India, May 25 -- The southwest monsoon made onset over Kerala on Friday, arriving eight days before its normal June 1 date and marking the earliest arrival since 2009, the India Meteorological Department (IMD) announced.

The May 24 onset is in line with IMD's prediction of May 27 arrival and represents the fifth earliest monsoon onset in the last 55 years. The earliest recorded onset was May 18 in 1990.

"During monsoon onset we sometimes see low pressure systems develop which turn into depression. A depression has developed and monsoon has strengthened, all the criteria for monsoon onset are fully satisfied now. Large scale processes such as cross equatorial flow are also met. Monsoon will cover some more areas in the next 2-3 days," sa...