Severe winter weather struck southeastern Europe, with extreme cold and snow in Italy, the Balkans and Turkey. This caused many accidents on roads, school closures, cancelled flights and hardship for the homeless and refugees. The Danube river and Bosporus sea strait were even closed for shipping.
The Royal Netherlands Meteorological Institute (KNMI), which is part of the WMO Regional Climate Center - Network for Europe (WMO Regional Association VI), conducted a rapid analysis into the cold snap from 7 – 11 January 2017.
A high-pressure system moving slowly eastwards over Europe was responsible for bringing cold Siberian air to southeastern Europe along its eastern side. Montenegro, Serbia, the republic of Macedonia and Bulgaria were much colder than normal, with temperatures as low as -15 ºC over five consecutive days. The surrounding countries Italy, Greece, Turkey and Romania were 5 to 10 ºC colder than normal for the time of year. The freezing temperatures with a developing low over the Mediterranean brought large amounts of snow to many places.
This kind of cold outbreak is not unprecedented in this region, they occur on average every 35 years or so, according to the analysis by KNMI in partnership with World Weather Attribution.
This means that every year there is a 3% chance of a cold event like the one of the last few days or colder. The temperature of these cold waves has increased since 1950. This increase is not statistically significant due to the variability of the weather, but climate models show the same increase. Without climate change the cold weather would have been a few degrees colder still, says the KNMI analysis.
The full analysis is hereColdoutbreakinsoutheasternEurope.docx