The cloud, which looks like a jewel known as the Mammatus, formed over Sydney Harbour and stretched through the city into Western Sydney this afternoon, acting as a precursor for an expected storm.
Other areas included parts of the Hunter, South Coast, southern tablelands, and snowy mountain regions. Rain is forecasted across the Sydney Basin, with a slight possibility of light hail over the far western parts of the capital.
Heading into the weekend, a bit of respite from the heat is expected on the tail end of Saturday, with cooler conditions expected.