Why it feels hotter than what the thermometer may be showing

Increases in temperature are more keenly felt in cities like Singapore due to the urban heat island effect. This occurs when heat is trapped by urban surfaces such as concrete and asphalt, and from waste heat generated by air-conditioning and motor vehicles, said SMU Associate Professor of Science, Technology and Society Winston Chow. This is especially felt at night, when heat stored by the built environment during the day is released, added Assoc Prof Chow. For example, in a study he recorded a temperature of 30 deg C at Orchard Road at 10pm as compared with 23 deg C in Lim Chu Kang's forest at the same time.