Istanbul's seven peaks were covered in a thick blanket of snow and the city heard the rumble of thundersnow after a second day of what Turkish weather presenters are calling a "Siberian storm front."

Intermittent squalls pushed through the city Tuesday and intensified Wednesday, testing unprepared drivers as they tried to navigate the slick, steep roads without snow tires.

Istanbul Mayor Kadir Topbas told reporters that city crews had laid 15,000 tonnes of salt across the city — more than ever before. It wasn't enough. Officials reported more than 800 crashes, and urged drivers in the city of more than 15 million to stay off the roads and take public transit.

Turkish media showed video of hundreds having to abandon transit and make their way to their destinations on foot due to the traffic standstill.

A commute that normally takes 45 minutes took 4½ hours, one man told CBC News.

At least two deaths were reported in cities in Turkey's Black Sea region due to exposure to the cold.

Another death — a stabbing during the storm — stunned many in Istanbul.

Journalist Nuh Köklü was having a snowball fight with several friends Tuesday when a shopkeeper nearby allegedly threatened the group, attacking them with a knife after a snowball hit his window.

Köklü, 46, was stabbed in the heart and died in hospital.

Air Canada flight diverted

Turkey's main airport, Atatürk International, was essentially shut down for three hours Wednesday morning, the conditions making it impossible for flights to take off or land.

An Air Canada flight from Toronto to Istanbul was diverted after circling several times. Air Canada spokesperson Peter Fitzgerald told CBC News "two attempts were made [to land] and then the decision was taken to divert to Athens."

Many in the city tried to enjoy the novelty of the storm. Though Istanbul is not a stranger to snow, the strength and duration of this storm system is unusual.

A father brought his two sons outdoors in Istanbul's Gümüssuyu district near Taksim Square. As the boys started a snowball fight, he said, "Enjoy it while you can! You won't see this kind of weather for years."