The India Met Department has confirmed on Friday that the South-West monsoon has started withdrawing from the western parts of Rajasthan in what is a month-long process.
This came on a day when the all-India rain deficit shot up for the first time beyond the 12 per cent forecast by the Met for the entire season this year.
Deficit worsensThe gradual drying of the North-West and adjoining Central India is expected to worsen the overall deficit figure over the next three to four days, according to indications.
An anti-cyclonic circulation that heralds the dry weather was present at the lower levels of the atmosphere over north-west India on Friday.
The anti-cyclone has clock-wise winds around it, has high-pressure, and sits heavy over the ground, suppressing the formation of clouds and precipitation.
This is the exact anti-thesis of the monsoon feature of lower pressure, ascending motion of air into higher levels of atmosphere where it cools, and condenses the vapour mopped up by winds from the ocean. This is what precipitates as rain.
Bay humming?Wind profile projections that a western disturbance (low-pressure system) coming in from across the border will dig south into North Arabian Sea and emerge with moisture to be rained down over Gujarat/Rajasthan.
This may unsettle the anti-cyclone during the next week but it will come back into shape by the weekend, according to these projections.
Meanwhile, global models also suggest the possibility of the East Bay of Bengal springing a surprise by hosting a likely low-pressure area by middle of the month.
A couple of cyclonic circulations trackers featured by the US Climate Prediction Centre suggested that the ‘low’ may pick up in strength and hit the East Coast.
But they seemed to differ as to which part of the coast might take the hit.
One model suggested the southern tip of peninsula and adjoining Sri Lanka while another pointed to the Andhra Pradesh-Odisha coast.