Port Blair, Oct. 13: Thunderstorm with lightning likely to occur at one or two places over Nicobar Islands on Oct. 15, 16 &17. For further enquiries/information, one may contact helpline of State Emergency Operation Centre at Helpline No. 1070 & District Emergency Operation Centre at Helpline No. 1077. For any emergency/assistance at sea, call Coast Guard SAP Agency at Toll Free number 1554, a press release from Directorate of Disaster Management said.