Sydney’s maximum temperature peaked at 42.2°C this Saturday, January 10, making it the second time in the summer of 2025/26 that the harbour city has reached exactly that mark (the other day was December 19).

The Saturday scorcher made it the first time since 2013 that two days in the same Sydney summer have exceeded 42°C at the city's official weather station at Observatory Hill, near the southern pylon of the Sydney Harbour Bridge.

Many Sydneysiders still remember that 2013 summer, as the mercury at Observatory Hill peaked at 45.8°C on January 13, which remains the site’s hottest day on record.

For those who love their heat stats, the hottest temperature ever recorded in any Sydney suburb (and indeed in any suburb of any Australian capital city) was a remarkable 48.9°C at Penrith, in far western Sydney at the foot of the Blue Mountains, on January 4, 2020.

Image: The heat spread across from far northwestern NSW, where Saturday's highest temperatures were only a degree or so above most Sydney weather stations.

Sizzling across the Sydney basin

Temperatures were hot over the entire Sydney basin, as northwesterly winds pushed hot air from the continent’s interior right across the city, negating the sea breeze which often moderates temperatures near the coast.

Some of the noteworthy temperatures to 5pm Saturday included:

• Holsworthy (Defence) in southwest Sydney registered the city’s highest temperature, with 43.5°C.
• Badgerys Creek (site of the new international airport) reached 42.8, while Sydney Airport, 45km east and on the shores of Botany Bay, reached almost the same temperature, with 42.7°C.
• Penrith endured its third straight day of 42°C or higher, with a maximum to 5pm of 42.5°C after a high of 42.5°C on Friday and 42.1°C on Thursday.

Southerly to cool things down, several days of showers to follow

Just as Melbourne copped extreme heat on Friday before cooler air arrived in the evening, Sydney can expect one of its trademark southerlies on Saturday evening.

While easterly sea breezes cooled some coastal suburbs down from about 4:30pm onwards – with the city cooling by almost 10 degrees in an hour – the airmass from the south won’t make its way northwards to cool the whole city down until around 9pm.

By Sunday evening, showers should arrive and they should stick around well into the working week.

Maximum temperatures in Sydney most days will be much closer to the January average of 26°C.