India Met Department (IMD) has taken note of the ‘rogue’ circulation in West-central Arabian Sea, off the Oman coast, which has developed into a low-pressure area.
Proximity to land does not give much scope for its intensification, which is a good augury from the viewpoint of onset of South-West monsoon over Kerala.Any intensification could potentially siphon away moisture from the monsoon system now beginning to build over the Arabian Sea and weaken it.
The Met Department located the ‘low’ would move northwestwards (towards Yemen-Oman) during the next two days. Meanwhile, it said conditions were favourable for further advance of the monsoon over some parts of south-east Arabian Sea and Comorin area (just off Kerala) during next three days. By this time, the rogue ‘low’ and its influence over the monsoon system would have died out, setting the stage clear for the onset over the Kerala coast.
Some more parts of Bay of Bengal are expected to be brought under monsoon cover during this period.One other good augury for the monsoon came in from the Bay of Bengal, where a persisting cyclonic circulation is to deepen into a ‘low.’
The Met Department located the cyclonic circulation to over west-central and adjoining north-west Bay Bengal, an area thought ideal for formation of monsoon ‘low’s. Satellite imagery on Monday showed convective (rain-bearing) clouds standing tall over North Tamil Nadu, Bay of Bengal, Andaman Sea and south-east and west-central Arabian Sea.
Meanwhile, in north-west India, heat wave conditions have abated after a western disturbance with its cooler winds descended over the region.
HEAT RELENTS
Winds blow in from high-pressure area to low-pressure area, so heating of the plains of north-west is inevitable for building the temperature and pressure differential relative to the South India. This pressure differential allows monsoon winds from Kerala to race into North along the Western Ghats into Karnataka and Maharashtra before converging with monsoon easterly winds from Bay of Bengal.
Rainfall would scale up along the West Coast from Thursday, the Met Department said.