Residents in multiple states should prepare to swelter over the weekend as two football finals take place in unseasonably hot spring weather.
Temperatures are expected to hit 29C in Melbourne on Saturday, setting the day up to be among the four hottest AFL grand finals - although short of the 31.3C record set in 2015.
Adelaide is also set for a high well above the September average, with a forecast peak of 32C, while temperatures in the mid-high 20s are expected in Sydney, Brisbane and Canberra.
The mercury is due to soar higher again in the NSW capital on Sunday when records could tumble for the hottest NRL grand final in recent history.
The hot weather also coincides with a long weekend in NSW, South Australia and the ACT, when people are expected to hit the roads and beaches.
Rugby league officials will put hot-weather provisions in place for the clash between the Brisbane Broncos and Penrith Panthers at Sydney Olympic Park, in the city's west.
The daytime temperature at the site is forecast to reach 36C, which would be the hottest grand final day since observations began at the location.
A peak temperature of nearly 30C is also expected for Canberra, although the mercury is forecast to drop to the low 20s for much of Australia's south and west.
The grand final half-time break could be extended by 20 minutes, with a minute-long "time out" if needed at the mid-point in each half.
However, the Bureau of Meteorology's Angus Hines said the temperature was expected to drop to the high 20s in time for the evening kick-off and fall further during the match.
Trainers will carry water throughout the game in a relaxation of the rules, while fans and iced towels will be available on the sidelines for players.
An extreme fire danger rating is expected to be in place on Sunday for Greater Sydney, the Hunter and the far south coast regions.
