The India Meteorology Department has extended to Friday the outlook for heavy (7-11 cm) to very heavy (12-20 cm) rainfall at one or two places in Kerala as the countdown for the monsoon onset continues.
Conditions continue to be favourable for the onset of the South-West monsoon over the Kerala coast during the next 48 hours, it said in a bulletin.
The 24 hours ending Monday morning witnessed rain at most places in the State and at many places in Lakshadweep.
Stations reporting heavy rain included Vaikom (8 cm) and Piravom (7 cm). Other chief amounts of rainfall (in cm) are: Mancompu-6; Taliparamba and Kurudamannil-5 each; and Kayamkulam and Aluva - 4 each.
The Met has retained the outlook for strong westerly winds with speeds occasionally reaching up to 55 km/hr along and off the Kerala coast and over the Lakshadweep archipelago for the next 24 hours.
There is an emerging model consensus on the probability of heavy-to-very heavy rain along the West Coast for the first two weeks after the onset of the monsoon.
A cyclonic circulation over East-central Arabian Sea off Karnataka should keep the pot boiling here as it breathes in moisture-laden winds from the Arabian Sea and pumps rain along the coast.
Heading north Projections by most models suggest that the circulation will carry with it the ‘leading edge’ of the monsoon further into the north into Goa, Konkan-Mumbai, and adjoining Gujarat.
On the other side, a persisting cyclonic circulation over the West-central Bay of Bengal off the Andhra Pradesh and South Odisha coast will keep the monsoon in good stead over the East Coast.
The presence of a cyclonic circulation on each side of the peninsula will ensure that most parts of the interior peninsula too will stay wet, with heavy rain forecast over Central Maharashtra and its neighbourhood.
Storm watch The European Centre for Medium-Range Weather Forecasts is of the opinion that the cyclonic circulation off the Andhra Pradesh coast may intensify as it moves north-east towards the Gangetic West Bengal coast.
The agency has put a watch for intensification of the system into a minor storm by Saturday before it washes ashore over the Bangladesh coast the next day.
A storm tracker of the US Climate Prediction Centre agrees with this scenario but indicates a ‘splash-over’ at the Gangetic West Bengal coast instead of Bangladesh.
Meanwhile, ideal conditions for the onset and advance of the monsoon are evolving elsewhere with seasonal heat-wave conditions getting anchored over North-West India. A severe heat wave has been reported from isolated places over Rajasthan, while it was only slightly cooler over Gujarat and West and East Madhya Pradesh during the 24 hours ending on Monday morning.
The extent to which the North-West heats up will determine how low atmospheric pressure can get so that the monsoon winds can blow in from a high-pressure area in the Arabian Sea/Bay of Bengal.