SINGAPORE - The latest spell of heavy and persistent rain Singapore has experienced since Monday night (May 17) had been sparked by sea breezes bringing in rainclouds over the island, a weather expert said on Tuesday.
"Sea breezes converging towards Singapore bring about squall-like storm systems that can be intense at times," said weather and climate scientist Koh Tieh Yong from the Singapore University of Social Sciences.
But the downpour on Monday night did not break any records as it was well within the usual variability in rainfall patterns experienced in the tropics, said Associate Professor Koh.
While climate change is expected to alter rainfall patterns, resulting in bouts of more intense rainfall on occasion and drier periods in others, Prof Koh said there has not yet been any evidence of this in Singapore.
"There is no scientific evidence to show that Singapore's rainfall intensity or frequency has been affected by global climate change at present," he told The Straits Times.
"Occasional heavy rainstorms are expected in equatorial regions even without climate change," he said. "Land-use changes disturb temperature and evaporation patterns and would modify rainfall over a small country like Singapore."
The Meteorological Service Singapore (MSS) said on Monday that thundery showers in the late mornings and early afternoons are expected over parts of Singapore over the next two weeks.
As Sumatra squalls - an organised line of thunderstorms - sweep eastward towards Singapore, the country will see widespread thundery showers and gusty winds between the pre-dawn hours and morning, it noted.
Drier and warmer weather is expected later this month as the monsoon rainband moves north above the equator and away from Singapore.
Overall, the rainfall for the whole of May is expected to be below average over some parts of the island, said MSS.
Over the past five months, a few record-high deluges have caused flash floods in Singapore.
On April 17, flash floods were reported across the island, with a number of pavements flooded in the western and central areas.
The prolonged heavy rain caused water levels in several drains and canals to exceed 90 per cent of their capacity. Ulu Pandan recorded 170.6mm of rainfall that day, the highest in a day for April since 1980.
There was also exceptionally high rainfall in January, making it the wettest January since 1893.