Widespread rain across much of Western Australia, including heavy falls in some areas, will start Friday morning and continue across the weekend.
For late May this kind of rain isn’t unusual, except in northern WA, which is currently in its dry season.
The showery and windy weekend is being caused by mid-level cloud (causing overcast conditions and steady rain) bringing tropical moisture south and possible thunderstorms. As the cloud band moves southeast it will be joined by a cold front and cut off low in waters southwest of the state, which will contribute to the rain as well and bring cooler temperatures from Sunday.
For Perth peak daytime temperatures will drop from 24°C on Friday to 19°C on Sunday and Monday. The heaviest rain in Perth is expected Saturday when 20-30mm is forecast to fall out of a total of 30-55mm between Friday and Sunday.
Areas east of Perth from Exmouth to Esperance will experience the wettest conditions, with steady rain expected.
Rain affected districts include the Western Pilbara, Gascoyne, Murchison, Central west, Goldfields, and the entire South West Land Division.
Forecasts for rain include 30-65mm across Friday and Saturday in Exmouth, 25-50mm in Esperance from Saturday to Wednesday, and 50-100mm in Albany from Friday to Wednesday.
Heavier falls are possible in isolated areas directly under thunderstorms. Gusty warm, northerly winds ahead of this system are expected through the Interior and Eucla later Friday into Saturday.