mumbai

Updated: Jun 16, 2019 00:53 IST

Light to moderate showers continued in the city for the fourth consecutive day but there is still some confusion over the onset of the south-west monsoon over Mumbai and the rest of the Konkan coast.

The India Meteorological Department (IMD) said it is likely to announce the onset of the south-west monsoon over south Konkan and Goa by Tuesday (June 18) or even a day before, depending on the progress of the monsoon currents.

“Rains over Mumbai and surrounding areas continue under the influence of Cyclone Vayu, which is currently 355km west-southwest off the Porbandar coast of Gujarat. The progress of the monsoon was delayed due to the presence of this weather system and Mumbai continues to receive pre-monsoon showers,” said Bishwambhar Singh, director, regional meteorological centre, IMD, Mumbai. “However, there might be rapid progress in monsoon currents over the next 72 hours, allowing the onset over Maharashtra,” he added.

There is some debate, however, over IMD’s forecast. One independent weather expert believes the current weather pattern indicates that the south-west monsoon is already here.

“As of June 15 afternoon, tropical Cyclone Vayu was over 600km away from Mumbai. This is a very large distance to produce any direct rainfall over the city and coastal Maharashtra,” said Akshay Deoras, meteorologist and PhD researcher at the department of meteorology, University of Reading, UK.

“This cyclone helped the progression of monsoon along the coastal parts of the state. As indicated by the Doppler radar at Mumbai, the city is witnessing winds from the south-western direction near surface levels, and from the eastern direction at higher altitudes. This rainfall pattern clearly indicates the arrival of monsoon,” said Deoras.

He added that a similar situation had occurred in June 2014 due to tropical Cyclone Nanauk. “At the time, the wind pattern over Mumbai and coastal Maharashtra was similar to the current condition. The arrival of the monsoon in 2014 was declared around mid-June, so delay to declare the onset is questionable,” he said.

Private weather forecasting agency Skymet said weather factors were indicative of south-west monsoon conditions but the comparative scenario needs to be studied further to declare onset. “Currently, south-westerly winds moving anticlockwise under the influence of Cyclone Vayu are bringing rains over Mumbai, the rest of the Konkan coast and Goa. However, once the intensity of this weather system reduces completely from Sunday, rainfall activity is likely to reduce, indicating how the monsoon currents along the west coast will move northwards. It is expected to enter Maharashtra by June 18, and remaining areas of the state by June 21,” said Mahesh Palawat, vice-president (meteorology and climate change), Skymet.