The Hindu Business Line : Wet spell for 3 more days in TN likely

THERE'S going to be hardly any respite for Tamil Nadu from the ongoing wet spell at least for another three days as the causative weather system over southwest Bay of Bengal extended its vigil out into the sea.

Three days is what it should take for the system, now a well-marked `low', to move inland to the south of Chennai, says Dr Akhilesh Gupta of the National Centre for Medium Range Weather Forecasting (NCMRWF).

This makes for a slight change in the projections made earlier, which had said that the landfall would take place in the extreme peninsula and the system would push further west to slide into the Arabian Sea.

But it has been pushing north of late even as it churned slowly to the west, Dr Gupta told Business Line.

Importantly, he added, that the east-west shear zone of monsoon turbulence is seen draining itself clean by the weekend (earliest by Friday).

The shear zone acts as a magnetic field with enough drawing force to pull in, nurture and develop the slightest weather disturbance in the vicinity into potentially destructive weather systems.

The easterly flows also are seen easing out in tandem.

These prognostications indicate that the skies, which have been hanging heavy over the peninsula over the past few weeks, could be clearing up for a while, Dr Gupta said.

But for the moment, the shear zone will continue to be very active and trigger heavy to very heavy rains in Tamil Nadu and progressively into Kerala up till the weekend.

Model projections by the US Navy, the European Centre for Medium-Range Weather Forecasts (ECWMF) as well as by NCMRWF indicate the heavy rain bands concentrating over southern Tamil Nadu and adjoining Kerala.

But there are other models contending that the wet weather would extend to north Tamil Nadu as well.

In all probability, widespread to fairly widespread rainfall with heavy to very heavy spells will lash entire Tamil Nadu, especially the coastline, for the next three days.

The well-marked `low' will have made landfall by then, and will weaken progressively, helping lift the curtain of showers for sometime into the next week. According to Dr Gupta, the South China Sea also has calmed down temporarily to be of any impact to Bay of Bengal circulations.

A tropical depression has formed over the northwest Pacific and is seen heading west-northwest, letting off steam in the process.

Dr Gupta did not expect this also to travel the distance and cross the Indian territorial waters.

An update from the NCMRWF said that the well marked `low' showed slight westward movement on Monday.

The system has been causing heavy to very heavy rainfall at a few places over coastal Tamil Nadu and Pondicherry during the 24 hours ending 8.30 a.m. Moderate rainfall occurred over Rayalaseema and Kerala.

Chief amounts of rainfall (cm) are Karaikal 16; Nagapattinam 14; Chennai 13; Tambaram 11; Cuddalore and Thiruvananthapuram 5 each and Tirupati 4.

In the north, a feeble western disturbance in the form of a trough in middle tropospheric westerlies lay over north Pakistan and adjoining north Jammu and Kashmir.

It is likely to cause light to moderate rain/snow over Jammu and Kashmir during the next two-three days. Another western disturbance is likely to approach and cause scattered rain/snowfall activity over the western Himalayan region beginning Thursday.

The weak westerly trough over Northeast Bay of Bengal and neighbourhood persisted.

It is expected that this will cause the isolated to scattered rainfall activity to continue over Nagaland, Manipur, Mizoram, Tripura and Arunachal Pradesh at least for another 24 hours.

Article E-Mail :: Comment :: Syndication :: Printer Friendly Page