Hello,

you subtract the surface sea level pressure of the Novembers before the 10 mildest Decembers (January / February months) from the Novembers before the 10 coldest Decembers (January / February months) since 1987. You get the areas of the greatest differences between the two groups, what you can see below are the charts leading to a cold month, just the opposite leads to a mild month in South Eastern Europe (defined as 37.5 – 45°N 17.5 – 30°E).

Novembers before a cold / mild December:

Novembers before a cold / mild January:

Novembers before a cold / mild February:

Yours

KHB