The North-East monsoon will settle over the South Peninsula around Friday, October 26, late by a week, says the India Met Department (IMD). This followed its formal announcement about the predecessor South-West monsoon having withdrawn from the entire country on Sunday.
Rain lashes South
The North-East monsoon can commence only after its predecessor has exited the country. Even after this, there is going to be a slight delay which is attributed to some ‘extra-territorial’ reasons. The reference is mainly to the high-pressure area that sits above the Asian latitudes and which guides the monsoon in reverse. This is expected to sort itself out over the next few days.
This has not affected the pattern of rainfall pattern with moderate to heavy showers being reported from many parts of the South Peninsula over the past few days. The 24 hours ending on Sunday morning saw rains lash most places over Kerala, at a few places over Tamil Nadu, the Lakshadweep area and Coastal Karnataka, and at isolated places over South Interior Karnataka.
Among stations recording heavy to very heavy rain (in cm) included Virudhunagar-12; Peraiyur and Nanguneri-9; Aranmanaipudur and Periyakulam-7 each (all Tamil Nadu). Heavy rain as also thunderstorms and associated lightning and gusty winds have been forecast for Tamil Nadu, Puducherry and Kerala on Sunday and Monday.
What is driving the violent weather here is the presence of a cyclonic circulation over South-West Bay of Bengal off Tamil Nadu-Sri Lanka coasts with a trough extending to Lakshadweep. Another trough links Maldives with South Interior Karnataka in close proximity, rounded off by a circulation over Maldives-Lakshadweep. These are all signs of the South Peninsula bracing itself to receive the North-East monsoon.
‘Low’ off Myanmar
Meanwhile, true to forecasts, a low-pressure area had formed over Gulf of Thailand (Siam) and moved towards North Andaman Sea on Saturday, with the tail straddling the North Andaman Sea and adjoining Myanmar as seen on Sunday.
According to the IMD, it may become ‘more marked’ by Monday, signalling intensification. The Myanmar Department of Meteorology and Hydrology has maintained a watch for a depression here. According to the latter, the system may cross the the deltaic areas of Myanmar, and not head into the open waters of the Bay. Almost all international weather models are in agreement with this view.