Chennai, Nov 15 (IANS) The severe cyclonic storm Gaja, which lay centred about 126 km east of Karaikal in Puducherry, is expected to cross the Tamil Nadu coast near Nagapattinam on Thursday night, Indian Meteoroligcal Department (IMD) said. According to IMD, Gaja is expected to cross the coast south of Nagapattinam in Tamil Nadu by 11 p.m. Thursday with a wind speed of 80-90 kmph gusting to 100 kmph. The IMD officials said the outer rim of the Gaja cyclone is touching Karaikal and strong winds have already started blowing in the coastal districts. Rains have started in Nagapattinam, Cuddalore, Thiruvarur districts. The IMD predicted rainfall at most places with heavy to very heavy at a few places over Tamilnadu and Puducherry. Extremely heavy rain measuring about 20 cm at isolated places is also likely over Cuddalore, Nagappattinam, Karaikal, Tiruvarur, Thanjavur, Pudukkottai, Tuticorin and Ramanathapuram districts, IMD said. Meanwhile, the Tamil Nadu government has set up relief centres in the districts of Cuddalore, Nagapattinam, Ramanathapuram, Thanjavur and Thiruvarur. People in living in low-lying areas have been shifted to relief centres. Universities and colleges have postponed their exams slated for Friday. Similarly, schools and colleges in Nagapattinam, Cuddalore and Thiruvarur will be closed on Friday. According to the AIADMK government, telecommunication companies have said they would have oil stocked for a minimum of five days in the cyclone-expected zone and for 15 days at their headquarters. The mobile telephone companies also assured the government of moving their mobile telecom towers or cell on wheels to Nagapattinam and Cuddalore. According to a statement from the state government, arrangements have been made to send bulk SMS to mobile subscribers warning about the weather issued by the emergency control centres. The Indian Navy is also on high alert and is ready to render any assistance, a statement said. Two Navy ships - Ranvir and Khanjar - are standing by to proceed to the most affected areas to undertake humanitarian aid, distress relief, evacuation, and logistic support, including proviging medical aid, the Navy said. Additionally, aircraft from Naval Air Stations Dega, Rajali and Parundu and patrolling boats from naval detachments in Ramnathapuram, Nagapattinam have been warning the fishing vessels about the approaching storm, the Navy said. Naval aircraft are also standing by to undertake reconnaissance, rescue, casualty, evacuation and air drop of relif material to the stranded.