New low-pressure area forms over Bay of Bengal; heavy rain likely in Tamil Nadu

CHENNAI: The new low-pressure area formed over the Bay of Bengal on Monday and is likely to intensify and move towards the Tamil Nadu coast in the next two days, the Regional Meteorological Centre (RMC) said. The department has predicted heavy to very heavy rainfall over coastal districts of TN, including Chennai, Tiruvallur, Kancheepuram and Chengalpattu districts, till December 19.

Under the influence of the upper air cyclonic circulation over southeast Bay of Bengal, a low-pressure area has formed over central parts of south Bay of Bengal today. The associated cyclonic circulation extends up to 3.1 km above mean sea level. It is likely to become more marked and move west-northwestwards towards the Tamil Nadu coast during the next two days.

The system prevailing over the sea is likely to bring heavy to very heavy rain over the Chengalpattu, Cuddalore, Villupuram, and Mayiladuthurai districts. Similarly, Chennai, Kancheepuram, Tiruvallur, Thiruvarur, and Nagapattinam districts of Tamil Nadu are likely to witness heavy rainfall on Tuesday.

Since the low-pressure area is likely to further intensify into a well-marked low-pressure area in the next 48 hours, an orange alert has been issued for Chennai, Chengalpattu, Tiruvallur, Kancheepuram, Cuddalore and Villupuram districts of Tamil Nadu. At least six districts might witness heavy rainfall - Ranipet, Tiruvannamalai, Kallakurichi, Vellore, Ariyalur, and Mayiladuthurai on December 18 (Wednesday).

The weather department has given a yellow warning for Chennai, Chengalpattu, Tiruvallur and Kancheepuram districts, predicting heavy rainfall on December 19. The rest of the state, especially north TN and a few places in southern parts of the state, is likely to receive light to moderate spells in the next few days. The rainfall activity is expected to gradually reduce from Friday (Dec 20), since the system is likely to weaken. However, light to moderate spells have been predicted across the state in the coming days.

Meanwhile, the fishermen are advised not to venture into the sea till Thursday. As the strong wind speed reaching 35 kmph to 45 kmph gusting to 55 kmph is likely to prevail along and off the Tamil Nadu coast, adjoining the Comorin area, Gulf of Mannar, and south Andhra Pradesh coast. The officials have urged the fishermen who went for deep-sea fishing to return to the shore at the earliest since the weather pattern is likely to concentrate and there might be changes in wind flow pattern.