Beaches were packed as long weekend crowds flocked to the coast to cool off, amid soaring temperatures on Sunday.
The mercury had already reached the high 20s by 10am, with lifesavers and firefighters on high alert due to forecast very hot weather and extreme fire danger risk.
Top temperatures for the day were scorching at 35.7 degrees in Albion Park, 35.5 in Bellambi and 35.2 in Kiama, but they failed to break October records.
There were set in 2004, when the mercury rose to 38, 37.7 and 38.1 respectively.
There were no major rescues at Illawarra's beaches on Sunday, although a boy was taken to hospital following a medical incident at North Beach, and two teens in Austinmer were also taken to hospital following a separate medical incident.
"Was great to see so many people swimming at patrolled beaches between the red and yellow flags today [Sunday]," Surf Life Saving Illawarra duty officer Anthony Turner said.
With hot weather predicted to return on Tuesday, lifesavers are urging people to stay safe around the water.
"Know your limitations and abilities in and around the water. Watch your mates around the water," Mr Turner said.
"Always always supervise children in and around the water."
Visit the Beachsafe website for operational hours, safety tips and information on rip currents.
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