Mandurah has sweated through its warmest November night on record.
The minimum temperature dipped to a balmy 25.7C at 1.30am on Wednesday before rising to nearly 30C at 5am.
Bureau of Meteorology community information officer Patch Clapp said it was the highest November minimum temperature in Mandurah since records began in 2001.
"It's a 12-year-old record, the last one that warm in November was back in 2010 (when it reached 25C)," Mr Clapp said.
On Tuesday the temperature hit 35.5C at 3.30pm.
The warm weather was due to a trough that was sitting off the west coast.
There will be some relief for residents on Wednesday night with the mercury tipped to drop to 18C.

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