Monsoon officially ends on record high

The southwest monsoon season officially ended on Monday, with Maharashtra recording 32% excess rainfall, the fourth-most excessive seasonal rain since the India Meteorological Department (IMD) started keeping records in 1901.

Historically, the state had recorded the highest excessive rainfall at 37.6% above its average levels in 1988.

Despite a 15-day delay in the monsoon onset, Mumbai witnessed one of its wettest monsoons in history.

Between June 1 and September 30, Mumbai (represented by the Santacruz weather station) received 66% (1464.4mm) excess rainfall with 3,670.2mm rain as against the seasonal average of 2,205.8mm.

South Mumbai recorded 35% excess rain with 2,734.8mm rain against the average of 2,021.4mm. Excess rain was also recorded at Palghar (3,883.4mm) and Thane (4,084mm).

Maharashtra recorded 32% excess for the season – 1,328mm as against the of 1,004.2mm. Pune recorded 109% excess rainfall – 1,803.5mm as against its of 861.5mm.

Central Maharashtra, Vidarbha and Konkan recorded 55%, 12% and 32% excess rain this season. Marathwada was the only subdivision that recorded 12% deficient rainfall.

DS Pai, head of climate research and services at IMD Pune, said the effects of El Nino – a phenomenon caused when warm water from the western Pacific Ocean flows towards the east – became neutral in the second half of the monsoon and a positive Indian Ocean dipole (IOD) revived the monsoon.

A positive IOD is associated with high rainfall during the monsoon.

“Added to the above global and regional weather phenomena, numerous low-pressure areas that formed over the Bay of Bengal moved from Odisha coast to Gujarat and even Rajasthan. These low-pressure systems kept the monsoon trough almost across central India including Maharashtra,” said Pai.

The weather bureau said the withdrawal in northwest India should start in the next five days.