Temperatures are set to plummet across southwestern WA during the next few days as a cool airmass sweeps across the region.

The first cold front will move through the southwest of WA on Tuesday, causing a noticeable drop in temperature in Perth. This system will be followed by another two fronts on Wednesday and Thursday.

Collectively, these fronts will deliver a burst of cold and wet weather not seen in Perth for months. After reaching 31ºC on Monday, Perth’s temperature is only expected to reach 19-20ºC on Wednesday, Thursday and Friday, which is about 5 to 6ºC below average for mid-autumn.

Wednesday’s forecast maximum temperature of 19ºC would be the coolest day in five months, with the last 19ºC recorded on November18, 2021.

The last time Perth stayed below 21ºC for three consecutive days this early in the year was 14 years ago.

The cold fronts will also bring several days of wet and cloudy weather to southwestern WA as they move through the region. The map below shows the rainfall forecast during the next three days, with 20-40mm possible in Perth.

Image: Forecast accumulated rain between Tuesday and Thursday this week, according to the ECMWF-HRES model.

This week’s cool and wet weather after a hot and dry summer, which led to record breaking heat in Perth.

Between December and February, Perth registered 32 days at or above 35ºC and 13 days at 40ºC or higher. These were both new summer records.

Thursday and Friday evenings should also be chilly, with temperatures of 9-10ºC forecast. This is about 4 to 5ºC below average for April.

Fortunately for those that don’t like wet and cool weather, the weekend is looking mostly sunny and temperatures will rise to a pleasant 25ºC by Sunday.