A heavy downpour led to flash floods in several parts of Singapore on Sunday afternoon (Nov 11), including along a stretch of the Kallang-Paya Lebar Expressway (KPE).

This comes a day after flash floods hit parts of Choa Chu Kang and Bukit Batok in western Singapore, prompting investigations by national water agency PUB.

On Sunday, PUB said in statement at 3.45pm that flash floods occurred at Lorong 23 Geylang and the KPE slip road to the Pan-Island Expressway in the direction of Changi.

"All lanes are affected," the agency said, as it urged motorists to exercise caution and avoid the area.

Other locations also saw reports of high flood risk.

Water levels in the drainage systems at Yuan Ching Road/ Yung Kuang Road, Gul Circle, Sime Darby Centre, Alexandra Canal and Lorong Chuan had risen to at least 90 per cent during the downpour.

Earlier, the National Environment Agency had warned of heavy rain over the southern, western and central areas of Singapore from 1.45pm to 3pm.

It later said that rain would fall across many areas of Singapore till 4pm.

Between 4.20pm and 4.40pm, PUB tweeted that the flash floods on KPE and in Geylang subsided, adding that traffic was passable.

On Saturday evening, about 100mm of rain was recorded from 4.40pm to 6pm at Bukit Panjang, according to PUB.

This is 40 per cent of the average monthly rainfall in November.

Singapore and the region have been experiencing inter-monsoon conditions since late October.

The first two weeks of November is expected to be wetter than the previous fortnight.