Why is western Sydney so much hotter than the eastern suburbs and what can be done to make summer more bearable?

Western Sydney sits in a flood plain, which traps hot air, preventing overnight cooling and increasing the heat load for the next day, experts say. Photograph: Brook Mitchell/Getty Images

A severe heatwave baking parts of eastern Australia was expected to peak on Wednesday, affecting parts of western Sydney including Campbelltown, Liverpool, Parramatta and Penrith.

Wednesday was forecast to be Penrith’s fifth consecutive day above 35C, a new record for spring since records began in 1995. The mercury there hit 48.9C in January 2020, the highest temperature ever recorded in the Sydney basin.