Low-pressure area over Bay of Bengal to trigger heavy rain over T.N. till Thursday

Tamil Nadu Chief Minister M.K. Stalin has instructed the authorities to declare October 15 a holiday for schools and colleges in Chennai, Tiruvallur, Kancheepuram, and Chengalpattu districts

A low-pressure area that formed over the southeast Bay of Bengal during the early hours of Monday will set the stage for widespread rainfall, particularly over north Tamil Nadu, and herald the onset of the northeast monsoon over the State. The Regional Meteorological Centre (RMC), Chennai, has predicted that the northeast monsoon is likely to arrive over the southern peninsular region by October 16 or 17.

While the heavy rainspell will last till October 17, the RMC has forecast that heavy rain, set to begin over north Tamil Nadu and the delta districts will intensify on October 15 and 16. The Meteorological Department issued a red alert on Wednesday, indicating that places in Chennai and its surrounding districts and five other northern and delta districts will have to brace for extremely heavy rainfall, above 20 cm.

In view of this, Tamil Nadu Chief Minister M.K. Stalin has instructed the authorities to declare October 15 a holiday for schools and colleges in Chennai, Tiruvallur, Kancheepuram, and Chengalpattu districts.

Rainfall will pick up pace gradually from Monday night and spread across Tamil Nadu during the week. The low-pressure area will further consolidate as a well-marked low-pressure area on Tuesday and move towards north Tamil Nadu, Puducherry, and south Andhra Pradesh coast by October 16 and October 17 and trigger a downpour, officials said.

In its bulletin, the RMC said most places would receive light to moderate rainfall in the State from October 15. While some of the delta districts have been issued an orange alert, indicating rainfall of very heavy intensity (above 12 cm), it will be the turn of north Tamil Nadu districts to experience intense rainfall on Wednesday.

S. Balachandran, Additional Director General of Meteorology, Chennai, said a depression over the central Arabian Sea was likely to move towards the Oman coast by Tuesday. The interaction between the two weather systems would push moisture-laden clouds into the region and cause intense rainfall.

Noting that the heavy rain spell was seasonal, he said the impact of monsoon rainfall depended on various local conditions and on existing infrastructure of a particular area. Red alert does not mean extremely heavy rainfall in the entire region, and the amount of rainfall may differ between areas.

Budalur in Thanjavur district received the heaviest rainfall of 12 cm in the State during the past 24 hours, ending at 8.30 a.m. on Monday. Light to moderate rainfall continued at places including Coimbatore (6 cm), Karaikal, Cuddalore, and Thoothukudi (2 cm each), and Mahabalipuram (1 cm).

The withdrawal of the southwest monsoon in one or two days will pave the way for the simultaneous setting in of the easterly and north-easterly winds and the northeast monsoon over Tamil Nadu, a bulletin said. Even as Tamil Nadu braces for the northeast monsoon, the State has already recorded 68% excess rainfall since October 1.

Fishermen have been advised not to venture into the sea till Friday as squally winds, gusting up to 55 kmph, are expected.

Published - October 14, 2024 07:52 pm IST