18-10-2023 (SINGAPORE) The sighting of a “tornado” in Tuas on Monday morning has been clarified by experts as a waterspout, a meteorological phenomenon associated with intense thunderstorms.
Dr. David Taylor, a geography professor at the National University of Singapore, explained, “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.”
He further elaborated on the process, stating, “As with tornadoes that form and remain over land, they form as a result of spinning air currents tied-up with the instability (wind shear) associated with a thunderstorm. Initially, the air spins horizontally within the cloud, parallel with the land/water surface. The spin can become vertical, dropping below the cloud – leading to a tornado.”
The Meteorological Service Singapore (MSS) reported that intense thunderstorms were observed over the sea west of Tuas, near the Tuas Port construction site, between 9 am and 10 am on Monday. MSS noted that waterspouts typically last about 10 minutes, with larger ones lasting up to an hour. They tend to dissipate rapidly near the coast or when approaching land.
The presence of moisture from the sea contributes to the growth of thunderstorm clouds, according to MSS. While waterspouts are usually weaker than tornadoes, they can pose risks to people engaged in water sports and activities, as well as to small vessels. Waterspouts can also cause objects to be blown about.
A local media outlet reported that the weather phenomenon lifted an object weighing approximately 100kg and moved it 20m to 30m from its original location. In response to inquiries, the Maritime and Port Authority of Singapore (MPA) confirmed that there was no damage to construction equipment on the site and no injuries to personnel.
The waterspout lasted for about eight minutes, and construction workers at the site sought shelter immediately after being alerted to its presence, according to MPA.
