Director in-charge of Bhubaneswar centre of Indian Meteorological Department SC Sahu said, rains or thundershower are likely to occur at many places in Koraput, Gajapati and Malkangiri districts and one or two places in the interior districts during the next 12 hours.
The well-marked low-pressure area over southeast Bay of Bengal & neighbourhood lay centred at about 1160 km to the southeast of Machilipatnam and 1250 km south-southeast of Gopalpur on Wednesday.
The system is likely to move north-northwestwards and reach north Andhra Pradesh and south Odisha coasts around December 9 morning, it said, adding the system is likely to intensify further into a deep depression in the next 24 hours.
As many as 18 districts including Khurda, Cuttack, Puri, Kendrapara, Jagatsinghpur, Bhadrak, Balasore, Ganjam, Gajpati, Rayagada and Malkangiri are to be affected due to the deep depression and would experience more rainfall. Squally winds with a speed of 40 to 50 kmph and gusting up to 60 kmph is likely to prevail along and off Odisha coasts till December 10. Distant cautionary signal number one (DC-I) has been hoisted at Paradip and Gopalpur ports.
Sea condition will be rough to very rough around Andaman and Nicobar Islands during next 24 hours and the same will remain along and off Andhra Pradesh and south Odisha coasts from today in the evening till Saturday morning. The met department in its forecast on Thursday also predicted heavy rain in the coastal areas of Gangetic West Bengal on Friday owing to formation of a depression in the Bay of Bengal.
"Moderate rain bordering on the higher side is likely to occur in Kolkata tomorrow", Mr. Das said.