Monsoon low-pressure areas have not formed over the Indian seas for the last about 2 weeks. Before this lull, the Bay of Bengal (BoB) and the Arabian Sea, both remained active. Low-pressure area developed over BoB off Odisha coast on 09thJul. The cyclonic circulation persisted and it became well marked on 12th July. The forward section of this system extended the shear zone over the central parts covering Chhattisgarh, Maharashtra and Madhya Pradesh. The spiral activity even reached parts of Gujarat and Rajasthan. The weather system became less marked on 14thJuly.
The remnant of BoB system reached North Gujarat as cyclonic circulation. This feature entered the Arabian Sea on 15th July. It became well marked low pressure area first and then intensified in to a depression over Northeast Arabian Sea on 16thJuly. This weather system moved westward along Pakistan coastline and reached Northwest Arabian Sea on 18thJuly. It continued shifting west and became less marked on 19thJuly.
Following the passage of these 2 systems, the monsoon trough shifted northward. It remained north of its normal position and carried the rainfall belt also to Northwest India and Indo Gangetic plains. Monsoon trough has been oscillating since then, under the influence of western disturbances, swinging it north and south. Western end of the monsoon trough still remains north of normal position.
A cyclonic circulation is marked over West Central and adjoining Southwest BoB. This is likely to shift along the coastline of Andhra Pradesh and Odisha. Also, it is expected to consolidate and get organized in the next 24hr. Later, it may turn in to a low pressure area over Northwest BoB and Odisha-West Bengal coastline. This will stop the hiatus of monsoon and resume active conditions, replicating 2nd and 3rdweek of July.
Low pressure area and its cyclonic circulation will cross over to land on 07thAug. Eastern end of the monsoon trough will be dragged far to the south. The weather system will track along the central parts covering Odisha, Chhattisgarh, Maharashtra, Madhya Pradesh, Gujarat and Rajasthan over the next 3-4 days. The heavy rainfall belt will gradually travel from the far east to the far west, between 07th and 11th August. There are early indications of yet another circulation developing on 12th Aug over Northwest BoB. It is little early to preempt the course of action. However, this may take over the baton and continue the monsoon burst well in to 02nd & 3rd week of August.
