The Bureau of Meteorology has issued a severe heatwave warning for a vast swathe of the state stretching from Coolangatta north to Townsville and across to the Northern Territory border.
The only areas outside the warning zone are southwest Queensland and Cape York.
The bureau says maximum temperatures will be in the low to mid-40s and overnight temperatures won't drop below the mid-20s in central and western Queensland from Tuesday.
On the east coast, temperatures will rise into the mid to high 30s during the day and won't dip below the low 20s overnight.
"Temperatures will continue to rise later in the week, with heatwave conditions intensifying and extending in area," the bureau said.
"Locations likely to be impacted include Brisbane Metropolitan Area, Croydon, Caboolture, Doomadgee, Esk, Hughenden and Mount Isa."
The warning urged people to find a place to keep cool such as a home, library, community or shopping centre, close the blinds or curtains early to keep the heat out and use fans or air conditioners if possible.
Premier Annastacia Palaszczuk urged people to keep hydrated, stay sun safe and ensure their pets were comfortable as well.
"Stay safe, Queensland - it's set to be a hot few days," she Tweeted on Tuesday.
Heatwave conditions are potentially dangerous for older, unwell, pregnant, breastfeeding and younger people, and babies, the bureau said.
Queensland Ambulance Service clinical director Tony Hucker said heat stress symptoms included feeling tired or having a headache, but often other people noticed such symptoms first.
"So if you look at someone and (think) 'gee they look really pink, they look flushed and don't look really well', or starting to exhibit some abnormal behaviour, you need to grab them and get them into a dark shaded spot or inside, (and) get them drinking," he said in a recorded statement.
"If they cannot drink ... that's a sign to call Triple 0, that's a dangerous sign. If people are vomiting and can't keep fluid down they need medical help."
17°C