The well-marked low pressure area over southwest and adjoining southeast Bay of Bengal moved west to northwestwards and intensified into a depression on Tuesday evening, the India Meteorological Department (IMD) said.

The weather system lay over southwest Bay of Bengal at 5:30 pm today, about 490 km east to southeast of Chennai and 590 km southeast of Nellore, it noted.

"It is likely to move west-northwestwards and cross north Tamil Nadu-south Andhra Pradesh coasts between Puducherry and Nellore, close to Chennai during the early morning of October 17 as a depression," the Met said in a press release.

According to a Met official, heavy to very heavy rainfall is likely at a few places in the state on Wednesday, along with extremely heavy rainfall in some isolated places.

Squally weather with wind speeds reaching up to 60 km per hour (kmph) is likely over southwest and adjoining west-central Bay of Bengal, including along and off Tamil Nadu, Puducherry and south Andhra Pradesh coasts till October 17.

The squally weather is expected to gradually subside after Thursday, the IMD said.

Earlier, heavy rains lashed several parts of Andhra Pradesh in the wake of the well-marked low pressure area over the Bay of Bengal, which moved from the southeast part of the sea towards west and northwestward direction and lay there on Tuesday morning.

The IMD had forecast vigorous monsoon activity in coastal Andhra Pradesh and Yanam on Tuesday, with fairly widespread rainfall distribution.

A similar weather pattern was also forecast for the Rayalaseema region of the southern state with widespread rainfall. Dozens of places received heavy rainfall by Tuesday morning.

Kavali in Nellore district recorded a rainfall of 15 cm, followed by Addanki (Bapatla) 14 cm, Kandukur (Nellore) 12 cm, Yanam 9 cm and Atmakur (Nellore) 8 cm, among others in coastal Andhra Pradesh region.

In the Rayalaseema region, Kodur in YSR Kadapa district registered a rainfall of 10 cm, followed by Sullurpeta and Gudur (Tirupati) 7 cm and 6 cm respectively, among others.

Meanwhile, the Andhra Pradesh State Disaster Management Authority (APSDMA) noted that parts of West Godavari, Eluru, Krishna and NTR districts were likely to receive heavy to very heavy rainfall on Tuesday.

It had also predicted a similar weather pattern for Guntur, Bapatla, Palnadu, Prakasam, Nellore, Nandyala, Annamayya, Chittoor, Tirupati and Kurnool districts.

Likewise, squally winds reaching up to 55 km per hour speed were expected along the coast.

APSDMA managing director R Kurmanadh advised people to stay alert and called on fishermen to refrain from venturing into the sea.

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