Vinson Kurian

Promises to be the most productive

Thiruvananthapuram , June 26

The National Centre for Medium Range weather Forecasting (NCMRWF) has upgraded as fair the chances of a long-awaited `low' taking shape over the Bay of Bengal.

The `low' is now expected to take shape around June 29, to coincide with the genesis of a counterpart cyclonic circulation over the North Arabian Sea in what promises to be the most productive session yet of the current edition of monsoon, said Mr J.V. Singh of the NCMRWF.

`Low' forecast

The forecast for the `low' may have come to be deferred, but most models are reasonably confident that the cyclonic circulation over the west-central and adjoining Northwest Bay would descend down to lower levels to set up the system.

The Arabian Sea system would catch up sooner rather than later.

Together, they would be able to drive up fairly widespread to widespread falls over areas in the north and east not covered by the onset monsoon pulse. According to Mr Singh, it's normal for one end of the offshore trough along the southwest coast to close contours and converge into a cyclonic circulation. But on Monday, a separate upper air cyclonic circulation had already been detected over the Northeast Arabian Sea. Either of these could go to set up a `low' here as well.

Welcome rains

In any case, a mass of rain-bearing clouds straddled the landscape on Monday, extending right from the west over the North Arabian Sea to the east over the south Bay of Bengal. The prospective sea-based systems are expected to park themselves to extreme ends of this formation to either side of the peninsula.

The easterlies are also seen penetrating the peninsula, with the tropical jet having notched up speeds of around 45 knots on Monday. An ideal monsoon setting presupposes the jet cruising at a crisp 60 knots. But this would most likely be achieved with the circulation over the Bay concentrating into a `low.'

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