It's been an incredibly warm day in Sydney today, with temperatures soaring past 30 degrees before 10am.
However, a cool change is on its way, with a strong cold front moving across NSW.
According to weatherzone, there will be strong winds and the temperature will hit 13 degrees overnight.
There's also a 90 per cent chance of rain.
The area from Badgerys Creek to Liverpool may be in a storm's path.
This week will be noticeably cooler as it progresses, with termperatures in the early 20s.