More counterexamples.
I had the opportunity to live in Sofia, Bulgaria for 6 weeks, and I’ve visited the places they are discussing here.
“The last time the sea in the Bulgarian resort of Burgas was covered with ice was in 1954. Throughout the entire 20th century ice paralyzed this part of the Black Sea area only 3 times.”
The Balkan country is experiencing extreme cold. In some areas, the air temperature dropped to -29 C (-20 F).
“This winter is strong for many countries in Europe. In Italy, the famous Roman fountains display a frozen waterfall, it is snowing in Montenegro, and in Belgium the rails of the train have frozen.