SINGAPORE - You might just want to carry a brolly with you if you are heading out on Monday (Oct 23).

Thundery showers are expected over parts of Singapore on Monday afternoon, the National Environment Agency (NEA) said on Sunday in a release issued close to 6.10pm.

The agency added that there could be slightly hazy conditions on Monday morning due to the accumulation of particulate matter under light wind conditions.

NEA said that for the next 24 hours, the hourly concentration readings for PM2.5 - tiny pollutant particles associated with haze - are expected to remain in the normal band.

The 24-hour Pollutant Standards Index (PSI) is expected to be in the moderate range. The reading as of 6pm on Sunday was also in the moderate range at 66 to 73.

The likelihood of transboundary haze affecting Singapore remains low, said NEA, with showers expected over parts of Sumatra and prevailing winds forecasted to blow from the west-southwest or west-northwest over the next few days.

On Sunday, rain fell over parts of central and southern Sumatra, with 18 hotspots detected, mostly in northern Sumatra. However, there were no visible smoke plumes or haze seen.