The mercury cracked 33 degrees at midnight in Albion Park and 31.5 at 3am in Bellambi as sheets clung to backs across the region overnight.  

"It would definitely be up there with the hottest nights on record," Weatherzone meteorologist Graeme Brittain said on Saturday morning, describing the peak as "quite exceptional."

Today is expected to be cloudy with a medium chance of showers this morning and again this evening, according to Weatherzone.

There’s a chance of a thunderstorm in the north in the morning and early afternoon and daytime maximum temperatures of 30 to 36.

"It will be cooler tonight, but it will still be humid and uncomfortable," said senior Weatherzone meteorologist Jacob Cronje.

The heat has been delivered by a low pressure trough moving from the north-west of the state.