The CBD will see maximum temperatures of 30 degrees for Friday, while 35 degrees is expected inland at Sydney Olympic Park.
Hornsby will reach 36 degrees, while Parramatta is predicted to reach 37 degrees. Campbelltown will see maximum temperatures of 39 degrees, with 40 degrees expected at Liverpool.
The statewide heatwave has already broken records across regional NSW in Narrandera and Hay Airport, while Albury saw its hottest December day in 26 years on Thursday.
According to the bureau, the heatwave is likely to stick around a while.
“There will be a bit of relief for Sydney during the first few days of the year due to a small trough developing in the south-east corner of the state,” Neynens said. “It will cool things down a little while, but at this stage it doesn’t look like a strong change.”
Sydney will also feel a slight sea breeze this afternoon, with winds of up to 40km/h expected to push a cool change in from the coast.
The breeze won’t bring much relief throughout the night though, with temperatures predicted to sit in the low 20s overnight.
The heatwave is expected to peak over the weekend, with tops of 31 degrees on Saturday and 34 degrees on Sunday for the city.
Western Sydney will continue to sizzle through scorching temperatures, with 42 degrees predicted on Saturday and 41 degrees on Sunday.
Sydney’s air quality has been upgraded to “fair” after two days of “poor” air levels due to ozone pollution, with fire danger remaining high.
Sarah is a journalist for The Sydney Morning Herald.