 Both cities broke records for the most consecutive days over , while Mildura, Victoria recorded an all-time record twelve consecutive days over .The exceptional heat wave was caused by a slow-moving high-pressure system that settled over the Tasman Sea, with a combination of an intense tropical low located off the North West Australian coast and a monsoon trough over Northern Australia, which produced ideal conditions for hot tropical air to be directed down over southeastern Australia.The heat began in South Australia on 25 January but became more widespread over southeast Australia by 27 January.