Perth is set for a cold snap during Friday and Saturday the likes of which have not been felt in May since 2013.

Key points: A cold front that brought rain today will then see the temperature plunge

A cold front that brought rain today will then see the temperature plunge It has been six years since we have had two such cold days in a row in May

It has been six years since we have had two such cold days in a row in May The rain is then set to return at the start of next week

The Bureau of Meteorology (BOM) is forecasting a minimum of just 3 degrees Celsius on Friday and a maximum of 17C for both days.

"We're going to get a bit of a blast of winter, with some very cold temperatures overnight and also some low maximums as well," BOM spokesman Neil Bennett said.

"We haven't had consecutive days of 17C or below since May 2013, when we had 14.6C on the 30th and 16.2C on the 31st.

"The 3C minimum is also fairly unusual, we haven't had a May morning as cold as that since 2012 when in fact it got down to 1.3C … so it's been a long time since it's been as cool as that in May."

Balmy weather now a distant memory

After a balmy 27.6C was recorded in Perth on Wednesday, a cool and wet change swept over the city today.

The temperature reached a maximum of only 18C shortly after 10:00am and then dropped into the mid-teens for much of the afternoon.

"The reason for the cooler weather is the cold front that brought the rain up this morning [also] brought quite a significant drop in temperature … as a result of the cold air coming up behind that cold front," Mr Bennett said.

It will be beanies, scarves and gloves weather tomorrow morning on the way to work. ( ABC News: James Carmody )

A high pressure system will move in from the west behind the front, clearing up skies and bringing light winds.

"With the temperature only reaching 18C on Thursday and the air coming in from the south behind that cold front, those clear skies and light winds will mean that temperatures will drop quite rapidly on Thursday night," Mr Bennett said.

"It wouldn't be at all surprising with temperatures as low as (3C) to see frost in some areas."

Sunday is set to be a little warmer, with a minimum of 5C and a maximum of 22C.

Perth's coolest day so far this year was Good Friday, with 17.1C recorded on April 19, while the lowest overnight temperature was 5.5C recorded on May 2.

Perth weather forecast