A low-pressure area is likely to form over the Bay of Bengal, on 11th July ending the weak monsoon phase over central and northern parts of the country. Monsoon had gone in to limbo following shift of trough close to the foothills for the last 10 days or even more. Rainfall activity was mostly confined to east and northeast India. Excessive rains along the foothills of Bihar and catchment areas of mountainous ranges of Nepal led to flooding of rivers submerging northern districts of Bihar like, Champaran, Sitamarhi, Madhubani, Supaul, Madhepura, Muzaffarpur, Darbhanga, Araria, Kishanganj and Purnea.
Only one low-pressure area has formed so far in this season. This weather system formed over the North Bay of Bengal on 11th June and expedited advance of monsoon over east, northeast and central parts of the country. Monsoon current got blocked after reaching outskirts of Delhi, West Uttar Pradesh, Punjab and Haryana. The line of monsoon remained stagnant for over 3 weeks and continue to pass through Ambala and Amritsar. Fresh developments on account of formation of low-pressure will lead to favorable conditions for travel of monsoon to cover most remaining parts in the next 3 days. The last pickets of West Rajasthan may wait a little longer.
Low-pressure area will form over the Bay of Bengal slightly south of normal position, off North Andhra Pradesh and South Odisha Coast on 11th July, coinciding date of 1st low-pressure in June. This feature will be preceded by a closed and compact cyclonic circulation over the same area on 10th July and quickly organize to manifest on sea surface as low-pressure the very next day. The system will have a tendency to shift to the north before crossing the coast on 12th July. In all probabilities, the 2nd low-pressure of the season will cut across Odisha, Chhattisgarh, Madhya Pradesh and Rajasthan. The peripherals on either side of the track will have their share of decent rains.
Prior to this low-pressure area, a cyclonic circulation is forming over the head of Bay of Bengal. This system will move inland quickly, spread over a large area covering West Bengal, Jharkhand, Odisha, Chhattisgarh, and Madhya Pradesh. This pattern will increase the span and force of monsoon easterly winds across the Indo Gangetic plains over the next 3 days. While reaching over North Madhya Pradesh, its interaction with another cyclonic circulation over Punjab, North Rajasthan and Pakistan region will trigger monsoon rain and thundershowers in the subsequent 72 hours between 11th and 14th July over North India. This will lead to onset of monsoon over Delhi and other left over parts of Punjab, Haryana and East Rajasthan.
