SINGAPORE: Winds tore up the roofs of buildings near Gul Way on Friday (Sep 27) and sent the debris flying, in scenes rarely seen in Singapore.
The unusual weather phenomenon was captured in viral videos posted on social media.
The Meteorological Service Singapore (MSS) said this was the first recorded occurrence of a landspout over Singapore.
The landspout was caused by a thunderstorm that developed over the waters off Tuas at about 10.30am.
"When the thunderstorm moved inland at around 11am, the moist air feeding into the intensifying storm resulted in a rotating column of winds over Gul Way around the Tuas area," said MSS.
"This rotating column of winds, also known as landspout, is caused by the development of an intense thunderstorm under unstable atmospheric conditions, similar to a waterspout that develops over a water body."
MSS added that a landspout typically has a life span of several minutes, and weakens quickly when the thunderstorm matures or dissipates.
The closest wind sensor to the Gul Way area is located at Jurong West, about 3km away, and it recorded a low wind gust of 16.1 km/h, MSS said.
"UNLIKELY" RELATED TO CLIMATE CHANGE
Associate Professor Koh Tieh Yong, a weather scientist from the Singapore University of Social Sciences, said that whirling winds are rare but not abnormal in Singapore.
"The witnessed wind hazard is unlikely to be related to the recent dry spell or to climate change," he said.
Landspouts seldom form on land because their small size makes them vulnerable to disruptions by uneven terrain or mixed land use, he explained.
The area around Gul Way in Tuas is reclaimed and used for light industry, resulting in a wide, flat expanse with mostly low buildings.
It is also near the sea, where whirling winds can form in a thunderstorm and "migrate smoothly inland to intensify momentarily in a rising twisting motion".
"Such baby twisters are short-lived even if they are more intense than usual," said Assoc Prof Koh.
Waterspouts have been spotted in Singapore waters before.
On May 11, residents were startled by what they thought was a tornado near Tanjong Pagar Terminal.
In January 2018, a waterspout off the east coast of Singapore caused strong winds that sent boats and rubbish bins flying at East Coast Park.