Flash floods reported in western Singapore; 36% of December’s average rainfall recorded in under 2 hours

SINGAPORE: Several flash floods broke out in western Singapore on Thursday (Dec 4) after heavy rainfall across the island in the afternoon, national water agency PUB said.

The heaviest rainfall of 113.4mm was recorded in the west from 1.45pm to 3.25pm, PUB said in a post on Facebook.

This amount corresponds to 36 per cent of Singapore's average monthly rainfall in December and falls within the top 2 per cent of maximum daily rainfall records since 1978.

The intense rain temporarily overwhelmed the capacity of surrounding drains and canals, causing flash floods at the junction of Boon Lay Way and Corporation Road, Boon Lay Avenue (between Jalan Boon Lay and Boon Lay Drive), Pandan Road and Pesawat Drive.

Quick response teams were deployed to direct traffic away from flooded lanes and provide assistance to motorists.

"Flooding subsided within 30 minutes at all four locations," said PUB.

In its weather forecast for the first half of December, the National Environment Agency (NEA) said on Monday that northeast monsoon conditions are expected to prevail, with winds blowing mainly from the northwest or northeast.

Moderate to heavy thundery showers are expected over parts of Singapore on most afternoons.

"The showers may extend into the evening on a few of these days. The total rainfall for the first fortnight of December 2025 is forecast to be near average over most parts of the island," NEA added