The northern limit of monsoon is expected to push towards a sliver of an area of North-West India — including the national capital, which is all what is left to be covered by it — with the expected formation of a low-pressure area over north-west Bay of Bengal off Odisha-West Bengal coasts later today (Thursday). The northern limit of the monsoon continues to pass through Nagaur, Sikar, Bharatpur, Rampur, Sonipat and Bhatinda.
Monsoon clouds spread
At 11 am, satellite pictures showed monsoon clouds spread out across parts of North-West, West India, and Central India across Gujarat, East Rajasthan, entire Madhya Pradesh, East Maharashtra, Chhattisgarh, Odisha, and North Andhra Pradesh.
Main cities falling under the footprint of cloud cover included Junagadh, Bhavnagar, Mahesana, and Vadodara in Gujarat; Udaipur, Ajmer, Jodhpur, Tonk, Bhilwara and Kota in East Rajasthan; Indore, Bhopal, Guna Shivpuri, Sagar and Jabalpur in Madhya Pradesh; Bilaspur, Raipur and entire Chhattisgarh; Sambalpur, Balasore and Bhubaneswar in Odisha.
Low-pressure area soon
A preparatory upper air cyclonic circulation persists over north-west Bay of Bengal and adjoining north Odisha-West Bengal coasts this (Thursday) morning, and has been anchoring the monsoon flows over the Bay for past few days. This circulation is expected to descend into lower levels of atmosphere to set up the ‘low’ later today.
Importantly, a helpful trough runs from north-east Arabian Sea to the above cyclonic circulation over north-west Bay across south Gujarat, north Madhya Maharashtra, Vidarbha and south Chhattisgarh. The brewing ‘low’ is expected to bend the trough towards itself so it dips into the Bay waters, and emerges with the ‘low’ in tow.
Precursor monsoon trough
The trough will provide the highway in the atmosphere for monsoon easterlies to blow from the Bay into East India, East-Central India, Central India, and West India and North-West India covering a large part of the core monsoon region. Numerical predictions indicate a sustained flow of monsoon winds from the Bay even as a circulation over north-east Arabian Sea keeps the West Coast active.
Heavy rainfall likely
Updated forecasts for North-West India said very heavy rainfall is likely over East Rajasthan for three days; over Uttarakhand for two days; over Haryana and West Rajasthan and West Uttar Pradesh tomorrow (Friday); and East Uttar Pradesh on Monday and Tuesday next.
As for West India, heavy to very heavy rainfall may lash Konkan and Goa; ghat areas of Madhya Maharashtra and east Gujarat; and isolated heavy over Saurashtra and Kutch for six days.
In Central India, very heavy rainfall is likely over Madhya Pradesh today (Thursday) and Tuesday next while over East India, very heavy rainfall is predicted for Jharkhand and Odisha today; over hills of West Bengal and Sikkim on Saturday; and Bihar, on both Saturday and Sunday.