A low pressure area is likely form over the Southeast Arabian sea on Friday and could intensify into a cyclonic storm, the regional weather office said Thursday and warned fishermen against venturing into the sea. Rains were likely in Tamil Nadu and Puducherry in the next three days, with the possibility of heavy rainfall in one or two places, Deputy Director General of Meteorology, Chennai, S Balachandran told reporters here. "A low pressure area is very likely to form over Southeast Arabian sea by tomorrow. It is very likely to concentrate into a depression during the subsequent 36 hours and move northwestwards," he said. It is very likely to intensify into a cyclonic storm and move towards Oman, he added. Fishermen were advised not to venture into the sea from October 5-8 over the South Kerala coast, Lakshadweep area, Comorin area, Southeast Arabian sea and Central Arabian sea, Balachandran said. "Those who are in deep sea are advised to return to the coast by October 5," he added. An upper air circulation over Southwest Bay of Bengal RPT Bay of Bengal adjoining Tamil Nadu and Sri Lanka brought heavy rains to many parts of this state and neighbouring Puducherry, in the last 24 hours, he said. "Widespread rains are likely in Tamil Nadu and Puducherry in the next three days, with the possibility of heavy showers in one or two places," Balachandran added. While many areas in the state including Chennai and Puducherry received rains in the last 24 hours, some parts received heavy showers, he said. In Tamil Nadu, Kattummannarkoil in Cuddalore district and Kullambady in Tiruchirappally recorded the highest rainfall of 11 cm each in this period, he added. Heavy rain has been pounding the temple town of Rameswaram in Ramanathapuram district since Wednesday night causing hardship to pilgrims. Also, fishermen from the district could not venture into the sea owing to the rainfall and rough sea, fishermen association office-bearers said. Meanwhile, the state government has initiated measures following an India Meteorological Department forecast that Tamil Nadu may receive heavy to very heavy rainfall in most places and extremely heavy rainfall in some areas on October 7. Officials said district Collectors have been issued instructions, asking them to take required precautionary action, adding, meetings have already been called to review monsoon preparedness.