The 2023 NRL Grand Final will be contested tonight between the Penrith Panthers and the Brisbane Broncos at Sydney’s Accor Stadium, and no matter what happens on the field, this will very likely be, quite literally, the hottest Grand Final in the NRL era, as temperatures soar into the mid 30s. 

Amazingly – considering it is traditionally played in early October – this will be the 5th NRL Grand Final where the maximum temperature has surpassed 30°C, including 3 straight years from 2013-15. Of the previous four occasions, the highest temperature was in 2014, where the maximum temperature reached 34.7°C. 

Image: forecast maximum temperatures for Sun 1st October 

So why is Sydney so hot today? The reason is an extensive trough sprawling from northwest WA, transporting heat towards NSW. You can almost see exactly where the trough is in the above image if you follow the purple and red tongue from the Pilbara through the interior and into NSW. In addition, hot north-westerly winds are pouring through the Sydney basin today, helping to drive up the temperatures. 

In total, 3 games are being played including the State Championship kicking off at 1:20pm, and the NRLW Grand Final playing at 3:55pm, before the NRL Grand Final kicks off at 7:30pm.  The forecast temperatures for the first two games are smack bang in the mid-30s, and even at 7:30pm, the temperature is still likely to be around 30°C, which is still extremely warm for a night kick-off. 

Image: hourly forecast for Sydney Olympic Park for NRL Grand Final day 2023 

As the game wears on, a southerly buster moving up the coast will cause temperatures to cool quickly, falling to about 22°C around the time when either the Panthers are celebrating their 3rd straight premiership, or the Broncos lifting the trophy for the first time in 17 years. 

Image: forecast wind gusts at 10pm AEDT Sun Oct 1st

For those heading to the game, make sure you stay cool and drink plenty of water, especially if you’re making it a big day out. With the southerly buster on the way, also best to prepare for a cool change on your way home.