Southwest monsoon likely to hit Kerala on May 31: IMD

The monsoon onset over Kerala marks the beginning of the four-month long chief monsoon season over India. The country receives over 70 per cent of its annual rainfall during the June-September period. Rainfall during these months replenish the reservoir stocks, groundwater reserves and are vital for rain-fed kharif cultivation in the country.

Quantitatively, rainfall is expected to be 106 per cent of the Long Period Average (880mm as per 1971 – 2020 data).

This year, the Met department has forecast ‘above’ normal rainfall over the country during the upcoming season. Quantitatively, it is expected to be 106 per cent of the Long Period Average (880mm as per 1971 – 2020 data).

Earlier this week, the IMD had said that the monsoon advance over the south Andaman Sea, Nicobar islands and parts of Bay of Bengal was expected around May 19, which is approximately two days ahead of the normal date for this region.

Satellite images from over the past few days have shown cloud bands reorganising themselves along the equator. This cloud band is known as the Inter Tropical Convergence Zone (ITCZ), which is crucial for bringing rainfall over the country. During the southwest monsoon season, the ITCZ shifts north or southward along India and influences the winds that bring rainfall over the country.

In the past one decade, the realised monsoon onset over Kerala was marked in May during 2017, 2018 and 2022.