Most of you had to dream of a white Christmas but as the photo below (taken on Christmas Day)shows, I was lucky enough to have a real one in the French Alps. 
It was taken at the top of Saulire (2738 m), the crossing point between the valleys of Courchevel and Meribel in the extensive skiing area known as the Trois Vallées. The mountains are impressive in any weather but last week, under the influence of a persistent anticyclone, they were truly stunning. The synoptic chart (27.12.07) shows the extent of this High Pressure system which gave us cloudless skies for a whole week
Hopefully you can all recall what you learned about pressure systems last year and can relate the images which follow to the conditions expected in a winter anticyclone
This last one needs a bit of explanation.......
The 'lake' in the valley is, in fact, fog. The descending air of an anticyclone traps cold air in the valleys. Condensation produces the fog which may linger all day if the sun doesn't get high enough to disperse it and on days like this, temperatures are colder in the valleys than at high altitude. This phenomenon is known as temperature inversion as it is the opposite of what you'd normally expect - a decrease in temperature with altitude.
Some days it's almost as if there is a sea of clouds beneath you.......
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I'm sure it won't surprise you to know that I spotted a few glaciated features too.... but they'll keep until tomorrow!!
