The depression in the Bay of Bengal has intensified into a cyclonic storm, and lies centred 400 km east of Chennai on Tuesday evening.
According to a bulletin issued by the India Meteorological Department, the system is likely to intensify further and cross the Andhra Pradesh coast, between Ongole and Visakhapatnam, by the early hours of Thursday.
The Department has warned that under the influence of the system, north coastal Tamil Nadu and coastal Andhra Pradesh will experience very adverse weather conditions over the next two days.
Along and off the Andhra Pradesh coast, gales with speed reaching up to 65-75 kmph are likely to begin on Tuesday night, and the speed will steadily increase to 115-125 kmph at the time of landfall.
The sea condition will be “very high” to “phenomenal,” and extremely heavy rainfall is possible in some areas during the next two days.
On the other hand, along the north coastal Tamil Nadu squally winds reaching 50-60 kmph are likely during the next 24 hours, and the sea is likely to be “very rough.” There is a possibility of extremely heavy rainfall in a few areas.
The Department has advised fishermen in the two States not to venture into the sea till the storm ends.
With the system moving rapidly towards the coast, fears of a repeat of last year's experience — the cyclonic storm ‘Aila' formed right at the beginning of the monsoon disrupting the build-up of the system — have receded. The disruption led to a severe deficiency in rainfall during June, which, in turn, resulted in the season ending with a nationwide rainfall of a mere 78 per cent of its long period average.
Experts who apprehended that the current system, ‘Laila,' might turn out to be another ‘Aila' said the rapid approach of the system towards land had dispelled such fears.
Speaking to The Hindu, they said that since the monsoon flow over the Arabian Sea was still building up, if ‘Laila' crossed the coast on Thursday, as predicted, there would still be enough time for the monsoon to evolve and lead to the onset of the monsoon over Kerala around month-end.
They also noted that weather prediction models suggested that the strength of the south westerly flow of the monsoon over the Bay of Bengal would remain intact, even after ‘Laila' crossed the coast and got weakened.
June 1 is the normal date for the onset of the monsoon over Kerala, and the Department recently issued a forecast that it could set in on May 30, subject to a model error of plus or minus four days.
The monsoon has covered more areas in the Bay of Bengal region. It has advanced over some more parts of the south-west and south-east Bay, as also some parts of the east-central Bay and the remaining parts of the Andaman and Nicobar Islands and the Andaman Seas.