Perth shivered to its lowest temperature for the year this morning, with the mercury sliding to 2.6C shortly before 7.30am today.

The temperature was recorded at 7.28am today and was the coldest since September 22 last year when the mercury reached just 1C.

This morning's low was the seventh time this year Perth reached a temperature noted as "cold" which is generally recorded when the temperature reaches 5C or less.

But it was not the coldest temperature in the Perth metropolitan area. The coldest spot was recorded at Jandakot overnight where the mercury reached 1C followed by Perth Airport, 2.3C and then Pearce which recorded 2.6C.

Southern Cross Airfield and Wandering reached and icy 0.2C this morning, while Collie dipped to an icy 0.8C.

Bureau of Meteorology climate information officer John Relf said it was the 55th time this year that Collie reached temperatures of 5C or less.

Mr Relf said people should expect more cold weather in the coming days as July is generally considered the coldest month of the year in WA with the average temperature for the month being 8C.

"On average, Perth has eight nights when the temperatures reach 5C or less in July," Mr Relf said.

"The greatest number of cold nights was 16 which were recorded in 1998 and 2001," he said.

While people in the Perth metro shivered overnight, those on Rottnest Island had a "balmy night", with the mercury reaching 10.8C.

Meanwhile, the Bureau of Meteorology predicts fine and sunny weather conditions for the weekend with showers developing on Monday.

PERTH LEE RONDGANGER