The depression over Bay of Bengal crossed the coast between Tamil Nadu and Andhra Pradesh early on Friday, the India Meteorological Department (IMD) said and announced that the weather system will gradually weaken.
It forecast more rains for the state and heavy to very heavy rainfall in parts of AP and Karnataka.
Meanwhile, there was a let-up in rainfall in northern districts of Tamil Nadu and neighbouring Puducherry, especially on Friday morning, even as the IMD said the depression will gradually weaken into a well marked low pressure in the next 12 hours.
Following heavy rains in Andhra Pradesh and resultant high flow of water between Tada and Sullurpetta, the Southern Railway announced cancellation--both full and partial - of various trains, besides diverting some others .
"The Depression over southwest Bay of Bengal off north Tamil Nadu coast moved west-northwestwards and crossed north Tamil Nadu & adjoining south Andhra Pradesh coasts between Puducherry & Chennai .... during 0300-0400 hrs IST (3-4 am) of today, the 19th November, 2021," an IMD bulletin said.
It lay centred at 5:30 am as of Friday over north coastal Tamil Nadu and neighbourhood and about 60 km south-southwest of Chennai and 60 km north-northeast of Puducherry.
"It is very likely to continue to move west-northwestwards and weaken gradually into a Well Marked Low Pressure Area during next 12 hours," it said.
Under its influence, thunderstorm with light to moderate rain is likely to occur at many places over Tamil Nadu and Puducherry during the next 24 hours. Heavy rain is likely at isolated places over Krishnagiri, Dharmapuri, Vellore, Tirupattur, Erode and Salem districts of Tamil Nadu during the same period, the regional weather office said.
It added squally wind speed reaching 45-55 kmph gusting to 65 kmph was likely to prevail over southwest and adjoining west-central Bay of Bengal and along and off Tamil Nadu, Puducherry and adjoining south Andhra Pradesh coasts during next six hours and decrease gradually thereafter.
The IMD forecast light to moderate rainfall at most places with heavy to very heavy rainfall at isolated places as very likely over south coastal Andhra Pradesh, Rayalaseema and south interior Karnataka and heavy rainfall at isolated places over Telangana, coastal and north interior Karnataka for Friday.
Meanwhile, the Southern Railway announced cancelling many services, following "heavy rain and consequent water level flowing at danger level at Bridge No.167 between Tada and Sulurupetta Stations (in AP)."
Services to and from Tirupati, which was caught in a massive flood on Thursday, from here are among the cancelled ones while the Railways also announced diversion of trains including the Hazrat Niazmuddin-bound Rajdhani Express.
Meanwhile, schools remained closed in many districts in Tamil Nadu, including Chennai and its nearby ones, and those in the neighbouring Puducherry union territory on Friday.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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