PERTH has been saturated with up to 10 years worth of January rain in the past 24 hours as records tumbled across the city.
The remnants of ex-Tropical Cyclone Joyce dumped more than 100mm of rain on parts of the city, with the Bureau of Meteorology predicting another 10 to 15mm of rain before conditions ease later on Tuesday.
The leafy suburb of Swanbourne has received 138.6mm since Monday, while Rottnest Island broke all January records after 143mm drenched the popular tourist spot in a little less than 24 hours.
Downed power lines have left about 400 homes without power.
Flights were delayed while hundreds of passengers circled above Perth Airport overnight, with pilots forced to abort landing attempts as winds of up to 72km/h lashed the runways.
Airservices Australia is warning passengers due to land in Perth to expect turbulence.
The State Emergency Service say they have responded to more than 329 calls for help since 9am on Monday, the majority coming from residents along the Perth coast. They include several car crashes and drivers stranded on waterlogged roads, but so far no severe damage has been reported.
Main Roads has advised motorists to check road closure updates and take extra care on the slippery roads.
A severe weather warning has been issued for residents in the Lower West, South West and Great Southern regions, stretching from the city of Bunbury to Albany, and extending from the Margaret River coast inland to Mount Barker, Katanning and Narrogin.
Widespread rainfall between 50 to 80mm is expected, with isolated falls of 120mm possible. A flood warning is in place for the Lower West.