North Queensland health authorities says there has been a spike in the number of people being treated for heat exhaustion.
High temperatures across north Queensland are set to continue for the rest of this week, with humidity levels also climbing.
The Townsville Hospital's Dr Carl O'Cane says people should seek medical help if they have symptoms of heat exhaustion.
"The things you've got to look out for is feeling hot, in particular if you stop sweating, a sign that your body is starting to shut down," he said.
"If you have a rapid pulse, often people get a headache sometimes even dizzy, people who are working with others might notice they are becoming confused."
© ABC 2013
16:38 EST Organisers of the Mulga Bill Quick Shear at Yeoval, in Central West New South Wales on the weekend, were a bit nervous about the weather on Saturday morning; there'd been good rain on Friday night and they didn't have a 'Plan B' if things didn't clear up.