A police officer is on duty amid snowfall in Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, Nov. 19, 2019. Days of continuous snowfall has left streets wet and slippery in the city of Urumqi. (Xinhua/Wang Fei)

A police officer guides traffic amid snowfall in Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, Nov. 19, 2019. Days of continuous snowfall has left streets wet and slippery in the city of Urumqi. (Xinhua/Wang Fei)

A police officer is on duty amid snowfall in Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, Nov. 19, 2019. Days of continuous snowfall has left streets wet and slippery in the city of Urumqi. (Xinhua/Wang Fei)

A police officer guides traffic amid snowfall in Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, Nov. 19, 2019. Days of continuous snowfall has left streets wet and slippery in the city of Urumqi. (Xinhua/Wang Fei)

A police officer guides traffic amid snowfall in Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, Nov. 19, 2019. Days of continuous snowfall has left streets wet and slippery in the city of Urumqi. (Xinhua/Wang Fei)

A police officer pours cinders on a street to make it less slippery amid snowfall in Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, Nov. 19, 2019. Days of continuous snowfall has left streets wet and slippery in the city of Urumqi. (Xinhua/Wang Fei)