Monsoon onset over Kerala likely on May 27, says IMD

MONSOON NORMALLY MAKES ONSET OVER THE SOUTHERN STATE ON JUNE 1

HT Correspondent

NEW DELHI: Monsoon onset over Kerala is likely to be on May 27, five days ahead of its expected onset, India Meteorological Department (IMD) said on Friday. It left a model error of ±4 days in the forecast.

Monsoon normally makes onset over Kerala on June 1. Initial monsoon rains are experienced over the south Andaman Sea and the monsoon winds then advance north-westwards across the Bay of Bengal.

“This year, the onset of southwest monsoon over Kerala is likely to be earlier than normal date of onset. As per the normal dates of monsoon onset/ progress, the southwest monsoon advances over the Andaman Sea around 22nd May. In association with enhanced crossequatorial winds, conditions are becoming favorable for the advance of Southwest Monsoon into the South Andaman Sea, Nicobar Islands and some parts of southeast Bay of Bengal, around May 15,” IMD said in a statement.

According to private weather forecasting company Skymet Weather, Monsoon is likely to arrive over Kerala on May 26.

In April, Skymet had also forecast that the upcoming monsoon season will be ‘normal’ to the tune of 98% (with an error margin of +/- 5%) of the long period average (LPA).

“Skymet expects the onset to be earlier than the normal date. Based on the data from 1961 to 2019, the normal date of onset over the Indian mainland is June 1. The onset of the Southwest Monsoon over Kerala is chiefly controlled by oceanic conditions, both in the Arabian Sea and Bay of Bengal. Recent cyclone Asani enabled the monsoon stream to lock in over the Bay of Bengal, earlier than normal,” Skymet said in a statement on Friday.

The combined influence has wiped away the anti-cyclone over the central parts of the Arabian Sea, an essential condition for ingress of monsoon surge. This will also be assisted by the MJO (Madden Julian Oscillation) entering the Indian Ocean, albeit with low amplitude. Pre-monsoon showers will be extensive and powerful over Kerala. Skymet predicts that this year, the onset of southwest monsoon over Kerala is likely to be on 26 May 2022 with a model error of +/- 3 days,” the statement added.

MJO is a band of rain clouds that moves eastwards over the tropics and is responsible for most weather variations in the region – including the Southwest and Northeast monsoons.

“It’s been raining in the South Andaman region. We expect the monsoon to reach the South Andaman region around May 15-16. Over Kerala also, pre-monsoon activity has started. The south peninsular region has received good rainfall because of Asani,” said Mahesh Palawat, vice president, Skymet Weather.