In a fascinating contest for earning the right to steer the monsoon over the landmass, the Bay of Bengal appears to be conjuring up the next low-pressure area after Cyclone Nisarga from the Arabian Sea crossed the North Maharashtra coast on Wednesday and is weakening.

The Nisarga remnant would enter Central and East India with its rain bands before drifting into the foothills of Bihar and South-East Uttar Pradesh and fading out over Nepal, India Meteorological Department (IMD) projections said. Coupling with an incoming western disturbance, it may pour down heavily over these regions.

IMD, US models

The new low may take shape over the East Bay, which — like the rest of the basin — has warmed up suitably a fortnight after the torrents associated with Cyclone Amphan had cooled it. The low may become a depression and orient itself perfectly towards the monsoon sweet spot of Head Bay around June 10. A short to medium term model guidance from the IMD suggests that the depression and heavy rain bands could sweep their way into East India and the farming heartland.

Rain for heartland

The US Climate Prediction Centre points to a second disturbance entering the Bay, and there is a moderate potential for the formation of a depression as it moves northwestward towards East India or Bangladesh. Another cyclone here is ruled out because it is rare after the onset of the monsoon.

This Bay depression may move into West Uttar Pradesh per forecasts valid until June 13, driving the monsoon from the Bay into East and Central India, setting up the most ideal scenario ensuring adequate rain coverage over the region. Arrival of a western disturbance will further busy up the proceedings further.

Lull over South-West

The Arabian Sea and Bay arms of the monsoon will have thus been established, though a lull is likely over the South-West coast (Arabian Sea) after Cyclone Nisarga. The monsoon flows are forecast to be good, but they would go to feed a rogue circulation forming off the Yemen-Oman coasts.

The depression in the Bay would still be able to pull in the monsoon westerlies into the northern part of the West Coast and adjoining Central India, bringing another wet spell into those areas. The Kerala and Karnataka coasts are likely to remain relatively drier during this period, models suggest.

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