How did India's monsoon produce a disaster?

There are usually celebrations in India when the monsoon rains arrive. The rainy season is the backbone to the economy, nourishing rivers and farms as well as breaking the stifling heat of the summer months. However, this year, the monsoon rains brought destruction and tragedy. The monsoon officially arrived in India on June 16, two-weeks earlier than expected. In fact, this was the earliest recorded arrival since records began in 1960. And, this year the monsoons came with “unexpected vigour”. The most affected area was the Himalayan state of Uttarakhand, where its capital Dehradun recorded 601mm of rainfall in just 60 hours, and large-scale flash floods and landslides followed.