India Met Department (IMD) has pushed the date of monsoon over Kerala by two days to around June 8 (Saturday), but falling within the larger onset window initially predicted by it.
Conditions are also likely to become favourable for its advance into some parts of the North-Eastern States during the following four days, the IMD said this (Thursday) morning.
Strong onset seen
The monsoon has also advanced into some more parts of the south Arabian Sea, most parts of the Maldives-Comorin area, and some more parts of southwest Bay of Bengal.
This happened with the strengthening and deepening of the cross-equatorial monsoon flows and an east-west shear zone of wind turbulence developing across the South Arabian Sea and the Maldives-Comorin area.
A forecast for Saturday said heavy rainfall is likely at isolated places likely over Kerala, Mahe, Lakshadweep, south interior Karnataka, plains of Bengal, Nagaland, Manipur, Mizoram and Tripura.
A trough of lower pressure lies over the southeast Arabian Sea off Kerala-Karnataka coasts. This is gradually expected to intensify into a depression/cyclone, but keep its track initially along the coast.
This gradually strengthening system would help hold the monsoon in good shape as it propagates over land along the coast and into the adjoining interior.
Squally weather with winds with speeds reaching up to 45 km/hr is likely to prevail over the southwest Arabian Sea off Somalia Coast as well as the Maldives-Comorin area. These are two the areas where stormy conditions are expected to develop over the next few days.
The IMD has warned that fishermen should not venture into the seas.
Widespread rain forecast
The forecast for Sunday said squally weather would continue over both off the Somali coast as well as the Maldives-Comorin area with wind speeds reaching up to 45 km/hr.
As for Monday, heavy rainfall is forecast over Kerala, Mahe, Lakshadweep, South Interior Karnataka, Tamil Nadu, Puducherry, Karaikal and the North-Eastern States.
Once again, squally weather with winds, speed reaching 45 km/hr may prevail off the Somalia Coast and Maldives-Comorin area. Fishermen are advised not to venture into these areas.
On Thursday morning, the northern limit of monsoon passes through Katunayake (Sri Lanka) and into the adjoining South-West and South-East Bay.
The east-west shear zone runs roughly across Maldives-Comorin area. It is very likely to shift northwards gradually leading to favourable conditions for onset of the monsoon over Kerala.
Extended forecast for three days from June 11 to 13 said widespread rain would lash parts of East, North-East and the South Peninsula India and the Andaman & Nicobar Islands.
Isolated heavy falls are likely over Tamil Nadu, Kerala, Lakshadweep, Andaman & Nicobar Islands and the North-Eastern States while it would be isolated to scattered over the hills of the Himalayas.