The Meteorological Service Singapore said intense thunderstorms were observed over the sea west of Tuas.
The Meteorological Service Singapore said intense thunderstorms were observed over the sea west of Tuas.
A "tornado" that was spotted in Tuas on Monday morning was a waterspout, say experts.

Dr David Taylor, a professor of geography at the National University of Singapore, said: "It's a waterspout - a tornado that forms either over water or originates on land and then moves over water.

"Tornadic waterspouts occur around Singapore occasionally, associated with powerful thunderstorms. They are generally no stronger than the weakest tornadoes that form over land and remain land-based.