Amaravati, Oct 8 (IANS): The Met department has forecast isolated thunderstorms and lightning across coastal Andhra Pradesh, Rayalaseema and Yanam over the next four days on Thursday.

Heavy thunderstorms are expected in some places on Saturday and Sunday.

"A fresh low pressure area is very likely to form over north Andaman Sea and adjoining east-central Bay of Bengal by Friday. It is very likely to concentrate into a depression over central Bay of Bengal during the subsequent 24 hours," said a Met official.

The weather phenomenon is likely to move towards northern Andhra Pradesh and adjoining Odisha as a depression by Sunday afternoon or evening.

Likewise, a cyclonic circulation is currently persisting over south coastal AP and neighbourhood about 1.5 to 3.1 km above the mean sea level.

Over Telangana and neighbourhood, the cyclonic circulation is above 0.9 km mean sea level while a trough runs from the cyclonic circulation to south Tamil Nadu across Rayalaseema.