Sri Vijaya Puram, Oct. 26: Thunderstorm with gusty wind (40-50 kmph) and lightning is very likely to occur at one or two places over A&N Islands on Oct. 27. Thunderstorm with gusty wind (30-40 kmph) and lightning is also very likely to occur at one or two places over A&N Islands on Oct. 28. Heavy rain (07-11 cm) is very likely to occur at one or two places over A&N Islands and thunderstorm with gusty wind (30-40 kmph) and lightning is also very likely to occur at one or two places over A&N Islands on Oct. 29. Fishermen have been advised not to venture into the sea along and off A&N coasts till Oct. 27.