Heavy to very heavy rain battered Kerala during the 24 hours ending on Wednesday even ahead of the formation of a low-pressure area over the South-East Arabian Sea, not too far away from its coast, which India Meteorological Department (IMD) expects will become a cyclone by the weekend.
The low-pressure area is expected to concentrate into a depression over the Lakshadweep area and adjoining South-East and East-Central Arabian Sea by Saturday. It may move North-North-West (almost parallel to the West Coast) and intensify further into a cyclone by Sunday and strengthen even further.
Warm Arabian Sea
In the process of doing so, the building storm will drag along humongous clouds and heavy rain with suitably warm southern parts of the Arabian Sea providing it ample supply moisture. Associated southerly to south-westerly winds will blow in some of the showers to Lakshadweep and the country’s South-West coast.
From Friday to Sunday, heavy to very heavy rainfall has been warned off at a few places with isolated extremely heavy falls over Lakshadweep; heavy to very heavy rainfall at a few places over Kerala; and at isolated places over Tamil Nadu and Coastal and South Interior Karnataka.
MJO wave fuels activity
Fishermen are advised not to venture out to the South-East Arabian Sea and adjoining Maldives, the Comorin and Lakshadweep area and Kerala coast from tomorrow (Thursday) morning; over East-Central Arabian Sea and along and off the Karnataka-Goa-Maharashtra-Goa coasts from Friday night. Those who are in the sea have been advised to return to the shore by Wednesday night itself.
The cyclone genesis is the fallout of the arrival over the West Indian Ocean adjoining the South Arabian Sea) of a Madden-Julian Oscillation (MJO) wave which the Australian Bureau of Meteorology categorized as ‘very strong.’ The periodically eastward-moving tropical wave of low pressure, cloud and rain is always known for setting up regional monsoon onsets, low-pressure areas, and cyclones.
May weaken over Bay of Bengal
The wave moved across the African and West Indian longitudes last week and is currently located over the Central Indian Ocean (around Sri Lanka) at moderate strength. Global models generally agree that MJO move will continue to move over the East Indian Ocean (South Bay of Bengal) while weakening.
Meanwhile, the Chennai Meteorological Centre listed stations receiving heavy rain (above 5 cm) on Tuesday as Thiruvananthapuram City-16; Kayamkulam-15; Konni-12; Kanjirappally-11; Neyyattinkara-10; Punalur-9; Agathi (Lakshadweep), Varkala and Ponnani-8 each; Thiruvananthapuram Airport-7; Kollam and Haripad-6 each; Kozhikode, Vaikom, Thodupuzha and Kuppady-5 each.
Rainfall occurred at most places over the Lakshadweep area, Coastal Andhra Pradesh, Yanam; at many places over South Interior Karnataka and Rayalaseema; at a few places over and Coastal Karnataka and Telangana; and at isolated places over Tamil Nadu and North Interior Karnataka on Tuesday.