Cyclone Laila may stall monsoon advance for 1-2 days

A depression over southwest Bay of Bengal, which had intensified into the cyclonic storm “Laila”, could stall the progress of the southwest monsoon for a couple of days but would have no bearing on the onset of rains over Kerala on May 30, a senior Met official said today.

“As of now, the cyclone, which is embedded in the monsoon system, is helping advance of monsoon over Andaman Sea. As it moves north, it will detach from the monsoon. Energy of the monsoon current will get distributed and it may weaken for a few days,” DS Pai, director of long range forecast at the India Meteorological Department said.

He said the monsoon system would remain weak till the cyclone hit a landfall or weakened. “This could take two-three days.”

Pai said the temporary weakening of the current, however, was unlikely to have any impact on the onset of monsoon over Kerala coast.

“The date of onset is still 12 days away. The monsoon current would have built up again by then,” he said.

The Met department has said the cyclone was expected to intensify and move in a north-westerly direction towards the Andhra coast.

At 0530 IST, the storm centered over southeast Bay of Bengal, about 70 km east-southeast of Chennai, 800 km southeast of Visakhapatnam and 1,300 km south-southwest of Kolkata.

Another Met official said so far there were no indications that Laila may develop along the lines of last year’s ‘Aila’, which had robbed the southwest monsoon current of moisture and momentum.

Aila had been one of the major factors responsible for last year’s drought, along with El Nino.

In 2009, June-September monsoon rains were 22 per cent below normal, and more than half of the country’s 623 districts faced a severe drought.

“We cannot be very certain, but so far the track of the cyclonic storm appears to different, its timing is also different...I don’t think it will have the same impact on monsoon as Aila,” the official said.

Aila had hit Bay of Bengal on May 25, bringing very heavy rains and floods in the coastal areas of West Bengal. It had developed within the monsoon system, but intensified as it moved away, preventing the flow of the monsoon current over the Indian subcontinent.

The official said this year, since the monsoon was yet to reach Indian shores, the impact of the cyclone on the monsoon current would be temporary and much weaker compared to the last year.

The monsoon has already set in over parts of south Bay of Bengal, Andaman and Nicobar Islands and most parts of Andaman Sea.

The Met department said under the influence of Laila, coastal areas of northern Tamil Nadu and Andhra Pradesh were likely to experience fairly widespread rainfall with isolated heavy to very heavy rains from Wednesday.

It said gale force winds with speed reaching 65-75 km per hour were likely to commence along and off Andhra coast from tonight, and advised fishermen not to venture out into the open sea.