warmer than the mildest winter in 1706-1900 (1737, 5,3°C). Since summer last year there has been a spate of warm records and autumn 2006 was by far the warmest on record in large parts of Europe. The predominantly southwesterly flow and global warming appear to explain most of the extraordinarily warm temperatures. These factors may even be interconnected.