[Syrian refugee boys play with stray puppies during snowfall at the refugee camp of Ritsona about 86 kilometers (53 miles) north of Athens, Saturday, Jan. 7, 2017. Over 62,000 refugees and migrants are stranded in Greece after a series of Balkan border closures and an European Union deal with Turkey to stop migrant flows. (AP Photo/Muhammed Muheisen)]COPENHAGEN, Denmark (AP) — Heavy snowfall and below-freezing temperatures continued to sweep the European continent Saturday, causing more than a dozen deaths, grounding airplanes and crippling ferries in Italy and Turkey.