As at 9pm, the 24-hour reading was between 44 and 51.The National Environment Agency (NEA) said the hazy conditions experienced since late Friday afternoon could be due to hot spots to the north of Singapore. It said a total of four hot spots were detected in peninsular Malaysia while 35 hot spots were spotted in Sumatra. NEA said the hazy conditions are expected to persist overnight. On Thursday, NEA said that an expected change in the monsoons in the later part of this month may pose some risk of transboundary haze. The agency said in a statement that with the expected transition from the Northeast Monsoon to the inter-monsoon period, winds in the region will turn light and variable in direction, and will pose “some risk” of transboundary haze should hot spots in Sumatra persist and the prevailing winds in our region temporarily turn westerly.