Though the chances for snow are slight, Christmas is still far enough away, that conditions could change. According to Gebauer, “In 2009 the weather in Germany was determined by a high pressure area during the first half of December, but then the low pressure zone Uwe moved in from the north and provided a blanket of snow that, despite a slight thaw on Christmas Eve, lasted until Christmas Day.”
What Petra Gebauer says is more like to occur, is something similar to the developments in 2007, when the high-pressure system Bernhilde dominated the weather for 22 days in Germany starting December 11. In Berlin it was mostly foggy, cold, and damp, and though a few snowflakes were spotted just before Christmas Eve, there was no snow cover throughout December.
In any case, a white Christmas is an exception in Germany, at least in Berlin, according to Gebauer. In 74 percent of all the years since weather records were started in Berlin-Dahlem in 1908, everything remained green.
Meteorologists say Christmas is "white" if there is a snow cover of at least one centimeter on two of the three Christmas holidays. For precipitation to form, moist air is needed that is transported by low-pressure systems from the south, west, or northwest. The biting cold from Siberia is too dry for snow to form. Freezing temperatures are, however, required for the precipitation to fall as snow. A few degrees below freezing are favorable. And once the snow is there it needs to remain cold for a white Christmas.
The meteorologists of Freie Universität Berlin will still be selling weather sponsorships for Central European high and low pressure zones, until Friday, December 20. The proceeds are used to support teaching and research, in particular the weather observation by students at the Institute of Meteorology. In 2014 the high-pressure zones will be given male names and the low-pressure zones will be given female names. The highs cost 299 euros and the lows cost 199 euros, plus value-added tax. The weather observation series in Dahlem has been running for more than 100 years, making it one of the longest climate records worldwide.
More information and interview opportunities about the weather at Christmas
Meteorologist on duty at the Berliner Wetterkarte e. V., Institute of Meteorology, Freie Universität Berlin, Tel.: +49 30 838-71212 (7 days/week; phone calls only answered between 9-12 a.m. and 2-4 p.m.); Email: firstname.lastname@example.org
More information about the weather highs and lows
- Julia Sieland, Daniela Schoster, Institute of Meteorology, Freie Universität Berlin, Tel.: +49 30 838-71226 , Email: email@example.com
- Petra Grasse, Thomas Dümmel, Institute of Meteorology, Freie Universität Berlin, Tel.: +49 30 838-71222