Twin low-pressure areas to launch N-E monsoon into scintillating phase bl-premium-article-image

Vinson Kurian Updated - November 30, 2019 at 05:08 PM.

Heavy to very heavy rain forecast for Tamil Nadu and Puducherry for three more days

The North-East monsoon is preparing to leave behind a dreary and lean November and may have just launched itself into a scintillating phase into early December, powered by two low-pressure areas.

The first one has already formed and India Meteorological Department (IMD) has located it over the Equatorial Indian Ocean and adjoining South-West Arabian Sea, some distance away from the Kanyakumari coast. It is likely to move west-north-westward and become more marked (intensified) during the next two days.

Twin low-pressure areas

The second one may form over South-East Arabian Sea and the adjoining Lakshadweep area by tomorrow (Sunday) and this too may become more marked during subsequent 24 hours.

Both these systems would take advantage of the ongoing easterly wave activity across the Bay of Bengal to flourish and intensify. These periodical waves from the Bay of Bengal are known to trigger formation of weather systems such as low-pressure areas, and even depressions/cyclones.

An early outlook (subject to verification) of the US National Centres for Environmental Prediction-Global Ensemble Forecast System (NCEP-GEFS), the second one might negotiate the Lakshadweep Islands and go on to become a depression, if not a cyclone, oriented towards the northern parts of India's West Coast.

The first one may also intensify, but to a limited extent only, since it would not be pinned down into the sea for an extended period and doesn't have much area to travel either.

The combined pull effect of the two systems would dramatically ramp up the North-East monsoon, setting up heavy to very heavy rainfall activity over the South Peninsula, including Tamil Nadu, Puducherry and Karaikal.

Heavy rains recorded already

An IMD outlook suggested that a fairly widespread to widespread rainfall regime punctuated by isolated heavy to very heavy falls may prevail over Tamil Nadu, Puducherry, Karaikal, Kerala, Lakshadweep during the next three days.

The 24 hours ending on Saturday have already witnessed rain or thundershowers at many places over Kerala, Tamil Nadu, Puducherry and Karaikal; at a few places over Lakshadweep and at isolated places over Interior Karnataka and the Andaman & Nicobar Islands.

Some of the heaviest rain were reported from Tamil Nadu with a number of centres recording rainfall amounts above 10 cm or above. These included Talaignayar (16 cm); Mayiladuthurai (14 cm); Pudukottai (13 cm); Anaikaranchatram and Kattumannarkoil (12 cm each); Papanasam, Ramanathapuram, and Tarangambadi (11 each); Rameswaram, Vallam and Needamangalam (10 cm each).

Other centres recording heavy rain (in cm) in Tamil Nadu and elsewhere were : Kanyakumari -9; Karaikal and Nagapattinam-6 each; Pamban-5; Tiruchirappalli, Palayankottai-4 each; Numgambakkam, Cuddalore, Madurai, Punalur, Thiruvananthapuram and Thoothukudi-2 each.

Outlook for the rest of the day today (Saturday) said that thunderstorms accompanied with lightning may lash isolated places over South Interior Karnataka, Rayalaseema, Kerala, Coastal Andhra Pradesh, Tamil Nadu, Puducherry, Karaikal and Lakshadweep.

Rain, squally weather forecast

Heavy rainfall is likely at a few places with very heavy falls at isolated places over Tamil Nadu, Puducherry and Karaikal while it would be heavy at isolated places over Coastal Andhra Pradesh, Rayalaseema, Kerala and Lakshadweep.

Squally weather with winds speeding up to 40-50 km/hr (depression strength) over South-West Arabian Sea and adjoining Equatorial Indian Ocean and over the Comorin area, Maldives and adjoining Lakshadweep area. Fishermen are advised not to venture into these areas.

Outlook for tomorrow (Sunday) said that thunderstorms accompanied with lightning are likely at isolated places over Rayalaseema, Coastal and South Interior Karnataka, Kerala, Coastal Andhra Pradesh, Tamil Nadu, Puducherry, Karaikal and Lakshadweep.

Heavy rainfall is forecast at a few places with very heavy falls at isolated places over Tamil Nadu, Puducherry and Karaikal; heavy to very heavy at isolated places over South Interior Karnataka, Kerala, and Lakshadweep; and heavy at isolated places over Coastal Andhra Pradesh and Rayalaseema.

Squally weather with winds clocking up to 40-50 km/hr in speed (depression strength) may prevail over the South-West Arabian Sea and adjoining Equatorial Indian Ocean and over Lakshadweep and the adjoining Maldives area and the South-East Arabian Sea along and off the Kerala coast. Fishermen are advised not to venture into these areas.

Published on November 30, 2019 11:34