The slight haze across the island on Tuesday is due to smoke from fires in southern Sumatra, brought over by southwesterly winds overnight, the National Environment Agency (NEA) has said.

The NEA said winds over Singapore have been "light and variable" since morning. Conditions, however, are likely to improve in the later part of the day as winds strengthen and shift in direction to blow from from the south.

Since 10am, much of the island was covered in a slight haze, with several Straits Times readers sending in photos of haze-covered scenes from their areas.

On Twitter, the hashtag #sghaze is also trending.

The three-hour PSI reading spiked to 56 as of 2pm, while the 24-hour PSI reading is 27-35, in the good range. The 24-hour PM2.5 reading is 17-22 micrograms per cubic metre.

The NEA said it will continue to monitor the situation and provide updates when there are further developments.

Send in your photos of hazy scenes in your area to stnewsdesk@sph.com.sg or tweet us at @stcom.