It’s hot, sweaty, and air conditioners are working overtime – but Sydneysiders have just a few more hours of sweltering temperatures before the first southerly buster of the summer sweeps through.

Just before 2pm on Tuesday, Sydney’s CBD hit 33 degrees, while parts of the western suburbs have reached temperatures over 40 degrees.

In Penrith and Richmond, temperatures had climbed to 40 degrees by 1.59pm and 1.52pm respectively, with peaks of a sweltering 42 degrees expected. It is hotter in western Sydney than some of NSW’s regional towns, including Dubbo and Tamworth, which are expected to peak at 38 and 39 degrees.

The dew point, which is the best measure of how sweaty you’ll be, reached 21 degrees in the city and western suburbs, which the Bureau of Meteorology describes as muggy and uncomfortable.

Dr Lai Heng Foong from the Australasian College for Emergency Medicine told ABC Radio Sydney that already overcrowded emergency departments were at risk of becoming overwhelmed during extreme heat.

“I’m concerned because our hospitals are under a lot of stress, and there is already overcrowding,” she said.

NSW Ambulance acting superintendent Christie Marks said those over 60, tradies and mums with babies should especially be on the lookout for heat stress symptoms.

“Dehydration is the biggest thing that we do respond to, so drink lots of water,” Marks told Nine News.