When it rains, it pours — during the peak hours of a Monday morning, no less.

National water agency PUB issued island-wide flood risk alerts amid the heavy rain on Monday (Oct 14) morning.

The National Environment Agency (NEA) said that heavy rain was expected over northern, western and central areas of Singapore from 8.05am to 8.45am in an announcement at 7.55am.

At around 8.30am, the agency added that rain is also expected over southern, eastern and central areas from 8.40am to 10.15am.

Between 8am and 9.15am, PUB issued 19 flash flood warnings in places such as Sunset Way, Bedok, Joo Chiat Avenue and Ulu Pandan Road, The Straits Times reported.

Many netizens shared photos of the flash floods on social media.

"Pouring down non-stop since 7.30am," Facebook user Vivek Gns said in a Facebook post at around 10am, sharing photos of a full canal near Botanic Gardens.

"It's so irritating when it rains during the office commute… had to queue up to take the NUS shuttle bus, as we definitely cannot walk in the garden to the office," he added.

Another post by Facebook user Jojo Jojo shows the flash flood on the roads outside Lakeside Towers, forcing vehicles to drive slowly as they plough through the water.

According to NEA, the rain is expected to lighten by Monday afternoon.

The agency's four-day outlook shows that thundery showers are expected on Tuesday to Friday, ranging from morning to early afternoon on each day.

Meanwhile, the fortnightly weather outlook from Oct 1 to Oct 15 indicates that inter-monsoon conditions — light, variable winds and higher lightning activity — are expected during the first week of October amid the weakening southwest monsoon.

"Thundery showers are expected over parts of the island in the afternoon on most days in the first fortnight of October," NEA stated. 

"The showers may extend into the night on a few days. The total rainfall for the first fortnight of October is forecast to be above average over most parts of the island."

ALSO READ: Fallen trees, drenched F1 goers: Singapore hit by another round of strong winds and heavy rain

khooyihang@asiaone.com

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