On record to be the driest December in these parts ever. Almost no rain, and no snow this month. (In 2008 around this time, we had a record snowfall, a foot on the ground at Steve's house. Gotta love Oregon weather.)
Which is not to say we don't have water in the air. The last couple weeks, we've had fog, hanging on all day some days, and on nights like last evening, it has gotten cold enough so the fog has frozen.
I used to wonder, how was it possible to have fog when the temperature was below freezing? Why didn't it just, you know, freeze and fall out the sky?
Same reason running water doesn't go solid as fast as standing water–that motion, heat, all like that.
However, when the things around you are below freezing–roofs, trees, sidewalks, spider webs–then the fog does coat that in a nice layer of rime.
So one could easily have a white Christmas without any snow ...