Tens of thousands of homes may remain without power overnight after a storm swept across Perth and south-west Western Australia.
Emergency services have received more than 150 calls for help and Western Power says more than 50,000 properties have lost power, with the suburbs of Kelmscott, Gosnells and Forrestfield the worst affected.
The Weather Bureau is predicting heavy rain and wind gusts of up to 125 kilometres per hour overnight.
Western Power's Heidi Coach says crews may not be able to restore power to all homes overnight.
"It could be some time until we reconnect everybody so we are asking people very kindly if they could be patient with us," she said.
"Our crews are working in some pretty tough conditions out there, it's pretty windy and wet in places, mostly windy, to get the power back on so it could be a good evening for a candlelit dinner."
Residents in regional areas including Australind, Dandaragan and Narrogin are have also been affected by power outages.
A gust of wind tore a section of roof from the Terrace Hotel on St Georges Terrace in Perth's CBD as the storm swept over just after 11am (AWST).
One of its chimneys collapsed, sending bricks crashing to the street below and damaging a pedestrian walkway.
A number of houses and two primary schools were also damaged.
Flights departing Perth have been affected and passengers are being told to expect delays.
Hundreds of schoolies in Dunsborough were stranded after the wild weather blew away tents at the main camp ground earlier on Wednesday.
More than 40 tents were completely destroyed by strong wind gusts and many more were ripped from the ground at Dunsborough Lakes Holiday resort, where at least 600 school leavers are camping.
Owner Herbie Schaal says the weather was too severe for the tents to withstand.
"It's just ripped through them all and they're desperately trying to hold the tents together with tape and ropes but as they are hanging on to it, it's just ripping apart under them," he said.
"We are trying to help them with everything but the gale force wind and the rain is just not giving anyone a chance now."
The Department of Fire and Emergency Services says it received a number of calls about fallen trees from as far south as Australind to Marangaroo, north of Perth.
A boat has sunk off Bunbury while another was set adrift.
Police say two boats broke their moorings near Bunbury's Koombana Sailing Club this morning.
The Department of Fisheries brought one of them back to shore and anchored it safely while the search continues for the other boat.
Weather bureau spokesman Noel Pusey says farmers in the Wheatbelt have already had a lot more rain than average this month.
"There's a number of places, particularly in the Wheatbelt, that are either on or very close to their record monthly rainfall for November," he said.
Salmon Gums wheat grower Rory Graham says he is worried the rain will damage his crop.
"When wheat's had three good rain events on it, it will suffer a bit of damage," he said.
The low is expected to move off the coast overnight and early Thursday morning with temperatures returning to the mid 20s by the weekend.
© ABC 2012
17:27 EST Wallsend businesses have welcomed the introduction of a Flash Flood Early Warning system, but say it will not protect their properties from water inundation.