The India Met Department (IMD) has indicated that the monsoon is bracing for another revival phase in the South Peninsula and Central India from July 6 and 8 respectively. This would come about with the likely formation of a cyclonic circulation over the North-West Bay of Bengal and the adjoining Bengal coast around Friday (July 6).
MONSOON ‘ANCHOR’
This circulation is just the mechanism needed to 'anchor' the all-important monsoon trough that is currently displaced, leading to weak rain conditions over Central and adjoining Peninsular India.
The circulation would help pull back the trough and anchor its southern end in the Bay waters, from where it would act as a motor pump to 'lift' moisture wafting in the Bay.
This moisture would be routed through the rest of the trough along its west-north-west alignment, to bring rain to the South (including Central and adjoining Peninsular India).
The trough, currently displaced farther north along the foothills of the Himalayas, can only serve the northern parts of North-West and East India, including Uttar Pradesh and Bihar.
IMD now expects that the circulation would help align the trough closer to its normal position from Saturday (July 7) to preside over another revival phase of the monsoon.
Consequent changes in the flow pattern are likely to cause an increase in rainfall over Karnataka, Maharashtra, Telangana and Andhra Pradesh from Friday and over Central India from Sunday.
OFFSHORE TROUGH
As if in anticipation, the southern end of the offshore trough, the important feature in the South, has shifted its moorings back from Lakshadweep to Kerala, where it belongs.
Full-blown monsoon conditions require that this trough lie extended from South Gujarat all the way down to Kerala. Today's alignment from North Maharashtra to North Kerala makes up just half of it. The situation may improve from the weekend, when rains are forecast to escalate in near onset-phase fashion from the South and into the adjoining interior.
Meanwhile, the 24 hours ending Tuesday morning saw heavy to very heavy rain over Himachal Pradesh, Arunachal Pradesh, Assam, Meghalaya as well as Konkan and Goa. It was heavy over Punjab, North Haryana, coastal Karnataka, Tamil Nadu, Puducherry, Gujarat, the hills of Bengal and Sikkim.
Satellite maps this afternoon showed the East Coast getting more distributed rain than the West Coast, due mainly to a cyclonic circulation off the North Andhra Pradesh and South Odisha coasts. This could well be the 'host' that would secure the southern end of the West-East trough over land in the North and propel the monsoon revival from the weekend.