The South-West monsoon has completed coverage of the entire country ahead of the scheduled timeline of July 15, the India Met Department announced on Wednesday.

The 24-hour period up to Wednesday morning saw heavy to very heavy rainfall at isolated places over Madhya Maharashtra while it was heavy over Gujarat, Madhya Pradesh and Gangetic West Bengal.

Systems weaken

Wednesday also saw the two main supporting systems — a low-pressure area over North-West Madhya Pradesh and the offshore trough along the West Coast — weaken one after the other.

This is considered a precursor to the weak phase that the monsoon is likely entering over the next couple of days. The Met has already indicated that the ‘axis’ of the monsoon would migrate to the foothills of the Himalayas during this phase.

During the active phase of the monsoon, the axis is centred along a North-West to South-East alignment linking Rajasthan with the Bay of Bengal and laid out across the plains of North India.

Monsoon systems (low-pressure areas and others) originating in the Bay move in over land through a corridor (trough) built around the axis, spreading rain over Central and North-West India.

Movement of the axis towards the foothills of the Himalayas will take the belt of heavy rain to that region, covering Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Uttar Pradesh, Bihar and North-East India.

Global weather models, too, have been alluding to the emerging weak phase. The US Climate Prediction says that July 13 to 19 would witness a ‘break’ in the monsoon over South Asia.

In the week that follows (July 20 to 26), the ‘break’ phase should shift northward over South Asia and expand over South-East Asia, with some ‘moisture recharge’ over southern India.

In other words, the US agency is indicating that the dry phase in the monsoon will alternate between southern and northern parts of the country during the next two weeks.

The second week will witness a limited revival of the monsoon over South India, thanks to the movement of a helpful Madden-Julian Oscillation (MJO) wave across the Indian Ocean, even as North India dries up.

comment COMMENT NOW