Sri Vijaya Puram, Feb. 25: Thunderstorm with lightning is likely to occur at one or two places over A&N Islands on Feb. 26. Squally weather with surface wind speed reaching 30-40 kmph gusting to 50 kmph is very likely over Andaman Sea & A&N Islands. Sea condition is likely to be rough. Fishermen have been advised not to venture into the sea along and off Andaman Sea & A&N Islands till Feb. 27.