Sydney had its wettest July on record this year after only two weeks, passing the 1950 record of 336.1mm on the way to a total of 404mm. March broke a 1942 record of 521.4mm when 554mm fell.
Some of the state's rural inland towns were already flooded, with television footage showing damaged roads and residents moving farm animals to higher ground.
Hundreds of homes have been inundated in and around Australia’s largest city in a flood emergency that was causing trouble for 50,000 people, officials said
Days of torrential rain have caused dams to overflow and waterways to break their banks, bringing a fourth flood emergency in 16 months to parts of the city of 5 million people. Evacuation orders and warnings to prepare to abandon homes were given to 50,000 people, up from 32,000 on Monday, New South Wales Premier Dominic Perrottet said.