Explanation:

Weather associated with Western Disturbances

The arrival of western disturbances causes precipitation leading to an abrupt decrease in air temperature over whole North-West India.
The weather becomes clear after the western disturbances passes away. Also possibility of foggy conditions.
Western Disturbances also bring heavy snowfall in the Himalayan Region and a cold wave to north Indian plains.

Third statement is incorrect as it should read as Cold wave during the disturbances.