The much-anticipated storm that prompted warnings from the Bureau of Meteorology on Thursday arrived slowly - but surely - in Perth just after midday on Friday.
The sky turned dark and the heavens opened up in the city as the cold front finally rolled in, although BoM spokesman Neil Bennett said rainfall was varied right across the metropolitan area.
"Just looking at it now Perth had 6mm, but at Jandakot they've had 27mm so it really is varying," he said at 1.30pm.
"I'd say on average the southern suburbs has had about 15 to 20mm, and it hasn't been raining as long in the northern suburbs so they've had between five and 10mm."
However he said the storm was by no means over and predicted more big falls for the rest of the day.
"Because this is such a slow moving system it's going to stick around, and when it really came down in the CBD, I'd expect we'll get a couple of more downpours like that.
"This rain will probably persist until about midnight."
Meanwhile, minor flood warnings for the Preston River Catchment, to residents of the shires of Donnybrook-Balingup, Capel and the City of Bunbury, remain in place.
A Department of Fire and Emergency Services spokeswoman said just one call for assistance had been received so far, for a leaky roof in Manjimup, and that minor flooding had already occurred in the area but no homes had been impacted.
Stream rises are being seen in the Preston River Catchment system due to heavy rainfall in the last 24 hours.
Donnybrook had received 108 millimetres to 9am Friday morning, with other areas in the South West copping between 70 and 90 millimetres.
