Misty Days Before Christmas
After the storm on December 5, 2013, a high pressure system led again to quiet but grey days in Berlin with many hours of mist as before the storm. Sunlight became very rare during the following days till December 14. Only in some areas the mist retreated for some hours. These conditions are not the kind of weather photographers and video-makers are looking for. Some people head for the mountains where they could look at the mist from above and where they often find an impressing atmosphere. From the tops of the mountains the mist looks like the sea. This happens when air at the ground is cold and there are layers of warm air on top of the pool of cold air which work like a cap. The air below is trapped. Of course the quality of the air below the cap in not very good, particularly in areas with a lot of emissions. Nevertheless there is something about even these grey days where you couldn’t see very far (and if you don’t have a chance to go to the mountains). In the city before Christmas countless lights used for decoration at Christmas markets can create very interesting effects. The mist reflects the lights and it is astonishing how bright the city looks at night. If you spend some time you will find that mist can be very different and it changes constantly. Sometimes it seems that thick white clouds are close to the ground, then it becomes more clear and the layers of clouds are more around the skyscrapers. It’s further remarkable that at a certain high there can still be wind. Of course it’s very chilly with temperatures not far from zero. If the temperatures drop further below zero conditions can became very dangerous and these weather condition is often responsible for car accidents particularly on the countryside where streets close to a river for example can become wet and slippery with a sheet of ice. It also depends on the amount of humidity in the air. Outside Berlin there were droplets of water falling from the trees as if it would be raining (which wasn’t the case). It’s a bit like if you have too much humidity in your bathroom and droplets appear on cold metal.
So many days in December with mist are indeed a bit unusual since we might expect snow or windy days before Christmas in Middle Europe. Usually long lasting high-pressure systems appear more often in January here. However weather is always unique and it might be much too early to speak of an anomaly here. Nevertheless the increasing numbers of extreme conditions and new weather patterns over the last years make steady improvements in weather and climate research more and more important.
http://youtu.be/P9xTNwMnq4Y