As very severe cyclone ‘Hikaa’ heads for a landfall over Oman later tonight (Tuesday), focus of weathermen will shift back to a cyclonic circulation that has crossed into South Andhra Pradesh coast from the Bay of Bengal.

This circulation would be the fulcrum of monsoon activity as its moves in a typcical West-North-West track over land, and brings in a fresh rain spell over many parts of Peninsular India.

‘Heavy’ to ‘very heavy’ spells

India Met Department (IMD) has forecast fairly widespread to widespread rain with isolated heavy to very heavy rainfall, mainly over Tamil Nadu and Puducherry, over the next two days.

A similar outlook is given for Rayalaseema, Telangana and Coastal Andhra Pradesh through Tuesday; over Kerala and South Interior Karnataka on Wednesday; and over Konkan and Goa on Thursday.

The 24 hours ending Tuesday morning saw heavy to very heavy rainfall in Madhya Pradesh, Marathawada, Assam and Meghalaya while it was heavy over Madhya Maharashtra, Bengal, Sikkim, Odisha, Jharkhand, Uttar Pradesh, Telangana, Rayalaseema, Interior Karnataka, Kerala and Tamil Nadu.

Cyclonic circulations

Meanwhile, on Tuesday, the Australian Bureau of Meteorology said the development of the very severe cyclone ‘Hikaa’ could indicate that the withdrawal of the annual Indian monsoon is around the corner.

The withdrawal should normally start on September 1 from North-West India but lasted almost a month more thanks to the extended run of the monsoon.

In fact, on Tuesday, a cyclonic circulation each was perched over South-West Rajasthan, East Rajasthan and adjoining West Madhya Pradesh where a rain-suppressing anticyclonic circulation should be present.

 

Seasonal peaks

This also brought a portion of the trough to lie over the Arabian Sea, which facilitated the development of the tropical cyclone, feeding on the Southerly to South-Westerly monsoon flows.

This phase of the monsoon corresponds with one of the two peak periods of cyclone formation over waters adjacent to the Indian subcontinent. The other peak occurs at the start of the monsoon season (roughly May to June) as the trough first develops ahead of the monsoon onset.