Much of Queensland's population lives on the coast, so those who can tolerate the sun could at least seek some reprieve in the ocean.

As long as cold water is running, people can also use tap water to cool themselves down, though it will turn into a swampy mess when none of it evaporates. Perhaps public shaded pools with a cool water source will become critical public infrastructure to help people survive heat waves if the electricity goes out.

If it's above 32 degrees and 100% humidity at all hours though, it would be pretty miserable as you wouldn't have anywhere to sleep (unless you have a car with A/C, and masses running their cars overnight will just contribute that much more to the climate change)