The Monsoon performance is directly linked to the Monsoon systems that occur in both the Bay of Bengal and the Arabian Sea. These systems like offshore troughs, vortices, cyclonic circulations, low-pressure areas and depressions decide the overall performance of Monsoon in India.
Usually, cyclones occur in the first half of June. Cyclone Ashobaa, which was a low-pressure area in the Arabian Sea and further strengthened into a cyclone is one such example. Cyclones are not common during the rest of the Monsoon period including July, August and even September.
Monsoon systems form in both Bay of Bengal and the Arabian Sea. The Bay of Bengal is the major driver of Monsoon and is largely responsible for giving rains to the country during this period. The Arabian Sea on the other hand, controls mostly the northern and western parts of India. The track of these systems influences Monsoon currents and rains.
Systems in the Bay of Bengal enhance rain activity in the country irrespective of their track, However, if the systems in the Arabian Sea move away from the coast, they take away the rain, further weakening the Monsoon surge as it happened with Cyclone Ashobaa. On the other hand, if the systems come towards the coast, rainfall activity increases over the region.
As mentioned before and as per the model indicators, a cyclonic circulation is being formed in the North Bay of Bengal around June 17 and is likely to get stronger by June 19. In its organizational stage, it is likely to move closer to Odisha and West Bengal and give good amounts of rain in the region. Here, it could turn into a low-pressure area.
As it usually happens, during the organisational stage of the system, Northeast India will observe minimal weather activity. This means that in the next 2 to 3 days, the region will not witness much activity in terms of weather, particularly Assam and Arunachal Pradesh. But, after the system moves inland, Northeast India will observe good amount of rain.
This is the first Monsoon system that is being formed in the Bay of Bengal. When it crosses coast, it will trigger Monsoon activity across most parts of Northeast India, Odisha, West Bengal, Andhra Pradesh, Telangana, along with parts of Central India including Madhya Pradesh and Maharashtra. The third week of June is expected to get good amounts of rain in most parts of the country.
The rain belt will further shift and cover more parts of the country giving rain in the region.
Image Credit: jagran.com