Hazy about untimely fog that caused blackouts
a large part of northern India, including capital Delhi, went powerless due to tripping of transmission lines of the Northern Grid. It first happened on March 8 and then on March 10, resulting in large-scale blackouts and affecting the Northern Railways network. The reason: dense fog, unusual for March.
Tripping of transmission lines is not a new phenomenon. It happens almost every year during peak winters