Record rains have swamped the northern West Australian town of Broome, dumping twice the annual rainfall on the popular tourist spot in less than two months.
Tropical Cyclones Joyce and Kelvin, combined with a severe storm, have drenched the Kimberley.
Bureau of Meteorology representative Neil Bennett says Broome has broken its annual record after receiving more than 1500mm of rain.
"And it's only February," Mr Bennett told AAP.
He said the northern WA cyclone season continued until April and it was safe to assume more dangerous weather systems were likely.
"Interestingly, the season started late last year with cyclones coming in a rush at the end of March," he said.
Sections of the vital Great Northern Highway supply road remain shut, isolating people in Kimberley region towns including Broome, Derby and Halls Creek from the south of the state.
Tropical Cyclone Kelvin was downgraded to a tropical low on Monday but will continue to bring heavy rains and gale-strength winds up to 100km/h as it heads south-east across the interior on Tuesday and Wednesday.
Mr Bennett said the ex-tropical cyclone was predicted to merge with a current storm system near the South Australian border and could bring flash flooding to the town of Eucla.
He warned WA's main connection with the eastern states is by the roads and rail lines in the area.
Meanwhile, the western Pilbara and western Gascoyne regions have been very dry, suffering a severe lack of rain for more than 10 months in coastal districts.
