The cold spell, nicknamed "the Beast from the East" in the UK, is carrying freezing winds across the continent, and temperatures as low as -30C.
At least seven people have been reported dead since Monday - five in Poland and two in Romania.
The International Committee of the Red Cross has appealed to the public to check on at-risk neighbours.
"Just knocking on someone's door to check they have everything they need can make a huge difference," the ICRC's Europe director, Simon Missiri, said. "It could even be the difference between life and death."
Red Cross emergency teams have opened shelters and are providing hot food and blankets for thousands of people across the Continent, it said.
Following are several scenes from the snow blanketed Europe.
(Story and Pics : BBC News)
The flurry left London's Green Park under a blanket of snow
The ruins of Pompeii - near Naples in southern Italy - were covered with snow
The Coliseum in Rome was blanketed in snow for the first time in years on Monday
In north-eastern Germany, the port of Kirchdorf saw boats trapped by the ice
Heavy snow hit Casaglia, Italy, on Tuesday
Trucks and cars abandoned after a pile-up in Sjobo, Sweden